Poster Session 2
12:45 PM to 2:15 PM
- Presenters
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- Joshua Matthew (Josh) Abel, Junior, Aquatic & Fishery Sciences
- Siri Francis Collins, Senior, Biology (General)
- Joseph James (Joe) Dupris, Senior, American Indian Studies
- Kenneth John Kucey, Senior, Political Science, Aquatic & Fishery Sciences
- Katie (Kate) Olson, Senior, Aquatic & Fishery Sciences Mary Gates Scholar
- Sara Yihua (Sara) Wang, Senior, Environmental Science & Resource Management (Wildlife Conservation), Biology (General)
- Hannah Katherine (Hannah) Wise-Maas, Senior, Environmental Science & Resource Management
- Tyler Terry Wollam, Senior, Environmental Science & Resource Management
- Mentor
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- Christian Grue, Aquatic & Fishery Sciences
- Session
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- MGH 241
- Easel #147
- 12:45 PM to 2:15 PM
Imidacloprid (IMI) may be a viable alternative to carbaryl for controlling burrowing shrimp (Neotropea californiensis) that destabilize sediments resulting in poor survival and low yields of the commercially harvested Pacific oyster (Crassostrea gigas). Previous laboratory tests indicate the shrimp are overtly affected (immobile, cannot burrow) when exposed to IMI concentrations in sediment pore water, but are not killed. These results contrast sharply with observed efficacy in the field, i.e. mortality 72-96 hours post application and subsequent reductions in burrow counts. Understanding the factors governing efficacy in the field may improve control. We exposed 10 adult female shrimp that had burrowed within native sandy sediment to IMI (Nuprid® 2F) for 96 hours simulating the theoretical maximum pore water concentration (146 ppb) associated with an application of 0.5 lbs active ingredient [ai] per acre. We compared the response of the shrimp to that of an equal number of negative controls, and five shrimp in a comparable pore water-only exposure, and five in clean seawater. Behavior was monitored daily and water quality was measured at the end of the test. As expected, all shrimp in the water-only IMI exposures were overtly affected, but survived. Eighty percent of the shrimp exposed to IMI within their burrows died, whereas 90 percent of the negative controls survived. Dissolved oxygen (% saturation) varied among treatments (clean seawater: 51-69.6%; seawater + IMI: 42.4-57.4%; clean sediment surface water [alive]: 4.1-20.1%, [dead]: 3.4%; sediment + IMI surface water [alive]: 5.4, 57.9%, [dead]: 4.2-65.4%). Results suggest the shrimp can tolerate very low dissolved oxygen within sediment without IMI, but their sensitivity to IMI increases due to factors associated with their impaired ability to move water within the sediment.
- Presenter
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- Raymond Alvarez, Freshman, Pre-Sciences
- Mentors
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- Chantel Prat, Psychology
- Andrea Stocco, Psychology
- Session
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- Commons West
- Easel #13
- 12:45 PM to 2:15 PM
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by broad social and cognitive impairments and the presence of stereotyped, repetitive behaviors. Our research examined the hypothesis that impairments in neural signal routing in ASD underpin behavioral symptoms. Specifically, we investigated structural and functional differences in the basal ganglia (BG), a group of subcortical nuclei that regulate signals to frontal cortex. The BG is known to regulate movements, balance, and posture and their abnormal development has been related to motor impairments in ASD. It is necessary to extend these investigations, as previous research did not account for the relation between BG structure and function, or the role of the BG in complex cognitive tasks. In the current experiment, anatomical tracings of two of the key input stations of the BG (the caudate and putamen) were generated for 31 individuals, including 14 with ASD and 17 controls. To determine whether the size of the BG nuclei correlated with their functional influence over cortical regions, we correlated our volumetric measures with indices of effective connectivity, measured using dynamic causal modeling analyses of an fMRI data set. Our results indicated that across all individuals, there were reliable negative correlations between the size of the BG and its modulation of synchronization between several cortical regions. This finding was particularly evident in the individuals with ASD. However, inconsistent with previous investigations, between groups t-tests showed that there were no significant differences in absolute BG volume between groups. Future analyses will account for total brain volume to see whether absolute value or relative value of the BG account for differences in network-level signal routing properties in individuals with ASD. We will also correlate these findings with behavioral measures to establish its relevance for the symptoms of ASD.
- Presenter
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- Preslav Petrov (Preslav) Angelov, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Raj Bordia, Materials Science & Engineering
- Session
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- MGH 241
- Easel #131
- 12:45 PM to 2:15 PM
Aerospace vehicles, such as reusable spacecraft and hypersonic flight vehicles, require materials that can both provide high thermal resistance and high mechanical strength. Thermal insulation is required to protect the vehicle interior including occupants from the high heat of reentry and mechanical strength is required to withstand the variety of loads including the forces experienced during launch. In general, it is difficult to meet both these requirements at a high level since the normal way to increase thermal resistance of porous ceramics is to increase the porosity but this reduces strength. We are currently developing and investigating anisotropic porous ceramics that have the potential to optimally meet both these requirements. We are making the anisotropic porous ceramics from through a route called polymer derived ceramics (PDCs). The class of PDC’s that is being investigated is siloxanes, which decompose at high temperatures (~800oC) into a SiOC ceramic. These materials have excellent high temperature resistance including creep and low thermal conductivity. Polymethylphenylsilsesquioxane (Waker H44) is first cross-linked and milled into a fine powder. The powder is then pyrolyzed to a SiOC ceramic that is then milled into a fine ceramic powder. A water-based slurry is made and poured into a mold that sits on a cold copper rod that is cooled in a liquid nitrogen bath. This causes ice crystals to form in the slurry which grow perpendicular to the copper rod. The frozen component is then freeze dried, causing the ice to sublime leaving a highly anisotropic porous structure. The thermal and mechanical properties will be measured in the longitudinal and transverse directions and the properties of these anisotropic porous microstructures will be compared to those of isotropic porous ceramics of similar porosity.
- Presenter
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- Jixia Ao, Senior, Anthropology, Comparative History of Ideas
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #2
- 12:45 PM to 2:15 PM
In the past few years, there have been some prominent sexual assault scandals in American sports, such as the Pennsylvania State University football and Duke University lacrosse scandals, as well as a variety of lesser known cases. I am interested in how the mainstream and alternative media depict sexual assault in sports, and what values and social norms are revealed by these depictions. Do media portrayals of sexual assault in sports change depending on the race, gender, and age of the victim and perpetrator? I predict that these portrayals will follow common racial and gender discourses in America by vilifying black men accused of sexual assault more than white men, and minimizing or normalizing the rape of adult women. The rape of children, especially young boys, is more shocking and therefore elicits a stronger media response. I will investigate this question through discourse analysis of news articles, news websites, and blogs, and through analyzing the images that accompany the articles and blogs. My research will be linked to the feminist concept of rape culture. It will also build upon work such as the article Innocent Until Proven Innocent, a discourse analysis of the Duke lacrosse rape scandal written by David J. Leonard. In his analysis, he concludes that after the accusation of upper class white male athletes by a black woman, the mainstream media framed the case as showing unfair prejudice against white men and unfair credibility given to the black woman’s story just because of her race. By analyzing portrayals of sexual assault in sports, I hope to shed light upon cultural assumptions, values, and stereotypes that surround sexual assault in sports, and in the United States in general.
- Presenter
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- Ekaterina Dmitrievna (Ekaterina) Balakireva, Junior, Anthropology: Anth of Globalization, Near Eastern Studies (Culture & Civilization)
- Mentor
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- Holly Barker, Anthropology
- Session
-
- Commons West
- Easel #3
- 12:45 PM to 2:15 PM
In this paper I will do a cross-cultural comparison of attitudes towards chess in the United States and Uzbekistan to answer the question: “is chess a sport or a game and how does this vary in the U.S. and Uzbekistan?” Chess is considered as an official sport in Uzbekistan, where chess players are considered athletes. Therefore they go through physical evaluation and drug tests before participating in upper level tournaments. Meanwhile the U.S.’s view on chess commonly assigns it a status of a game, not a sport. This attitude comes from a popular belief that sport can only be a challenging physical activity, nothing less. This evidence shows that popular culture dictates the way we view sports and activities. The media impacts what categories we assign them, the amount of coverage of the topic, or in case of chess, lack thereof, and stereotypes about chess and people who play chess competitively. Through my positionality, analysis of media coverage, participant observation, and interviews I will examine the differences in cultural attitudes towards chess in both countries. The outcome of the research will shed some light on the understanding of cultural differences and values put on human activities in the time of massive globalization. As a result the data produced and analyzed through the research will be helpful in creating new types of activities related to chess and intellectual engagement for school kids that will in turn transform certain views on sports.
- Presenter
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- Nathan (Nate) Belmore, Sophomore, Physics, Mathematics, Seattle Central College
- Mentor
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- Blayne Heckel, Physics
- Session
-
- Balcony
- Easel #99
- 12:45 PM to 2:15 PM
With any particle physics experiment, precision is paramount. In experiments with electromagnetic shields, the inherent magnetic field noise from the shield itself can impede the accuracy of high precision experiments. For this research project I designed a model of an electromagnetic shield to find the magnetic field noise of the shield; the results of which can be used to increase the precision of a particle physics experiment being conducted at the University of Washington, searching for a potential source of time reversal symmetry by looking for a permanent electric dipole moment of a specific isotope of mercury (the existence of which would suggest a source of CP-violation). The cylindrical electromagnetic shield was modeled in the finite element analysis application, COMSOL Mulitphysics. The model is initially configured with a single magnetic dipole arranged on the axis of symmetry of the magnetic shield. The accuracy of the model is then compared to an analytic solution found by S.-K. Lee and M. V. Romalis at Princeton University. After refining the model to reflect the analytic solution, the number and orientation of magnetic dipoles is changed, producing the first, second and third derivatives of the magnetic field noise of the shield being used. Accounting for the magnetic field noise will increase the sensitivity of the experiment being conducted.
- Presenter
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- Olivia B. (Olivia) Bement, Senior, Earth and Space Sciences: Geology
- Mentor
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- Elizabeth Nesbitt, Earth & Space Sciences
- Session
-
- Balcony
- Easel #106
- 12:45 PM to 2:15 PM
The goal of this study was to obtain an age of the marine Quillayute Formation by correlating fossils from other similar rocks in Washington and Oregon. The Quillayute Formation, located along the outer coast of the Olympic Peninsula, Washington, consists of fossiliferous marine sandstones and siltstones, and its age has been controversial. Obtaining the correct date will allow for further understanding of the geologic history of the Olympic Peninsula, especially the rates of tectonic uplift and determining the climate at time of deposition. The Quillayute Formation has 37 identified species of fossil gastropods and bivalves. These fauna have been compared with those of the geographically and temporally closest units, the Quinault Formation (Washington) and the Empire Formations (Oregon). The Quinault Formation is Early Pliocene in age (3.6-5.3 million years), based on benthic foraminiferal biostratigraphy. The age of Empire Formation is Late Miocene (5.3-11 million years), determined by magnetostratigraphy and diatom biostratigraphy. To obtain the age of the Quillayute rocks, a comparison of age ranges of each of the correlative species was made. Results of this identified 15 species from the Quillayute Formation that also occur in the Empire Formation, and are apparently restricted to the Miocene. Six species are in common with the fauna of the Quinault Formations and those are still-living taxa.
- Presenters
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- Amy Renee (Amy) Bestick, Senior, Biology (Physiology)
- Chris W (Chris) Lewis, Senior, Biochemistry
- Mentor
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- Paul Nghiem, Dermatology
- Session
-
- Commons West
- Easel #24
- 12:45 PM to 2:15 PM
Merkel Cell Carcinoma (MCC) is a rare, aggressive, neuroendocrine cancer of the skin. The disease is associated with a virus and is strongly linked to immune system function. Disease-specific mortality is >40% and few effective treatments are available for advanced disease. MCC metastases are typically treated by chemotherapy and/or radiation therapy (RT) delivered over >20 sessions. These options are usually successful at shrinking the targeted lesions, but these effects are often short-lived and/or associated with significant side effects. Mouse model data suggest that RT delivered in a single dose is more effective in promoting tumor immunity and that subsequent RT fractions suppress the function of lymphocytes that are recruited to the tumor. Therefore, we explored the use of single dose RT for MCC metastases. 28 patients with a total of 78 tumors were treated with a single dose of RT between 2010-2013. 86% of treated tumors showed a response that persisted for over 6 months. Overall, 45% of treated tumors had a complete radiological/clinical response and an additional 41% had partial responses (>50% reduction in size). These results are encouraging and show that single-dose RT is an effective palliative strategy with minimal side effects.
- Presenter
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- Michael Joseph (Mike) Bocek, Senior, Biochemistry Amgen Scholar, Goldwater Scholar, Mary Gates Scholar
- Mentors
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- Suzie Pun, Bioengineering
- David Chu, Bioengineering
- Session
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- Commons East
- Easel #78
- 12:45 PM to 2:15 PM
A major obstacle in the efficient delivery of genes using non-viral vectors is sequestration and subsequent degradation of the vector in the endosomal/lysosomal trafficking pathway. While incorporation of membrane-lytic peptides into gene delivery vectors has been shown to increase transgene expression by disrupting the endosomal vesicles, non-specific membrane-disruption caused by these modified vectors leads to significantly increased toxicity. One approach to mitigating this increased toxicity is to mask the membrane-lytic peptides inside a pH-responsive micellar core that destabilizes during vesicle acidification in the endosomal/lysosomal pathway, revealing the membrane-lytic segments only when internalized. Incorporating pH-responsive imidazole elements in the hydrophobic micelle core which become charged under acidifying conditions can disrupt the micellar structure by electrostatic repulsion, leading to display of the active peptide, membrane lysis, and increased DNA delivery to the cytoplasm. After synthesis of the pH-responsive motif a panel of representative DNA delivery polymers will be evaluated for pH-responsiveness, transfection efficiency, and cytotoxicity.
- Presenter
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- David Alexander (David) Boe, Senior, Neuroscience
- Mentor
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- Chet Moritz, Neurobiology & Behavior, Physiology & Biophysics, Rehabilitation Medicine
- Session
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- Commons East
- Easel #60
- 12:45 PM to 2:15 PM
Cervical spinal injury can result in a loss of function in the hands and arms. Restoration of hand and arm function is nearly 5-fold more important to patients than restoration of other functions. A major difficulty in restoring function lies in overcoming the formation of perineuronal nets (PNNs) and the accumulation of chondroitin sulfate proteoglycans (CSPGs), which contribute to the scar around the lesion site. The disruption of CSPGs in both the scar and PNNs is possible with Chondroitinase ABC (ChABC), and more chronically, through the use of a novel intracellular sigma peptide (ISP). The inhibition of CSPGs allows for axonal regeneration, which may be guided through the use of intraspinal microstimulation (ISMS). Preliminary results shows that the combination of these approaches act synergistically, leading to much greater recovery than through ChABC and ISMS alone. Functional recovery is assessed through a series of behavioral tests, including a trained forelimb reaching task and the Irvine, Beatties & Bresnahan test (IBB). These behavioral tasks are designed to measure attributes that are important for upper limb rehabiliation, such as spasticity, ability to grasp, movement in the wrist and digits, and plantar contact. If successful, this treatment may be used to rewire spinal circuits around a lesion and restore function below the site of the lesion.
- Presenter
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- Richard James (Richard) Boice, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr Mary Gates Scholar, NASA Space Grant Scholar
- Mentor
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- Fumio Ohuchi, Materials Science & Engineering
- Session
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- MGH 241
- Easel #140
- 12:45 PM to 2:15 PM
This investigation focused on the unique electrical behavior of exfoliated graphene; planar sheets of carbon atoms stripped from bulk graphite flakes. Specifically, the doping effect from self-assembled monolayers (SAMs) on the graphene surface was examined. Previous research has found that certain peptide SAMs are capable of influencing the electrical nature of graphene as both n-type and p-type dopants. This phenomenon can likely aid in development of biosensing and “lab on a chip” technologies. Graphene prepared by the scotch tape method was exposed to chemical solutions of tyrosine (Y) and phenylalanine (F) amino acids. These results are compared with the behavior of similarly deposited GrBP5, a peptide sequence selected for its high binding affinity to graphite. To measure the conductivity and current-voltage profile of graphene doped with each material, graphene field effect transistors (g-FETs) were fabricated on a silicon oxide substrate. Previous research has confirmed GrBP5 is a p-type dopant (electron acceptor). Data collected in this investigation suggests that the tyrosine binding group of GrBP5 is likely the electron acceptor, based on its highly similar doping effect. This p-type nature may be due to the aromatic functional group of tyrosine and would be recommended for future investigation. Furthermore, phenylalanine was found to be an n-type dopant, exhibiting a lower magnitude of doping despite its chemical similarity to tyrosine. By understanding the role of specific amino acids in peptide SAMs for g-FET applications, a large range of peptides may be integrated into this technology, leading eventually to novel biosensing devices.
- Presenter
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- Garrett Lincoln (Garrett) Bowen, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Peter Pauzauskie, Materials Science & Engineering, U. Washington
- Zach Rousslang, Chemistry
- Session
-
- MGH 241
- Easel #141
- 12:45 PM to 2:15 PM
Palladium is a part of the Platinum Group Metals (PGM), and is highly used as a catalyst in many applications such as in an automobile’s catalytic converter. It has also been successfully used for hydrogen gas sensing devices. Employing low-cost, efficient means to synthesize palladium nanowhiskers in the lab has been the focus of my research thus far. Hydrothermal synthesis and dislocation mechanisms have been used for the growth of palladium nanowhiskers using a palladium (II) chloride charge. The hydrothermal synthesis involved chemical reactions as well as thermal reactions in the growth of the nanowhiskers. In the dislocation mechanism, the growth of the whiskers is the result of the thermal decomposition of palladium chloride to palladium plus chlorine gas. Scanning electron micrographs from the first four runs of the hydrothermal synthesis showed little to no nanowhiskers. The first run of the dislocation mechanism grown samples is currently awaiting characterization. Future work for my research involves many more dislocation mechanism growths of the palladium nanowhiskers, as well as an attempt to use electrochemical deposition as a third technique in producing these whiskers. The application of these nanowhiskers in hydrogen gas sensing is based on the change in the conductance of the whiskers upon absorption of hydrogen. This allows for highly sensitive sensors to be made.
- Presenter
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- Taylor Lee (Tay) Boyd, Freshman, Pre-Sciences
- Mentor
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- Wendy Raskind, Medicine, Psychiatry & Behavioral Sciences
- Session
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- Commons East
- Easel #74
- 12:45 PM to 2:15 PM
Dystonia Chorea is a very rare disease that includes the recurrent, aimless, uncontrollable, and sometimes painful movements of chorea, as well as the characteristics of dystonia, such as twisting, contorted movements or abnormal postures caused by sustained muscle contractions. The objective of the Raskind Lab is to identify the genes that are responsible for rare forms of neurogenetic diseases using exome sequencing and linkage analysis. For the Dystonia Chorea family, chromosome X was selected for initial analysis because the pedigree suggested possible X linkage. Chromosome 4 and 9 held candidate genes with some evidence for linkage. Within these regions, the variants were filtered for sequence-read quality and sharing of variants by affected people. Only variants for which the affected people were heterozygous for the alternate and reference bases were further considered. We did literature searches for protein functions and disease similarities with Dystonia Chorea, however none were identified. We will assess a more complete linkage analysis to identify new regions of interest on other chromosomes for analysis of exome variants.
- Presenter
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- Kevin Braun, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Brian Flinn, Materials Science & Engineering
- Session
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- MGH 241
- Easel #132
- 12:45 PM to 2:15 PM
The aerospace industry today utilizes composite materials for a number of structural components due to their high strength to weight properties. Assembling these composite parts to an airplane currently requires fasteners such as bolts or rivets, even though they add weight and reduce the mechanical properties of the composite parts. Integrated monolithic composite structures not requiring bonding or fastening could improve the strength, fuel efficiency, and ease of assembly of a commercial airplane. Cellular Core Technology (CCT) has been used to create double-box beam composite structures that do not require traditional fastening. The cellular cores provide an internal surface which can apply heat and pressure to all surfaces of a part allowing for high consolidation of complex structures. The consolidation at joints within integrated structures has been a prospective problem, leading to high void content and stress concentrations causing premature failure. The effect of fiber orientation on the expansion of the cellular cores was studied to determine if the fibers restrict the pressure provided by expansion. Double box beams were fabricated while altering the fiber orientation of the carbon fiber plies between 0/90 degrees and +/-45 degrees. After curing, the expansion of the cellular cores for each structure was investigated in order to determine the effect of fiber direction on the restriction of cellular cores and subsequent porosity in the joints. Optical microscopy was used to assess porosity around the joints of each double box beam. Mechanical tests were performed using Digital Image Correlation (DIC) to evaluate the effect of fiber orientation on the stress and strain fields throughout the T-joint geometry. Future work will include determining additional factors that affect the porosity of the joints such as the relationship between the number of plies and the expansion capabilities and the expansion limits for the cellular cores.
- Presenter
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- Chelsea Ray (Chelsea) Brossard, Senior, Neuroscience, Biochemistry NASA Space Grant Scholar
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
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- Commons East
- Easel #62
- 12:45 PM to 2:15 PM
We are using an animal model to explore the possibility that fetal ultrasound exposure in utero can be a contributing factor of autism. The Williams and Casanova Triple Hit Hypothesis suggests that autism is caused by a combination of genetic predisposition, a specific period of developmental vulnerability, and exposure to environmental factors during that time of vulnerability. We hypothesize that ultrasound is an environmental factor contributing to autism in those who are genetically predisposed. A previous study found that prenatal ultrasound exposure affects neuronal migration, indicating that ultrasound is not completely harmless to the developing brain. Our experiment will use an animal model of three strains of mice with varying degrees of predisposition to autistic-like behavior. Some pregnant mice will be anesthetized and exposed to a clinically relevant dose of ultrasound while control mice will be subjected to the same procedure with the ultrasound turned off. When the mice pups are 3 and 6 weeks of age, we will use a variety of behavioral tests to assay for autistic-like characteristics. Examples of autistic-like behaviors include reduced play, anxiety in open areas, little curiosity for a novel mouse, and affinity for darkness. Results of our study may relate ultrasound exposure to autism, which would lead to further animal studies and, eventually, recommendations on the use of ultrasound on pregnant women. A positive correlation between ultrasound and autism would suggest that pregnant women should be exposed to ultrasound only long enough to assay the fetus' health.
- Presenter
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- Yoni Ivens (Yoni) Browning, Senior, Applied & Computational Mathematical Sciences (Biological & Life Sciences)
- Mentors
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- Eric Shea-Brown, Applied Mathematics
- Natasha Cayco Gajic, Applied & Computational Math Sciences
- Session
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- Commons East
- Easel #72
- 12:45 PM to 2:15 PM
Synapses, the connections between neurons, are not constant in strength but instead are plastic, adjusting due to various biophysical rules. While various types of plasticity have been identified, the interaction of different plasticity rules in a network of neurons in not well understood. We consider the behavior of two experimentally observed forms of synaptic plasticity, homeostatic and spike time dependent plasticity (STDP), and seek to exploit these rules to tune a model neural network towards a state in which activity throughout the network maintains dependence on its inputs. Our network consists of firing neurons arranged in layers connected in a sparse, feed-forward manner. Reliable propagation of layer-wide firing rates without all neurons firing together (synchrony) is required to achieve graded transmission of input rates, that is, signal transmission. Plasticity is introduced to our network through mathematical learning rules. One of our learning rules, STDP strengthens causal linkages by increasing or decreasing synaptic weights depending on the timing of pre- and postsynaptic activity. STDP by itself is often unstable, causing synaptic weights to grow without bound. We therefore attempt to stabilize STDP with a homeostatic rule, adjusting the weights of all of a neuron’s incoming synapses in order to achieve some intrinsic firing rate. While current literature has focused primarily on the behavior of these rules in single neurons or in rate-based systems, we examine the interactions between these rules in a spiking, stochastic system with dynamic inputs, and their effectiveness in tuning such a network towards reliable rate propagation. Our hope is to shed light on the development of cortical networks able to perform successful computation.
- Presenter
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- Jesse Lorenzo Butterfield, Senior, Mechanical Engr: Nanoscience & Molecular
- Mentor
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- Nathan Sniadecki, Mechanical Engineering
- Session
-
- Balcony
- Easel #87
- 12:45 PM to 2:15 PM
When cells migrate, they undergo a complex process of signaling pathways coordination and interaction with their surrounding environment. Actin filaments polymerize at the leading edge of the cell membrane, pushing it forward and allowing for the cell to bind to new sites in the extracellular matrix. In order to sophisticatedly study the process of cell migration, one must pay close attention to the initial binding points, or nascent adhesions, that can either fall apart early and cause the front of the cell to collapse, or grow into the larger focal adhesions that provide the mechanical support for the cell in the extracellular matrix. Though tools have been created to study the mechanics of cell forces, there is a distinct lack of ability to measure the extremely small forces created by cells, such as the contraction of a single filopodia. This work serves to develop such a tool, in the form of polydimethylsiloxane (PDMS) nanopost arrays, via soft lithography manufacturing techniques. These nanoposts can be treated as tiny cantilever beams by which deflection can be immediately translated to force, using known dimensional and material properties of the posts. Fabrication of the posts consists of a single-cast of PDMS onto silicon negative molds and curing the posts at 110° C at low vacuum pressure. It has been determined that vacuum pressure is necessary to achieve the maximum post aspect ratio, due to surface tension issues between the liquid PDMS and the silicon chip. The gas permeability of PDMS allows for the air contained in the holes of the master chip to escape and be replaced by liquid PDMS while curing. The success rate of nanopost fabrication is characterized by relating post aspect ratios to vacuum pressure of the curing environment, which are found to correlate.
- Presenter
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- Rowan Carrick, Junior, Religion, University of Puget Sound
- Mentor
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- Jonathan Stockdale, Comparative Religion, University of Puget Sound
- Session
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- Commons West
- Easel #35
- 12:45 PM to 2:15 PM
Contemporary US society has in many ways written off self-mutilation, the deliberate damage or modification of one’s body tissue without intention of suicide, as a pathological act whose roots lie in mental illness and destruction beyond any sort of rationality. Often, self-mutilation is linked to suicidal behavior, but even when it isn’t it bears a transgressive nature and is frequently met with repulsion. In order to understand and examine the effects of the transgression of self-mutilation on individuals and larger communities, I took into account some ways in which individuals in specifically religious contexts have been marginalized by these practices. Parts of the Lakota Sun dance involving self-mutilation were banned in the US between the years 1895-1978 and the Modern Primitives, a group that emerged in the late 1960s and 70s seeking to reclaim self-mutilating religious rituals were met with extreme ostracism. In my research I explored spiritual self-mutilation as a vehicle for connection to something beyond an individual’s bodily limits, examined the physical and psychological capacities humans have to endure intense physical sensation, and looked at the implications of the process of physical healing as a powerful and direct metaphor for spiritual healing. Taking all of these into consideration, with the help of the narrative of the Modern Primitives, I sought to understand the way in which, for many individuals, the brutal destruction and modification of skin and flesh becomes an act of creation, of reconstruction and life-affirmation. If we allow ourselves to reconsider our cultural taboos surrounding self-mutilation in a religious context, we begin to see that there may be a stronger, deeper connection between spiritual self-mutilation and pathological self-harm than we can realize, without taking a closer look at the roots of both.
- Presenter
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- Ho Wing (Andy) Chan, Sophomore, Bioengineering
- Mentor
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- Narendra Singh, Bioengineering
- Session
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- Commons East
- Easel #75
- 12:45 PM to 2:15 PM
Artemisinin (ART) is a sesquiterpene lactone (three rings chemical structure), derived from the plant Artemisia annua. Several studies have shown significantly higher cytotoxicity to cancer cells compared to normal cells. However, the mechanism of this is still in debate. The majority of researchers claim that ART reacts with intracellular iron in cancer cells to generate free radicals (species that contain unpaired valence electrons) which are responsible for the cytotoxicity. A recent finding showing ART inhibits cancer cell growth through inhibiting a protein has raised questions about the free radical mechanism for ART to inhibit growth of cancers. We hypothesize that the endoperoxide bridge (two oxygen atoms joined by single bond in a ring structure) in artemisinin forms free radicals by reacting with intracellular iron in cancer cells. To confirm our hypothesis, Molt-4 human leukemia and MDA-MB-231 human breast cancer cell lines will be treated with Deferoxamine (DX) along with Artemisinin. DX is an iron chelating agent, a chemical that could eliminate the iron in cancer cell. Our research shows that the cytotoxicity of ART is DX concentration dependent, lower concentrations (10 µM to 30 µM) reduce the cytotoxicity while higher concentrations (50 µM to 100 µM) increase it. Thus, our results show that lowering iron (to certain levels) by DX inhibits the cytotoxicity of ART. Furthermore, we have also performed experiments about the effect of phenyl-alpha-tert-butyl nitrone, PBN, an antioxidant, on ART anticancer mechanism (data not published). It is our understanding that antioxidant could inhibit the ART anticancer effects. After comparison, we found that the inhibitory effect of DX on ART cytotoxicity is the same as that of PBN. In conclusion, our preliminary results show that iron is necessary for the cytotoxicity of ART and it is free radical mediated.
- Presenter
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- Han Lian Chang, Senior, Economics, Political Science (Political Economy)
- Mentor
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- Adrian Sinkler, Political Science
- Session
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- Commons West
- Easel #36
- 12:45 PM to 2:15 PM
My research examines the increasing trend in the illicit use of prescription stimulants such as Adderall, Ritalin and Vyvanse among college students in the last 10 years and seeks to provide means to evaluate the phenomenon. One of the objectives of this study is to identify one of the four analytical perspectives in drug policy analysis (social deviance, rational choice, constructivism and realism) that best explains the pattern that is heavily featured in the literature view. Prior researches indicate 3 main positive indicators among the most common abusers: gender, ethnicity and membership in the Greek system. The constructivist approach, after careful consideration, appears to be most appropriate to further dissect the phenomenon. The approach suggests that individual behavior is fundamentally influenced by socially constructed norms. If individual behavior is indeed a product of social constructed norms, then one should hypothesize on the shift in value structures in the last decades that would have lend itself to the phenomenon. The findings from this paper would have multiple implications to policymakers as it was estimated that the number of people abusing amphetamine-type stimulants might soon exceed the number of people abusing opiates or cocaine combined. The methodology in consideration for this research is by utilizing longitudinal methods to compare panel data that is available through the National Institute on Drug Abuse, National Institutes of Health, The System to Retrieve Information from Drug Evidence (STRIDE) database, Monitoring the Future study by the University of Michigan, The National Survey on Drug Use and Health (NSDUH), Youth Risk Behavior Surveillance System (YRBSS), etc. With the data, I intend to construct an econometric model (difference in difference study or linear regression model) to outline the determinants among the samples and pinpoint the factors that are statistically significant in order to verify my hypothesis.
- Presenter
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- Yayun Chen, Senior, Bioengineering Mary Gates Scholar
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
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- Commons East
- Easel #63
- 12:45 PM to 2:15 PM
Annually, an estimation of 1.7 million people in the U.S suffer from traumatic brain injury (TBI), in which 50,000 people dies and another 85,000 people survive with long term disabilities. Moreover, TBI is reported to be the most common combat-related injury and accounts for 25% of combat casualties. CT and MRI are the current diagnostic tools for TBI, but due to their bulky size and complicated interpretation procedures, prevalent implementation of the devices is limited in undeveloped areas and near the battle field. Consequently, a size deployable diagnostic tool that is able to present quantitative evaluation of TBI is needed. The purpose of the project is to optimize an ultrasound elastography machine for detection and classification of mild and moderate TBI based on the theory that abnormal brain elasticity will be observed in presence of hemorrhage and edema. The goal was achieved in three steps: post-processing and stiffness maps were first generated in MATLAB for breast phantom to test and ensure the feasibility of coding, then data collected from moderate TBI rat brains were fed into the code with modified parameters to generate brain elasticity maps highlighting areas of damage, finally elasticity maps were be constructed for mild TBI rats. All the brains were imaged in alginate of same impedance. The quantified elasticity values in moderate and mild TBI brains allow classification of injury levels; the accuracy of constructed images will be ensured by comparisons between TBI, control and histology results. Successfully optimized ultrasound elastography machine displays quantitative analysis of brain elasticity which simplifies diagnostic procedures. Furthermore, implementation of the device in hospitals and battle fields enables early TBI detection, which will potentially reduce TBI-related deaths, lower TBI-related treatment costs and greatly enhance residents’ life quality.
- Presenter
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- Wei Shan Chin, Senior, Chemical Engr: Nanosci & Molecular Engr, Bioresource Science and Engineering
- Mentors
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- Rick Gustafson, Environmental & Forest Sciences
- Jordan Crawford, Environmental & Forest Sciences
- Session
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- MGH 241
- Easel #148
- 12:45 PM to 2:15 PM
Lignin serves as the natural glue that holds plant fibers together. It constitutes roughly 15 to 30 percent of cellulosic biomass weight. Lignin is the second most abundant natural polymer on earth. Despite lignin’s ample availability across the globe, it has largely been discarded as waste or burned as low value fuel; especially in the pulp and paper industry. Lignocellulosic biomass based biorefineries typically involve substantial capital cost with many negative externalities such as biomass and crude oil price fluctuation as well as changes in government policies (tax deduction, government-backed loans, subsidies, etc.). Therefore, producing added value fuels and chemicals from lignin, the major biomass pretreatment by-product, via commercially viable routes is essential to increase the profitability and the sustainability of these biorefineries. One of the leading biorefinery developers based in Colorado, ZeaChem, is currently investigating the possibility of producing hydrogen gas for their ethanol production by gasifying lignin residues. This research project focuses on modeling the lignin gasification process (using Aspen Plus, a commercial process simulation software) and determining the techno economic feasibility of producing hydrogen from lignin residues. The research approach is explained and some of the research findings - including the hydrogen gas yield, overall mechanical energy and heat consumption, optimum operating conditions, and capital cost - is presented.
- Presenter
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- Samantha Joan (Samantha) Chisholm, Senior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #4
- 12:45 PM to 2:15 PM
I am interested in the dynamics of injury in sports culture. Are there social consequences of injury for athletes undergoing treatment? If so, what are these social repercussions? In the culture of sports, athletes are many times expected to perform above a reasonable level. Mistakes, failure, and imperfection in sports are not accepted or supported. Injury is categorized as imperfection in our culture surrounding sports despite it being something that most individuals face at some point in their career. I expect there to be substantial social consequences for injured athletes. In a study looking at collegiate athletes who suffered a severe injury called "Transitioning out of Sport: the Phycosocial Effects of Collegiate Athletes' Career-Ending Injuries", positive and negative social consequences were found to be incredibly influential in the lives of the athletes involved in the research (Stoltenburg et al, 2011). My research methods include interviews, discourse analysis, and archival support. This subject is important because if there are negative consequences, coaches and advisers to athletes can be aware of these factors and emphasize the importance of pushing athletes to invest in multiple interests. More effort may be needed to create environments and systems that support injured athletes. Whether this research draws awareness and slowly changes social discourse on injury within an athletic arena, or initiates action and forms foundations for structures such as support groups for injured athletes, I believe it will implement positive change.
- Presenter
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- Sang Hyun (Sang) Cho, Senior, Environmental Science & Resource Management (Restoration Ecology & Environmental Horticulture)
- Mentors
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- Soo-Hyung Kim, Environmental & Forest Sciences, UW, College of Engineering
- Hyungmin Rho, Environmental & Forest Sciences
- Session
-
- MGH 241
- Easel #152
- 12:45 PM to 2:15 PM
Atmospheric carbon dioxide, the primary greenhouse gas associated with climate change, has been rising steadily since the beginning of the industrial era. Most C3 plants are likely to benefit from higher concentrations of CO2 which is the substrate of photosynthesis. However, with more carbon dioxide available to photosynthesize, the growth of plants is often limited by other resources: notably, nitrogen. Recent research with specific strains of endophytes, bacterial or fungal organisms living within plants, shows positive symbiosis to supply the needed nitrogen to the host plants in elevated carbon dioxide scenarios. In this study, medium grain M206 rice (Oryza sativa) was inoculated with 9 strains of endophytes from native poplar (Populus trichocarpa) and willow (Salix sitchensis). The inoculated rice and uninoculated control were then put in CO2 enrichment chambers to replicate current atmospheric and future elevated levels of carbon dioxide. I hypothesize that 1) the endophytes will give the rice plants an advantage in both ambient and elevated chambers when compared to the control because of the biologically fixed nitrogen the endophytes will provide, and 2) this advantage will be more pronounced in elevated CO2 than in ambient CO2. Tests concerning photosynthetic capacity, water use efficiency, and overall biomass will be used to determine significant differences. If conclusive, endophytes may be a means to capitalize on the benefits of increasing atmospheric CO2 while curbing the negative impacts of excessive nitrogen fertilizer use by modern cropping systems on climate change.
- Presenter
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- Jennifer Lynn (Jen) Choi, Senior, Bioengineering Amgen Scholar, Mary Gates Scholar
- Mentors
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- Suzie Pun, Bioengineering
- Julie Shi, Bioengineering
- Session
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- Commons East
- Easel #77
- 12:45 PM to 2:15 PM
One of the major intracellular barriers to non-viral gene delivery is degradation through the endosomal/lysosomal pathway. To overcome this barrier, pH-sensitive polymers that swell in acidic pH and ultimately disrupt the endosome can be designed to escape these compartments. Previously, the Pun lab developed HPMA-oligolysine copolymers that have transfection efficiencies approaching that of polyethylenimine (PEI), the gold standard for transfection. In order to increase the copolymers’ transfection efficiency, oligohistidines were incorporated into the copolymer in both statistical and block architectures to impart pH-sensitivity. Transfection studies with these two copolymers showed that statistical incorporation of oligohistidine increased transfection efficiency, while block incorporation did not increase transfection efficiency. To determine if structure-function differences affected cellular uptake and endosomal buffering, we performed uptake inhibitor and endocytic buffering inhibitor studies. Through these studies, we found that both copolymer geometries preferred non-clathrin coated caveolae uptake pathways, and that they differed in endosomal buffering capabilities. The statistical copolymer showed increased endosomal buffering capacity, which was consistent with the overall higher transfection efficiency of the statistical copolymers over the block copolymers. From these two studies, we are better able to understand the relationship between structure and function in gene delivery using polymers.
- Presenter
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- Stephanie S (Stephanie) Chu, Senior, Bioengineering
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
-
- Commons East
- Easel #69
- 12:45 PM to 2:15 PM
Traumatic brain injury (TBI) is a common injury sustained by soldiers and requires immediate and sensitive brain imaging in order to diagnose the extent of damage. Currently, conventional methods of brain imaging such as computed tomography and magnetic resonance imaging are not field-deployable and immediately available on the battlefield. Tissue pulsatility imaging (TPI) is a technique that measures the natural pulsatile motion of tissue as a result of blood flow. Preliminary brain tissue samples of mice with TBI observed under widefield microscopy have shown increased mitochondrial accumulation at the site of injury relative to comparable sites in the hemisphere contralateral to injury, suggesting that TBI disrupts normal mitochondrial migration patterns. It is hypothesized that biological responses such as this, as well as the development of hemorrhage and edema, cause a change in brain tissue pulsatilities of TBI animals that can be detected by TPI. In this project, TPI by ultrasound will be used to image the brains of mice with acute and chronic (24-hour) TBI to determine whether this method of ultrasound imaging has the potential to be used for initial detection of TBI. Animal trials with both bilateral and hemispheric cranial windows will be used to study TPI patterns in the brains of these mice. Among the issues we will address include the effects of the skull on image resolution. Subsequent data analysis and device parameter adjustment should increase the resolution of images in order to optimize a design for an ultrasound device based on imaging tissue pulsatility that can accurately detect TBI and may eventually serve as a field-deployable brain imaging device.
- Presenter
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- Lorelei Clark, Sophomore, Biology, Mathematics, Seattle Central College
- Mentors
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- Shawn Larson, Seattle Aquarium
- Angela Smith, Seattle Aquarium
- Session
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- MGH 241
- Easel #170
- 12:45 PM to 2:15 PM
In aquariums and zoos across the world marine mammals are among the most popular exhibits. Caretakers strive to provide the least stressful and natural environments for the animals. Analysis of (steroid) hormones in excrement has proven to be an effective, non-invasive method. It allows animal keepers to monitor physiological health associated with reproduction and the stress response in captive animals. Prolactin (PRL) is a non-steroidal, non-tropic peptide hormone most commonly associated with milk production in nursing females. However, it has a multitude of normal physiological functions such as: regulation of the immune system, osmotic balance, angiogenesis, an indicator of parental care (in both males and females), sexual maturity in males, and near-term pregnancy in females. Chronically high or low levels of PRL have been associated with a number of ailments. For instance, impotence reduces the secretion of estrogens and testosterone. To date, no studies have been documented on prolactin PRL levels in captive northern fur seals, (Callorhinus ursinus), harbor seals (Phoca vitulina), or sea otters (Enhydra lutris). Using an enzyme-immunoassay (EIA) kit, previously tested only in human and elephant serum analysis, we investigated PRL levels of several samples collected from captive marine mammals (Northern fur seal blood serum, harbor seal saliva, and sea otter urine/fecal samples). Due to the helical structure of PRL, fecal samples were not expected to survive intact after transit through the digestive tract; therefore, were not expected to produce positive results. Here we report preliminary results of the EIA PRL assay on several different types of samples, as well as several longitudinal samples from the same individual, to show significant changes in this hormone over time. If detectable in urine, fecal matter, and/or saliva, this assay could prove to be a useful non-invasive method for determining health in captive marine mammals.
- Presenter
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- Nathan Scott (Nate) Clark, Senior, Biology (Physiology)
- Mentor
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- Stephen Thielke, Psychiatry & Behavioral Sciences
- Session
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- Commons West
- Easel #19
- 12:45 PM to 2:15 PM
Experimental studies have suggested that pain and dyspnea (shortness of breath) may involve the same affective experience. This association has not been explored in large community samples. We analyzed data from Cohort 12 of the Medicare Health Outcomes Survey, which measured subjective health status in 275,000 Medicare Managed Care recipients in 2010 and 2012. Dyspnea was defined by aggregating three questions (shortness of breath at rest, while walking one block, and while climbing stairs). Pain was measured by a question about how much pain interfered with normal work inside and outside the home during the last month. Both measures were dichotomized as high and low / none. We produced descriptive statistics to characterize the overlap of pain and dyspnea at baseline. We created regression models to measure the strength of the association of pain with dyspnea, adjusting for age, sex, race, education, and three potential medical causes of dyspnea (CHF, obesity and asthma). We estimated the likelihood of dyspnea and pain co-occurring at the two measurement points two years apart. 22.2% of participants without dyspnea had pain and 69.9% of those with dyspnea had pain. In an adjusted regression model, participants with dyspnea were 8.3 times more likely to have pain than those without dyspnea. Pain was strongly associated with the onset and the persistence of dyspnea. In this large sample of Medicare recipients, pain and dyspnea were very strongly associated, to the degree that they may represent different facets of the same experience. These results confirm experimental studies about the affective experience of both symptoms. These findings might help clinicians to appreciate better how patients experience pain and dyspnea. Additional research is needed to understand the exact mechanisms by which pain and dyspnea co-occur, and other risk factors for them.
- Presenter
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- Janet M. Cook, Senior, Interdisciplinary Arts & Sciences (Environmental Studies), UW Tacoma
- Mentor
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- Cheryl Greengrove, Interdisciplinary Arts & Sciences (Tacoma Campus)
- Session
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- MGH 241
- Easel #146
- 12:45 PM to 2:15 PM
Three distinctly different beach environments can be observed at Owen Beach in Tacoma, Washington; a natural beach environment, a partially modified beach environment and a fully engineered beach environment. Each part of the beach has a unique morphology and profile. This study was designed to analyze these differences and determine the effects, if any, that the anthropogenic modifications have on the slope, change in elevation and sediment characteristics along this beach over the course of a year. The beach slope and change in elevation were measured monthly starting May 2012 at three points along the beach face from each type of environment using a tape measure and Brunton compass. Sediment samples were taken from the same points and measured using a Particle Size Analyzer or grain size chart. Sketches were made of the beach profile that include tide line, landscape, data points, sediment deposition, high tide line, and modifications. Preliminary analyses of data shows that the anthropogenic modifications have a direct effect on the morphology and profile of the beach. The fully modified portion has been more static than the other two parts with larger particles and less change in slope. The modified portion has smaller particles along its shore and its slope has been more dynamic than the fully engineered portion of the beach. The natural portion of the beach is the most dynamic with much smaller particles along its shore and a larger change in slope throughout the year. It is important to study the effect that human engineering has on natural beach environments so that we can fully assess its impact on and applicability for managing coastlines for residential, commercial and recreational use in our communities.
- Presenter
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- Erin Yvette (Erin) Cote, Senior, Linguistics, Biology (General) Mary Gates Scholar
- Mentors
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- Veronica Di Stilio, Biology
- Kelsey Galimba, Biology
- Session
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- MGH 241
- Easel #159
- 12:45 PM to 2:15 PM
The first floral mutations ever documented, double flowers have been prized for centuries for their beauty. Double mutants known as ‘Shoaf’s Double’ and ‘Cameo’ are present in the species Thalictrum thalictroides, a member of the buttercup family. The purpose of this research is to determine the genetic mutation causing these phenotypes. We predicted that a mutation in a C-class floral organ identity gene would cause the homeotic transformation of stamens and carpels to petalloid sepals in this species. C-class genes are also involved in floral determinacy, the termination of growth in the flower meristem, which is why double flowers appear to have a second flower nested inside the first. As expected, the expression of the C-class gene AGAMOUS1 (AG1) was greatly reduced in our mutants. To pinpoint the mutation we first sequenced the coding region, the part of a gene that becomes a protein. Finding no changes from wild type I further sequenced the entire genomic locus. In AG1, the first intron is known to have regulatory function. I found evidence of the action of a DNA transposable element in both mutants. In “Shoaf’s Double” a Mutator element has inserted itself into the first intron of AG1, potentially disrupting its function. In “Cameo” there is a ‘footprint’ present in the same site, which indicates the same element may have jumped out, deleting a necessary section of the gene. These results show the presence of at least one active DNA transposon in this species, capable of causing a phenotype due to disruption of a regulatory region. This transposable element could potentially be induced to jump and create new mutant lines. Similar mutations could potentially underlie other popular double flower cultivars, such as those found in roses, camellias and carnations.
- Presenter
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- Nathaniel Keeler (Nathaniel) Coulson, Senior, Bioengineering Mary Gates Scholar, NASA Space Grant Scholar
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
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- Commons East
- Easel #68
- 12:45 PM to 2:15 PM
The insertion and placement of an external ventricular drain (EVD) addresses two important neurological problems with more than two hundred fifty thousand procedures per year. For example, ventriculostomies are performed when intracranial is elevated and either is immediately dangerous or will not respond to drug therapies. The success rate of EVD placement is sufficiently low to cause concern and few systems exist for guided assistance in EVD placement. We propose a handheld, disposable, ultrasound guided ventricular catheter to assist neurosurgeons in precise and accurate EVD placement. Utilizing existing catheter designs, we have replaced the current guide wire with one that contains a small (one mm in diameter) ultrasound transducer at the tip. The ventricles have a set of acoustic properties significantly different from brain tissue, allowing us to detect them with ultrasound. We processed the ultrasound backscatter signal from the ventricle walls using custom electronics to give feedback to the neurosurgeons while they are directing the catheter. We have collected initial data that supports the feasibility of this device. Results to date in porcine models have demonstrated an ability to detect ventricles and assist in the precise guidance of the catheter into the desired lateral ventricle. Outcomes have been repeatable for practicing neurosurgeons over all trials in five experiments and for others over 8/10 attempts in three experiments using a Sonosite MicroMaxx to verify accurate EVD placement. Moving forward we will incorporate pulsitility and Doppler imaging modalities to decrease the margin of error for false positive ventricle detection. We aim to increase the reliability of accurate EVD placement in both emergency room and operating room situations while providing a product that is less expensive and more accessible than current guided systems.
- Presenter
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- Melanie Jean Coyne, Junior, Chemical Engineering
- Mentors
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- Hong Shen, Chemical Engineering
- Helen Chen, Chemical Engineering
- Session
-
- Balcony
- Easel #119
- 12:45 PM to 2:15 PM
With the proliferation of autoimmune diseases and cancer it is of increasing importance to discover new ways to utilize nanoparticles as carriers for the delivery of therapeutic agents. To achieve this aim, the trafficking of nanoparticles within dendritic cells must be better understood. When cells uptake foreign material, an innate immune response is triggered through the activation of pattern recognition receptors such as toll-like receptor 9 (TLR9). TLR9 ligands follow one of two pathways when introduced into a cell - one trafficking through early endosomes, the other through late endosomes. This research analyzes the intracellular trafficking of TLR9 ligands through the image analysis of dendritic cells. Using an imaging software, ImageJ, it is possible to plot the relative intensities of fluorescently labeled polystyrene nanoparticles coated with TLR9 ligands CpG 2216 or CpG 1826 as well as late endosomal markers Rab7 or LAMP2. By analyzing the co-localization of these intensity profiles, it can be determined if there is recruitment of the late endosomal marker to the endocytic vesicle of the nanoparticle. The recruitment analysis confirms which intracellular pathway is taken by these nanoparticles. A statistical analysis of a large sample size of nanoparticles will be performed. This research will shed light on how nanoparticles can be used as drug carriers by supplying critical information about the intracellular fate of nanoparticles coated with TLR9 ligands.
- Presenter
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- Asalemo Michael (Asalemo) Crawford, Junior, Anthropology
- Mentor
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- Holly Barker, Anthropology
- Session
-
- Commons West
- Easel #5
- 12:45 PM to 2:15 PM
Social media has had a history of creating facades of cultures, and this is especially true in the scope of sports. My question then is what is the effect of social media’s portrayal of Pacific Islander athletes on the cultural image of Pacific Islander students? For many higher education campuses, Pacific Islander (PI) student populations are vastly underrepresented in the general population spectrum. Yet there exists on sports teams a vast overrepresentation of Pacific Islanders, especially in football. The issue then is the effect this has on the image of Pacific Islanders, where we are seen as either "savage" or "barbaric" but rarely academic. My research will address this issue and see if the underlying misperception stems from social media. I will also analyze the effect this portrayal has on PI student athletes. The methods I chose to analyze the issue are interviews of PI athletes, photovoice and social media analysis. Through photovoice I will contrast how social media interprets the image of PI’s as and how PIs themselves view their cultural heritage. From these methods I anticipate a qualitative understanding of how social media has propagated a false image of PI culture to the general public. Then I hope to address how we as a society can oppose this image through more accurate education of PI culture.
- Presenters
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- David Daniel (David) Dever, Senior, Bioengineering Mary Gates Scholar
- Martin Wei Biao Suarez, Senior, Bioengineering
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
-
- Commons East
- Easel #67
- 12:45 PM to 2:15 PM
Traumatic brain injury (TBI) is a major issue in warzones and it is often misdiagnosed and therefore mistreated in the field due to unavailability of accurate imaging technologies and subjectivity of motor response tests. Soldiers who experience TBI and are not properly treated often deal with severe mental, physical, and emotional consequences for their remaining lifetime. As such, there is a need for a field-deployable modality for the detection of TBI. Proposed here is the use of ultrasound vibro-acoustography for detection, which has been shown to measure differences in mechanical properties of materials using intense focused ultrasound (iFU) to vibrate the material and record the acoustic emissions. I am working to quantify the emission differences of healthy and damaged tissue through in vivo rat testing. By optimizing ultrasound parameters and experimental protocol, my work will support the end-goal design an affordable and portable device for TBI detection away from modern medical centers.
- Presenter
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- Tanner Chas (Tanner) Dixon, Junior, Neuroscience
- Mentors
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Anna Kresse, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
-
- Commons West
- Easel #34
- 12:45 PM to 2:15 PM
Event related potentials (ERP) are electrophysiological responses of the brain measured during an electroencephalogram (EEG). The Mismatch Negativity (MMN) is an ERP component that occurs as a result of the brain detecting a deviant sound among a sequence of standards. It is represented by a negative peak in the fronto-central region of the scalp with latency 100-250 ms after onset of the abnormal stimulus. Previous studies have shown that the MMN is reduced in children with autism spectrum disorders (ASD) relative to typically developing children. It has been suggested that this indicates atypical automatic auditory processing in ASD. Other research has found abnormal MMN activity in schizophrenia patients as well. These studies have found an association between MMN activity and test measures of social function in individuals with schizophrenia. It has been theorized that impairment in auditory detection present in schizophrenia (as evidenced by a reduced MMN) may have downstream effects on certain facets of social cognition. No known work has yet been done to assess the same association in ASD. This study investigated the relationship of the MMN with social skills in individuals with ASD. In this study, EEG was recorded from children and adolescents with and without autism while they listened to auditory stimuli consisting of a standard sound ("ba") and deviant sounds ("da," "bi") to elicit an MMN. Parents reported on children’s social adaptive behavior in the Vineland assessment. The aims of this study are to (1) replicate previous findings that individuals with ASD have a reduced MMN relative to typically developing individuals, and (2) explore the relationship between the MMN and social behavior in children with ASD and typical development, as measured in the Vineland. A strong association may shed light on the sensory involvement in typical social functioning.
- Presenter
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- Eric Do, Senior, Bioen: Nanoscience & Molecular Engr Levinson Emerging Scholar, Mary Gates Scholar
- Mentor
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- Kim A. Woodrow, Bioengineering
- Session
-
- Commons East
- Easel #48
- 12:45 PM to 2:15 PM
We have developed nanoparticle-based combination antivirals (ARVs) as an effective strategy for oral or topical HIV prevention. Currently, most candidate-microbicides consist mostly of gels, which have demonstrated poor efficacy in clinical trials. Studies have supported the successful impact of highly active antiretroviral therapy (HAART) as a standard of care for HIV/AIDS affected individuals, which has motivated the investigation of the topical delivery of combination antiretroviral drugs. The proposed work has the potential to address the delivery challenges brought upon by the diverse classes of ARV drugs. The primary appeal for this approach lies in the combination delivery of drugs with different properties and mechanisms of actions to minimize chances of resistance and improve efficacy. Here we show that individual ARV drugs can be encapsulated into poly (lactic-co-glycolic acid) PLGA nanoparticles with sizes ranging between 250-300 nm, zeta potentials of about ≥-20 mV, and high drug loading and encapsulation efficiency, as measured by dynamic light scattering (DLS) and high-performance liquid chromatography (HPLC), respectively. Furthermore, we found that these ARV drug-encapsulated nanoparticles demonstrated potent anti-HIV activity against HIV-1 BaL infection of TZM-bl cells. The effect of combination delivery of these ARV drug-encapsulated nanoparticles was evaluated to identify synergistic drug combinations and favorable drug-drug interactions. Our results demonstrate the potential for this drug delivery system as an effective strategy for HIV prevention. Successful outcomes of this endeavor could have profound implications on microbicide research and a potentially viable female-controlled prevention method for HIV.
- Presenter
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- Marie Ellen Eberlein, Senior, Bioengineering, Swedish
- Mentor
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- Barry Lutz, Bioengineering
- Session
-
- Commons East
- Easel #50
- 12:45 PM to 2:15 PM
The control of infectious diseases in low-resource settings continues to be impacted by the limited availability of low-cost, easy to use diagnostics. However, even in developing nations, smart phones are common and can be used as “instruments” to control diagnostic devices. My senior capstone project aims to use a smart phone to input a sound wave into a microfluidic card and measure a sound wave coming out of the card to determine whether an analyte—the chemical that indicates whether a person is infected—is present in the sample. This is done by creating a network of fluid channels that can be modeled as an electrical circuit containing the fluidic equivalent of resistors, inductors, and capacitors (RLC circuit). When the sound wave is input to the system, it causes the fluid to oscillate and has a resonant frequency that is dependent on the characteristics of the system (the resistance, inductance, and capacitance). The goal is to cause a change in the fluid resistance, fluid inductance, or fluid capacitance through a chemical reaction (e.g. the creation of a bubble would change the capacitance or a change in viscosity would change the resistance). This change in a characteristic shifts the resonant frequency of the fluid circuit, allowing the presence of the analyte to be recognized. This project seeks to integrate a means of detection (like a microphone) into the diagnostic card to measure the analyte-dependent resonant frequency. This card would then be used as the platform for a measurement of blood clotting. Completion of this project would take the system one step closer to bringing simple and effective diagnostic platforms to developing nations.
- Presenter
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- Paul Martin (Paul) Ellenbogen, Senior, Computer Science, Mathematics
- Mentors
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- Michael Hoffman, Genome Sciences
- William Noble, Computer Science & Engineering, Genome Sciences
- Session
-
- MGH 241
- Easel #165
- 12:45 PM to 2:15 PM
Although every cell in the human body has nearly the same DNA sequence, there are many different cell types performing different functions; for example, lymphoblast cells which differentiate into white blood cells or endothelial cells which provide a lining throughout the human vascular system. But cells do not always function as they should, for example, overproduction of white blood cells can be caused by lymphoblastic leukemia, a type of cancer. I intend to use data on the sensitivity of parts of the genome to deoxyribonuclease (DNase) digestion to explain the differences in cell behavior. Regions of the genome structure that are hypersensitive to DNase have already been shown to affect gene expression. I want to determine if portions of the genome which are mildly sensitive, or mesosensitive, to DNase play a role in cell differentiation. My hypothesis is that DNase can identify large scale regions, on the order of thousands of base pairs, that harbor cell type specific genes. I used Segway, software which uses a dynamic Bayesian network, to segment the genome based on DNase sensitivity data into regions of low sensitivity, mesosensitivity, and hypersensitivity on six different cell types. From my segmentations I removed the hypersensitive regions from considerations, and compared the low and mesosensitive regions to gene expression data. I found that regions Segway labels mesosensitive had higher levels of expression than low sensitivity regions. I expect to find that many of the regions responsible for cell type specific behavior are mesosensitive. If this is the case, I hope the results will be robust enough such that anyone with access to DNase data can determine what genes are active in a population of cells, enabling them to better predict the behavior of the cells. In furthering our understanding of gene regulation, we may better understand diseases such as leukemia.
- Presenter
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- Alexander (Alex) Esibov, Senior, Bioengineering Mary Gates Scholar
- Mentors
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- Carol H. Miao, Pediatrics
- Misty Noble, Bioengineering, Seattle Children's Research Institute
- Session
-
- Commons East
- Easel #54
- 12:45 PM to 2:15 PM
Ultrasound (US) and microbubbles (MBs), as tools for gene transfection, have promising implications for gene therapy. Through permeation, US facilitates the diffusion of a gene or drug from the capillaries into the cell. Binding of the gene or drug to the MBs can further enhance the delivery efficiency to the cell, and when exposed to US, the MBs cavitate, allowing the gene to diffuse into its target destination. Optimal US parameters (intensity, exposure time, central frequency) and MB characteristics (concentration, size, distribution, stability) are interdependent with regards to transfection and cavitation optimization, and thus the optimization of each individual parameter is important. Preliminary data has indicated that the optimal intensity and exposure time for US is 2 W/cm2 for 3 minutes. However, optimizing US frequency has not been widely explored. The goal of this project is to investigate the effect of US frequency on MB cavitation, with both pure MBs and DNA-bound MBs . In order to do this, the following areas have been completed or are in the process of being completed. 1. A method has been designed to isolate home-made MBs by size; 2. A novel set-up to record the interaction of the US with the MBs with a hydrophone has been created and tested. The signals must be collected and processed with a written MATLAB program; 3. The results must be applied to in vitro US transfection with MBs of human embryonic kidney 293 (HEK 293) cells to demonstrate the effect of frequency on transfection results. By expanding research in US-mediated gene therapy with MBs, it is the hope that one day this method will be advanced towards clinical application as a means of non-invasive, localized, and efficient gene delivery.
- Presenter
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- Madison Claire (Madi) Feil, Senior, Psychology, Neuroscience Undergraduate Research Conference Travel Awardee
- Mentor
-
- David Perkel, Biology, Neurobiology & Behavior, Otolaryngology - Head And Neck Surgery
- Session
-
- Commons East
- Easel #80
- 12:45 PM to 2:15 PM
Vesicular Glutamate Transporters (vGluts) are proteins that package glutamate into vesicles prior to synaptic transmission. Three isoforms have been identified in mammals (vGlut-1-3), with 1 and 2 showing a mostly complementary pattern of expression, and 3 co-localizing in a small number of cells with both 1 and 2. Knockout mice for the vGlut1 gene die shortly after weaning, indicating a crucial role for vGlut1 in development. Intriguingly, avian genomes contain no vGlut-1 orthologs, despite the fact that lizards, a common ancestor of both mammals and birds, have orthologs of both vGlut-1 and -2. The fact that birds function without vGlut1 suggests there may be an increased functional role for vGlut2 in the avian brain. To further demonstrate the presence and potential role of vGlut2 in avian pallial circuitry, we used immunocytochemical methods to study the brain distribution of vGlut2 protein in zebra finch. To confirm the specificity of antibodies to vglut2, we first performed co-localization of anterograde tracer with vGlut-2 in known glutamatergic terminals in RA that originated from pallial song nucleus HVC. Electron microscopy further confirmed that labeling was restricted to synaptic terminals containing vesicles, and in situ hybridization was used to confirm the presence of mRNA in somata. We found that a large number of vGlut2-positive cells are present throughout the zebra finch pallium, and also found evidence for vGlut-2 positive synapses in three different song nuclei (nucleus HVC, Area X, and robust nucleus of the arcopallium), which were imaged and analyzed for size, and the potential identity of post-synaptic elements. Our results are consistent with the notion that avian vGlut2 has largely taken over vGlut1 functions. We believe our study contributes important facts to the long disputed evolutionary relationship between the avian pallium and the mammalian cortex.
- Presenter
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- Samantha Jo Fix, Junior, Pre Engineering NASA Space Grant Scholar
- Mentor
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- Erika Harnett, Earth & Space Sciences
- Session
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- Balcony
- Easel #96
- 12:45 PM to 2:15 PM
The Moon does not have a dipolar magnetic field, like that of the Earth. Instead, the Lunar surface has areas of magnetized crust called magnetic anomalies. Many of these magnetic anomalies are coincident with features called lunar swirls - regions with high-albedo or high-reflectance material. As many of these lunar swirls often appear in the same location as areas of relatively intense magnetic fields, one of the leading hypotheses explaining the formation of the lunar swirls is that the surface is shielded from the surface darkening solar wind by the magnetic anomalies. We seek to further understand the connection between the visual high albedo and the magnetic anomalies by creating three-dimensional models of the magnetic fields and particle deflection around well-known lunar swirls. We do this through the use of a three-dimensional particle tracking program. The particle tracking program simulates solar wind interacting with the magnetic field and determines the final location of the solar wind particles on the surface of the Moon. This work focuses on the results for simulations of the Mare Ingenii swirl region. Preliminary results show that the particles are in fact deflected, and as expected the smaller electrons are more highly deflected. Better understanding of the origin of the Lunar swirls not only allows us to gain insight into the process of space weathering and magnetic shielding but can also offer clues for methods to mitigate the harmful effects of solar wind and particle radiation during human space travel and at lunar or Martian human colonies.
- Presenter
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- Erin Fox, Sophomore, atmospheric science, astronomy, Seattle Central College
- Mentor
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- Dargan Frierson, Atmospheric Sciences
- Session
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- MGH 241
- Easel #142
- 12:45 PM to 2:15 PM
Global Climate Models (GCMs) are used for predicting numerous aspects of the climate system for storm prediction, patterns and cycles, and understanding of the atmosphere. These models, however, have problems in accurately predicting precipitation in certain areas which is what my research will be focusing on. The double intertropical convergence zone (ITCZ) problem in one of the major flaws in current GCMs which results in over-predicting precipitation over the southern tropics, a region that is mostly water, by producing two ITCZs straddling the equator. Recent studies have led to the conclusion that cloud biases over the Southern Ocean in current GCMs explain the hemispheric asymmetry of tropical precipitation, and are thus responsible for the double ITCZ problem. This study looks to find the source of the error by reparameterizing shortwave cloud radiative forcing over the Southern Ocean in order to account for the greater cloud coverage observed, which is not represented in the GCMs. To accomplish this I manipulate the cloud parameterization in the Geophysical Fluid Dynamics Laboratory's aquaplanet AM2 model, which models the atmosphere of a water covered planet. The results of this study will lead to more accurate climate modeling ability over the water-covered portions of Earth, and will specifically aid in our understanding of precipitation predictions over the southern tropics.
- Presenter
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- Taylor Eliza Gardiner, Senior, Microbiology Howard Hughes Scholar, Mary Gates Scholar
- Mentors
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- Joseph Mougous, Microbiology
- Seemay Chou, Microbiology
- Session
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- Commons East
- Easel #56
- 12:45 PM to 2:15 PM
The export of signals is a vital aspect of bacterial communication with its environment and it was recently found that Gram-negative bacteria can send signals directly to neighboring bacteria via the type VI secretion system (T6SS). The bacterial T6SS translocates antibacterial toxins into neighboring bacterial cells and provides a means for bacteria to compete in their environment. Bacteria can also target their own cells with the T6SS but are protected against self-intoxication by cognate immunity proteins that inactivate their partner toxins. For example, one T6-exported toxin found in Pseudomonas aeruginosa, Tse1, degrades the cell wall of the recipient cell. The cell wall provides structural support for bacteria, and degradation of this protective layer by Tse1 causes the target cell to lyse. P. aeruginosa is immune to this toxicity, however, because an immunity protein, Tsi1, in the cell wall layer of P. aeruginosa binds and inhibits T6-exported Tse1. Our lab has found that Tse1 and Tsi1 are members of a large superfamily of type VI amidase effector-immunity widely found in Gram-negative bacteria, suggesting that these T6 toxin-immunity pairs may play a major role in influencing the structure of polymicrobial communities in general. Because of the large influence the T6SS can have on polymicrobial environments, I predict the T6-toxin-immunity system could also be utilized as an antimicrobial strategy. My aim is to engineer a novel Tse1–Tsi1 toxin–immunity pair that escapes rescue by immunity proteins in naturally occurring bacteria, thus giving the engineered P. aeruginosa strain the ability to outcompete the natural wild-type strain. To do this I will use a structure-based approach in conjunction with a genetic directed evolution strategy to identify and mutate Tse1 and Tsi1 residues that play an important role in Tsi1–Tse1 recognition and inhibition.
- Presenter
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- Anupam Kumar (Anupam) Garg, Senior, Bioen: Nanoscience & Molecular Engr Mary Gates Scholar
- Mentors
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- Richard Gardner, Pharmacology
- Michelle Oeser, Molecular & Cellular Biology
- Session
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- Commons East
- Easel #45
- 12:45 PM to 2:15 PM
Ubiquitin is a protein modifier that is essential for many eukaryotic cellular processes. Attachment of ubiquitin to substrate proteins (ubiquitination) occurs in a three-step cascade that involves a ubiquitin activase, ubiquitin conjugase, and ubiquitin ligase; it is the ligase that targets substrate proteins. One challenge for the ubiquitin field is identification of substrate cohorts for ubiquitin ligases. Although ubiquitination only occurs naturally in eukaryotic organisms, we previously demonstrated that it is possible to reconstitute the ubiqutination cascade in E. coli, allowing for analysis of ubiquitination outside of its natural environment. Our project consists of the construction of a protein complementation assay, using two fragments of dihydrofolate reductase (DHFR) to detect the ubiquitination of proteins in E. coli, outside of the natural eukaryotic environment of ubiquitin. To perform the assay, I transformed all of the essential components of the ubiquitination pathway, including individual fragments of DHFR fused to ubiquitin and a substrate protein of interest, into E. coli cells. The assay tests for the covalent attachment of ubiquitin to the substrate protein through growth on selective medium, which is possible only through the combination of the separated fragments of DHFR. After construction and transformation of vectors using a known yeast ubiquitin ligase and substrate partner, I have found that ubiquitin fused to a fragment of DHFR functionally attaches to other proteins via a known ubiquitin ligase. Transformation of entire cDNA libraries into the bacterial cell in place of a ubiquitin ligase will allow for high throughput screening of ligases with homologous function as well as discovery of new ubiquitin ligase substrates. As no functional screening mechanisms presently exist, our system to efficiently screen for ubiquitin ligases and substrates provides a novel tool to address a significant challenge faced by the ubiquitin field.
- Presenter
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- Melissa C. (Melissa) Gile, Senior, Chemical Engineering, Mathematics
- Mentor
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- Jim Pfaendtner, Chemical Engineering
- Session
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- Balcony
- Easel #117
- 12:45 PM to 2:15 PM
The purpose of this study is to determine fundamental structure-solvent-property relationships in organic photovoltaic polymers (OPV’s), with the overarching goal of increasing the efficiency of OPV’s. A typical silicon-based photovoltaic plant outputs approximately 88,000 m2 of photovoltaic cells each year- about the size of 16 football fields. On the other hand, an organic photovoltaic printer will produce the same area in up to 10 hours. OPV’s are incredibly fast, cheap, and easy to produce relative to their inorganic counterparts, but fall short within the realm of efficiency; the 10% efficiency of OPV’s can hardly rival the ~40% efficiency of inorganic photovoltaic technology. If the efficiency of OPV’s can be increased, this will have a drastic impact on the competitive marketability of photovoltaic technology. This project aims at developing computational models to study the role of solvents in the self-assembly of polythiophenes during the printing process. These models are generated in GROMACS, a program that uses classical forces such as Coulombic or Van Der Waals forces, to predict how molecules will behave with time. This is problematic, however, for OPV’s, as key interactions occur on the quantum level, and new classical force fields, which are computationally very efficient, need to be altered in order to accurately calculate these interactions. A force field is being developed and refined by comparing our computational results with experimental results from the Pozzo Research Group within the Department of Chemical Engineering. Once these results are reliably consistent with each other, we can begin running simulations and gathering data regarding how OPV’s assemble in various environments. In particular, this poster explains a systematic methodology I have developed to use the GROMACS program to perform molecular dynamics (MD) simulations of single chain OPV’s in various solvents as well as simulations of bulk OPV’s in the melt state.
- Presenter
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- Kendell Gilmore, Junior, Biochemistry, Biophysics, Molecular Biology, Whitman College
- Mentors
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- Nancy Forsthoefel, Biology, Whitman College
- Dan Vernon, Biology, Whitman College
- Session
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- MGH 241
- Easel #162
- 12:45 PM to 2:15 PM
The PIRL genes are a family of nine genes discovered during the sequencing of the Arabidopsis thaliana genome, the first fully-sequenced plant genome. PIRLs are a previously uncharacterized class of plant leucine-rich repeat (LRR) proteins that are hypothesized to be important to plant development. As part of an ongoing systematic study to gain insight into PIRL functions, I examined Arabidopsis plants engineered to overexpress the PIRL9 gene. Plants containing an extra copy of PIRL9 designed to drive overexpression of the gene were identified and observed as they grew. Abnormal leaves were observed in most of these plants and stunted growth was quantified through measurements of leaf length and width, as well as primary stem height. Using qPCR, the amount of PIRL9 mRNA present in the different plants was quantified and linked to previous plant measurements. Data showed a correlation between severely stunted plant growth and overexpression of the PIRL9 gene. Significance of these results for PIRL9 function will be discussed, but further genetic and phenotypic analysis is needed to confirm and assess the effects of PIRL9 overexpression.
- Presenters
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- Alexandria Charlotte (Ali) Gingrey, Junior, Atmospheric Sciences
- David Youngjun (David) Yun, Junior, Mathematics, Astronomy, Physics: Comprehensive Physics
- Steven Joel (Steven) Brey, Senior, Atmospheric Sciences
- Adam Eric Wisch, Senior, Atmospheric Sciences
- Andrew Jarai (Andrew) Ho, Senior, Biochemistry, Chemistry
- Mentor
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- Cecilia Bitz, Atmospheric Sciences
- Session
-
- Balcony
- Easel #107
- 12:45 PM to 2:15 PM
Everyday, people's lives are affected by the weather; whether sunshine or rain, weather is a part of daily life. Extreme weather events can bring normal activities to a halt. Weather events known as "blocking" involve a pause in the of the typical passage of storms in the jet stream, causing weather systems to stay in place for lengthened periods of time. Wintertime blocking events often cause extreme cold winter temperatures over land, and data show that blocking frequency is increasing. A potential cause for this is due to sea ice loss and the warming of the Atlantic Ocean. Our investigation is of the extraordinary January 2012 blocking event over Europe. The nature of this extreme event was tested using the Weather and Research Model applied to the domain including the Western Arctic Ocean, the North Atlantic Ocean, and Europe, with a resolution of 40 kilometers. The event was simulated over the period from January 15, 2012 to February 6, 2012, with horizontal boundaries and initial conditions constrained by atmospheric observations. In a series of model integrations, we manipulated the thickness of sea ice and sea surface temperature in high altitudes and found that there is a link between thinner sea ice and warmer ocean temperatures and an increased intensity of the blocking event over Europe. This discovery allows for a better understanding of the potential impacts of melting sea ice as the climate changes.
- Presenter
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- Michael Christopher (Michael) Gross, Senior, Biochemistry, Microbiology
- Mentors
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- Zi-Jun (Zee) Liu, Orthodontics
- Susan Herring, Orthodontics
- Katherine Rafferty, Orthodontics
- Session
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- Commons East
- Easel #59
- 12:45 PM to 2:15 PM
Botulinum neurotoxin type A (BoNT/A) has been extensively used in human masticatory muscles for cosmetic reduction of large masseter muscles, relaxing the muscles and reducing pain in temporomandibular joint and muscle disorders, and decreasing loading on the mandible. Multiple applications of BoNT/A over time is a clinically routine practice to reach the treatment goal. However, it is unknown how the muscle responds to multiple neuromuscular blockages by BoNT/A, and whether or not the injected muscle shows functional recovery differently after each application. This study was designed to answer these questions. Adult New Zealand rabbits were injected 3 times either with BoNT/A (n=13) or saline (n=5) in one masseter at week 0, 12, and 24. Non-invasive surface electromyography (EMG) of bilateral masseter muscles was recorded during natural mastication 1 week before the first injection and every two weeks thereafter up to week 35. Jaw movement was video-taped and synchronized with EMG recording for identifying the chewing side. Body weight was tracked weekly to examine the effect of BoNT/A on general health. From each of these recordings, 15-20 consecutive chewing cycles from each chewing side were sampled and analyzed for chewing cycle length, muscle mean and integral activity, and durations. The preliminary results indicate that the recovery patterns of the 11-12 weeks after each BoNT/A injection differed significantly, and both the chewing frequency and muscle activity 11 weeks after the 3rd injection (week 35) were close to those of saline animals and the baseline recorded before injection. These findings provide new information about the consequences of multiple applications of BoNT/A on masticatory muscles, and may lead to the better understanding and use of BoNT/A in clinical dentistry.
- Presenter
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- Kelsey Marie (Kelsey) Haas, Senior, Biology (Molecular, Cellular & Developmental) Amgen Scholar, Mary Gates Scholar
- Mentors
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- Judit Villen, Genome Sciences
- Danielle Swaney, Genome Sciences
- Session
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- MGH 241
- Easel #172
- 12:45 PM to 2:15 PM
Protein phosphorylation is a common regulatory mechanism carried out by the cell, as adding a phosphate group to a particular protein can switch its activity on or off. Signaling pathways employ this control method to instigate series of phosphorylation events that elicit a particular cell response. Our research involves extracting and characterizing the phosphoproteome, or the cell’s entire set of expressed phosphorylated proteins, in both yeast and mammalian cell models. To generate lists of phosphoproteins present in these cell models, we use mass spectrometry, an analytic technique that produces characteristic spectra for individual phosphopeptides that are then matched to a library of known protein spectra through the use of computer algorithms. In our preliminary results, we have generated large-scale data sets identifying thousands of phosphorylated proteins present in each species and cell type. The goal of the first project, the yeast study, is to determine the degree of evolutionary conservation in phosphorylation events across 19 yeast species to learn about the basic principles of phosphoregulation. The conservation of phosphorylation can also give insight into phosphorylation events in other species evolutionarily related to yeast, such as humans. The second project, the mammalian cell study, examines the phosphoproteome of different breast cancer cell types in order to identify common phosphorylated proteins, from which we can deduce a molecular signature for breast cancer. This signature can be used in future studies to design a universal protein inhibitor drug as an alternative anti-cancer therapy. Additionally, by identifying the phosphoproteins exclusive to each cell type, we can uniquely characterize specific types of breast cancer. Knowledge of the proteins active in one type of breast cancer may facilitate development of inhibitor drugs as a form of personalized medicine.
- Presenter
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- Chase G (Chase) Halsen, Senior, Earth & Space Sciences
- Mentors
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- Elizabeth Nesbitt, Earth & Space Sciences
- Ruth Martin, Earth & Space Sciences
- Session
-
- Balcony
- Easel #108
- 12:45 PM to 2:15 PM
Foraminifera are a diverse and extensive group of marine shelled protists that are found all over the world, including Puget Sound. Because foraminifera are relatively abundant, short-lived and susceptible to environmental change, they have the potential to be inexpensive and effective environmental monitoring tools for local estuaries. Since Puget Sound exploits its water ways for industrial profit, foraminifera could prove to be useful tools for environmental monitoring. Thus it is surprising that, to date, no one has ever catalogued and observed foraminifera in the Sound to search for any changes in structure, abundance or diversity that could indicate a change in the environment. In fact Puget Sound is the only industrialized waterway that has not done this. The purpose of this project is to assemble an atlas of the foraminifera found in Puget Sound, from Bellingham Bay to south Sound. This atlas contains photographs, and in-depth descriptions of each foraminifera species. A catalogue such as this is a useful tool because it helps to better understand the foraminifera of Puget Sound and furthers the understanding of the organisms and their ecosystem. This atlas can also be used as a quick and easy reference to compare any changes discovered among foraminifera and their communities. Ultimately, the complete atlas will be submitted to Paleontologica Electronica for publication.
- Presenter
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- Anuradha Santosh (Radha) Helekar, Junior, Psychology
- Mentor
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
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- Commons West
- Easel #33
- 12:45 PM to 2:15 PM
Autism Spectrum Disorders (ASD) are characterized by atypical social development, decreased verbal and non-verbal communication, and repetitive behaviors. Retrospective studies of children with autism suggest an association between pregnant mothers’ use of certain medications and the occurrence of ASD diagnoses in their children. Other findings have also determined a relationship between an infant’s cognitive development and maternal mental health. In addition to maternal variables influencing development, infants may be at genetic risk based on sibling status: specifically, infants with siblings who have been diagnosed with ASD are at high-risk for also developing ASD. Using data from the Early Connections study – a longitudinal study of high-risk infant siblings compared to low-risk infants, we examined whether maternal variables resulted in added risk for poor child outcomes in the high-risk group. Information about family history of medical and psychiatric diagnoses, mother’s medication use during pregnancy, pregnancy complications, and other details pertaining to the mother’s delivery history were compiled for three groups: infants who develop autism (high risk, n=13, low risk, n=1); high risk infants who do not develop autism (n=32); and low risk infants who do not develop autism (n=42). Data analysis is ongoing. This study will examine the role of prenatal and postnatal effects in infant development in a high-risk sample. It is expected that mothers of high-risk infants will exhibit more medical and psychiatric conditions.The results of this study could aid in medical care for families who have a child with autism and are considering care options during a later pregnancy.
- Presenter
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- Ashton Stuart (Ashton) Hemphill, Senior, Bioengineering Mary Gates Scholar
- Mentors
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- Pierre Mourad, Neurological Surgery
- Suzie Pun, Bioengineering
- Session
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- Commons East
- Easel #66
- 12:45 PM to 2:15 PM
Traumatic brain injury (TBI) is injury to the brain caused by external trauma. Approximately 1.7 million cases of traumatic brain injury are reported every year in the US, and contributing to an estimated 30.5% of injury related deaths. TBI is currently treated by managing symptoms, present treatment methods are incapable of reversing the damage done by the initial trauma. Gene therapy is a promising method of treatment for TBI; by transfecting cells such as neural stem or progenitor cells (NSCs and NPCs respectively) in the brain with plasmids which induce differentiation and migration damage to neurons can be alleviated or even reversed. This projects aims to develop and optimize a protocol which utilizes non-viral transfection vectors in conjunction with ultrasound to efficaciously target and transfect neural progenitor cells (NPC), i.e. cells capable of differentiation into neurons. By transfecting NPCs with plasmids which cause differentiation and/ or migration NPCs can be induced to become new neurons and migrate to areas of neuronal injury caused by traumatic brain injury. In this manner some of the dead and dying neurons might be replaced and the initial trauma mitigated. This is a novel method of treatment both in its use of non-viral vectors capable of targeting NPCs in conjunction with ultrasound mediated increase in transfection efficiency and in its potential for reversing the initial damage seen in TBI; something that no current method of treatment is capable of.
- Presenter
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- Joshua Hewitt, Non-Matriculated, Molecular Biology-Post bacc, PREP, University of Washington
- Mentors
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- Leslie Itsara, Molecular & Cellular Biology
- Leo Pallanck, Genome Sciences
- Session
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- MGH 241
- Easel #166
- 12:45 PM to 2:15 PM
One of the most vital roles of mitochondria is to provide the cell with energy through oxidative phosphorylation (OXPHOS). Mutations within the mitochondrial DNA (mtDNA) can affect gene products that function in OXPHOS. While maternally inherited mtDNA mutations often affect the nervous system and musculature, and somatic mtDNA mutations are associated with aging and age related diseases, the cellular mechanisms that influence the frequency of mtDNA mutations are poorly understood. We are using the fruit fly Drosophila to address this matter because our recent work indicates that the mtDNA mutational patterns in flies share many features with vertebrates, including a similar somatic mtDNA mutation frequency, a prevalence of transition mutations, and an accumulation of mutations with age. A high prevalence of mtDNA mutations can lead to dysfunctional mitochondria, and previous work in Drosophila has shown that a mitochondrial quality control mechanism exists to degrade dysfunctional mitochondria. Although it is clear that this mitochondrial quality control mechanism can detect and degrade damaged mitochondria, whether it can influence the mtDNA mutation frequency by detecting and degrading mitochondria with a mtDNA mutation is unknown. To address this matter we will use a high-fidelity Duplex Sequencing approach to detect rare mtDNA variants. Genetic manipulations in mitochondrial quality control factors will be used to probe their effect on mtDNA mutation frequency. We predict that loss of these quality control factors will cause an increase in mtDNA mutations and that overexpression of these factors will cause a decrease in mtDNA mutations. The results from these studies will lead to improved understanding about factors that influence mtDNA mutation frequency and also diseases caused by mtDNA mutations.
- Presenter
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- Ryan Alan (Ryan) Hicks, Junior, Anthropology
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #8
- 12:45 PM to 2:15 PM
What cultural norms do the Rat City Rollergirls challenge and what are the implications of creating these new norms? Women and sports have by and large been at odds in America because of societal pressures and cultural norms that hyper-sexualize athletic women and undervalue their athletic achievements. Conversely, many women who challenge this are considered unwomanly and become unjustly labelled as a “beast” and often times their sexual identity becomes questioned. I will be exploring how women, specifically the all female roller derby league, the Rat City Rollergirls are challenging and creating new cultural norms by employing research methodologies such as, photo analysis, discourse analysis, ethnographies, and observations in order to answer these inquiries. It is important to study these cultural norms to elucidate a seemingly complicated and elusive societal bias towards women athletes and identify the root causes, what types of actions or behaviors continue the standard cultural norms, and how action can be taken to further challenge these long standing biases. To properly answer this inquiry I examined my own positionality regarding sports to uncover any hidden biases and then used this insight to remain open minded and unbiased while conducting further research. By analyzing the social media surrounding the Rat City Rollergirls I will be able to answer, in part, much of this inquiry. Using the Seattle Times’ online database I will deconstruct the hidden associations and meanings behind the pictures that I analyze. Furthermore, I will analyze the discourse used within these articles, as well as other social media sites, such as online forums, to see if my results are congruous with the dominant cultural norms regarding women in sport within America. The Rat City Rollergirls are challenging and changing these norms in new and exciting ways through the use of naming strategies, imagery, and events.
- Presenter
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- Danee Hidano, Senior, Bioen: Nanoscience & Molecular Engr Levinson Emerging Scholar, Mary Gates Scholar
- Mentors
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- Daniel Ratner, Bioengineering
- Eun-Ho Song, Bioengineering
- Session
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- Commons East
- Easel #46
- 12:45 PM to 2:15 PM
Active drug targeting involves a specific “lock and key” binding interaction, which enables drugs to be delivered exclusively to specific sites in the body thereby reducing the toxic side effects and improving the efficacy of the drug. However, the field of active-targeting lacks an efficient drug carrier. We are proposing to use a RAFT-based glycopolymer as a novel drug carrier. It is composed of three different types of monomers: 1) pyridal-disulfide methacrylate (PDSMA) for drug conjugation to the polymer through a disulfide bond, 2) hydroxyl propyl methacrylate (HPMA) to make the polymer biocompatible and soluble in the body, and 3) carbohydrate monomers that enable active-targeting through the specific carbohydrate-receptor interactions on outer cell membranes. Then the three monomers are polymerized together by reversible addition-fragmentation chain transfer (RAFT) polymerization. The resulting copolymers were characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The polymer size is around 8.5 kDa with low polydisperisty (<1.1). The polymer composition is 5% PDSMA, 75% HPMA, and 20% carbohydrate. The bioactivity of these polymers has been tested by surface plasmon resonance (SPR). In order to test the binding specificity of the mannose copolymer to ConA, I tested two different copolymers that contained different carbohydrate monomers. One polymer contains mannose, which specifically interacts with ConA. On the other hand, galactose, a stereoisomer of mannose, does not bind to ConA as expected. These results are promising because the mannose copolymer demonstrates good bioactivity, even though it contains a lower composition of mannose. These RAFT-based glycopolymers provide insight into the design of future active-targeting drug delivery systems.
- Presenter
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- Corina (Corrie) Hines, Non-Matriculated, Pre-Veterinary, North Seattle College
- Mentor
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- Elizabeth Goulet, Biology, North Seattle Community College
- Session
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- MGH 241
- Easel #145
- 12:45 PM to 2:15 PM
As human development continues to encroach on wild places, wetland bird species lose vital nesting habitats. To combat that loss, many cities nationwide create urban wetlands, in part to protect or replace lost habitat; it is unknown how effective this effort is. Previous Canadian studies identified four wetland bird species that do not generally nest in urban wetlands in Eastern Canada: American Coots (Fulica americana), Pied-billed Grebes (Podilymbus podiceps), American Bitterns (Botaurus lentiginosus), and Virginia Rails (Rallus limicola). This project will compare four urban wetlands with four rural wetlands in King and Snohomish Counties to see if the four species show any nesting preference between urban and rural wetlands. In addition, the project will investigate if those target species that nest in both urban and rural areas exhibit greater habituation to human presence in urban areas. I will visit each of the eight wetlands weekly during the morning or early evening and note the presence of courtship or nest-building activity and the number of individuals of each species exhibiting those behaviors. Using a laser distance device, I will measure the distance between the birds or their nest and the closest human access point to determine relative habituation. If urban wetlands birds are more habituated to humans, they will nest, on average, more closely to human access points than their counterparts in the rural wetlands. If urban wetlands are effective as nesting habitat, then mated pairs of the target species will utilize them, demonstrating that small created wetlands can serve as a buffer to habitat loss for wetland birds.
- Presenter
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- Keiji (KJ) Hiramoto, Junior, Extended Pre-Major
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #9
- 12:45 PM to 2:15 PM
The research question for my poster project will be, "Do media portrayals of the financial hardships NBA players endure impact youth who aspire to play at that level?" The thesis to go with the above research question will be that the media’s tendency to glorify materialism plays a direct role in not only influencing lavish spending among current NBA players, but also contributing to the prevalence in the cycle of former NBA players experiencing financial stress by sending a similar message to future NBA players. For the hypothesis of my research, I referred to the financial case study of Allen Iverson to make the prediction that expenses coming from taxes, supporting family members, child support, divorce, and lavish spending habits are the common factors that apply to the reported 60% of NBA players that struggle financially within five years after their professional basketball career is over. As means of conducting the research, the arguments presented by Todd Kendall’s Journal of Sports Economics were used to explain why it is prevalent for superstar athletes to struggle financially during or after their professional athletic careers. To list some of the common factors that often leads to NBA players filing for bankruptcy, the episode “Broke” from ESPN’s 30 for 30 series were also used as references. My third research method used were the discourse analysis from interviews of elite basketball players in both high school and college levels as means of determining whether or not these amateur athletes have been affected by the media's portrayals of professional basketball players. The findings from my research brought implications to the idea that the media plays a role in contributing to the apparent cycle of NBA players encountering financial struggles by glorifying materialism and affluence to these players from a young age.
- Presenter
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- Gar-Yun Christina (Gar-Yun) Ho, Senior, Landscape Architecture, Environmental Science & Resource Management
- Mentor
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- Soo-Hyung Kim, Environmental & Forest Sciences, UW, College of Engineering
- Session
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- MGH 241
- Easel #153
- 12:45 PM to 2:15 PM
Extensive green roofs provide environmental, economic, and aesthetic benefits. Some benefits include: improvement of storm water management, conservation of energy, mitigation of urban heat island effects, reduction of noise and air pollution, provision and enhancement of habitat for urban biodiversity and sequestration of carbon. However, although green roofs may reduce the volume and velocity of storm water runoff, studies have shown that the quality of green roof runoff is decreased from higher levels of water-soluble nitrates and phosphorus being leached from fertilizers present in green roof substrate. Biochar, a by-product of the pyrolysis of organic materials thermally decomposed to produce energy, has proven to provide multiple environmental benefits including the reduction of pollutants from fertilizers, increased water-holding capacity, and potential carbon sink capabilities. This project will evaluate the impact biochar has on the quality of runoff leached from green roof soils, as well as water-retention abilities. Two different types of 7% (v/v) biochar, added to a green roof soil mix currently used in a permanent installation at the University of Washington, will be tested. 5 cm deep green roof trays with and without biochar will be planted with common green roof species: Allium cernuum (nodding onion), Festuca glauca (blue fescue), and Anaphalis margaritacea (western pearly everlasting), and unplanted trays with and without biochar will also be tested as controls. Controlled “rainfall” events will be conducted on the green roof trays, and runoff will be collected and analyzed for nutrient content and electrical conductivity. An appropriate substrate composition is essential to reap the full environmental benefits that extensive green roofs could provide. Amending green roof soils with biochar may be the key to improving storm water runoff quality and potentially mitigating a future source of water pollution.
- Presenter
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- Tanner Justin (Tanner) Hoecherl, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Kannan Krishnan, Materials Science & Engineering
- Byung Seok Kwon, Materials Science & Engineering
- Session
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- MGH 241
- Easel #136
- 12:45 PM to 2:15 PM
Nanoimprint lithography (NIL) has become a widely used technique in fabricating nanoparticles using a top-down approach with several advantages over bottom-up chemical methods, including being able to precisely control particle shape, size, structure, and composition. Using NIL, synthetic antiferromagnetic (SAF) nanoparticles can be fabricated using multilayer deposition techniques, imprinting, liftoff, and particle release into water with limited defects. The particles can also be coated with a functional polymer so that they can be used in a number of drug delivery systems. However, common NIL techniques often make it difficult to add functional coatings to the particles after the particles are released in water. Deposition methods for different layers, as well as using silicon molds that introduce defects and irregularity in particle size are other pitfalls that can be corrected using a new approach. The nanoparticles (~300 nm diameter) were homogeneously patterned using a mold to etch disk-shaped nanoparticles on a silicon substrate with layers of titanium and magnetite deposited on its surface via magnetron sputtering to contribute to the antiferromagnetic properties of the particles. The fabrication process is extensive and utilizes many clean room processes, including nanoimprinting, dry etching, undercutting, multilayer deposition, liftoff, and polymer coating, though polymerization was not explored in this study. Following, release techniques were used to produce a monodisperse and homogeneously-sized sample of high moment, multilayer particles in water with high saturation magnetization and low toxicity. Final results to determine the effectiveness of the particles were determined by studying the magnetic properties of the nanoparticle solution sample in the presence of an external magnetic field. With antiferromagnetic and useful imaging properties, functional biomagnetics could become a highly useful material system. Future work in this field includes biofunctionalizing the particles to modify in-solution behavior and implementing them into various biomedical systems, depending on how small the particles can be made using NIL.
- Presenter
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- Kunichika William (Kuni) Hongo, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Kannan Krishnan, Materials Science & Engineering
- Amit Khandhar, Materials Science & Engineering
- Session
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- MGH 241
- Easel #137
- 12:45 PM to 2:15 PM
Iron-oxide magnetic nanoparticles (MNPs) with tuned magnetic properties can enable novel diagnostic and therapeutic technologies such as magnetic particle imaging and hyperthermia. In order to optimize the magnetic properties of MNPs, organic synthesis methods are required. However, these organic synthesis methods render the nanoparticles hydrophobic and unusable for biomedical applications. To make MNPs functional in biomedical applications whilst retaining their magnetic functionality, they must be transferred to the aqueous phase using a biocompatible polymer. In this work, MNPs will be coated using a biocompatible PEG-ylated amphiphilic polymer: poly (maleic anhydride-alt-1-octadecene) or PMAO-PEG. To ensure the PMAO-PEG is a well suited polymer coating for MNPs, various molecular weights and molar ratios of PMAO-PEG are synthesized and characterized to study the effects of PEG surface density and molecular weight on MNPs. By altering the density of the polymer used to coat and phase transfer MNPs, effects such as the solubility, circulating life, colloidal stability, dosage frequency, and proteolytic degradation rates of MNPs in the biomedical applications are studied using data obtained from Gel Permeation Chromatography (GPC) and Fourier Transform Infrared Spectroscopy (FTIR). Molecular weight distributions of the various polymers are obtained from the GPC to evaluate the conjugation success after PEG-ylation. In addition, FTIR was used to identify known and unknown materials in the samples, determine the quality and consistency of samples, and to determine the amount of components in samples.
- Presenter
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- Jeremy Benson (Jeremy) Housekeeper, Senior, Chemistry Mary Gates Scholar
- Mentors
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- Christine Luscombe, Materials Science & Engineering
- Ken Okamoto, Materials Science & Engineering
- Session
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- Balcony
- Easel #91
- 12:45 PM to 2:15 PM
Until recently, little research has been done on C-S bond formation in transition-metal catalyzed transformations compared to other carbon-heteroatom bonds such as C-N, C-O, and C-P. As sulfur-based coupling partners (thiol and disulfide for example) tend to poison transition-metal catalysts, development of C-S bond formation has been slow. However, a recent nickel-catalyzed system shed new light on this difficult transformation. In this context, C-H functionalization is a sustainable and straightforward approach to sulfur-containing heteroaromatic production. C-H activation is a process whereby a carbon-hydrogen bond is cleaved, thereby allowing the exposed carbon atom to form new bonds. Thus, in order to expand the above research of C-S bond formation toward development of short synthesis for fused thiophene systems, focus was placed on a palladium catalyzed cascade-type reaction system. C-H activation reactions can and have been manipulated to work in a cascade-type fashion. By combining cascade-type methodology with the reduced environmental impact of C-H activation, these fused thiophenes can be synthesized cleanly and efficiently. The test substrates in this work are O,O-diethyl S-phenyl phosphorothioate and 4,4,5,5-tetramethyl-2-(thiophen-2-yl)-1,3,2-dioxaborolane. Both substrates were chosen because they contain sulfur, thereby aiding the C-H activation process. By effecting a C-H activation with a palladium catalyst at one of the ortho carbons of the phenyl ring with the boronic ester of the thiophene, the first C-C bond will be formed. In the time immediately after this first transformation, the now-changed palladium complex is able to insert into the S-P bond of the phenyl-based compound. This step sets up the second reaction, whereby the phosphorothioate directing group is cleaved along the S-P bond and the resulting thiol is coupled to a carbon atom to close the ring. This molecule is known as benzo[b]thieno[2,3-d]thiophene.
- Presenter
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- Stephen Tzung-Cheng (Stephen) Hsieh, Senior, Chemistry NASA Space Grant Scholar
- Mentors
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- David Ginger, Chemistry
- Adam Colbert, Chemistry
- Session
-
- Balcony
- Easel #121
- 12:45 PM to 2:15 PM
Hybrid organic/inorganic composites of conjugated polymers with quantum dots are of interest due to their potential for low-cost, solution processable solar cells and photodetectors. We use photoinduced absorption (PIA) spectroscopy to study charge generation in hybrid bulk heterojunction blends of the conjugated polymers with PbS quantum dots. We have previously shown that selective excitation of the quantum dots leads to formation of positively charged polarons on the conjugated polymer. By computing the relative yields of long-lived holes following photoexcitation of both the polymer and quantum dot phases, we estimate that more long-lived polarons are produced per absorbed photon by the polymer phase than the quantum dot phase. In this study, we aim to determine whether the formation of long-lived charge carriers due to quantum dot photoexciation is wavelength-dependent by investigating the polaron yield resulting from selective PbS excitation at varying energies in the near infrared. These results will give insight into the process of hole transfer from photoexcited quantum dots to the organic host polymer.
- Presenter
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- Philip Peter (Philip) Huang, Senior, Biochemistry
- Mentor
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- Jay Parrish, Biology
- Session
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- Commons East
- Easel #84
- 12:45 PM to 2:15 PM
The basic functional unit of the nervous system is the neuron, which contains two highly specialized compartments, the axon and dendrite. Dendrites received synaptic/sensory inputs, and the dendrite arborization pattern has a profound influence on the type and number of inputs a dendrite can receive. We are studying dendrite patterning in the Drosophila peripheral nervous system (PNS), with a particular focus on the role that non-neuronal signals play in shaping dendrite development. In the Drosophila PNS, sensory neurons grow on top of a monolayer of epithelial cells, which provide instructive cues to shape dendrite patterning. To date, there are plenty of tools available to genetically label and manipulate neurons, but few tools are available for genetic manipulation of epithelial cells. My goal is to design a reporter construct that will specifically label and facilitate targeted expression of transgenes in epithelial cells. To this end, I am assembling a modular plasmid construct which contains a minimal promoter, an enhancer sequence which we have found to be sufficient to direct epithelial expression, and the coding sequence of green fluorescent protein or other genes of interest. After assembling the construct, I will use germline transformation to generate transgenic flies and test the efficacy of the construct. If successful, this will represent the first epithelia-specific transcriptional reporter, and will provide a template for assembly of additional tools for studying dendrite-epithelia interactions.
- Presenters
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- Mei Huang, Senior, Public Health-Global Health
- Anne Elisabeth (Annie) Young, Senior, Neuroscience Mary Gates Scholar
- Bryony Lynch, Senior, Biology (General)
- Mentors
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- Aaron Miller, Genome Sciences
- Maitreya Dunham, Genome Sciences
- Session
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- MGH 241
- Easel #171
- 12:45 PM to 2:15 PM
Chemostats are a continuous culture system in which cells are grown in a tightly controlled, chemically constant environment where culture density is constrained by limiting specific nutrients. Unlike batch cultures, the selective pressure imposed in a chemostat is constant. This has made them a desirable tool for evolution and competition experiments. Traditionally, chemostat experiments with S. cerevisiae have been constrained due to the limited number of cultures that can be run at once. In order to solve this problem our team is working with a new culturing system that allows 64 chemostats to be run simultaneously. In our experiment we evolved 96 biological replicates of haploid MATa yeast cells under either constant sulfur, phosphate, or glucose limiting environments for 300 generations. We are now using a variety of techniques including array-comparative genomic hybridization and whole genome sequencing of evolved populations to characterize mutations that have been selected for during the course of these evolution experiments. These techniques have revealed that amplification of genes that code for nutrient transporters are a common mutation that occur in the evolved populations over the course of the experiments. Therefore, we will also be experimenting with strains that have the most common amplified genes knocked-out in the hopes of identifying alternative pathways for nutrient-limited fitness increases. Changes in the genome can be correlated to changes in relative fitness, which we assayed through competition with a green fluorescent protein (GFP) expressing ancestral strain every 50 generations. Ultimately it is our hope that higher replicate number will better reveal the spectrum of genes important for adaptive growth in specific nutrient-limited environments.
- Presenter
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- Maile E Hunter, Junior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #1
- 12:45 PM to 2:15 PM
Accessibility to sports is not equitable to all groups of people. Individuals living in low economic and homeless communities do not have the same opportunities to sports, as those of a higher socioeconomic standing. This disparity can reinforce negative stereotypes because children especially will follow the expectations set for them. Having inequitable accessibility to sports is a concern of physical health, for sports promotes exercise. What are the economic barriers in accessibility to sports in the lower economic population? The methods I will use to conduct my research are interviewing, discourse analysis, and social mapping. I will interview members of these communities to learn about their accessibility to sports, as well as attitudes revolving around sports. I will also analyze the overall discourse around homeless and low socioeconomic populations. The method of social mapping will help to illustrate the physical accessibility to sports for these groups of people. The anticipated results will demonstrate how economic barriers such as, the cost of housing, are too great of an impediment to overcome. The populations of higher economic standings are often not aware of the extensive economic barriers. It is important to raise awareness about the inequality to accessibility, for everyone should have equitable opportunity to basic recreation. By creating awareness of sports inaccessbility, I hope to ultimately bring about change on a governmental level. This is a health disparity that demands attention.
- Presenters
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- Kimberly Zien (Kimberly) Huynh, Junior, Pre-Health Sciences
- Tong Meng, Senior, Psychology, Economics
- Mentor
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
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- Commons West
- Easel #32
- 12:45 PM to 2:15 PM
Autism is a developmental disability characterized by social deficits, communication deficits, and repetitive behaviors. Previous research has shown that having an older sibling with autism is a significant risk marker for a younger infant sibling developing ASD. The Early Connections study investigated the developmental trajectory of infants, looking for early markers that may predict whether or not ASD will be developed later on in toddlerhood. The two subject groups were identified as follows: high-risk (infants with an older sibling with ASD) and low-risk (infants that do not have any family history with ASD). Both groups were tracked longitudinally from 6 to 24 months at 6-month intervals. The Communication and Symbolic Behavior Scales Developmental Profile (CSBS DP), an assessment tool for early communication in infants and toddlers, was administered to both groups at 12 and 18 months. Each infant was videotaped during the CSBS DP administration and those videos were coded offline by trained undergraduate coders. Coding is still in progress. Using the CSBS DP, previous studies have shown that delayed word, sound, and language development are consistent markers for ASD. Therefore, we expect infants from the high-risk group to have lower CSBS DP scores in word and sound acquisition domains when compared to the low risk-group. A better understanding of early deficits in the core elements of language development will provide researchers with clearer insight on early identifiable signs of ASD. Targeted intervention in language acquisition may help children at high risk for ASD overcome potential communication deficits earlier on in development, thereby improving future prognosis.
- Presenter
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- Ranee James, Junior, Physics: Biophysics
- Mentor
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- Jay Parrish, Biology
- Session
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- Commons East
- Easel #83
- 12:45 PM to 2:15 PM
Dendrites are branched extensions of the cell body of a neuron that act to receive and process synaptic or sensory inputs. The elaborate branching pattern of the dendrite is a hallmark of neural type, and has a considerable impact in determining what signals a neuron receives, and how these signals are integrated. Alterations of dendrite morphology can lead to abnormalities in neuron function--dendritic defects are associated with neurological disorders such as Ret syndrome, Fragile-X syndrome, and Down syndrome, and in many cases the dendrite pathologies are progressive. Therefore we set out to identify mutations that result in progressive defects in dendrite growth and stability with the hope that the genes affected by these mutations and the processes in which they regulate will provide new insight into human disease. A series of complementation tests using chromosomal deficiencies, as well as meiotic mapping have been used to map one such mutant (cc215) to a small chromosomal interval. In addition, we have performed a non-complementation screen to determine other alleles that affect the same gene mutated in cc215. Complementation tests and sequence analysis are currently being performed to classify the gene affected by this allelic series, which will allow us to investigate the underlying cause(s) of the dendrite defects in the mutants.
- Presenters
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- Tiffany Channelle (Tiffany) Jansen, Freshman, Pre-Sciences
- Andrew Paul Hillman, Sophomore, Pre-Sciences
- Mentors
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- Suzanne Hawley, Astronomy
- James Davenport, Astronomy
- Session
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- Balcony
- Easel #97
- 12:45 PM to 2:15 PM
M dwarf stars are classified by their small radii and relatively cool surface temperatures. Their internal structures are known to be almost entirely convective, and this extreme convection causes a tangling of the stars' magnetic field lines. Upon realignment of the magnetic field lines, an incredible amount of energy is released from the star in what is called a flare. This research project is an ongoing observation of the flare activity on the M dwarf stars GJ1243 and GJ1245. Two months of flare activity was observed using the flux measurements made by NASA's Kepler telescope. The frequency, duration and types of flares were recorded and analyzed with the aid of the computer program "Flares by Eye." It has been observed that most flares have short rise times and long decay times, the intensities of which seem to follow a power law. Continued research on this topic will help us learn more about the physics behind the ignition of these stellar explosions, how the flares decay, and how the stars become less active as they age.
- Presenter
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- Zachary Ryan (Zack) Jarin, Senior, Chemical Engr: Nanosci & Molecular Engr
- Mentor
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- Jim Pfaendtner, Chemical Engineering
- Session
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- Balcony
- Easel #118
- 12:45 PM to 2:15 PM
Currently, the United States faces an impending energy crisis. To ensure energy security, conversion of biomass to small molecules for use in fuels or chemical processes must become more energy efficient. However, a major hurdle to raising productivity is the robust structure of biomass and subsequent resistance to breakdown. In the past ten years, experiments have shown “ionic liquids,” a special group of solvents, dissolve biomass. Unfortunately, these experiments are not guided by molecular scale design principles hindering this promising research. This project focuses on providing the fundamental knowledge to guide and explain the phenomenon by using molecular dynamics (MD) to study the interaction of cellulose and other parts of biomass as a function of solvent environment. This new perspective requires simulated MD in combination with an enhanced sampling method. Enhanced sampling, in this case umbrella sampling, involves applying artificial forces on atoms to cause rare events that would not normally occur on the time scale of molecular scale simulations. Examples of rare events that are challenging to directly observe in MD simulation include chemical reactions, protein folding and unfolding and binding and unbinding of polymers. This work focuses on binding and unbinding events of biomass polymers. To cause the binding and unbinding events, umbrella sampling uses a force similar to a spring to hold a variable like dihedral angles and number of hydrogen bonds constant. Umbrella sampling is a versatile technique and is used on a wide variety of variables but this work uses it to vary the position of the dimer with respect to the cellulose surface. By varying position, the interaction energy is calculated. The interaction energy will give a deeper insight into the mechanism of dissolving biomass while providing a profounder understanding of the fairly new materials, ionic liquids.
- Presenter
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- Christina Jarvis, Junior, Biology (General)
- Mentor
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- Joseph Sisneros, Psychology, UNIVERSITY OF WASHINGTON
- Session
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- Commons West
- Easel #17
- 12:45 PM to 2:15 PM
The swell shark, Cephaloscyllium ventriosum, is one of the most popular sharks in public aquaria on the west coast of the United States, but very little is known about the early growth and development of this species. Swell sharks, members of the catshark family Scyliorhinidae, are small oviparous sharks that lay semi-translucent egg cases which they attach to rocks and seaweed during egg laying. Limited data on post-hatch growth exists for this shark, but there is essentially no data available on the early growth and gestation time of this shark within the egg case. The goal of this study was to determine the gestation period and early growth of the Swell shark. The gestation time of 10 egg cases and the post-hatch growth rates of 39 swell sharks were recorded over a 23-month period. Juvenile swell sharks were reared from egg cases deposited in laboratory aquaria during July 1990 by eight female swell sharks previously caught off Santa Barbara Island, California. Mean gestation time for the eggs (n = 10) maintained at 13.5-17.5° C with a constant photoperiod (12 hrs light, 12 hrs dark) was 264.4 + 18.106 SD days. Newly hatched sharks had a mean total length (TL) of 15.3 + 0.7 cm SD (n= 42) and had a mean weight of 15.0 + 1.4 g SD (n= 27). The average percent growth of sharks approximately one year old (n=21) was 38.74 + 7.66 % SD. The gestation time of C. ventriosum is significantly longer than that of a similar catshark, Hemiscyllium osellatum, which has a gestation period of just 140.3 ± 4.6 days. However, TL at hatching was very similar to this species and the average neonate length of H. osellatum was 16.5 ± 0.5cm and average weight was 19.9 ± 2.1 g.
- Presenter
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- Jan Andrew (Jan) Jimenez, Freshman, Pre-Sciences
- Mentor
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- Chet Moritz, Neurobiology & Behavior, Physiology & Biophysics, Rehabilitation Medicine
- Session
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- Commons East
- Easel #61
- 12:45 PM to 2:15 PM
Research in our lab has demonstrated that stimulation of the spinal cord may enhance rehabilitation and restoration of forelimb function after spinal cord injury. Building on previous experiments, the goal of this project is to see how the combination of Chondroitinase (a treatment of enzymes) and spinal stimulation could promote the recovery of forelimb function in rats with chronic spinal cord injury. We trained animals on a skilled forelimb reaching task and determined their dominant hand. Once trained to proficiency, animals received a contusion injury to the lateral aspect of the 4th and 5th cervical segments resulting in paresis of their dominant forelimb. Animals were then randomly assigned to groups receiving stimulation, Chase treatment, or the combination of the two treatments. We are conducting a battery of forelimb functional tests, including skilled forelimb reaching, each week for the duration of the study in order to record their progress and observe their improvement using the injured forelimb. It is the anticipated result that the addition of Chonroitinase during rehabilitation will result in an increase of the formation of synapses in circuits bypassing the lesion, which may be investigated using neuroanatomical tracing techniques. If successful, our results can be utilized in human medicine to improve the healing of a spinal cord-related injury and promote rehabilitation.
- Presenter
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- Alysa Marie Joaquin, Fifth Year, Chemical Engr: Nanosci & Molecular Engr Mary Gates Scholar
- Mentor
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- Lilo Pozzo, Chemical Engineering
- Session
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- Balcony
- Easel #112
- 12:45 PM to 2:15 PM
The behavior of polymer/protein mixtures has been widely studied within the framework of depletion forces, a colloidal phenomenon driving the attraction of like-particles due to osmotic pressure. However, the behavior of dilute polymer/protein mixtures is still not fully understood. Ordered protein structures, such as crystals and colloidal clusters, could be achieved by tuning excluded volume interactions through the modification of polymer conformation. The temperature-dependent morphology of block copolymers allows us to fine-tune these depletion interactions. To assess phase behavior in a model system, aqueous mixtures of protein (bovine serum albumin) and block copolymer (PEOx-PPOy-PEOx) have been created. Electrostatic interactions between proteins were screened by adding salt to the mixtures. The dependence of phase behavior on these parameters was determined using UV-Vis spectroscopy to measure turbidity. The morphology and size of protein structures was also evaluated using optical microscopy and dynamic light scattering. Mixtures with higher polymer concentrations displayed an increased propensity to develop turbidity at low temperatures. This effect was mitigated upon reaching the polymer micellization temperature, whereupon the decreased osmotic pressure reversed protein aggregation, resulting in a clear solution. Defining the conditions required for the formation of ordered protein aggregates in polymer media has valuable implications for biology and medicine. This work represents a step towards determination of the optimum conditions for creating protein crystals suitable for structural proteomics and colloidal clusters for drug-delivery.
- Presenter
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- Annika Alisa (Annika) Juhlin, Senior, Bioen: Nanoscience & Molecular Engr, Swedish Initiative for Maximizing Student Development Scholar
- Mentors
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- Ruying Chen, Bioengineering
- James Bryers, Bioengineering
- Session
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- Commons East
- Easel #44
- 12:45 PM to 2:15 PM
Bone tissue healing is problematic for more than a fifth of fractures, bone defects, massive bone loss, and osteoporosis and requires regeneration or implantation of bone. The introduction of a therapeutic bone strategy in the body elicits the foreign body immune response which is characterized by the inflammatory cell recruitment and subsequent encapsulation of the foreign material by fibrotic tissue. The formation of the fibrotic tissue is generated by a process in which macrophages adhere to the foreign material and fuse to generate multi-nucleated cells called foreign body giant cells (FBGCs). FBGCs effectively separate the foreign material from surrounding tissue resulting in sustained inflammation and reduced efficiency. This response, known specifically as the chronic inflammatory response, represents a very challenging complication for biomaterial fabrication in tissue engineering applications. Very recently, preliminary evidence has indicated that an optimal pore size exists in porous scaffolds that upon implantation result in the regeneration of a variety of tissues. Simultaneously incident findings in vivo have indicated that differentiated macrophage may have greater plasticity than previously accredited, and may transdifferentiate into various cell types. These advances may aid clinical treatments for bone repair by facilitating bone growth and avoiding stem-cell therapy controversies. The aim of the project was to design a porous scaffold to promote efficient bone tissue regeneration by enabling macrophage transdifferentiation. The proposed biomaterial synthesizes new information on optimal scaffold pore size and macrophage plasticity in conjunction with a well-studied osteoinductive cue, to both control the human body immune response and facilitate bone growth. The approach thus far has entailed an in vitro analysis of macrophage morphology and structural fabrication of the biomaterial.
- Presenters
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- Katharine Mary (Katie) Jung, Junior, Accounting
- Colin Chang, Senior, Business Administration (Entrepreneurship)
- Mentors
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- Kai Chi Yam, Business Administration
- Scott Reynolds, Business Administration
- Session
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- Commons West
- Easel #28
- 12:45 PM to 2:15 PM
In today’s world of globalization and expanding corporations, it is crucial that leaders act ethically to avoid the scandals, fraud, and financial collapses whose vibrations resonate internationally. Our research is guided by a desire to discover more successful strategies to teach ethics to business professionals and students. Unethical behavior spans an extensive range, all of which is financially costly for a company. Drawing from Ironic Thought Processing Theory, we hypothesize people will commit counterintentional errors when under a mental load, such as stress, fear, and distraction. In application to ethics, we hypothesize that participants directed not to think about ethics will consequently engage in less unethical behavior. Our hypothesis was tested with a sample of undergraduate business students, who were randomly assigned to one of three conditions. In the first two conditions, participants read passages about ethical principles, but one was instructed to reflect upon the ethics they read, whereas the other group was instructed not to consider ethical principles they read. Our third condition served as a control group, who read a similar length, yet irrelevant news article. Participants then attempted to complete 10 unsolvable math problems, requiring them to add impossible sets of numbers to 15, and report if they could successfully solve problems for extra cash payment. Results show that students who read about ethics, but are instructed not to think about it, engage in less unethical behavior when compared to the other conditions. Our study has broad implications. First, it is an application of the Ironic Thought Processing Theory in a new domain, widening its theoretical application. Second, our research will provide preliminary evidence to aid administrators to better structure business ethics curriculum.
- Presenter
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- Veronica Youn Kang, Junior, Biology (General)
- Mentors
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Esha Massand, Psychology
- Anna Kresse, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
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- Commons West
- Easel #31
- 12:45 PM to 2:15 PM
Autism is a disorder characterized by deficits in social and communication skills and repetitive behaviors. Fifty-two percent of the children with autism are treated with medication for some of the common co-morbid behaviors – e.g., anxiety, aggression, and hyperactivity. However, only 49-69% of these children respond positively to the medication, and about 18-26% of these children experience side effects such as insomnia, sedation, and increased appetite. An extensive series of trial-and-error might be needed for a patient, which could be time-consuming and stressful for both the patient and parents. A reliable method is needed to predict the effectiveness of the pharmacological treatment. This study used electroencephalography (EEG) to detect early changes in the brain that we cannot yet observe in behavior. Children who are diagnosed with autism and starting a medication (e.g. stimulant, antidepressant, or atypical antipsychotics) participated in this study. EEG was recorded while the subjects participated in a social processing task, a resting task, and the Go-NoGo inhibition task. The participant’s caregiver completed three questionnaires: Child and Adolescent Symptom Inventory, Aberrant Behavior Checklist, and Social Communication Questionnaire. This project analyzed the subject’s change in EEG and behavioral data over three different time points (T1= before, T2= one week after, T3= one month after the start of medication). Multiple aspects of each individual’s EEG signal were examined by comparing the difference from T1-T2 and T1-T3 against the null hypotheses of no change (or comparing change to 0). The goal of this project is to search changes in the EEG signal that is related to positive (or negative) behavioral changes in this population. This study will provide an important first step for understanding changes in the brain in response to medications, which may provide useful information to professionals during the process of choosing the most effective medication for children with autism.
- Presenter
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- Rylan John Kautz, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Christine Luscombe, Materials Science & Engineering
- Pinyi Yang, Materials Science & Engineering
- Session
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- Balcony
- Easel #92
- 12:45 PM to 2:15 PM
Organic Photovoltaics (OPVs) provide a potentially cheap and clean option to harvest energy from the largest source of energy available - the sun - however they are still fairly inefficient when compared to inorganic photovoltaics. Attaching fluorine to the polymer backbone has been shown as an effective way to increase the open circuit voltage (Voc) and power conversion efficiency of the devices by lowering the highest occupied molecular orbital of the polymer. However, the impacts of fluorine attachments on the other properties of active layer, like morphology under different processing conditions and electrical properties, have not been fully studied. Knowing this information will help the future designs and processing of donor-acceptor polymers for OPV application. In this project, three structurally identical polymers, with zero, one, and two fluorine attachments (named P0F, P1F, and P2F) were studied. The morphological impact of fluorine attachments are studied by varying the ratio of PCBM (a widely used and promising acceptor) and these three polymers as well as the solvents used when processing through atomic for microscope (AFM). Hole features were found on the surface of the thin film. The density of and depth of the holes were found to correlate to the number of fluorine attachments and processing condition respectively. Future works are being done to investigate the reasoning behind the device efficiency with the attachment of fluorine and differentiating whether this is due to these physical morphologies or bandgap manipulation being the primary contributor to a higher efficiency. The influence of fluorine on the dielectric constant of the thin film and operation of OPVs will also be studied.
- Presenter
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- Gillian Elizabeth Kenagy, Senior, Environmental Studies
- Mentor
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- James Lutz, Environmental & Forest Sciences
- Session
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- MGH 241
- Easel #156
- 12:45 PM to 2:15 PM
All plants contribute to the productivity and biomass of an ecosystem. With generalized formulas we have gained an understanding of these fundamental processes, however, to understand the precise contribution of a particular plant species more accurate and specific equations are required. Through the dissection and fine-scale measurements of individual plants, allometric equations relating detailed plant structure to easily measurable quantities (i.e., stem diameter) can be developed. Because of their relative small stature and relatively small contribution to total ecosystem biomass, little is known about the exact biomass and productivity of shrubs. Yet, diverse angiosperm shrubs in western forests can have a disproportionately large impact on the ecosystem in terms of providing a food source for wildlife and fuel for low-intensity fires. Field measurements and samples were collected from 41 individual plants of Cornus sericea L. [Cornaceae] (red osier dogwood) in Yosemite National Park, California, USA. In the lab I processed the field data and calculated a number of allometric equations, including cambial surface area, wood mass, bark mass, and foliage mass in relation to basal diameter and diameter at breast height. This dataset will generate a foundation for future research helping scientists more accurately determine carbon stocks, carbon sequestration rates, fuel loads, and other changing trends. The collection of more comprehensive and scientifically accurate data will also help improve land management policies in an era of projected climate change.
- Presenter
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- Adiba Khan, Junior, Biochemistry, Communication (Journalism) Mary Gates Scholar
- Mentor
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- Heather Mefford, Pediatrics
- Session
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- Commons East
- Easel #52
- 12:45 PM to 2:15 PM
Those who have studied genetics have a keen understanding of the fact that incredibly small changes can have tremendous, and often tragic, consequences. In patients with Fragile X Syndrome (FXS), a repeating sequence of genetic information (CGG) in an X chromosomal region is repeated more often than in the general population. This results in a spectrum of conditions including intellectual disability, anxiety, and physical features that deviate from the norm. About one fifth of people who have FXS also have seizures; the underlying cause of seizures in this fraction of FXS individuals is unknown. We hypothesize that FXS individuals who have seizures will have specific genetic variants –duplications and deletions of genetic information –that are not seen in FXS individuals without seizures. The experimental group is composed of DNA samples of FXS patients with seizures, while the control group will be composed of DNA samples of FXS patients without seizures. In order to find genetic variants, I utilize a genomic technique called array-comparative genomic hybridization (array-CGH). In array-CGH, DNA samples are tagged with fluorescent dyes to contrast patient DNA (tagged with pink dye) from control DNA (tagged with blue dye). The ultimate product of this technique is a quantitative representation of any differences between patient and control DNA, which can be processed and analyzed by computer software. By comparing the genomes of these patients, we will determine if there are common genetic variants across the experimental group that are distinct from the control group. If such variants are found, the next step is to associate specific genes with the subset. Establishing an association between a gene and the FXS and seizure phenotype is essential because it deepens our understanding of the condition and provides a foundation for future therapeutic treatments.
- Presenter
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- Tae Yen (Amy) Kim, Senior, Statistics, Economics
- Mentor
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- Peter Guttorp, Quantitative Ecology & Resource Management, Statistics, Urban Design & Planning
- Session
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- MGH 241
- Easel #149
- 12:45 PM to 2:15 PM
People have often heard statements like "2010 is the hottest year on record in the world." However, this ranking in order of average global temperature is uncertain, because the global temperature is not a direct measurement but a statistical combination of data, which by itself has uncertainty. We have developed new methods to rank each year taking into account the standard error of a real mean temperature. The methods give us distributions of the rank of each year's temperature, and allows us to compute the probability that a given year is the hottest year on record. We can arrange the years in order of these probabilities. The results are consistent with regular ranking of continental US annual mean temperature, but allows us to express the uncertainty of the ranks. We can also estimate, for example, the probability that 12 of the last 15 years have been among the hottest ever, as President Obama said in his State of the Union address in February.
- Presenter
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- Joon Kyung (Joon) Kim, Senior, Neuroscience, Psychology Mary Gates Scholar
- Mentor
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- Sean Murphy, Neurosurgery
- Session
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- Commons West
- Easel #20
- 12:45 PM to 2:15 PM
Stroke is one of the leading causes of death in the United States; however, due to the apoptotic death of neuronal cells from lack of oxygenated blood, prognosis and recovery is not always favorable even if the event is survived. Our laboratory focuses on finding therapeutic agents that show neuroprotective qualities in cerebral ischemic events. The compounds we have focused on in this study are progesterone and its metabolite allopregnanolone. Previous studies have shown that both compounds have neuroprotective qualities in vitro and that progesterone administration in vivo suppresses inflammatory response and subsequent edema. Our hypothesis is that both progesterone and allopregnanolone would show neuroprotective, as well as neurogenic, qualities in vivo. This is tested through a mouse stroke model using progesterone receptor knockout mice and wild type mice, both being subjected to a middle cerebral artery occlusion. Groups are treated with different compounds or control. The brains are then perfused after 11 or 28 days, fixed, and sliced to be put through immunohistochemistry, where cells are identified by certain neurogenic markers (bromodeoxyuridine incorporation and doublecortin labeling). Slides are finally analyzed through confocal microscopy to look for these markers in certain areas such as the hippocampus, striatum, and lateral cortex. Finally, positively labeled cells are counted in both the ipsilateral (stroked) and contralateral hemispheres. Data are currently being analyzed for 11 day post-ischemic mice. We anticipate an increase in the number of bromodeoxyuridine and doublecortin labeled cells in mice subjected to progesterone and allopregnanolone, and we also expect this to be more dramatic in the ipsilateral side due to new cell migration to the injury site. Hopefully, these results will allow for a greater push in implementing progesterone and allopregnanolone in clinical use for the recovery of ischemic stroke.
- Presenter
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- Cerise Rebecca Knakal, Senior, Psychology, Biology (Physiology)
- Mentor
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- Larry Zweifel, Pharmacology
- Session
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- Commons West
- Easel #27
- 12:45 PM to 2:15 PM
The amygdala, specifically the basolateral amygdala (BLA), has been implicated in fear-related processing and learning and is known to receive domaminergic input from the midbrain, although the specific nature of these connections is unclear. Mutations in functional glutamatergic NMDA receptors have previously been shown to impair phasic dopamine activity, leading to hindered fear-related learning and an onset of anxiety-like phenotypes following fear conditioning. To investigate how phasic dopamine activity modulates neuronal signaling in the BLA , I implanted mice with (controls) and without (KOs) a functional NMDA receptors in dopamine neurons with electrode microdrives bilaterally targeting the BLA and used in vivo electrophysiology to record neuronal activity during fear conditioning. The fear conditioning paradigm consists of 10 CS+ trials with a 10 second cue associated with a 0.3mA, 0.5 second foot shock and 10 CS- trials with a pulsed cue predicting the absence of a foot shock for a total of 20 trials in each session. Preliminary results show that the magnitude of the neuronal response to the unconditioned stimulus changes across days in the controls, while remaining constant in the KOs and that the KOs seem to show differences in tonic levels of activation during the trials compared to the controls. These results suggest that dopamine plays a role in modulating tonic activity in the BLA which may be implicated in influencing fear and anxiety related states.
- Presenter
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- Brad Anthony (Brad) Krajina, Senior, Chemical Engineering
- Mentor
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- Rene Overney, Chemical Engineering
- Session
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- Balcony
- Easel #114
- 12:45 PM to 2:15 PM
The building material of graphite, a two-dimensional material of single atomic width, possesses remarkable electrical, thermal, and mechanical properties. Due to its exceptional properties, research in graphene is actively pursued for applications such as electronics, solar-cell technology, and sensing materials. A critical question is how graphene may be combined with other materials (e.g. polymers) to form unique hybrid materials with novel functional properties. Thereby of great importance is the surface energy of single layer to multilayer graphene. Following this, we are exploring the surface energy of few-atomic-layer graphene as a function of the number of atomic layers present. To this end, we prepared few-atomic-layer graphene materials through a simple technique involving cleaving bulk graphite with tape and transferring the cleaved material to a suitable substrate. Such materials can be readily identified under optical microscope and further characterized by atomic force microscopy (AFM) — a scanning probe technology that provides nano-scale information of materials by probing the surface with a tip of atomic-scale width. After initial topographical identification, the surface energy and friction values of graphene were determined using Intrinsic Friction Analysis (IFA). This technique analyzes energetically the thermally active adhesive modes of interactions between the probing tip and the graphene surface. With knowledge of the surface energy of the probe, the sample surface energy can be deconvoluted from the energy information. We have employed this technique on few-layer graphene materials of multiple thicknesses. Our results reveal an energy-friction iso-line that is representative for planar systems with thermally active internal modes that are restricted to vibrational modes. While we observe for decreasing thickness increasing friction forces, the surface energies are decreasing from bulk graphite of 63 mJ/m2 to graphene of 48 mJ/m2.
- Presenter
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- Ila Kuntum, Junior, Materials Science & Engineering
- Mentors
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- Christine Luscombe, Materials Science & Engineering
- Katherine Mazzio, Materials Science & Engineering
- Session
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- Balcony
- Easel #93
- 12:45 PM to 2:15 PM
Solar energy is arguably the most promising source of renewable energy because it is thought to be both the cleanest and most abundant source. There are several types of solar cells including organic, inorganic, and hybrid organic-inorganic solar cells. While inorganic solar cells have high efficiencies, good charge carrier mobilities, and relatively long charge carrier times, their expensive production and materials competition with the microelectronics industry has kept their prices high. Organic solar cells are solution processable, applicable to flexible substrates, and have the promise of being relatively cheap to produce. However, their relatively low charge carrier mobilities and short exciton diffusion lengths prevent them from being used as an alternative to inorganic solar cells. Hybrid organic-inorganic solar cells have been introduced as a substitute to both organic and inorganic solar cells in order to overcome the short-comings of each. Inorganic semiconductors are used in hybrid photovoltaics as the acceptor in the solar cell due to the ease of changing the size and shape, and therefore the bandgap, of these semiconductors, which allows them to contribute to the photocurrent of the cell while enhancing the conductivity. This project addresses the synthesis of cadmium selenide (CdSe) nanotetrapods, which may facilitate control of direction of electron motion in the active layer of the cell. The reaction time, growth temperature, ligand type, and monomer concentration were used to control the synthesis, and the effects of each variable on the size and shape of the tetrapods were studied via transmission electron microscopy (TEM).
- Presenter
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- Natalie Marie (Natalie) Larson, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr NASA Space Grant Scholar, Washington Research Foundation Fellow
- Mentor
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- Brian Flinn, Materials Science & Engineering
- Session
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- MGH 241
- Easel #133
- 12:45 PM to 2:15 PM
A non-destructive inspection (NDI) technique that integrates mechanochromic fluorescent probe molecules into aerospace composite matrix resins was investigated. The NDI technique aims to allow quick and inexpensive inspection of aerospace composites that could reduce the need to over-design composite structures for undetected damage. This experiment was focused on determining the effect of the matrix resin mechanical properties on the activity of the fluorescent probe molecule. In the first step of this experiment, samples of epoxy (diglycidyl ether of bisphenol A (DGEBA)-diethylenetriamine (DETA)) functionalized with fluorescent probe molecules were fabricated. To change the mechanical properties of the epoxy samples, diglycidyl ether (polypropylene glycol) (DGE(PPG)) was added to the samples incrementally from 0-100 weight percent (wt%). To determine the effect of mechanical deformation on the probe in cured DGEBA/DGE(PPG)-DETA, fluorescence spectra were taken before and after incremental compression of the functionalized epoxy samples. The fluorescence testing revealed that the fluorescence activation increases with increasing compressive strain, strain energy, and stress, with a linear relation between fluorescence activation and strain. Furthermore, the fluorescence testing revealed that the fluorescence activation decreased as the modulus of the sample decreased, with the exception of the neat DGEBA-DETA sample. The fluorescence testing also revealed that, without exception, the fluorescence activation decreased as the glass transition temperature decreased and as the wt% DGE(PPG) increased, with no fluorescence activation for 40 wt% DGE(PPG) and above. These results suggest that the sample’s composition (wt% DGE(PPG)) and thermal properties (Tg) are more dominant factors affecting the probe’s response than the sample’s mechanical properties. Future work on this research will be aimed at determining why, on a molecular scale, the probe response decreases with increasing wt% DGE(PPG) and decreasing Tg.
- Presenter
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- Ashley Tsing-Yuen (Ashley) Lau, Sophomore, Biology (Physiology)
- Mentors
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- Jay Parrish, Biology
- Jiae Lee, Biology
- Session
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- Commons East
- Easel #82
- 12:45 PM to 2:15 PM
Neurons are specialized cells that receive and relay information throughout an organism, and the compartment that inputs the signal has multi-complex structures known as dendrites. The form of the dendrite is tightly regulated to neuron function; therefore, any abnormality that alters the structure of the dendritic arbor can lead to severe defects in neuronal function. However, the mechanisms of how dendrites develop and maintain their arborization are poorly understood. From a forward genetic screen for mutant alleles with progressive defects on dendrite patterning we identified one mutant allele that leads to a complete loss of terminal dendrites. We mapped this allele to a small genetic interval, and using complementation tests and DNA sequence analysis we identified Acsl (Acyl-CoA synthetase long-chain) as the gene affected by this mutation. Interestingly, Ascl is also associated with human X-linked mental retardation (XMR), but to date the role that Ascl plays in dendrite development has not been investigated. Here we report the phenotypic analysis of the Acsl mutant, effects of Acsl knock down in neurons, and our plans for functional analysis of Acsl in dendrite development.
- Presenter
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- Heather Fiona (Heather) Lee, Senior, Biology (Physiology)
- Mentors
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- Larry Zweifel, Pharmacology
- Graham Jones, Pharmacology, Psychiatry & Behavioral Sciences
- Session
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- Commons West
- Easel #26
- 12:45 PM to 2:15 PM
The neurotransmitter dopamine is a key component of the limbic sysem, which plays a critical role in emotional processing, learning and memory, and reward processing. Disruptions in dopamine synthesis, release, and reuptake underlie many neurological disorders, learning deficits, and diseases. Previous work from our lab established the importance of the glutamatergic NMDA (N-methyl-D-aspartate) receptor in maintaining normal phasic activity in dopamine neurons of the ventral tegmental area (VTA) and showed that mutations of this receptor cause deficits in fear-related learning, highlighting the importance of dopamine in fear-related learning. In this project we use in-vivo electrophysiology to record from dopamine neurons of the VTA during Pavlovian fear conditioning. The paradigm consists of two types of trials where one cue (CS+) is paired with a mild footshock (0.3mA, 0.5 sec), while the other trials utilize a cue (CS-) which predicts the absence of a footshock. Our preliminary data show plastic differences in neuronal activity patterns across training days associated with both conditioned and unconditioned stimuli, where initially there is increased activity in response to the fearful stimulus, but across days of conditioning, this response shifts to being associated with the conditioned stimulus.
- Presenter
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- Sin Yee (Cindy) Leung, Senior, Biology (Physiology)
- Mentors
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- William Mahoney, Pathology
- Jill Weyers, Pathology, Center for Cardiovascular Biology
- Session
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- Commons East
- Easel #51
- 12:45 PM to 2:15 PM
Cardiovascular disease is an epidemic, prevailing as the leading cause of death worldwide. One consequence of cardiovascular disease is a myocardial infarction (MI), or heart attack. An MI is caused by a blockage in the coronary arteries which cuts off the blood supply to a portion of the heart wall, forming nonfunctioning scar tissue. We are aiming to improve heart recovery post-MI by replacing scar tissue with functioning cardiac tissue through a cell engraftment therapy. Cardiac cell engraftment is difficult because cardiac cells die quickly due to lack of vascularization of the graft. We believe that by promoting vessel growth in grafts, we will improve therapeutic cardiac cell survival for better heart function during recovery. To study the coronary network’s ability to vascularize cell grafts, we inject skeletal muscle cells, which survive better than cardiac cells, into the heart wall post-MI. We observed vessel development in mice 14 days after MI and engraftment, and compared it to vessel development at other time points to better understand how the coronaries can vascularize cell grafts. To characterize the graft vasculature, I used histology to mark vessels and quantify vessel growth in the graft. My results shows that the coronary vasculature is able to expand and vascularize newly implanted tissue grafts post-MI. I detected capillaries as well as smooth muscle coated vessels in the graft suggesting vascular remodeling has occurred by 14 days post MI. My work establishes a baseline comparison for future research that will identify factors to increase the vascularization of graft tissue. We hope that promoting vessel growth will improve cell therapy methods for heart recovery to become applicable to clinical practice in the future.
- Presenter
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- Kiarra Rose (Kiarra) Levesque, Senior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
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- Commons West
- Easel #30
- 12:45 PM to 2:15 PM
Individuals with autism spectrum disorder (ASD) demonstrate impairment in communicating with others and responding to social cues appropriately. These impairments may extend to family members. The Broader Autism Phenotype (BAP) refers to relatives of individuals with ASD who exhibit impairments similar to those with ASD. BAP suggests that some traits of ASD may be inherited separately and exist in individuals without ASD. Social language impairment is consistently observed in individuals with ASD. Twins are useful in studying the genetic components of a disorder, because they share 50% (dizygotic) or 100% (monozygotic) of their genes. This study examined the presence of BAP traits in disconcordant twin pairs (where only one twin has an ASD diagnosis) compared to twin pairs with typical development. twins aged 7 to 30 years completed a 15-20 minute conversation with an experimenter, which was later coded for pragmatic (social) language abilities using the Pragmatic Language Scale (PRS). In the PRS, coders blind to diagnosis, rated individuals on skills such as eye contact, intonation, facial expression and reciprocity of conversation. First, analyses compared pragmatic language in three groups: (1) the twin with ASD, (2) the unaffected twin of the child with ASD, and (3) an age and gender matched typical twin with no family history of ASD. We expected that pragmatic language was most impaired in the ASD group compared to the typical group, with the unaffected twin showing intermediacy performance, suggesting that pragmatics are part of the broader phenotype. Next, we compared the relationship of symptom severity in the twin with ASD and the level of pragmatic language in their unaffected sibling. This study will provide insight as to whether pragmatic language skills are a part of the broader autism phenotype and the degree to which they are related to familial autism symptoms.
- Presenter
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- Hui Li, Junior, Exchange - Arts & Sciences
- Mentors
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- Jay Parrish, Biology
- Nan Jiang, Biology
- Session
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- Commons East
- Easel #81
- 12:45 PM to 2:15 PM
MicroRNAs (miRNAs) are crucial regulators of gene expression in plants and animals and play a critical role in many biological processes, including nervous system development. From our previous study of Drosophila melanogaster peripheral sensory neurons, we found that miRNA bantam is both necessary and sufficient in epithelial cells to initiate an epithelia-derived signaling pathway that regulates dendrite growth. Using miRNA sensors, which report the location on miRNA activity, we found that bantam activity is developmentally regulated in epithelial cells. We hypothesize that this developmental regulation of bantam activity is the result of transcriptional regulation of bantam, and we aim to investigate this using bantam transcriptional reporters. To this end, we are developing bantam transcriptional reporter constructs in which the bantam transcript has been replaced by different reporter genes, such as GFP or Luciferase, while preserving the cis-regulatory landscape. We will use these reporters to monitor bantam transcript levels over developmental time and, pending the outcome of these studies, we will use the reporters to identify trans-acting factors that regulate bantam transcription.
- Presenter
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- Matthew C. (Matt) Lind, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Nathan Sniadecki, Mechanical Engineering
- Session
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- Balcony
- Easel #88
- 12:45 PM to 2:15 PM
The mission of the Cell Biomechanics Lab led by Professor Nathan Sniadecki is to “understand how mechanics affects human biology and disease at the fundamental level of biological cells.” To do this, microstructures are created in this lab to interact with cells on their native micrometer length scales. These microstructures, made out of polydimethylsiloxane (PDMS), take the shape of micropost arrays on which cells are placed. When the cells attach to the posts they exert forces which bend the microposts. This bending is measured and used to calculate the forces generated by individual cells. It is important to measure these forces to fundamentally understand cell interactions within living tissue. This research increases the sensitivity and function of micropost arrays by decreasing the diameter (thus reducing the stiffness) of the posts to the nanometer scale using PDMS etchant, tetrabutylammonium fluoride (TBAF). With nanometer diameters, researchers gain the ability to measure forces produced by individual filopodia. Difficulties with this approach include ensuring homogenous etching of the arrays, and controlling the etch rate. This research overcomes both of these difficulties. To ensure a homogenous etch, the etchant is circulated evenly among the posts using a flow chamber. Etching rate is controlled by adjusting the etchant flow rate and time. Experiments are currently in progress. So far, etch rates have been determined for different flow rates using single block and post structures. This knowledge has been used to design the micropost array experiments. These experiments will be conducted in the coming weeks.
- Presenter
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- Keitaro MacHida, Senior, Psychology Mary Gates Scholar
- Mentor
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- Michael Murias, Psychiatry & Behavioral Sciences
- Session
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- Commons West
- Easel #11
- 12:45 PM to 2:15 PM
Superior spatial abilities in Autism Spectrum Disorder (ASD) are popularly associated with savant behaviors, and have been demonstrated in previous studies including tests of spatial intelligence. Our study examines participant's performance on a classical mental rotation task, which provides an objective measure of spatial ability. We seek to demonstrate how differences in reaction time (RT) and brain responses of adults with ASD differ from controls in this task. Previous research in typical individuals demonstrates that as the degree of rotation increases, participants are slower to make orientation decisions. These RT measures suggest individuals mentally rotate a second image to a reference image in order to make a decision. Our study tested age and IQ matched ASD and typical controls in a task that required a decision about the orientation of images of block alphabet letters. Participants were asked to decide whether the second of two images was identical to or a mirror of the first image. Images were presented at one of four angles. Dense array electroencephalography (EEG) and RT were recorded. Thirty-five male adults (17 in ASD, 18 in control) participated. RT, IQ, angle of images, and accuracy were variables for behavioral analysis. EEG data was analyzed in the time/frequency domain using open source and in-house software. EEG and RT measures from each trial of the task were compared based on subject group, types of images (normal or mirrored), and angle of images. Our analysis extends to include investigating brain activity prior to the pressing of the response key (the time that participants are making a decision). No general advantage in mean RT was seen in ASD group, however, high performance IQ (PIQ) participants in ASD group performed faster over the course of the experiment. This suggests high PIQ autistics may learn faster in this particular task.
- Presenters
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- Joseph Henry (Joe) Marcus, Senior, Biology (General) Mary Gates Scholar
- Samuel Evans (Sam) Reed, Senior, Biology (Ecology, Evolution & Conservation) Mary Gates Scholar
- Mentors
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- Benjamin Kerr, Biology
- Peter Conlin, Biology
- Session
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- MGH 241
- Easel #167
- 12:45 PM to 2:15 PM
The evolution of multicellularity is one of the most important yet least understood biological phenomena. What selective pressures drive this major evolutionary transition? To address this question, we use a theoretical approach to model the spatial properties of cell groups in a simulation entitled Tree-Multicellularity (TreeMu). In TreeMu a simple multicellular organism is represented as a graph, with nodes representing cells, and edges representing physical connections between cells. Like cells, nodes carry intrinsic attributes, such as reproduction, mutation and death rates; these dictate life processes and define an individual's fitness. Like multicellular groups, graphs have similar properties that emerge from individual contributions. When a node dies it splits the graph in two, analogous to group level reproduction. We explore how the evolution of a node's death rate affects multicellular growth. In the simulation we implement an evolutionary algorithm that selects for 'multicellular' graphs of large sizes by removing small groups from the population. Preliminary data supports a tradeoff between group size and reproduction. TreeMu provides a computational framework to explore the dynamics of multicellular evolution.
- Presenter
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- Jesus Martinez-Gomez, Sophomore, Pre-Sciences
- Mentor
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- Veronica Di Stilio, Biology
- Session
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- MGH 241
- Easel #160
- 12:45 PM to 2:15 PM
The ABC model of flower development explains the patterning of organs along the flower axis. Involving mostly MADS box genes, that partake in determining flora organ identity, this model has been the botanical counterpart to the Homeobox genes which participate in the morphogenesis of animals. The model predicts the production of the four floral organs sepals, petals, stamen and carpels, through various combination of the A, B, and C-class genes. The flowering plant species Thalictrum thalictroides, in the buttercup family Ranunculaceae, belongs to an interesting lineage that is sister to all other eudicots, including the model system Arabidopsis thaliana. T. thalictroides flowers consist of three types of organs: sepals, stamens and carpels, lacking petals. However, the sepals express a petaloid morphology, being large and white or pink. I will be using a forward genetics approach to study a horticultural mutant of T. thalictroides, ‘Betty Blake.’ Its phenotype consists of multiple whorls of non-petaloid (green) sepals and multiple whorls of carpels, resembling B-class gene mutants. We hypothesize that the reason for the lack of stamens, the extra carpels and non-petaloid sepals in ‘Betty Blake’ is a mutation in one or more of the B-class genes. The four B-class candidate genes belong to the MADS box gene family and function in petal and stamen identity. I will be sequencing and analyzing the entire genomic locus of 8 candidate genes, by means of basic molecular biology techniques. A mutation could cause a loss of B-class function potentially, resulting in a homeotic conversion from stamen to carpels and sepals. Molecular dissection of this mutant will contribute to understanding the degree of conservation of stamen identity genes across divergent flowering plants, and to test whether sub-functionalization in the B class gene lineage contributes to petaloidy of sepals.
- Presenters
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- Edin Mehic, Senior, Bioengineering Mary Gates Scholar
- Talia Suner, Junior, Neuroscience, Biochemistry NASA Space Grant Scholar
- Mentor
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- Pierre Mourad, Neurological Surgery
- Session
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- Commons East
- Easel #65
- 12:45 PM to 2:15 PM
Ultrasonic neuromodulation is the process of stimulating different neural pathways in the brain through the use of transcranially delivered ultrasound in order to induce clinically relevant emotional, cognitive, physical or behavioral reactions. My research goal is to find out if it is possible to add anatomical specificity to current neuromodulation practice through the use of modulated focused ultrasound (mFU), where 'modulated' refers to adding complex temporal structure to the waveform to optimize neuromodulation. Since mFU has a small focus relative to the brain, the acoustic power from the ultrasound can be moved within the brain; previous experiments have used unfocused ultrasound which sends ultrasound through the entire brain. We hypothesize that we can map varying physical reactions through stimulation of different parts of the brain, with initial emphasis on the motor cortex because stimulation there produces readily observable results. With lightly anesthetized mice as our subjects, and always delivering ultrasound through the skin and skull, we began neuromodulation with unfocused transducers to transmit our ultrasound. This critical step was done to determine the optimal intensity, waveform shape and carrier frequency of ultrasound that created robust, observable effects. Next we translated these ultrasound parameters to our mFU transducer. The current stage of the process includes moving through different parts of each hemisphere and recording the associated motor response such as leg movements and tail flicks. We have already seen a change in activity between activating the front, middle, and rear regions of the brain, as well as dosing effects. Going forward, we intend to see if we could produce varied motor movements with greater spatial resolution using our focused ultrasound across a predefined grid atop the brain. Further studies will also change the applied stimulation intensity. Clinical implications for neuromodulation research include retraining brain function after injury and improving current therapeutics.
- Presenter
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- Jeanette Marie (Jeanette) Miller, Senior, Interdisciplinary Arts & Sciences (Psychology), UW Tacoma
- Mentor
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- Stephen Ross, Interdisciplinary Arts & Sciences (Tacoma Campus), University of Washington, Tacoma
- Session
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- Commons West
- Easel #15
- 12:45 PM to 2:15 PM
Although eyewitness testimony is a critical element in criminal investigation, decades of research have demonstrated the fallibility of eyewitness memory. Among the reforms proposed to minimize eyewitness errors is the recommendation that investigators instruct eyewitnesses that “individuals depicted in lineup photos may not appear exactly as they did on the date of the incident”. Although expectations were that this appearance change instruction (ACI) would enhance the quality of the eyewitness decision, recent research suggests that the instruction may actually result in more mistaken identifications. Two theories were proposed to account for this finding. The first suggests that the increase in mistaken identifications caused by the ACI is a result of witnesses mental transforming the individuals in the lineup to imagine what they would look like if they were more similar to the perpetrator. The second theory proposes that the increased mistaken identifications are a product of witnesses simply becoming more willing to choose someone from the lineup as a result of being told that the true perpetrator may not look the same as their memory. The present study was designed to test the first hypothesis using a novel secondary recognition task paradigm. Relying on data collected from 120 college students, we evaluated whether the ACI encouraged witnesses to engage in a “mental transformation” of the lineup members when viewing a lineup. Part 1 of the study involved showing participants photographs of individuals and then testing their memory for those individuals with simultaneous lineups. In Part 2, witness’s memory for the lineup members themselves was tested. Overall, results did not support the “mental transformation” hypothesis. However, given that participants performed at chance levels in the Part 2 task, it is possible that the null results are due to task difficulty.
- Presenter
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- Andrew Millspaugh, Senior, Physics, Bioengineering Howard Hughes Scholar, Mary Gates Scholar
- Mentor
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- Daniel Ratner, Bioengineering
- Session
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- Commons East
- Easel #73
- 12:45 PM to 2:15 PM
Medical diagnostic device development has been, in recent history, focused largely on paper-based diagnostics. Such devices offer incredibly low per patient cost with the downside of poor sensitivity and minimal ability to multiplex, or detect many different compounds simultaneously. New technologies which leverage exceedingly efficient silicon manufacturing have the potential to approach the cost of paper diagnostics with increased sensitivity and extensive multiplexing. This project aims to develop one such technology, silicon photonics. Using existing manufacturing technologies, silicon photonic sensing measures analyte mass accumulation through dielectric shift by taking advantage of the evanescent field of electromagnetic radiation passed through a silicon wafer. Aided by unique binding chemistries, silicon photonic devices are capable of highly specific analyte detection. The current stage in this project is focused on developing tools, the most notable being a rapid prototyping setup for testing chip design. The setup automates the interaction of a variety of necessary hardware components including fluidic pumps, movable stages, a microscope, and an infrared laser. By using such a rapid prototyping setup, it is hoped that a chip design that is extremely condusive to medical diagnostics will be developed and brought to cost effective levels.
- Presenter
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- Merissa Elizabeth (Merissa) Mitchell, Junior, Anthropology
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #10
- 12:45 PM to 2:15 PM
I am interested in discovering the effects of tough love motivation fed from coaches to athletes. I view "tough love" motivation as an expression used by one person (i.e. coach) to treat another person (i.e. athlete) harshly, with the underlying intent to benefit this person (i.e. athlete) in the long run. For my research, I will primarily focus on the mainstream college sports of men's basketball and football. I wonder to what extent tough love motivation from coach to athlete effects an athlete's performance, and what are the resulting repercussions for their coach-athlete relationship as well as for the athlete's future? To supplement my research, I relate to recent research conducted by Renata Baric and Valentin Bucik, entitled Motivational Differences in Athletes Trained by Coaches of Different Motivational and Leadership Profiles (2009). In investigating my research question, I will use the following anthropological methods: photovoice, discourse analysis, and interviewing. By my results, I intend to uncover the impact of tough love motivation in college level sports. I assume its effects are not only lasting but also detrimental for an athlete's performance and future. Depending upon my results, I hope to provide college coaches (present-day and future) with the encouragement to adjust their coaching profiles, if need be. Finally, I envision my research will serve as a resource for coaches to refer to, in their effort to shape, mend, and/or strengthen coach-athlete relationship(s), and consequently, in refining their athletes' performances not only in the game but also in their futures.
- Presenter
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- Christopher Bruce (Chris) Montgomery, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Christine Luscombe, Materials Science & Engineering
- Ken Okamoto, Materials Science & Engineering
- Session
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- MGH 241
- Easel #138
- 12:45 PM to 2:15 PM
Organic electronics is a growing area of research that investigates the properties and applications of conjugated polymers and conductive small molecules. Devices made from organic electronic materials can be flexible, inexpensive to process, and have lower weight compared to inorganic devices. Prominent synthetic techniques for conjugated polymers, including the Suzuki reaction, Heck reaction, and Kumada coupling, utilize a palladium or nickel complex as the catalyst. When the reaction completes, organometallic molecules and metal nanoparticles remain stuck in the polymer, decreasing the efficiency of resulting devices by acting as charge trappers or photo quenchers. The potential commercial success of organic electronics is highly dependent on their efficiency, and so the impurities need to be removed. A palladium-catalyzed model Suzuki coupling reaction of bromobenzene and phenylboronic acid was analyzed by 31P-NMR both before and after the post-synthetic addition of thiuram disulfide (TMTD). Pd(PPh3)2Br2 dibromide was present in the solution prior to the post-synthetic disulfide addition, but not after. When TMTD or diphenyl disulfide were added directly to metal catalyst in chloroform, the resulting product precipitated out; the solubility of the product was different from the reactants. The change in solubility indicates that disulfide molecules can behave as metal scavenger for residual palladium or nickel catalyst. In order to restore the performance of organic polymers, scavenger molecules are used post-synthesis. This additional step isolates palladium or nickel atoms and changes their solubility, allowing them to be separated from the polymer. The performance of disulfide-based metal scavengers added to catalyst-metal-contaminated conjugated polymers is discussed.
- Presenter
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- Kelly Mooney, Senior, Interdisciplinary Arts & Sciences (Ethnic, Gender & Labor Studies), UW Tacoma, Interdisciplinary Arts & Sciences (Psychology), UW Tacoma
- Mentor
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- Stephen Ross, Interdisciplinary Arts & Sciences (Tacoma Campus), University of Washington, Tacoma
- Session
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- Commons West
- Easel #16
- 12:45 PM to 2:15 PM
Since the introduction of DNA testing in 1989, post-conviction DNA testing has exonerated over 300 individuals in the United States who were wrongly convicted (Innocence Project, 2013). Evaluations of these cases have revealed that the single greatest contributor to these errors has been mistaken eyewitness identification (Garrett, 2011). Recommendations proposed to improve eyewitness decision-making in identification procedures include the use of unbiased instructions, the “appearance change instruction” (ACI; reminding the witness that the perpetrator may look different now than s/he did during the crime), and sequential presentation of lineup members. Past research on unbiased instructions and sequential presentation has shown that these procedures encourage more conservative decision processes which lead to fewer false identifications, but also fewer correct identifications. In contrast, recent research in our lab has indicated that the ACI appears to have the opposite effect; the instruction generates more liberal choices that lead to more correct, but also false identifications. Given the effects of these recommended procedures, the present research examines the relative influence of these three procedures on witness decisions in photographic lineups. A 2 (unbiased instructions: yes/no) x 2 (ACI: yes/no) x 2 (lineup presentation: simultaneous/sequential) between-subjects factorial design was used. Participants (N=121) viewed photographs of individuals and later had their memory tested with both target-present and target-absent photoarrays. Preliminary analyses indicate that, as expected, sequential presentation resulted in more conservative decision-making whereas the ACI produced less conservative decisions. There was no effect of unbiased instructions on decisions. This poster will present complete results on all participant data in relation to the main effects of and interactions amongst the ACI, unbiased instructions, and sequential presentation on witness’ decisions. These results will provide further information regarding the use of the ACI and its’ relative contribution to improving the collection of eyewitness evidence.
- Presenter
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- Robert Thomas (Robert) Morris, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Brian Flinn, Materials Science & Engineering
- Session
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- MGH 241
- Easel #134
- 12:45 PM to 2:15 PM
My senior research project consisted of the manufacturing and development of a composite structure for the encasement of the cooling pump for UW Eco Car II. The purpose of creating this structure was to discover the relationship between nanoscale elements (voids, impurities, toughening particles) and the mechanical performance of the composite while maintaining an acceptable strength-to-weight ratio. The composite box was constructed using S-glass fiber plies and a two-part epoxy resin matrix. The wetting of the plies was done using a hand lay up technique. Once each ply was fully impregnated with the resin matrix, the plies were then transferred onto a wood tool that was covered in fluorinated ethylene propylene (FEP). Subsequent wrapping of perforated FEP, bleeder material, and another layer of FEP was bagged under vacuum and left to cure at room temperature. Although this object was cured at room temperature, the use of an autoclave could enhance the mechanical stability of the composite. The combination of heat and pressure would eliminate nanoscale impurities such as voids or semi-crystalline regions as well as promote adhesion of the matrix and fibers. Moreover, the addition of thermoplastic nanoparticles such as polyester could effectively reduce interlaminar shear. Further analysis was conducted into finding the optimal size of these particles to maximize the performance of the composite structure. Through controlled techniques and a proper cure time, a uniform composite casing was fabricated and mounted in the trunk of the Eco Car II. The introduction of thermoplastic elastomeric nanoparticles into the epoxy resin matrix during the mixing process could effectively toughen the composite and would require an autoclave autoclave to ensure the particles were co-continuous within the matrix. At this stage, the thermoset keeps its high glass transition temperature while the thermoplastic increases toughness.
- Presenter
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- Robin Mumm, Sophomore, Physics , Seattle Central College
- Mentor
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- Rainer Heller, Engineering, Physics, Seattle Central College
- Session
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- Balcony
- Easel #100
- 12:45 PM to 2:15 PM
The purpose of the double slit experiment is to observe the wave-particle duality of light. When a steady stream of photons hits a double slit, the resulting interference pattern is a clear indicator of the wave nature of light. However, if at a given time only a few photons hit the double slit and the signal is recorded over time, one can observe both the particle and wave nature of light: individual particles (particle nature) are recorded over time while their sum will eventually produce the familiar interference pattern (wave nature). The experimental setup uses light filters to reduce the intensity of a laser beam to just a trickle of photons. These photons, after passing through a double slit, slowly produce an interference pattern on a detector. The detector is a digital video recorder set up to record photon hits. The video frames are superimposed to show the production of an interference pattern over time. The double slit experiment has been done numerous times and in different forms. The experiment conducted here does not produce, but confirm previous results using a new experimental setup. The challenge will be to successfully show the wave-particle duality of light with readily available equipment to allow for a straightforward demonstration to future students. The enormous historical importance of the double slit experiment lies in the fact that it is at the heart of quantum mechanics, a field of physics viewed as challenging yet vitally important to the future of human technological advancements.
- Presenter
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- Sean Austin (Sean) Murphy, Junior, Bioengineering Mary Gates Scholar
- Mentors
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- Scott Lundy, Bioengineering
- Michael Laflamme, Pathology
- Session
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- Commons East
- Easel #49
- 12:45 PM to 2:15 PM
Cardiovascular disease is the leading cause of death worldwide, and current treatments for heart failure are limited to slowing the disease progression or transplanting a donor heart. One potential approach to restore heart function is to transplant human embryonic stem cell-derived cardiomyocytes (hESC-CMs). An independent and similarly promising approach is to overexpress the enzyme ribonucleotide reductase (RR), the enzyme responsible for the production of the small molecule deoxy-ATP, which has been previously shown to improve contractility and diffuse between cardiomyocytes via gap junctions. We hypothesize that by overexpressing RR in hESC-CMs and then transplanting the latter into infarcted hearts, we will improve global cardiac function by increasing dATP content throughout the myocardium. To begin testing this hypothesis, I will test the efficacy of an RR adenovirus in hESC-CMs in vitro using quantitative PCR and immunostaining, and I will then correlate the subsequent improvement in fractional shortening following in vivo transplantation to the amount of successfully engrafted cells. To date, I have successfully developed an immunofluorescence staining protocol for RR. I am currently working on designing an immunohistochemistry protocol to identify graft tissue and stain for RR and GFP and localize RR in relation to the infarct. After confirming the protocol, I plan to apply it to the fixed rat heart slices to assist in the proof of concept of the transplantation of hESC-CMs overexpressing RR as a novel therapeutic method.
- Presenter
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- Andrew Vu (Andrew) Nguyen, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Sei-Hum Jang, Materials Science & Engineering
- Jeffrey Chih-Yeh Yang, Materials Science & Engineering
- Session
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- MGH 241
- Easel #135
- 12:45 PM to 2:15 PM
Titanium Oxide (TiO2) nanotubes, nanowires, and coreshell structures have the potential to be implemented in new unique devices. TiO2 has a variety of gas-sensing, photovoltaic, and semiconductor properties. TiO2 has multiple forms such as TiO2(B) and anatase, which could be surface modified. These forms are synthesized depending on the hydrothermal treatment. The ultimate goal was to create a thin film, out of nanowires, for a top contact field effect transistor. For an efficient top contract, the film must be homogeneous and be composed of one or two layers of nanowire. The creation of nanowires started with anatase or p25 combined with a 10 M NaOH solution that underwent a hydrothermal process for 48 hours. With two autoclaves, two reactions can be done simultaneously. Keeping one reaction constant as control, the other autoclave had its parameters slightly modified. The modifications in thermal ramp rate, solution molarity, hydrothermal duration, and amount of starting material, helped understand the titante nanostructures and growth mechanism. 170°F was the established temperature where nanotubes started turning into nanowires while 200°F was the control. There were several treatments, post-hydrothermal, to acquire TiO2(B). An ion-exchange transformed Na2Ti3O7 into H2Ti3O7 then calcination produced TiO2-B. With these materials, several methods, such as spin-coating and drop-casting, were tested to create a thin film. For a consistent film, the nanowires must be uniform and the fabrication process reproducable.
- Presenter
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- Daniel James Noteboom, Junior, Computer Engineering NASA Space Grant Scholar
- Mentor
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- Rachel Horak, Oceanography
- Session
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- MGH 241
- Easel #150
- 12:45 PM to 2:15 PM
Nitrogen (N) is an essential element of life that organisms need to make DNA and proteins. Unlike other essential elements such as phosphorous, nitrogen takes many different forms (NH4+, N2O, NO, NO2-, NO3, N2) which are constantly cycling in the recently revised oceanic nitrogen cycle. One group in the Archaeal domain of life, ammonium-oxidizing Archaea (AOA), has recently been discovered to be a key player in the oceanic nitrogen cycle. In this cycle, Archaea oxidize ammonium (NH4+) into nitrite (NO2-) in a process called nitrification. We hypothesized that different abiotic factors such as copper, light, and temperature regulate the physiology and depth distribution of the AOA. To test our hypothesis, we conducted 15NH4+-oxidation experiments in July 2012 aboard the R/V Clifford A. Barnes in Hood Canal, Washington. Samples of seawater were filled in bottles, spiked with 15NH4+, and incubated for 10 hours. We measured the oxidation of the 15N isotope using mass spectrometry, and compared the rates for control treatments to rates for treatments amended by copper (Cu), light, and other factors. 15NH4+-oxidation rates were consistently low at the surface, increased until 30-40 m, and decreased to 115 m depth. Our experiments clearly showed light inhibition of 15NH4+-oxidation, but the data did not clearly determine whether sunlight-produced peroxides inhibited AOA. Copper additions in Cu-deplete regions increased nitrification, possibly because the key enzyme in ammonium oxidation (amoA) is Cu-dependent. TETA, a chelator that binds Cu, did not show any effect when added during incubations. All together our results suggest that Archaea are Cu-limited, but may store Cu in small amounts. This project is part of a larger interdisciplinary effort to understand the oceanic microbes and the impacts they have on biodiversity and greenhouse gases such as N2O and CO2. Future studies in 2013 will extend these experiments to the open ocean.
- Presenter
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- G. (Guillermo) Ochovo Ubeda-Portugues, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Carolina Vinado, Materials Science & Engineering
- Jihui Yang, Materials Science & Engineering
- Session
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- Balcony
- Easel #90
- 12:45 PM to 2:15 PM
Currently, one of the main challenges is the development of new technologies for the storage of energy. Hence, there exists a particular interest for a low-cost, safe, rechargeable battery with high capacity, voltage and rate capability. My project consists of developing a better understanding of the charge-discharge cycles and the factors constraining the electrochemical performance of the active material within a lithium-ion battery. Electrode efficiency depends highly on the active materials used. The chemical composition of the cathode material is one of the keys to optimize the performance of these batteries where three metal salts (Co, Ni & Mn) are combined under the following formula: (1-z) Li [Li(1⁄3)Mn(2⁄3) ] O2 - (z) Li [Mn(0.5-y)Ni(0.5-y)Co(2y)] O2. Each metal has major downsides such as high cost, toxicity or reversibility loss, but they also offer high capacity or stability. In order to maximize the performance of the cell, an optimized battery must comprise a particular percentage of each metal. Under the supervision of Carolina Vinado, we have successfully synthetized several lithium-ion rechargeable coin cells which are currently being tested for reliability. For our first batch, we used an equivalent amount of cobalt and nickel, assigning the values of 0.4 and 1.6 for z and y respectively. The resultant formula is shown: Li1.20Mn0.54Ni0.13Co0.13O2. The next phase of the project involves the modification of the cathode’s chemical composition for testing and future analysis. In addition, we are planning to analyze the surface of the cathode using Transmission Electron Microscopy (TEM). This facilitates the examination of the interface morphology, which after various charge/discharge cycles may develop defects on its surface. It is essential to understand these surface anomalies as they critically affect the battery’s ability to perform effectively.
- Presenter
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- Senteara Orwig, Senior, History, Anthropology
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #42
- 12:45 PM to 2:15 PM
For my research, I was interested in the growing popularity of belly dancing in the United States, with a focus on misconceptions, stigmas, stereotypes, and the benefits that have attracted women (and some men who take classes and perform) to belly dance. I researched these ideas that contribute to and surround belly dancing because of my personal experience as a local Seattle Belly Dancer. I was interested in both the reasons for the increase of interest and the stereotypes that need debunking. My question is: why have cultural perceptions of belly dancing shifted from a stereotype of sexualized dance to one of female empowerment and growing popularity? In order to answer this question I used participant observations, discourse analysis, photovoice and articles from both the media and scholarly. Rachel Kraus’s article titled “We are not Strippers: How Belly Dancers Manage a (Soft) Stigmatized Serious Leisure Activity” was useful in quoting and comparing her research on the stigma’s of belly dancers. From my research I found female empowerment about their bodies to be one of the core reasons for the growing popularity and also found stigma’s of the dance form being for male entertainment, which is a fallacy. The research helped me become more aware of my community and its complexities.
- Presenter
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- Zack Suriya (Zack) Oyafuso, Senior, Aquatic & Fishery Sciences
- Mentor
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- Julie Keister, Oceanography
- Session
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- Balcony
- Easel #102
- 12:45 PM to 2:15 PM
Hypoxia is the term used in aquatic systems to describe low concentrations of dissolved oxygen (i.e. ≤ 2 mg O2¬/ml). Over the past 30 years, the intensity and duration of hypoxia has increased worldwide, with notable examples in the Gulf of Mexico, Chesapeake Bay, and Hood Canal, WA. Increased nutrient pollution from anthropogenic sources like agricultural fertilizers and raw sewage is contributing to the increased phenomenon of intense hypoxia in aquatic systems. Low dissolved oxygen is not only a major stressor to fishes, but may also be responsible for dramatic ecosystem shifts with respect to energy flows through the food chain. Zooplankton communities, an important energy source for fishes, were analyzed in Hood Canal, WA in relation to summer hypoxia. Zooplankton abundance, taxonomic composition, biomass, and length distributions were compared between areas of Hood Canal that experienced moderate versus intense hypoxia at the beginning and end of the summer hypoxia season. The goal of the project is to track differences in zooplankton composition between the two sites, with intense hypoxia relating to a shift towards smaller types of zooplankton and more gelatinous organisms relative to the site with moderate hypoxia. The size of zooplankton will potentially affect the efficiency of energy transfer between zooplankton and fishes, with larger zooplankton transferring more energy relative to smaller zooplankton. Gelatinous organisms like jellyfish, siphonophores, and ctenophores generally have lower oxygen requirements and few predators. Thus, an increase in these organisms is a ‘trophic dead end,’ shunting energy that may otherwise contribute towards fish growth. Analyzing trophic changes in Hood Canal in response to hypoxia will provide insight into major ecosystem changes occurring as a result of anthropogenic perturbations.
- Presenter
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- Anthony Matthew (Anthony) Paat, Senior, Astronomy, Physics
- Mentor
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- Leslie Hebb, Astronomy
- Session
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- Balcony
- Easel #98
- 12:45 PM to 2:15 PM
MML 53 is a system of young stars which, in 2010, was discovered to be an eclipsing binary. A detailed analysis of the brightness changes and velocity variations of an eclipsing binary provides precise measurements of the masses, radii, temperatures, and luminosities of two stars with the same age and chemical composition. Thus, eclipsing binary stars are extremely important astronomical systems that are used to test our understanding of the structure and evolution of stars. Despite their importance, young eclipsing binaries, like MML 53, are rare. We applied the PHOEBE (Physics of Eclipsing Binaries) software to the observed multi-wavelength time series photometry data of MML 53 to derive precise values for the combined radii of the two stars, the effective temperature of the secondary star, and reasonable locations for the starspots on both the primary and secondary stars. Using a Markov chain Monte Carlo analysis (eMCMC Hammer) we ran over 60000 PHOEBE models which has allowed us to explore correlations between various parameters and derive realistic uncertainties on the final fundamental properties of these two young stars.
- Presenter
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- Joshuel Arce (Josh) Pahang, Junior, Bioengineering Mary Gates Scholar
- Mentors
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- Suzie Pun, Bioengineering
- Joan Go Schellinger, Bioengineering
- Session
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- Commons East
- Easel #76
- 12:45 PM to 2:15 PM
It has been hypothesized that effective treatment of neurodegenerative diseases, such as Huntington’s Disease and Alzheimer’s, may be possible through the manipulation of neural stem cells to divide and replenish afflicted neuronal cell populations. A crucial component of this treatment would be the creation of a vehicle for the efficient delivery of stimulating genetic material into target cells. Prospective virus-based vectors accomplish this by making use of a recombinant virus and its natural ability for gene transfer. These viral vectors, while inherently effective, have significant safety issues with the possibility of eliciting harmful immune responses. Peptide-based copolymers are a promising non-viral alternative for delivery systems. While safer, these synthetic vectors have thus far proven less efficient. One problem is lack of consistent cell membrane penetration, preventing the therapeutics from reaching areas within the cell where they would come into effect. Our laboratory has recently incorporating the membrane-lytic peptide melittin (a molecule derived from bee venom) into our base DNA-binding peptide-based polymers. The melittin-functionalized materials were shown to increase gene delivery efficiency by at least 10-fold compared to control materials both in vitro and by injection into mouse brain. This current study seeks to develop a multifunctional delivery system by incorporating the neuronal-targeting peptide “Tet1,” for specialized treatment of neurodegenerative diseases. Previous work showed that conjugation of Tet1 to control polymers results in increased transfer specificity to neuronal cells in vivo. Potentially, Tet1 and melittin can synergize to further improve gene delivery to the central nervous system.
- Presenters
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- Heena Panjwani, Sophomore, Psychology
- Anjli Ajit (Anjli) Shah, Junior, Psychology
- Mentor
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- Sara Jane Webb, Psychiatry & Behavioral Sciences, Seattle Children's Research Institute
- Session
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- Commons West
- Easel #29
- 12:45 PM to 2:15 PM
Autism Spectrum Disorder (ASD) is characterized by deficits in communication, social skills, and repetitive behaviors. Understanding the risk factors in early childhood that lead to the diagnosis of autism is an important area of research. Specifically, researchers are trying to understand how communication development differs in children who go on to develop autism in comparison to those that do not. Previous research has shown that 18.7% of infants, who have at least one older sibling with ASD, develop autism. In this current study, two groups of infants between the ages of six and twenty-four months were tracked longitudinally: high-risk infants who have an older sibling with ASD and low risk infants who have no family history of ASD. The Communication and Symbolic Behavior Scales (CSBS) protocol was used to identify various communication modes used by each infant at 12 and 18 months of age. The videotaped interactions between the infant, clinician, and parent were coded offline by a group of trained undergraduates. The following communicative acts were defined and coded: (1) behavior regulation: the infant’s attempt to control some behavior of an individual around him/her; (2): social interaction: the infant’s ability to bring attention to him/herself; and (3) joint attention: the infant’s ability to bring attention to an object. Our aim is to explore differences between rates of communicative acts in high risk and low risk infants at 12 months of age. Previous research suggests that children with ASD are less likely to draw the attention of others to objects or events. We hypothesize that high risk infants will display significantly lower rates of communication acts in all three domains when compared to their low risk peers. This study will contribute to a better understanding of possible deficits in early communication in this high-risk population, leading to earlier intervention opportunities.
- Presenter
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- Beth Bingjie (Bingjie) Pecha, Senior, Biology (Molecular, Cellular & Developmental), Public Health-Global Health Mary Gates Scholar
- Mentors
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- Julie Overbaugh, Microbiology
- Leslie Goo, Global Health
- Session
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- Commons East
- Easel #85
- 12:45 PM to 2:15 PM
Neutralizing antibodies, which prevent entry of the HIV virus into a host cell by binding to the HIV envelope and neutralizing the biological effects of the virus, is an important focus of HIV vaccine design. It is hypothesized that these neutralizing antibodies may protect against initial infection from HIV if they are elicited by vaccination and are thus present at the time of virus exposure. The high rate of HIV mutation results in an enormous number of HIV variants circulating in the human population. Thus, an effective neutralizing antibody-based vaccine must be broad and potent. In order to understand how to create factors that elicit broadly neutralizing antibodies (bNAbs), it is important to identify and map regions of the viral envelope important for recognition by bNAbs. The best way to map the molecular basis is to identify two closely related variants that are or are not susceptible to neutralization by a certain virus and identify the regions that differ between the two variants. PGT128- is a HIV-1 monoclonal antibody that has been identified as having a broad neutralizing activity that would be desirable for a vaccine to elicit. Our lab previously found that longitudinal viruses from a HIV-1 infected patient, QA255, across 560 days post infection (dpi) display increasing ability to be neutralized by PGT128. PGT128 recognition has recently been found to depend on residue N332 of the V3 envelope region of HIV. As this residue is intact in QA255 viruses over time, there are additional determinants of sensitivity to PGT128. We found that chimeric sequences containing 560 dpi DNA in the V1-C3 region of the HIV envelope sequence show more sensitivity to PGT128 compared to chimeric sequences from earlier time points. This result suggests that amino acids in the V1-C3 region are important for PGT128 sensitivity.
- Presenter
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- Alejandro Ramon (Alejandro) Pena, Senior, Psychology
- Mentors
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- John Oliver Siy, Psychology
- Sapna Cheryan, Psychology
- Session
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- Commons West
- Easel #18
- 12:45 PM to 2:15 PM
Being the target of a positive stereotype (e.g., “women are nurturing”) can elicit many negative effects. The current study investigates the influence of positive stereotypes on women’s math performance and their identification with science, technology, engineering, and math (STEM) fields. In the present study, some women were the target of a positive stereotype before being asked to take a math test. Women who were positively stereotyped did not differ in their math performance compared to women who were not the target of a positive stereotype. However, positively stereotyped women felt that it was less important for them to do well in math than women who were not the target of a positive stereotype. These results suggest that positive stereotypes may lead women to identify less with STEM fields, an important predictor of success or retention in a field, and may be a factor in perpetuating gender disparities.
- Presenter
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- Tiep Hoang Pham, Senior, Chemical Engr: Nanosci & Molecular Engr
- Mentors
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- Rene Overney, Chemical Engineering
- Lakshmi Suhasini Kocherlakota, Chemical Engineering
- Session
-
- Balcony
- Easel #111
- 12:45 PM to 2:15 PM
CO2 separation from flue gases constitutes to nearly 40% of the CO2 emission in the United States. Developments resulting from this work address factors key to increasing the transport properties in polymer membrane systems. In particular, this work explores method to engineer porous structure to enhance the selectivity of polymeric membrane. The polymer system of interest in this study is poly(l-trimethylsilyl-1-propyne) (PTMSP), a glassy polymer of extraordinary high free volume compared to conventional polymers. It is “reverse-selective” for CO2 separation from flue gases such as nitrogen or hydrogen, i.e., transports CO2 gas faster in respect to lighter flue gases. Based on prior studies that showed that enhanced transport properties for PTMSP if constrained to thin films, here we present our data for PTMSP if constrained in nanoporous functionalized anopore alumina oxides (AAO) “sieve” membranes. Impregnation was achieved via vacuum solution impregnation. The overall CO2 permeability of impregnated membranes was found to be ~80,000 Barrer, which is almost two times higher than that of bulk PTMSP membranes. Selectivities of CO2/Helium and CO2/Nitrogen in impregnated membranes were found to be ~7.0 and 9.0, respectively; these are also noticeably higher than the corresponding selectivities of 6.0 and 6.6 found in bulk membranes. Furthermore, we investigated the temporal stability of these membranes that are notorious for their fast aging in the form of ultrathin films. The origin for physical aging is the collapse of the free volume. A two week aging study of PTMSP revealed a significantly slowed down physical aging process if confined in nanoporous AAO by about a factor of 20 over thin films. The exposure to the radial constraint within the pores helped stabilize the free volume and reduce the occurrence of free volume collapse.
- Presenters
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- Daniel (Dan) Polking Jr, Senior, Chemistry, The Evergreen State College
- Tristan Workman, Senior, Biology, The Evergreen State College
- Mentor
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- Peter Pessiki, Chemistry, The Evergreen State College
- Session
-
- Balcony
- Easel #116
- 12:45 PM to 2:15 PM
Alternative energy sources have been becoming a greater necessity as fossil fuels become higher in demand and pollution endangers the world. Dye-sensitized solar cells have been of increasing interest in the last twenty years as a possible low-cost and efficient alternative to conventional fuel sources. Porphyrins are synthetic analogs of chlorophyll, the molecule responsible for molecular oxygen. Our group has synthesized a number of porphyrins and constructed solar cells using these compounds as the light harvesting pigments necessary to produce energy. Our goal is to determine the change in energy gathering potential and binding capability of the porphyrins to the cells based on the substituent groups bound to the parent molecule. These results will be presented as well as our progress toward optimizing a working dye-sensitized solar cell.
- Presenter
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- Anthony Miranda (Anthony) Recidoro, Senior, Biology (Molecular, Cellular & Developmental)
- Mentor
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- Ronald Kwon, Orthopaedics & Sports Medicine, UW School of Medicine/Institute for Stem Cell and Regenerative Medicine
- Session
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- MGH 241
- Easel #168
- 12:45 PM to 2:15 PM
Only a few organisms possess the capacity to regenerate limbs and appendages from development into adulthood. Danio rerio, or zebrafish, are recognized as a powerful model for investigating regenerative processes. For example, following amputation of the tail fin, zebrafish rapidly restore lost bone, joints, nerves, and blood vessels within a few weeks. My research is focused on determining neuronal processes that contribute to the ability of zebrafish to regenerate their fins. My experiments have consisted of amputating the tail fin, and tracking fin growth and bone mineralization. To inhibit neuronal function, I developed an inducible model neuronal impairment by injecting the fins with Botulinum toxin type B. Data is analyzed through pictorial documentation, bone staining, image analysis, and microCT scanning. Preliminary experiments have pointed to the involvement of neuronal signals in regenerative growth and bone mineralization processes. Fish given a high Botulinum toxin dose had stagnated and significantly decreased fin regeneration compared to control fish administered sodium chloride. Fish given a low Botulinum toxin dose had normal fin growth, but significantly decreased bone mineralization activity. We hypothesize that this neurotoxin is preventing neuronal signals that promote fin regenerative growth as well as mineralization in regenerating bone tissue. Experiments are underway to develop standard procedures for amputation and Botulinum studies, and to better understand the mechanisms by which this occurs. Further experiments can be done to ensure that the neuronal pathway is the main contributor to bone regeneration or to develop ways to test other physical mechanisms that may also contribute. Provocatively, many organisms (including humans) possess the ability to regenerate limbs during embryonic stages; however, they lose this potential after birth. If the underlying mechanisms enabling fin regeneration can be discovered in Danio rerio, this will provide new strategies for regenerative medicine in humans.
- Presenter
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- Kai Jordan (Kai) Rogers, Senior, Microbiology Howard Hughes Scholar, Mary Gates Scholar
- Mentor
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- Ray Monnat, Genome Sciences
- Session
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- Commons East
- Easel #55
- 12:45 PM to 2:15 PM
Our goal is to use recently available large-scale genome sequencing data to build a comprehensive database of all known mutations in the Fanconi anemia (FA) genes, and then use these data to identify subsets of mutations that may be most susceptible to mutation-specific therapies. Fanconi anemia (FA) is a recessive disease caused by mutations in any one of 15 genes (FANC genes) that are part of a coordinated pathway that senses and repairs DNA damage. These mutations will serve as the focus for experimental work to determine how much FANC protein function is required to suppress the FA cellular phenotype, and which FANC mutations retain residual activity and may be better-suited for drug or small molecule therapeutics. This work was stimulated by the recent success of mutation-specific small molecule therapeutics in other recessive diseases such as cystic fibrosis. In complementary research we are using FA patient-derived cell lines to search for existing drugs and small molecules that suppress the FA cellular phenotype in response to aldehyde damage. Aldehyde damage is an unavoidable consequence of normal human physiology, and aldehydes are a common type of environmental mutagen and carcinogen. In contrast to our other research, this work is not focused on individual disease-causing mutations. We will present the screening assay being used for this part of the project, and preliminary results. We hope to identify FA disease-associated mutations that are the best candidates for future drug or small molecule research by virtue of retaining residual protein function, and thus the potential for rescue of function. We also hope to provide one example of a small molecule that can suppress the FA cellular phenotype regardless of the underlying mutation. Both results should aid the search for patient- and mutation-specific or more general therapies to prevent or treat Fanconi anemia.
- Presenter
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- Ariana Nakta (Ariana) Samadpour, Senior, Art (Painting and Drawing), Microbiology Mary Gates Scholar
- Mentor
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- Houra Merrikh, Microbiology
- Session
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- Commons East
- Easel #53
- 12:45 PM to 2:15 PM
DNA replication faces many obstacles as the genome is duplicated in all organisms. These obstacles include breaks in the DNA, tightly bound proteins as well as transcription. The encounters between replication and roadblocks can lead to replication stalling and genomic instability. To deal with replication conflicts, cells have mechanisms that act at regions of conflicts and help resolve them. Our lab is interested in these factors and in understanding how replication conflicts are dealt with in our model organism, Bacillus subtilis. Because Translesion Synthesis (TLS) polymerases are thought to act at certain stalled replication forks, in the context of DNA damage, we hypothesize that they play a more generalized role in resolving many different replication conflicts including those that are due to breaks. To determine if this is the case, we generated a deletion mutant of the yqjH gene. We have characterized this strain by specifically looking at its phenotypes under DNA damaging conditions. We are now looking to see if YqjH has any role in replication conflicts, both in terms of the severity of stalling and replisome stability, in B. subtilis.
- Presenter
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- Thivanka Kaushal Samaranayake, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Christine Luscombe, Materials Science & Engineering
- Session
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- MGH 241
- Easel #139
- 12:45 PM to 2:15 PM
In this study, we attempt to gain a better understanding of how poly(3-hexylthiophene) (P3HT) nanowires self assemble in solution. P3HT is used as the primary p-type donor in conjunction with phenyl-C61-butyric acid methyl ester (PCBM) in bulk heterojunction polymer solar cells. During self assembly, individual P3HT chains begin to kink after about 40 monomer units into an S-like shape. These S-shaped chains interact with one another via pi-pi interactions and form nanowires with widths typically between 20 and 70 nm and heights between 3 and 5 nm. In an attempt to improve device efficiency, we would like to exhibit greater control over the size of the nanowires. Controlling the morphology of the nanowires would allow us to improve the efficiency of the device. Thus, we demonstrate a method to create self-assembled nanowires from 12.5, 16, and 28 kDa molecular weight P3HT. P3HT solutions were made with a concentration of 1 mg of polymer to 2 mL of solvent (anisole and chloroform in a 4:1 ratio). These solutions were then heated at 80°C and thoroughly mixed for 16 h. After mixing, the solution is removed from heat and allowed to self-assemble for several days. Finally, the solution is then spin coated onto a silicon dioxide coated silica substrate. The samples were analyzed using atomic force microscopy to provide detailed information about the surface coverage, width, and height of the nanowires.
- Presenter
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- Krystal Slattery, Fifth Year, Biology (General), Earth & Space Sciences (Biology) NASA Space Grant Scholar, Undergraduate Research Conference Travel Awardee
- Mentors
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- Karen Junge, Applied Physics Laboratory, Applied Physics Laboratory
- Karen Cameron, Applied Physics Laboratory
- Session
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- MGH 241
- Easel #158
- 12:45 PM to 2:15 PM
The mechanisms that enable bacteria to be metabolically active at subzero temperatures are of considerable interest to studies of polar microbial ecology, astrobiology, climate and cryopreservation. The true nature of these mechanisms in marine bacteria remains elusive. Previously, protein synthesis within the sea ice bacterium Colwellia psychrerythraea str. 34H has been observed down to -20°C (and possibly lower) after being flash frozen with liquid nitrogen (Junge et al 2006). Here we report on the results of a long-term study of subzero metabolic activity, growth and protein expression of 34H cells not impeded by possible flash-freezing artifacts. 3H-Leucine- and Thymidine incorporation in addition to shotgun proteomics techniques were applied to 34H cultures incubated for up to 8 weeks at -1, -5, -10, -15, -20, and -196°C. Protein synthesis rates were found to be significantly higher without flash-freezing, in particular as temperatures dropped below -5°C. Furthermore, maximum protein synthesis and growth rates were observed at -1°C and -5°C. Evidence for growth cessation with continued protein synthesis at -10°C, and possibly below -10°C, were also obtained. Triplicate detailed proteomic profiling using tandem mass spectrometry are in progress and will help elucidate specific metabolic pathways that are selectively turned on or upregulated in order to facilitate the observed metabolic activities and growth at subzero temperatures. These combined efforts contribute to solving the critical puzzle concerning the establishment and maintenance of life in saline ice formations as well as provide valuable insight into low temperature cell physiology and adaptations for life in ice with significance to sea-ice ecology and seasonal transitions.
- Presenter
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- Denis Smirnov, Senior, Neuroscience, Biochemistry Amgen Scholar, Mary Gates Scholar
- Mentor
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- John Neumaier, Psychiatry & Behavioral Sciences
- Session
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- Commons West
- Easel #12
- 12:45 PM to 2:15 PM
A critical problem in the treatment of addiction is the tendency of addicted individuals to relapse to drugs-seeking with as many as 90% of addicts relapsing to use within one year. Exposure to stress is an important factor that precipitates relapse, though the exact mechanism is yet unknown. The Lateral Habenula (LHb) and the Rostromedial Tegmental Nucleus (RMTg), nuclei in the dorsal diencephalon, have recently become brain regions of interest in addiction research. Both regions have been shown to be important regulators of the midbrain dopaminergic systems, which are involved in relapse to cocaine seeking. However, very little is known about the precise role of these nuclei in stress-induced cocaine relapse. In our initial experiments, male, Long-Evans rats were handled for 3 days, and then injected with cocaine (10mg/kg) or exposed to intermittent footshock. Preliminary results demonstrate an increase in the expression of cFos, an early-detection transcription factor and marker for neuronal activity, in both the LHb and RMTg upon acute exposure to cocaine or foot shock. Studies are currently underway to determine the role of the LHb, and LHb projections to the RMTg on stress-induced cocaine reinstatement using the DREADD (Designer Receptors Exclusively Activated by Designer Drugs) technology in a rat self-administration reinstatement model.
- Presenter
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- Victoria Corin (Victoria) Smith, Senior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Holly Barker, Anthropology
- Session
-
- Commons West
- Easel #41
- 12:45 PM to 2:15 PM
I am interested in understanding how the impact of media portrayals on African American quarterbacks. I chose to look at the discourse used by sports analysts and spectators. Through social media and main stream sports news outlets, I began to gain an understanding of: how sports analysts and writers describe Black and White quarterbacks and how they differ? Hundley and Billings directly link this line of analysis in their article, "A Content Analysis of Racial Representations of NBA Athletes on Sports Illustrated Magazine Covers". Additionally, I looked at the research of Andrew Billings and Eugenio Mercurio in the differences of how White and Black players are characterized in terms of intelligence and athletic ability. I chose to use discourse, social media, and popular cultural analysis to answer my question. The importance and relevance of this work lies in the disproportionate perceptions created through hegemonic forces. The naturalization of these stereotypes discredits African American athletes’ achievement and may have residual effects on personal identity.
- Presenter
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- Ashley Nicole Celevante (Ashley) Soria, Senior, Chemistry
- Mentors
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- Carolyn Valdez, Chemistry
- James Mayer, Chemistry
- Session
-
- Balcony
- Easel #123
- 12:45 PM to 2:15 PM
Colloidal zinc oxide nanocrystals (NCs) become charged with electrons upon reduction with decamethylcobaltocene. Understanding this redox chemistry can further develop research on quantum dot sensitized solar cells and other various applications of NCs. The goal of my project is to determine whether this electron transfer can be characterized by an equilibrium constant Keq, and if so, to see which variables in the reaction affect the Keq. Two models were tested: (1) in which the concentration of NCs would affect the Keq, and another (2) in which it would not. Using data from optical titrations, I found that the Keq is affected by NC concentration and is therefore better described by model (1). Similarly, other variables are currently being tested in order to refine a working model that can accurately describe the reaction of NCs with reductants. The contribution of a simple model for these charge transfer processes can be applied to various areas.
- Presenter
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- Logan Warren Spencer, Senior, Oceanography
- Mentor
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- Miles Logsdon, Oceanography
- Session
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- MGH 241
- Easel #154
- 12:45 PM to 2:15 PM
Exploration of the geological structure of the seafloor is dependent upon acquiring accurate bathymetric data which includes representation of not only depth, but also a characterization of the acoustic backscatter due to absorption by the seafloor. Calibration of the Multibeam Echo Sounder system (MBES) used to acquire these data while the vessel experiences movement in heave, pitch, and roll, provides for accurate and comparative data between vessels and over time. This research investigates the use of the calibration methodology available with new post-processing sonar software prior to data acquisition. A patch test was conducted off the coast of Washington in early 2013 aboard the R/V Thomas G. Thompson using the Kongsberg EM302 multibeam sonar. The data obtained from this patch test were used as a case study. The new post-processing software is predicted to provide a more accurate bathymetric surface representation after the calibration method is performed. Results and recommendation from the calibration test are presented.
- Presenters
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- Christopher Michael (Chris) Stafford, Senior, Biology (Molecular, Cellular & Developmental)
- Kathleen Marie (Kathleen) Voss, Senior, Biology (Molecular, Cellular & Developmental)
- Mentor
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- Merrill Hille, Biology
- Session
-
- MGH 241
- Easel #163
- 12:45 PM to 2:15 PM
We are studying the roles of the p120-catenin protein in zebrafish development. p120-Catenin has a critical role in adhesion and migration by associating with E-cadherins and small, Rho family GTPases. The regulatory domain of p120-catenin contains 8 tyrosine and 8 serine or threonine residues that can be phosphorylated. To date, the function of these phosphorylation sites has been controversial. In cell cultures there is evidence that phosphorylation of 6 serine sites cause adhesions to recover quicker as well as form stronger connections. Some studies, however, claim that phosphorylation of these serine residues has no effect on adhesion. Tyrosine phosphorylation has been associated with nascent adhesions suggesting its role in adhesion formation, while its presence in carcinoma cell lines implies a role in cell motility. By selectively blocking phosphorylation at these 16 residues we hope determine the roles for the phosphorylation of serine and tyrosine residues in adhesion and migration of cells during embryogenesis. We mutated mouse p120-catenins at tyrosine residue 228 to phenylalanine, and at serine residues 252 and 268/288 to alanine via site-directed PCR mutagenesis. We inserted the DNA into PCS2+ vectors containing the fluorescent protein mcherry, and translated the mutant DNA into mRNA. We injected one-cell zebrafish embryos with an antisense morpholino RNA, complimentary to a splice-site region of endogenous zebrafish p120-catenin. Injections of this morpholino effectively knockdown the expression of newly translated p120-catenin mRNAs, and inhibit normal somite formation and axis extension during development. Co-injection of a wild-type mouse p120-catenin mRNA with the morpholino showed nearly normal development. Preliminary data suggests that co-injection of Y228F p120-catenin mRNA with the antisense morpholino RNA also produces nearly normal phenotypes. We will be testing the localization and function of the other mutated p120-catenins. This research could have important implications in development, treatment of some cancer types, and wound healing.
- Presenters
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- Kyle Forrest Staples, Senior, Materials Science & Engineering Mary Gates Scholar
- Kimbrelle Shey (Kimbrelle) Thommasson, Fifth Year, Materials Science & Engineering
- An H. Dang, Senior, Materials Science & Engineering
- Mentors
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- Fumio Ohuchi, Materials Science & Engineering
- Christopher Dandeneau, Materials Science & Engineering
- Session
-
- Balcony
- Easel #94
- 12:45 PM to 2:15 PM
For thermoelectric (TE) applications, oxides possess certain advantages over conventional intermetallics, including excellent high-temperature stability, low toxicity, and a complex structure, which aids in lowering the thermal conductivity. Recently, it has been found that SrxBa1-xNb2O6 (SBN) holds potential for use in high-temperature TE applications (e.g., waste heat recovery). In our work, a solution combustion synthesis (SCS) process was devised to fabricate SBN with a range of Sr:Ba ratios in order to ascertain an ideal SBN composition for optimum TE behavior. The SCS method, which is highly amenable to mass production, allowed for good control of the SBN stoichiometry, and the as-processed powders were found to possess good single phase purity. Powders processed with different SBN compositions were subject to conventional sintering followed by reduction. The TE properties of each SBN composition were then tested and compared. Preliminary results of our acquired data suggest a decrease in the thermal conductivity as the Ba content is increased, likely due to the larger mass of Ba when compared to Sr. From the obtained results, an ideal SBN composition was determined having the optimal TE performance. Field assisted sintering (FAST) was then employed to processed SBN powder having the optimum composition, and the TE properties of the SBN from both conventional sintering and FAST were compared.
- Presenter
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- Nicholas K (Nic) Stender, Senior, Bioen: Nanoscience & Molecular Engr
- Mentors
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- Daniel Ratner, Bioengineering
- James Kirk, Bioengineering
- Session
-
- Commons East
- Easel #47
- 12:45 PM to 2:15 PM
Silicon microring resonator biosensors utilize nanoscale light confinement to detect biomolecules in a real-time and label-free manner with high sensitivity. Detecting the presence of antibodies that bind human tissue and blood antigens is crucial in transplant and transfusion medicine, as mismatched products can impact the clinical outcome of the recipient. The focus of the current research is to improve data analysis methods to perform serologic analysis of human plasma using a silicon photonic chip. Microring resonator chips were prepared by physisorption of streptavidin followed by functionalization with biotin-conjugated histo-blood group antigens. Testing was performed using undiluted human plasma to detect histo-blood group antibodies on the functionalized chip surface. A secondary enhancement step using an anti-immunoglobulin antibody enabled the quantification of the surface bound antibodies. Data analysis was performed using on-chip positive and negative controls, and kinetic analysis was accomplished using association models. The quantitative determination of antibody binding profiles with a model antibody system is discussed to show how these devices can ascertain kinetic behavior. Positive determination of plasma antibody content is shown, proving these devices can be used in this application at current clinical standards. These devices are suited for clinical translation and with proper quantitative models and testing they could surpass current clinical methods.
- Presenter
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- Clinton William (Clinton) Stipek, Senior, Oceanography
- Mentor
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- Miles Logsdon, Oceanography
- Session
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- MGH 241
- Easel #155
- 12:45 PM to 2:15 PM
With sea level projected to rise by as much as 2 meters by 2100, understanding historical sea level rise is imperative. This increase in sea level has the potential to displace up to 187 million people globally. Damages will exceed into the billions of dollars and the safety of coastal communities will be at great risk. Improved knowledge of historic sea level rise will significantly help reduce these potential losses. This project reconstructed sea level rise along the continental shelf since the last glacial maximum. Multibeam echo sounder (MBES) was used along with a subbottom profiler to reconstruct a continental shelf boundary adjacent to the coast. Transect lines were composed parallel to each other from 90 to 120 meters using MBES and a subbottom profiler to acquire measurements of the seafloor. These remotely sensed estimates of depth have provided evidence of a lowstand level as well as historic shorelines since the last glacial maximum. As sea levels continue to rise, understanding the history is vital to making a long term forecast for the future. Having this information will provide some insight into the extent and durability of shoreline building processes that must take place.
- Presenter
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- Hyong Won (Danny) Suh, Senior, Biochemistry, Applied & Computational Mathematical Sciences (Biological & Life Sciences)
- Mentors
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- Shao-En Ong, Pharmacology
- Ho-Tak Lau, Pharmacology
- Session
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- Commons East
- Easel #58
- 12:45 PM to 2:15 PM
Quantitative mass spectrometry (MS)-based proteomics is a powerful approach to measure relative expression changes across thousands of proteins in a complex mixture. Commonly, stable isotopes like 13C and 15N are incorporated into proteins and peptides by metabolic labeling (ML) or chemical labeling (CL) to produce “heavy” labeled forms. Mixtures of light and heavy peptides can be identified and quantified by MS. In ML, proteins are labeled in vivo by growing cells with isotope labeled metabolic precursors, while peptides are chemically labeled in vitro in CL. These two labeling approaches have distinct workflows and their own strengths and limitations. In a typical proteomics experiment, complex mixtures of peptides are separated on reversed phase liquid chromatography (LC) and sampled in real-time by the mass spectrometer for peptide identification and quantification. We propose to analyze mixtures of chemically and metabolically labeled peptides in single LC-MS runs, comparing each method’s quantitative accuracy and precision, and other factors, such as analytical losses from sample processing without errors introduced by stochastic sampling. We compare stable isotope labeling by amino acids in cell culture (SILAC) and reductive dimethylation CL by mixing equal amounts of peptides from each approach.Preliminary results indicate minimal differences between ML and CL in quantifying proteins (median of >2 peptide ratios). With individual peptides, however, CL showed 13% larger variance than the ML. We observed signal losses in CL samples compared to ML samples, and fewer quantified peptides and proteins in CL (6005 peptides, 897 proteins) than in ML (7448 peptides, 1059 proteins). We attribute the differences to the extra labeling step in CL, and will perform further analyses with ratio mixtures of heavy and light labeled peptides to clarify the source of variance. Our comparison of CL and ML will guide future optimization and applications of both quantitative proteomics labeling methods.
- Presenter
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- Kristina Kaylynn (Kristina) Sumner, Senior, Earth & Space Sciences (Physics)
- Mentors
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- Katharine Huntington, Earth & Space Sciences
- Karl Lang, Earth & Space Sciences
- Session
-
- Balcony
- Easel #101
- 12:45 PM to 2:15 PM
Current research in Himalayan geodynamics focuses on the complex relationship between surface erosion and active rock uplift. This study focuses on the Eastern Himalayas, where the Yarlung-Tsangpo River abruptly turns southward, incising over a 2 km deep gorge through the easternmost Himalayan mountains to join the Brahmaputra River in Assam. Because geologists have primarily concentrated on just the surface geology, they have struggled to explain this massive gorge despite over a decade of research. Our research takes a new approach to this aging problem by examining the sedimentary record immediately downstream of this gorge. In fact, sedimentary rocks of the eastern Siwalik foothills preserve the full record of Himalayan uplift as well as the evolution of the river systems draining the Tibetan Plateau. Here we focus our research, interpreting the sedimentary record through both detrital zircon U-Pb dating, which is a radiometric dating technique, and modal analysis, which is an evaluation of the minerals present within the samples from these Siwalik units. Past research results suggested a stable sedimentary provenance sourcing from both Himalayan and Tibetan source rocks, but new higher resolution modal analysis will add valuable insight into the competitive influences of progressive roofing of the high Himalayas and sediment recycling in the Himalayan foreland. Furthermore, this research provides valuable new data for a region of the Himalayas where there is currently a deficiency of information from the sedimentary record. This information is necessary for a full comparison of landscape evolution westward across the great Himalayan arc, and also shows a regional relationship between climate and tectonics.
- Presenter
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- Soo Nee (SooNee) Tan, Junior, Biochemistry
- Mentors
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- Julia Staverosky, Chemistry, Global Health
- Pradipsinh Rathod, Chemistry
- Session
-
- Balcony
- Easel #120
- 12:45 PM to 2:15 PM
Malaria is a parasitic infection due to Protozoa Plasmodium. This is a severe global disease with 250 million annual cases leading to 1-2 million deaths. The most virulent, P. falciparum, is responsible for severe clinical malaria and death. An array of anti-malarial treatments exist today, however parasites evolve continuously to develop resistance even to the newest frontline anti-malarial drugs. Previous studies in the Rathod laboratory have demonstrated that drug resistance can be generated in the lab and that some drugs can be utilized to characterize Accelerated Resistance to Multiple Drugs (ARMD) parasites, such as the laboratory strain Dd2, and non-ARMD parasites, such as the laboratory strain HB3. In the current study, we are using a cyclopropyl carboxamide (GSK 2645947) to select for resistant parasites. Cyclopropyl carboxamides are a chemically novel class of antimalarial agents identified recently and they prevent the growth of P. falciparum in the early trophozoite stages of the erythrocytic Plasmodium cycle. This project focuses on determining the conditions for the development of resistance against GSK 2645947 with Dd2 and HB3 by conducting a series of selection experiments utilizing different concentrations of GSK 2645947 and starting parasites populations. Unlike previous conditions which indicate that the Dd2 strain acquires resistance at a significantly higher frequency than the HB3 stain; the data from this study suggests that both Dd2 and HB3 strains respond similarly to GSK 2645947. Through this study, we can further understand the behavior of resistant P. falciparum parasites.
- Presenter
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- Kendrick Chu (Kendrick) Tang, Senior, Electrical Engineering, Mathematics Amgen Scholar
- Mentors
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- Eric Shea-Brown, Applied Mathematics
- Yu Hu, Applied Mathematics
- Session
-
- Commons East
- Easel #71
- 12:45 PM to 2:15 PM
Understanding the heterogeneity in neural activity will help develop theories in neural dynamics and coding - how sensory information is encoded via spike times and patterns. For example, the correlation structure of spiking activity in neural populations, which affects the collective coding capacity, is heavily dependent on the heterogeneous distribution of firing rates across neural networks. A natural cause of heterogeneity in a network arises from the non-regular connectivity between neurons. To capture this natural heterogeneity, we used an adapted Erdos-Renyi node-probability model to construct random architectures for both purely excitatory and excitatory-inhibitory networks of different sizes. The Erdos-Renyi model flips a weighted coin defined by a probability parameter to determine whether a path between nodes exists. However, we need to construct directed graphs, so we adapted the Erdos-Renyi model to construct directed paths based on the probability parameter. For each randomly generated network we examined the coherent structure of the steady-states that persist as the connection strengths between neurons are uniformly increased. In purely excitatory networks, we saw that the steady-state growth is very linear with respect to the connection strength of the network. As a result, stronger connection strengths lead to stronger heterogeneity between the firing rates within the network. We are using the coefficients in the linear approximations to steady-state growth to define the coherent structure of each network. We are continuing towards finding a relationship between the frequencies of three-cell connectivity motifs and this coherent structure since realistic neural network connectivity patterns are not purely random, but have significantly prevalent motifs that define neural architecture. We are specifically looking at how different frequencies of chain, divergent and convergent three-cell motifs affect the first and second order moments of the coherent structure that represents the heterogeneity.
- Presenter
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- Jessica Ann (Jessica) Tjalsma, Senior, Materials Science & Engineering, Physics: Comprehensive Physics
- Mentors
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- Marjorie Olmstead, Physics
- Fumio Ohuchi, Materials Science & Engineering
- Session
-
- Balcony
- Easel #110
- 12:45 PM to 2:15 PM
β-Ga2O3 is a transparent conducting oxide that is well suited to ultraviolet (UV) photovoltaics. One application possibility is as a UV energy harvesting device in space, where UV light is much more abundant than solar. Because of the anisotropy of β-Ga2O3, spectroscopic measurements for a full range of polarization with respect to angles of orientation were taken to obtain optical constants. These measurements were made for both single crystal and thin film samples. As expected, the optical constants vary depending on both the sample type and the orientation of the sample. From these data a model was built that is able to identify the orientation of the single crystal samples. The next step is to build a model that will be used to determine thin film thickness of β-Ga2O3 deposited by our group on different known substrates.
- Presenter
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- Ariel Mei (Ariel) Townsend, Junior, Oceanography
- Mentors
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- Julian Sachs, Oceanography
- Daniel Nelson, Oceanography
- Session
-
- Balcony
- Easel #124
- 12:45 PM to 2:15 PM
This project seeks to better understand climate change corollary to the migration of the Intertropical Convergence Zone (ITCZ) in the tropical Pacific from the Little Ice Age (~AD 1400-1850) to the present using hydrogen isotopes as a proxy for climate change. During this time, the ITCZ is hypothesized to have reached its most southern location, the consequences of which were evident on a global scale. However, more research is needed to further investigate this hypothesis. Specifically, this study examines hydrogen isotope ratios of the source specific lipids Taraxerol and Dinosterol from Lake Escondido, Isabela Island, Galapagos. Lipids were solvent-extracted from sections of the cores, separated through silica gel columns, and the ratio of Deuterium and Hydrogen (δD) of specific lipids was quantified using a Gas Chromatograph-Isotope Ratio Mass Spectrometer. The combined fluxes of both terrestrially and aquatically sourced δD ratios over time provide a proxy for climate change through the present. Due to the widespread effects of the ITCZ on global hydrology, understanding its movement, and what triggers migration, can provide insight into future climate scenarios.
- Presenter
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- Amanda Anh Ngoc Nhat (Amanda) Tran, Senior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Holly Barker, Anthropology
- Session
-
- Commons West
- Easel #40
- 12:45 PM to 2:15 PM
I am interested in examining the importance and values that super sports fans hold towards their favorite teams through the cultural and linguistic norms that are created and reproduced through social media outlets. Cultural and linguistic norms are the commonalities found within the actions, behaviors, and language tendencies of a particular group of people. For the purpose of this research, I will be looking specifically at the Seattle Seahawks “12th Man,” a group of football fanatics that consider themselves to be the Seahawks’ most loyal supporters. Fan cultures can be difficult to understand if you are not part of one, and are often devalued. Research done by Harrington Lee and presented in the article "A Life Course Perspective on Fandom,” discusses the concepts of fandom and how these identities evolve throughout the course of one’s life and are influenced by many factors (i.e. family, location, media, etc.). Social media outlets such as online forums, blogs, internet memes, Facebook, and Twitter have become a large part of the super sports fan communities and how they interact and communicate with each other, as well as how they are perceived by outsiders. While using these social media outlets as my main method of research, I will also be utilizing photovoice (analyzing photographs that portray the community and have symbolic meaning) and discourse analysis (words and language used in media that shape identity). This research is meaningful because sports fans around the world hold a great amount of passion, dedication, pride, and emotional attachment to their teams, and the influence this has made among their identities and cultures outside of sports is essential to note. The super fan culture is important to every “12th Man” and it will be interesting to see how social media continues to perpetuate these norms within the community.
- Presenter
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- Judy R (Judy) Twedt, Fifth Year, Physics: Comprehensive Physics Mary Gates Scholar, NASA Space Grant Scholar
- Mentor
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- Dargan Frierson, Atmospheric Sciences
- Session
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- MGH 241
- Easel #143
- 12:45 PM to 2:15 PM
The rate at which the ocean absorbs heat from the atmosphere is poorly understood in the climate system, and is a large source of uncertainty in predictions of climate change. Furthermore, the spatial distribution of ocean heat uptake is tightly coupled to major patterns in global ocean circulation. Changes in the distribution of ocean heat uptake may have long term repercussions on global climate patterns. Using global climate model output from the Coupled Model Intercomparison Project (CMIP5), this study examines: A) model predictions of ocean heat uptake over time, and B) the relationship between heat uptake, surface wind stress, and eddy parameterizations in the Southern Ocean. All calculations were averaged over three 20 year periods spanning 1860 - 2100 under a scenario of increased greenhouse gas emissions. For each time period and each model, the ocean heat uptake was averaged across bands of constant latitude. We found that although all the models show hemispheric asymmetry in ocean heat uptake, they vary widely in projections of how the asymmetry changes over time. To isolate a potential cause of this asymmetry, we use Ekman theory to examine upwelling induced by surface wind stress in the Southern Ocean. We anticipate a positive correlation between surface winds and ocean heat uptake, although this is relationship is complicated by the depth of the mixed layer, and the various methods of representing ocean eddies.
- Presenter
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- George T (George) Ueda, Senior, Biochemistry, Biology (General)
- Mentor
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- Sakeneh Zraika, Medicine, VA Puget Sound Health Care System
- Session
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- Commons East
- Easel #70
- 12:45 PM to 2:15 PM
Neprilysin (NEP) is a plasma membrane metalloendopeptidase expressed in pancreatic islet β cells. In non-islet tissues, it has been shown to modulate ion flux. Whether NEP modulates potassium and/or calcium flux in β cells that are necessary for glucose-stimulated insulin secretion (GSIS) is unknown. Thus, the purpose of this study was to determine whether NEP acutely regulates GSIS and if so, where NEP acts in the secretion pathway. To do this, islets were isolated from 8-10 week old C57BL/6 mice. Following overnight recovery, islets were pre-incubated for 30 minutes in 2.8 mM glucose and then stimulated for 60 minutes with either 2.8 mM (basal) or 20 mM (stimulated) glucose in the absence or presence of the NEP inhibitor thiorphan (50 uM). To measure the effects of NEP inhibition on GSIS mediated by Ca2+ channel activity independent of K+ATP channel-induced depolarization, in some conditions a Ca2+ channel agonist (BayK-8644, 1 uM) was used in combination with a K+ATP channel opener (diazoxide, 500 uM). The results showed that acute inhibition of NEP significantly reduced 20 mM glucose-stimulated insulin secretion (128.1±16.0 vs. 80.5±11.4 pM/5 islets; n=11, p=0.03) without affecting basal insulin secretion (13.9±3.8 vs. 8.7±2.3 pM/5 islets; n=11, p=0.26). In addition, NEP inhibition did not alter insulin secretion in response to BayK-8644 plus diazoxide (33.0±6.1 vs. 38.2±8.1 pM/5 islets; n=6, p=0.62), suggesting NEP may be acting to modulate GSIS at a step that is proximal to the Ca2+ channel. It can be extrapolated from this data that NEP may play an important role in the insulin-secretion pathway and thus, acutely upregulating NEP may prove effective in treating type 2 diabetes.
- Presenter
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- Mariah Eryn Vane, Senior, Environmental Studies
- Mentor
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- P. Sean McDonald, Program on the Environment
- Session
-
- Commons West
- Easel #37
- 12:45 PM to 2:15 PM
Public parklands provide a space for recreation and ecosystem protection. However, managing parks for these traits can be a challenge as the two activities are often in conflict. The aim of this study is to explore the trade-offs between ecosystem protection and recreation in public parks through a case study of Fay Bainbridge Park (FBP) on Bainbridge Island, Washington. Bainbridge Island Metro Park & Recreation District (BIMPRD) with guidance from Washington Sea Grant (WSG) proposed the addition of three boardwalks at FBP with the intention of providing beach access and reducing trampling. For this study, I worked with WSG and BIMPRD to survey park visitors. The survey focused on participants’ use of FBP, their current understanding of the local ecosystem, and their feelings toward the addition of beach boardwalks, specifically impacts of boardwalks on beach ecology, aesthetics, and accessibility. In order to place this study in the context of public park management, I conducted a literature review of related case studies. The survey results revealed patterns concerning park use, prior ecological knowledge, and feelings toward the addition of boardwalks at FBP. This study will help inform BIMPRD and WSG on infrastructure decisions and the development of educational signage. More broadly, this work contributes to the larger body of information concerning appropriate public parkland management that maximizes value to visitors without compromising the health of park ecosystems.
- Presenter
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- Breanna Lee (Breanna) Walker, Sophomore, Aquatic & Fishery Sciences Mary Gates Scholar
- Mentor
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- Kristin Laidre, Applied Physics Laboratory
- Session
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- MGH 241
- Easel #169
- 12:45 PM to 2:15 PM
The Salish Sea is critical habitat for the endangered population of Southern Resident Killer Whales (SRKW). One of the primary threats to SRKW recovery is underwater noise pollution from boat and ship traffic. Killer whales rely on acoustics to communicate, navigate, and to forage in their underwater environment. The increasing levels of underwater noise have the potential to mask the SRKW calls and echolocation clicks, resulting in compensation (i.e. increasing the loudness of calls and using echolocation more or less frequently). This study investigates the potential effects that boat and ship traffic may have on SRKW echolocation. If SRKWs are experiencing masking while actively using echolocation, it is expected that there will be a significant difference between echolocation click rates in a quiet underwater environment and click rates produced in an underwater environment filled with noise pollution. Passive acoustic monitoring was used to record SRKW acoustics and measure the received levels (RL) of underwater noise. Visual boat and ship counts were conducted during acoustic recordings to quantify the amount of traffic in the study area (Whale Watch State Park, San Juan Island, WA). These data sets are being tested to determine if there is a significant correlation between the RL of underwater sound and boat and ship traffic, and if echolocation click rates change in respect to the RL of underwater sound. The anticipated results are that boat and ship traffic will be directly connected to the increases in RL of underwater sound and that masking will be impacting SRKW use of echolocation. Southern Resident Killer Whale population recovery is faced with a number of threats, however underwater noise pollution is one that we, as a society, can directly impact. Consequently, it's extremely important for us to understand how underwater noise pollution can affect this endangered population of killer whales.
- Presenter
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- Takato Watanabe, Senior, Anthropology
- Mentor
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- Holly Barker, Anthropology
- Session
-
- Commons West
- Easel #39
- 12:45 PM to 2:15 PM
The media impacts sports in many ways by reporting stories as a way to distract an athlete. There are many stories in the sports industry where the media attacks an athlete and their personal life through outlandish stories. Some examples of this are how many athletes are targeted through their girlfriends. Manti Te’o and his hoax girlfriend, AJ McCarron’s girlfriend during the BCS national title game, Tiger Woods’ affair and Hope Solo and Jeramy Steven’s domestic abuse are some stories that the media has focused much of their attention on. Most importantly, how does the media shape cultural norms about significant others of athletes? I will be looking at popular culture and media to analyze what impact media has on an athlete’s relationship. From my personal experience I believe that the media propagates stories exponentially out of proportion. To challenge my hypothesis I will use the methods of photo voice, interview and discourse analysis of pop culture. An article written by Paul Husselbee and Kevin Stein shows an analysis of Tiger Woods’ scandal breaking down what exactly happened during his affair. This article focused on what was going on during trials and the aftermath. ESPN and other sports broadcasting companies made his affair a worldwide issue. Most media articles are written to get more people to tune into the story rather than laying out the complete truth. This research is important because people follow media and believe everything that is being broadcasted without looking at the fine print and details. I believe I will find that the media has a significant impact on fans when they view athletes. If more people realize there is more to a story than what is being shown, then stories would not be so extreme.
- Presenter
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- Ceri Joanna (Ceri) Weber, Senior, Biology (Molecular, Cellular & Developmental)
- Mentors
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- Michelangelo von Dassow, Friday Harbor Laboratories, Duke University
- Billie J. Swalla, Friday Harbor Laboratories
- Session
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- MGH 241
- Easel #157
- 12:45 PM to 2:15 PM
Organisms can develop normally and thrive in dynamic environments. The interplay between the environment and the biomechanics of morphogenesis can help us understand how development operates in a changing world. Effects of salinity on blastula expansion in the sand dollar Dendraster excentricus were used to investigate interactions among the environment, development, and mechanics. Salinity fluctuations, which are common in Dendraster's habitat, affect embryonic cell size. The hyaline layer, an extracellular matrix layer closely associated with the outside of the blastula, is hypothesized to resist blastula expansion. Four models describing how the hyaline layer responds to blastula expansion were compared. In three models the hyaline resists expansion as either an elastic, plastic, or viscous layer. In these models, salinity-driven changes in cell size were predicted to cause changes in the ratio of blastocoel volume to cell volume. In a fourth model, the hyaline is a perfectly accommodating layer that allows the embryo to expand freely as cells divide in a single layer. In this model, salinity changes were predicted not to affect the blastocoel-to-cell-volume ratio. To test these hypotheses, Dendraster embryos were placed in either 25‰ or 32‰ seawater wells and switched to wells of either the same or the other salinity. In a second experiment, Dendraster embryos were raised in 32‰ seawater until the 16-cell stage, at which point a subset of embryos were moved to 25‰ seawater for one cleavage stage and then moved back to 32‰ for the duration of the experiment. In both experiments blastocoel-to-cell-volume ratios were not affected by the salinity treatment. These results suggest that the hyaline layer does not resist blastula expansion in Dendraster, thereby maintaining a constant blastocoel-to-cell-volume ratio.
- Presenters
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- Alexander (Alex) West, Sophomore, Biology, Computer Science, North Seattle College
- Debra Del Castillo, Fifth Year, Biochemistry, North Seattle College
- Joanna Qiao Zuo Liew, Senior,
- Zeno DeRooy, Sophomore, Chemistry, North Seattle College
- Richard Won (Richard) Lee, Junior, Extended Pre-Major
- Jennifer Elliott
- Mentors
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- James Patterson, Chemistry, North Seattle Community College
- Brian Saunders, Biology, North Seattle Community College
- Session
-
- Balcony
- Easel #115
- 12:45 PM to 2:15 PM
Two strains of Botryococcus braunii algae were grown in three different sets of conditions to compare growth characteristics and lipid production. One species, UTEX LB 572, was a Race A Botryococcus braunii from the culture collection of the University of Texas in Austin. The second species, AC 762, was a Race B Botryococcus braunii from the culture collection of the University of Caen, France. UTEX 572 was found to produce two hydrocarbon chain lengths of C:16 and C:18 in a 2:3 ratio respectively. The AC 762 was found to produce hydrocarbons called botryococcenes of chain lengths between C:30 and C:36. The lipid chain lengths of both strains were evaluated by mass spectrometry. The UTEX 572 lipid content was quantified by analytical spectrometry after direct transesterification of the lipid content to biodiesel. The AC 762 lipid content was quantified by a photospectrometry technique developed by UC Berkeley researchers Eroglu and Melis (1985). Cells of both species were harvested during exponential growth phase from 400 mL of growth media and then freeze dried and analyzed gravimetrically. Nine flasks of each species were grown with 3000 lux average light intensity on a 12h:12h light:dark cycle at room temperature averaging 22° C. Three flasks of each species were grown with 1.5% CO2 in BG-11 media, three flasks of each species were grown in BG-11 media with air only and three control flasks were grown in respective carrier medias as those used in the algae collection of origin. Knowledge of the rates at which AC 762 and UTEX 572 produce hydrocarbons as well as the specific lengths and proportions of those hydrocarbons contributes to data needed for comparison of economic considerations in industrial applications.
- Presenters
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- Jennifer Mackenzie (Jennifer) Whitehead, Senior, Biology (General)
- Matthew Eugene Pouw, Senior, Microbiology Mary Gates Scholar
- Natalie Chen, Senior, Biology (Molecular, Cellular & Developmental)
- Mentor
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- James Mullins, Microbiology
- Session
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- Commons East
- Easel #57
- 12:45 PM to 2:15 PM
To be infected with human immunodeficiency virus (HIV) is to face a lifelong battle. Even with the combined force of multiple antiretroviral drugs to target different phases of the HIV life cycle, one cannot eliminate human immunodeficiency virus (HIV) from the body. This is due to persistence of virus reservoirs, compartments, or sanctuaries. Reservoirs are tissue sites characterized by collection of virus over time: viral populations show low divergence from the founder virus and high diversity between each other. Compartments are tissues with limited gene flow: they are pockets of virus with limited entry and exit. Sanctuaries are tissues that resist penetration of antiretroviral drugs: they can set up the conditions for reservoirs or compartments. To understand how and where these sites of persistent infection endure in the body even during antiretroviral therapy (ART), we are conducting a systematic characterization of possible sites in the infected host. We are studying viral populations present in biopsy-derived gut-associated lymphoid tissues (GALT) and other autopsy-derived tissues of patients who died while on antiretroviral therapy (ART). Viral populations are sampled from tissues using molecular lab techniques (including polymerase chain reaction and Sanger sequencing) and analyzed using phylogenetic trees and computational programs that measure diversity, divergence, and clustering. Our study addresses two main aims: (1) to find the tissue sites in the host critical in maintaining latent HIV infection during suppressive ART and (2) to find tissue sites critical in supporting continued viral replication and the emergence of pathogenic phenotypes during ART by characterizing sites as reservoirs, compartments, or drug sanctuaries. Hopefully our research will help to direct future methods of HIV treatment by allowing researchers and clinicians to better understand how and where virus persists in the body.
- Presenter
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- Curtis Liam (Curtis) Whittle, Senior, Chemical Engr: Nanosci & Molecular Engr
- Mentors
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- Lilo Pozzo, Chemical Engineering
- Jeffrey Richards, Chemical Engineering
- Session
-
- Balcony
- Easel #113
- 12:45 PM to 2:15 PM
Poly(3-hexylthiophene) (P3HT) and 6,6-phenyl-C60 butyric acid methyl ester (PCBM) are model materials used to study and understand the performance of polymer solar cells. A critical design parameter in improving device performance is the structural morphology of the active layer. Traditional processing of organic solar cells involves the deposition of a P3HT/PCBM composite film from a common solvent and then post-processing treatments (i.e. annealing) to influence the extent of phase segregation and improve the percolation of electron and hole transport pathways throughout the film volume. Therefore, the electronic properties of the resulting solar cells are inherently tied to how the film is processed (e.g. choice of solvent, annealing temperature, film thickness). While process optimization has led to improvements in laboratory performance, it is challenging to extend the same principles to improve the performance of large scale roll-to-roll processes because deposition conditions vary significantly. Increasingly, researchers recognize the need for methods that decouple film processing from active layer structure and device performance. My research involves the synthesis of P3HT/PCBM composite nanoparticles (CNPs) in aqueous dispersion as a means to circumvent the dependence of active layer structure on the specific mode of deposition of the P3HT/PCBM film. I have synthesized CNPs with variable content of P3HT/PCBM and different preparation procedures while also controlling particle size. The characterization of these particles focuses on spectroscopy, small angle X-ray scattering (SAXS), dynamic light scattering and the performance evaluation of devices produced with CNP active layers. This project will tie device performance to CNP structure regardless of active layer processing, and assist in identifying CNPs with optimized morphology without the need for annealing or post-processing.
- Presenters
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- Nevan Wichers, Freshman, Computer Science, Edmonds Community College
- Nasir Elmi
- Spencer Roberts
- Mentor
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- Tom Fleming, Physics, Edmonds College
- Session
-
- Balcony
- Easel #95
- 12:45 PM to 2:15 PM
The field of Brain Computer Interface (BCI) systems is concerned with the study of how thoughts alone can be used to interface with and control the actions of external systems. Such BCI systems have been actively studied since 1969 when the seminal work of Fitz, et. al. at the University of Washington showed that monkeys could voluntarily control the deflection of an external meter with their thoughts alone. To date, there has been extensive research in this area as concerns thought-control of external devices in focused-activity environments, such as video gaming, but research into the effectiveness of BCI methods in more-realistic, distracted-environments is somewhat sparse, with notable exceptions including the work of Lalor, et. al., who performed a non-controlled and non-randomized study of the effects of Steady-State Visual Evoked Potentials (SSVEP) on real-time video-gaming control and Friedricha, et. al. who performed a study on the effects of auditory distractions on the accuracy of BCIs. Our present study represents a refinement of the Lalor approach in a broader scope than video-game control through the addition of more carefully defined controls, and we further extend this research through the study of the effects of simultaneous auditory and visual environmental conditioning. Based on the study of Friedricha, et. al. involving auditory distractions, we expect a constant auditory tone to have no impact on BCI performance.
- Presenter
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- Lindsay Rebecca (Lindsay) Wilson, Senior, Speech and Hearing Sci (Com Disorders), Early Childhood & Family Studies
- Mentor
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- Sarah Roseberry, Speech & Hearing Sciences
- Session
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- Commons West
- Easel #14
- 12:45 PM to 2:15 PM
Triadic eye gaze, a form of coordinated attention, is defined as an infants’ eye gaze shifts between another person, and an outside object or person. The current study examined whether 9-month-olds’ triadic eye gaze influences language learning; we specifically asked whether infants who engage in more episodes of triadic eye gaze show increased phoneme learning in a foreign language. The current project was conducted as part of a larger research endeavor, the Interactive Exposure study, which examined infant language learning in the context of peer social interactions. In the Interactive Exposure study, infants were exposed to a foreign language, Mandarin Chinese, through individual and peer language exposure sessions. In 12 sessions over four weeks the infants watched video clips of Mandarin Chinese. Infants activated the 20-second video clips by touching the screen. Infants in individual exposure sessions were in the room with only the touchscreen and their caregiver whereas peer exposure sessions consisted of two infants and two caregivers. Following exposure, infants’ discrimination of the Mandarin Chinese phonemes was tested via Conditioned Head Turn procedure and an ERP task. Fifteen 9-month-old participants from the peer language exposure sessions were selected for the current analysis of triadic eye gaze patterns. Using ELAN coding software, infants’ eye gaze was coded for looks to their own caregiver, other caregiver, other infant, and screen. Next, episodes of triadic eye gaze were identified for eye gaze patterns that consisted of looks between the other infant, caregiver, other caregiver and screen (e,g,, other infant – TV – other infant). Although coding and analysis are currently underway, we predict that infants who engage in more episodes of triadic eye gaze will show increased phoneme learning. If our prediction is accurate, this finding will indicate that language learning requires complex social interactions, such as triadic patterns of attention.
- Presenter
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- Margaret Morrison (Meg) Wilson, Sophomore, Earth and Space Sciences: Geology
- Mentors
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- Sarah Loebman, Astronomy
- Ana Larson, Astronomy
- Session
-
- Balcony
- Easel #103
- 12:45 PM to 2:15 PM
We present an extension of the Astronomy Department’s curriculum for visually impaired junior high school students. Our lesson plans are a complementary addition to Noreen Grice's Braille and large print readings. These lessons satisfy the Washington State Essential Academic Learning Requirements (EALR's) for junior high school students, the level at which students are introduced to astronomy. We present here a sample of new material that covers the composition, formation and evolution of the Sun. Our lessons include activities, audio tracks, 3D models, and online links to advanced topics. We outline additional curricula that we are actively developing, such as biographies of visually impaired astronomers and topics including the formation and evolution of the Solar System's terrestrial planets. We will test our curricula during this coming school year, as we did in 2007, at the Washington State School for the Blind, with the expectation of deeply strengthening the students' understanding of the evolution of the Sun beyond what is available in their textbooks. Ultimately, this curricula will be distributed and utilized throughout the United States as part of the on-going national and international efforts to promote astronomy for those who are visually impaired. We conclude with a description of our role in building and testing additional educational tools.
- Presenter
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- Janice Bernadette (JJ) Wood, Senior, Anthropology, Earth & Space Sciences
- Mentor
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- Patrick O'Grady, Anthropology, University of Oregon
- Session
-
- Balcony
- Easel #109
- 12:45 PM to 2:15 PM
Archaeological excavations at the Rimrock Draw Rockshelter site (35HA3855), located in southeastern Oregon, revealed a three-part stratigraphic series of eolian deposits underlain by silty clays, and orange sandy clay sediments. These are found in nearly all excavated units of the rockshelter. Excavation units contained Western Stemmed points that date between 8,000 to 12,000 years in age, frequently in sediments that lack a uniform stratigraphy due to post-depositional alteration and sediment mixing from burrowing animals. However; Unit 11 is the exception, revealing a thick tephra lens underlain by distinct layers of banded black and gray prismatic clay, then by bone fragments of a large mammal that may be megafauna. These features mark a significant change in stratigraphic clarity, offering researchers the most clearly defined stratified deposits in the site thus far. The goal of this research is to establish a stratigraphic framework using geoarchaeological methods including particle size analysis for grain size distributions; geochemical analysis of collected sediment samples to test soil pH levels; electrical conductivity; and organic loss on ignition to determine the nature of the paleoenvironment. Also, this project offers an interdisciplinary collaboration to chronologically date this unique sequence of deposits using electron microprobe analysis on two collected tephra samples, and radiometric dating on bone fragments found near the bottom of the Unit 11. I expect the results of these methods to show strong andic-type soil properties, give a statistically meaningful stratigraphic division of depositional units, and provide several chronological dates to be used as marker horizons. Together, these results will demonstrate the strong associative context between excavated archaeological material and the stratigraphic record.
- Presenter
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- Shauna Anne Woolley, Senior, Anthropology: Medical Anth & Global Hlth
- Mentor
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- Holly Barker, Anthropology
- Session
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- Commons West
- Easel #38
- 12:45 PM to 2:15 PM
I am interested in how new developments and understandings of degenerative brain disease in football players have influenced discourse and policy surrounding risk. A recent explosion of information regarding the long-term dangers of cranial trauma in contact sports has flooded the public conscience. The question I want to address is: has this new information impacted the way that risk is discussed and understood among football players, coaches, and fans? I will look at a combination of print and social media, conduct interviews, and use discourse, positionality, and archival research methods to understand the issue. Through these methods I hope to find that new developments and understandings of degenerative brain disease have cultivated discussion and promoted more stringent testing and policy towards cranial trauma in football players. At both the collegiate and professional level football is part of a multi-billion dollar industry; therefore, the serious, long-term health effects of the sport are discussed within a highly politicized, mediatized, and emotional arena. It is my hope that this research will illuminate these underlying issues, provide clarity, and enrich the discussion of risk in football.
- Presenter
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- Elynn Wu, Junior, Atmospheric Sciences Mary Gates Scholar
- Mentors
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- Dargan Frierson, Atmospheric Sciences
- Alyssa Atwood, Atmospheric Sciences, Oceanography
- Session
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- MGH 241
- Easel #144
- 12:45 PM to 2:15 PM
Paleoclimate data suggest that anomalously cold conditions across the North Atlantic and a southward shift of the Intertropical Convergence Zone (ITCZ), a major feature of the tropical atmosphere, occurred during the Little Ice Age (LIA) ~ 1350 – 1850 AD. The purpose of this research is to identify whether climate changes during this time can be attributed to changes in external forcings such as solar insolation, volcanic aerosols, and greenhouse gas concentrations. To address this question, I am evaluating changes in North Atlantic surface temperature and changes in the position of the ITCZ over time with eight climate models used in the latest Intergovernmental Panel on Climate Change Report. In each model, two types of runs are analyzed: pre-industrial control runs and last millennium runs. The pre-industrial control runs are 1,000-year runs with external forcings held at 1850 AD levels. In order to identify the models with realistic climatology in the tropical Pacific (a key area to monitor changes in the ITCZ), I compared the mean precipitation and surface temperature fields from the pre-industrial control runs with modern observational data. The results suggest that CCSM4, GISS, MPI, and FGOALS have the smallest mean state biases in the tropical Pacific and thus further analyses will be limited to these models. In addition, I am analyzing the last millennium runs of these models, which are 1,000-year runs with external forcings that change over time in accordance with paleoclimate records. Our hypothesis is that the LIA climate anomalies occurred due to changes in external forcing, thus, colder North Atlantic temperatures and a southward shifted ITCZ should be observed between 1350 – 1850 AD in the last millennium runs, and be unprecedented when compared to the pre-industrial control runs.
- Presenter
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- Yi-Hsuan (Sue) Wu, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentors
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- Trevor Toll, Materials Science & Engineering
- Jihui Yang, Materials Science & Engineering
- Session
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- Balcony
- Easel #89
- 12:45 PM to 2:15 PM
Thermoelectric materials have the ability of converting wasted heat into electricity. The energy conversion efficiency of thermoelectric materials is determined by its figure of merit- ZT. The equation of figure of merit is ZT = S2T/ρκ, where S is the thermopower, T is the absolute temperature, ρ is the electrical resistivity, and κ is the thermal conducivity. Currently, existing homogeneous bulk thermoelectric materials have the highest ZT, at around 1.5. This project consists of designing high efficiency hierarchical thermoelectric composites with a ZT value greater than 2 by using energy filtering at interfaces to block the low-energy charge carriers, and, thus, increase the average energy transported per charge carrier. This results in an increase in thermopower(S) and, hence, an increase in power factor of ZT. Using solution-based solvothermal chemistry, which allows for control of the dimensions and morphologies of the nanoparticles through variations of the reaction parameters, we prepared low-dimensional thermoelectric nanobulk Bi2Te3. The surfactant-free scalable synthesis of Bi2Te3 provides quick and bottom-up synthesis with 90% yield. After these chemical processes, a dry nanoparticle sample will be consolidated by Spark Plasma Sintering, and turn into a pellet. The lowest sintering temperature determination will benefit to define the processing limitation in the further nanocomposite design. More comparison of the electronic transport properties measurements in bulk and nano Bi2Te3 will be carried out later. If the high-yield synthesis with doping capability can be achieved; also, if the processing limitation is known, it has high potential to achieve thermoelectric material with ZT higher than 2.
- Presenter
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- Charles Hong (Charles) Yuen, Senior, Mat Sci & Engr: Nanosci & Moleculr Engr
- Mentor
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- Peter Pauzauskie, Materials Science & Engineering, U. Washington
- Session
-
- Balcony
- Easel #86
- 12:45 PM to 2:15 PM
Nanoscience and nanotechnology has evolved rapidly in recent decades. It promises a greater understanding and higher degree of customization in future materials. One field of interest is the ability to mimic the biological composition of bone tissue using nanoscale hydroxyapatite (HA). With the ability to manufacture and impregnate with proteins, the mimicked tissue can be utilized in vivo without the side effects of traditional organ transplants and biocompatible materials. HA nanowires were fabricated using a hydrothermal synthesis process. First, the precursor composed of calcium phosphate was synthesized via a sol-gel process to create a powder. After suspending the powder in solution of DI water and ammonium hydroxide, the solution was loaded into an autoclave and heated at 170 degrees Celsius for various time periods. The product was then characterized using optical microscopy, scanning electron microscope (SEM) X-ray diffraction (XRD), and Raman spectroscopy. First, SEM was used to determine if particles were successfully synthesized. Next, the size of the nanowires was characterized. It was found that the nanowires had an aspect ratio of 5:1. XRD powder diffraction showed that the samples matched the industry standard peaks for HA. Lastly, Raman spectroscopy was conducted but the results are yet to be analyzed. The work has successfully synthesized nanowires of hydroxyapatite utilizing a hydrothermal process. Through use of the above characterization methods, we find that an alteration to the synthesis must be performed to obtain HA nanowires with larger aspect ratios. – 20:1. Successive syntheses are being conducted by varying pH levels and time periods to achieve the desired lengths.
- Presenters
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- Bijia Zhang, Junior, Earth & Space Sciences
- Jerilyn Rose (Jerilyn) Coberly, Junior, Earth & Space Sciences (Environmental)
- Mentors
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- Ruth Martin, Earth & Space Sciences
- Elizabeth Nesbitt, Earth & Space Sciences
- Session
-
- Balcony
- Easel #104
- 12:45 PM to 2:15 PM
The purpose of this study is to investigate the effects of different pollutant sources in Sinclair and Dyes Inlets, both located in Puget Sound, Washington. Puget Sound is a fjord-like waterway extending from Olympia, Washington to the Canadian border. Sinclair Inlet and Dyes Inlet are connected by the Port Washington Waterway near Bremerton in Kitsap County, Washington. Bremerton is the home of Puget Sound Naval Shipyard. This naval base is a Superfund site that discharged large amounts of industrial pollution into Sinclair Inlet. In comparison, agricultural and residential pollution are deposited in Dyes Inlet from streams surrounding the perimeter of the inlet. This study aimed to analyze foraminiferal assemblages to determine if environmental changes through pollution and other factors have affected the health of the Bremerton area marine ecosystems. Foraminifera are shelled single-celled marine microorganisms that react to environmental stresses, thus they act as good indicators of environmental change. Foraminifera were collected from a total of 21 samples provided by the Washington State Department of Ecology from 1998-2009. Thirteen of these samples were taken from Dyes Inlet and 8 were taken from Sinclair Inlet. This study focused on examining the density and diversity of foraminifera from 1998-2009. Our results show that Dyes Inlet contains a low diversity of foraminifera with 7 different species found. However, 2 samples did not contain any foraminifera and several samples from more recent years only contained one species. In Sinclair Inlet, 15 species were identified in total, but diversity was nearly cut in half over the time period studied. The dominant species in both inlets was Elphidium hannai. By comparing foraminiferal assemblages from our locations with samples from less anthropogenically impacted locations in the Puget Sound, we can begin to analyze the potential effects of different types of pollution on the health of Puget Sound.
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