Chronic stress has been shown to adversely affect cardiovascular, neurological, and mental health, especially in older populations. The success of alternative therapies in combating stress has been well-supported in neuroscience thus far. In this experiment, the Portland Arithmetic Stress Task (PAST) was used to examine stress reactivity in older adults who received Mindfulness Meditation (MM) training. This was done in order to determine whether event-related potentials (ERP’s) and autonomic biomarkers may be impacted by this MM intervention. Thirty-one older adults were enrolled and randomized into three, six-week program groups: MM, Health/Wellness Education (H/W), and no program (no training control). All groups were brought in for testing before and after intervention. Each visit, a set of self-assessment scales of stress were completed before and after the stress task was administered. The PAST was administered, and an EEG recorded changes in feedback-related negativity (FRN), while an ECG recorded heart rate before, during, and after the stressor. While a previous study supported that the PAST test was effective in eliciting a significant stress response, the changes in physiological measures and ERP’s were modest, leaving a small range to work with in future studies. It is unclear if MM will be effective enough, in such a short time, to create a measureable difference in stress reactivity via this EEG measure.We expect, given previous literature on MM and stress, that in the MM group there should be a decrease in physiological and ERP stress reactivity measures during the test, as well as a faster rebound to baseline after the test were administered. We would also anticipate self-reported stress assessments should also improve in the MM group and H/W groups.

Diatoms are responsible for roughly 45% of all oceanic primary production and play a unique role in carbon cycling. This crucial role makes understanding their behavior and interactions vital. In the environment, diatom samples are typically xenic (marine bacteria present around and on the diatoms). These diatom-bacterial interactions have been shown to have striking effects on diatom growth rates due to bacterial release phytohormones. These plant-based signaling molecules are well characterized in terrestrial organisms but their marine impact is not fully understood. One such phytohormone, indole-3-actetic acid (IAA), is responsible for bacteria-plant mutualistic behavior on land. Previous work in our lab has shown that addition of IAA to axenic diatoms has no effect at moderate levels and is lethal at high levels. However, when diatoms are co-cultured with IAA-producing bacteria, their growth rate increased. Thus, IAA alone is not sufficient to induce increased growth. We used this information, and the known bacterial IAA biosynthetic pathway to select IAA derivatives and precursors (methyl-IAA, Tryptophol, Tryptamine, Indole-3-acetamide, indole-3-carboxylic acid, and Tryptophan) to test their endogenous expression in marine bacteria found on diatoms in the environment. Of the bacterial species tested, none expressed every compound and most expressed novel combinations. This project tests the effects of various IAA derivatives as well as a cytokinin (phytohormone),6-(γ,γ-Dimethylallylamino)purine (2ip), on diatom growth. We investigate suites of compounds, based on bacterial expression data, as well as individual compounds. We also seek to use phylogenetic tree building to identify the bacterial producers of these compounds using IAA-producing, terrestrial bacteria as a reference. Impacts of bacteria on diatom growth, blooms, behavior and the metabolites left behind from these interactions would aid in analyzing environmental transcriptomic data and ultimately result in a fuller understanding of diatoms and their response to chemical stimuli.

Understanding the mechanisms of plant biotic defense is imperative to help decrease agricultural crop damage by pathogens. Pathogens can potentially enhance infections by inducing DNA damage within the host. One example is DNA double-strand breaks caused by Pseudomonas syringae, a common bacterial pathogen in plants. Plants encode various mechanisms to repair double-strand breaks, including a pathway called homologous recombination repair that is regulated by the protein complex RPA (Replication Protein A) in response to abiotic stress. We further hypothesize that RPA plays a central role in regulating repair of pathogen-induced double-strand breaks. To test this, we will quantify hyper-susceptibility of mutant lines of Arabidopsis thaliana in response to pathogen infection (P. Syringae), employing a plant infiltration assay. This assay involves whole plant infiltration, followed by measurement of CFU counts of persisting bacteria within the leaf tissue. Of particular interest in this study is the role of one subunit of RPA, termed RPA1E, since mutants of the encoding gene display strong hypersensitivity to agents that induce double-strand breaks. Our current results suggest other RPA subunits (RPA1C) display hyper-susceptibility to pathogen infection. These results will ultimately provide initial insight in how agricultural crops defend themselves from microbial invasion by determining whether RPA1E responds to a pathogen infection and if it is required in the defense response of A. thaliana.

Climate change is forecasted to have an impact in agricultural productivity. To ensure security of crop yields, we must develop a better understanding of flowering mechanisms in plants. Research on flowering mechanism has been performed mostly under simplified lab growing conditions. However, in the natural environment, plants experience dynamic changes in abiotic factors like temperature throughout the day. To better understand how flowering is regulated under natural conditions, we focused on the expression profiles of FLOWERING LOCUS T (FT), which correlates with the flowering time in plants. FT expression is known to peak in the evening under long day lab conditions (16 hours of light, 8 hours of darkness, 22^oC constant). However, under natural long day conditions (Summer Solstice in Seattle, 16 hours of light, 8 hours of darkness, average highest temperature 21^oC) we have observed an additional morning peak. We have been able to recreate the observed expression of FT in the lab by modulating temperature oscillation and light quality of long day lab conditions. In this project, we first asked if the observed FT pattern is widely conserved in different wild type accessions in Arabidopsis thaliana. We grew different accessions under re-created lab growth conditions and analyzed FT expression using quantitative PCR. So far we have seen similar FT expression patterns among some accessions, suggesting that morning peak of FT is conserved among these lines. Second, we studied which timing of the day temperature acts as a cue to affect morning FT expression. We grew plants under various temperature conditions and compared results to the observed FT expression in nature. The results from this project will contribute to the development of new modified lab growth conditions that represent natural conditions and give a better understanding of the mechanism that controls FT regulation in nature.

Alternative pollinators such as the mason bee (Osmia spp.) are becoming increasingly important in agriculture as European honey bees (Apis mellifera L.) continue to decline. Osmia lignaria are especially important pollinators because they make contact with the anther and stigma during nearly every flower visit and are less likely to rob the plants of nectar without pollination. Previous studies indicate O. lignaria preferentially visit plants in the Rosaceae family, such as apple, cherry, pear and plum. The objectives of this study were (1) to analyze pollen loads in relation to proximity of natural areas surrounding the blueberry field and (2) to determine their pollen preference in a blueberry monoculture ecosystem. This study was conducted in a commercial blueberry field in southwestern Michigan. Pollen samples from flowering plants and O. lignaria nests were collected. Acetolysis was performed on all pollen samples, and pollen from O. lignaria nests was qualitatively and quantitatively analyzed. At this study site, O. lignaria collected pollen from white clover (Trifolium repens) and black cherry (Prunus serotine) most often. In spite of its availability, pollen collected from blueberries (Vaccinium corymbosum) accounted for significantly less of the total pollen. These findings are useful in determining the viability of Osmia species as crop pollinators. Based on the results, Osmia lignaria would not be a good option for blueberry pollination.

We know that climate sensitivity can vary within species, but the factors that influence which climatic variables influence population dynamics remain unclear. In this study, I assess whether macroclimate influences the climate sensitivity of four high elevation conifer species: Pacific silver fir (Abies amabilis), mountain hemlock (Tsuga mertensiana), Alaska yellow cedar (Callitropsis nootkatensis), and sub-alpine fir (Abies lasiocarpa). I also investigate if climate sensitivity of tree communities Mt. Rainier is changing over time. To address these questions, I analyzed tree core data from three high elevation sites at Mt. Rainier National Park. Each site is located in a distinctly different climatic zone on the mountain. I compared standardized tree growth to climate variables (mean growing-season temperature, total growing-season precipitation, annual snowpack, climate moisture deficit, etc.) using linear mixed effect models and “treeclim”, a tree ring analysis program in R. With these methods, I determine how influential climate variables differ by location, by species and over time. Gaining more insight into which climate variables have the greatest influence on growth in different areas will allow us to better predict how specific plant populations will react to ongoing climate change. Moreover, studying tree communities at high elevations is particularly important, since behavior at treeline will determine whether a species’ range expands, contracts or shifts, which in turn has implications for both that species and other species. For example, conifer range expansion on Mt. Rainier could positively increase carbon sequestration (by increasing woody cover in the park) while negatively encroaching on the alpine wildflower meadows, a major attraction for tourists. Widespread range contractions could potentially reduce the ability of those forests to sequester carbon from the atmosphere. Thus, with better predictions of tree shifts, we can make more informed management decisions for ecotourism and conservation.

The NASA Glenn Research Center’s Advanced Noise Control Fan (ANCF) started its research in the early 1990s at the Aero-Acoustic Propulsion Laboratory (AAPL). The ANCF was used to support noise reduction in engine fan components. ANCF was developed to identify successful concepts for engine fan acoustic testing. These concepts were then implemented into high speed fan designs that were tested at the 9x15 WT, which incurs a significantly higher cost. In this way, the ANCF has substantially contributed to the advancement of the understanding of the physics of fan tonal noise generation. Due to the technological advancements of high speed fan designs over the last several decades, there became a critical need for a new Fan Test Rig that would enable successful completion of the NASA/Industry noise reduction program goals. To make room for this new capability, it was decided that the ANCF would be loaned to the Notre Dame University institution to support continued testing for interested companies and to provide educational opportunities. This presentation will discuss how a Systems Engineering method was used to document and detail the dismantling, shipping and reassembly of the components of the ANCF into its new location.

With over 2,000 new discoveries the field of exoplanets is rapidly expanding. As the detection of new planets continues to increase, many seek to answer: What do these distant exoplanets look like? Current telescopes are not yet able to image the surfaces of exoplanets, but plans are underway for a future NASA telescope that will be capable of observing light reflected off terrestrial exoplanets using a coronagraph instrument to block out the starlight. Located at distances of many light years, these planets only appear as dots of light. Using the Virtual Planetary Laboratory’s (VPL) 3D Spectral Earth model, light reflected off the many unique surfaces and clouds on Earth were modeled and compressed into a single spatially-unresolved dot. By observing how the brightness of the planet changes as it rotates on its axis we were able to see different surfaces reflecting more or less light. A coronagraph-equipped telescope noise model was used to apply realistic observational noise to the spectra from the VPL 3D Spectral Earth Model. This allowed us to simulate data a future telescope would be capable of observing. After producing the data, periodograms were used to infer the planetary rotation rate, and Principal Component Analysis (PCA) helped us recognize how many unique surfaces an exoplanet has and approximately what color each surface is. Following the PCA, a more sophisticated surface mapping algorithm called the Surface Albedo Mapping Using RotAtional Inversion (SAMURAI) model was used to derive the underlying planetary surface covering fractions and their respective wavelength-dependent albedos that give rise to the time-dependent data that we observe. We show that many plausible configurations for the next-generation NASA telescope will be capable of mapping the area distributions and colors of oceans, land, and even vegetation, should these surfaces exist on any nearby exoplanets.