Hearing loss affects approximately 37.5 million adults in the United States and is associated with significant comorbidities, including depression, anxiety, and social isolation. Among the various etiological factors, aminoglycoside antibiotics are an important contributor to irreversible hearing loss due to their ototoxic effects on inner ear hair cells. Upon entry neomycin accumulates in the cytoplasm and lysosomes, and induces an acute hair cell death. G418, on the other hand, accumulates in lysosomes before triggering delayed death. This difference suggests a previously underexplored role of lysosomal signaling in hair cell survival. Due to the difficulties to access the mammalian inner ear, we are using the larval zebrafish lateral line to study live hair cells. My study investigates the role of lysosomal calcium release in mediating protection against aminoglycoside-induced hair cell damage. Specifically, we focus on Two Pore Channel 2 (TPC2), an ion channel located on the lysosomal membrane, which allows for calcium release upon activation by the agonist TPC2-A1-N. Using dose response curves, we examined the effect of TPC2-mediated calcium release on hair cell survival following G418 exposure. Our findings indicate that activation of TPC2 is able to protect against G418, but not neomycin. Moreover, protection is time sensitive, since activating TPC2 before G418 accumulation confers protection to hair cells, whereas co- and post-exposure activation does not yield a protective effect. These results suggest that lysosomal calcium release plays a critical role during aminoglycoside-triggered delayed hair cell death. This study provides novel insights into lysosomal calcium signaling as a potential mechanism for mitigating aminoglycoside ototoxicity and highlights TPC2 as a promising therapeutic target for hearing loss prevention.

Increased mitochondrial oxidative stress causes fatigue and metabolic dysfunction in muscle tissue. It is unclear whether the oxidative stress is due to elevated production or impaired consumption of reactive oxygen species (ROS). The purpose of this study is to test whether the capacity of the antioxidant defense system is impaired or the mitochondrial ROS production rate is elevated in response to chronic changes in mitochondrial oxidative stress. To experimentally manipulate mitochondrial oxidative stress, we use an inducible mouse model to knockdown superoxide dismutase 2 (SOD2) in skeletal muscle and heart to increase oxidative stress, and exercise training to decrease oxidative stress. Knockdowns (KD) or littermate controls (CON) performed a six-week voluntary wheel running (EX) or sedentary control intervention (SED). Following completion of the intervention, I isolated heart and skeletal muscle mitochondria using differential centrifugation. I measured mitochondrial hydrogen peroxide (H₂O₂) production rate and tested the antioxidant capacity by treating isolated mitochondria with Auranofin (AFN) or 1-chloro-2,4-dintrobenzene (CDNB), which inhibit the thioredoxin and glutathione S-transferase components of the mitochondrial antioxidant defense system, respectively. KD heart and skeletal muscle had similar absolute H₂O₂ production rates compared to CON, but normalized to oxygen consumption the KD had significantly higher H₂O₂ production. Since absolute H₂O₂ production under vehicle conditions was not different, this suggests that the antioxidant capacity adapts to meet the changes in mitochondrial H₂O₂ production. We will collect data from the exercise-trained cohort next month. I expect to see an increase in H₂O₂ production rate and antioxidant capacity in both groups due to the increased mitochondrial biogenesis from exercise training. These results demonstrate that chronic increases in mitochondrial oxidative stress decrease mitochondrial H₂O₂ production capacity from skeletal muscle.

The external fertilization and transparent embryos of zebrafish make them an informative model of vertebrate embryonic development from the 1-cell stage. In this study, we examine the impact of de novo GTP synthesis on the formation of the embryonic somites, which are embryonic cells which develop into segmented blocks of muscle that run the length of the body. We hypothesize the de novo GTP synthesis is required for the correct patterning of somite borders in zebrafish embryos, and that this process facilitates the formation of a vertebrate body plan. Inosine monophosphate dehydrogenase 2 (IMPDH2) is the enzyme which catalyzes the conversion of inosine monophosphate (IMP) towards the de novo synthesis of GTP instead of ATP. To test the impact of de novo GTP synthesis on somite formation, we inhibited IMPDH2 function with mycophenolic acid (MPA) both before and after somite formation began. MPA caused stronger defects in the somite morphology and embryonic body shape when added to embryos before somite formation began, earlier in development. We performed in situ hybridization against xirp2a to assess the effect of inhibiting IMPDH2 function on the formation and patterning of the somite borders. MPA treatment decreased the definition of somite borders we could observe in the posterior tail. Inhibiting IMPDH2 with MPA produced somites with smooth, round borders instead of the chevron-shape typical of zebrafish. We next conducted immunohistochemistry against IMPDH2 to examine the expression and localization of this enzyme in embryonic cells when GTP conditions are low. In MPA-treated embryos, we observed increased expression of IMPDH2 across the entire embryo. We will next explore how GTP abundance affects activity of the clock, a mechanism which synchronizes gene expression of embryonic cells.

Mycobacterium abscessus is a non-tuberculous mycobacterial (NTM) species that causes severe pulmonary infections, particularly in immunocompromised patients and those with preexisting lung diseases such as cystic fibrosis. Treating M. abscessus infections is challenging due to its intrinsic antibiotic tolerance and capacity to develop multidrug resistance. To identify novel molecules that can target this pathogen and enhance current treatments, we screened a library of FDA-approved drugs (n = 2,400). Our data shows that Netupitant, a drug commonly used to prevent chemotherapy-induced nausea and vomiting, exhibits potent antibacterial activity against a broad range of M. abscessus clinical isolates, including multidrug-resistant strains, with a minimum inhibitory concentration (MIC) ranging from 4 to 16 µg/mL. Furthermore, in combination with amikacin, a standard treatment for M. abscessus infections, Netupitant demonstrated strong synergistic interactions, as confirmed by checkerboard microdilution and time-kill assays. These findings highlight Netupitant’s potential as a novel therapeutic option for M. abscessus, particularly in combination with existing antibiotics. Future studies exploring its mechanism of action and in vivo efficacy could further advance antibacterial drug discovery for difficult-to-treat NTM infections.

My research project focuses on age-related changes in muscle function. We have previously designed and used novel young and naturally aged in vitro three-dimensional engineered muscle tissues (3D-EMTs) using donated myoblasts from the Study of Muscle, Mobility, and Aging (SOMMA) to investigate this. A question raised in this research is the how closely force measured in 3D-EMTs correlates to in vivo force of intact skeletal muscle. To address this, I stimulated young and aged mice's gastrocnemius muscles to contract (Aurora Instruments) measuring maximum force, contraction/relaxation kinetics, and fatiguability. Mice were then sacrificed and hindlimb muscles dissociated to isolate skeletal muscle myoblasts for cell culture. Myoblasts were amplified and used to generate young and aged rodent 3D-EMT. We tested in vitro 3D-EMT muscle mechanics using a Magnetometric Analyzer for engiNeered Tissue ARRAY (MantARRAY, Curi Bio). In vitro muscle force data was compared to in vivo force data from the same mouse. Results generated by this project helped identify the correlation between in vivo and in vitro force measurements and how they are impacted by age. This study also allowed us to bank multiple cell lines for future high throughput studies to utilize these rodent 3D-EMT models to study the progressive loss of muscle mass and function known as sarcopenia. The results from this project and the cellular models created will be used in the future to investigate potential targets for therapeutic interventions to treat sarcopenia in an ever-expanding aging population.

Our brains have evolved to navigate survival and respond to danger, but trauma dysregulates these systems, causing the brain to misinterpret everyday experiences as threats. This dysregulation results in hypervigilance, which can manifest as panic attacks, dissociation, and other debilitating symptoms. Current treatment options for trauma often focus on symptom management, overlooking the physiological impacts of trauma. These treatments can be expensive, inaccessible, and may have side effects. This literature review examines holistic, non-pharmaceutical, neuroplasticity-based (NPNB) approaches, such as breathwork, nutrition, exercise, and sleep, to challenge traditional methods and advocate for integrating holistic interventions into mainstream trauma care, emphasizing accessibility and autonomy for trauma survivors. As we explore the increasing need for mental health care, we look at the interplay between psychological trauma and physical health by exploring the mind-body connection and trauma-induced inflammation. Additionally, this exploration aims to understand how these treatments can reshape neural pathways, improve emotional regulation, and enhance psychological and physiological well-being. It also examines potential paradigm shifts in trauma care and advocates for increased accessibility to alternative treatments, particularly for individuals who cannot access conventional therapies. We expect to find that NPNB treatments are underutilized in the treatment of trauma and, if expanded upon, would have the potential to improve accessibility, reduce or eliminate side effects, and help survivors regain a sense of autonomy.

During embryonic development, gene expression is temporally and spatially coordinated to control organogenesis and fetal growth. We previously identified a subset of 140 genes that conferred lethal and sub-viable phenotypes in mice and are likely to be haploinsufficient in humans. These genes presumptively play essential roles in fetal development, but their function is unknown. I aim to uncover the role of these genes in mouse embryonic development using Weighted Gene Co-Expression Analysis (WGCNA). Co-expression analysis will be conducted on mouse embryonic stem cell RNA sequencing data obtained at three different stages of in vitro differentiation and across two different genetic backgrounds, creating a subset of nine samples encompassing 12555 genes. Choosing three different time points allows us to see how expression of our genes of interest changes over time, and choosing two different genotypes (wild type and knock-in) allows us to investigate if expression changes due to a single point mutation. We performed dynamic clustering on this RNA sequencing data to identify co-expressed gene clusters. I will map these gene clusters to biological pathways to make inferences about which cellular processes, metabolic functions, or structural components the genes of interest are involved in. This may indicate the role of these genes in fetal development and help reveal why fetal viability is compromised. In future studies, the functional characterization of these genes will generate new ideas and hypotheses about the basis of genetic disease.

Cascadia Subduction Zone, a major fault off the Pacific Northwest coast, has a history of producing powerful earthquakes. These events highlight the need to understand the region's earthquake probability. This study aims to conduct a sensitivity test on the earthquake probability in the Pacific Northwest, evaluating partial and full rupture scenarios. The study analyzes 32 different earthquake chronologies derived from the earthquake catalog and perturbs them to assess how the probabilities vary with changes in data. As a result, we found that the Southern Oregon and Northern California regions face the highest risk, with a 34-49% chance of a partial rupture and a 28-32% chance of a full rupture within 100 years. Within the next 50 years, probabilities are 17-20% and 13-15%, respectively. The relatively small changes in probabilities suggests that the estimates are robust, indicating that changes in data do not significantly skew the overall probability assessment. These findings emphasize the need to implement hazard mitigation strategies to protect vulnerable Southern Oregon and Northern California communities from future earthquake events.

Ernst Chladni visually demonstrated sound wave patterns by using sand on vibrating metal plates. Inspired by his technique of using a violin bow to excite a Chladni plate, this artistic research project explores how cello sounds can also generate Chladni patterns. I will compose and perform a new piece for cello, inspired by the revealed Chladni patterns. During the performance, corresponding visual patterns of sound will be projected for the audience.

Industrial chemical separation processes, such as distillation, drying, and evaporation, consume 10-15% of US annual energy production. Membranes, which act as a selective barrier to separate compounds, are substantially more energy efficient than traditional chemical separation methods that require heat and could help reduce this consumption. Inorganic membranes are inherently suitable for many separation processes because they are chemically and thermally stable; however, ceramic membranes are mechanically fragile and costly to produce. Commercial polymeric membranes are comparably more economical but degrade in harsh organic solvents and high-temperature environments. One approach to achieve the necessary membrane properties at low cost is vapor phase infiltration (VPI), a gas-phase synthesis technique consisting of sorption, diffusion, and entrapment of vapor-phase reactants within organic polymers. The infiltration of inorganic oxides through VPI has been shown to enhance the properties of polymeric membranes by producing cost-effective, chemically stable, and temperature-tolerant organic-inorganic hybrid materials. However, the mechanical properties of these hybrid membranes, which are crucial for maximizing lifetime and durability, are generally less well understood. In this study, polyethersulfone (PES) membranes are subjected to trimethylaluminum and water under various VPI process conditions in a custom-built reactor. Thermogravimetric analysis is utilized to quantify the extent of inorganic infiltration by measuring the aluminum oxide loading within PES membranes. Mechanical properties of these membranes are characterized by tensile stress, modulus, and maximum pressure through dynamic mechanical analysis and burst pressure testing. Enhancement in chemical stability is determined by measuring the degradation of VPI-treated PES samples after exposure to organic solvents. These results provide insight into the relationship between infiltration structure, membrane stability, and mechanical properties, which may allow for improved membrane design and more sustainable industrial chemical operations.

Per- and polyfluoroalkyl substances (PFAS) are highly toxic contaminants shed from man-made chemicals which are still being used in consumer and industrial applications. Unfortunately, strong carbon-fluorine bonds present within PFAS prevents their natural degradation in the environment, leading to PFAS accumulation. Membranes, particularly those used for desalination, have been shown to be effective at removing many types of PFAS from water and are less expensive and energy intensive when compared to other removal approaches. However, new membrane materials are needed that can remove even the smallest PFAS molecules. In this project, we are developing new membrane materials aimed at being more effective than commercial nanofiltration and reverse osmosis membranes using molecular layer deposition (MLD), a technique that can deposit and precisely control membrane chemistry. First, commercial membranes from DuPont (NF245, NF270, and Seamaxx) were tested for their pure water permeability as well as rejection of salts and PFAS of varying carbon chain lengths, the results of which were used as an experimental control. Next, polymer membranes were made using MLD. These MLD-based membranes were synthesized and tested, and their results were compared to the commercial membranes for efficacy. This work hopes to develop new membrane chemistries that are more effective at removing PFAS than existing commercial materials.

Scarcity of usable water has quickly become one of the world’s greatest problems. Most of Earth’s water is saltwater, and much of the limited available freshwater contains harmful contaminants. One type of contaminant, per- and polyfluoroalkyl substances (PFAS), are particularly hazardous as they are toxic to humans and do not naturally decompose due to their strong carbon-fluorine bonds. Of the available methods of removing PFAS from water, including adsorption, ion exchange, and membrane filtration, membrane filtration is an appealing separation technology since it does not require expensive, energy intensive regeneration steps used in adsorption and ion exchange. Our project aims to use molecular layer deposition (MLD) to create polymeric thin films selective to  PFAS for water filtration. MLD involves cycles of dosing and purging reactant vapors to create a thin film layer by layer, allowing for better control over the surface uniformity, composition, and thickness. These thin films, synthesized on polyethersulfone (PES) membranes, will ideally be rejective of PFAS while preserving membrane permeability. We synthesize thin films of various chemistries and measure their water contact angle to determine the impact of hydrophilicity on long- and short-chain PFAS rejection. Here, we provide our measurements of the pure water permeability, long- and short-chain PFAS rejection, and water contact angle of MLD-treated PES membranes.

Type 1 Diabetes is characterized by a dysfunctional response of the immune system, with our project focusing on CD8+ T-cells. Studying epigenomics provides us with information about differential gene expression, as well as distal enhancers and their targets. Understanding this genetic background enables more efficient means of treatment. In this paper, we look at three different kinds of sequencing: ATACseq, RNAseq, and Hi-C. Our focus up until this point has primarily rested upon the first, as we have used it to analyze chromatin accessibility across the genome in patients with T1D and healthy controls. To do so, we have found peaks within the reads for both demographics, which we then used to examine the individual peaks for each subject and the consensus peaks between each condition to see which are especially prominent. These peaks are then the focus of our differential expression analysis, which will allow us to understand the areas of significance and perform further exploration: variance calling and footprinting. As we continue with this project, we hope that RNAseq and Hi-C will provide us with information on gene expression levels and the physical structure of chromatin, respectively. The former was run and sequenced within our lab, but the latter is pre-existing data we will be drawing from for this analysis. Understanding the regulatory landscape allows for better informed treatments, not just for T1D but for autoimmune diseases as a whole.

Umbilical vein catheterization (UVC) is a life-saving procedure performed in neonatal intensive care units (NICUs) to provide emergency vascular access for critically ill newborns. The procedure requires accuracy in catheter placement and detailed knowledge of the relevant anatomy. Improper catheter placement can lead to severe complications such as hepatic necrosis, thrombosis, and cardiac tamponade. Current UVC training models lack the anatomical accuracy and tactile realism needed for effective hands-on training. My research aims to develop a realistic UVC training model that improves procedural accuracy and reduces neonatal complications. To address these limitations, I conducted a cognitive task analysis (CTA) with NICU clinicians to evaluate existing training gaps. The CTA revealed difficulties in distinguishing the umbilical vein from the smaller, thicker-walled umbilical arteries, a key factor in accurate catheter placement. The umbilical vein’s thin walls and similar coloration to arteries often lead to misidentification, resulting in incorrect catheterization. Additionally, practitioners reported difficulties in gauging the appropriate insertion depth, which vary based on neonatal size and condition, leading to potential complications if the catheter is advanced too far. Current models lack realistic tactile feedback, making it difficult to differentiate the collapsible umbilical vein from the rigid arterial walls. Without accurate resistance simulation, trainees struggle to develop the necessary sensitivity to detect vein entry and confirm catheter placement effectively. Based on the CTA findings, I am developing a model with depth markers, a simulated blood flashback system, and a suturable outer layer to improve training realism. This research contributes to neonatal care by improving hands-on UVC training, ultimately enhancing practitioner confidence, reducing neonatal morbidity, and raising the standard for UVC procedures. Usability testing with NICU practitioners will evaluate the model's effectiveness and guide refinements for optimal training outcomes. With refinement, this tool could become a vital NICU resource, ensuring high-quality neonatal care everywhere.

Machine learning models are increasingly applied across scientific disciplines, with deep-learning based pose estimators revolutionizing the fields of neuroscience and marine biology, allowing researchers to automate and enhance accuracy of behavioral analysis. While markerless pose estimators have transformed behavioral neuroscience, their effectiveness is limited by a lack of species- and domain-specific data, especially for marine invertebrates such as cephalopods and starfish. Due to their highly flexible body structures, starfish cannot be effectively represented by the rigid skeletal models commonly used for terrestrial vertebrates, making existing pose estimation techniques unreliable for tracking their movements. This project addresses this by developing a deep learning-based pose estimation model and archive database specific to cephalopods and starfish. Using DeepLabCut, we train a supervised machine learning model to track movement patterns in both naturalistic and laboratory settings. Our dataset, sourced from the Hodin lab in Friday Harbor, undergoes preprocessing with embedding and clustering algorithms to identify representative frames for model training. By establishing a reliable, quantitative framework for cephalopod behavior analysis, this product can enhance reproducibility and contribute to the development of standardized methodologies and definitions of behaviors in marine and neuroscience research. This tool would ease cross-lab collaboration and eliminate ambiguities when investigating cephalopod and starfish behavior.

Hearing loss is a prevalent disability that is commonly caused by damaged hair cells, which are mechanosensory cells critical for hearing and balance. Among the ways in which hair cells can die—including aging, genetic predisposition, and noise exposure—is damage due to ototoxicity, which is when medications damage hair cells. Aminoglycosides, a commonly-used family of antibiotics, is known to cause hearing loss in patients that undergo multi-day treatments. Our lab and others have shown that certain aminoglycosides (e.g. neomycin) can cause acute hair cell death, whereas other aminoglycosides (e.g. gentamtcin) kill in a more delayed manner. In the case of delayed hair cell death, it has been shown that these aminoglycosides accumulate exclusively in the lysosome, which is the organelle that contains digestive enzymes. It is thought that a lysosomal stress response contributes to hair cell protection through calcium release and then the recruitment of lysosome-membrane-repairing proteins known as ESCRTIII. In my project, I use zebrafish live imaging to elucidate if ESCRTIII proteins are recruited onto lysosome membranes in aminoglycoside-treated hair cells. First, I create a transgenic zebrafish line containing IST1-GFP in its genome. IST1 is a part of the ESCRTIII complex and serves as a biomarker to track where ESCRTIII proteins are active in a cell. If the aforementioned hypothesis is true, then in aminoglycoside-exposed hair cells, we expect to see ESCRTIII proteins localized around lysosomal membranes following lysosomal stress response and calcium release. Elucidating the lysosomal repair mechanism in the context of aminoglycoside exposure is valuable for understanding how hair cells could survive ototoxic conditions. In the future, it may be possible to harness ESCRTIII proteins to prevent hearing loss induced by ototoxicity.

Hearing loss affects approximately 40 million people in the US. It is primarily caused by the damage and loss of hair cells, which do not regenerate in humans. In the Raible lab, we use zebrafish as a model to study hair cell development, death, and regeneration. Unlike mammals, zebrafish can regenerate their hair cells after damage. I am currently using CRISPR-Cas9 gene editing technology to create mutant zebrafish to test a gene’s role in hair cell development and regeneration. We use guide RNA to target and mutate different genes that have been shown to be expressed in hair cells or support cells, which act as a new source of hair cells during regeneration. At 5 days post fertilization we quantify the number of hair cells and compare the numbers between mutant and non-mutant fish to test for developmental defects. If there are no defects, we treat these fish with the ototoxic antibiotic neomycin to kill their hair cells. After neomycin treatment, we wait 48 hours for the hair cells to regenerate and then compare the number of hair cells in non-mutant fish to mutant fish to examine whether the loss of that gene impacts hair cell regeneration. By developing an understanding of what genes are important for hair cell function and regeneration in zebrafish, we can begin to apply these findings to help with studies looking into hearing loss in humans.

Cryptic diversity, the existence of genetically distinct but morphologically similar taxa that thus were previously classified as a single entity, is a fascinating subject in evolutionary biology and alpha taxonomy, but can be challenging to assess in practice. Genetic analyses have proven successful in identifying cryptic taxa, but are often impractical to employ as a starting point. Morphology thus can play an important role in cases of possible cryptic diversity, especially in determining if further study is warranted. Here, we use statistical analyses on morphological data to assess a possible case of cryptic diversity within Allium acuminatum, a species of wild onion native to western North America. Specimens collected primarily from several counties in Washington State (Kittitas, Yakima, and Klickitat) have been noted to differ morphologically from formal descriptions of the species. Morphological data was recorded for 165 specimens from the University of Washington Herbarium, Burke Museum collection. The data was then analyzed using a Factor Analysis with Mixed Data (FAMD) algorithm, and the results of the FAMD were then analyzed with a k-means clustering algorithm. The k-means clustering results were then plotted on a geospatial map using the original locality data from the herbarium specimens, and geospatial patterns for the clusters were assessed visually. Finally, t-tests and chi-squared tests were performed for the continuous and categorical traits, respectively, between the k-means cluster groups. The k-means clustering algorithm generated 3 clusters from the FAMD data, one of which was strongly centered around the area of interest (Kittitas, Yakima, and Klickitat counties), according to the geospatial map. Further, the statistical tests showed that, for 10 of the 14 traits analyzed, there were notable differences between the k-means cluster groups with a high level of statistical significance (p ≤ 0.0001).  Most of these differences were reflected in the cluster centered around the area of interest. These results indicate there is detectable morphological variation within A. acuminatum, and this variation is centered around the geographical area of interest. Additionally, we believe these results indicate further study is warranted to determine if the morphologically different populations are worthy of taxonomic recognition using more sophisticated methods, such as molecular techniques.

Scaling and power law concepts are fundamental in undergraduate physics and have important applications in biology, including thermoregulation and metabolism. Because of this, scaling is emphasized in the introductory physics sequence for life science students. To inform instruction, we examined student understanding of scaling relationships, focusing on surface area, volume, and mass. Our study analyzed student responses to multiple-choice and free-response questions on quizzes given before and after lecture instruction. Preliminary findings indicate persistent difficulties in recognizing the linear relationship between mass and volume in uniform-density objects. Additionally, students struggle to track changes in surface area for three-dimensional objects. These challenges suggest gaps in conceptual understanding that may hinder students' ability to apply scaling principles across disciplines.

Stress resilience, the ability of cells and tissues to adapt to stimuli, declines with age. Skeletal muscle contraction is a physiological stressor when repeated through exercise training enhances stress resilience and mitigates age-related comorbidities. However, as the body's capacity to mount adaptive responses diminishes with age, the extent to which this decline affects physiological adaptation to stress remains unclear. This would guide future therapeutic strategies surrounding muscular degeneration over the lifespan. The goal of this study is to assess the magnitude of stress response activation across metabolic, oxidative, proteostatic, and heat shock stress response pathways. We use gene expression analysis to evaluate the transcriptional response to controlled in vivo muscle stimulation, providing insight into age-related differences in stress resilience. Young (6mo) and old (23-24mo) male and female mice (C57Bl/6JNia) underwent an in vivo fatiguing muscle stimulation (Stim) or served as an unstimulated control (Unstim). Three hours following the stimulation both right and left limb muscles were collected and processed for gene expression analysis. Following stimulation and collection, I performed tissue processing, RNA extractions, and RT-qPCR assays on muscle tissue. There was a significant increase in PGC1a, HMOX1, TRIM63, and HSPa1a genes in response to muscle stimulation when compared to the unstimulated limb within the same animal. The magnitude of these changes in response to stimulation were not different across age or sex. Analysis of basal changes in unstimulated groups across age and sex is planned for next month. These preliminary results suggest no significant age or sex differences across multiple pathways of stress resilience in skeletal muscle. A strength of this study design is that we use a combined within- and between-animal analysis of both stimulated and unstimulated conditions to control for any potential variations associated with each age, sex, and stimulation condition, increasing confidence in our results.