Life Sciences Commons^™

Effects Of Chronic Marijuana Use On Postural Control During Quiet Standing, Johnathon S. Ashcraft

Master's Theses

Marijuana, Cannabis Sativa, is the most commonly used recreational drug in the United States, with more than 60 million people reporting use in 2022 (Substance Abuse and Mental Health Services Administration, 2023). As marijuana consumption has increased, so have questions surrounding its acute and long-term effects. Its acute effects are well documented; however, the long-term effects are not as well understood. It is hypothesized that chronic marijuana users will exhibit a decrease in postural stability during quiet standing when compared to non-users, so the purpose of this study was to compare postural control of chronic marijuana users and non-users in …

Coyote (Canis Latrans) And Non-Target Wildlife Responses To Livestock Guardian Dogs At Sheep Grazing Sites On The California Central Coast, Tricia T. Nguyen

Master's Theses

Livestock depredation is one of the oldest and most widespread forms of human-wildlife conflict. The coyote (Canis latrans), a midsized canid, represents a significant proportion of domestic sheep depredations in the United States, costing livestock producers an estimated 24.6 million dollars annually. Management strategies for coyote-sheep depredation vary widely in their effectiveness and in their level of public support. Identifying appropriate strategies for farms, ranches, and other sheep grazing sites remains a pressing need due to the potentially negative consequences for surrounding ecosystems and socioeconomic outcomes for sheep producers. The livestock guardian dog (LGD) is a nonlethal control …

Exploring Fisheries Species Distribution Shifts In Response To Freshwater Inflow Through The Bonnet Carré Spillway Using Species Distribution Models, David T. May

Master's Theses

The Bonnet Carre Spillway (BCS) is a flood control structure on the Mississippi River (MR) ~52 km upstream of New Orleans. The BCS protects downstream communities from MR flooding by diverting floodwaters into Lake Pontchartrain when the MR exceeds 5.18m flood stage. Diverted waters flow east into the Mississippi Sound (MSS), introducing turbid, nutrient rich freshwater to the estuary before draining into the Gulf of Mexico. BCS openings have become much more frequent in the last decade, though little work has been done to explore the impact of the BCS on nektonic fisheries species. Here, a series of seasonal Maximum …

Assessment Of A Muscadine Grape (Vitis Rotundifolia) Mapping Population For Tolerance To Pierce’S Disease Pathogen Xylella Fastidiosa And Resistance To Black Rot Disease Pathogen Guignardia Bidwellii, Anushka Tennakoon

Master's Theses

Pierce’s disease (PD) and black rot disease cause severe economic losses for grape production under humid and warm conditions. Identifying resistance genes is crucial for controlling these disease by developing resistant cultivars. Muscadine grape (Vitis rotundifolia) cultivar ‘Pam’ has been identified to possess a high level of resistance to diseases. To elucidate the genetic basis of the resistance to the causal pathogens Xylella fastidiosa and Guignardia bidwellii in this cultivar, parents and 141 F1 individuals developed from open pollinated ‘Pam’ were evaluated for two seasons under natural disease pressure. The mapping population was genotyped using genotyping-by-sequencing (GBS) and …

Using Livestreaming Technology To Answer Novel Questions About The Behavior And Physiological Ecology Of The Prairie Rattlesnake (Crotalus Viridis), Max C. Roberts

Master's Theses

Recent advances in remote monitoring technology are opening up new opportunities for developing innovative natural history and biological research methodologies. In particular, the emergence of livestreaming camera technology has made recording remote video of wild and secretive animals much easier and made it possible to collect data at extremely fine temporal resolutions. In 2024, Project RattleCam launched a livestreaming camera at a Prairie Rattlesnake (Crotalus viridis) den in Colorado. The goal of this work was to study Prairie Rattlesnake behavior 24-7 throughout the species’ active season with minimal human disturbance. Additionally, I used this system to study the …

Investigating Rattlesnake Social Networks And Improving Their Public Image Through Unobtrusive Technologies And Community Science, Owen M. Bachhuber

Master's Theses

While technology is often blamed for humans’ increasing disconnect with nature, it can also serve as a tool to facilitate empathy and conservation action for wildlife. Snakes are among the most feared animals on the planet, though their understudied social interactions provide opportunities to make scientific discoveries and change public perceptions. Project RattleCam was founded as a camera trap project in 2021 and launched the first off-grid livestream on a den of wild Prairie Rattlesnakes (Crotalus viridis) in 2024. Both camera types captured hundreds of Prairie Rattlesnakes gathering in the summer as they prepared to give birth to pups before …

An Interpretative Phenomenological Analysis Of Black Female Swimmers' Experiences Of Belonging, Felicity E. Passon

Master's Theses

Although swimming participation has grown in the United States, the experiences of Black female swimmers remain significantly underrepresented in academic literature. This study addresses that gap by exploring the lived experiences of Black women participating in Division 1 (D1) college swimming. Using Interpretative Phenomenological Analysis (IPA) and Black feminist thought, the research explored how Black female D1 swimmers experienced belonging in this underrepresented sport. Semi-structured interviews were conducted with nine D1 Black female swimmers, and six major themes illustrate the varied factors that shaped their experiences of belonging. Even with racially gendered barriers to inclusion, they identified strategies to foster …

Regulation Of Spermatogenesis By The Notch Signaling Pathway, Emma O'Flaherty

Master's Theses

The Notch signaling pathway plays a significant role in gonad development and spermatogenesis, but little is known about its specific targets in the testis. The Drosophila testis contains two populations of stem cells: germline stem cells and cyst stem cells, which give rise to differentiating germline and somatic cyst cells, respectively. Notch signaling is activated in the somatic cyst cells by the Delta ligand from the germline in a region of the testes coined the “transition zone”, where somatic cyst cells progress from early cyst cells surrounding gonialblasts and 2-cell germline cysts to late cyst cells surrounding 16-cell spermatocyte cysts. …

Anthropogenic Litter In Freshwater Ecosystems: Effect On Ecosystem Processes And Spatial Distribution, Emily Johnson

Master's Theses

The rapid increase of plastic production and disposal into the environment has resulted in anthropogenic litter (i.e., trash; AL) becoming a global problem. In aquatic ecosystems, macro- and microplastics are long-lived, mobile, and interact with the physical and chemical components of aquatic ecosystems. Our objectives were to: (1) assess the impact of microplastic pollution on the ecosystem processes of ecosystem metabolism and N2 flux in an oligotrophic lake and (2) to assess the abundance and assemblage of anthropogenic litter in a large urban river. For objective (1), we added microplastics at a range of concentrations to littoral mesocosms. Ecosystem metabolism …

A Novel Approach To Treat Trastuzumab Resistant Her2+ Breast Cancer: Activation Pkcδ, Maria Grazia Mejia Monroy

Master's Theses

In the United States, approximately one in eight women will be diagnosed with invasive breast cancer in her lifetime and one in forty will die from breast cancer. From among all the different subtypes of breast cancer, HER2+ can be found in approximately 20% of breast cancer tumors. HER2 overexpression has been associated with an aggressive form of breast cancer, increasing the risk of metastasis or recurrent tumors in 50% of patients. The standard of care for HER2 positive breast cancer, trastuzumab, has been effective for some patients; however, others develop resistance over time, leading to disease progression and metastasis. …

Smart Glove Pitch Type Discrepancy Detection Algorithm For Youth And Collegiate Baseball Pitchers, Ethan B. Hemmerlin

Master's Theses

Pitch tipping refers to unintentional variations in a pitcher’s motion that reveal the pitch type, often due to inconsistent arm speed when throwing off-speed pitches like changeups. This issue is common in youth players with underdeveloped mechanics and makes it easier for batters to predict pitches. Wearable sensors, such as Inertial Measurement Units (IMUs), provide a non-invasive way to quantify these subtle motion discrepancies. This study analyzed linear acceleration data from a glove arm IMU for 14 pitchers, evenly split between high school-aged (13-15 years) and college-aged (18-23 years) groups. The aim was to examine the linear accelerations of the …

Effects Of Spirulina And Nannochloropsis Supplementations On The Meat Quality And Sensory Properties Of Broiler Carcasses, Shreyash S. Patel

Master's Theses

Microalgae are a promising feed ingredient due to their high content of proteins, lipids, polysaccharides, vitamins, pigments, and enzymes. This study evaluated the effects of algae as a dietary supplementation on the appearance, quality, and sensory attributes of broiler carcasses. In each of experiment I and II, a total of 54 Ross-708 broilers were randomly obtained from the pool of 270 broilers in the 18 floor pens of soybean-mealbased diets at 0, 2.5%, and 5% Spirulina (Experiment I) and Nannochloropsis (Experiment II) supplements in the Poultry Unit at California Polytechnic State University (Cal Poly, San Luis Obispo, CA). Broiler carcasses …

Understanding The Habitat Associations Of Nearshore Rockfishes Inside And Outside Of Marine Protected Areas Using Hook-And-Line Data, Kaila Raeanne Fritch

Master's Theses

Habitat is an important driver in shaping the distribution of a range of species. For demersal fish species, benthic habitat characteristics can drive distribution and community structure. Understanding the relationship between habitat and species distribution in important, especially for exploited species such as rockfishes (Sebastes spp.). Increased data on the relationship between rockfish and benthic habitat characteristics could enhance marine protected areas (MPAs) and management practices which are used to protect rockfishes along the U.S. West Coast. To address this, we used hook-and-line, catch-and-release data that were collected inside two MPAs on the central coast of California, and …

The Effect Of Whole Fruits High In Anthocyanins On Markers Of Glycemic Control In Women, Sophia C. Johnson

Master's Theses

Cardiometabolic diseases are a significant health burden worldwide and remain the leading cause of death among adults in the United States. Type 2 diabetes mellitus (T2DM) is a central component of cardiometabolic dysfunction and substantially increases the risk for cardiovascular disease. As women enter the post-menopausal period, significant declines in estrogen levels lead to a heightened risk of T2DM in this population. Observational and experimental evidence has shown potential for fruits high in anthocyanins (ACs) to reduce the risk of T2DM and improve glycemic control. This systematic review and meta-analysis examined the current research on whole fruits high in ACs …

Subalpine And Alpine Plant Community Turnover In Yosemite National Park Following 30 Years Of Climate Warming, Rachel Friesen

Master's Theses

Subalpine and alpine regions in California are warming more rapidly than lower elevations. In response, high-elevation plants may acclimate or adapt to the new climate, move to higher elevations or latitudes, persist in refugia, or go extinct. While models predict substantial declines in subalpine and alpine plant communities due to discontinuous population distributions and lack of upslope area, actual responses may vary due to lags in dispersal, establishment, and extinction. Although shifts in high-elevation plant communities have been documented in other regions of the world, such changes have not yet been studied in Yosemite National Park. To assess high-elevation plant …

When Trees Disappear: Understory Successional Implications Of Sudden Oak Death And High-Severity Wildfire In Big Sur, California, Sam J. Balthazard

Master's Theses

The rapidly emerging disease sudden oak death, caused by the non-native pathogen Phytophthora ramorum, is transforming coastal California forests by driving extensive mortality of tanoak (Notholithocarpus densiflorus) and increasing fire severity. As a novel disturbance, sudden oak death and its interaction with wildfire may catalyze unexpected shifts in successional trajectories and reconfigure forest understory communities. Furthermore, how tanoak influences the forest understory and how its decline might reshape understory dynamics remain poorly understood. We hypothesize that disease alone and the compounding disturbances of disease and wildfire alter successional dynamics, and that the potential functional extinction of N. …

Topodino: Self-Supervised Topological Representation Learning For Neuronal Morphologies, Yasser Binbisher

Master's Theses

Neuronal cell types are categorized by transcriptomic identity, yet their morphological heterogeneity defies this classification. In response, researchers have adopted unsupervised graph representation learning as a tool to reveal morphological variation within single-class transcriptomic types. However, the complex geometry of neuronal morphology—especially long axons and dense dendrites—challenges graph neural networks, which struggle with message propagation across extended structures. To mitigate this, current approaches enforce sub-sampling on neuronal graphs and omit axons entirely, sacrificing critical biological features for computational efficiency. To overcome this trade-off, this thesis introduces TopoDINO, a self-supervised, topology-aware representation learning model designed to preserve the full hierarchical organization …

"The Effect Of Methylobacterium Symbioticum On The Growth And Yield Of Dent Corn And Romaine Lettuce", Sinead Carney

Master's Theses

Nitrogen (N) is an essential nutrient for plant growth and is often a limiting nutrient in cropping systems. An estimated half of applied N fertilizers are lost from cropping systems by processes that can be environmentally destructive, such as leaching and volatilization, and cause economic loss for growers. Effective N biofertilizers offer a means to mitigate the need for high inputs of synthetic N. The objectives of this study were to determine the effects of leaf inoculation with the N-fixing bacteria, Methylobacterium symbioticum, in combination with different rates of urea-N fertilizer on the physiology and yield of dent corn …

Stability Insights From Modeling Chronic Myelogenous Leukemia, Giovani Thai

Master's Theses

This thesis centers around a model for chronic myelogenous leukemia (CML) as it behaves under imatinib treatment, a common medication for CML patients, and the anti-leukemia immune response. The dynamics are represented with a system of nonlinear delay-differential equations first constructed by Kim et al. in 2008, capturing population changes of T-cells and various CML growth stages. We investigate stability in both the clinical and mathematical sense. Through numerical simulations, we computationally incorporate a supplementary treatment plan to determine its effectiveness in aiding immune response and medication in achieving remission and full elimination. The primary goal is to conduct a …

Optimization Of Downy Mildew Management And Baby Kale Production On The Central Coast Of California, Emily M. Locke-Paddon

Master's Theses

Baby kale (Brassica oleracea and other species) is a vital commodity as a salad green in spring mix and is widely produced on the Central Coast of California. Downy mildew, caused by Hyaloperonospora brassicae, is a devastating disease infecting economically important crops like cabbage, broccoli, cauliflower, horseradish, rapeseed, kohlrabi, Brussels sprouts, and kale. This foliar disease causes plant tissue to exhibit chlorotic and necrotic flecking and gray-white sporulation, affecting both the yield and quality of the crop and rendering the affected leaves unmarketable. The Central Coast’s cool climate and nighttime moisture, combined with dense plantings and sprinkler irrigation, …

Identifying Interchromosomal Interactions Using A Graph-Based Computational Pipeline, Ethan Outangoun

Master's Theses

Current computational tools for analyzing chromatin organization are mainly focused on intrachromosomal interactions, despite growing evidence that suggests long-range interactions across chromosomes contribute to transcriptional regulation and disease development. This thesis aims to address this gap in interchromosomal genome analysis, presenting a robust computational pipeline that identifies a clique (i.e., a subgraph) of highly interacting trans-chromosomal regions anchored at a user-specified seed genomic locus. A weighted interaction network is constructed from an input Hi-C contact matrix, a widely used experimental assay for measuring genome-wide chromatin interactions. We model this input contact matrix as a graph and devise three different strategies …

Correlations Between Social Media, Body Image Perceptions, And Disordered Eating Prevalence In Postpartum Women: A Pilot Cross-Sectional Study, Hannah Smith

Master's Theses

Postpartum women are a high-risk population for body dissatisfaction and disordered eating behavior due in part to the plethora of hormonal and physiological changes. Despite this, research examining this issue among postpartum women remains limited.

This pilot cross-sectional study investigated the relationship between social media use, body dissatisfaction, and disordered eating behavior among women up to 13 months postpartum. For this study, the following research questions were asked: Is high social media usage associated with higher levels of disordered eating among women up to 13 months postpartum? Is the association between social media usage and disordered eating mediated by a …

Evaluating Nanobubble-Enriched Water Treatments For Cleaning Stainless Steel Winery Tanks At The Gallo Winery Research Station In Livingston, California, Edgar Godoy-Garcia

Master's Theses

ABSTRACT

Evaluating nanobubble-enriched water treatments for cleaning stainless steel winery tanks at the Gallo winery research station in Livingston, California.

Edgar A. Godoy-Garcia

Sanitation of stainless steel wine storage tanks is a critical component of quality control in commercial winemaking operations. Ineffective cleaning can lead to microbial contamination, product spoilage, and safety concerns. Traditionally, wineries rely on manual scrubbing, chemical cleaning agents, and extensive water rinsing cycles to maintain sanitary tank conditions. However, these methods are resource-intensive and may pose risks to both workers and the environment due to chemical exposure and wastewater generation. In response to growing industry interest …

The Effects Of Sirulina And Nannochloropsis Supplementation On Broiler Performance, Intestinal Morphology, And Gut Microbiology, Emily Beckerman

Master's Theses

The poultry industry is constantly searching for new nutritional strategies and better feed conversion ratio to enhance broiler growth and productivity. Microalgae have been shown to improve broiler performance and health depending on species and supplementation levels. The objective of this study was to determine the effects of Spirulina supplementation (Experiment I) and Nannochloropsis supplementation (Experiment II) on broiler production performance, intestinal morphology, and gut microbiology. In Experiment I, a total of 270 broiler chicks (one-day-old Ross 708) were obtained from a local hatchery after vaccinating against Newcastle, Marek’s disease, and Infectious Bronchitis. They were weighed and sorted into 18 …

The Impact Of Growth Hormone-Releasing Hormone Antagonist On Human Adipose-Derived Stem Cells, Jeanne Michelle Dugas

Master's Theses

Obesity is a condition that affects over 40% of American adults and contributes to numerous preventable health issues. This condition is caused by increased adipose tissue, which forms when stem cells transform into adipocytes. Mesenchymal stem cells, including human adipose-derived stem cells (hASC), are multipotent with the ability to differentiate into adipocytes, osteocytes, or chondrocytes. Many factors affect this transformation, including the peptide growth hormone-releasing hormone (GHRH). The main role of GHRH is to trigger the release of growth hormone, but it has also been found to play an important role in adipocyte metabolism. We expect that if the differentiation …

The Antioxidant Potential Of Rosemary Leaf-Derived Nanovesicles, Shani Akila Griffin

Master's Theses

Human dermal fibroblasts are essential for maintaining skin homeostasis. However, exposure to exogenous and endogenous stressors can lead to fibroblast instability, extracellular matrix degradation, and excessive reactive oxygen species (ROS) production. These factors contribute to skin aging and ROS-induced skin disorders leading to hair loss. Adverse effects from synthetic treatments have driven interest in natural alternatives like plant extracts for skin therapy. However, the polyphenols in these treatments require an effective delivery system to ensure their stability and targeted application. Plant derived nanovesicles (PDNVs) are emerging as a promising natural alternative for therapeutic applications. Their biocompatibility, stability, and encapsulated compounds …

Pollinator Plant Communities Within Restored Montane Longleaf Pine Ecosystems, Hanen Van Rossem

Master's Theses

Historically the fire-dependent and biodiverse longleaf pine (Pinus palustris) ecosystem was the dominant ecosystem of the Southeastern US. This ecosystem’s range was massively reduced due to land conversion and fire exclusion, causing the decline of many native species. Efforts to restore and protect longleaf pine stands are now ongoing with the goal of expanding habitat and refuge for threatened species. Differences in restoration practices and prior land use may influence the extent to which restored habitat patches can support pollinators and their plants. This study compared pollinator plant biodiversity between restored neighboring montane longleaf pine stands that differed in …

Identification Of Methylation Patterns, Associated Dna Methylating Proteins, And Methyltransferase Inhibitors On The Promoter Regions Of Dax-1, Brandon Tyler Toy

Master's Theses

The DAX-1 gene (Dosage-Sensitive Sex Reversal, Adrenal Hypoplasia Congenita, Critical Region on the X chromosome, gene 1) encodes for an orphan nuclear hormone receptor and its mutation is implicated in multiple diseases including congenital adrenal hypoplasia, adrenal cancer, and breast cancer. Previous research has linked DAX-1 downregulation to tumor initiation in breast tissue, suggesting the gene acts as a tumor suppressor with respect to breast cancer. Additional studies completed by the Tzagarakis-Foster laboratory have shown that methylation of the DAX-1 promoter region is heavily influential in breast cancer development, with release of epigenetic repression resulting in slowing of cellular proliferation …

Agreement Between Methods For Describing The Intensity Of A High Intensity Functional Training Workout, James W. Henley

Master's Theses

This study examined whether a speed-based metric, expressed as percent of maximal speed (%MS), could serve as a practical and accurate method for quantifying intensity in high-intensity functional training (HIFT). Traditional intensity markers—heart rate (HR), blood lactate concentration ([La-]), and rating of perceived exertion (RPE)—were compared to %MS during low- and high-volume (LV, HV) workouts using a combination of correlation and agreement analyses. Twelve males and twelve females completed a baseline assessment followed by two experimental workout sessions. Participants wore HR monitors, provided pre- and post-exercise [La-] samples and RPE scores, and performed maximal speed tests for each workout movement. …

Does Limb Specialization In Track And Field Introduce Asymmetry In Dynamic Stability?, Aaron X. Jones

Master's Theses

Time to stabilization (TTS) represents the time it takes for a person to become still after a hop landing. Lower times suggest greater dynamic stability. Whereas leg dominance (preference) does not seem to have a significant impact on TTS performance in the general healthy populations, limb specialization in sport may introduce asymmetry. This study compares TTS following forward hops in healthy male controls (N = 19) to varsity DIII Track & Field athletes (N = 20). Groups were equal for height, but the athlete group’s average limb length (106.7 ± 5.5 cm) was greater than the control group (101.5 ± …