Life Sciences Commons^™

Morphological Variation Of Lingual Glands In Wild American Alligator (Alligator Mississippiensis) Populations, Benjamin Angalet

Master's Theses

American alligators (Alligator mississippiensis) inhabit diverse aquatic ecosystems including freshwater wetlands, swamps, and estuarine rivers. As apex predators, their physiological resilience has implications for ecosystem stability and long-term conservation. With projected sea-level rise and increasing saltwater intrusion into coastal freshwater habitats, understanding the osmoregulatory capacity of alligators is increasingly important. Unlike marine-tolerant crocodilians such as the saltwater crocodile (Crocodylus porosus), which possess specialized salt-secreting lingual glands in addition to renal and cloacal mechanisms, the morphology and physiological significance of lingual glands in wild American alligators remain poorly understood. This study examined lingual gland morphology and plasma …

The Impact Of High-Cadence Cycling On Overground Running Performance In Recreational Runners, Matthew Ott

Master's Theses

Cycling is a commonly used exercise because it provides a controllable cardiovascular and musculoskeletal demand while imposing relatively low impact on the rider. High-cadence cycling (HCC) has been shown to influence subsequent running performance and gait performance by increasing cadence and reducing work rate when cycling prior to running. However, most of this work has focused on triathletes and older adults. Therefore, the purpose of this study was to examine the acute effects of HCC on subsequent 800 m running performance and spatiotemporal parameters in adult recreational runners. Thirty recreational runners completed two testing sessions. On Day 1, participants performed …

Discerning Patterns Of Floral Sugar-Feeding: Dynamics Of The Mosquito Culex Antillummagnorum In Puerto Rico, Ella J. Branham

Master's Theses

Mosquitoes rely on sugar feeding for survival, primarily from flowering plants, yet mosquito–plant interactions remain understudied. I examined plant-feeding associations of the mosquito Culex antillummagnorum in the Luquillo Experimental Forest of Puerto Rico, which may clarify patterns of habitat use, disease dynamics, and broader species interactions. First, plant DNA was extracted from field-collected Cx. antillummagnorum to identify potential nectar sources. DNA barcoding produced positive matches to the flowering plant genera Billia, Aesculus, Cladium, Fimbristylis, Xyris, Cakile, and Habenaria. Habenaria was the most compelling result because it belongs to the same subtribe of orchids …

Redeveloping Mississippi: A Case Study On Brownfields In Central & Southern Mississippi, Sahrah R. Yeroozedek

Master's Theses

Brownfields, or properties that are or possibly are contaminated with dangerous materials, represent a common obstacle for communities in Mississippi. The real or potential presence of contaminants at these sites often deters investors due to costly cleanup requirements (EPA, n.d. -b). The Environmental Protection Agency (EPA), through its Brownfield Revitalization Program, implemented guidelines for covering the costs and labor associated with the remediation of these properties. The EPA is not, however, responsible for redevelopment that supports long-term environmental and economic sustainability. Although the EPA maintains inventories of all Brownfields, there is also no comprehensive database of Brownfields and their current …

The Application, Construction, And Validation Of Hidden Markov Model Profiles For Carbonic Anhydrase Enzymes, Samuel F. Kaplan

Master's Theses

Carbonic anhydrases (CAs) catalyze the reversible hydration of CO2 and have evolved independently at least eight times, resulting in structurally distinct enzyme families (α, β, γ, δ, ζ, η, θ, ι). Traditional sequence alignment methods struggle to classify these convergently evolved proteins because their sequential similarity does not reliably indicate functional or evolutionary relationships. Many CA sequences in public databases are annotated generically without family assignments, and prior computational approaches have focused predominantly on the three well characterized families (α, β, γ), leaving the five recently discovered classes without robust classification tools. Family level assignment is often a prerequisite for …

Exploring Non-Conventional Substrates: The Role Of Hibiscus And Whey In Kombucha Fermentation, Benjamin J. Lee

Master's Theses

This study evaluated the impact of hibiscus and whey as alternative fermentation substrates on the physicochemical, phytochemical, and microbial properties of kombucha. A 2 × 2 full factorial design was used to compare four treatments: black tea + water (BW), black tea + whey (BH), hibiscus + water (HW), and hibiscus + whey (HH). The fermentation solvents (water or whey) were heated to 88 °C, infused with 0.6% (w/v) black tea or hibiscus for 10 minutes, sweetened with 10% (w/v) sucrose, cooled to 22 °C, and inoculated with 20% (v/v) kombucha starter culture. Fermentations were carried out at 22 °C …

Measurement And Control Of The Oxidation-Reduction Potential And Its Chemical And Sensory Consequences In Wines, William Jordan Wright

Master's Theses

The oxidation-reduction potential (ORP) is a measurement thought to reflect the overall ability of a solution to oxidize or reduce substances within that solution. In wine, there is no absolute agreement as to which substances control or dominate the ORP; however, oxygen, ethanol, iron-tartrate and copper-tartrate complexes, and glutathione are suspected to play key roles, while sulfur dioxide and phenolics may act as buffers. Anecdotally, some varieties of Vitis vinifera are prone to oxidation while others are prone to reduction, though the chemical basis of this remains unclear. The following works aim to further elucidate the influence of specific chemical …

Associations Between Nutrition-Related Chronic Disease And Food Insecurity: Data From The California State University, Elizabeth Ochoa

Master's Theses

Food insecurity is a growing public health concern consistently associated with elevated rates of nutrition-related chronic disease (NRCD) across the general population. Despite young adulthood being a critical window for dietary pattern formation, this relationship remains minimally explored among college students. This thesis examined associations between food insecurity and NRCD diagnosis, including hypertension, diabetes, hyperlipidemia, and cardiovascular disease, among undergraduate students across the California State University (CSU) system. Cross-sectional data were drawn from the Spring 2021 CSU National College Health Assessment, administered across all 23 campuses. After exclusions, the analytical sample comprised 13,762 students. Bivariate analyses assessed relationships between key …

Birds In Changing Landscapes: Community Diversity And Breeding Phenology, Lindsay Peria

Master's Theses

Humans are altering the environment in varied and widespread ways. Increasing urban and agricultural development causes changes to habitat and resource availability as well as changes to the sensory environment via light and noise pollution. Climate change also causes more extreme temperature anomalies, storms, and droughts that challenge birds in a multitude of ways. In this thesis, we assessed these impacts of these changes on a local and continental scale. In the first chapter, we assessed the impact of natural, anthropic, and structural characteristics of viticultural land on both taxonomic and structural avian diversity. Loss of habitat from agriculture is …

Associations Between Feed Efficiency And Feeding Behavior In Yearling Angus Bulls In A Competitive Environment, Amelia Katz

Master's Theses

Feed efficiency in beef cattle is a complex trait shaped by physiological, behavioral, and social factors that influence how animals access and utilize feed resources. This study examined feed efficiency classification and how it is influenced by feeding behavior, competitive interactions, and bunk approach patterns in yearling Angus bulls housed in a drylot over two years. Bulls were grouped into high and low feed efficiency categories using residual feed intake and feed conversion ratio within pen and year (n = 40 per year; n = 40 per treatment). Continuous electronic monitoring quantified feeder visitation, feeding duration, intake, and rate. A …

Performance Enhancement For Rufa: Rapid Urban Forest Assessment, Nicholas Tan

Master's Theses

Urban forests are crucial to the livability and resilience of cities, offering critical ecosystem benefits such as air quality enhancement, temperature regulation, and biodiversity. Managing said urban forests is essential to ensure their sustainability and adaptability to rapidly changing environmental and climate conditions. The Rapid Urban Forest Assessment (RUFA) tool was developed to address the need for a standardized approach to evaluating and comparing urban and community forestry programs. By analyzing and aggregating tree-specific data across California, such as canopy cover, tree counts, and diversity scores, RUFA assigns a comprehensive urban forestry score for each city. This score allows for …

Flower Color Variation And Its Maintenance: Experimental Ecology Of Serpentine-Adapted Leptosiphon Parviflorus Benth. (Polemoniaceae), Magdalene S. Lo

Master's Theses

Environmental heterogeneity can impose fluctuating selection pressures on species across space and time. If variations of a trait provide fitness benefits in certain environmental conditions but not others, these fitness tradeoffs under fluctuating selection could be a means of maintaining intraspecific variation. A common type of intraspecific variation is the production of anthocyanins, pigments responsible for red, pink, and blue colors in plants and that can also provide protection from abiotic stressors, such as water limitation and heavy metals. Leptosiphon parviflorus Benth. (Polemoniaceae, variable linanthus) is an annual wildflower whose individuals produce either pink or white flowers, and both flower …

Abiotic Stress Impacts On Macrophomina Root Rot And Nano-Encapsulated Citrus Oils To Control Fruit And Foliar Pathogens Of Strawberry, Marina J. Gutierrez

Master's Theses

Disease remains one of the major constraints to the productivity and economic success of the California strawberry industry. The most important soilborne pathogen is Macrophomina phaseolina, causing Macrophomina root rot (MRR). The most economically significant airborne pathogens include Botrytis cinerea, causing Botrytis fruit rot (BFR), and Podosphaera aphanis, causing powdery mildew (PM).

Disease severity of MRR is highly dependent on environmental factors. Therefore, understanding which abiotic stressors contribute most to disease development is crucial for effective management. A two-year field experiment at Cal Poly, SLO (2024 and 2025) evaluated the effects of drought stress, two elevated chloride …

Associations Between Food Insecurity And Gpa Among Full-Time California State University Undergraduates During Covid-19: The Impact Of Mental Health, Lindsey Jones

Master's Theses

Food insecurity is a persistent public health concern among college students that has been associated with student’s academic and mental health outcomes. This thesis examined the associations between food insecurity, academic performance (measured by GPA) and mental health (using Kessler 6 psychological distress and self-perceived mental health impacts on academic performance), among full-time undergraduate students within the California State University (CSU) system. Cross-sectional analyses were conducted using data from the Spring 2021 CSU National College Health Assessment, administered across all 23 campuses. Of the 20,167 respondents, 12,899 students were included in the analytical sample. Bivariate analyses were conducted to analyze …

Why The Long Face? The Distribution And Niche Of The Imperiled Narrow-Faced Kangaroo Rat (Dipodomys Venustus), Garrett L. Gimbel

Master's Theses

Distribution models provide a practical use case of connecting ecological niche theory with species’ occurrence and assemblages. By explicitly linking Hutchinson’s “niche space” with geographic space researchers can gain valuable information on a species’ niche characteristics and interactions, thereby informing conservation and management practices. The narrow-faced kangaroo rat (Dipodomys venustus) is a highly understudied kangaroo rat species endemic to the central coast of California and is an ideal species to explore niche theory in distribution modeling. Three subspecies are currently recognized: The Santa Cruz kangaroo rat (D. v. venustus), the elephant-eared kangaroo rat (D. v. …

Differences In Loading Rate In Shod And Unshod Treadmill Walking, David Austin Kropushek

Master's Theses

The purpose of this study was to compare the loading rates of shod and unshod conditions in treadmill walking. It was hypothesized that walking barefoot would demonstrate higher loading rates than walking with shoes. It was also hypothesized that walking barefoot on a treadmill would result in greater stride-to-stride variability than walking with shoes. Sixteen healthy adult females volunteered and provided their consent to participate in this study. Participants were given time to accommodate to the instrumented treadmill both while wearing shoes and without. Two 10-minute trials were collected with a rest period between. Data were analyzed using Vicon Nexus …

Seagrass Carbon Standing Stock In The Northern Gulf Of Mexico: The Role Of Seagrass Beds In Mississippi As Potential Blue Carbon Sinks, Devan Hildebrand

Master's Theses

Organic carbon stored in marine ecosystems is known as blue carbon. Seagrass beds have the ability to contribute to global blue carbon standing stocks through the uptake and sequestration of carbon from the water column. Through coastal management and conservation best practices, blue carbon habitats have the potential to help mitigate the effects of climate change. Although widely studied, knowledge gaps exist on the sediment carbon standing stock of seagrasses. I aim to better understand how persistent seagrass meadows surrounding barrier islands in the northcentral Gulf of Mexico contribute to long-term blue carbon standing stocks. Subaqueous sediment cores were collected …

Life History And Distribution Of Two Species Of Cownose Ray, Rhinoptera Bonasus And Rhinoptera Brasiliensis, In Mississippi Coastal Waters, Anna Millender

Master's Theses

Historically, the American Cownose Ray (Rhinoptera bonasus) was considered the only rhinopterid residing in the northern Gulf of Mexico (GOM); however, recent studies have confirmed the presence of the Brazilian Cownose Ray (Rhinoptera brasiliensis) throughout this region. The current study investigated the life history and distribution of both species within Mississippi waters, an area that previously represented a data gap for both species. From April 2016 – July 2025, 193 R. bonasus and 94 R. brasiliensis were analyzed to describe the reproductive biology. Reproductive timing, mating, gestation length, and parturition were similar among species. Although more …

Isolation Of The 2019 Bonnet Carré Spillway Effects On The Habitat Suitability Of Brown Shrimp (Farfantepenaeus Aztecus) And Blue Crab (Callinectes Sapidus) Using A Modeling Approach, Mallory Dyson

Master's Theses

In 2019, an unprecedented flood year, the Bonnet Carré Spillway (BCS) was opened on two separate occasions (February 27^th to April 11^th, and May 10^th through July 27^th) diverting a volume 6 times the volume of Lake Pontchartrain into the surrounding coastal waters of Louisiana, Mississippi, and Alabama. The goal of this research was to determine the spatio-temporal influence of these freshwater releases on two economically and ecologically important species (Farfantepenaeus aztecus and Callinectes sapidus) with variable responses to salinity and temperature depending on the age class. The Habitat Suitability Index (HSI) …

Serum Concentrations Of Inflammatory Markers And Selected Nutrient Metabolites In Holstein And Jersey Cows Across The Transition Period, Avery Orr

Master's Theses

The transition period, spanning the weeks surrounding parturition, requires dairy cows to undergo synchronized metabolic, endocrine, and immunological adjustments that support the onset of lactation but also heighten disease susceptibility. Although individual inflammatory or metabolic biomarkers have been extensively studied, the integrated immunometabolic dynamics that occur across this period and the difference between breeds is not fully understood. The objective of this study was to characterize longitudinal patterns in key nutrient metabolites and inflammatory markers in Holstein and Jersey cows and assess how these systems interact across the transition period.

A total of 63 Holstein and Jersey cows were sampled …

Testing For Local Adaptation In Sympatric Monkeyflowers Growing In Serpentine Seeps And Adjacent Rock Outcrops, Avin Niknafs

Master's Theses

Divergent selection across heterogeneous environments can drive ecological differentiation and the evolution of locally adapted populations, even when gene flow occurs. We tested for local adaptation between two sympatric monkeyflowers, Erythranthe guttata and E. serpentinicola (formerly Mimulus), which co-occur on the central coast of California. Erythranthe guttata is a perennial species primarily found in moist serpentine seeps, whereas E. serpentinicola is an annual species restricted to adjacent serpentine rock outcrops. Using a reciprocal transplant experiment with second-generation, greenhouse-derived seed, we quantified germination, survival, and reproductive success across contrasting microhabitats. We further evaluated the relative contributions of species, lineage, …

Impacts Of Halophila Stipulacea Invasion On Organic Matter Dynamics In Thalassia Testudinum Dominated Seagrass Meadows, Puerto Rico, Jonathan D. Herald

Master's Theses

Halophila stipulacea (Forsskål & Niebuhr) is a tropical seagrass native to the Red Sea, Persian Gulf, and Indian Ocean. In 2002, invasive populations of H. stipulacea were identified in the Caribbean Sea where it now forms large meadows, displaces native seagrasses, alters invertebrate and fish communities, and potentially affects organic matter dynamics in invaded meadows. This study investigated differences in organic matter dynamics between meadows of H. stipulacea and native Thalassia testudinum within the Jobos Bay National Estuarine Research Reserve (JBNERR) on the southern coast of Puerto Rico. From March 2023-March 2024, sampling was conducted across four sites to investigate …

Effects Of Urbanization On The Population Genetics And Morphology Of The White-Footed Mouse (Peromyscus Leucopus) Across An Urban–Rural Gradient, Sydney A. Morton

Master's Theses

Urbanization alters landscapes in ways that can reshape wildlife populations by changing habitat connectivity, resource availability, and selective pressures. To investigate how urbanization influences both genetic differentiation and morphology in small mammals, I examined Peromyscus leucopus (PELE) across an urban–rural gradient in northern Georgia. Using RADseq SNP data from PELE individuals across 13 sites, I quantified pairwise genetic differentiation (F_ST) and tested how various environmental variables, including impervious surface cover, human population density, and tree canopy cover, predict genetic differentiation after accounting for geographic distance. Genetic differentiation increased with geographic distance and, after controlling for isolation by …

Phylogenetic Comparative Vocal Evolution, Casper W. Buchanan

Master's Theses

Vocal learning is a trait unique to humans, bats, cetaceans, primates, and birds (Jarvis & Nottebohm, 1997; McComb & Semple, 2005; Wilbrecht & Nottebohm, 2003). Although there has been extensive research on vocal learning in songbirds, parrots are an even closer proxy to human learning, as they are social, intelligent, and lifelong learners, with some having repertoires of over 300 sounds (Benedict et al., 2022; Péron et al., 2011; Thomsen et al., 2019; Toft & Wright, 2015). Elevated vocal learning can be attributed to the need for parrots to have strong communication skills through the sharing of information over foraging, …

Dietary Intake And Changes In Body Composition Over The Course Of One Season In Ncaa Division 1 Football Players, Blayke W. Harrison

Master's Theses

Energy intake and macronutrient composition of an athlete’s diet is highly important when considering performance. Additionally, having a favorable body composition (i.e. low levels of fat mass and high levels of lean body mass) is crucial in high-level athletes.The role of nutrition-related support personnel is highly needed by many collegiate athletics programs to achieve these outcomes, yet this resource seems to be undervalued and underused in many settings. The present thesis investigates the effects of providing nutritional support to improve dietary habits and compare changes in specific body composition metrics over the course of one season (pre- and post-season) among …

Gene Expression Of Anthocyanin Pigments In The California Native Plant Leptosiphon Parviflorus: Interactions Between Flower Color Morphology And Abiotic Stressors, Weston Gonor

Master's Theses

For plants to survive in harsh conditions imposed by abiotic stressors, they must develop mechanisms of adaptation. One of the common types of adaptation seen in plants is the production of anthocyanin pigments, which have been shown to protect plants from UV radiation, metabolic stress, and drought. In this study, we used the flower color polymorphic species Leptosiphon parviflorus to investigate the role of anthocyanin pigments in protecting plants from abiotic stress. To accomplish this, RNA samples were taken from flower, leaf and root tissue of different flower color morphs of Leptosiphon parviflorus (Polemoniaceae) grown in high magnesium and water …

Alpine Plants And Climate Change: Tracking Community Shifts In Yosemite National, Brooke L. Wallasch

Master's Theses

As climate change progresses, alpine plant communities are predicted to shift upslope as they track temperature over time. Relative to lowland environments, alpine areas are experiencing a faster rate of temperature change due to a phenomenon referred to as elevation-dependent warming. A common approach for tracking plant communities shifts over time, is to conduct resurveys of the same area at several time points, as the Global Observational Research Initiative in Alpine Environments (GLORIA) has done on mountain summits around the world since 2001. In 2011-2013, GLORIA developed a supplemental survey method whereby belt transects were established downslope of summits in …

Enhancing Preparedness: A Genetic Study Of Sar-Cov-2 And Other Microbial Public Health Threats In Wastewater From A College Town, Christian N. Hutchinson

Master's Theses

Problem

The SARS-CoV-2 (COVID-19) pandemic revealed both the systemic vulnerabilities of our healthcare system as well as the importance of timely, localized data for informing public health responses. Traditional testing approaches were essential but often failed to capture the full extent of viral spread, especially in those with mild or asymptomatic conditions that relied on at home testing. This underreporting hindered effective allocation of resources and made developing effective intervention strategies difficult. We also realized the potential for wastewater surveillance to be applied to tracking antimicrobial resistance gene markers. Taken together, this approach should have important implications for improving public …

Demographic Characteristics And Selected Personality Traits Of Women In Competitive Bodybuilding, Chloe A. Zeeuw

Master's Theses

This study investigated demographic characteristics and measures of personality (dimensions of performance perfectionism and five-factor model characteristics) in women in competitive bodybuilding between 18-25 years old. A total of 24 women completed an online survey which included a demographic questionnaire, the Five Factor Model Rating Form (FFMRF), and the Performance Perfectionism Scale for Sport (PPSS) inventories. Descriptive results for the FFMRF were Openness (18.17±3.12), Conscientiousness (25.58±3.33), Extraversion (19.96±3.46), Agreeableness (19.88±4.58), and Neuroticism (15.67±4.94), and for the PPS-S were Self-oriented performance perfectionism (20.96±3.53), Socially prescribed performance perfectionism (13.96±4.26), and Other-oriented performance perfectionism (10.54±4.23). Pearson’s correlation coefficients and Shapiro-Wilk tests revealed that …

A Pilot Study Exploring Vitamin D, Mental Health, And Gastrointestinal Health In Humans, Brianna C. Williams

Master's Theses

Mental disorders are experienced by nearly one billion people worldwide. Depression is one of the most common. Treatments exist, yet a devastating 75% of individuals suffering from depression do not receive adequate treatment. An emerging treatment strategy includes exploring the connection between mental health and nutrition, which includes the areas of gut health and nutrient deficiencies. Vitamin D is obtained through food, supplements, and sunlight. Many individuals are considered deficient (25[OH]D concentrations < 12 ng/mL) or insufficient (25[OH]D concentrations < 20 ng/mL). Purpose: This study aimed to explore mental and gastrointestinal (GI) health using surveys and lipopolysaccharide binding protein (LBP) concentrations, a biomarker of GI health, in individuals considered 25(OH)D deficient (DEF) vs not deficient (N-DEF). Methods: This cross-sectional study recruited physically active participants aged 18-45 years who underwent three evaluations in one visit. Health was assessed using surveys to evaluate mental health, GI symptoms, and vitamin D intake. Serum from fasting blood samples was used with an enzyme-linked immunosorbent assay to determine 25(OH)D and LBP concentrations. Unpaired t-tests were used to compare DEF vs N-DEF and significance was set at p < 0.05. Results: Thirty-two participants (mean age 25.3 ± 6.3 years) with mean and body fat percentage of 24.0% ± 10.7%, were placed into DEF (n=16) and N-DEF (n=16) categories. Interestingly, five of the 16 participants in DEF (31%) showed some level of depression (scores ranging from mild to severe) and only two of the 16 participants in N-DEF iv (13%) scored positively in the depression category (scores ranging from mild to moderate). Additionally, the participant with the lowest 25(OH)D concentration (5.42 ng/mL) was the only participant to meet the “severe” depression category criteria, with a score of 24 compared to other participants who scored within 0-16. Also, the only participant who scored “severe” in the stress category, was in the bottom 20% of 25(OH)D concentrations. As for GI health, the difference between average GI scores and average serum LBP concentrations between the groups were not statistically significant. Conclusion: There were no significant differences between DEF and N-DEF in perceived depression (p = 0.16), anxiety (p = 1.0), stress (p = 0.96), GI symptoms (P values ranged from 0.27 to 1.00), nor in LBP concentrations (p = 0.77). Funding: Support was received from the Graduate Student Association and College of Natural Health Sciences at the University of Northern Colorado.