Digital Commons Network^™

California Utility-Scale Solar Energy Land Use Impacts On Species And Ecosystems, Ingrid Salazar

Master's Theses

Utility-scale solar energy (USSE), defined as projects of at least 1 megawatt, is rapidly expanding in California, which generated 37.5% of its electricity from renewables in 2023, with 24% coming from solar. While USSE supports decarbonization, it can also cause environmental harm, including biodiversity loss, habitat fragmentation, and land conversion. This study uses ArcGIS Pro 3.4.0 and public environmental data to analyze the spatial distribution of USSE projects, land use changes from 2013 to 2023, and occurrences of at-risk species across California’s bioregions. USSE development is heavily concentrated in the Mojave Desert, San Joaquin Valley, and Colorado Desert, which are …

Riparian Restoration Increases Soil Microbial Biomass In Marin County Rangelands, But Soil Carbon Stock Is Less Responsive, Sherilyn Kathryn Reinhart

Master's Theses

Land use change has caused the degradation of 70% of the Earth’s soils, directly altering soil microbial communities and carbon cycling. Interest in carbon farming practices is growing, but studies that document the nuances of soil carbon flux in specific bioregions are still too few. In this study, I examined how one practice, riparian restoration, alters soil carbon stock and microbial community structure over time. Using a paired sampling time series design, I collected soil samples from twelve riparian forests and adjacent rangelands near Marin County, California. Young and mature sites ranged from five to 29 years since restoration, and …

Correlations Of Intersectional Identity Cohesion And Growth In Queer And Transgender Black, Indigenous, And People Of Color, Zoha T. Qader

Master's Theses

Past research has found that identity cohesion (how integrated multiple identities are) is a protective factor that moderates the relationship between intersectional microaggressions and mental health outcomes. Individuals with higher identity conflict (multiple identities clashing) had anxiety and depression symptoms that could be predicted by the distress they experienced from intersectional microaggressions. For those with high identity cohesion, this was not the case. While compelling, the question remains, what are the factors that contribute to identity integration versus identity conflict? The present study will utilize existing data of 417 QTBIPOC individuals. Ratings of LGBTQ+ community belonging and engagement, and LGBTQ+ …

Exploring The Ant: How Well Do Three Attention Networks Predict Road Hazard Perception, Xander Philip Martinez

Master's Theses

Hazard perception is the ability of a driver to anticipate emerging dangers. Driving is a complex activity requiring attention to various stimuli to prevent accidents. Prior studies have shown that older, experienced drivers detect more cues and perceive hazards better than younger, inexperienced drivers. Attention is multifaceted, and three visual attention networks were focused on in the study: alerting (readiness), orienting (spatial focus), and executive control (distraction inhibition). A sample of 95 participants completed two tasks: The Attention Network Test was used to assess these three attention networks, and to measure road hazard awareness, participants viewed short dashcam videos (~233 …

Post-Fire Succession In An Old-Growth Coast Redwood (Sequoia Sempervirens) Forest In The Santa Cruz Mountain Bioregion, Mojgan Mahdizadeh

Master's Theses

Fire is a common disturbance in the western United States, and variation in its frequency and intensity can significantly impact species recovery and distribution across ecosystems. While fire frequency and intensity are increasing in coast redwood forests, little is known about how this forest type responds to high-intensity wildfires. In 2020, a high-intensity wildfire burned large portions of the coast redwood forest in the Santa Cruz Mountains, including over 1,700 ha of old-growth. This event created a unique opportunity to evaluate post-fire succession. This research assessed vegetation recovery across high and low to moderate severity burned areas using random sampling …

The Impact Of Early Life Experiences On Math Confidence, Nhu X. Hin

Master's Theses

Students form beliefs about their academic abilities through a combination of emotional experiences and early learning environments. While prior research has documented how math anxiety can undermine performance and how early experiences with math-typed activities can foster positive attitudes, less is known about how these factors collectively influence students’ math confidence. The present study investigates how math anxiety, engagement in childhood math-typed activities, and perceived support for math-related learning contribute to college students’ confidence in their math abilities. Participants (N = 102) completed self-report measures assessing each of these constructs. A multiple regression analysis revealed that the three predictors collectively …

It Shucks To Be Inbred: Effects Of Small Population Sizes On Genomic Diversity Of Hatchery Reared Olympia Oysters (Ostrea Lurida), Anna S. Heasley

Master's Theses

Olympia oysters (Ostrea lurida), critical members of estuarine ecosystems along the California Current Ecosystem (CCE), have faced significant population declines due to historical overfishing and habitat deterioration. Today, managers from multiple estuaries across the CCE are focusing on conservation aquaculture breeding efforts to aid in restoration; however, the genetic implications of these efforts remain unexplored. As with other Ostrea spp, Olympia oysters have a viviparous reproductive strategy that creates unique challenges for aquaculture-mediated restoration. This study evaluates the genetic impact of current captive breeding practices on Olympia oyster cohorts produced in three California estuaries: Elkhorn Slough (EHS), Morro Bay (MB), …

Sea Otter Behavior And Prey Composition Across Alternative Reef States In Monterey, Ca: Applying Ecological Theory To Kelp Restoration, Carter Hawkins

Master's Theses

Due to a myriad of factors, giant kelp (Macrocystis pyrifera) abundance along the California coast has decreased in select areas, leading to the formation of lower-diversity ecosystems dominated by purple sea urchins (Strongylocentrotus purpuratus), known as “urchin barrens.” While sea otters (Enhydra lutris) are keystone predators that help maintain kelp forests through predation on sea urchins, in Monterey, they avoid barren sea urchins due to their low energetic value and abundance of other habitat types, limiting their influence in these areas. From 2021-2023, sea urchin culling at Tankers Reef, a former barren site in Monterey Bay, was conducted to promote …

The Anti-Work Attitude Scale: Conceptualizing And Measuring The Resistance To The Institution Of Work, Alayna Del Rosario

Master's Theses

Recent shifts in labor discourse have drawn attention to rising burnout, declining organizational commitment, and diminishing job satisfaction, which challenge traditional assumptions about the centrality and desirability of work. These tensions have given rise to the concept of anti-work, a growing discourse that questions the moral, economic, and psychological foundations of work itself. Despite its cultural relevance, anti-work remains largely undertheorized and unmeasured in empirical research. Drawing from interdisciplinary scholarship, this study defined anti-work as a negative critique of work as a social construct, questioning its value, purpose, and impact on individuals and society. Anti-work was operationalized through two higher-order …

The Relationship Between Hindrance Demands And Work Engagement: The Moderating Role Of Resilience, Adoré Davis

Master's Theses

The coronavirus pandemic decreased work engagement globally due to increased hindrance demands. Many organizations were motivated to increase work engagement, which is positively correlated with beneficial organizational outcomes. The intention of this study is to examine if personal resources like resilience moderate the relationship between hindrance demands and work engagement. Hindrance demands are refined from job demands and hindrance stressors, which are stressors that impede progress in employees. Resilience is a personal resource correlated with pro-social behavior, internal locus of control, and higher levels of empathy. Resilience as a personal resource has mainly been studied as a predictor of work …

Working Memory In Major Depressive Disorder: A Meta-Analysis Of Structural And Functional Brain Differences, Eunji Back

Master's Theses

Major depressive disorder (MDD) is one of the most prevalent mental health disorders in the US and is characterized by depressed mood and loss of interest. Many MDD patients also experience difficulties with executive function, including working memory. Neuroimaging studies reveal structural and functional brain differences between MDD patients and healthy controls that may underlie these working memory difficulties, but findings have been mixed. A quantitative synthesis of neuroimaging data through a meta-analytic approach offers a promising avenue to identify commonalities across studies. We conducted separate meta?analyses of structural and functional magnetic resonance imaging (MRI) data, with the latter focused …

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 …

Measurements Of Spinal Posture During Common Strawberry Picking Positions Using Inertial Measurement Units, Madeline E. Everson

Master's Theses

Physically demanding professions, such as agriculture, put people at an increased

risk for experiencing back pain. This is due to the awkward and harmful postures sustained

throughout their workday. While studies have been done demonstrating that back pain is

prevalent amongst this community, most do not collect motion capture (MoCap) data,

leaving the specifics of the kinematics, such as the amount of time spent in harmful

postures, unknown. Unfortunately, MoCap data is typically limited to that of a lab or

facility where the cameras are housed. Therefore, this study aimed to mitigate the

inaccessibility of traditional MoCap by validating 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.

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 …

Investigating The Influence Of Experimental Parameters On The Formation Of Gold Nanoparticles: A Green Synthesis And Design Of Experiments Approach, Isaac Opeyemi Subuloye

Master's Theses

This thesis examines the green synthesis of gold nanoparticles using catechin, a naturally occurring plant-derived compound, as both a reducing and capping agent. The synthesis process was guided by a structured Design of Experiments (DOE) methodology to ensure systematic investigation and optimization. A two-phase experimental approach was adopted. First, a full factorial screening design was used to evaluate the effects of catechin concentration, NaOH concentration, and pre-reaction time. This was followed by an optimization phase using a face-centered composite design to identify conditions that produce nanoparticles with ideal characteristics. The nanoparticles were analyzed using UV-visible spectroscopy and dynamic light scattering …

Changing The Channel: How Queer Representation In Mainstream Media Influences Social Perceptions In Young Adult Viewers, Lillian Joy Myers

Master's Theses

This thesis investigates the impact of queer representation in mainstream film and television on young adult viewers, with particular attention to how these media portrayals influence social perceptions and cultural understandings of queerness and LGBTQ+ identities. While queer visibility in mainstream media has increased over the past two decades, the quality and complexity of that representation remain generally inconsistent and infrequent. Drawing on sociological theories of representation and cultivation, along with GLAAD (Gay and Lesbian Alliance Against Defamation)’s Vito Russo Test as a guiding framework, this study explores both the quality and impacts of LGBTQ+ media visibility. The purpose of …

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 …

Negative Affect And Cannabis Use Outcomes In College Students: The Mediating Effect Of Protective Behavioral Strategies, Morgan Haga

Master's Theses

Particularly considering the ongoing changes in legalization, there has been a growing prevalence of cannabis use among college students. Similarly, students have endorsed increased mental health concerns following the COVID-19 pandemic. Resulting in a cycle of harmful use, research has supported a positive relationship between negative affect and cannabis-related negative outcomes. Protective behavioral strategies for marijuana (PBSM) have been successful in reducing cannabis-related negative outcomes; however, the frequency and utility of PBSM use for students experiencing increased negative affect is unknown. Participants included 330 college students (M_age = 19.17) from 12 U.S. universities who were predominately White non-Hispanic …

Connecting For Success: Evaluating The Frequency Of Check & Connect Meetings On Student Behavior, Kaylee S. Mckinney

Master's Theses

Dropout prevention efforts commonly address risk factors including chronic absenteeism, which continues to be a nationwide concern. Check & Connect is a student engagement intervention that aims to improve graduation rates and mitigate several risk factors of dropout. Previous research has failed to address if the frequency of Check & Connect meetings results in varied effectiveness of the intervention. The current study aims to evaluate the effects of modified frequency of Check & Connect meetings on academic engagement, term grade average, absences, and office discipline referrals through the use of a multiple baseline across participants design. Results revealed that students …

Forgotten Landscapes: Using Original Land Surveys To Understand The Historic Distribution Of Cane Brakes In Wayne County, Ms, Chad Mackness

Master's Theses

This study investigates the historical presence and ecological significance of Arundinaria gigantea (giant cane) in 1810, Wayne County, Mississippi, using original survey documents. These records provide rare quantitative insights into the distribution of cane brakes, revealing that A. gigantea possibly represented up to 44% of the surveyed landscape, likely second only to Pinus palustris (longleaf pine).

This research involved digitizing historical surveyors' notes, transcribing them into a structured format, and extracting spatial data for GIS analysis. The methodology developed for this research can be used to ensure the preservation and usability of these historical documents for future research. …

Do Finances Determine Our Fate?: Understanding The Relationships Between Socioeconomic Status, Inflammation, And Cancer Recurrence Risk, Faith Wilbourne

Master's Theses

Individuals of a low socioeconomic status (SES) are more likely to experience a cancer recurrence relative to individuals with a higher SES. This may be partially explained by the stressors of living with a low SES. These stressors can increase inflammatory markers known to elevate the risk of cancer development. Health-promoting behaviors such as exercise, adequate sleep, and a healthy diet can reduce systemic inflammation. Health behaviors may therefore moderate any potential relationship between SES and cancer recurrence risk. This study explored associations between SES (income, educational attainment) and inflammatory markers related to cancer recurrence while seeking to determine if …

Inside The Walls Of The Asylum: Exploring The Lives Of Individuals In The Mississippi State Asylum (1855-1935), Savannah V. Logan

Master's Theses

The Mississippi State Asylum (MSA), established in 1855, was the first such institution in but has been largely forgotten about since its closure in 1935. The cemetery associated with the facility, which is located on the University of Mississippi Medical Center campus, was recently rediscovered with new construction. As part of the Asylum Hill project, the remains of seven of the 7000 burials along with their mortuary artifacts were analyzed and allowed these forgotten individuals to once again regain their voice and tell a portion of their life story through osteobiographies.

The sample, dating to 1855-1899, included five males 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 …

Social Sprouts: A Play-Based Packaged Intervention - Improving Peer Interactions In Early Childhood Classrooms With A Novel Group Contingency, Brittany D. Garza

Master's Theses

Teaching prosocial skills such as positive peer interactions in early childhood settings not only promotes behavioral health but reliably predicts future learning outcomes. The literature suggests that decreasing levels of challenging behavior may improve peer interactions, and a feasible class-wide strategy that can address this combination of needs effectively is a group contingency. The current study investigated the effect of a novel group contingency, Social Sprouts, on both positive peer interactions and disruptive behavior. This study utilized a nonconcurrent multiple baseline design in three Head Start classrooms to evaluate the effect of this packaged intervention delivered just before and during …

Reflecting On Racial Microaggressions: The Impact On Food Consumption In Minority Women, Khadiza Akter

Master's Theses

U.S. laws, policies, and practices have been implemented to reduce forms of overt racism and discrimination. These structural barriers have been effective (e.g., Dovido & Gaertner, 2000; McConahay, 1986; Sue & Sue, 2007). Covert forms of racism, however, including racial microaggressions, are more difficult to address using structural changes and, therefore, continue to thrive (Omi & Winant 1994; Sue et al., 2007). Racist attitudes and discriminatory behaviors are sources of anxiety and stress (Kogan et al., 2014; Pascoe & Richman, 2009) with long-term anxiety and stress leading to elevated risks for mental and …

Female Preference And Prezygotic Isolation In The Fundulus Notatus Species Complex, Emilee K. Holderness

Master's Theses

Understanding how reproductive isolation arises between closely related species is central to evolutionary research. Hybridization is widespread across taxa and shaped by interactions among environmental factors, evolutionary history, genetic compatibility, and behavior. These forces often operate nonlinearly across space and time, yet mate choice is frequently assessed under artificial conditions that may not reflect natural behavior. To address this limitation, female mate preference was investigated within the Fundulus notatus species complex, where F. notatus and F. olivaceus hybridize at varying rates across replicate contact zones. Using a free-choice design, behavioral trials were conducted with individuals from populations characterized by high …

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 …

The Influence Of Rhodolith Algae On Life History Of The Painted Urchin, Lytechinus Pictus, Celine X. De Jong

Master's Theses

Rhodolith beds are globally distributed hotspots of diversity and productivity and serve as nursery habitats for some marine invertebrates. Poorly understood is whether rhodolith beds are nurseries because invertebrate larvae actively select them for settlement or migrate to them at later life stages. We studied the nursery role of rhodolith beds for the painted urchin, Lytechinus pictus at Santa Catalina Island, CA, USA. Subtidal surveys showed that in areas with greater live rhodolith cover, urchin density increased as well as mean urchin size. In caged substrate choice experiments, urchins selected rhodolith substrate relative to carbonate sand, supporting the notion that …