Digital Commons Network^™

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 …

Coloring Outside The Lines: Factors Facilitating Divergent Thinking, Michelle Baca Reinke

Master's Theses

Divergent thinking involves producing a multitude of unique and diverse ideas. The ability to “color outside the lines” is crucial to business, education, and social domains. The flexibility, originality, and fluency dimensions of divergent thinking are commonly assessed using the Alternative Uses Task, which involves generating uses for common objects. Prior research suggests that high identification (first-person perspective) with schema-inconsistent experiences increases flexibility, while semantic density (degree of conceptual associations) impacts originality and fluency inversely. However, their combined effects across multiple divergent thinking dimensions remain unexplored. The present research investigated the interactive effects of identification (high, low), schema consistency (consistent, …

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 …

Integration And Testing Of A Quadruped Robot With Ros2, Jeremy S. West

Master's Theses

The Cal Poly Legged Robotics Group has been developing research and teaching platforms for agile legged robotics since 2020. These platforms are expected to provide students with opportunities to develop complete legged-robot systems from low-level control to advanced robotics tasks such as motion planning and decision making. However, the current prototyped quadruped robot lacked the software and sensing capabilities for high-level quadrupedal gaits and advanced robotic research.

To address these challenges, this project developed Switch, a robotic platform that builds upon the previous BRUCE platform with significant hardware and software upgrades. Switch features a modular design that allows individual software …

Development Of A Control System For An 8-Dof Quadrupedal Robotic Research Platform, Jack Butler

Master's Theses

Quadrupedal robots offer a versatile locomotion option that can extend the operating space of a robot into uneven terrains. However, controlling these systems presents significant challenges due to nonlinearities introduced by various factors.

In this thesis, model-predictive control (MPC) is applied to an 8-DOF legged robot developed by Cal Poly’s Legged Robotics group. The MPC framework employs a lumped rigid-body model that treats the robot as a single rigid body with forces applied directly at the foot contact points. The controller is developed within the ROS2 environment, with integration of state estimation and gait-pattern generation, to provide maximum modularity and …

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 …

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 …

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 …

Predominant-Dominant Chains In Japanese Video Game Music, Evan R. Davis

Master's Theses

The short looping forms in Japanese video game music feature rapid modulations based on common chord progressions that necessitate contextual readings of harmonies in various keys to isolate how they manipulate tonal space. One such progression used by Japanese game music composers utilizes chains of predominant-dominant chords to move key centers by conflating function in minor-third related keys. These triumphant sounding transitional phrases are uniquely valuable in a medium dominated by stories of heroism and fighting authorities both earthly and divine. Building on the functional framework of 19^th century theorists and existing popular music research, two models are created …

High-Resolution Event Stratigraphy Of Ostracods In The Ozan Formation Of Texas And Arkansas, Denali L. John

Master's Theses

This study focuses on the high-resolution event stratigraphic framework of the lower Campanian Ozan Formation in Northeast (NE) Texas and Southwest AR which is richly fossiliferous in ostracods. Little research has been published on the Ozan Formation and even less dealing with Ozan ostracods. Additionally, correlation of Upper Cretaceous units between Texas and AR is controversial due to the general lack of good exposures in both regions and extensive faulting in Northeast Texas despite similar depositional environment across the region. This study calibrates the ranges of ostracods and creates an event stratigraphic composite that is orders of magnitude higher in …

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. …

Using Inquiry Classroom Experiences To Correct Student Misconceptions In Elementary Science: An Action Research Study, Hope A. Ellison

Master's Theses

Misconceptions in elementary science education can significantly hinder students' ability to construct accurate and lasting conceptual understandings. Grounded in the constructivist learning theory, this quasi-experimental study investigates how inquiry-based instruction influences the identification and correction of third-grade students’ misconceptions in science, specifically in the domains of energy, force, and matter. Using a pre- and post-test design, along with data derived from daily teacher field notes, the research was conducted with a sample of fifteen third-grade students at a public elementary school in Mississippi. The results, discussed in the methods section, revealed a statistically significant improvement in students’ conceptual understanding following …

Trust Across Difference In Radical Social Movement Organizations: The Case Of The Student Nonviolent Coordinating Committee, Kerstin Miller

Master's Theses

Social movement literature does not properly address trust between activists as a foundation of social movement organizations. This thesis aims to fill that gap by examining how trust within the Student Nonviolent Coordinating Committee, a radical civil rights organization in the sixties, was built and broken over the course of the decade. I drew on first-hand accounts written by SNCC activists to find patterns in how they thought about trust building and trust breaking in their own organization. I found that trust was built primarily through sustained interaction between activists, and that trust in the organization led to activists being …

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 …

Assessment Of Estuarine Respiration And Benthic Nutrient Fluxes In Mississippi Sound, Nur Pasha Sufian

Master's Theses

This study quantified seasonal and spatial variability of both water column and benthic respiration rates as well as benthic nutrient fluxes along the Mississippi Sound. Respiration was measured in recirculating incubation chambers using Firesting optical DO sensors (PyroScience GmbH), and changes in nutrient concentrations were assessed. Mean water column respiration rates ranged from 0.35 and 2.76 µM O₂ hr⁻¹, with the lowest rates in the winter and the highest in the summer while detectable nutrient concentrations (ammonium, (NH₄⁺), and soluble reactive phosphate (PO₄³⁻)) showed only slight decreases (< 1 µM) over all seasons. Sediment incubation chambers consistently had much greater oxygen declines than the water incubations and showed seasonal trends with the highest mean respiration rates measured in the summer and the lowest mean in the winter, with a range from 107.4 to 1514.9 µmol O₂ m⁻² hr⁻¹ (2.6 to 36.3 mmol O₂ m⁻² d⁻¹). Sediment incubations consistently showed increases in NH₄⁺ concentrations in the overlying water, resulting in calculated NH₄⁺ benthic flux rates of 0.73 to 379.01 µM N m⁻² hr⁻¹ with the lowest rates in the winter and highest rates in the summer. Although PO₄³⁻ concentrations were often below detection in cooler seasons, PO₄³⁻ flux also peaked during the summer (< 28.8 µmol P m⁻² hr⁻¹). In this study, temperature was a key regulator for estuarine respiration and benthic nutrient flux rates, and these rates were positively correlated with porewater nutrient concentrations and sedimentary organic matter. These findings illustrate that benthic respiration can contribute to water column hypoxia and that sediments serve as a source of nutrients to the water column. Overall, these findings provide us with valuable insight about the seasonal coupling of oxygen demand and nutrient flux in the Mississippi Sound and provide valuable baseline data for future biogeochemical modelling of hypoxia, eutrophication, and productivity.

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 …

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 …

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 …

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 …

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 …

Mechanoregulation Of Osteogenesis And Adipogenesis Of Human Mesenchymal Stem Cells, Justin Caron

Master's Theses

Bone-related diseases (e.g., osteoporosis) are primarily treated with pharmacologic therapies that often exhibit limited efficacy and substantial side effects. Currently, bone marrow derived mesenchymal stem cells (MSCs) have become one of most important cell options in bone regeneration due to readily available sources, strong proliferation abilities, weak immune rejection responses, and strong osteogenic differentiation potential. While identifying the most effective approach to enhance osteogenic differentiation of MSCs for bone regeneration is challenging, understanding the regulatory mechanisms is crucial for improving therapeutic efficacy. Recent research has focused on developing strategies to enhance osteogenesis, which involve biophysical and biochemical stimulation. Mechanical and …

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 …

Drug Delivery, Disulfide Crosslinked Hydrogel Coating For Polydimethylsiloxane (Pdms) Implant Materials, Paul A. Contos, Paul Anthony Contos

Master's Theses

Though polydimethylsiloxane (PDMS) is often used in medical devices due to its desirable mechanical properties and biocompatibility, its surface is often prone to bacterial adhesion. This is especially a problem for catheters, where bacteria can adhere and form biofilms that can in turn result in Urinary Tract Infections (UTI). In order to deter the presence of UTI causing bacteria on PDMS catheters, methods were developed to formulate a disulfide crosslinked hydrogel coating and create a methodology to allow adhesion to a PDMS substrate. The hydrogel coating discussed in this paper will be synthesized by chemically crosslinking stimuli-responsive vesicles, that carry …

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 …