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Bacterial Chondronecrosis With Osteomyelitis In Broilers: Etiology And Selected Mitigation Measures, Khawla Saud Alharbi

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis (BCO) is the predominant cause of lameness in broiler chickens. It mainly impacts broiler production and animal welfare, causing substantial financial losses accounting for 1- 2% due to bird condemnations at the marketing age. Remediating BCO lameness disease demands investigating its causes using appropriate models and evaluating preventive measures, such as enhancing epithelial tissue health and tight junction integrity in the digestive and respiratory tract, strengthening immune functions, and improving bone strength. Therefore, the objectives of this dissertation were to 1) study predisposing factors for BCO lameness by investigating the effects of deoxynivalenol (DON) and fumonisin …

Examining The Combination Of Race-By-Age Segregation On Violence In Little Rock, Arkansas, Karissa Kruse

Graduate Theses and Dissertations

The Present study addresses the issue of residential segregation. Specifically, how the physical isolation of populations segregated based on both age and race affects violent crime. The sample includes all 155 Census block groups, which represent neighborhoods, in the city of Little Rock Arkansas. Data is accessed from the U.S. Census and the Little Rock Police Department. The current study asks: does the segregation of juveniles by age and race affect the distribution of crime? The theoretical frameworks guiding this research are social disorganization theory, structural-cultural theories of crime, the racialization of space perspective, and routine activities theory. The key …

Polyphenol-Protein Interactions In Pigmented Cereals – A Clean-Label Approach To Tailor Starch Viscosity, Annegret Jannasch

Graduate Theses and Dissertations

Viscosity plays an important role in the food industry as it affects the quality, processing stability, and shelf-life of food and impacts physiological responses such as satiation and satiety. Greater viscosity reduces food intake by increasing the perception of satiety, primarily by delaying gastric emptying and increasing tactile stimulation. Starch is commonly added to food products as a viscosifying ingredient, which often involves chemically modifying the starch via cross-linking, to enhance its resistance to high shear, temperature and acidity. However, chemically modified starches are not “clean-label” ingredients due to the use of toxic chemicals. Therefore, further exploration is needed to …

Towards Multimodal Scene Graph Generation Approaches To Video Understanding, Trong-Thuan Nguyen

Graduate Theses and Dissertations

This thesis advances video understanding by enhancing Video Scene Graph Generation (VidSGG) through improved temporal modeling, the integration of long-range temporal dependencies via continuous updates to interaction histories, and the utilization of Large Language Models (LLMs) for scene graph reasoning. To this end, three novel datasets and corresponding approaches are introduced. First, the ASPIRe dataset incorporates interactivity annotations and leverages the Hierarchical Interlacement Graph (HIG) for hierarchical temporal modeling, providing deep insights into scene changes and effectively capturing intricate interactions. Next, the AeroEye dataset, focusing on drone videos, is paired with the Cyclic Graph Transformer (CYCLO), which establishes circular connectivity …

The Uneven Disruptions Covid-19 Caused To Scholars’ Publication: A Preregistered Study, Marco De Prosperis

Graduate Theses and Dissertations

This proposed, preregistered study investigates the uneven impacts of COVID-19 on scholarly productivity among University of Arkansas faculty, focusing on how demographic and professional factors—such as gender, ethnicity, academic rank, tenure status, field of study, and the presence of children—may have moderated productivity during the pandemic. Utilizing a non-experimental, cross-sectional design, this research will collect data from 160 full-time faculty members through an online survey. Grounded in Role Theory, the study will examine role conflict and enrichment as faculty navigated shifting responsibilities in research, teaching, and caregiving during remote work. This study is particularly relevant as many assistant professors who …

Administering Grant-Subsidized Workforce Training: A Critical Case Study, Kaleb Preston Futch

Graduate Theses and Dissertations

Grant monies are distributed for the purpose of funding workforce training programs aimed at affecting the skills gap in the United States. While research has shown that these grants are being awarded, there is not a well-established standard for designing and implementing the programs they fund. This study focuses on recording and classifying the lived experiences of grant staff working on a state funded workforce training program in the United States. This study will employ a qualitative case study approach designed to capture and codify, in the words of those most familiar with it, the aspects of the grant program …

In Vitro Investigation Of Macrophage Functional And Metabolic Modulation, Shelby Nicole Bess

Graduate Theses and Dissertations

Macrophages are a subset of immune cells with a variety of functions that are abundant in numerous tumor types such as colorectal and breast cancer. It has been suggested that macrophages may serve an important function as immune mediators in tumor behavior; however, macrophage activity is complex and remains not completely understood. The overall goal of this dissertation was to explore and exploit tumor-associated macrophage phagocytic function and the changes in their interactions with cancer cells in an in vitro mouse model and in 2D and 3D in vitro culture models. First, we wanted to better understand macrophage behavior under …

Applying A Strained Masculinity Framework To Honor Killings And Incel Murders, Shreeya Gandhi

Graduate Theses and Dissertations

The current study explores how pursuits of hegemonic masculinity can shape the comparative nature of Gender Based Violence (GBV), specifically incel killings and honor killings, in the United States over the past 30 years. Drawing from Allison and Klein's (2021) strained masculinity framework and employing a homicide narrative approach, a qualitative theme analysis is conducted to determine whether existing thematic categories of strained masculinity determined relevant in prior research also apply to these relatively are forms of deadly GBV. Honor killing data come from Hayes, Freilich & Chermak (2016) and incel killing data come from the Extremist Crime Database (ECDB). …

Quantifying The Effects Of Urbanization On Stream Nutrient Loads And Decomposition, Caroline Anscombe

Graduate Theses and Dissertations

Urban stream syndrome (USS) refers to the common symptoms of degradation in urban streams globally. Two symptoms of USS are increased nutrient and salt concentrations in streams, affecting ecosystem structure and function. Excess nutrients negatively impact freshwater ecosystems, placing downstream habitats at risk of eutrophication and harmful algal blooms. Excess salt runoff, derived from road salt application, is toxic to freshwater organisms and affects leaf litter decomposition, the base of aquatic food webs. Here, I aimed to quantify the effects of nutrient pollution and salinization on urban water quality and ecosystem function. Despite the widespread consequences of nutrient pollution, most …

Creating A Sense Of Home: Hispanic Students At Hispanic-Serving Institutions, Eva Cordero

Graduate Theses and Dissertations

Hispanic-Serving Institutions (HSIs) provide critical access to higher education for Hispanic students, yet their designation is based on enrollment rather than active support for student success. The purpose of the study was to describe and explore the sense of belonging for Hispanic students at a select Hispanic Serving Institution (HSI) with a high percentage of Hispanic students. Using photo voice, document analysis, and semi-structured interviews, the study identifies five key themes: (1) agency in belonging, (2) club participation, (3) fostering a sense of value, (4) institution and institutional agents, and (5) scholarship and funding. Findings underscore the need for HSIs …

Elucidating The Mechanisms Of Collagenase H From Hathewaya (Clostridium) Histolytica In Collagen Degradation And Developing A Cross-Linked Platform For Efficient Capture And Release Of Adeno-Associated Virus Serotype 2 (Aav2), Adjoa Otubea Bonsu

Graduate Theses and Dissertations

In biological systems, Hathewaya (Clostridium) histolytica secretes collagenases that degrade structural collagen in host tissues and cause tissue necrosis. Despite their detrimental effects, these enzymes have significant therapeutic potential by effectively digesting various collagen subtypes to treat connective tissue disorders. The bacterium produces two homologous collagenases, ColG and ColH, with a catalytic module crucial for hydrolyzing collagen and binding domains, including collagen-binding domains (CBDs) and polycystic kidney disease-like domains (PKDs), for substrate interaction.

Although the crystal structure of the catalytic module of collagenase G (ColG) has been determined, shedding light on its chew-and-digest mechanism, the structure of collagenase H (ColH) …

From Adolescence Into Adulthood: How Exclusionary Discipline And Sex Impact Early Adulthood Social And Economic Opportunities, Madeline Shanahan

Graduate Theses and Dissertations

The school-to-prison pipeline has established the relationship between school exclusionary discipline and an increased likelihood of experiencing criminal justice contact. Furthermore, exclusionary discipline serves as a precursor to several negative life outcomes, including educational and economic disadvantages. Using a life course perspective and longitudinal data from the Future of Families and Child Wellbeing Study (FFCWS) collected from 1998 to 2024, this study aims to understand the role that sex plays in exclusionary discipline and explores sex differences in early adulthood life opportunities post-exclusionary discipline. This study utilizes logistic regression analyses to answer the following questions: (1) Are there different early …

Exploring Latent Mediation Through Bayesian Regularization Methods Of Lasso, Ridge, Horseshoe, Spike-And-Slab, Ethan Harris

Graduate Theses and Dissertations

Regularization is a powerful tool to combat overfitting and drive sparsity in complex models. Regularization was initially applied in regression modeling but has been increasingly utilized in structural equation modeling where its utility in identifying the essential components has helped improve modeling. As structural equation models have increased in complexity both in the number of indicators but also the number of latent factors, researchers have begun to investigate how applying Bayesian regularization to these systems can further push the limits on modeling complex models with limited sample sizes. One area where research is limited is the application of Bayesian regularizations …

Comparison Of Airborne Lidar-Derived Elevation Data In Fayetteville, Arkansas, Usa, Angelica M. Otting

Graduate Theses and Dissertations

Light detection and ranging (lidar) laser scanners are prominent remote sensing tools to produce high resolution three-dimensional (3D) imagery of the Earth’s surface. These laser scanners combined with global navigation satellite systems (GNSS) and real-time kinematic (RTK) reference stations can generate some of the most accurate ground surface imagery and elevation data for terrain mapping and related applications. Lidar aerial survey is an important tool in industries such as architecture, civil engineering, forestry, geology, geography, and agriculture where digital terrain models (DTMs) can be used to examine the geographical landscape and urban industry. Currently, there are three different common laser …

Contrastive Learning Techniques For Fraud Detection, Vinay Madanbhavi Shashidhar

Graduate Theses and Dissertations

Detecting fraud in computing platforms involves identifying malicious user sessions, often using deep learning models, but several challenges hinder effective deployment. Attackers can craft diverse malicious sessions that closely resemble normal ones, complicating the learning of robust decision boundaries. While supervised contrastive learning offers a promising solution through class-specific clustering, its potential remains underexplored. Real-world datasets typically contain few labeled malicious sessions and many normal ones, creating an open-set anomaly detection challenge. Costly expert annotation further limits labeled data, especially for smaller organizations, leading to Positive Unlabeled (PU) learning and noisy label learning issues. Organizations are increasingly turning to LLMs …

An Instructional Remodel: How Adopting A Unifying Model-Of-Instruction Impacted Teacher Self-Efficacy And Teacher Development And Evaluation Efforts In A Midwestern High School, Charles D. Patterson Carpenter

Graduate Theses and Dissertations

This mixed methods study sought to determine the effect of adopting a unifying model-of-instruction on teacher self-efficacy and the development and evaluation processes of administrators. By assessing the level of teacher self-efficacy (Tschannen-Moran & Hoy, 2001) in the nascent stages of the instructional model’s implementation, then reassessing it after a multiple-month sequence of professional learning, the researcher provides a judgment on statistical significance concerning the two measurements and conjectures the extent to which the instructional model impacted any differences in self-efficacy levels. Using two separate “before and after” interviews with purposefully selected administrators, the researcher explored how the unification of …

Conservation Agriculture Practice Effects On Greenhouse Gas Emissions From Fine-Textured Soils In Arkansas, Lauren Gwaltney

Graduate Theses and Dissertations

Biochar application and reduced tillage (RT) are both practices within the conservation agriculture framework, but specific impacts of these practices on direct greenhouse gas (GHG) emissions still require investigation in varied agricultural systems. This research aimed to evaluate the effects of biochar source (i.e., powder- and pellet-sized) and application rate (i.e., 0, 2.5, and 5 Mg ha^-1) on GHG production in simulated furrow-irrigated rice (Oryza sativa) in a greenhouse experiment, and to evaluate the effects of RT relative to conventional tillage (CT) on GHG production in soybean (Glycine max) in southeast Arkansas. Both studies …

Space And Subjectivity In The Emerging American West, Scott Hendry

Graduate Theses and Dissertations

The American West resists theoretical definition. As myth, ideal, region, contact zone, place, space, symbol, territory, home, assemblage, dream, and home, the West is continually changing. As a region, the West is not a closed space; it is an open, ongoing constellation of processes, an unfolding simultaneity of storied events or happenings. This dissertation, “Space and Subjectivity in the Emerging American West,” explores literature and cinema of the modern West. My project seeks to answer the question “What is the American West?” by examining the work of novelists, poets, filmmakers, cultural geographers, philosophers, and photographers who reimagine identity, locality, and …

Shaping Minds, Shaping Future: Analyzing K-12 Climate Change Education Policy Preferences In Arkansas, Nataliia Borozdina

Graduate Theses and Dissertations

Climate change education in K-12 public schools is a highly debated and divisive policy issue, particularly in politically conservative states such as Arkansas, where ideological divisions often dominate and shape public attitudes and policy preferences. This dissertation examines the attitudes, preferences, and behavioral intentions of three key stakeholder groups, namely the policy elites, general public, and educators toward climate change education policies in K-12 public schools in the state of Arkansas. While political party affiliation is an important factor, this study explores a more nuanced relationship by considering the interplay of Cultural Theory, risk perception, trust in government, climate change …

Adversarial Machine Learning: Methods For Attacks And Defenses, Minh Hao Van

Graduate Theses and Dissertations

With the rapid development of machine learning in real-world applications, enhancing security plays an important role. Adversarial machine learning focuses on understanding malicious actions from attackers and developing defensive techniques against such threats when deploying machine learning systems. An attack can occur in different scenarios, such as poisoning attacks during the training stage and evasion attacks during the testing stage. Although extensive research has explored defense strategies to deal with these harmful attacks, there is a need for further research into areas such as how to counteract malicious attacks with healthy noise or how to train an adaptive defense against …

Real Time Adaptive Control Of A Pid Via Genetic Algorithm Machine Learning Systems, Cemre Tas

Graduate Theses and Dissertations

The most common control method that is utilized by all industries across the world is the proportional-integrative-derivative controller (PID) due the relatively low cost and complexity of the system. However, there are draw-backs with PIDs, it is not adaptative to a changing system, so it works on nominal systems, and it starts breaking down when a system begins to have a non-linear response. The method chosen to overcome both is the utilization of machine learning with the use of genetic algorithms.

This method allows any PID system to be capable of adapting in real-time, while not adding significant additional cost …

Gene Expression And Transfection Of C15orf57 In Chicken Show Clear Correlation To The Function Of The Ap2 Complex, E. Ashton Magdich

Graduate Theses and Dissertations

Discovering the functions of functionally unknown genes has made a huge impact on biological understanding including poultry species. In this thesis, C15orf57 (or C5H15orf57, chicken chromosome 5 human ortholog H15 open reading frame 57), was studied to understand its genetic characteristics and function. Chapter one is literature reviews on annotation of genes, the gene information on C15orf57, the importance of characterizing unknown genes in the genome, and what is known now about C15orf57. The Chapter 2 is for the structural characterization of C15orf57, gene expression of C15orf57 in various organ tissues using the qPCR method and effect of overexpression of …

Controls On Nutrient And Sediment Export In A Non-Perennial Agricultural Stream, Kathleen Cutting

Graduate Theses and Dissertations

Climate change is expected to increase flow variability and intermittency in streams, changing the magnitude and timing nutrient and sediment delivery. This may exacerbate water quality issues in agricultural landscapes, where nutrient and sediment inputs are often elevated. Elevated nutrients can drive eutrophication in downstream waterways, and excess sediment loss can decrease primary productivity. Non-perennial headwater streams are particularly vulnerable to the impacts of climate change and agriculture as they serve as key sites for nutrient cycling at the terrestrial-aquatic interface. Despite their importance, the interactive effects of agriculture and stream intermittency, as well as unpaved roads in rural watersheds …

Penny For Your Thoughts: Exploring Mechanisms Linking Socioeconomic Status And Cognition, Colton Hunter

Graduate Theses and Dissertations

Socioeconomic status is a complex psychological construct linked to a number of professional and personal barriers, including cognitive deficits. Throughout this dissertation, I seek to examine the mechanisms that link socioeconomic status and cognition. First, I explore potential mediators in the link between adolescent family income and cognition in adulthood, identifying education, stressful life events, inflammation, and family education expectations as significant mediators. Next, I examine the effects of writing-based stress manipulations on long-term memory and working memory, as these effects may mimic stress from financial worry. In doing so, I identify potential effects on working memory parameters. Finally, in …

The Future Of Fashion: A Systematic Literature Review On Consumer Willingness To Pay For Green Apparel, Emma Clark

Graduate Theses and Dissertations

In recent years, consumers have become highly aware of the environmental impact of their purchases, specifically of apparel products. Accordingly, apparel brands have increasingly focused on enhancing the sustainability of their product offerings to attract environmentally conscious consumers and elevate their brand image (Dangelico et al., 2022). Furthermore, most sustainably produced products are priced higher for consumers compared to standard alternatives (Elmanadily & El-Deeb, 2022). Research has shown that consumers can accept higher prices for products that do less harm to the environment (Gomes et al., 2023), but it has yet to be determined in which cases this is consistently …

Effects Of Cholesterol Concentration On Liposome And Proteoliposome Behavior, Ehsaneh Khodadadi

Graduate Theses and Dissertations

Cholesterol is crucial in modulating the behavior and characteristics of biological membranes, liposomes, and proteoliposomes, for instance in drug delivery applications. Cholesterol regulates membrane stability by influencing lipid density, phase separation, and protein-membrane interactions. In planar bilayers, cholesterol enhances membrane thickness, reduces permeability, and promotes lipid ordering, adding rigidity and fluidity. Cholesterol also modulates membrane curvature in curved bilayers and vesicles, stabilizing low-curvature regions. In this work, all-atom molecular dynamics (MD) simulations were employed to examine how varying cholesterol concentrations influence the structure and dynamics of membranes, focusing on planar and curved geometries. Bilayers with cholesterol molar ratios of 0%, …

Koszul Cohomology Of Canonical Products, Alexander Scott Duncan

Graduate Theses and Dissertations

In this thesis, we give a complete classification of the Koszul cohomology groups K_p,₁(C, B, ω_C ⊗ B) on a smooth curve C of genus g ≥ 2 with B p-very ample. Such a classification in the case B = ω_C has been incomplete until [5]. The classification follows easily from our main result which precisely calculates K_p,1(C, B, B ω_C ⊗ B) in terms of h⁰(C, B). This result also handles the case B = ω_C. A straightforward …

Regulatory Compliance Standards And Power System Reliability: A Study On Inverter-Based Resources, Pirouz Honarmand

Graduate Theses and Dissertations

The increasing penetration of renewable energy, particularly inverter-based resources (IBRs), has reshaped the dynamics of modern power systems. This thesis investigates the impact of regulatory compliance, especially frequency ride-through requirements under NERC PRC-029-1, on the performance and reliability of interconnected multi-area systems. Using a MATLAB/Simulink-based state-space model built on the foundational structure proposed by Murty [31] and augmented with advanced control methods such as Linear Quadratic Regulator (LQR) control from Mackey and McCann [32] and further refined in the context of IBR damping by Alsarray and McCann [33], we explore three configurations of a three-area load frequency control (LFC) system. …

Atomic Level Characterization For The Transport Cycle Conformational Pathways Of Multidrug Resistance Protein 1 (Mrp1), Samuel Wamwere Mwatha

Graduate Theses and Dissertations

The multidrug resistance-associated protein 1 (MRP1/ABCC1) is an ATP-binding cassette (ABC) transporter that mediates the cellular efflux of endogenous and xenobiotic substrates, including therapeutic drugs. Its overexpression is a major contributor to multidrug resistance in cancer, which tends to result in negative clinical results. Even with considerable progress made in structural biology, the intricate details of how membrane lipid composition affects the conformational changes and functional switches of MRP1 still lack explanation.

This thesis employs long-timescale, all-atom molecular dynamics (MD) simulations to study the influence of various lipids on MRP1 lipid bilayer environments. Both inward-facing and outward-facing conformations of MRP1 …

Impact Of Smartphone Usage On The Performance And Satisfaction Of Hospitality Employees, Karalee Anne Taves

Graduate Theses and Dissertations

This study examined the impact of smartphone usage on the job outcomes (job satisfaction and performance) of employees, specifically focused on the hospitality industry, where employees’ income and performance heavily rely on emotional labor. The research was aimed to distinguish between negative smartphone activities (e.g., doomscrolling, social comparison) and positive activities (e.g., listening to calming music, engaging in stimulating games) to determine how these behaviors affect employees. Using the Stimulus, Organism, Response Cognitive Theory (SOR), the study examined if positive smartphone usage enhances well-being and job outcomes, while negative usage diminishes them. The results revealed that smartphone usage does not …