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Impacts Of Toxic Fescue Seed Consumed By Pregnant Heifers On Maternal Blood Flow And Offspring Growth Parameters: Potential For Melatonin As A Therapeutic To Improve Offspring Growth, Rachel Scott

Graduate Theses and Dissertations

The southeastern United States is home to endophyte-infected (E+), toxic, tall fescue grass. Consumption of E+ fescue by livestock has been linked to fescue toxicosis, a disease reported to cost the United States beef industry around $1 billion in annual losses. The primary objective of this dissertation was to evaluate the influence of pregnant cattle consuming E+ seed during gestation on uterine artery blood flow and growth performance of female offspring. The secondary objective was to investigate melatonin supplementation as a mitigation strategy for expected fescue-associated decreases in uterine artery blood flow and offspring growth performance. The study reported in …

Identifying Predictors Of Student Success During Occupational Therapy Level Ii Fieldwork, Melissa R. Foster

Graduate Theses and Dissertations

The training paradigm for new occupational therapy (OT) practitioners includes both didactic classroom learning and clinical fieldwork experiences in order for them to establish clinical competency. However, many students struggle with the theory-to-practice gap of translating classroom knowledge to clinical experiences. When students struggle in this manner, it causes stress for all stakeholders involved, including the fieldwork educator, clinic managers, OT program faculty, as well as the student.

This study aims to avoid this stress by identifying predictors of student success by analyzing data from recent graduates of the University of Arkansas/University of Arkansas for Medical Sciences OT program through …

Evaluation Of Fluridone In Rice, Maria Carolina De Carvalho Rocha Souza

Graduate Theses and Dissertations

The increasing pressure of Palmer amaranth [Amaranthus palmeri (S.) Watson] in rice (Oryza sativa L.) fields demands new chemical control options to manage this weed. The recent labeling of fluridone on this crop from the three-leaf rice stage offers an additional residual herbicide for battling Palmer amaranth; however, research is needed to evaluate its effectiveness and rice tolerance. Field experiments were conducted to evaluate Palmer amaranth control and rice tolerance to fluridone across different locations in Arkansas in 2022, 2023, and 2024. Preemergence (PRE) applications of fluridone at 168 g ai ha^⁻1; (1× label rate) and 336 …

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 …

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 …

Exploring The Relationship Between Technical College Faculty Members’ Length Of Teaching Experience And Their Moral Identity, William Abney

Graduate Theses and Dissertations

This study investigates the relationship between faculty members’ length of teaching experience and their moral identity at a technical college in the Southeastern United States. Utilizing a quantitative approach, the research aims to determine whether a significant correlation exists between an instructor’s tenure in postsecondary education and their moral identity, as measured by the Moral Identity Questionnaire (MIQ). Additionally, the study examines the potential moderating effect of gender on this relationship. Data will be collected through a Qualtrics electronic survey distributed to all faculty members at the college, ensuring anonymity and minimizing survey errors. The survey includes demographic questions and …

Comparison Of Rt-Qpcr And Rt-Ddpcr On Assessing Model Virus In Wastewater, Wafa Youssfi

Graduate Theses and Dissertations

There is an increasing demand for quantifying viral loads in diverse wastewater systems using polymerase chain reaction (PCR). This study evaluates the performance of two commonly used workflows: reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR) in wastewater. We compared the two methods by measuring the viral ribonucleic acid (RNA) of a model virus Phi6 in samples collected from various treatment stages at the Westside Wastewater Treatment Facility in Fayetteville, AR. RNA was extracted from real and synthetic wastewater samples and analyzed in parallel using both RT-qPCR and RT-ddPCR. Findings reveal that both methods demonstrated similar …

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 …

Implications Of Acetylation And Phosphorylation On Metabolic Enzymes, Nour Fatema

Graduate Theses and Dissertations

All living things depend on glycolysis and the TCA cycle for energy production and metabolic control. Post-translational modifications (PTMs) such as acetylation and phosphorylation, which can change enzyme activity, substrate binding, and overall metabolic balance, tightly regulate these pathways. Diseases like cancer and metabolic problems are associated with disruptions in these alterations.

Serine phosphorylation and lysine acetylation are two of the many PTMs that are evolutionarily conserved processes that alter protein function. Previously thought to be a static histone alteration, acetylation is now understood to be a dynamic regulator of metabolic enzymes that modifies contacts, charge, and conformation. In response …

Exploring Hybrid Cohort-Based Doctoral Program Features That Support Nontraditional Doctoral Students’ Persistence: A Preregistered Case Study., Glenda Winborn

Graduate Theses and Dissertations

With the rise of hybrid learning models, non-traditional learners have greater access to doctoral education. However, attrition rates from doctoral programs remain high, ranging from 40% to 50% across all doctoral programs and exceeding these levels in online non-traditional programs. Numerous causes of attrition or persistence in doctoral studies have been researched and can affect the student, the academic institution, and the broader academic society. This qualitative case study will explore adult and lifelong learning doctoral students' perceptions of the programmatic and instructional support resources that have helped improve persistence in their program. Two of the important programmatic features of …

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%, …

Bang!: Real-Time Measurements And Transcriptomics Of Metabolic Reprogramming In Activated Macrophages At Fever Temperature, Kenneth Howard Taylor

Graduate Theses and Dissertations

We investigated the real-time metabolic rates of activated macrophage cell lines derived from mouse, chicken and rainbow trout. Each species showed a different kinetic signature with metabolic rates accelerating under fever conditions specific to each organism. Upon activation mouse macrophages increased their rate of glycolysis early and then a later reprogramming phase occurred with a dramatic decrease in oxidative phosphorylation (OXPHOS) accompanied by a reciprocal second increase in glycolytic rates. Chicken macrophages showed an initial increase in both glycolytic and OXPHOS rates. The late drop OXPHOS rates also occurred in chicken however there was no reprogramming that occurred as glycolytic …

Male And Female Contributions To Sexual Dimorphism, Catherine L.W. Clayton

Graduate Theses and Dissertations

Since Darwin, the evolution of sexual dimorphism connects to different evolutionary mechanisms reflecting both natural selection and sexual selection. In primates, body size dimorphism has been attributed to multiple factors, including sexual selection, fecundity selection, ecological selection, and other factors. In contrast, canine tooth size dimorphism has been primarily associated with sexual selection in males with minor change in females, with other factors playing only a secondary role. This suggests that the degree to which body size dimorphism and canine size dimorphism covary, controlling for phylogeny, should reflect the strength of sexual selection. Conversely, the magnitude of divergence between the …

Fixed-Time Artificial Insemination Protocols Using Pre-Synchronization In Suckled Beef Cows, Wyatt Eugene Weber

Graduate Theses and Dissertations

Adoption of artificial insemination by beef producers has been limited within the United States. Estrous synchronization (ES) for fixed-time artificial insemination (FTAI) has been one of the most effective ways to implement artificial insemination into beef production systems, but its efficiency has primarily been restrained by the dependency on the effectiveness of the initial gonadotropin releasing hormone (GnRH) injection in many FTAI protocols. The hypotheses of these studies were to determine practical methods of pre-synchronization to improve current FTAI protocols, ultimately increasing beef herd reproductive performance. The objective was to evaluate the use of prostaglandin F2α (PGF) and progesterone (P4) …

An Analysis Of Cellular And Tissue Function Of Lipin In Drosophila Melanogaster, Judah Christian Scott

Graduate Theses and Dissertations

Regulation of energy expenditure and energy storage is a key characteristic of life. Numerous enzymes play a crucial role in regulating energy metabolism. Lipins are a highly conserved family of proteins that function in both lipid synthesis and gene regulation. In the glycerol-3 phosphate pathway, lipins act as a phosphatidate phosphatase (PAP) producing diacylglycerol. In gene regulation, lipins act as transcriptional co-regulators of metabolic genes. The enzymatic PAP activity occurs in the cytoplasm; however, for lipins to function as gene regulators, they must translocate into the nucleus. Nuclear translocation is facilitated by the nuclear localization signal (NLS) within the protein. …

Geospatial Modeling Of Winter-Related Property Damage In Arkansas, Braedyn Mcbroom

Graduate Theses and Dissertations

Storm Data, a monthly publication by the National Weather Service with records of weather events, reports on property damage caused by natural hazards. Since 1996, the database has included winter-related events. While the property damage data is considered incomplete, no other unique, public datasets report winter-related property damage at the county level. From 1996 to 2024, Arkansas ranked #1 in winter-related property damage. To understand the factors that are driving property damage and potentially reduce Arkansas’ vulnerability to it, three groups separated by temporal periods, i.e., “2000” (01/1996 - 06/2005), “2010” (07/2005 - 06/2015), and “2020” (07/2015 - 06/2024) …

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 …

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 …

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 …

Exploring The Relationship Between Novice Teacher Autonomy And Workplace Engagement, Burnout, And Intentions To Remain In The Teaching Profession, Bryce Bennett

Graduate Theses and Dissertations

Administrators and experienced faculty frequently disagree on the degree of autonomy that should exist for classroom teachers. Administrators seeking to make adjustments to the levels of autonomy experienced by their teachers may struggle to account for differences between novice teachers and their more seasoned counterparts. This study applies researched-based models for exploring the relationship between various job resources and demands and their ultimate impact on workers. A mixed method designed employing a survey across three large school districts in Arkansas asked participants questions intended to uncover the degree of autonomy novice teachers typically experience, levels of burnout & workplace engagement, …

Evaluating The Impact Of Work-Based Learning On Postsecondary Completion And Job Placement Of Electronics Technology Students, Amanda J. Seidenzahl

Graduate Theses and Dissertations

The manufacturing industry today is facing a critical shortage in the availability of talent and skills needed in an ever-changing technological workforce. With an estimated 2.1 million jobs in the manufacturing industry predicted to be unfilled by 2030, organizations are struggling to find a workforce with the skills needed for this evolving industry (NAM, 2020; Ahmad, 2019). Employers have often suggested there is a lack of alignment between classroom experience in higher education, and work-based learning (WBL) is one option to bridge this gap (Krishnamoorthy & Keating, 2021). WBL provides real world experiences that connect learning in the classroom (Krishnamoorthy …

Leveraging Natural Variation In Yeast To Understand Susceptibility Differences In Parkinson’S Disease, Julio Andres Molina Pineda

Graduate Theses and Dissertations

Parkinson’s Disease (PD) is a neurodegenerative disorder that causes countless suffering around the world. Both forms, familial and sporadic, have been associated with the misfolding and cytotoxicity of α-synuclein, an otherwise non-pathogenic protein suspected to have various roles in the normal maintenance of the central nervous system. Model organisms have emerged as great vessels to uncover the cellular and molecular mechanisms that shape α-syn biology, and great strides have been made to understand it. Yet, it is still unclear why some individuals are affected by α-syn toxicity, while others not so much. Since it’s extremely complicated to study and probe …

The Evolving Changes In The Regionalization Of Export Bans On U.S. Poultry Trade From The 2015 And 2022 Highly Pathogenic Avian Influenza Events, Kylie A. Roesler

Graduate Theses and Dissertations

As food security becomes a growing concern worldwide in a trading system dominated by globalization, the safeguarding of a bio-secure food system is at risk. One of the greatest risks to this stability of the system is, highly pathogenic avian influenza or HPAI which is growing in frequency and impact. Therefore, the global response to disease events is evolving into a newfound understanding of disease prevalence across the animal protein industries. This study will analyze the 2022 HPAI event in the United States regarding the regionalization of restrictions imposed by trading partners accounting for trade agreements executed. The examination of …

Evolutionarily Conserved Functions Of The Gene Frazzled In Midline Axon Guidance In Drosophila Melanogaster And Tribolium Castaneum., Piyasi Ghosh

Graduate Theses and Dissertations

Axon guidance in bilaterians is often controlled by various signaling pathways in the nervous system, which determine the fate of the axons if they cross the midline or not. One such pathway involved is the ligand-receptor pair Netrin (Net) and Frazzled (Fra), which is also known as the attractive pathway that promotes midline crossing axons in insects and other bilaterians. Orthologs of the pathway ligand Netrins and their receptors Frazzled [Fra] in insects and Deleted in Colorectal cancer [DCC] in vertebrates are widely conserved in bilaterians. How well these regulatory roles of the protein are conserved is poorly understood. In …

Sibling Groups And Family Adaptability And Cohesion Among Emerging Adult Women, Julianne M. Post

Graduate Theses and Dissertations

This study examined how sibling group size is related to family adaptability, cohesion, and individual resiliency outcomes during emerging adulthood. Using Bowen's Family Systems Theory and Olson's Circumplex Model, the research investigates sibling subsystems as sites where systemic imbalances are first experienced within families. Data from 124 college students revealed that larger sibling groups were associated with marginally higher disengagement and chaos resulting in decreased perceived social support, suggesting resiliency implications for youth growing up within larger families. While sibling size didn't directly predict mental health, family dynamics significantly mediated the relationship between sibling composition and resiliency outcomes. Demographic factors …

Bacterial Chondronecrosis With Osteomyelitis In Broiler Chickens: Experimental Lameness And Additive Probiotic Treatments, Amanda Anthney

Graduate Theses and Dissertations

With the global population already surpassing 8.2 billion and expected to reach 9.7 billion by 2050, the poultry industry has seen a surge in demand due to its unmatched efficiency and affordability for consumers across the globe. Selective breeding and quality nutrition developments since the industry's commercialization have allowed producers to grow broilers up to 7 pounds by market age. While this extraordinarily efficient process has allowed quality poultry products to be available worldwide, the modern-day broiler has developed a multitude of musculoskeletal issues. Due to the lack of integral skeletal development to match the rapid production of muscle tissue, …

Characterization Of Streptococcus Gallolyticus: An Emerging Pathogen Causing Turkey Streptococcosis, Latasha S. Gray

Graduate Theses and Dissertations

During the past five years, there has been an increased occurrence of Streptococcus gallolyticus in young turkey poults. This emerging pathogen previously affected turkey flocks without any indication of disease prior to acute mortality. However, recently there has been two cases of neurological presentation associated with S. gallolyticus subsp. pasteurianus that are unique to traditional disease presentation in turkey poults. The objectives of the present dissertation were to compile data associated with the two neurological cases and compare different S. gallolyticus strains as well as pathogenic Enterococcus cecorum to the neurological strains. The two neurological cases occurred between July and …

Application Of Ordinal Regression Models To Acquired Stress Resistance In Wild Strains Of Saccharomyces Cerevisiae, Carson Stacy

Graduate Theses and Dissertations

This thesis explores the application of ordinal regression to the analysis of semi-quantitative growth assays often used when comparing fitness for different strains of the model yeast Saccharomyces cerevisiae. For stress survival assays, yeast stress resistance is measured using an ordered survival score that ranges from 0 (no growth) to 4 (confluent growth). Traditional approaches to analyze this type of data either treats data as a nominal categorical variable or as a continuous numerical variable. These approaches risk loss of information or violation of testing assumptions. In contrast, cumulative logit ordinal regression uses the information contained in the order …

Physiological And Molecular Responses Of Diverse Rice Genotypes Under Drought Stress, Huda Mohmmed Alshaya

Graduate Theses and Dissertations

Climate change-induced drought stress is a significant constraint on global rice (Oryza sativa L.) production, threatening food security. This study evaluated the drought resilience of 15 diverse rice genotypes from the USDA mini-core collection under field, greenhouse, and osmotic stress conditions. Field trials assessed reproductive-stage drought tolerance based on panicle length (PL), number of spikelets per panicle (NSP), and spikelet sterility (SS). Greenhouse experiments examined moisture retention at the vegetative stage. Significant genotypic variation was observed, with genotypes 310724, 310779, 311181, 311603, 311793, and Vandana exhibiting drought tolerance through stable PL and SS. Additionally, genotypes 310100, 310428, 311255, N22, …

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 …