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Computational Fluid Dynamics Based Optimization Method Applied To Hydrokinetic Turbine Devices, Stuart Glenn Fletcher

Graduate Theses and Dissertations

This thesis presents a computational investigation of optimal kinematic operating parameters governing various hydrokinetic turbines (HKT) systems for the use of power generation within river and tidal environments. Two separate studies are performed. The first study investigates optimal cycle parameters for simple and complex kinematic modes governing the motion of oscillating foil energy harvesters (OFEH). An iterative gradient-ascent optimization method is used to search for local efficiency optima based on an initial set of kinematic parameters. To search the operational space for up to eight degrees of freedom (DOF), a maximin space filling condition was implemented to efficiently compute initial …

Evaluating The Effectiveness Of An Air Purification System In Reducing Bacterial Chondronecrosis With Osteomyelitis Lameness In Broiler Chickens, Abdulaziz Ali Alqahtani

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis (BCO) is the primary cause of lameness in commercial broiler production and has a profound impact on animal welfare and cost-effectiveness. The purpose of this experiment was to examine the effect of an air purification system on mitigating BCO lameness in broiler chickens. One thousand eight hundred broiler chicks were reared in two side-by-side research barns. Eight air filtration units were installed in one building, and none in the other. Treatment groups in both houses included positive control birds on wire flooring to induce BCO, as well as negative control, feed additive, vaccination, and a combination …

Cattlefever: An Automated Cattle Fever Estimation System, Trong Thang Pham, Ethan Coffman, Beth Kegley, Jeremy G. Powell, Jiangchao Zhao, Ngan Le

Electrical Engineering and Computer Science Faculty Publications and Presentations

Farmers face the critical challenge of monitoring cattle well-being for both ethical and economic success, relying on signals like body temperature and facial expressions to assess their animals' health. However, these indicators have traditionally relied on human observation with manual measurement, which is time-consuming and subjective. Despite this clear need, no automated system currently exists for monitoring cattle body temperature, and available datasets remain limited in scope. To address these challenges, we make two key contributions: (i) We introduce CattleFace-RGBT, a novel RGB-Thermal (RGB-T) Cattle Facial Landmark dataset consisting of 2,300 paired RGB and thermal images (4,600 images in total), …

Anti-Inflammatory Effects In Apio Tuber, Jeehye Seo, Oluwatobi Amusat, Yu-Yun Wang, Annegret Jannasch, Sun-Ok Lee

Food Science Undergraduate Honors Theses

Inflammation is a crucial component of the body’s defense system but can lead to chronic diseases when uncontrolled. Diets rich in anti-inflammatory compounds are recognized as an effective strategy for mitigating chronic inflammation. This study investigated the anti-inflammatory potential of Apio (Arracacia xanthorrhiza), an underutilized Andean tuber. The goal of this study was to explore the health-promoting properties of Apio tuber, which could expand its commercial value to support local farmers and contribute to more sustainable agricultural practices.

Phenolic compounds were extracted from white (WAT) and yellow Apio tuber (YAT), and Total Phenolic Content (TPC) and antioxidant capacity …

Freshwater Turtle Assemblages And Densities In Agricultural Ditches And Aquaculture Ponds Of Eastern Arkansas, Andrhea D. Massey, John D. Willson, Brett A. Degregorio

Biological Sciences Faculty Publications and Presentations

The Mississippi Alluvial Plain (MAP) of Arkansas is a landscape where many wetlands have been altered for use as aquaculture ponds or agricultural ditches. Commercial harvest of freshwater turtles within the MAP is not restricted or limited, with reported harvest numbers for 2019 alone exceeding 4000 for spiny softshell turtles (Apalone spinifera) and 39,000 for red-eared sliders (Trachemys scripta elegans). Herein, we attempt to provide baseline estimates of freshwater turtle densities and community composition in aquaculture ponds and agricultural ditches of eastern Arkansas, the habitat types most frequently trapped by commercial harvesters. We used a capture-mark-recapture approach over 3 summers …

Broiler Responsiveness To Dietary Amino Acid Density In A Commercial Setting, Virginia Slick

Graduate Theses and Dissertations

The majority of research assessing the amino acid responsiveness in broilers has been conducted in experimental designs utilizing pens that contain 12 to 25 birds with high replication. While this trial design is beneficial as a way to perform high replications with multiple treatments in a way that is both economically and spatially feasible, it may not accurately translate to a rearing environment more similar to that of commercial open floor housing. This research was conducted to determine if the effects of lysine driven amino acid density diets that have been found in the traditional floor pen setting correlate to …

Characterization Of Water Intake And Water Conversion Ratio For Male And Female Broilers From Four Commercial Broiler Lines Reared To Eight Weeks Of Age, J.Z. Hiltz, C.W. Maynard, T.W. Tabler, M.A. Maquesda, K.M. Shafer, K.B. Nelson, M.T. Kidd, N.B. Anthony, S.K. Orlowski-Workman

Poultry Science Faculty Publications and Presentations

Increased interest and investigation into the sustainability of broiler production has led to a need for reliable and repeatable means to measure water intake and its conversion rate into salable meat. Therefore, a study was conducted to characterize the water intake and water conversion ratio (WCR) of male and female broilers from four modern broiler strains. Two of these lines represented fast growing broiler strains (FGB A and FGB B) targeting a small bird market and two represented high yielding broiler strains (HYB A and HYB B). Three replicates of 25 sexed broilers from each line were placed into 24 …

Assessing Native Tallgrass Prairie Species As Main Roadside Vegetation In Arkansas, Sarah Paschal

Graduate Theses and Dissertations

Tallgrass prairies are among the most endangered ecosystems in North America, with Arkansas having lost over 99% of its native grasslands. This research evaluated the potential for using native tallgrass prairie species in Arkansas roadside vegetation. Two field experiments were conducted from 2022 to 2024. The first assessed seven native seed mixtures at three roadside locations (Clarksville, Huntsville, and Newport). Seed mixture composition significantly influenced establishment outcomes, with early-establishing forbs such as black-eyed Susan, partridge pea, and Illinois bundleflower performing well, though establishment varied by location. A second trial compared planting date (Autumn, Winter, Spring) and planting method (broadcast, drill …

Perception Of Drinking Water Quality Among Arkansas Residents, Kolade Olawale Olatunde

Graduate Theses and Dissertations

Objective: Perceptions of drinking water quality influence public trust, water consumption behaviors, and the willingness to invest in infrastructure improvements. Despite the importance of safe drinking water, regional and socio-economic disparities impact how residents perceive their tap water and their readiness to pay for enhancements. While past research indicates that negative views of tap water quality have resulted in behavioral changes, the connection between perception and actual household water usage remains ambiguous. This study aims to investigate how perceptions of drinking water quality differ across regions in Arkansas and how residents are willing to invest in quality improvements. Method: A …

Optimizing Cobb Mx X 500 Broiler Diets Through The Investigation Of Lysine And Energy Synergies, Soybean Processing “Add-Backs” Ingredients, And Soybean Genotype Amino Acid Selection, Savannah Caroline Wells

Graduate Theses and Dissertations

This dissertation explored strategies to optimize Cobb MX x 500 broiler chicken nutrition by investigating lysine and energy synergies, the utilization of soybean processing by-products (“add-backs”), and soybean genotype selection for enhanced amino acid composition. Three independent but complementary research objectives were pursued to improve feed efficiency, sustainability, and cost-effectiveness in modern broiler production. The first objective assessed the interactive effects of dietary lysine and metabolizable energy (ME) on the performance and carcass traits of Cobb MX × 500 broilers. Using a central composite design, nine dietary treatments were formulated across multiple feeding phases. Results demonstrated that broiler performance responded …

Increasing Soil Health In Zero-Grade, Flood-Irrigated Rice In Eastern Arkansas, Hannah Elizabeth Vickmark

Graduate Theses and Dissertations

In an effort to build and maintain soil health and sequester soil C, many producers and researchers are turning towards regenerative management practices in agricultural systems, such as reduced tillage or no-tillage (NT), the implementation of winter cover crops (CC), and the use of organic or green manures, such as biochar. However, little research is being conducted on the long-term soil health and agronomic benefits of these practices in a flood-irrigated rice (Oryza sativa L.) production system. Three replications of seven treatment combinations were applied to 6.1 x 30.5 m rice plots. Baseline soil health properties were quantified at six …

Emotion Analysis And Neural Language Models For Classification, Andrew Mackey

Graduate Theses and Dissertations

Emotion analysis is a branch of artificial intelligence and natural language processing focused on recognizing emotions hidden throughout various forms of digital data, including text, images, and multi-modal representations. In this dissertation, we present four published and planned works that investigate different methodologies for natural language analysis tasks using deep learning techniques. The first published work we present considers the task of identifying fake news using various text and emotion representations. We demonstrate that emotion representations combined with word embedding techniques can improve the accuracy of fake news classification. Our second published work further investigates the fake news classification task …

Hyperspectral Indicators And Characterization Of Glyphosate-Induced Stress In Common Lambsquarters (Chenopodium Album L.), Mario Andrés Soto Valencia

Graduate Theses and Dissertations

Hyperspectral sensing enables detection of herbicide stress in weeds, but practical use requires strategies for redundancy control, rating variability management, and evaluator bias mitigation. This thesis evaluates common lambsquarters (Chenopodium album) under glyphosate exposure, aiming to identify key wavelengths, construct vegetation indices, and improve injury modeling. Greenhouse experiments used dimensionality reduction methods (principal component analysis, Relief F, Bayesian discriminant analysis) to isolate 34 unique wavelengths from about 3,200 bands. Calibration data were collected 14 days after treatment (DAT) to support wavelength selection and model development, while data from 27 DAT were used for independent validation. Class comparisons across six statistically …

Novel Approaches To Disinfecting Poultry Processing Wastewater For Reuse, Seth Olorunmijuwonlo Adesope

Graduate Theses and Dissertations

Water is an essential resource used in poultry processing, generating large volumes of foodborne pathogen-rich wastewater posing treats to public health. Treating poultry processing wastewater (PPW) is crucial for safe water reuse and sustainable development. Conventional disinfection methods like aerobic digestion and chlorination, although effective, impose considerable operational cost and generate harmful by-products. Integrated recycling systems such as advanced oxidation processes (AOPs) which destroy micro-organisms through the generation of reactive oxygen species (ROS) present a promising opportunity for enhancing resources and sustainability. This study investigated the use of photo-electrochemical (PEC), specifically by combining electrochemical (EC) and photochemical (PC; Photosensitizer and …

Solar Powered Conservation: The Effects Of Solar Photovoltaic Facilities On Avian Community Composition, Michael Christopher Ferrara

Graduate Theses and Dissertations

The expansion of solar photovoltaic energy infrastructure is transforming landscapes worldwide. Increasingly, facilities are planted with native vegetation, yet how vegetation characteristics and landscape variables shape wildlife communities in solar facilities remains poorly understood. Because avian populations have been in decline and are sensitive to habitat changes, understanding how solar facilities influence avian communities is important. In Chapter 1, we used autonomous recording units, local vegetation measurements, and land use and land cover data to quantify how avian community occupancy is influenced by solar cover in solar facilities and comparable reference sites. We used a Bayesian multi-species occupancy model to …

Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright

Graduate Theses and Dissertations

Abstract Grassland agriculture is seen as a particularly sustainable form of agriculture. Many opportunities are known to use organic production methods or incorporate native warm-season grasses (NWSG) to accomplish both production goals and environmental or social outcomes. Environmental concerns have led some practitioners to question the use of organic methods to establish NWSG. As limited work has been accomplished in the northern bermudagrass belt, this project sought to compare organic establishment strategies for common NWSG species. A field trial conducted at the USDA ARS Dale Bumpers Small Farms Research Center in Booneville, AR found that NWSG establishment success in the …

Ecological Elemental Homeostasis And Stoichiometric Shifts: Biotic Responses To Ionic And Viral Stress, Samuel Anthony Tooru Dias

Graduate Theses and Dissertations

Anthropogenic activities are reshaping the elemental composition of freshwater ecosystems, often creating stoichiometric imbalances that influence the growth, physiology and interactions of aquatic organisms. Ecological stoichiometric theory (EST) provides a framework for examining these changes by linking organismal elemental regulation to broader ecosystem processes. While traditionally focused on elements, such as carbon (C), nitrogen (N), and phosphorus (P), emerging stressors highlight the need to expand this framework to be more elementally inclusive for the examination of novel interactions. My dissertation integrates abiotic (salinization) and biotic stressors (viral infection) into an EST framework to evaluate how these factors alter elemental regulation …

There, But Not There: Pre-Service Teacher Identity And Transformation In The Internship Semester, Jacob G. Warren

Graduate Theses and Dissertations

This descriptive multiple-case study investigates how five secondary pre-service teachers constructed and negotiated their professional identities during the internship semester. Guided by a single overarching research question—How do pre-service teachers form and narratively negotiate their identities as educators within the liminal space of the internship?—the study conceptualizes identity as a dynamic, socially mediated, and storied process. Sociocultural theory and narrative identity theory provide the analytical framework, emphasizing development through interaction, participation, and reflective meaning-making. Participants were enrolled in a Bachelor of Arts in Teaching program and completed internship placements in middle and high school classrooms. Data were collected through pre-internship …

Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick

Graduate Theses and Dissertations

Anthropogenic climate change is projected to shift not only average temperatures across the globe, but also the amount of thermal variation experienced in the natural environment. Exposure to shifts in averages and a wider range of thermal experiences will cause shifts in wildlife behavior. In avian species, behaviors exhibited during reproduction have implications for the well-being of their offspring. Here, I explore specific incubation behaviors in four species: Scaled Quail (Callipepla squamata), Northern Bobwhite Quail (Colinus virginianus), Tree Swallows (Tachycineta bicolor), and Eastern Bluebirds (Sialia sialis). I examined constancy, or the percentage of time on the nest, and off-bout duration, …

Ring-Opening And Monofunctionalization Study On Spiro Cyclic Aminals And N, O-Acetals System Via Nitrogen-Centered Radical Intermediates, Chujun Zhou

Graduate Theses and Dissertations

The nitrogen-centered radical has been drawing increasing attention among researchers. Radical polarity is one of the key factors in studying nitrogen-centered radicals’ reactivity, and the functional groups attached to the nitrogen atom are of vital importance. Among different types of nitrogen-centered radicals, aminium radical and metal aminium radical are electrophilic due to the positive charge on the intermediate. The sulfonamide radical, amidyl radical, and cyanide amine radical are also electrophilic since the nitrogen is adjacent to electron electron-withdrawing group. The neutral amino radical, iminyl radical, masked nitrogen radical are nucleophilic because of the electron-donating groups. After classifying the nitrogen-centered radical, …

Using Color And Fluorescent Spectrometry As A New Rapid Cleaning Verification Method In Poultry Processing Plants, Clark Griscom

Graduate Theses and Dissertations

The poultry industry is expected to be growing at 3% in the total global market with the U.S. being the largest producer of poultry meat. Poultry processing plants are expected to produce 140 birds per minute with the potential of up to 175 birds per minute to meet the market demand. With the growing market and need for faster production, maintaining food safety needs to be a priority to ensure the safety of consumers. Over 9.9 million foodborne illness cases are reported each year in the United States. A change in food safety is needed, and one area lacking is …

Volume Status Detection With Integral Pulse Frequency Modulation Model Of Peripheral Venous Pressure, Jeremiah Rhys Wimer

Graduate Theses and Dissertations

This thesis studies the effectiveness of utilizing a modified integral pulse frequency modulation (IPFM) algorithm to synthesize peripheral venous pressure (PVP) waveforms for the detection of several physiological conditions using logistic regression. PVP waveforms are collected from 18 human patients and 4 porcine subjects. Human data are used to train models for determining the hypovolemic status of the patient, while the porcine data are used to train models for determining level of anesthesia and detecting internal hemorrhaging. In the human dataset, the waveforms collected from the 18 patients are classified into two groups according to serum chloride levels: resuscitated (≥100 …

“No Man Is An Island:” A Critical Discourses Analysis Of Newspaper Reporting On The Marshallese Community In Northwest Arkansas, Johana Vazquez

Graduate Theses and Dissertations

The aim of this study was to examine local newspaper coverage of the Marshallese community in Northwest Arkansas from 1998 to 2017 and analyze discourses that could be attributed to linguistic bias, stereotypes, and Pacific transnationalism. This analysis examines how marginalized immigrants are portrayed in local news coverage using a critical discourse analysis (CDA). The study analyzes the labels and metaphors used in the coverage of Marshallese immigration, adapts the Stereotype Content Model for a discourse analysis, and compares the experiences of Marshallese in the area with larger scholarly work on Pacific transnationalism. The researcher analyzed 11 published pieces from …

Next-Generation Salmonella Inactivated Vaccine Platforms And Phytobiotic-Modulated Immune Responses In Poultry, Santiago Uribe Diaz

Graduate Theses and Dissertations

Here, a comprehensive understanding of immune responses triggered by either a multimeric CD40 receptor-agonistic DNA aptamer-based or mannosylated chitosan-based Salmonella Enteritidis inactivated vaccine platforms, along with phytobiotic supplementation as an immune modulatory strategy in response to Salmonella lipopolysaccharides, is presented. This dissertation supports the development of next-generation Salmonella vaccine platforms that simultaneously stimulate both protective cell-mediated and humoral immune responses, while indicating the potential immunomodulatory effects of phytobiotics supplementation to reduce the immunological impact of Salmonella lipopolysaccharides in chickens. The first chapter describes that both vaccine platforms administered in broiler chickens initiated local inflammatory responses, recruiting heterophils and macrophages from …

Micro-Greens, Not Micro-Yellows: Evaluating Dehydration-Based Preservation Techniques For Reducing Foodborne Pathogens And Quality Preservation On Microgreens, Travis S. Sananikone

Graduate Theses and Dissertations

Microgreens are increasingly popular among consumers due to their high nutritional value. However, their limited shelf-life remains a significant challenge. To extend their usability, small-scale growers increasingly apply home preservation methods like warm air drying or freeze-drying. However, the effects of these methods on common foodborne pathogens are not well understood. Radish and alfalfa microgreens were inoculated with cocktails of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes 4b (ca. 8.0 log CFU/g). Treatments included dehydration in a commercial dehydrator, freeze-drying (-20°C, 24 h), and convective drying in an oven (60°C for 4 h), and convective drying in an oven …

Prevalence Of Cytauxzoon Felis In Ticks From South-Central Kansas And Northwest Arkansas, Nicole E. Mcilvain

Animal Science Undergraduate Honors Theses

Cytauxzoon felis is a protozoan that causes an often-fatal illness in felines known as cytauxzoonosis, or bobcat fever. Ticks are vectors of this pathogen, with Amblyomma americanum being the most common vector. Previous studies have noted a correlation between peak tick season and peak cytauxzoonosis diagnosis. For cytauxzoonosis, minimal treatments exist, and scientists have not found a cure, which is why focus needs to be on preventing disease. Knowledge on the prevalence of C. felis in different tick species helps veterinarians and pet owners be aware of the potential for their cat developing cytauxzoonosis if one or more ticks are …

Benefits Of Animal Assisted Therapy In Pediatric Inpatient Units: A Literature Review, Logan M. Shiflett

The Eleanor Mann School of Nursing Undergraduate Honors Theses

The purpose of this systematic review of literature was to establish if animal assisted therapy (AAT) is helpful in the reduction of stress for patients on pediatric inpatient floors. The PICOT question that led this review was: In pediatric patients, how does animal assisted therapy affect patient outcomes related to increased hospitalizations? The EBSCOhost database, as well as the Web of Science and CINAHL Complete information sources, were used to find relevant studies for this review that assessed the benefits and contraindications for AAT. Key terms such as “animal assisted therapy,” “pediatrics,” and “inpatient” were used to narrow down the …

The Genetic And Environmental Determinants Of Stress Resilience Across Model Systems, Carson Len Stacy

Graduate Theses and Dissertations

Survival in fluctuating environments demands that organisms effectively anticipate and respond to future challenges. This capacity is shaped by both genetic background and environmental context. In this dissertation, I apply a population aware lens to explore how genetic diversity and environmental conditions intersect to shape stress survival. Integrating functional genomics and transcriptomics in Saccharomyces cerevisiae (brewer’s yeast) and a vertebrate (common canary) system, I dissect gene-by-environment (GE) interactions that underpin resilience. First, I move beyond a single reference genome by using a pan-genomic CRISPR knockout screen to assess osmotic stress survival across diverse S. cerevisiae isolates. This analysis reveals a …

Effects Of Injectable Trace Mineral Timing On Calf Performance And Health Indicators, Marie E. Goulais

Graduate Theses and Dissertations

One hundred and fourteen calves (average BW= 224kg ± 89kg) were utilized to evaluate the effects of injectable trace mineral (ITM) administration on calf performance and health when administered pre-weaning and at weaning. Calves were blocked by sex, stratified by age, and randomly assigned to one of the following treatment groups: 1) no ITM injection (CON), 2) ITM administered 28 d before weaning (PW), or 3) ITM administration at weaning (WEAN). Calves were vaccinated against respiratory pathogens on D-28 and D0. At weaning, cattle were transported to a local auction market, held overnight and returned the following morning. Body weight …

Agricultural Practices’ Impact On Soil Health Indicators In Mid-South U.S. Crop Production Systems, Katherine Suzanne French

Graduate Theses and Dissertations

Soil health and regenerative agriculture are concepts gaining popularity across global agriculture systems. The effect of sustainable farming practices such as nutrient management, cover crops, adoption of no-tillage, and residue retention on crop yield, as well as environmental resilience, is increasingly being studied. This research aimed to evaluate the impacts of (i) cover cropping and nutrient management, and of (ii) soil sampling depth and timing on indicators of soil health in various mid-southern irrigated row crop systems. Soil health indicators like soil organic matter (SOM), carbon dioxide respiration (CDR), beta-glucosidase enzyme activity (BG), permanganate oxidizable carbon (POXC), and the soil …