Life Sciences Commons^™

Application Of Artificial Neural Network Algorithms For Irrigation Scheduling, Lisa Umutoni

All Dissertations

Neural networks have been extensively used in predicting soil water tension for improved irrigation scheduling and management. However, their lack of interpretability constrains their efficacy in grasping the nuanced patterns prevalent in soil water tension time series data. The first goal of this research was to develop interpretable deep neural network models for soil water tension prediction across multiple soil depths (0.15m, 0.3m, 0.46m and 0.6m) and prediction horizons (1h, 6h, and 12h). The Neural Hierarchical Interpolation for Time Series (N-HiTS) and Neural Basis Expansion Analysis Time Series (N-BEATS) models were used in this research. Historical soil water tension data …

Factors Influencing Swift Fox Reintroduction Success To Fort Belknap Reservation, Montana, Dana Nelson

All Dissertations

Reintroductions are an important conservation tool for reestablishing wildlife populations, and studying the factors influencing reintroduction outcomes is important to improving success rates over time. Swift fox are a small canid native to the short- and mixed grass prairies of western North America that have experienced severe population declines due to habitat loss and poisoning in the late 1800s. While swift fox now occupy approximately 40% of their historic range, reintroduction to northern Montana may promote the species’ long-term persistence, encourage connectivity in an existing range gap, and return species to areas where it is culturally significant. We studied the …

A Convergent Mixed Methods Study Of The Social Studies Academy In South Carolina Middle Schools, Audie Cherry

All Dissertations

There is a global labor shortage in the agricultural industry and middle school is a critical time to get students serious about career decision making. The Studies of Occupations, Culture, and Innovations toward Agricultural Literacy (SOCIAL) Studies Academy is a high impact professional development program in South Carolina that provides experiences and for middle school social studies teachers (N = 12) to become more suited to teach their standards associated with the agricultural sciences with hopes of encouraging more students to pursue agricultural careers. This study was a mixed-methods convergent parallel design that examined 1) Academy Fellows (n = 4) …

Changing Globally, Acting Locally: Responses Of Coastal Plant Functional Traits To Global Change Are Mediated By Biotic And Abiotic Interactions., Shannon L. Walker

Electronic Theses and Dissertations

We live in a time of rapid global change with substantial consequences for planet-wide functioning. Local ecosystems reflect this change, yet we struggle to predict their responses. Coastal ecosystems, like dune and interdunal wetlands, have declined rapidly and predicting their responses to global change is essential for future management. Functional traits may be particularly informative as they drive species and ecosystem responses and can provide generalizable findings. This dissertation investigates how global change, especially anthropogenic nitrogen (N) enrichment, interacts with abiotic and biotic factors to affect coastal sand dune and interdunal wetland plant functional traits. First, I used a long-term …

Ecosystem Services Of Urban Green Spaces In Louisville, Ky., Julia Kachanova

Electronic Theses and Dissertations

Accelerating urbanization poses critical challenges to urban green spaces (UGS), vital for ecological balance and human health. Rapid development often results in fragmented habitats, biodiversity loss, and diminished ecosystem service delivery. There is an urgent need to explore and evaluate novel strategies capable of enhancing urban resilience, such as implementing urban orchards, and managing existing parks and gardens in sustainable ways. This dissertation explores how different forms of urban green spaces (UGS) contribute to the provision and maintenance of critical ecosystem services that support human well-being and urban biodiversity. By analyzing UGS impact on ecosystem service provisioning and long-term sustainability, …

Linked Lives In The Riverbed: Integrating Fish Host Dynamics, Community Structure, And Demography For Freshwater Mussel Conservation., Jonathan Patrick Frommeyer

Electronic Theses and Dissertations

Freshwater mussels are long-lived benthic invertebrates that play key roles in nutrient cycling, water filtration, and habitat stability in rivers and streams. Despite their ecological importance, they are among the most imperiled faunal groups in North America, with their persistence increasingly threatened by environmental degradation and disruptions to host–parasite dynamics. This dissertation integrates host ecology, community structure, and demographic modeling to assess population viability and guide conservation priorities for mussel species in Kentucky river systems. The first chapter introduces the ecological context and conservation urgency surrounding freshwater mussels. In particular, emphasizing the need for multi-scale approaches to understand how parasitic …

The Influence Of Psychological, Biological, And Social Determinants On Disordered Eating Behaviors Among U.S. Young Adults: Evidence From Nhanes 2015-2018., Samantha Kaye Gerbine

Electronic Theses and Dissertations

Disordered eating behaviors (DEBs) are influenced by biological, social, and psychological factors, yet research often narrowly focuses on White, college-aged women. This study assessed the predictors and prevalence of DEBs in a nationally representative sample of U.S. young adults using data from the 2015–2018 National Health and Nutrition Examination Survey (NHANES). Survey weights were applied to generate national estimates. Descriptive statistics characterized the sample, and logistic regressions tested biological, social, and psychological predictors of DEBs. A composite risk score was developed using variables retained in the final model. The unweighted sample (n = 1,062) represented 64 million U.S. young adults. …

Blackberry Long-Cane Cold Storage And Forcing Strategy Effects On Flower And Fruit Development, Leala Machesney, Ryan Dickson, Amanda Mcwhirt, Margaret L. Worthington, Stephanie E. Burnett

Horticulture Faculty Publications and Presentations

Blackberry (Rubus subg. Rubus) production using soilless culture and "long-cane" techniques offers growers the potential to achieve off-season harvests and increase yields. This study investigated the feasibility of achieving early spring harvests and high yields with four blackberry cultivars (Natchez, Ouachita, Prime-ArkVR Freedom, and Prime-ArkVR Traveler) grown using long-cane techniques and six different cold storage and forcing environment strategies. Long-cane blackberry plants were container-grown outdoors during 2020 and were overwintered either at an outdoor nursery or in a cold storage facility (4 degrees C). Dormant plants were then forced the following spring at the outdoor nursery location or in a …

The Influence Of Retail Display Conditions On Ground Beef Quality And Palatability, Sarah Lynn Shoup

Graduate Theses and Dissertations

The objectives of these studies were to evaluate the impact of retail display case type and muscle type on meat quality attributes, including color, lipid oxidation, texture, and volatile compound profiles, as well as to assess economic implications based on retail color degradation. Case type effects were further evaluated by considering environmental factors such as temperature, air velocity, and relative humidity and their influence on the shelf life of beef patties. An economic analysis was also conducted to estimate the value of patties based on a* (redness) scores at different points during retail display. In Study 1, differences in L* …

Hepatic Lipid Metabolism Of High And Low Water-Efficient Broiler Lines Under Heat Stress, Maria Fernandez Cuadrado

Graduate Theses and Dissertations

Heat stress (HS) is one of the most critical environmental challenges negatively impacting global poultry production, significantly compromising broiler performance, welfare, and economic viability. Specifically, heat stress profoundly disrupts physiological and metabolic processes, including hepatic lipid metabolism. Two broiler lines were divergently selected for high (HWE) or low (LWE) water efficiency. Heat-stressed HWE birds showed reduced fat content compared to their LWE counterparts, and HS reduced abdominal fat content in both lines. The purpose of this study was to determine the difference in underlying molecular mechanisms involved in this divergent fat content between the lines. Day-old chicks were placed in …

Performance And Feasibility Of Pasture Rangeland And Forage Insurance In The Delta Region, Walker Bradley Davis

Graduate Theses and Dissertations

Despite being available nationwide since 2016, enrollment in Pasture, Rangeland, and Forage (PRF) insurance remains low in many regions of the country. The program's performance also presents regional discrepancies, with loss ratios varying significantly. Studies that have simplified the complexity of interval selection for producers have been shown to positively affect PRF enrollment. Such studies remain limited in several forage-producing areas. This study aims to address the lack of information in Arkansas specifically. Arkansas has among the nation's lowest participation rates and loss ratios. Low loss ratios signal that participants pay more in premiums than received in indemnities and may …

Impact Of Lighting Wavelength On Broiler Behavior, Health, And Performance, Angela Perretti

Graduate Theses and Dissertations

Lighting influences broiler production, health, and behavior. Due to their advanced visual system, avian species perceive a wide spectrum of light. The objective of this study was to investigate the effects of white (W, 350 to 780 nm) blue (B, 450 nm), and green (G, 560 nm) light on broiler production, processing performance, activity, fear, stress, blood cell profiles, tibiotarsi (tibia) morphology, and depth perception. Day-of-hatch by-product chicks from a Cobb 500 female line (N=600) were randomly assigned to 12 pens (N=4 treatment replicates). Body weight and feed consumption were recorded on day (D) 0, 14, 28, and 41, and …

The Bacteria Who Lived: Uncovering And Mitigating The Persistence Of Pathogens In Low-Moisture Food Processing, Kavita Shripati Patil

Graduate Theses and Dissertations

Low-moisture food (LMF) processing environments pose a persistent food safety risk due to Salmonella survival and harborage on surfaces. This work investigates persistent bacterial populations (PBPs) in LMF production environments, focusing on identifying a suitable surrogate and evaluating sanitation strategies. Three potential surrogates, Escherichia coli MP 26, Enterococcus faecium, and Pediococcus acidilactici, were compared to Salmonella PBPs formed in nonfat dry milk (NFDM) on stainless steel coupons stored at 25°C under 30% or 70% relative humidity (RH) using two different inoculation methods. E. faecium showed survival patterns most similar to Salmonella, with no significant differences in log reductions (p > 0.05), …

Effects Of Flavonoids On Reducing Colon Cancer Risk Via Macrophage Polarization, Gracien Jules

Graduate Theses and Dissertations

Colorectal cancer is one of the most fatal diseases in the United States. Chronic tissue inflammation can cause cell proliferation, which leads to tumor formation and cancer development. Macrophages are responsible for maintaining tissue homeostasis and for inflammatory responses. M1 macrophages exhibit proinflammatory responses while M2 macrophages exhibit anti-inflammatory responses. Imbalance between M1 and M2 macrophages is closely related to inflammation-associated disease development. The anti-inflammatory effects of apiaceous vegetable constituents, specifically flavonoids, have been studied for their preventative effects towards reducing disease risk. However, sufficient evidence is lacking on the mechanisms by which flavonoids impact M1/M2 macrophage polarization. RAW 264.7 …

Adiponectin-Regulated Macrophage Responses In Aspergillus Fumigatus Infection: Mechanisms Of Uptake And Killing, Sri Harshini Goli

All-Inclusive List of Electronic Theses and Dissertations

Invasive aspergillosis (IA), caused by Aspergillus fumigatus, is a life-threatening infection in immunocompromised individuals, necessitating novel host-directed therapies. Macrophages are pivotal in antifungal defense, yet their function can be dysregulated; the influence of the adipokine adiponectin (APN) on this process is not fully understood. This thesis investigated the role of APN signaling in alveolar macrophage (AM) and bone marrow-derived macrophage (BMDM) responses to A. fumigatus and assessed the therapeutic potential of the APN receptor agonist, AdipoRon. Initial studies revealed that genetic deficiency in APN or its receptors renders AMs intrinsically pro-inflammatory and significantly impaired fungicidal activity against A. fumigatus. Subsequent …

Dermatoglyphic Fluctuating Asymmetry In Schizotypy, Marcus R. Thomas

All-Inclusive List of Electronic Theses and Dissertations

Schizotypy has been linked with many of the proposed endophenotypes of schizophrenia, but research is limited on the relationship between schizotypy and dermatoglyphic fluctuating asymmetry. The present study sought to examine relationships between schizotypy, dermatoglyphic fluctuating asymmetry, handedness, and season of birth. 146 undergraduate students were identified as schizotypes (n = 52) or controls (n = 94) based on the Multidimensional Schizotypy Scale and had their finger and palm prints collected along with completing additional measures of schizotypy and handedness. Schizotypes did not exhibit a greater degree of dermatoglyphic fluctuating asymmetry, negative schizotypy was associated with increased absolute finger ridge …

Applying Transcriptomics For Technology Development And Conservation In North American Marine Organisms, Cory Von Eiff

Dissertations

RNA biology is a rapidly expanding field, with many avenues of discovery among marine organisms. In this study, we analyze both mollusks and sawfish. First, we perform an evaluation of sRNA biogenesis pathways throughout Mollusca, with emphasis on the easter oyster, Crassostrea virginica. Understanding these molecules prescribes RNAi-based gene silencing approaches, benefiting genetic investigation and biotechnology. Similar to other animal groups, mollusks have conserved microRNAs (miRNAs), with some shared with ecdysozoans and deuterostomes; however, there is no evidence of an endogenous small interfering RNA (siRNA) pathway. These results suggest that long double-stranded RNA (dsRNA)-based RNAi is not appropriate for gene …

The Inside Scoop: Elucidating The Three-Way Relationship Between Schistosoma Mansoni, The Gut, And Vaccines, Mariam A. Mhanna

Biomedical Sciences Theses & Dissertations

Schistosomiasis is a neglected tropical disease that affects over 250 million people worldwide. This blood fluke infection burdens communities and areas with limited to no access to clean fresh water. When a host is exposed to cercariae, the infectious agent, in a body of water, it matures in the host’s circulation into adult female and male worms. Copulated adult worms migrate to the mesentery, in the case of Schistosoma mansoni, and produce eggs that can cross the intestinal barrier and get excreted in the feces to continue the lifecycle. The effects of S. mansoni infection on the host …

Eccentric Hamstring Strength And Acl Injury Risk In Ncaa Division I Female Field Hockey Athletes, Killian Patrick Ferrell

Exercise Science Theses & Dissertations

Anterior cruciate ligament (ACL) injuries remain a pervasive issue in female collegiate athletics, particularly in sports demanding frequent decelerations, cuts, and high-speed movements such as field hockey. Despite the high injury burden, limited research has investigated biomechanical and workload-based risk factors specific to NCAA Division I female field hockey athletes. This study aimed to evaluate the relationship between changes in eccentric hamstring strength and movement load metrics with changes in a composite ACL Risk Index. The sample included nine NCAA Division I female field hockey players who completed a 13-week offseason strength and conditioning program. Eccentric hamstring strength was measured …

Evaluating Quadrupedal Locomotion In Bats: A Geometric Morphometric Comparison Of Vertebral Adaptations Across Mammals, Jessica Upham

Electronic Theses and Dissertations

Flight is the primary locomotion of bats, while quadrupedal locomotion is not often observed and is widely variable among bats. Frugivorous bats in Pteropodidae are more efficient climbers than frugivorous bats in Phyllostomidae and insectivorous bats in Vespertilionidae, while phyllostomids and vespertilionids are better at walking on horizontal surfaces. The aim of this study is to investigate whether bats with differing modes of nonflight locomotion also exhibit disparity in thoracolumbar vertebral morphology. Using geometric morphometrics, we compared the thoracolumbar vertebral shapes of these bat families with other terrestrial and arboreal mammals. The results revealed distinct vertebral shapes among bat families …

Cattle Regenerative Grazing Effects On Bat Activity In Southern Appalachia, Seth Morelock

Electronic Theses and Dissertations

Livestock farming accounts for about 70% of agricultural activity, with continuous grazing as the dominant conventional practice. However, this method often degrades biodiversity and ecosystem health through overgrazing. Regenerative grazing practices offer a potential ecologically sustainable approach to cattle management. Insectivorous bats are known to use agroecosystems for foraging and roosting habitats, offering an opportunity to assess their response to regenerative grazing. Using passive acoustic monitors, we evaluated the response of bats to cattle within regenerative grazed farms in East Tennessee, USA. Overall bat activity declined when cattle entered and exited paddocks, except for the tri-colored bat (Perimyotis subflavus …

The Effects Of Off-Season Evidence-Based Training Block Periodization Program On The Performance Of Soccer Athletes In A Di School: An Exploratory Study, Ibrahim F. Almughathawi

Electronic Theses and Dissertations

The investigators explored the effects of a two-year evidence-based block periodization strength training program on performance outcomes in NCAA Division I male soccer athletes. The investigators aimed to examine longitudinal changes in body composition, explosive strength, and match-play physical demands, as well as the associations between field-based performance assessment and GPS-derived metrics. Using a retrospective design, data were drawn from a research data repository for athletes who participated in a long-term sport science monitoring program under the same head coach and training conditions. Performance measures included vertical jump assessments (static and counter movement jumps under bodyweight and external load), isometric …

Investigating The Impact Of Psychoactive Plant Alkaloids On Bumblebee Behavior, Skylar Mathieson

Electronic Theses and Dissertations

The relationship between plants and their pollinators is often framed as a food-for-service exchange in which plants provide pollinators with nutrients in exchange for transport of their gametes. However, in addition to essential nutrients, many floral rewards (nectar, pollen) also contain defensive toxins such as alkaloids, with largely unexplored consequences for plant-pollinator interactions. I investigated how three psychoactive and addictive plant alkaloids — caffeine, nicotine, and morphine — affect foraging behavior in generalist bumblebees (Bombus impatiens) using robotic flowers. Each of these chemicals affected pollinator foraging behavior, influencing the number and duration of their visits to flowers in …

Investigating The Multiple Enzyme Complex In The Carotenoid Biosynthesis Pathway, Mercy Mormor

Electronic Theses and Dissertations

In nature, plant carotenoids are 40-carbon isoprenoids with polyene chains that may have double bonds. They are vital components of all photosynthetic organisms, playing several roles in the plant cell, including photosynthesis, pigmentation, phytohormone synthesis, signaling and photoprotection. In this study, we investigated protein-protein interactions among key enzymes involved in the carotenoid biosynthesis pathway using the Bimolecular Fluorescent Complementation (BiFC) assay. Our results revealed several interactions that suggest a coordinated regulation of enzymatic activity within this pathway, highlighting potential regulatory complexes that influence carotenoid production. The study also highlights the pivotal role of Zeta-Carotene Isomerase (Z-ISO) as a key regulatory …

Drivers And Consequences Of Changes In Nectar Microbiome Composition Across Spatial And Biological Scales, Daniel A. Barker

Electronic Theses and Dissertations

Microbial communities inhabiting floral nectar, known as the nectar microbiome, are important mediators of plant-pollinator interactions. However, the ecological and environmental factors that shape the composition of these microbial communities remain poorly understood. While previous studies have examined the effects of a few microbial groups, typically independent of one another, on one plant or pollinator species, this dissertation takes a wide-scale approach to explore how abiotic conditions and biotic interaction’s structure microbial communities within floral nectar. Furthermore, I also quantify how variation in microbial richness and identity influences pollinator behavior and plant reproductive success.

This dissertation shows that microbial abundance …

Hierarchy In Sensation: Exploring The 40 Hz Auditory Steady State Synchrony In The Primary Auditory And Prefrontal Association Cortices, Deepshila Gautam

Electronic Theses and Dissertations

Auditory processing begins in the cochlea and ascends through brainstem relays to the cortex, where sound features with increasing complexity are encoded. The 40 Hz auditory steady-state response (ASSR) reflects induced gamma synchrony shaped by local cortical circuit dynamics. Disrupted 40 Hz ASSR is a consistent finding in schizophrenia, linked to N-methyl-D-aspartate receptor (NMDAR) hypofunction in inhibitory interneurons, making it a promising translational biomarker. While multiple ASSR generators have been identified, it is not known if these are redundant or represent unique activity. This dissertation investigates regional differences in 40 Hz ASSR across two principal generators: the primary auditory cortex …

Effect Of Moderate Decrease In Contractility On Epithelial Cell-Cell Contacts Under External Stretch, Saika Sharmin

Mechanical & Aerospace Engineering Theses & Dissertations

Epithelial tissues are characterized by extensive cell–cell contacts and often subject to stretch during normal function. Cell-cell contact adhesion strength maintains mechanical continuity from cell to cell. Mechanical forces exerted by cells via actomyosin contractility are known to strengthen cell-cell adhesions to a certain extent. While it is known that a large decrease in contractility causes cell-cell contact rupture due to weakened adhesions, it is unclear how a moderate reduction in contractility affects cell-cell junction stability. Here, we studied how a moderate inhibition of non-muscle myosin II (NMII) affects the integrity of epithelial cell-cell contacts, especially when subject to the …

Sex Differences In The Risk Of Developing Alzheimer Disease, Cognitive Trajectories, And Relationships Between Cognition And Pathological Burden, Carling G. Robinson

Arts & Sciences Graduate Student Theses and Dissertations

Prior work suggests females may develop Alzheimer disease (AD) dementia at a higher rate than males, and that this effect may interact with apolipoprotein (APOE) ε4 genotype. However, this work has often been limited by imprecise clinical diagnoses and a lack of AD biomarkers. In addition to the frequency of dementia, there are mixed reports on whether sex impacts rates of cognitive decline. Further, females consistently exhibit greater accumulation of AD pathological biomarkers, particularly tau, than males. It has been theorized that females initially demonstrate resilience to AD pathology, maintaining cognitive functioning longer than males, but experiencing a steeper cognitive …

A Note On Psoloessa Texana And Achurum Sumichrasti (Orthoptera: Acrididae: Acridinae) From Louisiana, Jovonn G. Hill

Midsouth Entomologist

During a 2024 survey in Kisatchie National Forest, Louisiana, Psoloessa texana and Achurum sumichrasti were collected, representing new state records. No prior records of P. texana exist for Louisiana, and while A. sumichrasti has been observed and reported online, no specimens were previously documented. These findings extend the known range of P. texana by ~320 km and suggest a broader distribution for A. sumichrasti. Their presence in xeric savannas may reflect Pleistocene-era disjunctions. With these additions, Louisiana’s documented grasshopper fauna increases to 41 species.

Bioassay To Evaluate Resistance Levels In Tarnished Plant Bug (Hemiptera: Miridae) Populations In Alabama To Common Cotton Insecticides, T. J. Douglas, K. Kesheimer, A. Jacobson, S. Brown, F. R. Musser, L. S. Catchot, S. H. Graham

Midsouth Entomologist

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), has emerged as the major insect pest of cotton in the mid-southern United States following the eradication of the boll weevil and the introduction of genetically modified Bt cotton for caterpillar pests. The objective of this study is to evaluate tarnished plant bug resistance to the five most common insecticides used for control across six distinct growing regions. Glass-vial bioassays were used to evaluate resistance of field populations in a laboratory setting. Elevated levels of resistance of tarnished plant bug to bifenthrin and, to a lesser degree, imidacloprid have been reported …