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Under The Sea And Into The Future With Darwin, Verne, & Wells: Evolutionary Ideas In Early Science Fiction Literature And Atomic Age Adaptations, Suzette K. Forston

Theses and Dissertations

In the latter half of the nineteenth century, Charles Darwin's theories challenged traditional ways of thinking about the world so dramatically that his writings inspired the formation of a new genre: science fiction. Two pioneering authors, Jules Verne and H. G. Wells drew from Darwin's writings in their classic novels, 20,000 Leagues Under the Seas (1870) and The Time Machine (1895). Though the two authors are often compared because they were both early science fiction authors, they approached Darwinian theory in different ways. Verne uses a more extrapolative approach and focusing on specific details of Darwin's texts to tell a …

Chemically Mediated Communication In Mound-Building Termites, Sree Subha Ramaswamy

Theses and Dissertations

Nest-building in social insects requires layered communication to coordinate complex, functional structures for housing, protection, storage, and homeostasis. This is especially striking in mound-building termites, which construct and repair large mounds collectively despite lacking image-forming eyes. This thesis investigates how Odontotermes obesus achieves such coordination through chemical communication embedded in soil.

Using controlled two-choice assays with manipulated soils, I separated airborne volatile signals from contact non-volatile signals by baking to remove volatiles, a mesh assay that presented volatile cues without contact, and solvent extraction with reapplication of contact cues. I quantified responses in major-only, minor-only, and mixed groups at two …

Harnessing The Potential Of Biostimulants To Mitigate Drought And Heat In Soybeans, Vijaykumar Hosahalli

Theses and Dissertations

Drought and heat stresses during vegetative and reproductive stages cause yield losses up to 50% in soybeans. Biostimulants have potential to improve stress tolerance and enhance crop resilience, but selecting an effective product remains challenging due to the wide range of commercial options. This study aimed to identify suitable biostimulants that alleviate drought and heat stress during vegetative and reproductive stages. There was 64% and 76% reduction in stomatal conductance under vegetative and reproductive stage drought stress, respectively. Drought and heat stress during reproductive stages resulted in 44% and 36% reduction in total seed weight, respectively. Among biostimulants, treated check …

Transcription Fidelity In The Face Of Oxidative Damage, Eastilan Gyiwah Appiah

Theses and Dissertations

It is very important that the process of transcription is correctly carried out in the cell for the faithful expression of the genetic code. However, should mistakes happen, they can result in transcription errors which interfere with the protein-making machinery of the cell. This will result in accumulation of proteins and dysfunctional proteins that have the potential of causing diseases like Alzheimer’s. Oxidative damage caused by hydrogen peroxide is known to cause transcription errors in organisms like yeast. It is therefore important to investigate the extent to which hydrogen peroxide can damage cells.

Optical Trapping For The Study Of The Chemical And Physical Dynamics Of Single Particles, Yukai Ai

Theses and Dissertations

This dissertation explores the combined technique of optical trapping and Raman spectroscopy (OT-RS) to study the physical and chemical properties, as well as the dynamic surface changes, of single aerosol particles in air. The study covers a wide range of aerosol types, including bioaerosols (such as pollen, bacteria, and fungi), dust particles (such as black carbon, terrestrial, and extraterrestrial materials), and liquid droplets (such as sea-spray aerosols). The optical trapping system used in this work is based on the universal optical trap (UOT), which is capable of trapping and manipulating a wide variety of particle types. These include both transparent …

Determining The Toxic Threshold And Other Use Characteristics For Industrial Hemp Seed Oil Used For Wood Product Protection, Daylan M. Barnes

Theses and Dissertations

Plant-based wood treatments have been utilized for many years, with varying success. Oils such as those extracted from linseed (flax), tung, and hemp plants have been used for thousands of years as finishes on wood. These are all drying oils, which dry to a film when exposed to air. Hemp seed oil has a high fatty acid content and can take a long time to dry on wood products but is valued in woodworking for being easy to use, food-safe, and having little to no odor. In this study, cold-pressed hemp seed oil, blended with a soybean carrier oil, is …

Integrated Analysis Of Untargeted Liver, Serum Metabolome And Gut Microbiome Following Selenium Deficiency Diet In Selenoh Knockout And Wildtype Mice, Richard Eugene Baird

Theses and Dissertations

Selenoprotein H (SELENOH) is an oxidoreductase located in the nucleolus, and its biochemical levels decrease with selenium (Se) deficiency, as reported in mammalian research. This current investigation aimed to understand the impact of nutritional Se deficiency on gut microbial composition and metabolomic profiles. The Firmicutes/Bacteroidota (F/B) ratio, linked to various health conditions, was balanced for wildtype (WT) mice (1.06). In contrast, selenoh knockout (KO) mice associated with dietary Se deprivation had a significantly (p < 0.002) lower ratio (0.56), suggesting dysbiosis. It is believed that SELENOH levels decreased due to the Se deficient diet, and the selenoh KO mice exhibited alterations in microbial community composition and metabolite profiles, as supported by correlative analyses. With respect to the bacterial communities, significant differences between diets occurred for three taxa, including Akkemansia mucinphila, Bacteroides caecimuris, and Parabacteroides goldsteinii. Candida tropicalis, Malassezia restricta, and Cyberlindnera jadinii were three abundant fungal yeasts. Only Cyberlindnera jadinii exhibited significantly greater relative abundance between genotypes and was more abundant in the selenoh KO versus WT mice. Correlation analyses between bacterial and fungal taxa revealed both positive and negative relationships, but no specific trends were observed. The liver and serum metabolomic data contained similar amino acids, lipids, proteins, and carbohydrates. Using NMR spectroscopy, 112 liver metabolites were detected, while GC-TOF-MS analysis of the serum revealed the presence of 172, comprising both polar and nonpolar compounds. The metabolite levels varied significantly when analyzed using multivariate models such as PCA and PLS-DA (VIP scores), particularly for glucose, taurine, lactate, and UDP-glucose, which are associated with energy production and cellular health. Overall, the Se deficient diet had the most significant impact on the microbial community structure and the concentration of key metabolites within liver tissues and serum. Correlation analyses conducted across studies revealed significant linear relationships between metabolites and the microbiome. However, these differences were associated with bacterial and fungal taxa containing low relative abundances. Based on these findings, further investigation into the impact of SELENOH homeostasis on microbial and metabolite profiles should be conducted using selenoh KO mice under various nutritional Se dietary levels.

Fungal Resistance Of Citric Acid Crosslinked Chitosan Treated Wood, Samuel Jacob Barton

Theses and Dissertations

Chitosan (CH), a linear polysaccharide biopolymer derived from chitin, is known for its antimicrobial and antifungal properties. However, its natural hydrophilicity limits its application as a wood preservative. This study explores the crosslinking of chitosan with citric acid (CA) to improve its stability and hydrophobicity, aiming to enhance its efficacy as a wood preservative. The study investigates fungal resistance against Gloeophyllum trabeum (brown-rot) and Trametes versicolor (white-rot) fungi using the AWPA E-10 soil block test for pine and gum samples vacuum-treated and dip-treated with CH-CA concentrations (CH 6%/CA 3%, CH 4%/CA 3%, CH 2%/CA 3%, and CH 1.5%/CA 3%). The …

Variables That Affect Designers’ Use Of Edible Planting In Residential Landscape Design, Emily Margaret Butler

Theses and Dissertations

Edible landscaping or “foodscaping” has had a resurgence into the mainstream. Though many trailblazers aim to encourage edible landscaping through homeowners and renters, there seems to be a lack of initiative from designers. To identify the variables that can affect a designer’s use of edible planting in the residential Southeastern United States, research and statistical methods were employed. Beyond interviewing an expert in the field of edible planting in the residential space, a survey consisting of both Likert and open-ended questions was sent to licensed landscape architects in the Southeastern U.S. The survey was conducted using Qualtrics and analyzed using …

Influence Of Diverse Forage Environments On Honey Bee Colony Health, Angus Catchot Iii

Theses and Dissertations

Honey bees are important pollinators that face a multitude of stressors in their environment such as pathogens, parasite pressure, forage availability and pesticide exposure. This study examined how the makeup of different environments and the stressors related to those environments are affecting honey bee health in Mississippi. A field experiment was conducted during the first year of the study across four distinct landscapes ranging from intensively cultivated cropland to predominantly natural forage habitats to assess the impact of landscape availability on varying honey bee colony health parameters. Locations that had cultivated crops within foraging range produced more honey and brood …

Winter Waterfowl Forage Production In Managed Coastal Wetlands Of The South Atlantic Region: Improving Inputs For Bioenergetics Modeling Used In Regional Conservation Planning, Stephen Andrew Clements

Theses and Dissertations

Under the assumption that food is limiting to non-breeding waterfowl, Migratory Bird Joint Ventures frequently use daily-ration bioenergetics models to inform wetland conservation objectives. Two essential components of these models include estimates of energy supply (i.e., energetic density) of wetlands used by waterfowl and accurate spatial data layers to determine wetland area. Managed impoundments are important wetland resources for migrating and wintering waterfowl in the South Atlantic Region. However, there is little understanding of the energetic density available to waterfowl in these wetlands regionally, and until recently, a database of digitized impoundments was unavailable for developing a spatial data layer. …

Soil Ethics In Practice: Harvesting Conservation Choices Among Puerto Rican Coffee Farmers, Patricia Marie Cordero-Irizarry

Theses and Dissertations

Coffee farming in Puerto Rico has declined over recent decades, partly due to deteriorating soil quality. However, the decision-making process behind farmers’ adoption of soil conservation practices remains unclear, particularly the overlooked role of soil ethics, which emphasizes the moral principles guiding human relationships with the soil. This mixed-methods study examined coffee farmers’ adoption of soil conservation practices by integrating the Values-Beliefs-Norms (VBN) theory and a newly developed Soil Ethics Survey (SES) instrument for the quantitative component, while using Decision-Making Theory and Social Cognitive Theory to qualitatively explore how farmers’ experiences and reflections shape their soil ethics. Quantitative findings revealed …

Ex Vivo Evaluation Of Polyethylene Cable Compared To Stainless Steel Cerclage Wire In A Canine Fracture Model, Seila Natasha Day

Theses and Dissertations

A long oblique osteotomy model was created using paired canine cadaveric femurs. The osteotomies were stabilized with either three ultra-high molecular weight polyethylene (UHMWPE) cables (n=10) or three 18 gauge stainless steel loop cerclage wires (n=10). Cyclic testing was performed in four-point bending by applying increasing force at 2 Hz until construct failure, defined as ≥2mm of actuator displacement. Data analyzed included cycles to failure, load at failure, and dynamic stiffness. There was no statistically significant difference in any of the outcomes tested between constructs. Visible loosening was noted in all loop cerclage constructs. No visible loosening of the UHMWPE …

Mapping Renewable Energy Opportunities: Increasing Rural Energy Resilience In Mississippi Through Extension And National Program Insights, Kaitlyn Brooke Gordon

Theses and Dissertations

There has been an increased interest in renewable energy opportunities in Mississippi in recent years but limited educational material on this topic and a lack of knowledge among residents on various renewable energy options. Therefore, the main objectives of this study were to 1) conduct a comprehensive review of renewable energy educational resources and 2) increase knowledge of renewable energy in youth through the development of a new statewide Extension program. The environmental scan resulted in 45 usable responses from 117 potential participants, and programmatic details were received for 54 Extension programs or other forms of educational material. Evaluation results …

Strategic Use Of Exogenous Feed Enzymes And Sodium Bisulfate To Optimize Broiler Production, Spencer Thomas Karn

Theses and Dissertations

Poultry producers must continually evaluate nutritional strategies to enhance broiler performance and sustainability. Chapter II assessed sodium bisulfate (SB) applied to litter, feed, and water across a 42-day grow-out. Applying SB to litter reduced pH, while 0.3% and 0.4% dietary SB improved feed conversion ratio (FCR). Water acidification with SB during the final week did not impair performance, supporting its use as a preharvest intervention. Chapter III evaluated phytase at 500, 1500, and 2000 FTU/kg, with or without protease, in reduced amino acid diets over 56 days. Birds fed a nutrient-adequate diet with 1500 FTU/kg phytase outperformed all reduced-amino acid …

From Gametes To Genes: Genetic Quality Assessment Of Anuran Cryopreserved Spermatozoa And Derived Embryos, Trinity Isabella Kassuhn

Theses and Dissertations

Sperm cryopreservation is an important tool within the suite of assisted reproductive technologies (ART) as it enables long-term storage of genetically valuable gametes. However, knowledge of the diagnostic criteria for assessing sperm quality and the genetic consequences of using cryopreserved sperm in amphibians is limited. This gap has raised concerns in captive breeding and reintroduction programs regarding the potential impact that cryopreserved sperm and the derived embryos may have on a population. The thesis aims to investigate how sperm cryopreservation affects the genetic material in both sperm and resulting embryos, with implications for in situ and ex situ amphibian populations. …

Documenting Children’S Use, Physical Activity, And Social Play In Tom Lee Park’S Playscape, Laurel Kelton

Theses and Dissertations

The benefits of nature and physical activity on children’s health and development are well documented. However, many children lack access to nature and physical activity. Researchers have found that “innovative playgrounds” —which, by definition, are more likely to include natural elements that facilitate nature immersion— are associated with increased physical activity and duration of stay. This thesis is a case study of a public innovative playground at Tom Lee Park. It sought to understand the playground’s areas and physical characteristics that have higher levels of use, physical activity, and social play and longer durations of stay. Data was collected over …

Understanding Pollinator-Forb Interactions And Evaluating Trapping Methods For Pollinator Monitoring In Lawns Of The Southeastern United States, Sara Rose Kirby

Theses and Dissertations

Urban turfgrass landscapes are widespread across the southeastern United States but offer limited ecological value under conventional management. This thesis evaluates the pollinator support potential of ten forb species commonly found in low-maintenance lawns and assesses the effectiveness of two insect sampling methods, sweep netting and pan trapping. Over two years of field surveys, native forbs such as Symphyotrichum divaricatum and Claytonia virginica supported significantly greater insect abundance and diversity than introduced species. Network and modularity analyses revealed that native plants facilitated more specialized pollinator interactions, including those involving oligolectic bee species. In a complementary study, pan traps effectively sampled …

Impact Of Buffered Dry Vinegar And Fermented Onion Juice On The Quality And Shelf-Life Of Fresh Pork Breakfast Sausage, Emily M. Little

Theses and Dissertations

The demand for clean-label meat products has increased interest in natural alternatives to synthetic antioxidants and antimicrobials. This study evaluated the effects of buffered dry vinegar (BDV), fermented onion juice (FOJ), and their combination (CMB) on microbial stability and sensory quality of pork sausage during 9 days of refrigerated storage. Sausages were assigned to control, FOJ (0.5%), BDV (0.5%), or CMB (0.25% each) treatments. BDV and CMB significantly reduced aerobic and psychrotrophic counts by days 7-9, while yeast increased across all treatments over time, reaching ~7 Log CFU/g by day 9. Sensory analysis revealed lower oxidation and off-note intensity in …

Finite Element Modeling Of Plasma Membrane Injury From Mechanical Stress: A Combined Finite Element And Machine Learning Approach, Eric Flynn Mabowitz

Theses and Dissertations

Low back pain is a leading cause of disability across a wide range of occupations and environments. Exposure to whole-body vibration (WBV) has been linked to an increased prevalence of low back pain, as well as certain neurophysiological complications. While current understanding of WBV effects is largely based on tissue- and whole-body-level studies, a significant gap remains in knowledge regarding how vibrational forces propagate through individual cells. This knowledge gap limits a comprehensive understanding of how these forces affect the human body at the microscopic level. To address this, the present study employs both two-dimensional (2D) and three-dimensional (3D) finite …

Synthetic Mrna Induced Tf1.17-Specific Antibody Response Against Tritrichomonas Foetus For Preputial Delivery In Bulls, Kenzie Mcatee

Theses and Dissertations

Bovine trichomoniasis, caused by Tritrichomonas foetus, remains a persistent reproductive disease in cattle due to asymptomatic carriage in bulls and lack of effective treatments. This thesis evaluated the use of synthetic mRNA to drive expression of TF1.17- specific antibodies, targeting a conserved surface adhesin essential for parasite colonization. Membrane-anchored and secreted IgG1 constructs were transfected into bovine kidney cells, resulting in time-dependent antibody expression verified via NanoLuc luminescence. In vivo, aerosolized mRNA administration to bull calves led to localized antibody expression in preputial secretions. Although immunofluorescence assays detected fluorescence signal, high background limited interpretation of specific binding to T. foetus. …

Evaluating The Dietary Supplementation Of Soy Lecithin For Channel Catfish (Ictalurus Punctatus), Crystal Lodi Conde

Theses and Dissertations

Soy lecithin (SL), a phospholipid rich ingredient derived from soybeans, was tested to evaluate the effects on channel catfish growth and physiological responses. In Trial 1, formulated diets with gradual SL levels were tested. Fish fed 1.5% SL had improved feed efficiency, while 0.5% SL enhanced protein conversion efficiency. The SL influenced cortisol levels during recovery from air exposure stress and improved survival after bacterial challenge. The Trial 2 tested three different lipid sources: Soybean oil (SBO; control), 1% SL + SBO, and catfish oil (CFO). The SL-fed fish also presented improved feed efficiency compared to the SBO group. There …

Native Bee Communities Within Restored Montane Longleaf Pine Ecosystems, Mary Mcteague

Theses and Dissertations

Montane longleaf pine ecosystems are remarkably biodiverse and highly understudied. Like other longleaf pine ecosystems, montane longleaf pine forests have faced declines. These ecosystems have been undergoing restoration efforts to reestablish floral understories. Flourishing pollinator communities are essential to successful restoration efforts. This study seeks to understand the influence of site history and characteristics on native bee communities in restored montane longleaf pine ecosystems, and to establish a methodology for creating pollination networks in these ecosystems by using DNA metabarcoding to analyze bee-collected pollen. Our results showed that community composition varied based on month and site history. Site history impacted …

Investigation Of Guayule Resin As An Oil-Based Wood Treatment, Jordan Miller

Theses and Dissertations

Development of alternative treatments for wood product protection is an ongoing focus throughout the wood products industries. All manufacturers hope to increase the use life of their products, while ensuring that their products do not have a harmful impact on their surrounding environment. One way of approaching this is to source potential components from other agricultural sources. Guayule resin is produced as a by-product of rubber extraction from the guayule plant (Parthenium argentatum). The resin has been reported to have insecticidal and microbial properties, but there are numerous problems with utilization, including how to extract it and apply it due …

Evaluating The Impacts Of Cover Crops At Different Nitrogen Rates On Soil Microbial Dynamics Within A Sweetpotato Production System, Lahari Nekkalapudi

Theses and Dissertations

A field study was conducted from 2023 to 2024 at Pontotoc, Mississippi, to evaluate the effects of cover crops and nitrogen (N) fertilizer on soil microbial communities in sweet potato production. The study followed a randomized split-block design with three cover crops (Clover, Wheat, and Fallow) and three N rates (0, 50, and 100 lb N acre⁻¹), each replicated four times. Soil samples were collected at cover crop termination, sweet potato planting, and harvest. Bacterial and fungal communities were analyzed using Illumina HiSeq sequencing. Soil properties such as total carbon, total nitrogen, pH, POXC, and microbial activity (AWCD) were also …

Augmenting Healthcare Communication: Context-Aware Ai Frameworks For Clinical Decision Support And Automated Summarization, Subash Neupane

Theses and Dissertations

Healthcare communication is plagued by fragmented medical knowledge, patient misunderstanding of care plans, and clinician burnout from documentation burdens. These inefficiencies cost the U.S. healthcare system over $300 billion annually due to preventable nonadherence and administrative waste [47, 19]. While Artificial Intelligence (AI) technology like Large Language Models (LLMs) offer potential solutions, existing systems fail to deliver personalized, context-aware guidance or automate documentation without sacrificing accuracy. This dissertation addresses these gaps through three novel context-aware AI frameworks such as MedInsight, ClinicSum, and ClinicDuo. MedInsight leverages a multi-source context augmentation approach to synthesize patient centric medical responses by integrating Electronic Health …

An Evaluation Of The Mississippi 4-H/Ffa Replacement Beef Heifer Development Contest, Lindsey V. Pansano

Theses and Dissertations

The Mississippi 4-H/FFA Replacement Beef Heifer Development Contest began in 2008 to provide youth with a contest to showcase their managerial skills relating to beef cattle. This study examined the impact of contest participation on development of life skills, technical skills, and choice of occupation. Youth and parents/guardians reported slight to moderate improvement in life skills. The same groups also agreed that technical skills were improved through contest participation. While most youth did not consider the contest to impact their choice of occupation, all indicated that they are currently involved in the beef cattle industry as adults. Overall, these results …

Developing Site Index Curves And Exploring Growth Efficiency Variation In Longleaf Pine Planted On Marginal Agricultural Land In Georgia, Usa, Jabryan Pegues

Theses and Dissertations

With the relative success of the Conservation Reserve Program (CRP), there is a considerable amount of longleaf pine (Pinus palustris Mill.) trees planted on marginal agricultural land, with little to no guides for productivity management. This study was conducted in four distinct age classes of longleaf pine plantations at The Jones Center at Ichauway in Southwest Georgia, USA. Most of these stands were commercially thinned in 2014 and some were impacted by Hurricane Michael in 2018. I developed site index equations to represent growth trajectories of these stands while incorporating growth starting from ground level. Additionally, the concept of tree-level …

Feed-Based Strategies To Improve Poultry Production Efficiency, Anna Kathryn Riggs

Theses and Dissertations

The poultry industry continues to make significant strides in efficiency and innovation, particularly through advancements in nutrition. This thesis explores two key areas within broiler nutrition that are essential to supporting sustainable, cost-effective poultry production. First, the potential of a next-generation exogenous carbohydrase enzyme blend containing beta-mannanase and endo-glucanase is investigated when supplemented into reduced-energy, all-vegetable diets based on corn, soybean meal, and corn distillers dried grains with solubles in male broilers over a 42-day grow-out period, including processing (Chapter II). Second, the thesis examines the use of modeling strategies such as cubic, quadratic, kernel and smoothing spline to predict …

Microbiomics Of Amazonian Fishes And Associations With Human Pathogens (Mycobacterium Ulcerans), Matthew Edwin Scott

Theses and Dissertations

The Amazon Rainforest and Guiana Shield are recognized as two of the most biodiverse ecosystems on Earth, particularly when considering macroorganisms. Relatively little attention has been paid to the microbiological diversity within rainforest ecosystems, or to the interactions among macro- and microbiological communities. To this end, I characterized the effects of habitat and host phylogenic parameters on the gut microbiome of freshwater fishes along the coast and within the Approuague River watershed in French Guiana. The results indicate a river continuum effect on the microbial composition of fishes, as well as a similar continuum pattern along the coast of French …