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Isolation And Culture Of Epichloё For Reinfection Of Endophyte-Free Southeastern Wildrye (Elymus Glabriflorus), Bryna Joann Haile

Theses and Dissertations

Mutualistic relationships between endophytic fungi and grasses have shown to improve the hardiness of the host. This relationship is common in grasses, including North American native grasses that are important in both forage and grassland ecosystems. Elymus species, such as Canada wildrye (CWR), commonly host the endophytic fungi, Epichloё, while southeastern wildrye (SEWR) may not. In this study, seed of CWR and seed and leaves from local SEWR were assessed for endophyte infection. Infection status was confirmed via histological analysis of seed squashes and leaf peels. Presence/absence of endophyte was determined by scanning for mycelia within seed and between leaf …

Adherence To A Gluten-Free Diet And Depression, And Nutrient Distribution In Participants With Celiac Disease, Mohammad K. Shushari

Theses and Dissertations

Celiac disease (CD), an autoimmune disorder affecting millions of Americans, poses significant obstacles leading to a normal life. With no known cure, adherence to a strict glutenfree diet (GFD) is essential. However, the cost and limited availability of gluten-free alternatives can burden individuals with CD. Additionally, factors such as socioeconomic status, nutrient deficiencies, and the nature of the disease may contribute to mental health issues. This study aimed to investigate the influence of adherence to a GFD on depression in CD patients. The prevalence of depression among individuals with CD from diverse backgrounds was examined, along with the analysis of …

Soil Health As Influenced By The Integration Of Cover Crops And Poultry Litter In North-Central Mississippi, Nikitha Reddy Kovvuri

Theses and Dissertations

Soil health-based agricultural management practices are widely promoted to improve soil structure, infiltration and reduce erosion. This study was conducted at two locations in North-Central Mississippi to evaluate the influence of different cover crop species and poultry litter on soil health that can impact crop production, climate change, and resilience. The results indicated that the cover crops showed a little effect on some soil health indicators compared to control treatment. However, in one location, rye, and a mixture of cover crops decreased bulk density and increased available water content and organic matter. The poultry litter had a positive effect on …

Metabolic Adaptation Of Staphylococcus Aureus Pathogenesis And Therapeutic Approach In Diabetic Foot Ulcers., Carol L. Baker

Theses and Dissertations

37.3 million Americans (11.2% of the US population) currently have Type 2 diabetes mellitus (T2DM) with over 1.5 million new cases being diagnosed each year. The multifactorial etiology of the patient having neuropathy, overweight/obesity, foot deformities, ischemia, and infection leads to a condition called diabetic foot ulcer (DFU). One in six patients with a DFU will require amputation with infected DFUs have a 155-fold increased risk of amputation. Staphylococcus aureus is the most common bacteria isolated from severe DFU infections that require amputation. Interestingly, diabetics are more heavily colonized with S. aureus compared to non-diabetics suggesting a unique advantageous adaptation …

Nutritional Strategies To Reduce Salmonella Enteritidis Infections In Laying Hens: Prebiotic, Probiotic, And Precision Biotics, Ishab Poudel

Theses and Dissertations

Salmonella Enteritidis (SE) infections in laying hens is a significant cause of foodborne illness linked to the consumption of contaminated eggs. This dissertation encompasses novel strategies aimed to explore appropriate in-vitro and in-vivo models to evaluate the effects of these novel strategies to reduce SE in laying hens. Firstly, we investigated the potential probiotics, prebiotics, and essential oil combinations to reduce SE in-vitro. The results showed that probiotics and prebiotics are equally effective to reduce SE. In subsequent studies, we evaluated the role of vaccination history on cecal microbiota and SE infections with various doses of oral SE challenge. …

Effectiveness Of Intervention Studies Based On Diet And/Or Physical Activity In Treatment, Prevention, And Management Of Diabetes Among South Asians: A Systematic Review, Ishaan Arora

Theses and Dissertations

The purpose of this study was to describe diet and/or physical activity-based interventions and their control in cardiometabolic risk factors of diabetes for the South Asian (SA) population. A systematic review was conducted in accordance with the PRISMA guidelines. Seventeen randomized control trials meeting the inclusion criteria were included for analysis. Interventions with type-2 diabetic SA showed significant improvements in HbA1c% (4/5 studies), fasting blood glucose (3/4 studies), and postprandial glucose (2/2 studies). Interventions with at-risk/prediabetic and non-diabetic SA showed a modest change in overall outcomes, with significant change reported for post-prandial insulin (3/4 studies), BMI and weight (2/4 studies), …

Assessing The Effectiveness Of Agricultural Extension Advice On Household Food Consumption And Food Security Outcomes In Malawi, Mphatso Chinsinga

Theses and Dissertations

My study examined the influence of agricultural extension advice on household food consumption and food security outcomes in Malawi. I utilized a pooled cross-sectional dataset from the Malawi Integrated Household Survey (IHS) and Integrated Household Panel Survey (IHPS) conducted in 2010, 2013, 2016, and 2019. To identify the effects, multivariate linear and logistic regression models were employed, considering various factors and incorporating fixed effects for survey wave, district, and data collection month. My findings revealed heterogeneity in the impacts of agricultural extension advice on food consumption and food security outcomes. Specifically, the results showed a positive correlation between agricultural extension …

Advancing Poultry Nutrition Through Statistical Strategies To Reduce Experimental Variation And Novel Protease Enzyme Research, Caleb Morgan Marshall

Theses and Dissertations

Increasingly, nutritionists are challenged to optimize broiler genetic capacity, while considering varying ingredient qualities and pricing, to meet production goals and profitability. Due to scale and cost, university and private research is often used by nutritionists to help make these decisions; thus, requiring these facilities to detect small, incremental improvements. In Chapters 1 and 2, processing data from several nutrition research trials were utilized to evaluate the impact of processing personnel, sample size, and unit of analysis on the detection of dietary differences. By accounting for potential variability between personnel (as a covariant) and selecting an adequate sample size for …

Identification And Characterization Of Silk Gland Specific Ugt34 Gene In Helicoverpa Zea, Courtney Nicole Wynn

Theses and Dissertations

Uridine diphosphate glycosyltransferase (UGT) is a multigene family of enzymes responsible for catalyzing glycosylation of small hydrophobic molecules. Recently, a genomic analysis of the corn earworm (Helicoverpa zea) identified 45 different UGT genes. We discovered a UGT gene (UGT34) showing high levels of expression exclusively in the silk gland tissue. The expression levels of UGT34 were analyzed in different developmental stages and silk gland sub-segments, revealing that UGT34 is generally expressed at all larval instar stages and largely expressed in the middle and posterior subsegments of the silk glands. The soybean looper (Chrysodeixis includens), another noctuid …

Effects Of Fire Seasonality On Bachman’S Sparrows In The Longleaf Pine Forests Of Southern Mississippi, Michael D. Warren

Theses and Dissertations

The Bachman’s sparrow (Peucaea aestivalis) is a ground-dwelling, pine-obligate species experiencing range-wide population declines due to land development and fire exclusion. We explored the effects of fire seasonality on wintering Bachman’s sparrow abundance in Southern Mississippi from 2021-2022. We used generalized linear mixed models to investigate differences in sparrow abundance and vegetation characteristics following dormant and growing season fire. We explored the effects of growing season fire on breeding territory vegetation characteristics. Our results indicate that burn type (dormant vs. growing season), native grass groundcover, and shrubs over 1m were the most significant predictors for wintering Bachman’s sparrow …

Impact Of A Feeding Strategy And Management Practices On The Health And Welfare Of Pullets And Laying Hens, Gerald Rodney Self

Theses and Dissertations

The overall purpose of this thesis is to understand the impact of management on commercial egg layers, whether that be environmental-related, health-related, or other possible stressors within the pullet and post-peak phases. Furthermore, the study seeks to examine what effects to performance and production these impacts may induce within a commercial layer in differing phases, specifically the pullet and post-peak phases. Chapter two explores into coccidiosis within the pullet phase, which induced by a commercial vaccine, can provide stress to a pullet, lowering protection against infection, and seriously compromising its growth and development into peak lay. Chapter three explores into …

Survival, Persistence, Regrowth And Morphotype Variation Of Listeria Monocytogenes Strains After Exposure To First Generation And Second Generation Quaternary Ammonium Compounds In Water, Stephen Schade

Theses and Dissertations

Listeria monocytogenes is one of the toughest challenges the food industry is facing today. While quaternary ammonium compounds (QAC) are typically applied at very high concentrations to kill L. monocytogenes, there are some factors that can cause its reduced efficacy in the food processing environment. Sublethal concentrations of stagnated QAC have been found both in processing plants and in waste waters released to the environment. Therefore, the purpose of this study was to investigate the ability of two L. monocytogenes strains, Bug600 (serotype 1/2a) and ScottA (serotype 4b) to persist in lethal and sublethal concentrations of first generation QAC (benzalkonium …

Designing Bioinspired Materials With Tunable Structures And Properties From Natural And Synthetic Polymers, Anandavalli Varadarajan

Theses and Dissertations

Biological systems are composed of complex materials which are responsible for performing various functions, such as providing structural support, mobility, functional adaptation to the environment, damage repair, and self-healing. These complex materials display excellent mechanical properties and can rapidly adapt to external stimuli. Thus, nature inspires in terms of source materials, functions, and designs to develop new-generation structural and functional materials. Polymers (natural or synthetic) are excellent sources of developing materials to mimic the functions of soft segments in biological systems. This dissertation focuses on synthesizing and characterizing two different materials with tunable structures and properties: complexes from natural polysaccharides …

Vaccination And Immune Response Of Channel Catfish (Ictalurus Punctatus) Against Virulent Aeromonas Hydrophila, Basant Mahmoud Ali Gomaa

Theses and Dissertations

Virulent Aeromonas hydrophila (vAh) is a causative agent of motile Aeromonas septicemia (MAS) in catfish. There are limitations in the current therapeutic and preventative strategies against vAh. The pathogenesis of MAS as well as the immune response of catfish to vAh infection are poorly understood. The aim of this study is to: 1) develop a dual live attenuated vaccine against MAS and enteric septicemia of catfish caused by Edwardsiella ictaluri; and 2) evaluate the vAh bacterial load and gene expression patterns in catfish tissues following vAh infection. Previously, six recombinant vAh …

Investigating Specialty Crop Farmers’ Preferences For Contract Design And Attitudes Towards Blockchain-Based Smart Contracts, Esther Mmenaa Agyemang-Duah

Theses and Dissertations

This study examines small and medium scale specialty crop growers’ preferences for marketing contract attributes and willingness to adopt blockchain-based smart contracts. The data used were collected using an online survey and discrete choice experiment. Findings indicate that farmers prefer higher average prices, cash, check or electronic bank payment over cryptocurrency, and immediate payment upon product delivery over delayed payment. When choosing a contract, farmers viewed traditional text-based contracts and digital platforms with automated smart contracts equivalently, on average. On average, farmers showed no preference for providing and not providing traceability lot codes to buyers, and between choosing a contract …

Regional Economic Impacts Of Enterococcus-Related Beach Closures In Mississippi, Jessica Lynn Browne

Theses and Dissertations

High levels of Enterococcus are the most frequent reason for beach closures on the Mississippi Gulf Coast and can be made worse by human activities. When beaches close, tourism can decrease, affecting sales. This study aims to 1) analyze the regional economic impact of beach closures at the county level, 2) show empirically how serious the impact of high levels of Enterococcus are compared to other causes of beach closures, and 3) discuss the policy implications for regional economies linked to beach closures. I use a response function approach with beach closure and county-level monthly gross taxable sales data. Results …

A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans

Theses and Dissertations

Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an …

Use Of Comparative Genomics And In Vitro Screening Approach To Identify Vaccine Candidates For The Food-Borne Pathogen Campylobacter Jejuni, Sabin Poudel

Theses and Dissertations

Campylobacteriosis is a leading foodborne illness worldwide, primarily caused by Campylobacter jejuni (C. jejuni) which is associated with poultry consumption. The emergence of antibiotic resistance has emphasized the need for alternative strategies to control C. jejuni colonization in poultry. To assess the prevalence of C. jejuni in poultry, 270 cloacal swab samples were collected from broilers raised under No-Antibiotics Ever system. Among these samples, 16.3% were identified as C. jejuni positive. Notably, these isolates exhibited a diverse range of virulence factors and antimicrobial resistance genes, with 61.36% of isolates showing hyper-motile and 20.45% demonstrating multidrug resistance. Following isolation, whole genome …

An Analysis Of Coastal Restoration Projects In Alabama And Mississippi, Barbara Nyarkoa Okai

Theses and Dissertations

This study aims to review thirteen coastal restoration projects considering the various ecosystem services provided by restoration and estimates the economic value of one of the ecosystem services of restoration. These ecosystem services include water quality improvement, fish and benthic species productivity, shoreline stabilization, oyster abundance, and marsh growth. The projects represent a set of large-scale projects within Alabama and Mississippi, with construction and monitoring costs ranging from $2.3 million to $50 million per project. To determine the economic value of one of the ecosystem services of coastal restoration projects, I used the meta-analysis method to estimate the willingness to …

The Response Of Bats And Their Insect Prey To Different Coastal Upland Habitat Management Techniques, Amanda Nicole Sartain

Theses and Dissertations

Declining bat populations necessitates a need to understand how different land management techniques influence bat activity. This study assessed the influences of different coastal upland habitat management techniques, such as mulching, prescribed fire, and select cut, on forest bat activity within the Grand Bay National Wildlife Refuge and National Estuarine Research Reserve. Acoustic recorders were used to monitor bat activity and insect and vegetation surveys were used to assess influences on bat activity across different land management techniques. Results demonstrate that overall bat activity was similar across different land management techniques, however larger species adapted for open-space flying were shown …

Is A Test The Best?, Giulia Ronnette Mcdonald

Theses and Dissertations

The test effect (Roediger & Karpicke, 2006) demonstrates that performance on a final test is better when an immediate test is taken after reading a passage rather than rereading. Although transfer appropriate processing has been suggested as a theoretical explanation, the results could be due to elaborative retrieval processes during the immediate test that are not available during restudy. We compared testing to three other strategies using elaborative retrieval—Generating Questions, Read-Recite-Review, Teaching—to determine whether they would be as beneficial as testing. Results showed that each of the alternative strategies produced final test performance equal to that of testing, suggesting not …

Loaded Lipid Emulsified Volatile Anesthetics In Canine Primary Hepatocytes, Patricia De Carvalho Ibrahim Obeid

Theses and Dissertations

In the 19th century, halothane hepatitis became a sensitive and well-known subject in human anesthesiology due to the production of a noxious metabolite further discovered, trifluoroacetic acid. Subsequently, isoflurane, enflurane, and desflurane were also investigated for potentially causing hepatitis through the same metabolite. Sevoflurane, however, does not generate trifluoroacetic acid and is quickly conjugated and excreted.

For more than four decades these anesthetics have been experimentally developed for intravenous injection by having added either a lipid or fluorocarbon-based carrier to produce general anesthesia with less drug and faster onset of action. The use of intravenous emulsified halogenated anesthetics as an …

Multi-Objective Design Optimization Of Two Configurations Of Ventricular Shunts For Hydrocephalus, Will Kirkpatrick

Theses and Dissertations

Hydrocephalus is developed when the flow of cerebrospinal fluid is obstructed in the ventricles and a pressure build-up is generated within the brain. Ventricular shunts are used to remove excess fluid from the brain, but these shunts have a common problem of failure due to the shunt being obstructed by the build-up of astrocytes. To address this, two sets of 27 designs of ventricular shunts were identified and analyzed with parameters that could potentially reduce obstruction risks. The performance of these designs was examined using fluid simulations on these two sets of 27 designs. One set explored close-tipped shunt designs, …

Comparison Of Aging Techniques In Wild Bottlenose Dolphins (Tursiops Truncatus) Of Unknown Age From The Mississippi Sound., Christa Elizabeth Barrett

Theses and Dissertations

Age determination of bottlenose dolphins (Tursiops truncatus) is a critical tool in understanding their health. There are many methods of aging dolphins including morphometrics, counting growth layer groups (GLGs) of teeth, comparing dentin to pulp cavity ratio on dental radiographs, analysis of the pectoral flipper radiographs, and epigenetic testing. The most common method for aging toothed cetaceans is the counting of GLGs in the teeth. Since there are many challenges associated with aging dolphins based on the counting of GLGs, a processing technique that results in better resolution of GLGs is needed. This is a two-part study that …

Effect Of Environmental And Geometrical Factors On Microstructure, Desiccation Cracking, And Carbon Dioxide Flux In Clays, Charles Clayton Goodman

Theses and Dissertations

Studying the effects of extreme conditions, such as high temperatures and low humidity, on soil properties is important to various disciplines, including geotechnical engineering, soil science, waste management, crop management, and ceramics. The goal of this research is to investigate the effect of environmental and geometrical factors on microstructure, desiccation cracking, and CO₂ flux in clays. The objectives of this research are threefold. (1) Understand the effects of temperature on the microstructure of clay soils; (2) develop a standardized procedure for studying desiccation cracking in a laboratory setting with reliable and repeatable results; and (3) develop an environmental chamber …

A Survey Analysis Of Southeastern U.S. Dairy Producers’ Emotional States And Their Subjective Pain Perception Of Dairy Cows, Michelle M. Schuh

Theses and Dissertations

Dairy producers play a central role in evaluating and seeking treatment or care for animal pain. The primary aim of this study is to examine dairy producers’ emotional states and professional quality of life and analyze the relationship between these variables and their perception of pain in dairy cattle. Dairy farm owners and managers of 65 southeastern U.S. herds participated in a survey that included demographic information, the Depression, Anxiety, and Stress Scale, a modified Professional Quality of Life Scale, and 23 items requiring participants to evaluate various painful conditions in cattle.

Object Itineraries Of Metal Artifacts From The Stark Farm Site Complex (22ok778), Madeleine Marie Hale

Theses and Dissertations

This thesis focuses on creating a deeper understanding of European-made metal objects uncovered at a Late Mississippian period site by using an object itinerary theoretical framework. This theory allows for objects to be understood and analyzed without bias as it acknowledges Indigenous and archaeological perspectives by considering the many different contexts an object moves through. I apply this theory to these European-made metal objects that were transformed and used by the Chicasa as a way to introduce a more collaborative and holistic approach to the other analytical methods being used at Stark Farm (22OK778). This process was completed by using …

Upland Cotton And Nematodes: An Analysis Of Historical Resistance, Upcoming Threats, And Co-Inoculation Effects, Amanda Gaudin

Theses and Dissertations

Upland cotton (Gossypium hirsutum ) is an important fiber crop grown throughout the southern United States. Plant-pathogenic nematodes are worm-like animals that feed on the roots of most agronomic crops, including cotton. The southern root-knot nematode (Meloidogyne incognita, RKN) and the reniform nematode (Rotylenchulus reniformis, RN) cause significant yield losses in cotton every year. Current sources of resistance are effective but limited, therefore historical screenings of cotton accessions were revisited in search for novel resistance sources. None were identified but many of the screened accessions possessed markers of known root-knot nematode and reniform nematode resistance. …

Non-Destructive Evaluation Of White Striping And Microbial Spoilage Of Broiler Breast Meat Using Structured-Illumination Reflectance Imaging, Ebenezer O. Olaniyi

Theses and Dissertations

Manual inspection is a prevailing practice for quality assessment of poultry meat, but it is labor-intensive, tedious, and subjective. This thesis aims to assess the efficacy of an emerging structured illumination reflectance imaging (SIRI) technique with machine learning approaches for assessing WS and microbial spoilage in broiler breast meat. Broiler breast meat samples were imaged by an in house-assembled SIRI platform under sinusoidal illumination. In first experiment, handcrafted texture features were extracted from direct component (DC, corresponding to conventional uniform illumination) and amplitude component (AC, unique to the use of sinusoidal illumination) images retrieved from raw SIRI pattern images build …

Evaluating The Role Of The Bovine Vaginal Microbiome In Neonatal And Maternal Health Outcomes, Riley D. Messman

Theses and Dissertations

The dam vaginal microbiota is the first major microbial inoculating community within the neonate. The composition of the dam vaginal microbiota has implications in calf commensal microbiota development. Alterations of the dam microbial community prior to parturition could alter inoculating communities and immune responses in both the dam and calf. Thus, authors aimed to elucidate the microbial community composition of the bovine dam vaginal and calf nasal microbiota post-partum after utilizing betadine lavages (BL). The dam vaginal and calf nasal microbial communities and immune responses were evaluated at 0-, 15-, 30- and 60-day post-partum. Microbiota composition of the dam haircoat, …