Life Sciences Commons^™

Psychological Determinants Of Physical Activity And The Prediction Of Physical Activity Levels In African American Men, Alvin L. Morton Iii

Doctoral Dissertations

African American (AA) men experience disproportionally higher rates of non-communicable, chronic diseases (e.g., cardiovascular, type 2 diabetes, and renal failure) than White men. Physical activity (PA) is known to reduce the progression of CVD, type 2 diabetes, and renal failure. National statistics illustrate that AA men are less likely to get sufficient levels of PA to obtain health benefits. Although many factors (e.g., biomedical, socio-cultural) influence participation in PA, the psychological factors at the individual level are essential to beginning and maintaining activity. Therefore, understanding the psychological determinants of PA in AA men and their associations with meeting national guidelines …

Characterization And Management Of Auxin-Resistant Palmer Amaranth In Tennessee, Delaney C. Foster

Doctoral Dissertations

Palmer amaranth has a long history of evolving resistance to herbicides to the point it has become a significant row crop production obstacle. Cotton and soybean growers were offered new technologies in 2016, expanding in-crop herbicide options to include dicamba or 2,4-D. Within three years of commercialization, dicamba use in these crops increased ten-fold and growers began to report Palmer amaranth escapes in west Tennessee auxin-tolerant production systems. A survey of Palmer amaranth escapes in dicamba and 2,4-D-tolerant cotton and soybean fields in Tennessee was conducted in the fall of 2021 with the objective of determining if poor control was …

Leveraging Mass Spectrometry-Based Proteomics And Post-Translational Modifications For System-Wide Understanding Of Bioenergy Plants And Their Environment, Him K. Shrestha

Doctoral Dissertations

Bioenergy research focuses on utilizing renewable biomass feedstocks to produce biofuels and bioproducts to address growing concerns about energy security and climate change. To better understand the details of bioenergy crop production and conversion to bioproducts, it is essential to characterize bioenergy plants and their environments at a molecular systems level. Mass spectrometry has emerged as a promising technique for detailed proteomic information, including post-translational modifications (PTMs), of molecular processes and cellular functions of biological systems. In this dissertation, proteomic approaches have been optimized and implemented to deepen our understanding of the interaction of plants and their environment in a …

Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan

Doctoral Dissertations

Understanding the shape variation of the human sphenoidal sinus is important to several areas of research. This includes clinical investigation (sinus pathology and safe endoscopic endonasal surgical practice) and paranasal sinus evolution (for which there is still no consensus). Yet, the sphenoidal sinus has high morphological variation, prohibiting its quantification through traditional geometric morphometric landmarking methods. The sphenoid body, and thus also the sinus contained within, is located directly at the developmental center of the basicranium in humans, where the three cranial fossae meet at the midline, and adjacent to the three synchondroses which are the sites of cranial base …

Microwave Frequency Control Algorithms For Use In A Solid-State System To Achieve Improved Heating Performance, Ran Yang

Doctoral Dissertations

Microwave is a popular food heating technique. Its unique volumetric heating principle enables fast heating while also leads to nonuniform heat distribution, where the standing wave patterns caused by the magnetron as microwave source is the main reason for the poor uniformity. Solid-state microwave generator is a promising solution to address the nonuniform heating, as it allows flexible microwaves, with frequencies in a range rather than fixed, and thereby, the varied thermal patterns by different frequencies could overcome the standing wave pattern issue. Previous studies on the frequency control strategy mainly focused on orderly shifting frequencies in range, while not …

Predicting Immunization Status At Arrival In Tennessee Stocker Calves, Claire E. Hunkler

Masters Theses

Bovine respiratory disease is a multifaceted disease with agent, host, and environmental factors. Stocker calves are at high risk of contracting the disease through many stressors like weaning, transportation, commingling, etc. The purpose of this project was to test if externally observed physical characteristics of calves on arrival at a stocker facility can be used to predict calfhood vaccination status determined based on antibody titer levels. Knowledge of highly correlated characteristics could allow stocker operators to reduce the occurrence of BRD through targeted management strategies, thus lowering morbidity, mortality, and treatment costs. Ear notches, blood, and visual characteristics were collected …

Encapsulation Of Antimicrobial Peptides In Bicontinuous Microemulsions For Topical Delivery To Surgical Site Infections And Chronic Wounds, Madison A. Oehler

Masters Theses

Surgical site infections and chronic wounds, especially those caused by antibiotic-resistant microorganisms, result in hospitalization and fatalities each year. Methods to prevent these infections, such as cleaning and preparing medical tools, have had minimal success in preventing infections. Further, antibiotic treatments have become less successful in treating infections and wounds because of antibiotic-resistant bacteria. Antimicrobial peptides (AMP) are a possible treatment solution for wound infections. AMPs are oligopeptides that occur in nature or can be synthesized in vitro which possess a broad spectrum of antimicrobial activity against bacteria and other harmful microorganisms. AMPs operate by disrupting the packing arrangements of …

A Novel Transmembrane Ligand Inhibits T Cell Receptor Activation, Yujie Ye

Doctoral Dissertations

T lymphocytes (T cells) play essential roles in the adaptive immune system. Each mature T cell expresses one type of functional T cell receptor (TCR). The TCR recognizes antigens bound to the major histocompatibility complex (MHC) in antigen presenting cells. The resulting stimulation signal crosses the transmembrane domain of TCR and initiates downstream signaling cascades. The human immune system relies on TCRs to recognize a variety of pathogens. Normally, TCR can distinguish the self-antigens from pathogenic antigens. However, dysfunction or aberrant expression of TCRs causes different inflammatory and autoimmune diseases, which afflict millions of people annually (Chapter I). Current treatments …

Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman

Doctoral Dissertations

Host-associated microbes live in dangerous environments as a result of host immune killing, nutrient provisioning, and physiological conditions. Bacteria have evolved a host of surface and secreted proteins to help interact with this host environment and overcome nutrient limitation. The studies included within this dissertation describe the identification of a novel bacterial secretion system which has evolved to transport these symbiosis mediating proteins. This system, termed the type eleven secretion system (T11SS), is present throughout the Gram negative phylum Proteobacteria, including many human pathogens such as Neisseria meningitidis, Acinetobacter baumanii, Haemophilus haemolyticus, and Proteus vulgaris. Furthermore, …

Water Availability As A Cross-Scale Driver Of Microbial Functions And Free Viral Abundance In Soil, Aubrey K. Fine

Doctoral Dissertations

Viral infection is widespread in natural microbial communities, with extensive study in aquatic ecosystems demonstrating direct influence on host physiology, functional activity, and mortality. While similar dynamics are assumed to occur across ecosystems, soils are distinct microbial habitats where soil physiochemical structure and water availability constrain resource availability. These unique environmental conditions have been widely demonstrated to affect microbial distribution, diversity, and functional activity in bulk soil, while their influence on virus-microbe interactions and free viral abundance remains limited. To address this knowledge gap, this research had three broad aims: i) to investigate variability in microbial responses to drying-rewetting cycles …

Rumen Biogeographical Regions And Their Impact On Microbial And Metabolome Variation, Macey P. Soltis

Masters Theses

The rumen microbiome is a complex microbial network critical to the health and nutrition of its host, due to their inherent ability to convert low-quality feedstuffs into energy. In rumen microbiome studies, the ventral sac is sampled from due to ease of access and repeatability. However, anatomical musculature demarcates the rumen into five sacs which may support distinct microbial communities. The distinction among the microbes may generate functional variation among the rumen microbiome, thus, specialized tasks within different sacs. The objective of this study was to determine the rumen liquid metabolome and epimural, planktonic, and fiber-adherent bacterial communities among each …

Systematic Evaluation Of Database Builds In Metaproteomics For The Advancement Of Microbiome Research, Katherine E. Ostrouchov

Masters Theses

The microscopic life that inhabits a human shares a unique bond with its host. Microbes perform many functions that are vital to the survival of the human species and have long been shown to regulate the absorption of nutrients and to promote immune function. A lack of exposure to certain microbes early in life, excessive antibiotic usage, and improper diet can perturb human microbiomes and lead to disease. Since the emergence of omic sequencing technologies, it has now become possible to measure and monitor the genes and proteins made by these microorganisms to better understand how they contribute to host …

Staphylococcal Surface Proteins As Vaccine Candidates For The Control Of Staphylococcal Mastitis In Dairy Cows, Jessica Jean Vidlund

Masters Theses

Bovine mastitis, an inflammation of the mammary gland, is the single most costly disease of dairy cattle. Staphylococci, a major bacteria that cause bovine mastitis, are commonly divided into two major groups: Staphylococcus aureus and non-aureus staphylococci (NAS), previously known as coagulase-negative Staphylococcus species (CNS). Current mastitis control programs are not fully effective against staphylococcal mastitis and antibiotics are not sustainable due to limited success and the emergence of antimicrobial resistant bacteria. Non-antibiotic sustainable control tools, such as effective vaccines, are critically needed. Our lab developed and evaluated Staphylococcus aureus surface associated protein (SASP) and Staphylococcus chromogenes surface associated protein …

Functional Analysis Of Soybean Proteinase Inhibitor Genes And Cyst Nematode-Inducible Synthetic Promoters For Insects And Nematode-Resistance In Plants, Mst Shamira Sultana

Doctoral Dissertations

Proteinase inhibitors (PIs) from legumes have the potential for use as protectants in response to pests and pathogens. Soybean (Glycine max) contains two trypsin inhibitors (TIs): Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI). In this study, the possible role of soybean TIs in plant defense against insects and nematodes was investigated. In addition to the three known TIs (KTI1, KTI2 and KTI3), novel inhibitors KTI5, KTI7, and BBI5 were identified in soybean. Their functional role was further examined by overexpression in soybean and Arabidopsis. In vitro enzyme inhibitory assays showed significant increase in trypsin and chymotrypsin inhibitory …

Accurate Simulation Of Reads And Improved Strategies For Abundance Estimation Supporting Reduced Representation Sequencing For Metagenomics, Ryan Kuster

Doctoral Dissertations

Next generation sequencing has impacted all areas of biology by providing affordable investigations into some of the most complex processes underpinning life. With its ubiquitous application, there is still benefit in considering the nuances of the technology and its downstream analysis. Sequencing libraries produced by fragmenting DNA with restriction enzyme digests limit the scope of sequencing to a reduced set of genomic loci, allowing for deeper sequencing of those regions at a reduced cost per sample. These sequencing libraries have been used to determine genetic markers within populations of closely related individuals due to their sensitivity and preservation within populations. …

“Sometimes The People Giving The Care Get A Little Overlooked”: Athletic Trainers’ Personal Use Of Psychosocial Strategies And Interactions With Mental Performance Consultants, Alexander Bianco

Doctoral Dissertations

In National Collegiate Athletic Association Division I (NCAA DI) athletic departments, athletic trainers (ATs) must navigate an array of stressors in the workplace, and are effectively performers themselves (Estock & Simon, 2018, Mazerolle et al., 2013). While ample research has been conducted on the stressors that ATs experience (see Oglesby et al., 2020) there has been limited work surrounding how ATs can best navigate this environment. Therefore, the purpose of the current investigation was to explore NCAA DI ATs’ perceptions of and experiences with the personal use of psychosocial strategies and sport psychology services to manage their stress, improve their …

What I Talk About When I Talk About Integration Of Single-Cell Data, Yang Xu

Doctoral Dissertations

Over the past decade, single-cell technologies evolved from profiling hundreds of cells to millions of cells, and emerged from a single modality of data to cover multiple views at single-cell resolution, including genome, epigenome, transcriptome, and so on. With advance of these single-cell technologies, the booming of multimodal single-cell data creates a valuable resource for us to understand cellular heterogeneity and molecular mechanism at a comprehensive level. However, the large-scale multimodal single-cell data also presents a huge computational challenge for insightful integrative analysis. Here, I will lay out problems in data integration that single-cell research community is interested in and …

An Investigation Of Intrinsic And Extrinsic Factors That Influence Soil Microbial Succession During Human Decomposition, Allison R. Mason

Doctoral Dissertations

Decomposer organisms play a vital role in terrestrial nutrient cycling, breaking down complex organic compounds and providing nutrients for primary producers. Microbial communities and other decomposers associated with a vertebrate carcass, or the “necrobiome”, are critical for degradation and recycling of soft tissues following vertebrate mortality. The impact of microbial decomposers in vertebrate decomposition has been shown with regard to soil microbial communities, where the presence of soil microbes impact decomposition rate and undergo succession. However, current assessments of microbial ecology within decomposition-impacted soils have primarily focused on one aspect of microbial succession: succession of bacterial taxa for forensic applications. …

The Influence Of Traits On Species Responses To Climate Change: Does Warming Negatively Impact Native Species More Than Invasive Species?, Margaret Anne Mamantov

Doctoral Dissertations

Current climate change is increasing global temperatures so that many organisms are now experiencing temperatures outside of their thermal tolerance, which threatens their survival. Organisms respond to physiologically stressful temperatures to reduce this threat. Organisms respond to warming through three main mechanisms: range shifts, adjustments via phenotypic plasticity, and evolutionary adaptation. Organisms vary in their ability to utilize these three mechanisms, leading to differences in the magnitude and success of their adjustments to temperature change. Here, I examine how organismal traits influence variation in species response to climate change. Chapter one addresses how physiological tolerance may influence the rate of …

Corn (Zea Mays L.) Production In Living Mulch Systems, Grazing Potential, And Economic Viability, Marcia Peireira Quinby

Doctoral Dissertations

Living mulch (LM) is a practice in which forages are grown simultaneously with the main crop, serving as a living cover throughout the growing season. The LM systems were developed to alleviate concerns of soil depletion and finding ways to reduce tillage negative effects on soil productivity. In addition, when legumes are use can decrease the reliance on N fertilizer. The use of corn in LM have been previously studied due to the crop being a large commodity in the U.S.; In addition, the ability to graze the LM after corn production can increase the land use efficiency. To determine …

Better Understanding Genomic Architecture With The Use Of Applied Statistics And Explainable Artificial Intelligence, Jonathon C. Romero

Doctoral Dissertations

With the continuous improvements in biological data collection, new techniques are needed to better understand the complex relationships in genomic and other biological data sets. Explainable Artificial Intelligence (X-AI) techniques like Iterative Random Forest (iRF) excel at finding interactions within data, such as genomic epistasis. Here, the introduction of new methods to mine for these complex interactions is shown in a variety of scenarios. The application of iRF as a method for Genomic Wide Epistasis Studies shows that the method is robust in finding interacting sets of features in synthetic data, without requiring the exponentially increasing computation time of many …

Population Genetics Of Populus Trichocarpa For Targeted Breeding As A Biofuel Crop, Cai John

Doctoral Dissertations

Populus trichocarpa (poplar) is a woody species native to the western U.S. and Canada. As a fast-growing crop, it has been under investigation by the Department of Energy as a resource for liquid biofuel production. Having recently expanded the collection of poplar whole-genome sequences so that it spans the entire natural species range, we have the novel opportunity to study adaptive responses across this range. This work starts with an initial proof of concept study in a well-studied portion of the species range that has complete whole-genome sequences and RNA expression. The completeness of these data allow robust validation of …

Genome Evolution In The Salicaceae: Genetic Novelty, Horizontal Gene Transfer, And Comparative Genomics, Timothy Yates

Doctoral Dissertations

Genome evolution is a powerful force which shapes genomes over time through processes like mutation, horizontal transfer, and sexual reproduction. Although questions which aim to explore genome evolution are broad, they are all understood through the discovery and comparison of genetic variation. For example, genetic diversity may explain differences in phenotypes, etiology of disease, and is essential for phylogenomic analysis. Recently, the democratization of next generation and third generation DNA sequencing technologies have allowed for genomics to produce large amounts of sequence data. This has facilitated the capture of genetic variation at species and population scales.

Populus and Salix are …

Switching Palmitoyl And Oleoyl Positions In Sn-2 And Sn-3 Of A Triacylglycerol Led To Differential Body Weight Gain Rates And Hepatic Gene Expressions In Mice Fed A High-Fat Diet, Xinge Hu

Masters Theses

Alterations of triacylglycerol (TAG) are associated with metabolic diseases such as obesity and diabetes. The fatty acyl groups in a TAG molecule determine its characteristics from melting temperature to digestion and absorption. We hypothesize that the TAG fatty acyl position affects the body weight (BW) gain and lipid metabolism in mice fed a high-fat diet (HFD, 36 % w/w diet). Six-week-old male C57BL/6J mice were randomly assigned to 3 dietary groups, 1,2-dipalmitoyl-3-oleoylglycerol (PPO), 1,3-dipalmitoyl-2-oleoylglycerol (POP), and chow control. The food intake and BW were measured daily during 6 weeks of treatment. The PPO group had significantly higher food intake, caloric …

Optimal Stocker Production Strategies For Spring And Fall Calving Cow Herds, Cora Beth Key

Masters Theses

This thesis consists of two chapters discussing the economics of raising stocker beef cattle in the southeast United States. The objective of the first chapter is to estimate supplemental feed cost for spring-calving cows, spring-born stockers, cows calving in the fall, and fall-born stockers, while considering the seasonality of forage production and nutritional needs. The chapter explores ways producers can lower their feed costs and demonstrates the importance of managing hay expenses for cattle producers to control cost. The objective of chapter two is to determine the profit-maximizing stocker period in an integrated cow-calf and stocker operation with both fall- …

Efficacy Of Sequential Estrus Synchronization And Timed Artificial Insemination In Beef Cattle Beginning 19 Days After An Initial Timed Artificial Insemination, Courtnie Carter Bridges

Masters Theses

A breeding program utilizing single fixed-timed artificial insemination (AI) was compared to a resynchronization program for a second fixed-timed AI. Angus and Angus cross primiparous and multiparous cows were randomly assigned to one of two treatment regimens; either single TAI (CON; n=468) or two sequential TAI (RS; n=473). The main objectives were assessing pregnancy rates and analyzing fetal age to estimate calving distribution rates between the two treatment groups. The 7-day CO-synch + CIDR protocol was utilized in both treatment groups to synchronize estrus for TAI-1 at 60h - 66h post- Prostaglandin injection (PGf2α). Animals in the RS treatment groups …

Computational Analysis Of Transcriptional And Post-Transcriptional Feedback Loops In Development And Cell Differentiation, Benjamin Rigel Nordick

Masters Theses

Regulation of gene expression is critical to organism development and health. Positive and negative feedback in networks of gene regulatory interactions are associated with the maintenance of distinct cell states/types or oscillations, respectively. Recent computational studies identified two structures of positive feedback relevant to establishment of cell type: interconnected transcriptional “high-feedback” loops and a purely post-transcriptional feedback loop arising from multiple microRNA molecules cooperatively regulating one mRNA. The goals of this work were to develop methods for analyzing often-unintuitive high-feedback loops in large networks, generalize the two new regulatory structures to consider oscillation, and further explore the ability of post-transcriptional …

A Rapid And Ultra-Sensitive Biosensing Platform Based On Tunable Dielectrophoresis For Robust Poc Applications, Yu Jiang

Doctoral Dissertations

With the ongoing pandemic, there have been increasing concerns recently regarding major public health issues such as abuse of organophosphorus compounds, pathogenic bacterial infections, and biosecurity in agricultural production. Biosensors have long been considered a kernel technology for next-generation diagnostic solutions to improve food safety and public health. Significant amounts of effort have been devoted to inventing novel sensing mechanisms, modifying their designs, improving their performance, and extending their application scopes. However, the reliability and selectivity of most biosensors still have much to be desired, which holds back the development and commercialization of biosensors, especially for on-site and point-of-care (POC) …

Efficient Network Domination For Life Science Applications, Stephen K. Grady

Doctoral Dissertations

With the ever-increasing size of data available to researchers, traditional methods of analysis often cannot scale to match problems being studied. Often only a subset of variables may be utilized or studied further, motivating the need of techniques that can prioritize variable selection. This dissertation describes the development and application of graph theoretic techniques, particularly the notion of domination, for this purpose. In the first part of this dissertation, algorithms for vertex prioritization in the field of network controllability are studied. Here, the number of solutions to which a vertex belongs is used to classify said vertex and determine its …

Enterobactin-Based Immune Interventions Against Gram-Negative Bacterial Infections, Huiwen Wang

Doctoral Dissertations

Enterobactin (Ent)-mediated iron acquisition is critical for many Gram-negative bacteria to survive in the host. Given the bacteriostatic effect of lipocalin-2 resulting from its potent Ent-binding ability, immune interventions directly targeting Ent is a promising antimicrobial strategy against Gram-negative bacterial infections. Moreover, hyperimmune egg yolk antibody is an emerging passive immune agent for the control of bacterial infections. Oral administration of anti-Ent egg yolk antibody may confer passive immune protection against Ent-dependent enteric pathogens. In this dissertation study, multidisciplinary approaches in conjunction with different model systems (in vitro, in vivo, and ex vivo) were used to …