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The Impact Of Simulated Microgravity On The Growth Of The Model Legume Plant Medicago Truncatula, Gemma Elizabeth Lionheart Jan 2017

The Impact Of Simulated Microgravity On The Growth Of The Model Legume Plant Medicago Truncatula, Gemma Elizabeth Lionheart

Electronic Theses and Dissertations

Simulated microgravity has been a useful tool to help understand plant development in altered gravity conditions. Thirty-one genotypes of the legume plant Medicago truncatula were grown in either simulated microgravity on a rotating clinostat, or a static, vertical environment. Twenty morphological features were measured and compared between these two gravity treatments. Within-species genotypic variation was a significant predictor of the phenotypic response to gravity treatment in 100% of the measured morphological and growth features. In addition, there was a genotype–environment interaction (G×E) for 45% of the response variables, including shoot relative growth rate (p < 0.0005), median number of roots (p ∼ 0.02), and root dry mass (p < 0.005). These findings are discussed in the context of improving future studies in plants space biology by controlling for genotypic differences, and by connecting traits to their underlying genetic causes by using genome-wide association (GWA) mapping. In the long-term, manipulation of genotype effects, in combination with M. truncatula’s symbiotic relationships with rhizobacteria and arbuscular mycorrhizal fungi, will be important for optimizing legumes for cultivation on long-term space missions.


Risk, Reward, And The Role Of Habitat Selection On Community Dynamics In Temporary Ponds, Matthew Robert Pintar Jan 2017

Risk, Reward, And The Role Of Habitat Selection On Community Dynamics In Temporary Ponds, Matthew Robert Pintar

Electronic Theses and Dissertations

The processes that generate patterns of species diversity within and among habitat patches are a fundamental topic of interest in ecology. Traditionally, there was a focus on post-colonization effects such as predation, however, pre-colonization processes, such as habitat selection, are equally important determinants of community structure. In freshwater systems, the lethal effects of dominant predators (particularly fish) are well established, while the transition from permanent to temporary ponds is a defining characteristic. This transition produces distinct communities characterized by organisms with complex life cycles and plastic developmental strategies. This means that many organisms occupying habitat patches arrive there by the …


Towards A Better Understanding Of Secondary Metabolite Production In Toxic Marine Algae, Thuy My Nguyen Jan 2017

Towards A Better Understanding Of Secondary Metabolite Production In Toxic Marine Algae, Thuy My Nguyen

Electronic Theses and Dissertations

Roseofilum reptotaenium is a marine cyanobacteria responsible for the loss of 50% of corals worldwide due to Black Band Disease (BBD). Investigating the basis for secondary metabolite production by R. reptotaenium cultures revealed a suite of potent anti-malarial and anticancer compounds that likely include dolastatin 10 and monomethyl auristatin D (MMAD). These R. reptotaenium cultures are non-axenic (not pure monocultures) and R. reptotaenium appears to require the presence of several heterotrophic bacteria to survive. Scanning Election Microscope (SEM) images show closely associated bacteria. Preliminary metagenomic analysis indicates three dominant non-cyanobacterial phyla: Bacteroidetes, Planctomycetes, and Proteobacteri (?-proteobacteria accounted for >50% of …


An Evaluation Of The Mississippi Recipes For Success Resource From The Perspective Of Child Nutrition Directors, Chelsea L. Bell Jan 2017

An Evaluation Of The Mississippi Recipes For Success Resource From The Perspective Of Child Nutrition Directors, Chelsea L. Bell

Electronic Theses and Dissertations

The Mississippi Recipes for Success (MRS), A Guide for Child Nutrition Programs provides printed and online resources for child nutrition directors. These resources include recipes and methods to assist directors in effectively implementing United States Department of Agriculture (USDA) nutrition standards. The purpose of this study was to investigate if child nutrition directors utilize these resources, as well as assess child nutrition directors’ perceptions of the helpfulness, satisfaction, and importance of the various components of the online and 2014 printed versions of the MRS. Data collection for this study involved an online survey that evaluated directors’ usage of the resources …


Diet Quality And Food Insecurity Among University Students: The Role Of Food Preparation Ability, Katharine Halfacre Jan 2017

Diet Quality And Food Insecurity Among University Students: The Role Of Food Preparation Ability, Katharine Halfacre

Electronic Theses and Dissertations

No abstract provided.


Effect Of Body Image Awareness Program On Weight Satisfaction In Ncaa Division I Female Athletes, Derionne Brooks Jan 2017

Effect Of Body Image Awareness Program On Weight Satisfaction In Ncaa Division I Female Athletes, Derionne Brooks

Electronic Theses and Dissertations

No abstract provided.


Contribution Of Specific Amino Acids To Calcium-Dependent Dimerization Of Epithelial Cadherin, Xiaoyun Z. Howard Jan 2017

Contribution Of Specific Amino Acids To Calcium-Dependent Dimerization Of Epithelial Cadherin, Xiaoyun Z. Howard

Electronic Theses and Dissertations

Cadherins are calcium-dependent molecules that play essential roles in embryonic development, tissue morphogenesis, and cancer progression. Epithelial (E-) cadherin is present at adherens junctions, structures that are important for maintaining tissue integrity. At adherens junctions, cell–cell adhesion complexes are formed as clusters of cadherin dimers through strand-swapped dimerization between two interacting protomers from adherent cells. Recently, a number of studies of dimer formation of E-cadherin supported a two-step adhesive binding model. First, an inter-molecular initial encounter complex (X-dimer) forms at the linker region of the first two extracellular domains, EC1 and EC2. Next, strand-swap dimerization occurs via exchange or ''swap'' …


The Effect Of Road Crossings On Stream-Associated Salamanders Within Holly Springs National Forest, Caleb Ashton Aldridge Jan 2017

The Effect Of Road Crossings On Stream-Associated Salamanders Within Holly Springs National Forest, Caleb Ashton Aldridge

Electronic Theses and Dissertations

Road crossings have significant effects on wildlife, but there is limited information on how road crossings affect stream-associated salamanders. Stream-associated salamanders are vital to their ecological communities and are likely to experience the effect of roads more readily than other species due to their physiological characteristics. To test the effects of road crossings on stream-associated salamanders, I surveyed 12 pairs of confluent streams – one stream crossed by a road and the other not in each pair – within Holly Springs National Forest, Mississippi. Surveys in the summer of 2015 were used to measure abundance and species richness of stream-associated …


Nucleic Acid Clamp-Mediated Transcriptional And Translational Modulation Of Oncogenes Via The Stabilization Of G-Quadruplexes, Taisen Hao Jan 2017

Nucleic Acid Clamp-Mediated Transcriptional And Translational Modulation Of Oncogenes Via The Stabilization Of G-Quadruplexes, Taisen Hao

Electronic Theses and Dissertations

G-quadruplexes (G4s) are non-canonical secondary nucleic acid structures that exit in various biologically important regions within a cell, such as the promoters of DNA, 5’-Untranslated regions (UTR) of mRNA and telomeres. These secondary structures tend to cluster around 1 kb from transcriptional start sites across all human chromosomes in addition to at telomeric regions. Extensive efforts from many research groups have been dedicated to targeting G4s in oncogenic promoters, telomeres, and 5’-UTRs with traditional small molecules. However, most small molecules recognizing multiple G4s raising potential issues in terms of utilizing these small molecules clinically. Therefore, we developed a novel nucleic …


Biochemical And Molecular Assessment Of Toxicity Of Primaquine Metabolites On Erythrocytes, Jagrati Jain Jan 2017

Biochemical And Molecular Assessment Of Toxicity Of Primaquine Metabolites On Erythrocytes, Jagrati Jain

Electronic Theses and Dissertations

The 8-aminoquinoline (8AQ) antimalarial drug primaquine (PQ) is the only drug for prevention of malaria relapse. Moreover, PQ also has gametocytocidal activity against Plasmodium falciparum. However, clinical use of PQ has been limited due to its hemolytic toxicity, especially in glucose-6-phosphate dehydrogenase deficient (G6PDd) individuals. Phenolic and quinone metabolites generated via cytochrome P450-dependent pathways appear to be responsible for hemolytic effects of PQ. However, the mechanism for the hemolytic toxicity of PQ is still poorly understood. To explore the mechanism, targets, and pathways for toxicity of PQ, normal and G6PDd human erythrocytes were treated with the potential hemotoxic metabolites of …


Conditions Responsible For The Success Of Carnivorous Plants In Nutrient-Poor Wetlands, Matthew John Abbott Jan 2017

Conditions Responsible For The Success Of Carnivorous Plants In Nutrient-Poor Wetlands, Matthew John Abbott

Electronic Theses and Dissertations

Despite the vast array of past research focused on carnivorous plants, few studies have investigated the ecological interactions between carnivorous and non-carnivorous plant species. I addressed the following three questions: (1) does niche complementarity promote coexistence between fire-adapted carnivorous and non-carnivorous species? (2) do carnivorous plants rely on both leaf traps and arbuscular mycorrhizal fungi to access different nutrients that are in high demand after fire in nutrient poor bogs? (3) why are carnivorous plants largely absent from nutrient-rich wetlands? I addressed the first question by examining the three-way interacting effects of fire, prey-derived nutrient availability, and root competition from …


Responses Of The Ocellated Turkey (Meleagris Ocellata) To Human Disturbance, Thomas Hughes Martin Jan 2017

Responses Of The Ocellated Turkey (Meleagris Ocellata) To Human Disturbance, Thomas Hughes Martin

Electronic Theses and Dissertations

Habitat loss and habitat degradation are major drivers of the current biodiversity crisis. Nowhere else are these threats more severe than in the tropics. Because the tropics are estimated to contain as much as 60% of all the species on Earth, they are critically important for the conservation of biodiversity. To conserve species we need to understand both the factors that lead to extinction and how the taxa that persist are able to adapt to the rapid anthropogenic change of their environment. The Ocellated Turkey (Meleagris ocellata) is a Neotropical galliform bird of conservation concern because it faces a rapidly …


Regulation Of The Kras Promoter In Pancreatic Cancer By Proteins And Small Molecules, Harshul Batra Jan 2017

Regulation Of The Kras Promoter In Pancreatic Cancer By Proteins And Small Molecules, Harshul Batra

Electronic Theses and Dissertations

DNA-binding proteins play a pivotal role in cell biology. The major class of DNA-binding proteins are transcription factors (TFs). TFs are central to almost every fundamental cellular process such as cell development, differentiation, cell growth, and gene expression. They account for 10% of the genes in eukaryotes. In mammals, more than 700 TFs are identified to be DNA-binding TFs. They bind to the TF binding sites (TFBSs) in the genome and regulate the expression of their target genes. kRAS is a proto-oncogene with intrinsic GTPase activity, that contributes to cell proliferation, division, and apoptosis. kRAS mutations are observed in >95% …


Characterizing The Developmental And Reproductive Toxicities Of Cannabidiol And Δ9-Tetrahydrocannabinol, Dennis Ray Carty Jan 2017

Characterizing The Developmental And Reproductive Toxicities Of Cannabidiol And Δ9-Tetrahydrocannabinol, Dennis Ray Carty

Electronic Theses and Dissertations

Medical marijuana is legal in twenty-nine of the United States and an additional nineteen states have passed legislation for cannabidiol (CBD) treatment of drug-resistant epilepsy, such as Dravet Syndrome (DS) which is diagnosed in children as young as two months. While CBD has shown anecdotal and recently clinical trial efficacy in reducing seizure frequency in DS patients, little is known about the potential adverse side-effects on child physiology, brain development, adult disease, or subsequent generations. Moreover, CBD is rarely administered without including low concentrations of Δ9-tetrahydrocannabinol (THC). The goal of this project is to characterize the relative morphological, behavioral, reproductive, …


A Kinematic Comparison Of Shoulder And Elbow Dynamics Influenced By The Shoe-Surface Interface In Youth And Adolescent Baseball Pitchers, Jacob Richard Gdovin Jan 2017

A Kinematic Comparison Of Shoulder And Elbow Dynamics Influenced By The Shoe-Surface Interface In Youth And Adolescent Baseball Pitchers, Jacob Richard Gdovin

Electronic Theses and Dissertations

From 1994-2006, 1.5 million baseball injuries were treated within emergency departments across the United States while the upper extremity was the second most commonly injured body part. Although it has been determined that pitch count, pitch type and pitching mechanics are the main contributors to upper extremity pain in baseball pitchers, footwear has not been considered a potential factor. Therefore, the purpose of this study was to determine how baseball-specific footwear [turf shoes (ts) and molded cleats (mc)] affects the shoulder and elbow dynamics of youth and adolescent pitchers during an overhead pitch on various surface inclinations [flat ground (fg) …


Historical Refuges And Recolonization Routes In The Southern Appalachian Mountains, Inferred Through Phylogeographic Analysis Of The Spotted Wintergreen (Chimaphila Maculata), John Daniel Banusiewicz Jan 2017

Historical Refuges And Recolonization Routes In The Southern Appalachian Mountains, Inferred Through Phylogeographic Analysis Of The Spotted Wintergreen (Chimaphila Maculata), John Daniel Banusiewicz

Electronic Theses and Dissertations

Phylogeography has recently benefited from incorporation of coalescent modeling to test competing scenarios of population history of a species. Ecological niche modeling has also been useful in inferring areas of likely suitable habitat during past climate conditions. Several studies have examined the population history of biota in the Southern Appalachian Mountains and how they responded to climate change associated with the end of the Last Glacial Maximum (~18,000 years ago), though few studies have focused on understory plants. This study redressed that knowledge gap thorough examination of the phylogeographic history of the understory plant Chimaphila maculata, which is native to …


The Reptile Gut Microbiome: Its Role In Host Evolution And Community Assembly, Timothy Colston Colston Jan 2017

The Reptile Gut Microbiome: Its Role In Host Evolution And Community Assembly, Timothy Colston Colston

Electronic Theses and Dissertations

I characterize the endogenous (gut) microbiome of Squamate reptiles, with a particular focus on the suborder Serpentes, and investigate the influence of the microbiome on host evolution and community assembly using samples I collected across three continents in the New and Old World. I developed novel methods for sampling the microbiomes of reptiles and summarized the current literature on non-mammalian gut microbiomes. In addition to establishing a standardized method of collecting and characterizing reptile microbiomes I made novel contributions to the future direction of the burgeoning field of host-associated microbiome research. Through persistent and rigorous fieldwork I amassed the largest …


Food Insecurity And Eating Behaviors Of Collegiate Male Athletes, Kacie Poll Jan 2017

Food Insecurity And Eating Behaviors Of Collegiate Male Athletes, Kacie Poll

Electronic Theses and Dissertations

PURPOSE: To assess the relationship of high school (HS) and collegiate (OM) household food security status (FSS) to current food consumption behaviors in a sample of NCAA Division 1 male, collegiate athletes ≥18 years of age (y). METHODS: A cross-sectional survey of NCAA athletes from a Southeastern Conference (SEC) university was approved by the Institutional Review Board and conducted during August-September, 2016. The questionnaire included the USDA food security survey module and questions related to disordered eating behaviors and food hoarding USDA methods were used to calculate FSS. RESULTS: Participating athletes (n=111) were 19.7±1.4 y and primarily white, football players …


Relationships Between Dietary Habits, Demographics, And Hike Outcome Among 2015 Pacific Crest Trail Backpackers, Lauren Ann Black Jan 2017

Relationships Between Dietary Habits, Demographics, And Hike Outcome Among 2015 Pacific Crest Trail Backpackers, Lauren Ann Black

Electronic Theses and Dissertations

This quantitative research study explores the relationship between dietary patterns, hiker demographics, and total miles hiked during a backpacking trip on the Pacific Crest Trail (PCT). Long hiking distances, low rate of thru-hike completion, consumption of processed and ready to eat foods, weight loss, and large time and monetary strains are comthemes accepted anecdotally by the backpacking population11. However, these themes have yet to be adequately researched and validated for long distance backpackers and PCT backpackers specifically. The online survey gathered data from 151 backpackers who hiked the PCT in 2015. Significant positive correlational relationships were found between the number …


Impact Of Hydration On Collegiate Athletic Performance, Fatigue, And Recovery, Lauren Woodard Jan 2017

Impact Of Hydration On Collegiate Athletic Performance, Fatigue, And Recovery, Lauren Woodard

Electronic Theses and Dissertations

The impact of dehydration on several key physiological functions that are critical for athletic performance is well studied. Hydration monitoring has been known to have significant value on impaired physical functions by maximizing performance during training and competition. Impaired physical functions has been suggested as a limitation on explosive strength, musculoskeletal output, cardiovascular output, and proper technique in contact sports. The purpose of this study was to investigate the relationship between hydration levels and physiological profiles that can be used as a proactive approach in monitoring a collegiate athlete’s athletic performance, fatigue, and recovery status. It was hypothesized that insufficient …


Evidence Of Chemical Camouflage In Pirate Perch (Aphredoderus Sayanus); Avoiding Detection By Colonizing/Ovipositing Prey Through Chemical Crypsis, Tyler Breech Jan 2017

Evidence Of Chemical Camouflage In Pirate Perch (Aphredoderus Sayanus); Avoiding Detection By Colonizing/Ovipositing Prey Through Chemical Crypsis, Tyler Breech

Electronic Theses and Dissertations

No abstract provided.


Evaluation Of Nutrition Education In The Families In Transformation (Fit) Program., Sydney Anne Devers Jan 2017

Evaluation Of Nutrition Education In The Families In Transformation (Fit) Program., Sydney Anne Devers

Electronic Theses and Dissertations

No abstract provided.


Nickel Reduces Calcium Dependent Dimerization In Neural Cadherin, Matthew Paul Dukes Jan 2017

Nickel Reduces Calcium Dependent Dimerization In Neural Cadherin, Matthew Paul Dukes

Electronic Theses and Dissertations

Cadherins are the primary transmembrane component in adherens junctions, structures that link the actin cytoskeleton in adjacent cells within solid tissues including neurological synapses, epithelium and endothelium. Cell-cell adhesion by cadherins requires the binding of calcium ions to specific sites in the extracellular region. Given the complexity of the cell adhesion microenvironment, we are investigating whether other divalent cations might affect calciumdependent dimerization of neural-(N-) cadherin. The first chapter focuses on studies to characterize the impact of binding physiological magnesium (II) or neurotoxic nickel (II) on calcium-dependent N-cadherin function. Physiological levels of magnesium have only a small effect on the …


G-Quadruplexes As Molecular Targets For Transcriptional Control, Rhianna Kyelle Morgan Jan 2017

G-Quadruplexes As Molecular Targets For Transcriptional Control, Rhianna Kyelle Morgan

Electronic Theses and Dissertations

DNA G-quadruplexes (G4s) have gained interest in modern drug discovery efforts. The majority of G4 research, including the mass of this research, heavily focuses on cancer therapeutic development, as G4s are more pronounced in oncogenic promoters compared to the rest of the genome, our efforts extend towards neuroprotection as well. In particular, this work covers G4s in the promoters of MYC, VEGF, kRAS, and Bcl-2. MYC and VEGF harbor the two most well described promoter G4s to date, and their stabilization cultivates transcriptional silencing. Downregulation of MYC reduces cell growth and alters cell energetics; it is promising for a variety …