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Diversification In The Neotropics – Evolution And Population Genetics Of The Armored Catfish Hypancistrus Sp. From The Xingu River, Marcella Goncalves Santos

Electronic Theses and Dissertations

The Xingu River, one of the largest tributaries of the Amazon River, is currently in peril due to the recent construction of hydroelectric dams, but little is known about the numerous fish species it supports. This dissertation focuses on three pleco catfish species belonging to the genus Hypancistrus from the Xingu River with partially overlapping distributions: H. zebra, H. sp. (L174), and H. sp. (L66/333). Chapter 1 is a bibliographic review of Amazonian freshwater fish diversity, with the goal of discussing the hypotheses of speciation mechanisms that can be tested in this system, including the relative importance of ecological adaptation …

Child Nutrition Program Managers’ Evaluation Of The Mississippi Recipes For Success (Mrs) Guide, Alexandra Hallmark

Electronic Theses and Dissertations

Findings from this study can assist MDE-OCN in future updates of the MRS Guide. MRS is an excellent resource for CNP professionals and can be used by other state child nutrition programs as a guide when developing or updating their own menu planning tools and training resources. The Mississippi Department of Education Office of Child Nutrition (MDE OCN) has been assisting child nutrition programs with meeting the nutritional needs of the students since 2000. The Mississippi Recipes for Success (MRS) guide is the latest recipe database developed and updated by MDE-OCN. This guide contains a database that is comprised of …

The Independent And Combined Effects Of Hypoxia And Tributyltin On The Eastern Oyster, Crassostrea Virginica, Ann Fairly Barnett

Electronic Theses and Dissertations

Oysters are vital to the health of estuarine ecosystems and provide critical ecosystem services, such as water quality improvement, nursery habitat for commercially important fisheries, and shoreline stabilization. Despite their ecological and economic importance, oyster reefs are exposed to many stressors, and oyster populations in Mississippi have declined dramatically in recent years. The present study focuses on the effects of hypoxia and tributyltin (TBT) on the Eastern oyster, Crassostrea virginica. Hypoxic events are increasingly comin coastal ecosystems worldwide, and TBT is a legacy toxicant once used as an antifoulant. The effects of these stressors were assessed on adult oysters deployed …

The Evolution Of Coral Snake Mimicry, Renan Janke Bosque

Electronic Theses and Dissertations

Scientists have regarded mimicry as one of the most amazing examples of the power of natural selection. Early observations by naturalists of the mimetic association between venomous New World coral snakes of the genus Micrurus and harmless mimics has stimulated an intense debate about the causes and consequences of mimicry that persists today. Despite its medical, evolutionary and historical importance our understanding of evolution within the genus Micrurus is negligible. My dissertation explores the evolution of mimicry within South American coral snakes and their mimics using a multi-scale framework involving macroevolutionary (Chapter I), geographic/morphological concordance (Chapters II and III), behavioral …

Do Individual Responses To Resistance Exercise Exist To An Extent That Can Be Detected Beyond That Of Measurement Error/Random Biological Variability?, Scott J. Dankel

Electronic Theses and Dissertations

Millions of dollars are spent analyzing inter-individual differences in response to resistance exercise, but the lack of a non-exercise control group means they may simply be examining random error. The purpose of this study was to determine whether there are inter-individual differences in response to two distinct resistance exercise protocols. Participants (n=151) were randomly assigned to one of 3 groups as follows: (1) a traditional exercise group performing 4 sets to failure with a load that could be lifted 8-12 times; (2) a one-repetition maximum (1RM) training group performing a 1RM test each visit; and (3) a non-exercise control group. …

A Sustainable Future In The Implementation Of Clinical Pharmacogenomics, Nicholas Keeling

Electronic Theses and Dissertations

Purpose: The sustainability of clinical pharmacogenomics requires further study of clinical education on the topic, its effects on clinical workflow, and the responsibilities of different providers for its delivery. Tools from the discipline of implementation science were utilized herein to help achieve the purposes of the three studies. The broad purpose of this dissertation is to advance the work of clinical pharmacogenomic implementation through a more rigorous convergence with implementation science.

Methods: Three studies constitute the whole of this dissertation. The first is a scoping review that provides a broad characterization of the methods utilized in available peer-revieliterature focusing on …

Effects Of Impoundments On The Community Assemblage And Gene Flow Of Stream Crayfishes, Zanethia Choice Barnett

Electronic Theses and Dissertations

Dams and their impoundments block movement of stream organism and change stream physiochemical properties, which subsequently changes biological assemblages and creates barriers to gene flow. While changes in species assemblages and gene flow have been assessed for numerous impoundments and stream organisms, no study has assessed the effects of large impoundments on crayfish assemblages and population genetic diversity and connectivity. I examined the physiochemical, biological, and genetic effects of impoundments on crayfishes. Between May 2015 and August 2017, I sampled multiple sites up- and downstream of three impounded streams, and along the lengths of two unimpounded streams, in the Bear …

Evaluation Of Best Practices In Child Nutrition At Child Care Centers In Mississippi, Whitney Clara Black

Electronic Theses and Dissertations

Results: Survey responses indicated that the majority of directors rated themselves as skilled at several key areas of best practices, especially in creating a clean, pleasant place for the children to eat and in using program nutrition requirements to ensure that food and nutrition needs of the children are met. Analysis of the center menus proved the latter to be true as the recommendations for Vitamin A, Vitamin C, calcium, and iron were either met or exceeded for females 4-8 years-old, and males 4-8 years-old. A need for more training was also indicated, especially in writing food and nutrition procedures …

The Effect Of Magnesium Supplementation On Physical Performance Of Collegiate Football Players, Shannon Marie Boguth

Electronic Theses and Dissertations

Mg supplementation can maximize energy stores for exercise, decrease indicators of inflammation, and increase the rate of lactate clearance. While these functions of Mg can benefit exercise capabilities, research is lacking on their effects on specific performance parameters. The purpose of this study was to determine if Mg supplementation would increase performance parameters in NCAA Division-I football players. Eighty-one participants were separated into position groups and randomly assigned to receive a daily placebo, low dose of Mg (100 mg), or high dose of Mg (200 mg). Participants completed a pre- and post-test for performance parameters that included 1RM clean, 1RM …

Continuous Production Of Raloxifene Hydrochloride Loaded Nanostructured Lipid Carriers Using Hot-Melt Extrusion Technology, Derick Muhindo

Electronic Theses and Dissertations

The aim of this study was to utilize a continuous process for the production of Raloxifene Hydrochloride (RX-HCl) loaded NLC formulations for extended drug release using hot-melt extrusion technology coupled with probe sonication, and also to evaluate the in vitro characteristics of the prepared NLCs by particle size, PDI, zeta potential, entrapment efficiency, drug loading, and in vitro drug release profile. Preparation of the NLCs using HME technology involved two main steps, first formation of a pre-emulsion after extrusion and then size reduction of the pre-emulsion using probe sonication to obtain the NLCs. Process parameters for the extrusion process like …

Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy

Electronic Theses and Dissertations

Reproductive interference occurs when the mating behaviors of one species negatively impact the fitness of another species. It is of increasing interest in invasive species biology because the introduction of alien species often leads to novel sexual interactions with native taxa, which can contribute to their decline. I examined whether reproductive interference plays a role in the decline of native green treefrogs (Hyla cinerea) following invasions of Cuban treefrogs (Osteopilus septentrionalis) in the southeastern United States. The impetus for this study revolves around similarities in spectro-temporal features of Cuban treefrog courtship calls and green treefrog aggressive calls. The significance of …

Extended Adolescence: The Ecology And Endocrinology Of Facultative Paedomorphosis, Jason R. Bohenek

Electronic Theses and Dissertations

Phenotypic plasticity is an adaptation to unpredictable environments whereby an organism of a single genotype may express more than one phenotype under differing environmental conditions. Phenotypic plasticity can manifest as polyphenisms, which is an extreme form of phenotypic plasticity that produces two or more discrete, alternative phenotypes. The expression of alternative phenotypes is controlled by biotic and abiotic environmental factors, which variably affect the strength and direction of phenotypic outcomes. Using a model polyphenic salamander, I sought to understand the ecological and hormonal processes that regulate alternative phenotype expression. The mole salamander (Ambystoma talpoideum) and eastern newt ( …

Cultural Influences On Body Size Ideals Among African American Women In The Mississippi Delta, Lois Marie Coleman

Electronic Theses and Dissertations

Results: One-on-one interviews yielded 25 cognitive maps. The maps contained a total of 169 concepts with 294 connections among them. The lowest number of variables identified on a participant’s map was 4 and the highest was 11. The lowest number of connections made on a participant’s map was 4 and the highest was 39. Through qualitative condensing and matrix addition, the 169 concepts were used to create 27 variables with 134 connections. Feedback from focus group participants resulted in the addition of 3 variables and 9 connections.

Healthy Eating Opportunities And Choices For University Faculty, Selby Rebecca Entrekin

Electronic Theses and Dissertations

College food environments can be obesogenic settings due to the availability of fast food restaurants and buffet style cafeteria’s accessible to the university community. These environments often foster eating behaviors that can contribute to rising obesity rates in the United States. The aim of this study was to identify university faculty’s perceptions of the campus food environment and access to healthy foods. Investigated were barriers to making healthy food choices on campus and strategies ion how to provide and encourage better food choices. Questions were developed to identify barriers, perceptions, and solutions to improve the healthy eating environment on campus. …

Pharmacokinetic Study Of Novel Anthraquinone Analogues, Yuhan Guo

Electronic Theses and Dissertations

Small molecules functioning as negative regulators of MDM2 have been considered as promising anti-cancer agents. A series of novel anthraquinone (AQ) analogues upregulate p53, a well-known tumor suppressor, by inactivating its antagonist protein MDM2. The novel AQ compounds synthesized through the modifications on the rhein scaffold were reported to have successfully arrested tumor growth. To have a better understanding of their underlying metabolism in vivo, pharmacokinetic (PK) studies were performed for the AQ compounds. A selective, accurate and reproducible assay methodology for PK study was set up for each AQ compound. The stabilities of AQ compounds were then evaluated …

Food Insecurity And Produce Behaviors Of Adults With Children In Rural, Appalachian Mississippi, Tiffany Shirley

Electronic Theses and Dissertations

Adults living in food insecure households consume fewer fruits and vegetables than adults living in food secure households (Hanson & Connor, 2014). The purpose of this study was to examine differences in fruit and vegetable behaviors (intakes; perceptions) of parents of elementary school children by food security status (food secure compared to food insecure; fully food secure compared to not fully food secure) in rural, Appalachian Mississippi. A cross-sectional survey of parents (n=1144) recruited from three elementary schools in rural, Appalachian Mississippi utilized validated measures of produce behaviors: 1) fruit, vegetable, and total produce intakes; 2) perceived benefits of barriers …

Stabilization Of Dna I-Motif Structures By 7-Aminoactinomycin D, An Anti-Tumor Drug, Justin Lane Parmely

Electronic Theses and Dissertations

Alternative DNA structures are likely to form from Watson-Crick B-form DNA when antitumor drug known to bind DNA loops -- can affect the iM structure. Our results demonstrate as an i-motif (iM). While both structures are known to exist in vivo they are energetically uphill can utilize intercalating cytosine-cytosine base pairing to form a four-stranded structure known controlled by alternative DNA structures like G4s and iMs. especially during processes that involve superhelical duress. A guanosine rich strand can form a facilitate their stabilization. In this report we present data on how 7-aminoactinomycin D -- an formation. Earlier it was believed …

Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess

Electronic Theses and Dissertations

Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect …

The Influence Of Site Connectivity On Zooplankton Assemblage Dynamics Within The Lower Mississippi River Floodplain, Jarrod Sackreiter

Electronic Theses and Dissertations

Zooplankton are important components of the food web of such lotic systems. Although capable of motility, they are weak swimmers and their distribution and community composition across a floodplain is strongly affected by patterns of water flow and hydrologic connectivity. However, there has been little research on the zooplankton dynamics of large rivers, such as the Lower Mississippi River (LMR). From morphological identification of zooplankton across the connectivity gradient, I assessed the degree to which hydrologic connectivity acts as an explanatory factor influencing spatial and temporal variation in zooplankton assemblage structure. Second, I compared the use of morphological identification to …

Developing Zebrafish As An In Vivo Model To Screen Compounds For Anti-Cancer Activity In Human Breast Cancer, Trisha Dhawan

Electronic Theses and Dissertations

Breast Cancer (BC) is the most frequently diagnosed cancer; 1:8 women are at risk of developing BC in her lifetime. Cancer metastasis causes the majority of deaths in BC patients. Moreover, side effects of traditional chemotherapeutic drugs (TCD) impair the quality of life of these patients. Discovery and development of safe and effective new therapies is imperative for the treatment of BC and targeting metastasis. The goal herein is to further expand the applicability of in vivo xenotransplantation of human BC cells in transgenic zebrafish to screen potential chemotherapeutics for toxicity and efficacy. For xenotransplantation, MCF-7, BT-474, and MDA-MB-231 BC …

The Role Of Dunc13 In Ethanol Tolerance, Yusuke Wachi

Electronic Theses and Dissertations

Although the effects of ethanol on presynaptic activity have been studied, the molecular mechanisms and the changes in gene expression which are responsible for inducing ethanol tolerance are unclear. Munc13-1 is an active-zone protein that is essential for presynaptic vesicle fusion. This protein interacts with vesicle fusion machinery at presynaptic active zones in the mammalian brain. The C1 domain of Munc13-1 binds diacylglycerol (DAG), which helps membrane localization of this protein and promotes vesicle fusion, facilitating synaptic vesicle release. Previously, it was shown that ethanol binds to the C1 domain of Munc13-1 in vitro at concentrations below 100 mM (Das …

Variations In The Dragonfly Microbiome Through Life Stages And Its Ability To Harbor Antibiotic Resistant Bacteria, Sarah Russell

Electronic Theses and Dissertations

Juvenile dragonflies (nymphs) may possess the ability to pass their microbiome to the adult life stage through metamorphosis. If this is so, the environment in which the nymph develops may have an effect on the adult microbiome. In this study, the gut microbiomes of 13 species of dragonfly were compared across life stages and when collected from environments at different levels of urbanization. The gut of each dragonfly was removed, DNA extracted, and a portion of the bacterial 16S rRNA gene amplified and sequenced. Gut suspensions were also plated on antibiotic amended plates to determine the potential for dragonflies to …

Analysis Of Brevundimonas Subvibrioides Developmental Signaling Systems Reveals Unexpected Differences Between Phenotypes And C-Di-Gmp Levels, Lauryn Anne Sperling

Electronic Theses and Dissertations

The DivJ-DivK-PleC signaling system of Caulobacter crescentus is a signaling network that regulates polar development and the cell cycle. This system is conserved in closely related bacteria, including the sister genus Brevundimonas. Previous studies had shown unexpected phenotypic differences between the C. crescentus divK mutant and the analogous mutant of Brevundimonas subvibrioides, but further characterization was not performed. Here, phenotypic assays analyzing motility, adhesion, and pilus production (the latter characterized by a newly discovered bacteriophage) revealed that divJ and pleC mutants have mostly similar phenotypes as their C. crescentus homologs, but divK mutants maintain largely opposite phenotypes than …

A Mechanistic Study Of The Teratogenic Potential Of 4-O-Methylhonokiol (Mh) On Japanese Medaka (Oryzias Latipes), Santu Kumar Singha

Electronic Theses and Dissertations

An additional goal of this project was to characterize the Wnt/β-catenin signaling pathway to unravel the adverse potential of MH on the cardiovascular system (CVS). Our study suggested that MH-mediated cardiovascular injury may be caused due to upregulation of some major components of the Wnt/β-catenin pathway through expression of excessive pro-inflammatory mediators. Moreover MH decreased expression of ErbB3 and NRG-2 suggesting impaired cardiac structure. MH exposure caused a slow heartbeat blood occlusion absence of blood circulation decreased hatching efficiency and increased mortality in medaka embryos in a concentration- and time-dependent manner. MH might cause blood vessel occlusion by increasing the …

An Experimental Test Of Controls On Resource Exchange In An Ectomycorrhizal Mutualism, Amber Lynn Horning

Electronic Theses and Dissertations

Models of resource exchange mutualisms utilize economic principles to explain how the costs and benefits of these interactions vary with environmental context. All of these models use a ratio of resource exchange (e.g., nitrogen: carbon) as the central variable, and it is unclear whether such exchange ratios predict outcomes of mutualisms in natural systems. Corrêa et al. (2008) hypothesized instead that the absolute flux of the most limiting nutrient, rather than the ratio of the two exchanged resources, best explains the benefits of resource exchange mutualisms. To distinguish between these two competing hypotheses, we measured resource transfers, and their ratios, …

Environnmental Influences On Caribbean Octocoral-Symbiodiniaceae Symbioses, Mark Mccauley

Electronic Theses and Dissertations

A Caribbean octocoral colony is an assemblage of the octocoral host, dinoflagellate algae (family Symbiodiniaceae), bacteria and other microbes, together functioning as meta-organism (holobiont). Even though octocorals dominate many Caribbean reefs, compared to scleractinian corals, little is known about their biology under ambient or potentially stressful conditions. Of the nine species of octocorals (gorgonian corals, Order: Alcyonacea) studied, each had significantly different polyp behaviors, biochemical compositions, Symbiodiniaceae parameters, isotopic signatures, in addition to hosting distinct microbial assemblages. We identified multiple Symbiodiniaceae species (Breviolum minutum, Breviolum B41, Breviolum B1a and Breviolum B1i), inhabiting the gorgonians. These symbioses were temporally and …

The Impact Of A Fruit And Vegetable Intervention On School Cafeteria Fruit And Vegetable Selection And Consumption In A Rural, Appalachian Mississippi Elementary School, Michelle Weber

Electronic Theses and Dissertations

Fruit and vegetable intake for children in the United States is low, which puts them at risk for poor health in the future. The National School Lunch Program meal pattern and nutrition standards for participating schools include increased fruits and vegetables, compared to previous standards. Using a pretest-posttest design, this study examined the effect of a fruit and vegetable intervention on fruit and vegetable food selection and consumption in a rural, Appalachian Mississippi elementary school. A six-week intervention (nutrition education, cafeteria tastings, fruit and vegetables for home usage/backpack program) was implemented. The unannounced fruit and vegetable selection and waste measurements …

Implementing Mass Spectrometry For The Structural And Compositional Analysis Of Proteins, Mohammad Riaz

Electronic Theses and Dissertations

Lectins are sugar-binding proteins that perform various biological functions such as cellular recognition attachments etc. Pulses the dried edible seeds of certain plants are great sources of lectins and a proteomics approach directed at lectins identification would bring substantial improvement in the lectin identification process. Lectins from nine different plant species were analyzed through SDS-PAGE and proteomics analysis. After LC-MS/MS analysis proteins were identified with protein database searches using Uniprot. Functionally uncharacterized proteins were identified with database searches were annotated with the Pfam and NCBI-CCD databases. In-vitro pharmacological screening will be carried out to assess the pharmacological effects of these …

Safety Assessment And Chemical Fingerprint Analysis Of Medicinal Plants Commonly Consumed As Herbal Teas; Rooibos (Aspalathus Linearis) And Moringa (Moringa Oleifera), Omer I. Fantoukh

Electronic Theses and Dissertations

The first chapter discusses the significance of natural products, safety challenges, and quality issues concisely. Specifically, the impact of herb-drug interaction on consumers and the quest for chemical markers for chemical fingerprinting development are provided. Rooibos tea (Aspalathus linearis) is a popular South African herbal tea enjoyed worldwide. Limited reports indicate the potential of rooibos tea to alter the activity of CYP450 isozymes. In chapter two, the phytochemical investigation of A. linearis resulted in the isolation and characterization of 14 phenolic compounds. Safety assessment of the phytochemicals through interaction with CYP, PXR, and P gp was conducted. The …

Expression Of Tumor Necrosis Factor-Alpha In A Chick Model Of Stress Vulnerable, Treatment – Resistant Depression, Mary Katherine Jourdan

Electronic Theses and Dissertations

An increasing body of literature suggests a Major Depressive Disorder subpopulation, Treatment Resistant Depression (TRD), is associated with an increased immune response. More than a decade of research has identified and begun to validate a novel animal model of TRD. This study sought to determine whether TNF-α levels would be altered due to isolation stress and differentiated between stress-vulnerable and -resilient strains. Black Australorp and Production Red chicks were placed into isolation for varying times during which Distress Vocalization (dVoc) rates were calculated and transformed into entry into behavioral despair percent thresholds. Blood levels of TNF- α were quantified via …