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Prospective Associations Of Homocysteine, Executive Function, And Depressive Symptoms, Peter J. Dearborn Dec 2017

Prospective Associations Of Homocysteine, Executive Function, And Depressive Symptoms, Peter J. Dearborn

Electronic Theses and Dissertations

Associations of cardiovascular risk factors, cognitive performance, and depressive symptoms have been well established. However, the directionality of these associations as well as the specificity of these associations with respect to executive function are less clear. Additionally few studies have determined whether genetic risk factors, such as apolipoprotein-E4 (APOE-E4) genotype, and age moderate the associations of cardiovascular risk factors such as homocysteine with changes in depressive symptoms and how these associations may be mediated by cognitive performance. The primary aim of this study was to analyze the bidirectional associations of a full range of cognitive domains and symptoms of depression …


This Is Just A Phase : The Impact Of Population Structure On Haplotype Phasing And Linkage Disequilibrium Measures At Functional Genetic Sites., Roxanne Kaaren Leiter Dec 2017

This Is Just A Phase : The Impact Of Population Structure On Haplotype Phasing And Linkage Disequilibrium Measures At Functional Genetic Sites., Roxanne Kaaren Leiter

Electronic Theses and Dissertations

The block-like structure of the human genome has been the subject of many scientific papers and is of practical significance in large-scale genome-wide association studies. How stringent haplotype block boundaries are within and between populations has been the subject of ongoing debate within human population genetics. This thesis will contribute to the description of universal and population-specific haplotype blocks at functional sites, namely across the IL-10 gene family (including IL-10, IL-19, IL-20 and IL-24), which is involved in a number of immune system processes, and MAPKAP-K2, an adjacent and functionally significant kinase gene. Beyond the description of blocks across these …


Molecular And Pathological Analyses Of Three New Mouse Mutations That Affect Ear Development And Function, Cong Tian Aug 2017

Molecular And Pathological Analyses Of Three New Mouse Mutations That Affect Ear Development And Function, Cong Tian

Electronic Theses and Dissertations

This dissertation presents three new mouse models that help to study the functions of Enpp1, Atp6v1b1, and Tbx1 for ear development and function. asj (aging with stiffened joints) carries a missense mutation in the mouse Enpp1 gene. Enpp1 encodes the enzyme ENPP1 that regulate soft-tissue calcification and bone mineralization, and is associated with generalized arterial calcification of infancy and hypophosphatemic rickets in human patients. asj mutant mice show severe middle ear infection and tissue calcification, which provide a new mouse model to study otitis media and tympanoscleorosis. Atp6v1b1 encode a protein that is a subunit of the V-ATPase …


The Dlk1-Meg3 Locus In Malignant Cells Of Proposed Primordial Germ Cell Origins., Zachariah Payne Sellers Aug 2017

The Dlk1-Meg3 Locus In Malignant Cells Of Proposed Primordial Germ Cell Origins., Zachariah Payne Sellers

Electronic Theses and Dissertations

Primordial germ cells (PGCs) are hypothesized to deposit hematopoietic stem cells (HSCs) along their migration route through the embryo during the early stages of embryogenesis. PGCs also undergo global chromatin remodeling, including the erasure and reestablishment of genomic imprints, during this migration. While PGCs do not spontaneously form teratomas, their malignant development into germ cell tumors (GCTs) in vivo is often accompanied by the retention of hypomethylation at the IGF2-H19 imprinting control differentially methylated region (DMR). Previous studies in bimaternal embryos determined that proper genomic imprinting at two paternally imprinted loci was necessary for their growth and development: Igf2-H19 and …


Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow Aug 2017

Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow

Electronic Theses and Dissertations

Cystic fibrosis (CF) is a genetic disorder that affects 30,000 people in the United States and currently has no cure. Although CF affects all of the body’s systems, it is largely characterized as a lung disease. CF is caused by a mutation in both copies of the gene for cystic fibrosis transmembrane conductance regulator (CFTR). A mutation in the CFTR gene leads to improper movement of chloride ions and water into the airways, which dysregulates the airway surface liquid volume and composition. Individuals with CF are prone to lung infections due to inefficient bacterial clearance and by the age of …


The Biogeographic Origins And Trophic Ecology Of Maine’S Island Red-Backed Salamanders (Plethodon Cinereus), Nikko-Ideen Shaidani May 2017

The Biogeographic Origins And Trophic Ecology Of Maine’S Island Red-Backed Salamanders (Plethodon Cinereus), Nikko-Ideen Shaidani

Electronic Theses and Dissertations

Island populations of terrestrial species have an increased potential, compared to mainland populations, to adapt and diverge, as these populations often are isolated with respect to gene flow from other populations and may be subjected to novel pressures. Indeed, extended isolation of individuals can elicit dramatic changes within populations and is recognized as a common driver of speciation. It is for these reasons that island populations are often a priority for conservation. Plethodontid salamanders are among the most terrestrial of Maine’s amphibians and are not tolerant of prolonged exposure to seawater, and yet, they are found on a number of …


Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May May 2017

Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May

Electronic Theses and Dissertations

In this study, we compared the osmotic stress response of larval and juvenile blue mussels (Mytilus edulis) at the transcriptomic, metabolomic, and whole organism levels. Blue mussels inhabit coastal areas, where they face climate-induced reductions in nearshore salinity. Despite their ecological and economic importance, scientists do not fully understand the underlying transcriptomic and cellular mechanisms of the osmotic stress response in blue mussels or how the ability to respond to stress changes throughout development. Blue mussels spend the first weeks of life developing through several larval stages in the plankton. These early life history stages are more vulnerable …


Denoising Tandem Mass Spectrometry Data, Felix Offei May 2017

Denoising Tandem Mass Spectrometry Data, Felix Offei

Electronic Theses and Dissertations

Protein identification using tandem mass spectrometry (MS/MS) has proven to be an effective way to identify proteins in a biological sample. An observed spectrum is constructed from the data produced by the tandem mass spectrometer. A protein can be identified if the observed spectrum aligns with the theoretical spectrum. However, data generated by the tandem mass spectrometer are affected by errors thus making protein identification challenging in the field of proteomics. Some of these errors include wrong calibration of the instrument, instrument distortion and noise. In this thesis, we present a pre-processing method, which focuses on the removal of noisy …


Function Of The Enterobactin Operon Of A. Actinomycetemcomitans In The Presence Of Catecholmines And Iron., Taylor Johnson May 2017

Function Of The Enterobactin Operon Of A. Actinomycetemcomitans In The Presence Of Catecholmines And Iron., Taylor Johnson

Electronic Theses and Dissertations

Background: Aggregatibacter actinomycetemcomitans (Aa) possesses a two-component system, QseBC, which is key in biofilm formation/virulence and is activated in the presence of iron-catecholamine complexes. Aa does not synthesize enterobactin, a catechol-based siderophore, yet possesses the machinery for recognition and uptake. We hypothesize that Aa is able to acquire iron by catecholamine mediation through the enterobactin receptor/transporter. Methods: By insertional mutation, we attempted to delete the enterobactin permease from the genome using suicide vector pJT1. A growth curve of truncated mutant ΔfepA was also conducted to observe growth in the presence of iron and catecholamines. Statistical significance was determined by ANOVA …


Dna Metabarcoding Reveals Provisioning Of Pollution-Sensitive Aquatic Insects, Resource Partitioning, And Dietary Shifts Among Breeding Neotropical Migratory Songbirds In A Riparian Habitat, Brian K. Trevelline Jan 2017

Dna Metabarcoding Reveals Provisioning Of Pollution-Sensitive Aquatic Insects, Resource Partitioning, And Dietary Shifts Among Breeding Neotropical Migratory Songbirds In A Riparian Habitat, Brian K. Trevelline

Electronic Theses and Dissertations

Elucidating the diet of Neotropical migratory birds is essential to our understanding of their ecology and to their long-term conservation. Beyond broad taxonomic or morphological categories, however, the diet of Neotropical migrants is poorly documented. Using the molecular techniques of DNA barcoding and next-generation sequencing, we elucidated the diet of Neotropical migratory songbirds breeding in the riparian zones of headwater Appalachian streams. This approach resulted in a genus- or species-level description of diets that improved the current understanding of how songbirds utilize aquatic prey resources in riparian habitats. Furthermore, our approach revealed that breeding songbirds partition prey resources within a …


Distribution Changes, Genetic Population Structure, And A Novel Environmental Dna (Edna) Detection Method For Darters (Subgenus Nothonotus) In The Upper Ohio River Watershed, Anthony S. Honick Jan 2017

Distribution Changes, Genetic Population Structure, And A Novel Environmental Dna (Edna) Detection Method For Darters (Subgenus Nothonotus) In The Upper Ohio River Watershed, Anthony S. Honick

Electronic Theses and Dissertations

In the upper Ohio River watershed three species of small-bodied benthic fish the Bluebreast Darter, Etheostoma (Nothonotus) camurum (Cope), the Tippecanoe Darter, Etheostoma (Nothonotus) tippecanoe Jordan and Evermann, and the Spotted Darter, Etheostoma (Nothonotus) maculatum Kirtland previously existed in disjunct distributions due to poor water quality and habitat degradation. Signs of recovery indicated that these species were moving from areas of refugia into the deeper mainstem waters of the Allegheny and Ohio rivers and expanding their distributions. To provide information for the proper conservation management of these species this dissertation was divided into three stages: 1) distribution records were updated …


Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr Jan 2017

Evolutionary Linkage Of Mimetic And Non-Mimetic Color Traits In A Coral Snake Mimicry Complex, John D. Curlis Jr

Electronic Theses and Dissertations

Color polymorphism in aposematic mimicry systems is a perplexing phenomenon for evolutionary biologists, as theoretically the benefits of converging on a model phenotype should constrain the evolution of phenotypic diversity in these systems (i.e., color polymorphism should not occur). Nevertheless, color polymorphism in mimicry systems is prevalent throughout many taxa. In some of these systems, the evolution of color polymorphism results in the existence of non-mimetic morphs, such as those that are cryptic. The case of ground snakes (Sonora semiannulata) is unique in that color polymorphism encompasses both mimetic and cryptic morphs, as well as individual mimetic and …


Improvement Of Milling And Nutritional Quality Characteristics Of Oats Through Genomic Selection, Sudha Neupane Adhikari Jan 2017

Improvement Of Milling And Nutritional Quality Characteristics Of Oats Through Genomic Selection, Sudha Neupane Adhikari

Electronic Theses and Dissertations

Oats can lower cholesterol, reduce risks of type-2 diabetes, and help prevent heart diseases when consumed daily. Therefore, it is important to evaluate and select breeding lines with desirable milling and nutritional quality traits. Genomic selection, which uses genotyping data to predict the breeding value of an individual, is a promising method to increase genetic gain by selecting for quality traits earlier in the line development process. In this study, we collected phenotypic data for three nutritional traits (protein, β- glucan, and fat content) and five milling quality traits (percent plumps, percent thins, percent plump groat, groat percent and thousand …


Using Rna Seq To Define Genes And Pathways Affecting Salmonella Vaccine Response In Beef Cattle, Sara Awrahman Jan 2017

Using Rna Seq To Define Genes And Pathways Affecting Salmonella Vaccine Response In Beef Cattle, Sara Awrahman

Electronic Theses and Dissertations

A Salmonella siderophore receptor and porin (SRP) proteins vaccine is an intervention strategy to control Salmonella burden in cattle. The vaccine works by stimulating immunity to produce antibodies against bacterial SRPs as siderophore molecules play a major role in transporting iron to bacteria. Blocking iron uptake system by antibodies causes death of bacterial cells. The vaccine can also be useful to protect humans against salmonellosis, which causes high rates of illness and death annually, by reducing shedding of Salmonella in the feces of cattle. Though other researchers have evaluated efficacy and immune response of this Salmonella SRP vaccine, genes …


Small Rho Gtpase Family Member Cdc42 And Its Role In Neuronal Survival And Apoptosis, Noelle Christine Punessen Jan 2017

Small Rho Gtpase Family Member Cdc42 And Its Role In Neuronal Survival And Apoptosis, Noelle Christine Punessen

Electronic Theses and Dissertations

Neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), Alzheimer's and Parkinson's disease are caused by a progressive and aberrant destruction of neurons in the brain and spinal cord. These disorders lack effective long term treatments, and existing options focus primarily on either delaying disease onset or alleviating symptomology. Dysregulated programmed cell death, known as apoptosis, is one of the most significant contributors to neurodegeneration, and is controlled by a number of different factors. Rho GTPases are a protein class with recognized importance in proper neuronal development and migration, and have more recently emerged as regulators of apoptosis and neuronal survival. …


Dynamics Of Gene Networks In Cancer Research, Paul Scott Jan 2017

Dynamics Of Gene Networks In Cancer Research, Paul Scott

Electronic Theses and Dissertations

Cancer prevention treatments are being researched to see if an optimized treatment schedule would decrease the likelihood of a person being diagnosed with cancer. To do this we are looking at genes involved in the cell cycle and how they interact with one another. Through each gene expression during the life of a normal cell we get an understanding of the gene interactions and test these against those of a cancerous cell. First we construct a simplified network model of the normal gene network. Once we have this model we translate it into a transition matrix and force changes on …


A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt Jan 2017

A Population Genetic Investigation Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi) On Eglin Air Force Base, Alexander S. Wendt

Electronic Theses and Dissertations

The reticulated flatwoods salamander (RFS) is an endangered salamander with a unique life history. One of the largest known, best studied refuges for RFS is found on Eglin Air Force Base, and these RFS have been sampled and managed extensively since 2010. My thesis seeks to better understand RFS by using genetic techniques to address several unknowns, including: 1) determining the population structuring of RFS and the manageable units for species conservation, 2) estimating the size and status of populations, 3) understanding dispersal of RFS and factors that influence this, 4) exploring the breeding biology and recruitment patterns of RFS …