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Population Structure, Genetic Diversity, Geographic Distribution, And Morphology Of Two Boechera (Brassicaceae) Parental Species (Boechera Thompsonii And Boechera Formosa) And Of Their Resultant Hybrid Boechera Duchesnensis, Christina Elizabeth Fox Call

Theses and Dissertations

Background: Over the relatively short period of its evolutionary history, Boechera (Brassicaceae) has undergone rapid radiation that has produced 70+ morphologically distinct, sexual diploids. However, reproductive isolation has moved more slowly than morphological divergence in this group and the diploids appear to hybridize frequently where they coexist. Boechera duchesnensis appears to be the result of hybridization between its putative parents Boechera thompsonii and Boechera formosa. Objectives: The objectives of this study are to (i) analyze and document genetic diversity patterns in the population structure, - including allelic and heterozygosity frequencies - of B. thompsonii and B. formosa …

The Influence Of Fine Particulate Matter On Inflammatory Bowel Disease In South Carolina: An Ecological Analysis, Joshua Eric Sellner

Theses and Dissertations

Background. The Inflammatory Bowel Diseases, including both Ulcerative Colitis and Crohn’s Disease, are lifelong disorders of the Gastrointestinal tract. In recent years, both conditions have become much more prevalent and recognized as major public health issues. Environmental factors have become the focus of recent research around the cause of these diseases. Although shown to have detrimental effects on diseases similar to that of the Inflammatory Bowel Diseases, fine particulate matter’s role in these diseases has not been adequately investigated.

Aim. The purpose of this study was to test the relation of fine particulate matter with hospitalizations attributable to …

Integration Of Multispectral Camera Systems For Enhanced Visualization Biological Studies Using Uas, Subin Shahukhal

Theses and Dissertations

The purpose of this research is to enhance visualization of warm-blooded animals and analyze the vegetation in which they are located using a camera system mounted on Unmanned Aircraft System (UAS). The results are coherently displayed in a single image at the same spatial location so that biologists will have accurate animal counts along with vegetation conditions. Application of aerial imagery has been used to analyze the vegetation health and determining the number of the animals by the wildlife service. However, a major obstacle of the research is to combine the two imaging systems to obtain the same spatial image …

From Seed To Sky: Impacts Of Explosive Compounds On Vegetation Across Spatial And Developmental Scales, Stephen M. Via

Theses and Dissertations

Explosive compounds are broadly distributed across the globe as a result of nearly two centuries of munitions use in warfare and military activities. Two explosive compounds have seen disproportionate use; RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl- 1,3,5-trinitrobenzene), being the most commonly found explosives in the environment. The effects of explosives on biota have been studied in great detail; however, there is a general lack of understanding with regard to broader ecological impacts of these contaminants. My dissertation objective was to follow the impacts of explosive compounds on vegetation across scales. Impacts on vegetation at the species scale alter community composition via …

Valuing Natural Space And Landscape Fragmentation In Richmond, Va, Lee Wyatt Carpenter

Theses and Dissertations

Hedonic pricing methods and GIS (Geographic Information Systems) were used to evaluate relationships between sale price of single family homes and landscape fragmentation and natural land cover. Spatial regression analyses found that sale prices increase as landscapes become less fragmented and the amount of natural land cover around a home increases. The projected growth in population and employment in the Richmond, Virginia region and subsequent increases in land development and landscape fragmentation presents a challenge to sustaining intact healthy ecosystems in the Richmond region. Spatial regression analyses helped illuminate how land cover patterns influence sale prices and landscape patterns that …

Dietary Patterns And Prostate Cancer Aggressiveness In African-American And European-American Men, Lara Ryan Schneider

Theses and Dissertations

Several foods and nutrients have been linked to prostate cancer risk, but the effect of overall diet on prostate cancer outcomes is not well understood. Previous research has primarily examined a posteriori dietary patterns in relation to prostate cancer; studies that have used a priori dietary patterns and their relationship with prostate cancer have been inconclusive. Furthermore, racial differences in prostate cancer incidence and aggressiveness are not well understood. Data from the case-only North Carolina-Louisiana Prostate Cancer Project (PCaP) was used to examine the association between overall dietary pattern, as measured by the Mediterranean Diet (MED) score and the Dietary …

Allelopathy In The Non-Native Macrophyte, Myriophyllum Spicatum And Its Influence On Trophic Dynamics In Aquatic Systems, Daniel J. Sullivan

Theses and Dissertations

Non-native macrophytes structurally impact aquatic assemblages, yet little is known regarding how they influence energy pathways in freshwater ecosystems. Allelopathy in Eurasian watermilfoil- Myriophyllum spicatum has been shown to target basal epiphytic organisms resulting in differences in assemblage structure of colonizing epiphyton between M. spicatum and native M. sibiricum. I conducted a growth chamber experiment to investigate the hypothesis that differences in assemblage structure of colonizing epiphyton between these two macrophytes influence trophic dynamics within aquatic systems. My data suggest M. spicatum produces higher concentrations of allelochemicals, resulting in a more diverse epiphytic assemblage compared to M. sibiricum. This could …

Effects Of Intercropping Switchgrass In Managed Pine Stands On Plant Communities And White-Tailed Deer Forage Production, Bradley Robert Wheat

Theses and Dissertations

Interest in renewable energy and governmental mandates has motivated land managers to consider cellulosic feedstocks for bioenergy. I investigated plant community response to a system including switchgrass (Panicum virgatum) as a feedstock intercropped with loblolly pine (Pinus taeda). I estimated plant species evenness, richness, and diversity and biomass production, with emphasis on white-tailed deer (Odocoileus virginianus) forages. I detected 225 species in 2,220 1-m2 quadrats, and 7,495 biomass samples (96.4 kg dry weight) from 960 quadrats. Intercropping reduced plant species diversity, total non-pine tree biomass, and biomass of deer forages during switchgrass establishment. These effects were no longer apparent at …

Modeling Tree Species Distribution And Dynamics Under A Changing Climate, Natural Disturbances, And Harvest Alternatives In The Southern United States, Zhen Sui

Theses and Dissertations

Forests in the southern United States with diverse forest ownership entities are facing threats associated with climate change and natural disturbances. This study represented the relationship between climate and species dominance, predicted future species distribution probability under a changing climate, and projected forest dynamics under ownership-based management regimes. Correlative statistics and mechanistic modeling approaches are implemented. Temporal scale includes the recent past 40 years and the future 60 years; spatial scale downscaled from southern United States to the coastal region of the northern Gulf of Mexico. In the southern United States, dominance of four major pine species experienced shifts from …

Genetic Structure Of Rhizobia Associated With Chamaecrista Fasciulata, Hanna Elizabeth Dorman

Theses and Dissertations

The legume-rhizobia relationship is an important symbiosis. Studies have found variation in specificity and the functionality of symbiotic specificity can vary among plants of the same species and among rhizobia, as well as in concert with geographical variation. Here, we examined the diversity and geographic structure of rhizobia nodulating Chamaecrista fasciculata, which grows throughout the east-central U.S. and is symbiotic with Bradyrhizobium species. We investigated the association of geography and soil variables on rhizobial diversity by sampling plant nodules and soil across Mississippi and evaluated variation in rhizobia housed in different nodules of individual plants. Using nifH and truA, we …

Ecological, Localization And Functional Analysis Of Two Lysosomal Enzymes In Dictyostelium Discoideum, Sanaa Talib Jawed

Theses and Dissertations

Dictyostelium discoideum is a primitive eukaryote that has recognized useful in studying various aspects of lysosomal enzymes as well as development since it can differentiate from unicellular amoebae into a multicellular.In this study, we investigated the localization, ecological and molecular function of two lysosomal enzymes, hexosaminidase (NagA) and,,-glucosidase (GluA) proteins, by overexpressing the genes encoding them in D. discoideum. Separate cell-lines overexpressing a GFP-tagged versions of the full length DdNagA gene (GFP-NagA), mutant version of the NagA gene (GFP-NagA (N214S)), a GFP-tagged version of the full length DdGluA gene (GFP-GluA) and a mutant version of first 83 amino acids DdGluA …

High Salinity Stabilizes Bacterial Community Composition And Activity Through Time, Tylan Wayne Magnusson

Theses and Dissertations

Dormancy is a plausible strategy for bacteria to overcome the effects of temporal fluctuations in resources or stresses and await more “optimal” conditions to resume metabolic activity and growth. Seasonal changes in environmental conditions force microbes to adjust their metabolic activity accordingly, and community composition drastically shifts. In extreme environments, however, the overriding effects of a constant stress may constrain the need or benefit of bacteria entering dormancy. In hypersaline lakes, high metabolic activity is required to maintain adaptations that permit survival. Sampling from six lakes on a salinity gradient (0.05% – 30.3%), we measured seasonal fluctuations in bacterial dormancy …

Spatial Genetic Structure Of Hatchlings Of Cyclura Ricordii (Reptilia: Iguanidae) In Pedernales Province, Dominican Republic Is Inconsistent With Natal Philopatry, Rosanna Carrerase De Leon

Theses and Dissertations

Cyclura ricordii is an endemic iguana from Hispaniola and is listed as Critically Endangered on the IUCN. The main threats are predation by introduced mammals, habitat destruction and hunting. The present study focused on two nesting areas in Pedernales in the Dominican Republic. The hypothesis tested is that natal philopatry influences dispersal and nest site selection. Monitoring and sampling took place during 2012-2013. Polymorphic markers were used to evaluate whether natal philopatry limits dispersal at multiple spatial scales. Ripley’s K, revealed that nests were significantly clustered. Hierarchical AMOVA revealed that nest site aggregations did not explain a significant portion of …

The "Isolated Find" Concept And Its Consequences In Public Archaeology, Jesse Morton

Theses and Dissertations

The term “isolated find” has frequently been taken as a disposable artifact category in cultural resource management (CRM). Efforts were made to empirically demonstrate the fallacy of this concept and its use, using modified field sampling strategies, the inclusion of fine screen artifact analysis, and statistical analyses. Six sites containing prehistoric occupations on Camp McCain National Guard base in Grenada County, Mississippi were reinvestigated using these methods; their datasets were expanded in terms of site size, density, function, and temporal association, which may change their eligibility status for the National Register of Historic Places (NRHP). Fieldwork and classification based solutions …

The Effects Of Income Inequality On Society, Jessica Lee Clark

Theses and Dissertations

This study is an examination of the relationship between income inequality and numerous indicators that capture the physical health of the citizens, additionally controlling for numerous other confounding factors. The analysis contributes to the literature by examining this relationship at a more disaggregated level within the Unites States than previous studies. This approach may help us to explore any impacts of income inequality on health that are lost in aggregation. The analysis also includes the most recent recession and adds to the literature the impact of inequality on health during a period of economic crisis. Results suggest that there is …

Ixodes Scapularis In North Dakota: Phenology, Population Genetics, And Local Host Reservoir Competency In An Emerging Vector Population, Michael Dougherty

Theses and Dissertations

Tick surveillance in eastern North Dakota has revealed the presence of established I. scapularis populations in fragmented forest habitats previously regarded as unsuitable for this species. Understanding I. scapularis phenology, the reservoir competency of local vertebrate hosts, and population structure of blacklegged ticks in this region is essential to determining potential human risk of Lyme disease. Tick surveys were conducted throughout North Dakota by flagging and small mammal trapping. 1,701 ticks were collected, including 297 I. scapularis exhibiting a relatively low Borrelia burgdorferi infection rate (ca. 3-5%). Seasonal abundance varied greatly among life stages, with adult I. scapularis being most …

Consequences Of Vine Infestation: Linking Abiotic Influences And Biotic Interactions To Successional And Structural Changes In Coastal Communities, Spencer N. Bissett

Theses and Dissertations

Located at the interfaces of terrestrial and marine environments, coastal habitats are inherently vulnerable to the effects of global change. Barrier island systems in particular serve not only as protective buffers against storm events, but also as sentinel ecosystems for observation of the impacts of sea level rise, and of increasing storm frequency and intensity. In the mid-Atlantic region, shrub thickets of Morella species compose the dominant forest community. The often monospecific nature of these plant community assemblages is advantageous to ecological studies and cross-scale applications; the relatively low diversity facilitates transitions between scales. My objective was to investigate the …

Parasites Within Parasites: Transmission And Evolution Of Neorickettsia In Digeneans, Stephen Edward Greiman

Theses and Dissertations

Digeneans are endoparasitic flatworms with complex life cycles that involve two or more different animals as definitive and intermediate hosts. Some digenean species harbor bacterial endosymbionts belonging to the genus Neorickettsia (Order: Rickettsiales, Family: Anaplasmataceae). Neorickettsia occur in all life cycle stages of digeneans and are maintained by vertical transmission. Far from benign however, Neorickettsia may also be transmitted horizontally by digenean parasites to their vertebrate definitive hosts. Once inside, Neorickettsia can infect macrophages and other cell types. For some vertebrate species (e.g. dogs, horses and humans), neorickettsial infections cause severe disease. With a few exceptions, studies of Neorickettsia have …

Linking Photosynthesis Physiology Of Upland Hardwood Reproduction To Ecology And Silviculture In The Arkansas Ozarks, Kutcher K. Cunningham

Theses and Dissertations

Oak (Quercus) forests in the Arkansas Ozarks have been important culturally, ecologically and environmentally for centuries. Historically these forests were fire dependent and dominated by oak species. In the past century, fire suppression and land management have caused these forests to densify. As a result, oaks are increasingly less abundant following disturbance in natural hardwood stands. Many applied ecological studies have explored methods and practices to maintain oak species in newly developing stands. This study attempted to link the mechanistic physiology of oak and non-oak reproduction to the applied ecological work. Varying stand conditions were generated in an undisturbed mature …

Effect Of Primary Care Physician Density On Late Stage Cervical Cancer Diagnosis, Emily Haanschoten

Theses and Dissertations

INTRODUCTION: Late-stage cervical cancer diagnosis is an important contributing factor to the cervical cancer mortality rate. Screening for cervical cancer is a vital tool in reducing the number of late-stage cases, preventing incident cases and reducing mortality. Access to care is often a significant barrier to receiving these services. Women who have no usual source of care report significantly lower percentages of Pap tests than women who have a usual source. South Carolina ranks 13th in the US in cervical cancer incidence and 7th in cervical cancer mortality. South Carolina also struggles with a primary care physician shortage, ranking 39th …

Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson

Theses and Dissertations

Climate change is having demonstrable, worldwide impacts on ecological systems in ways that have modified aspects of organism behavior. Plant phenologies have responded to warmer temperatures in a variety of ways that may have implications for long-term species survival. How germination phenology changes in response to warmer climate is a largely unexplored question yet the ability of a plant to advance or delay germination in unfavorable conditions is critical for survival. Knowing the relative success and timing of germination under different climate regimes is important in understanding whether species can keep pace with the rate of climate change via migration …

The Wandering Spider Guild Of Webb County, Texas, Monica Trevino

Theses and Dissertations

Analysis of 10 years of spider collecting in Webb County, Texas has yielded 549 specimens in 21 genera and 55 species. This study was performed to establish similarities and relationships among wandering spiders of south Texas in Webb County and to identify the members of the wandering spider guild. The families included in this guild are the Clubionidae, Corinnidae, Gnaphosidae, Liocranidae, and Miturgidae. Wet pitfall traps and hand collecting were utilized in the gathering of the specimens. Spiders were identified using the most recent literature and allowed for an examination of the interactions of the members of this guild based …

Expression Of Facultative Den Behavior In Ursidae, Nicholas Lee Fowler

Theses and Dissertations

Many ecological and evolutionary processes have been described underlying natural selection but supporting evidence in wild settings is often lacking and our understanding remains incomplete. Using a multi-scale approach, I investigated expression of facultative den behavior (denning) among and within ursid species. Among species, lack of denning behavior was supported by relaxation of selection pressures of seasonal food availability due to realization of two sources of ecological opportunity; colonization of new habitat and adaptation of key innovations. Of denning species, I found evidence of adaptive ecological plasticity in den chronology among and within populations consistent with relaxed selective pressures influencing …

Linking Individual Biological Outcomes To Resource Use, Christopher Ryan Ayers

Theses and Dissertations

Minimum resource requirements support population persistence; however, ecologists and conservationists often want to identify factors that improve biological outcomes of animals. The population-level approach common in wildlife-resource studies limits our ability to draw inferences about the importance of resources and other factors by failing to link them with individual fitness. Measuring individual-based biological outcomes and resource use helps determine variation in mechanistic relationships between animal fitness and behavior. I suggest using direct metrics of resource use such as food consumption and distance traveled, to avoid errors with estimating resource availability. I summarize these concepts in an analytical framework for modeling …

Investigating Differences In Risk Behaviors Among Rural, Suburban, And Urban Adolescents, Heather Dubendris

Theses and Dissertations

Introduction: According to the World Health Organization, one-third of the disease morbidity and two-thirds of premature deaths among adults are associated with behaviors that can be traced back to adolescence. These include behaviors resulting in unintentional injury, violent behaviors, alcohol, drug, and tobacco use. The purpose of this research was to explore how differing levels of urbanicity affect youth’s engagement in risk behaviors.

Methods: Analysis was done using a nationally representative sample of 9th-12th graders in the 2003 Youth Risk Behavior Survey (YRBS), the most recent year for which urbanicity is available. The main exposure was urbanicity (classified as urban, …

Herbicide Safening To Aid In The Establishment Of Three Native Warm Season Grass Species, Jesse Spencer Smith

Theses and Dissertations

Difficulties with stand establishment are a major factor limiting further agronomic use of native warm season grasses. One significant cause of stand failure is competition with rapidly growing annual weed species during the early development of the perennial native grass. Broad spectrum preemergent herbicides can provide the needed weed control, but only if tolerance exists in the desired grass. Herbicide safeners, synthetic compounds that protect crops from herbicide injury, applied as seed treatments offer a potential strategy to achieving the needed herbicide tolerance where it does not naturally occur. This study tested the efficacy of five herbicide safeners (benoxacor, fenclorim, …

Benthic Macroinvertebrate Subsampling Effort And Taxonomic Resolution For Bioassessments Of Streams In The James River Watershed Of Virginia, Laurel Williams

Theses and Dissertations

Benthic macroinvertebrate diversity influences stream food web dynamics, nutrient cycling and material exchange between the benthos and the water column. Stream bioassessment has moved to the forefront of water quality monitoring in terms of benthic macroinvertebrate diversity in the recent past. The objectives of this study were to determine optimum subsample size and level of taxonomic resolution necessary to accurately and precisely describe macroinvertebrate diversity in streams flowing in the Piedmont province of the James River watershed in Virginia. Forty-nine sampling sites were selected from streams within the Piedmont Physiographic Province of the James River watershed. Ten sites were randomly …

A Maoli-Based Art Education: Ku'u Mau Kuamo'o 'Ōlelo, Raquel Malia Andrus

Theses and Dissertations

Leaders in K-12 education in Hawai'i are increasingly advocating for and utilizing the culture and knowledge of the kānaka Maoli, the native people of these islands, as a context for learning in a variety of curricular disciplines and approaches (Benham & Heck, 1998; Kani'iaupuni, Ledward & Jensen, 2010; Kana'iaupuni & Malone, 2006; Kahakalau, 2004; Meyer, 2004). To expand upon this trend, this thesis uses a combination of autoethnographic and critical indigenous methodologies to present a personal narrative that looks specifically at approaching art education from a Maoli perspective. Through extensive participant/observer reflections, two place-based and culture-based art education experiences are …

Hepatitis B, C Virus And Hiv Co-Infection Among Reported Female Cases In South Carolina, 2004 - 2011: An Epidemiological Analysis Of Pregnancy Outcomes, Afiba Manza-Azele Agovi

Theses and Dissertations

HIV, hepatitis B and C virus (HBV, HCV) are three of the most common blood-borne infections and they continue to be a major public health problem in the United States (US) and globally. It is not well understood if maternal infection with either HBV or HCV has an adverse impact on pregnancy outcomes as findings from previous studies have provided some mixed results. The overall goal of this study was to assess the risk of preterm birth, low birth weight (LBW), small for gestational age (SGA) and admission into neonatal intensive care unit (NICU) for babies born to HBV- and …

Antibiotic Usage In Relation To Resistant Bacterial Infections And Liver And Kidney Cancer Outcomes In South Carolina, Prea Thathiah

Theses and Dissertations

Antibiotics are one of the most beneficial discoveries in medicine and public health. However, the use, overuse, and misuse of these drugs have led to increases in antibiotic resistant bacterial infections (ARI). Furthermore, previous epidemiological studies have linked antibiotic use to breast cancer, but these studies have not included effects on metabolic organs, such as the liver and kidneys. This dissertation investigates the role of antibiotic use in infections and liver and kidney cancers in the state of South Carolina. Using ecological study methods and Poisson regression to determine relative risk ratios, it was found that antibiotic use is a …