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Development Of Novel Organic Nitrogen Nutrient Solutions With Unique Bioreactors For Precision Nutrient Fertigation, Brian Ward Dec 2011

Development Of Novel Organic Nitrogen Nutrient Solutions With Unique Bioreactors For Precision Nutrient Fertigation, Brian Ward

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A fertility study conducted comparing organic nitrogen versus synthetic nitrogen on yield, quality, mineral and phyto-nutrient content of sweet corn under conventional cultural practices.


Composition And Ecophysiological Proficiency Of Tidal Freshwater Forested Wetlands: Investigating Basin, Landscape, And Microtopographic Scales, Jamie Duberstein Dec 2011

Composition And Ecophysiological Proficiency Of Tidal Freshwater Forested Wetlands: Investigating Basin, Landscape, And Microtopographic Scales, Jamie Duberstein

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A hierarchical approach to forest community assessment was conducted by first focusing on landscape associations to edaphic factors among major tidal freshwater forested wetland basins in the Southeast. Four general tree communities exist along coastal rivers in the southeastern United States, based on the most prominent species in each: Water Tupelo, Swamp Tupelo, Dwarf Palmetto, and Cabbage Palm. Microhabitat usage and preference by trees were then examined, both across all species and within species, as related to such factors as coast, presence on rivers with dams, tree community assemblage, relative distance from the river, specific river basin, and microsite availability. …


Thermal Inactivation Of Stress Adapted Pathogens In Compost, Randhir Singh Dec 2011

Thermal Inactivation Of Stress Adapted Pathogens In Compost, Randhir Singh

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In the United States, 1.3 billion tons of animal wastes are produced annually. Disposal of this huge amount of waste on agricultural land without proper treatment is a public health safety issue as animal waste is a potential source of several human pathogens. Therefore, composting of animal wastes is an economical solution to this problem. The high temperature reached during this process also brings about inactivation of pathogens in the waste. However, survival of pathogens has still been reported from different composting studies, indicating the complex nature of this process. The objectives of this study were to: 1) study thermal …


Computational Approaches To Understand Phenotypic Structure And Constitutive Mechanics Relationships Of Single Cells, Scott Wood Dec 2011

Computational Approaches To Understand Phenotypic Structure And Constitutive Mechanics Relationships Of Single Cells, Scott Wood

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The goal of this work is to better understand the relationship between the structure and function of biological cells by simulating their nonlinear mechanical behavior under static and dynamic loading using image structure-based finite element modeling (FEM). Vascular smooth muscle cells (VSMCs) are chosen for this study due to the strong correlation of the geometric arrangement of their structural components on their mechanical behavior and the implications of that behavior on diseases such as atherosclerosis.
VSMCs are modeled here using a linear elastic material model together with truss elements, which simulate the cytoskeletal fiber network that provides the cells with …


Restoring Longleaf Pine (Pinus Palustris) In Loblolly Pine (P. Taeda) Stands On The Coastal Plain Of North Carolina, Huifeng Hu Dec 2011

Restoring Longleaf Pine (Pinus Palustris) In Loblolly Pine (P. Taeda) Stands On The Coastal Plain Of North Carolina, Huifeng Hu

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To support the development of silvicultural protocols for restoring longleaf pine (LLP; Pinus palustris Mill.) and its characteristic herbaceous understory in loblolly pine (LBP; P. taeda L.) stands, a three-year study was conducted on moderately well- and well-drained soils in Onslow County, North Carolina. A replicated field experiment was conducted to test the effects of selected silvicultural treatments on planted LLP seedlings, understory vegetation, and plant resources. Seven canopy treatments included four uniform canopy density treatments defined by target residual basal area [Control, MedBA (9 m2/ha), LowBA (4.5 m2/ha), and Clearcut] and three circular gap treatments defined by area [LG …


Fatty Acids And Lipogenesis In Ruminant Adipocytes, Taber Burns Dec 2011

Fatty Acids And Lipogenesis In Ruminant Adipocytes, Taber Burns

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Obsesity, the excess deposition of white adipose tissue, is a growing problem in the U.S. and other developed countries. Formerly thought to be inert, adipose tissue is now recognized as a dynamic endocrine organ with its secretion of adipokines and a newly proposed class hormone class 'lipokine'. Adipocytes are the functional unit of adipose tissue and can influence the tissue through hyperplasic and hypertrophic growth. In order to investigate the mechanisms involved in adipogenesis and lipogenesis of adipose tissue, stromal vascular cultures were isolated from adipose tissue of finishing cattle for use in experiments.
There is a positive relationship between …


Developing Strategies To Control Human Pathogens In Minimally-Maintained Dairy Manure-Based Compost Heaps, Marion Shepherd Dec 2011

Developing Strategies To Control Human Pathogens In Minimally-Maintained Dairy Manure-Based Compost Heaps, Marion Shepherd

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Composting has been proven to be an effective method used to inactivate pathogens in dairy manure. However, research has shown that if the compost heaps are unturned pathogens can persist, especially on the surface of the heaps for extended periods of time. As such, it is important to evaluate potential interventions that can be used to ensure that pathogens are inactivated at all locations of minimally maintained compost heaps under field conditions. The objectives of this study were to: 1) determine the impact of compost initial carbon-to-nitrogen (C:N) ratio on pathogen destruction when composting dairy manure in unturned heaps, 2) …


Lipid Metabolism In Trypanosoma Brucei: Molecular Characterization Of Fatty Acid Synthesis And Uptake, Patrick Vigueira Aug 2011

Lipid Metabolism In Trypanosoma Brucei: Molecular Characterization Of Fatty Acid Synthesis And Uptake, Patrick Vigueira

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My doctoral studies focused on the fatty acid metabolism of the deadly protozoan parasite, Trypanosoma brucei. Fatty acid metabolism in T. brucei can be broadly divided into two pathways, synthesis and uptake. In Chapters 2-4 I describe experiments investigating the parasite's fatty acid synthesis pathway. Chapter 2 contains the initial characterization of acetyl-CoA carboxylase (ACC) in T. brucei. Knockdown of TbACC by RNA interference (RNAi) reduced parasite virulence in a mouse model, suggesting that TbACC has the potential to be utilized as a drug target. Chapters 3 and 4 explore the effects of two known ACC inhibitors, the …


Biohydrogenation Of Docosahexaenoic Acid, Catherine Klein Aug 2011

Biohydrogenation Of Docosahexaenoic Acid, Catherine Klein

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Pathways of docosahexaenoic (DHA) biohydrogenation are not known; however, DHA is metabolized by ruminal microorganisms. The addition of DHA to the rumen alters the fatty acid profile of the rumen and milk and leads to increased trans-18:1 isomers, particularly trans-11 18:1 and 22 carbon fatty acids. This study included four in vitro experiments to identify if these are produced from DHA or if they come from other sources that are affected by DHA. In each experiment, ruminal microorganisms collected from a lactating Holstein cow were incubated in batch cultures for 0, 6, 24, and 48h and a uniformly 13C DHA …


Predicting Yeast Synthetic Lethal Genetic Interactions Using Protein Domains, Bo Li Aug 2011

Predicting Yeast Synthetic Lethal Genetic Interactions Using Protein Domains, Bo Li

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Synthetic lethal genetic interaction (SLGI) is an important biological phenomenon. Such interactions are of interest as they can be used to predict function of unknown proteins and find drug targets or drug combinations. High throughput biological experiments enhance the capability in identifying genetic interactions, but the large amount of protein pairs still make the task of genome-wide identification of genetic interactions overwhelming. Computational based prediction of SLGIs is promising but still hampered by the unclear molecular mechanism of SLGIs.
Protein domains with conserved functions serve as the building blocks of proteins. The genetic interaction that occurs between a pair of …


Measuring The Impact Of Youth Efnep: Questionnaire Development And Validation, Yenory Hernandez Aug 2011

Measuring The Impact Of Youth Efnep: Questionnaire Development And Validation, Yenory Hernandez

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Background: Given the problem of childhood obesity and food insecurity among low-income children, the Youth Expanded Food and Nutrition Education Program (EFNEP) needs an appropriate, valid and reliable evaluation tool to determine the program effectiveness.
Purpose: To describe the development and preliminary validation of EFNEP Youth Quest questionnaire, an impact assessment tool designed for Youth EFNEP program.
Use of theory: The Community Nutrition Education logic model adapted with constructs of Social Cognitive Theory and Theory of Planned Behavior.
Targeted audience: Low income-ethnically diverse children, in third, fourth and fifth grade.
Design: The development of the questionnaire included six phases: preliminary …


Influence Of The Postharvest Environment On The Storage Potential And Propagation Performance Of Unrooted Cuttings Of Herbaceous Ornamentals, Amy Enfield Aug 2011

Influence Of The Postharvest Environment On The Storage Potential And Propagation Performance Of Unrooted Cuttings Of Herbaceous Ornamentals, Amy Enfield

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Plants propagated from vegetative cuttings have become an increasingly important market in the United States. Significant economic losses occur annually due to poor performance, damage or death of cuttings. This occurs in large part due to the industry's lack of knowledge of the proper postharvest environments to provide to cuttings. This project was conducted to improve the understanding of the postharvest physiology of unrooted cuttings in order to optimize performance and longevity. Experiments were conducted to quantify the effect of temperature on respiration and ethylene production rates of unrooted cuttings. Additionally, the effect of the stock plant environment on the …


Population Genetics And Species Interactions: From Theory To Agro-Ecosystems, Cynthia Climer Aug 2011

Population Genetics And Species Interactions: From Theory To Agro-Ecosystems, Cynthia Climer

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Population genetics is the study of allele frequency distributions and changes due to evolutionary processes such as selection, adaptation, genetic drift and gene flow to understand how these processes impact populations over space and time. Population genetics theory can be utilized to understand not only population level interactions, but also interactions among closely related species. In this dissertation I have utilized population genetics in three conceptually related projects. Utilizing genome-wide gene coding markers, I have tested the impact of population size changes on the genetic diversity of coding genes in a model system (Arabidopsis lyrata subsp. petraea). This study tests …


Investigations Of The Ppi-Dependent Acetate Kinase From The Parasite Entamoeba Histolytica, Matthew Fowler Aug 2011

Investigations Of The Ppi-Dependent Acetate Kinase From The Parasite Entamoeba Histolytica, Matthew Fowler

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Acetate, a short-chain fatty acid that plays a key role in all domains of life, can be utilized as a carbon source or excreted as a product of metabolism. Acetate kinase (ACK), a member of the acetate and sugar kinase-Hsp70-actin (ASKHA) enzyme superfamily, is responsible for the reversible phosphorylation of acetate to acetyl phosphate utilizing ATP as the phosphoryl donor. Acetate kinases are ubiquitous in the Bacteria, found in one genus of Archaea, and are also present in microbes of the Eukarya. A partially purified ACK which can utilize pyrophosphate (PPi) as the phosphoryl donor in the acetyl …


Effect Of Goldenseal (Hydrastis Canadensis) On Bacterial Multi Drug Resistant Efflux Pumps, Jyothi Rangineni Aug 2011

Effect Of Goldenseal (Hydrastis Canadensis) On Bacterial Multi Drug Resistant Efflux Pumps, Jyothi Rangineni

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Multi-Drug Resistance (MDR) efflux pumps have been increasingly reported in Gram negative and Gram positive bacteria. These efflux mechanisms pump out a wide variety of structurally unrelated antimicrobials thus leading to a low susceptibility due to lowered intracellular concentrations. The activity of such antimicrobials can be restored by the inhibition of the multi drug efflux pumps. Several MDR pump inhibitors which inhibit the efflux mechanisms in bacteria have been identified. Reserpine and verapamil are two such inhibitors, showing considerable effect on the MDR pumps. But the concentrations required to achieve these effects are too high to be clinically relevant. Reserpine …


Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten Aug 2011

Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten

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Zoos are a unique environment where humans and animals are in close daily contact, potential mosquito habitats exist, exotic plants and animals are introduced regularly, and wild animals roam. Studies of mosquito behaviors in zoos will lead to a better understanding, both within and outside zoos, of disease transmission routes and mosquito biology. To investigate whether the unique assemblage of habitats in zoos affects mosquito behavior, I sampled larvae and adults in the Greenville Zoo and the Riverbanks Zoo, South Carolina, USA, from March 2008 to January 2011. The objectives of my study were to investigate mosquito oviposition behavior, blood-host …


A Survey Of Heterologous Expression Systems For The Production Of Bovine Follicle Stimulating Hormone And Luteinizing Hormone, Marcia Hesser May 2011

A Survey Of Heterologous Expression Systems For The Production Of Bovine Follicle Stimulating Hormone And Luteinizing Hormone, Marcia Hesser

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Follicle stimulating hormone (FSH) and luteinizing hormone (LH) are glycoprotein gonadotropins from the anterior pituitary gland that are involved in reproductive functions. They are heterodimeric proteins that share a common α-subunit that is highly conserved amongst mammalian species, and is also conserved across this family of proteins. The β-subunit confers receptor specificity and is distinct. Recombinant gonadotropin expression would be an important advance for the bovine superovulation industry, as there are a number of disadvantages associated with the currently used pituitary-derived gonadotropins. For example, these pituitary products are contaminated with other proteins including hormones, exhibit batch-to-batch inconsistencies, and harbor the …


Activities Of Muscadine Grape Skin And Polyphenolic Constituents Against Helicobacter Pylori, Joseph Brown May 2011

Activities Of Muscadine Grape Skin And Polyphenolic Constituents Against Helicobacter Pylori, Joseph Brown

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Helicobacter pylori is a microaerophilic, gram-negative bacterium and among the most persistent of all human pathogens. Its presence in the gastric environment is corre-lated with diseases such as gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric carcinoma. Multiple factors are believed responsible for disease progression and outcome including infecting strain(s) genetic composition, age of acqui-sition, host immune response, environment, and diet. Due to the complexity of H. pylori infection, all possible host-pathogen interactions should be considered. One important factor frequently underplayed is host dietary habits which may serve a more important role during and immediately following infection with H. …


Characterization Of Piedmont Prairie Sites In North And South Carolina, James Benson May 2011

Characterization Of Piedmont Prairie Sites In North And South Carolina, James Benson

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Grassland habitats have essentially disappeared from the Piedmont. This study was conducted to determine which site characteristics in remnant Piedmont prairie sites could be used as indicators of suitable sites. Eight prairie remnant sites located in the Piedmont of North and South Carolina were evaluated based on soil series, slope, aspect, landform index, temperature, and precipitation. Geographic Information System technology was used to create layers of these characteristics to predict potential restoration sites throughout the North and South Carolina Piedmont. It was found that southern aspects, slopes generally less than 15%, upper slope positions, and occurrence on Enon (Fine, mixed, …


Comparative Forelimb Muscle Function In Turtles: Tests Of Environmental Variation And Neuromotor Conservation, Angela Rivera May 2011

Comparative Forelimb Muscle Function In Turtles: Tests Of Environmental Variation And Neuromotor Conservation, Angela Rivera

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Novel locomotor functions in animals may evolve through changes in morphology, muscle activity, or a combination of both. The idea that new functions or behaviors can arise solely through changes in structure, without concurrent changes in the patterns of muscle activity that control movement of those structures, has been formalized as the `neuromotor conservation hypothesis'. In vertebrate locomotor systems, evidence for neuromotor conservation is found across transitions in terrestrial species and into fliers, but transitions in aquatic species have received little comparable study to determine if changes in morphology and muscle function were coordinated through the evolution of new locomotor …


Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson May 2011

Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson

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The functional role of piezoelectricity and of other modes of electromechanical coupling across the hierarchical structures of biological materials garnered interest many years ago. Many biological materials have been described as exhibiting piezoelectric behavior, from wool fibers to wood planks and even to living mammalian cells, but efforts are on-going towards understanding how electromechanical coupling in biological systems transcends from the molecular to tissue levels.
In pursuit of high-resolution measurements of such hierarchical electromechanical coupling, scanning probe microscopy-based techniques are considered. Piezoresponse force microscopy (PFM) becomes the specific focus of this work, and the nascent development of PFM is reviewed …


Regulation Of Trypanosoma Brucei Hexokinase 1 And 2 On Multiple Levels: Transcript Abundance, Protein Expression And Enzyme Activity, Heidi Dodson May 2011

Regulation Of Trypanosoma Brucei Hexokinase 1 And 2 On Multiple Levels: Transcript Abundance, Protein Expression And Enzyme Activity, Heidi Dodson

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Trypanosoma brucei, a unicellular eukaryotic parasite, is the causative agent of African sleeping sickness in sub-Saharan Africa. The parasite encounters two main environments as it progresses through its life cycle: the tsetse fly and the mammalian
bloodstream. Nutrient availability is distinct in the two environments, requiring the parasite to utilize diverse metabolic pathways to efficiently produce ATP for survival. Bloodstream form parasites (BSF), residing in a glucose rich environment, rely solely on
glycolysis for energy, while procyclic form (PF) parasites metabolize readily available proline and threonine in addition to glucose.
T. brucei expresses two hexokinases, the first enzyme in the …


An Ecological, Genetic, And Reproductive Study Of Big Bluestem (Andropogon Gerardii) Populations In The Carolinas, Robert Tompkins May 2011

An Ecological, Genetic, And Reproductive Study Of Big Bluestem (Andropogon Gerardii) Populations In The Carolinas, Robert Tompkins

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ABSTRACT
AN ECOLOGICAL, GENETIC, AND REPRODUCTIVE STUDY OF BIG BLUESTEM (ANDROPOGON GERARDII) POPULATIONS IN THE CAROLINAS
Andropogon gerardii (Big Bluestem) is a dominant grass of the North American tallgrass prairie and is also found in remnant populations in the eastern U.S., including North and South Carolina. This research included a systematic study of the ecology, genetics, and reproductive potential within and among A. gerardii populations in the Carolinas. Floristic composition and edaphic (soil) features were characterized for eight A. gerardii populations across various physiographic regions of North and South Carolina. A total of 362 quadrats (1 m x 1 m) …


Ecosystem Responses To Fuel Reduction Treatments In Stands Killed By Southern Pine Beetle, Aaron Stottlemyer May 2011

Ecosystem Responses To Fuel Reduction Treatments In Stands Killed By Southern Pine Beetle, Aaron Stottlemyer

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Heavy fuel loads were created by multiple southern pine beetle (Dendroctonus frontalis Ehrh.) outbreaks throughout the southern Piedmont between 1999 and 2002. Prescribed burning and mechanical mastication are proposed to reduce fuel loading in beetle-killed pine (Pinus L. spp.) stands in the upper South Carolina Piedmont, but their ecological impacts are unknown. Prescribed burning reduced fuelbed continuity by consuming litter (Oi) and fine (1- and 10-hr timelag size classes) woody fuels immediately after the treatment. Duff (Oe + Oa) layer thickness also decreased and mineral soil was exposed in some areas. Mastication resulted in a thick, continuous layer of shredded …


Pretictive Bioinformatic Methods For Analyzing Genes And Proteins, Shaolei Teng May 2011

Pretictive Bioinformatic Methods For Analyzing Genes And Proteins, Shaolei Teng

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Since large amounts of biological data are generated using various high-throughput technologies, efficient computational methods are important for understanding the biological meanings behind the complex data. Machine learning is particularly appealing for biological knowledge discovery. Tissue-specific gene expression and protein sumoylation play essential roles in the cell and are implicated in many human diseases. Protein destabilization is a common mechanism by which mutations cause human diseases. In this study, machine learning approaches were developed for predicting human tissue-specific genes, protein sumoylation sites and protein stability changes upon single amino acid substitutions. Relevant biological features were selected for input vector encoding, …