Life Sciences Commons^™

Effects Of Transportation Hazards On Package Performance And Food Product Shelf Life, Kyle Dunno

All Dissertations

This research studied the effect of transportation hazards on food product shelf life and package performance. Studies were conducted to determine the effect of package headspace volume, product viscosity and storage temperature on package integrity. Finally, accelerated shelf life testing (ASLT) was utilized to determine how simulated transportation hazards affected the shelf life of a specific food product. Institutional retort pouches containing either water or 5% starch solution were filled with varying amounts of headspace volume to determine if package headspace volume could aid in package performance during simulated engineering tests for packaged products. Fixed displacement vibration testing and compression …

Investigating The Effects Of Biochemical And Biophysical Signals On Vascular Smooth Muscle Cell Differentiation, Ruikai Chen

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In blood vessel engineering, an optimal bioartifical scaffold can be characterized as a 3D tubular structure with high porosity for nutrient diffusion and enough mechanical strength to sustain in vivo dynamic environment. The luminal surface of the scaffold is supposed to have a continuous layer of endothelial cell that is ideally non-immunogenic and non-thrombogenic while the media layer of the construct is assigned for the ingrowth of vascular smooth muscle cell which can provide structural integrity and contractility. While reconstructing endothelial cell layer has been at the center of interest in most polymeric vascular replacements related research, growing VSMCs has …

Ecological, Physiological, And Molecular Characterization Of Annual Bluegrass (Poa Annua L.) Herbicide Resistance And Its Control On Golf Courses, Robert Cross

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Annual bluegrass (Poa annua L.) is one of the most pervasive, adaptable, and variable plant species in the world and is the most problematic winter annual weed in managed turfgrass. Its prolific seedhead production regardless of mowing height, clumping growth habit, and lack of tolerance to stress reduces turfgrass aesthetic quality and playability on golf courses. Its ability to germinate almost year-round influences cultural practices and herbicide use. Herbicides are an integral part of a weed control program for all weeds that invade a desirable turfgrass stand. However, inappropriate use of herbicides results in herbicide resistance issues. In recent years, …

Phylogenomics And Historical Biogeography Of The Gooseneck Barnacle Pollicipes Elegans, Sergio Andres Marchant Rojas

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This dissertation explores the systematics, biogeography, and genomics of the gooseneck barnacle Pollicipes elegans, a marine crustacean of the tropical Eastern Pacific. In Chapter 1, I provide a broad framework for my research by introducing and focusing on the long-­‐standing debate of the mechanisms behind the latitudinal gradient in species diversity, which provided the initial motivation for using Pollicipes elegans as a model system to study the mechanisms leading to genetic differentiation and speciation in tropical regions. In Chapter 2, I examine the genetic structure, infer patterns of connectivity across the warm tropical waters of the eastern Pacific, and reconstruct …

Genetic Dissection Of Neuromuscular Diseases Affecting Domestic Dogs, Caitlin Rinz

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The domestic dog, Canis familiaris, has a unique population structure that lends itself to the study of hereditary diseases. Purebred dogs populations are genetically isolated and as a result are affected by more than 400 naturally occurring diseases, many of which have human counterparts. In the last 15 years, dogs have emerged as a model for the study of human hereditary diseases, fueling the development of resources including a 7.6X coverage reference genome and single nucleotide polymorphism (SNP) genotyping arrays.

Congenital myasthenic syndrome (CMS) is a neuromuscular disorder of both humans and dogs in which transmission across the neuromuscular …

Specificity And Catalytic Mechanism Of Dna Glycosylases In Udg Superfamily, Bo Xia

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DNA can be damaged by several kinds of endogenous and exogenous reactive nitrogen species. Under nitosative stress, uracil (U), hypoxanthine (I), xanthine (X) and oxanine (O) are four major deaminated DNA bases derived from cytosine (C), adenine (A) and guanine (G) respectively. To repair this type of DNA damage, several different repair pathways are involved.

My dissertation work mainly focused on the uracil-DNA glycosylase (UDG) superfamily, which includes several groups of enzymes that recognize the damaged DNA bases and initiate the base excision repair (BER) pathway, one of the most important repair pathways to deal with deaminated DNA bases. Chapter …

Development And Application Of Scalable Two-Dimensional High Performance Liquid Chromatography For Aromatic Selective Separations Of Biologically Active Phytochemicals From Oplopanax Horridus, Gregory Jones

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The high demand for more efficient purification processes with increased automation and throughput pushes the development of more advanced preparative, pilot, and process scale HPLC instrumentation that is capable of achieving higher purities in a shorter amount of time than are currently achieved using one dimensional separations. A preparative scale 2D HPLC system was designed and reduced to practice in order to demonstrate the capacity for scalability of on-line comprehensive 2D HPLC separations of basic compounds from a challenging natural product extract of Oplopanax horridus. The methodology and instrumentation design herein permits direct method transfer from analytical to preparative scale …

Allosteric Regulation Of Bacterial And Fungal Xylulose 5-Phosphate/ Fructose 6-Phosphate Phosphoketolases (Xfps), Katie Glenn

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Acetate is excreted as a metabolic end product in many microbes. Acetate production has primarily been studied in bacteria and archaea but is known to occur in eukaryotic organisms as well. For example, acetate is one of the most abundant metabolites excreted by the fungal pathogen Cryptococcus neoformans during cryptococcosis suggesting that acetate production may be important during pathogenesis. One possible pathway for acetate production in C. neoformans involves the enzymes xylulose 5-phosphate/ fructose 6-phosphate phosphoketolase (Xfp), which can generate acetyl phosphate from either fructose 6-phosphate (F6P) or xylulose 5-phosphate (X5P), and acetate kinase (Ack), which can then convert acetyl …

Biology And Control Of The Bed Bug Cimex Lectularius L., Kevin Hinson

All Dissertations

After vanishing from the public eye for more than 50 years, bed bugs have resurged to become one of the most widely discussed and heavily researched insect pests in the westernized world. Our inability to prevent and successfully treat infestations has been the driving force behind this wave of research. I addressed gaps in our understanding of bed bugs by examining behavioral and life history characteristics, as well as insecticide application responses. I showed that natural-based products are generally ineffective against bed bugs, particularly when used as a residual treatment. I also found that bed bugs may be killed through …

Spatial Distribution And Genetic Variability Of Reniform And Lance Nematodes In Cotton Agroecosystems, Claudia Holguin

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Rotylenchulus reniformis (reniform nematode) and Hoplolaimus columbus (Columbia lance nematode) are two of the main plant-pathogenic nematode species affecting cotton production in the United States. For the selection and implementation of effective management practices it is important to understand distribution patterns and population genetic structure of these two nematodes in cotton agroecosystems. In a three-year field study, the spatial distribution of reniform nematode was characterized in two commercial fields in South Carolina to determine the effects of relations with soil texture and crop rotation on reniform nematode distribution (Chapter 1). Results of this project suggest that population densities of reniform …

The Avian Thrombocyte Is A Specialized Immune Cell, Farzana Ferdous

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Thrombocytes are the most abundant circulating cells next to red blood cells in avian blood. Avian thrombocytes are homologous in function to mammalian platelets. Avian thrombocytes and the mammalian platelet are widely recognized contributors to inflammatory responses upon stimulation with various microbial stimulants. However, some observed responses of the avian thrombocyte depart from a standardized model ascribed to innate cells. To help unravel the role of thrombocytes in innate immunity, and possibly adaptive immunity, first we examined the surface features of chicken thrombocytes. Chicken thrombocytes constitutively express transcripts for different Toll-like receptors (TLRs) that are crucial for the innate immune …

Evaluation Of A Mycorrhizal-Like Fungus, Piriformospora Indica, On Floriculture Crops, Allison Justice

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Piriformospora indica is a fungal endophyte, often called an arbuscular mycorrhizal-like fungus, that has been shown to provide benefits to plant symbionts by increasing nutrient uptake, biomass production, flower number, and disease resistance in a wide range of plant hosts. Research was carried out to investigate the ability of P. indica to improve plant production in floriculture crops. The first objective was to determine the optimal environmental conditions for growing P. indica in pure culture. Environmental conditions were optimized to produce the maximum chlamydospores for inoculum preparation (Chapter 1). These findings were used in the remaining chapters to prepare inocula …

South Atlantic Stream Fish Assemblages: Multi-Scale Structuring Factors, Trait Associations And Channelization, And Responses To Dam Removal, Cathy Marion

All Dissertations

South Atlantic coastal plain wadeable streams are unique and understudied freshwater environments that provide crucial habitats for a wide range of aquatic taxa. In Chapter 1, we investigated patterns in fish assemblages across South Carolina's coastal plain, and developed statistical models to identify the dominant multi-scale abiotic environmental factors that influence assemblage structure. Our analyses indicated the presence of four predominant fish assemblages that commonly occur in the coastal plain, which we termed the: 1) fluvial, 2) eastern mudminnow, 3) centrarchid, and 4) non-fluvial assemblages. Natural geographic gradients and instream habitat parameters associated with velocity, channel form, stream size, and …

Application Of Modern Statistical Tools To Solving Contemporary Economic Problems: Evaluation Of The Regional Agricultural Campaign Impact And The Usda Forecasting Efforts, Ran Xie

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The research is comprised with three studies to implement statistical tools for examining two economic issues: the impact of a regional agricultural campaign on participating restaurants and efforts of U.S. Department of Agriculture (USDA) forecasting reports in agricultural commodity markets. The first study examined how various components of the Certified South Carolina campaign are valued by participating restaurants. A choice experiment was conducted to estimate the average willingness to pay (WTP) for each campaign component using a mixed logit model. Three existing campaign components--Labeling, Multimedia Advertising, and the 'Fresh on the Menu' program were found to have a significant positive …

Biology, Ecology, And Control Of Doveweed (Murdannia Nudiflora [L.] Brenan), Jeffrey Atkinson

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Doveweed (Murdannia nudiflora [L.] Brenan) is a summer annual in the Southeastern United States with an expanding geographic range. The light green color and texture of doveweed is problematic for turfgrass managers as it contrasts with the color and texture of desirable turfgrasses. Limited research is available concerning the biology, ecology, and herbicide control options for doveweed. Therefore, experiments were conducted to improve the understanding of how environmental conditions effect doveweed germination, how cultural practices and environmental resource availability effect doveweed growth and development, to identify pre- and postemergence herbicides with efficacy for doveweed control, and to improve the understanding …

Evaluation Of The Functional Capabilities Of Fins And Limbs For Moving On Land: Insights Into The Invasion Of Land By Tetrapods, Sandy Kawano

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Transitions to novel habitats present different adaptive challenges, producing captivating examples of how functional innovations of the musculoskeletal system influence phenotypic divergence and adaptive radiations. One intriguing example is the transition from aquatic fishes to tetrapods. Recent technological advances and discoveries of critical fossils have catapulted our understanding on how fishes gave rise to terrestrial vertebrates. Considerable attention has been paid to legged locomotion on land, but given that the first tetrapods were aquatic, limbs did not evolve primarily for terrestriality. How, then, is the locomotor function of limbs different from fins? Extant amphibious fishes demonstrate that fins can be …

Use Of Macroinvertebrates In Bioassessment Of Land Use And Water Quality In Northern Mongolia, Oyunchuluun Yadamsuren

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Land-use practices in Mongolia lead to habitat degradation and consequently affect the structure and function of biological communities. There is no accepted bioassessment technique for determining the ecological consequences of habitat degradation on biological communities and water quality in Mongolia, such that a monitoring and management program suitable for Mongolia is sorely needed. Both a trait-based approach and the North American Rapid Bioassessment Protocol (RBP) metrics were tested with macroinvertebrates to determine the performance and applicability of these approaches for predicting general ecological responses of freshwater and terrestrial communities to habitat variation due to overgrazing and mining in northern Mongolian …

Influence Of Periostin On Bone Marrow-Derived Cell Contribution To Dermal Wound Repair, Suzanne Parks

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Originally thought to function only as a scaffold, the extracellular matrix (ECM) is now understood to provide signals that regulate all aspects of cellular phenotype. Matricellular proteins are a subset of ECM-related molecules defined by their ability to modulate interactions between cells and the ECM. Periostin was recently classified as a matricellular protein based on its expression and function during development and wound repair. Periostin has been shown to influence cell behavior and collagen fibrillogenesis in several tissue types. In this study, we examined how periostin expression influences fibrocyte behavior after dermal injury using periostin null (Pstn -/-) and wild-type …

Impact And Management Of Megacopta Cribraria (Hemiptera: Plataspidae), Nicholas Seiter

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Megacopta cribraria (F.) (Hemiptera: Plataspidae), known informally as the kudzu bug or bean plataspid, was found in Georgia in 2009 and has since spread rapidly throughout the southeastern United States. A known feeder on soybean, Glycine max (L.) Merrill, in its native Asian range, M. cribraria has been commonly encountered in soybean fields in the southeastern United States since its first detection in the crop in Georgia and South Carolina during 2010. In addition, its overwintering behavior sometimes results in nuisance infestations in homes. The primary objectives of this research were to determine the potential impacts of M. cribraria on …

The Effects Of Indirubin-3’-(2,3 Dihydroxypropyl)-Oximether (E804) On Inflammation Profile In Macrophages, Amy Lauren Anderson

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Indirubin is a deep-red bis-indole isomer of indigo blue, both of which are biologically active ingredients in Danggui Longhui Wan, an ancient Chinese herbal tea mixture used to treat neoplasia and chronic inflammation, and to enhance detoxification of xenobiotics. Multiple indirubin derivatives have been synthesized and shown to inhibit cyclin-dependent kinases (CDKs) and glycogen-synthase kinase (GSK-3β) with varying degrees of potency. Several indirubins are also aryl hydrocarbon receptor (AhR) agonists, with AhR-associated activities covering a wide range of potencies, depending on structure-activity-relationships (SAR). In this study, the effects on indirubin-3’-(2,3 dihydroxypropyl)-oximether (E804), a novel indirubin derivative with potent effects on …

Range Collapse, Genetic Differentiation, And Climate Change: An Ecological History Of The Diana Fritillary, Speyeria Diana And Projections For Its Future, Carrie Wells

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The geographic ranges of most plant and animal species are tied closely to climatic factors, including temperature, precipitation, and soil moisture. For this reason, recent changes in the global climate due to human activities are predicted to have profound effects on natural populations, communities and ecosystems over a relatively short period of time. Combined effects from global warming and other anthropogenic activities such as land-use changes, pollution, and habitat loss/fragmentation, are altering species' distributions faster than they can be documented. Recent climate change has also been shown to alter species' breeding behaviors and alter the synchrony and timing of species' …

Socioeconomic Indicators Of Family Forest Owner Use Of Federal Income Tax Provisions, John Hatcher

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Family forest owners control a majority of the South's forest land and nearly half of its growing stock. These owners are a diverse group with widely varied objectives for ownership and management. Many family forest owners manage their holdings for timber production objectives and thus, are concerned with issues such as reforestation incentives and tax treatment of timber revenues. Their actual knowledge of the tax aspects of timber management varies, with some owners unaware of the federal income tax provisions that apply to timber. This study uses econometric techniques to establish socioeconomic predictors of family forest owner use of seven …

Range Limits, Range Shifts, And Lower Thermal Tolerance In The Tropical Barnacle Megabalanus Coccopoma, Samuel Crickenberger

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Climate change and species introductions are leading to shifts in marine species' geographic distributions. However, few studies have examined range limits and range shifts in tropical marine species. The barnacle Megabalanus coccopoma is native to shorelines from Baja California to Peru and has been introduced to a number of locations worldwide including the Atlantic US SE coast, where its current introduced range extends from Ft. Pierce, FL to Cape Hatteras, NC with seasonal populations as far north as Kitty Hawk, NC. In order to understand the potential poleward range limit of M. coccopoma in the US SE under modern day …