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Full-Text Articles in Life Sciences

Distribution, Ecology, And Trophic Relationships Of A Colonial Waterbird: The Double-Crested Cormorant, Kate Sheehan Dec 2013

Distribution, Ecology, And Trophic Relationships Of A Colonial Waterbird: The Double-Crested Cormorant, Kate Sheehan

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The realized distribution of an organism is dependent on the environmental characteristics of the landscape, biological interactions within the communities in which it lives, and geographic barriers to dispersal. Changes in habitat can influence landscape characteristics, and consequently, the distribution of organisms within the landscape. The Double-crested Cormorant ( Phalacrocorax auritus ) is a piscivorous waterbird implicated in human-wildlife conflicts at aquaculture facilities and natural aquatic systems where they compete for resources (fish) with anglers and commercial fishing guides. Impacts of P. auritus on aquatic systems result from their consumption of fish stocks and their contamination of water and soil with guano ...


Prolactin And Isplatin Combination Treatment Inhibit Tumorspheres Formation And Tumor Growth In Mice, Eric Hingleung Lee Dec 2013

Prolactin And Isplatin Combination Treatment Inhibit Tumorspheres Formation And Tumor Growth In Mice, Eric Hingleung Lee

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Cancer stem cells (CSCs) are defined as a small population of tumor initiating cells that are responsible for the initiation, development, progression, and recurrence of cancer. The chemo and radiation resistance of CSCs remains one of the major obstacles in conventional anti-cancer therapies. One of the reasons that conventional chemotherapeutics are not effective in targeting CSCs is that CSCs are usually in a non-proliferative or dormant state. In this perspective, targeting CSCs by inducing its proliferation and differentiation and simultaneously applying chemotherapeutics may be an alternative approach. The current study investigates the effect of prolactin (PRL), a hormone intimately involved ...


Studies Of Molecular Mechanisms Of Cranberry Mediated Healthspan Promotion In Caenorhabditis Elegans, Sujay Guha Dec 2013

Studies Of Molecular Mechanisms Of Cranberry Mediated Healthspan Promotion In Caenorhabditis Elegans, Sujay Guha

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Extensive studies have demonstrated the potent ability of many nutraceuticals to alleviate the symptoms of aging and stress. We found that cranberry extract (CBE) supplementation at an optimum concentration could prolong Caenorhabditis elegans (C. elegans) lifespan in a manner of daf-16 and osr-1 dependence. Considering that aging is a progressive degeneration of physiological functions, it is intriguing to know whether CBE consumption may delay the age-related degenerative changes in animals. Thus, we examined the effect of CBE consumption on healthspan in C. elegans populations with different ages and age-related disorders. Our results suggest that long-term CBE supplementation leads to a ...


Three Essays Evaluating Health Impacts Of The National School Lunch Program, Janet Peckham Dec 2013

Three Essays Evaluating Health Impacts Of The National School Lunch Program, Janet Peckham

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This research focuses on the health impacts of participation in the National School Lunch Program, a program providing free and reduced-cost lunches for income-eligible students and minimally subsidizing lunches for income-ineligible students. In the past decade, increasing incidence of childhood obesity, particularly among low-income individuals has drawn scrutiny over the NSLP's role in the health of student-aged children.

The first chapter introduces the reader to the NSLP, providing a history of the program since its inception at the turn of the 20th century and addressing current issues in the economic literature regarding health impacts of program participation. The second ...


Validation Of Thermal Destruction Of Pathogenic Bacteria In Rendered Animal Products, Mary Hayes Dec 2013

Validation Of Thermal Destruction Of Pathogenic Bacteria In Rendered Animal Products, Mary Hayes

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This study tested enumeration techniques for high fat food matrices and determined thermal death times in rendering animal products. Standard Class O phosphate/magnesium chloride dilution buffer series (Dilution Series A) and a modified (pre-warmed to 32oC) lecithin phosphate dilution buffer series (Dilution Series B) were used to enumerate a Salmonella cocktail from both poultry and beef rendering materials. Results of this study indicate use of a modified lecithin buffer did not improve Salmonella enumeration accuracy from rendering materials. Instead, the results suggested use of xylose lysine deoxycholate agar (XLD) with either buffer system accurately enumerated Salmonella from rendering materials ...


Factors Influencing The Distribution And Structure Of Tropical Vascular Epiphyte Communities At Multiple Scales, Carrie Woods Aug 2013

Factors Influencing The Distribution And Structure Of Tropical Vascular Epiphyte Communities At Multiple Scales, Carrie Woods

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Understanding the factors that determine species distributions is a central question in ecology. Niche-based theories stress the importance of environmental heterogeneity in influencing species distributions while neutral-based theories emphasize the effects of dispersal limitation. The relative importance of these factors in influencing species distributions may depend on spatial scale - deterministic factors may be more important at small spatial scales where fine-scale habitat factors become more relevant and stochastic factors may be more important at larger spatial scales where dispersal limitation becomes more relevant. I examined the influence of deterministic and stochastic factors on the distribution and structure of vascular epiphyte ...


The Effects Of Altering Incubation Temperature On Broiler Chick Hatchability, Chick Quality, Sex Ratio, And Subsequent Performance Under Field Conditions, Abubaker Elmehdawi Aug 2013

The Effects Of Altering Incubation Temperature On Broiler Chick Hatchability, Chick Quality, Sex Ratio, And Subsequent Performance Under Field Conditions, Abubaker Elmehdawi

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The aim of this dissertation was to investigate the effects of manipulating the incubation temperature during late broiler embryogenesis on hatchability, chick quality, secondary sex ratio, and grow out performance under field conditions. Four experiments were conducted at a commercial hatchery and two setters of 42,240 eggs each were used; one served as control and the other as test with the same physical environment as the control except that thermal stimulation of 0.5o C and 1o C above the optimal incubation temperature were used, in the first two experiments and last two experiments respectively, for 2 h/d ...


Role Of Phosphoinositide-Based Signaling In Virulence In Entamoeba Histolytica, Amrita Koushik Aug 2013

Role Of Phosphoinositide-Based Signaling In Virulence In Entamoeba Histolytica, Amrita Koushik

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Entamoeba histolytica is an intestinal protozoan parasite and is the causative agent of amoebiasis. Upon entering the human host, cellular processes such as adhesion, phagocytosis, motility and secretion play a vital role in its propagation and pathogenicity. In other systems, each of these cellular processes is preceded by activation of signal transduction pathways, which often involve membrane phosphoinositides such as phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). Little is known about phosphoinositide signaling in E. histolytica pathogenicity. In this study, we demonstrated that PI(4,5)P2 is localized to cholesterol-rich microdomains, lipid rafts, of the E. histolytica ...


Ecology And Management Of Stink Bugs (Hemiptera: Pentatomidae) In Southeastern Farmscapes, Grant Pilkay Aug 2013

Ecology And Management Of Stink Bugs (Hemiptera: Pentatomidae) In Southeastern Farmscapes, Grant Pilkay

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A three-year study (2009-2011) was conducted to examine the spatial and temporal dynamics of stink bugs in three commercial farmscapes in South Carolina and Georgia. Crops included wheat, Triticum aestivum (L.), corn, Zea mays (L.), soybean, Glycine max (L.), cotton, Gossypium hirsutum (L.), and peanuts, Arachis hypogaea (L.). Farmscapes were sampled weekly using whole-plant examinations for corn, with all other crops sampled using sweep nets. The predominant pest species of phytophagous stink bugs were the brown stink bug, Euschistus servus (Say), the green stink bug, Chinavia hilaris (Say), and the southern green stink bug, Nezara viridula (L.). Chi-square tests indicated ...


Comparing Mechanical Mastication, Herbicide Application, And Prescribed Fire Within An Established Longleaf Pine (Pinus Palustris Mill.) Ecosystem, Brett Moule Aug 2013

Comparing Mechanical Mastication, Herbicide Application, And Prescribed Fire Within An Established Longleaf Pine (Pinus Palustris Mill.) Ecosystem, Brett Moule

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Longleaf pine (Pinus palustris Mill.) forests once dominated the landscape throughout the Southeast and much of its success could be attributed to ecological disturbances such as fire. However, the use of fire as a management tool may be at risk due to a growing human population, negative impacts resulting from smoke production, and the imposition of restrictive federal and state laws, policies, and standards. This study was designed to determine whether alternative silviculture treatments such as herbicide or mechanical mastication can be used as surrogates to prescribed fire. We applied three commonly used silviculture treatments (prescribed burning, mechanical mastication, and ...


Gap Junctions: Regulators Of Cellular Immunity And Parasite Manipulation In The Remarkable Tripartite Relationship Involving Insects And Genome-Integrated Polydnaviruses, Daniel Hasegawa Aug 2013

Gap Junctions: Regulators Of Cellular Immunity And Parasite Manipulation In The Remarkable Tripartite Relationship Involving Insects And Genome-Integrated Polydnaviruses, Daniel Hasegawa

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Communication means everything. From vocalization to the firing of a neuron, coordination through the exchange of signals is essential to the survival of all living things. At the cellular level, communication is accomplished through the use of gap junction channels. Gap junctions are found in virtually all multicellular animals, where they play critical roles in developmental, physiological, metabolic, and even structural processes. From the maintenance of heart rhythms in humans, to the coordination of tissue regeneration in flatworms, and to the processing of visual stimuli in flies, the roles for gap junctions are diverse. However, how this diversity is accomplished ...


Antibacterial Effects Of Proteases On Different Strains Of Escherichia Coli And Listeria Monocytogenes, Hanan Eshamah Aug 2013

Antibacterial Effects Of Proteases On Different Strains Of Escherichia Coli And Listeria Monocytogenes, Hanan Eshamah

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Escherichia coli O157:H7 and Listeria monocytogenes are pathogens that have received special attention by federal agencies, food safety researchers and food industries due to their economic and human health impact. To reduce the presence of these pathogens, alternative interventions have been studied. However, increasing consumer's demand for natural ingredients has made the investigations of effectiveness of natural antimicrobials necessary. In this study, in vitro antimicrobial activity of bromelain and papain against E. coli JM109 and L. monocytogenes was investigated. Furthermore, actinidin and papain were evaluated to reduce populations of L. monocytogenes strain and three mixed strains of E ...


Influences Of Riparian Land-Uses On Habitat Use And Interspecific Competition Of Stream-Dwelling Salamanders: Evidence From Blue Ridge & Piedmont, Thilina Surasinghe Aug 2013

Influences Of Riparian Land-Uses On Habitat Use And Interspecific Competition Of Stream-Dwelling Salamanders: Evidence From Blue Ridge & Piedmont, Thilina Surasinghe

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Human-induced disturbances can result in persistent influences on ecosystems, including habitat loss and biogeographical changes. Global amphibian decline, a consequence of habitat degradation, is among prime conservation concerns. To better understand causes of the amphibian crisis, investigations a multiple levels of biological organization - behavior, communities, and landscapes - is imperative. I investigated the responses of stream-associated Plethdontid salamanders of the Blue Ridge and Piedmont of the Southeastern US to historical and current land uses in the riparian zone and watershed to determine, (1) change in the community structure and mechanisms driving the change and uses operating at different spatial-temporal scales; (2 ...


Biochemical Investigation Into Initiation Of Fatty Acid Synthesis In The African Trypanosomes, Sunayan Ray Aug 2013

Biochemical Investigation Into Initiation Of Fatty Acid Synthesis In The African Trypanosomes, Sunayan Ray

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My doctoral studies focused on studying FA metabolism in the deadly protozoan parasite T. brucei. In my dissertation, I will be addressing various aspects of the regulation of TbACC, which catalyzes the first committed step in FA synthesis. In the second chapter, I hypothesized that TbACC is regulated in response to environmental lipids. I examined changes in TbACC RNA, protein, and activity in response to different levels of environmental lipids in both BF and PF cells. I also delineated the mechanisms by which TbACC expression and activity is regulated by phosphorylation in response to altered lipid environments. In the third ...


Development And Testing The Validity And Reliability Of Items And Scales To Assess Physical Activity Behavior Of Adults In The Expanded Food And Nutrition Education Program, Tarana Khan Aug 2013

Development And Testing The Validity And Reliability Of Items And Scales To Assess Physical Activity Behavior Of Adults In The Expanded Food And Nutrition Education Program, Tarana Khan

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Given the rising prevalence of obesity and other chronic diseases in the United States, the Expanded Food and Nutrition Education Program (EFNEP) includes physical activity as a core educational component along with diet quality, food safety, food resource management and food security. According to the Dietary Guidelines for Americans, research supports that participation in regular physical activity helps people maintain a healthy weight and prevent excess weight gain. When combined with reduced calorie intake, physical activity may aid weight loss and the maintenance of weight loss.
Two evaluation instruments are used in EFNEP nationwide. Nutritional intake is measured by a ...


Effects Of Varying Spring Hollow Tine Aerification Size And Timing On Bentgrass Greens, Lewis Hubbard Jr Aug 2013

Effects Of Varying Spring Hollow Tine Aerification Size And Timing On Bentgrass Greens, Lewis Hubbard Jr

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The desire to maintain optimal turfgrass and surface properties often leads turfgrass managers to minimize impact from cultural practices like hollow tine aerification (HTA). Comprehensive research is essential to developing aerification programs which allow optimal use of turfgrass surfaces without sacrificing overall turf health.
A two-year field experiment was conducted on a 14-year-old U.S. Golf Association (USGA)-specified Crenshaw creeping bentgrass [Agrostis stolonifera L. var palustris (Huds.)] research putting green in Clemson, SC, to evaluate the effects of varying spring HTA size and timing on turfgrass, surface, organic matter (OM), and soil properties.
Spring HTA treatments included 1.2-cm ...


Behavior And Control Of The Bed Bug, Cimex Lectularius L. (Hemiptera: Cimicidae), Margaret Lehnert Aug 2013

Behavior And Control Of The Bed Bug, Cimex Lectularius L. (Hemiptera: Cimicidae), Margaret Lehnert

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The recent resurgence of bed bugs has led to an explosion of bed bug research influenced by the applied needs of pest management professionals. I assessed the needs of pest management professionals who deal with bed bugs in South Carolina. Bed bugs were reported in 28 of 46 counties in South Carolina. Previous samples of bed bug populations have displayed a 1:1 sex-ratio suggesting females do not use aggregations and harborages to hide from males and traumatic insemination, which can be harmful to females. Aggregations are biased in composition, suggesting that females are able to hide from males within ...


Functionalized Nanomaterials And Their Biological Applications, Pallavi Vedantam Aug 2013

Functionalized Nanomaterials And Their Biological Applications, Pallavi Vedantam

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Bionanomaterials have been used in drug delivery, cancer therapy and biodiagnosis of pathogens based on their size and surface functionalization. In this present work, different kinds of nanoparticles (NPs), their cellular interactions, cytotoxicity profiles, and finally role of gold nanoparticles (GNPs) in biodetection of E. coli was investigated.
Firstly, cytotoxicity profiles of commercial, laser ablation, and green synthetic NPs were studied. Induction of apoptosis in cancer cells was found to be size dependent. The plain 80 nm GNPs and AgNPs enhanced toxic effects in cancer cells when compared to 20 nm ones. Apoptotic profiles of ALB- or FBS-coated NPs were ...


A Novel Gain Of Function Of The Irx1 And Irx2 Genes Disrupts Axis Elongation In The Araucana Rumpless Chicken, Nowlan Freese Aug 2013

A Novel Gain Of Function Of The Irx1 And Irx2 Genes Disrupts Axis Elongation In The Araucana Rumpless Chicken, Nowlan Freese

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Caudal dysplasia describes a range of developmental disorders that affect normal development of the lumbar spinal column, sacrum and pelvis. An important goal of the congenital malformation field is to identify the genetic mechanisms leading to caudal deformities.
To identify the genetic cause(s) and subsequent molecular mechanisms I turned to an animal model, the rumpless Araucana chicken breed. Araucana fail to form vertebrae beyond the level of the hips. I performed a genome wide association study to identify candidate genomic regions associated with the rumpless phenotype, compared to tailed Araucana. A candidate region of chromosome 2 containing just two ...


Conserved Noncoding Sequences Regulate Steady-State Mrna Levels In Arabidopsis Thaliana, Jacob Spangler May 2013

Conserved Noncoding Sequences Regulate Steady-State Mrna Levels In Arabidopsis Thaliana, Jacob Spangler

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Arabidopsis thaliana has undergone three whole genome duplications within its ancestry, and these events have dramatically affected its gene complement. Of the most recent whole genome duplication events (&alpha event), there remain 11,452 conserved noncoding sequences (CNSs) that have been retained proximal to &alpha duplicate gene pairs. As functional DNA elements are expected to diverge in sequence at a slower rate than nonfunctional DNA elements, the retained CNSs likely encode gene regulatory function. Within this dissertation I provide evidence for the regulatory role of CNSs within Arabidopsis thaliana. Using a collection of over 5,000 microarray RNA expression profiling ...


Predicting Complex Phenotype-Genotype Relationships In Grasses: A Systems Genetics Approach, Stephen Ficklin May 2013

Predicting Complex Phenotype-Genotype Relationships In Grasses: A Systems Genetics Approach, Stephen Ficklin

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It is becoming increasingly urgent to identify and understand the mechanisms underlying complex traits. Expected increases in the human population coupled with climate change make this especially urgent for grasses in the Poaceae family because these serve as major staples of the human and livestock diets worldwide. In particular, Oryza sativa (rice), Triticum spp. (wheat), Zea mays (maize), and Saccharum spp. (sugarcane) are among the top agricultural commodities. Molecular marker tools such as linkage-based Quantitative Trait Loci (QTL) mapping, Genome-Wide Association Studies (GWAS), Multiple Marker Assisted Selection (MMAS), and Genome Selection (GS) techniques offer promise for understanding the mechanisms behind ...


Integrating Biomechanics And Cell Physiology To Understanding Ivd Nutrition And Cell Homeostasis, Yongren Wu May 2013

Integrating Biomechanics And Cell Physiology To Understanding Ivd Nutrition And Cell Homeostasis, Yongren Wu

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Back pain associated with degeneration of the intervertebral disc (IVD) is a major public health problem in Western industrialized societies. Degeneration of the IVD changes the osmotic and nutrient environment in the extracellular matrix (ECM) which affects cell behaviors, including: cell proliferation, cell energy metabolism, and matrix synthesis. In addition, a thin layer of hyaline cartilaginous end-plate (CEP) at the superior/inferior disc-vertebral interface was found to play an important role in nutrient supply as well as load distribution in the IVD. Therefore, our general hypothesis is that the CEP regulates the ECM osmotic and nutrient environment which further affects ...


Early Skeletal Morphogenesis: The Role Of Pharyngeal Endoderm Derived Signaling During Specification Of Craniofacial Skeleton And Interplay Of Mechanical Forces And Molecular Signaling During Skeletal Condensation, Poulomi Ray May 2013

Early Skeletal Morphogenesis: The Role Of Pharyngeal Endoderm Derived Signaling During Specification Of Craniofacial Skeleton And Interplay Of Mechanical Forces And Molecular Signaling During Skeletal Condensation, Poulomi Ray

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This study examines the fundamental principles governing the early
stages of skeletal morphogenesis. I specifically investigate the specification of mesenchymal progenitor cells to a skeletal fate. Using explant culture system, I determine that the pharyngeal endoderm was sufficient, but not necessary for specifying pre-chondrogenic identity. FGF signaling is both sufficient and required for specification of Sox9 expression and specification of prechondrogenic identity, as demonstrated by the addition of recombinant FGF protein or the FGF receptor inhibitor (SU5402) to explanted tissue, respectively. However, FGF signaling cannot maintain Sox9 expression or initiate the chondrogenic program as indicated by the absence of Col2a1 ...


Transforming The South Carolina Botanical Garden, Amy Blackwell May 2013

Transforming The South Carolina Botanical Garden, Amy Blackwell

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This dissertation addresses the question of how to transform a small to mid-sized public garden into a botanical garden capable of making a significant contribution to science. Botanical gardens have certain features that distinguish them from pleasure gardens and public parks. These include a scientific basis for collections, an emphasis on recording data on the plants in the collection, exchanging plant materials and data with other botanical gardens, and providing educational information to visitors. Gardens often have several missions, including conservation of rare and endangered species, botanical and ecological research, and involving the public through citizen science. I describe my ...


Correlation Of Physicochemical Properties Of Chondroitin Sulfate To Its In-Vitro Absorption And Anti-Inflammatory Activity, Lahari Surapaneni May 2013

Correlation Of Physicochemical Properties Of Chondroitin Sulfate To Its In-Vitro Absorption And Anti-Inflammatory Activity, Lahari Surapaneni

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The purpose of this study was to investigate if the molecular weight and degree of sulfation of chondroitin sulfate (CS) has an impact on its in vitro absorption and anti-inflammatory activity.
For absorption studies, Caco-2 cells were incubated with eight CS samples of differing molecular weights (7 kDa - 35 kDa). The amount of CS transported into the basolateral side of the Caco-2 monolayer was quantitatively determined to calculate the permeability coefficients (Peff). The permeability coefficients of the eight different CS samples across Caco-2 cell monolayers were assessed. For anti-inflammatory studies, RAW 264.7 murine macrophage cells were pre incubated with ...


Analysis Of The Interaction Of Francisella Tularensis Lvs And Legionella Pneumophila Biofilms With Components Of The Aquatic Environment, Uma Mahajan May 2013

Analysis Of The Interaction Of Francisella Tularensis Lvs And Legionella Pneumophila Biofilms With Components Of The Aquatic Environment, Uma Mahajan

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Biofilms are complex communities of organisms enclosed in a matrix (EPS) composed of polysaccharides, proteins and DNA. Biofilms are the base of the aquatic ecosystem and interact with the biotic as well as the abiotic components in the environment. Biofilms interact with biotic components of the environment such as protozoa and aquatic invertebrates. In this project, the biotic interactions of Francisella tularensis LVS biofilms are studied in relation to the mosquito larvae of Culex quinquefasciatus. F. tularensis is the causative agent of tularemia and is transmitted by ticks, deer flies, and mosquitoes. Mosquitoes are believed to play a role in ...