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Full-Text Articles in Life Sciences

Characterization Of The Role Of Fro6 In Metal Homeostasis In Arabidopsis Thaliana, Margo Ellen Maynes Jan 2013

Characterization Of The Role Of Fro6 In Metal Homeostasis In Arabidopsis Thaliana, Margo Ellen Maynes

Theses and Dissertations

Iron deficiency is the most common human nutritional disorder in the world today, affecting approximately 2 billon people worldwide, almost a third of the world's population. For most of the world's population, plant foods serve as the major source of dietary iron. One approach that may contribute towards the solution of iron deficiency is the development of crop plants that contain higher levels of bioavailable iron. This project focuses on FRO6, a ferric chelate reductase in Arabidopsis thaliana that is thought to reduce apoplastic iron for transport across the plasma membrane in leaf cells. We hypothesize therefore that FRO6 controls …


The Role Of Host-Tumor Interactions In Liver Metastasis Of Colorectal Cancer, Yu Zhang Jan 2013

The Role Of Host-Tumor Interactions In Liver Metastasis Of Colorectal Cancer, Yu Zhang

Theses and Dissertations

Colon cancer is the third most frequent cancer and the second leading cause of cancer deaths in the United States. Liver metastasis is the major cause of death in colon cancer. Successful metastases depend on productive collaborations between tumor cells and host-derived cells in the tumor microenvironment, target organ environments, and cells in the hematopoietic compartment.

To identify the host-tumor interactions promoting liver metastasis and their molecular and cellular mediators, an orthotopic mouse model of liver metastasis of colon cancer was established that recapitulates all stages of tumor growth and metastasis. A highly metastatic mouse carcinoma cell line CT26-FL3 was …


The Effect Of Thymidylate Synthase Inhibitors On Bone Marrow Derived Cells In The Intestinal Tumor Microenvironment, Grishma Acharya Jan 2013

The Effect Of Thymidylate Synthase Inhibitors On Bone Marrow Derived Cells In The Intestinal Tumor Microenvironment, Grishma Acharya

Theses and Dissertations

Tumors have come to be known as independently functioning complex organs consisting of cancer cells coexisting with a heterogeneous mixture of host-derived non-neoplastic cells that form the tumor stroma. Tumor survival, progression, and metastasis depend on multiple close interactions between the cancer cells and the tumor stromal cells. These tumor stromal cells are mainly bone marrow derived cells (BMDCs) that are recruited to the primary tumor and sites of metastasis by a variety of signals secreted by the cancer cells. Because of the close interaction between the tumor and the tumor stroma, we propose that tumor stromal cells play an …


The Effects Of Rainfall-Runoff On Particulate Organic Carbon Cycling In Salt Marshes, Si Chen Jan 2013

The Effects Of Rainfall-Runoff On Particulate Organic Carbon Cycling In Salt Marshes, Si Chen

Theses and Dissertations

Low tide rainfall-runoff processes have been proposed as a kind of coastal ocean "hot moment" capable of transporting disproportionately large amounts of material from the salt marsh surface to the water column. However, the resulting organic matter cycling has not been well characterized and the cumulative effects of recurring short-term low tide rainfall events are not known, especially in the context of outwelling. The purpose of this Ph.D. research is to quantitatively evaluate the effects of low tide rainfall on particulate organic carbon (POC) cycling in a South Carolina salt marsh.

This dissertation is comprised of four parts. First, a …


The Association Of Physical Fitness With Psychological Health Outcomes In Soldiers During Army Basic Combat Training, Shannon K. Crowley Jan 2013

The Association Of Physical Fitness With Psychological Health Outcomes In Soldiers During Army Basic Combat Training, Shannon K. Crowley

Theses and Dissertations

Despite the current need for investigation of factors involved with soldiers' resilience to stressors in the Basic Combat Training (BCT) environment, and evidence in civilian populations that physical training is associated with psychological benefits, little is known about the relationship between physical fitness and psychological adjustment during BCT. Study one of this dissertation involved an extensive literature review of factors related to the relationship between physical fitness and psychological adjustment of soldiers during BCT. Using qualitative focus group methods, study two assessed soldiers' perceptions about their sleep, and consequences of sleep disruption during BCT at Fort Jackson in Columbia, SC. …


Measurement And Three-Dimensional Modeling Of Hydrodynamic Processes In The Inner Shelf And Surf Zone, Nirnimesh Kumar Jan 2013

Measurement And Three-Dimensional Modeling Of Hydrodynamic Processes In The Inner Shelf And Surf Zone, Nirnimesh Kumar

Theses and Dissertations

Wind stress and surface gravity waves play an important role in creating and modifying flows on the shelf. The importance of surface waves increases in shallow waters especially within the inner shelf and the surf zone. Understanding the generation and maintenance mechanisms of these flow patterns is a requirement for a number of environmental and ecological processes including the transport and fate of sediment, pollutants, buoyant river discharge and anthropogenic material introduced to the coastal zone. This dissertation examines inner shelf and surf zone circulation patterns through: (a) the development and validation of appropriate techniques to incorporate the effect of …


The Effect Of Cancer Cachexia Severity And Eccentric Muscle Contractions On Selected Myofiber Metabolic Properties In Mouse Skeletal Muscle, Joshua Earl Mangum Jan 2013

The Effect Of Cancer Cachexia Severity And Eccentric Muscle Contractions On Selected Myofiber Metabolic Properties In Mouse Skeletal Muscle, Joshua Earl Mangum

Theses and Dissertations

Cancer cachexia is a complex syndrome that induces skeletal muscle wasting and dysregulation of skeletal muscle metabolism. Alterations in area of myofibers and myofiber metabolic properties can significantly impact the function of skeletal muscle. The purpose of this study was to examine the effect of cachexia severity and resistance exercise training on frequency and area of selected myofiber metabolic characteristics during cachexia-induced myofiber atrophy. Male ApcMin/+ (Min) mice were studied during the progression of cachexia (16-20 weeks of age) and stratified into groups based on the severity of cachexia. For the second study, male Min mice performed resistance exercise (RE) …


Tidal Variability Of Waves And Currents On A Caribbean Barrier Reef, Chelsea Wegner Jan 2013

Tidal Variability Of Waves And Currents On A Caribbean Barrier Reef, Chelsea Wegner

Theses and Dissertations

The modern framework of Caribbean coral reefs is a product of resilient structures that have survived extreme variations in sea level for the past 18,000 years. However, the added influences of anthropogenic pressures, including ocean acidification, overfishing, pollution and bleaching make the future response to sea level rise uncertain. Carbonate production in the Caribbean is no longer at these historic rates and reefs may not be able to keep pace with the projected increases in sea level. This could have dramatic impacts on the hydrodynamics in coral reef environments, as reef morphology strongly influences these processes. Coral reefs are regarded …


Trophic Response To Polycyclic Aromatic Hydrocarbons And Copper In Tidal Flats Of North Inlet, South Carolina, Leslie Lynn Muggelberg Jan 2013

Trophic Response To Polycyclic Aromatic Hydrocarbons And Copper In Tidal Flats Of North Inlet, South Carolina, Leslie Lynn Muggelberg

Theses and Dissertations

The trophic link between benthic microalgae (BMA) and fiddler crabs is critical for the ecosystem functioning of estuaries and alterations in this linkage by anthropogenic activities could have cascading impacts on food webs and biogeochemical cycling in these sensitive habitats. Singular and interactive effects of two common pollutants in aquatic ecosystems, polycyclic aromatic hydrocarbons (PAHs) and copper (Cu), were investigated by exposing field collected sediment communities to the contaminants and measuring changes in BMA biomass and community composition in a bioassay design. The consequential impacts on the food web were then explored by examining the effects of PAHs and copper …


Differential Gene Expression Patterns In Hpv-Positive And Hpv-Negative Oropharyngeal Carcinomas, Swati Tomar Jan 2013

Differential Gene Expression Patterns In Hpv-Positive And Hpv-Negative Oropharyngeal Carcinomas, Swati Tomar

Theses and Dissertations

Head and neck (HN) cancer is the fifth most prevalent malignancy worldwide with 90% of them categorized as squamous cell carcinomas (SCC). Carcinomas of the oropharynx, pharynx and the oral cavity, comprise a subset of HNSCC and are referred to as oropharyngeal squamous cell carcinomas (OPSCC). Up to 60% of OPSCC and 25% of HNSCC are positive for high-risk human papillomavirus (HR-HPV), primarily HPV16. HPV positive and HPV negative OPSCC’s are molecularly and biologically distinct with differences in risk factors, age of presentation and clinical behavior. The precise molecular signatures of each have been well studied with respect to gene …


The Metabolic Transitions Regulated By The Estrogen-Related Receptor (Err) In Drosophila Melanogaster, Yan Li Jan 2013

The Metabolic Transitions Regulated By The Estrogen-Related Receptor (Err) In Drosophila Melanogaster, Yan Li

Theses and Dissertations

In multicellular organism, bioenergetic metabolism is strictly regulated toward efficient generation of ATP. However, in certain situations, such as in limiting oxygen or in the rapidly proliferating system like growing juvenile or cancer cells, organisms apply the metabolic strategy that favors the production of biomass (e.g., nucleotides, amino acids, and lipids) over efficiency of ATP generation. The conserved estrogen-related receptors (ERRs) are master regulators in controlling metabolic homeostasis, and good candidates for mediating the metabolic transition induced by hypoxia and development. First, we investigate how dERR influences hypoxic adaptation in Drosophila melanogaster. We find that dERR is required for a …


Calcium/Calmodulin-Dependent Protein Kinase Ii Beta (Camkiiβ): A Regulator Of Oligodendrocyte Maturation And Myelination, Christopher Waggener Jan 2013

Calcium/Calmodulin-Dependent Protein Kinase Ii Beta (Camkiiβ): A Regulator Of Oligodendrocyte Maturation And Myelination, Christopher Waggener

Theses and Dissertations

Oligodendrocytes are cells located in the central nervous system (CNS) that are responsible for the production of the lipid rich membrane, myelin. Myelin and the process of making and wrapping myelin around an axon (also known as myelination) are critical for normal development since they ensure proper signal conduction in the vertebrate CNS. The loss or damage of this myelin, which is typically associated with the demyelinating disease multiple sclerosis (MS), is associated with improper axonal protection along with disrupted nerve signaling which can lead to a variety of different debilitating phenotypic responses. It has been shown that there are …


Hormone Epimers Regulate Er Stress And Core Regulatory Genes: Network Analysis With Applications To Glioma And Chronic Pressure Ulcers, Thomas L. Shaak Jan 2013

Hormone Epimers Regulate Er Stress And Core Regulatory Genes: Network Analysis With Applications To Glioma And Chronic Pressure Ulcers, Thomas L. Shaak

Theses and Dissertations

DHEA has been determined to have medically significant activity and is the parent compound to the more active metabolites; 17α-AED, 17β-AED and 17β-AET, which exhibit strong biological activity that has been attributed to androgenic, estrogenic or anti-glucocorticoid activity in vivo and in vitro. This study compared DHEA, 17α-AED, 17β-AED and 17β-AET for their ability to activate the human AR, ER and GR receptors and determine the relative androgenicity, estrogenicity and glucocorticoid activity. The results show that, at the receptor level, these androstene hormones are weak AR and even weaker ER activators. Direct androstene hormone activation of the human AR, ERα, …


Sphingosine-1-Phosphate And Fingolimod (Fty720) Regulate Icl,Swell In Hl-1 Cardiac Myocytes Via Intracellular Binding And Mitochondrial Ros Production, Pooja Desai Jan 2013

Sphingosine-1-Phosphate And Fingolimod (Fty720) Regulate Icl,Swell In Hl-1 Cardiac Myocytes Via Intracellular Binding And Mitochondrial Ros Production, Pooja Desai

Theses and Dissertations

Swelling-activated Cl− current (ICl,swell) is an outwardly-rectifying current that plays an important role in cardiac electrical activity, cellular volume regulation, apoptosis, and acts as a potential effector of mechanoelectrical feedback. Persistent activation of ICl,swell has been observed in models of cardiovascular disease. We previously suggested sphingosine-1-phosphate (S1P) activates volume-sensitive Cl- current (ICl,swell) by ROS-dependent signaling. S1P and its analog, FTY720 (fingolimod), primarily act via G-protein coupled receptors (S1PR; S1PR1-3 in heart), but several intracellular S1P ligands are known. We investigated how these agents regulate ICl,swell. ICl,swell was elicited by bath S1P (500 nM), FTY720 (S1PR1,3 agonist; 10 μM), and SEW2871 …


Effects Of Short-Term Dewatering On Grazer Abundance And Algal Biomass In A Wastewater Treatment Algal Turf Scrubber, Emily Husted Jan 2013

Effects Of Short-Term Dewatering On Grazer Abundance And Algal Biomass In A Wastewater Treatment Algal Turf Scrubber, Emily Husted

Theses and Dissertations

Finding a new, clean, and sustainable energy source to replace fossil fuels is one of society’s most daunting challenges. Algae biomass is a promising renewable resource for biofuel production due to its efficient conversion of solar energy into chemical energy. Algal turf scrubbers (ATS™) systems mimic natural streams, flowing wastewater over hard substrates designed to encourage attached algae growth. This study focuses on the use of replicated ATS™ systems, because they are low maintenance, are effective for removing nutrient pollutants, model natural stream ecosystems, and can produce large volumes of harvestable algal feedstock for biofuel production. A challenge that occurs …


Estimation Of Aerosolized Antibiotic Resistant Bacteria Concentrations From Wastewater Treatment Facilities Using Spatially-Based Dispersion Modeling, Renee Nichole Dickman Jan 2013

Estimation Of Aerosolized Antibiotic Resistant Bacteria Concentrations From Wastewater Treatment Facilities Using Spatially-Based Dispersion Modeling, Renee Nichole Dickman

Theses and Dissertations

Pathogenic bacteria can develop resistance to antibiotics to which they were previously sensitive, resulting in increased morbidity and mortality worldwide [1]. The increase in drug resistance in bacteria is an emerging public health concern. The activated sludge tanks of wastewater treatment plants are known sources of antibiotic resistant bacteria. These resistant bacteria can become aerosolized and disperse downwind. Using previously sampled aerosol concentrations and meteorological data, a Gaussian dispersion model was developed to estimate the concentration downwind from a selected wastewater treatment facility. The emission rate was calculated to be 7,941 CFU/m²/sec ± 2,149 CFU/m²/sec. This value was used in …


Examining The Differences In Rapport Between Male And Female Cancer Genetic Counselors And Female Clients, John Abernethy Jan 2013

Examining The Differences In Rapport Between Male And Female Cancer Genetic Counselors And Female Clients, John Abernethy

Theses and Dissertations

Genetic counseling is a field in which client-counselor rapport plays a critical role in client satisfaction with the genetic counseling process. One factor that may impact this rapport is gender of the genetic counselor. Previous studies in the field of psychological counseling suggest that gender is not a significant moderator of this rapport. To the best of our knowledge, no study has been published in the field of genetic counseling examining the impact that the gender of the genetic counselor has on client-counselor rapport. To study this effect, an amended version of Horvath & Greenberg's (1989) Working Alliance Inventory tool …


Quantifying The Effects Of Antibiotics Upon Benthic Diatoms And Marine Benthic Algal Communities, Isaac M. Hagenbuch Jan 2013

Quantifying The Effects Of Antibiotics Upon Benthic Diatoms And Marine Benthic Algal Communities, Isaac M. Hagenbuch

Theses and Dissertations

Antibiotics are a cornerstone of modern medicine. Their ability to impair prokaryotic metabolism has saved the lives of many millions of humans in the decades since wide antibiotic usage began. Antibiotic compounds are also widely used in the husbandry of animals that are used for food but, unfortunately, much of the antibiotic mass that goes into humans and animals is excreted unchanged. Those excretions go, directly or indirectly, into aquatic ecosystems. The discovery of this fact has led to a growing global concern about the fate of antibiotics in the environment. This concern is driven by no fewer than three …


Adverse Outcome Pathways: A Framework For Identifying Chemical Mode Of Action During Zebrafish Embryogenesis, Krystle Yozzo Jan 2013

Adverse Outcome Pathways: A Framework For Identifying Chemical Mode Of Action During Zebrafish Embryogenesis, Krystle Yozzo

Theses and Dissertations

Human health and ecological risk assessors are currently facing increased demands and public pressure to evaluate the potential risk of hundreds to thousands of chemicals based on limited toxicity data. Therefore, scientifically sound models are needed to predict toxicity without sole reliance on conventional whole-organism (vertebrate) bioassays. To help address this challenge, adverse outcome pathways (AOPs) have recently been proposed as conceptual tools to help link direct, molecular-level initiating events to adverse outcomes at higher levels of biological organization. Additionally, using AOPs as frameworks, high-throughput screening (HTS) and high-content screening (HCS) assays have been recently proposed as key components of …


Transformations And Fates Of Terrigenous Dissolved Organic Matter In River-Influenced Ocean Margins, Cedric Gael Fichot Jan 2013

Transformations And Fates Of Terrigenous Dissolved Organic Matter In River-Influenced Ocean Margins, Cedric Gael Fichot

Theses and Dissertations

Rivers contribute about 0.25 Pg of terrigenous dissolved organic carbon (tDOC) to the ocean each year. The fate and transformations of this material have important ramifications for the metabolic state of the ocean, air-sea CO2 exchange, and the global carbon cycle. Stable isotopic compositions and terrestrial biomarkers suggest tDOC must be efficiently mineralized in ocean margins. Nonetheless, the extent of tDOC mineralization in these environments remains unknown, as no quantitative estimate is available. The complex interplay of biogeochemical and physical processes in these systems compounded by the limited practicality of chemical proxies (organic biomarkers, isotopic compositions) make the quantification …


Optimal Cooperation In Joint Action Tasks, Scott Michael Blanchette Jan 2013

Optimal Cooperation In Joint Action Tasks, Scott Michael Blanchette

Theses and Dissertations

Joint action can be succinctly defined as an action in which two or more individuals work together for a common outcome. There have been numerous studies on the mechanisms behind joint action, but none have focused on the existence of optimal cooperators. The present study investigated if optimal cooperators, individuals who are better partners in joint action tasks, exist in the population. Individuals completed a virtual bar balancing task in dyads in which four hands were used to control the bar. Based on success rate, significant differences in performance variables were found. This study provides empirical evidence that some individuals …


Measuring Organizational Member Involvement In Physical Activity Coalitions Across The United States, Daniel Benjamin Bornstein Jan 2013

Measuring Organizational Member Involvement In Physical Activity Coalitions Across The United States, Daniel Benjamin Bornstein

Theses and Dissertations

Physical inactivity has been labeled a global pandemic with enormous economic, social, environmental, and public health consequences. The vast majority of American adults and youth are insufficiently physically active. Increasing population-levels of physical activity (PA) requires broad social and environmental change. PA coalitions provide the structure through which such broad change can be achieved. An extensive literature on health-based coalitions suggests that coalition success is impacted by coalition members. Coalitions are generally comprised of member organizations. Little is known about the characteristics of PA coalitions and less is known about organizational member involvement in PA coalitions. The purpose of this …


Classroom Exercise Breaks And Educational Outcomes In Elementary School Students, Erin Kaye Howie Jan 2013

Classroom Exercise Breaks And Educational Outcomes In Elementary School Students, Erin Kaye Howie

Theses and Dissertations

Previous research has shown that physical activity may have beneficial effects on cognitive performance and academic achievement in children, but the optimal type and dose are unknown. Classroom exercise breaks are one type of physical activity opportunity in schools, with the potential to reach a large number of children. The purpose of this dissertation was to describe the prevalence and characteristics of classroom exercise breaks in central South Carolina, and to determine the acute effects of classroom exercise breaks on executive functions, math performance, on-task behavior and affective responses in 9 to 12 year-old children. Additionally, the dissertation examined the …


The Effects Of A High Fat Diet On Mitochondrial Biogenesis And Inflammation In The Brain., Lauren Suzanne Vervaecke Jan 2013

The Effects Of A High Fat Diet On Mitochondrial Biogenesis And Inflammation In The Brain., Lauren Suzanne Vervaecke

Theses and Dissertations

INTRO: High fat diets (HFD) ingested over long periods of time have been shown to cause diet induced obesity leading to excessive adiposity and chronic low grade inflammation. Here we have shown how differing levels of saturated fats (SF), which are common storage fats, affect markers of inflammation and mitochondrial biogenesis. IL-1â and TNF-alpha are pro-inflammatory cytokines that have been shown to increase with a HFD, while molecular signalers, PGC-1alpha, cyt c, and SIRT1, related to mitochondrial biogenesis have been shown to decrease. Despite the risks of consuming a diet high in SF's, consumers continue to buy energy dense foods …


Use Of Social Media As A Support Network In Families With A Child Diagnosed With Trisomy 13, 18, Or 21, Ginger Elizabeth Edwardsen Jan 2013

Use Of Social Media As A Support Network In Families With A Child Diagnosed With Trisomy 13, 18, Or 21, Ginger Elizabeth Edwardsen

Theses and Dissertations

Social media is a web based technology that allows individuals to communicate with other individuals, organizations, and communities about common interests and experiences. Recently, social media use has expanded into the healthcare field and many individuals are using social media to connect with others in similar situations and find support. Family members of children or pregnancies with trisomy 13, 18, or 21 were invited to participate in an online survey that explored the use of social media as a support network including their purposes for using social media as a support network, how often the use social media, and what …


Insects As Indicators Of Environmental Stress, De Anna Estella Beasley Jan 2013

Insects As Indicators Of Environmental Stress, De Anna Estella Beasley

Theses and Dissertations

In the face of climate change-related events and anthropogenic disturbances, understanding the impacts of these events on species richness, abundance and distribution is important for us to mitigate biodiversity loss and better predict consequences for the environment and for human life. Insects are excellent models for understanding the consequences of environmental stress due to the sensitivity of their development and behavior. The overall focus of my dissertation research is the investigation of fluctuating asymmetry and oviposition behavior as indicators of environmental stress. My research includes a meta-analysis of published literature, and empirical research that was part of a collaborative initiative …


The Reproductive Ecology Of Plethodontid Salamanders In The South Carolina Inner Coastal Plain, Heather Rena Oswald Jan 2013

The Reproductive Ecology Of Plethodontid Salamanders In The South Carolina Inner Coastal Plain, Heather Rena Oswald

Theses and Dissertations

Nest- site selection is a critical process in the life history of amphibians, directly influencing offspring survival and parental fitness. When and where an amphibian chooses to nest is strongly influenced by a range of environmental cues. We monitored plethodontid salamander breeding behavior in seepage wetlands in the South Carolina inner Coastal Plain. Seepage wetlands are ideal for monitoring semiaquatic salamander breeding, because they provide habitat for both larval and adult salamanders while having relatively predictable, constant water temperatures and presence year round. We observed the breeding phenology of three sympatric salamanders (Eurycea cirrigera, Desmognathus auriculatus, and Pseudotriton ruber) in …


The Mechanisms Of Posterior Shoulder Tightness And Effectiveness Of Manual Therapy, Lane Brooks Bailey Jan 2013

The Mechanisms Of Posterior Shoulder Tightness And Effectiveness Of Manual Therapy, Lane Brooks Bailey

Theses and Dissertations

Posterior shoulder tightness is a common physical impairment in overhand baseball athletes presenting with injury. The etiology of this physical impairment is poorly understood and theorized to be a combination of bony, muscular, and inert soft-tissue contributions occurring at the glenohumeral joint. The ability to discriminate between each tissue's influences on shoulder range of motion is often challenging to overcome within a clinical environment. Chapter 2 of this manuscript provides a thorough review of the literature discussing the potential mechanisms of posterior shoulder tightness. Previous studies have independently accounted for the relationships between posterior shoulder tightness, and the mechanical contributions …