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Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou Dec 2012

Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou

Graduate Theses and Dissertations

Soybean vein necrosis disease (SVND) is widespread in major soybean-producing areas in the U.S. The typical disease symptoms exhibit as vein clearing along the main vein, which turn into chlorosis or necrosis as season progresses. Double-stranded RNA isolation and shot gun cloning of symptomatic tissues revealed the presence of a new tospovirus, provisionally named as Soybean vein necrosis associated virus (SVNaV). The presence of the virus has been confirmed in 12 states: Arkansas, Illinois, Missouri, Kansas, Tennessee, Kentucky, Mississippi, Maryland, Delaware, Virginia and New York. Symptomatic samples collected from eight states (AR, IL, MO, MS, KS, TN, MD and DE), …


False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen Dec 2012

False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen

Graduate Theses and Dissertations

False smut of rice, caused by Ustilaginoidea virens (Cooke) Takahashi (Teleomorph: Villosiclava virens), has become a common disease in most major rice growing regions throughout the world. Considerable confusion exists regarding the infection process and the disease cycle. Therefore, a clearer understanding of pathogenesis caused by Ustilaginoidea virens is critical for future efforts to develop genetic and chemical tools to manage false smut in Arkansas and other regions of the world. The overall goal of this research was to clarify the infection process underlying false smut, with emphasis on comparing and contrasting the histological basis of root and foliar infections. …


Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame Dec 2012

Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame

Graduate Theses and Dissertations

Rising feed costs, environmental pollution concerns targeted at animal agriculture, a worldwide focus on sustainability and the never ending battle to improve production and efficiency within the poultry industry challenges nutritionists to focus on products to improve nutrient digestibility and decrease feed costs while at the same time maximizing performance. The research presented in this dissertation focuses on improving nutrient utilization of protein sources with protein liberating enzymes currently available commercially. The research also conducted addresses the addition of crystalline amino acids valine and isoleucine and their effect on improving efficiency of broilers.

The first research project compared the efficacy …


Assessing The Impacts Of Surface Water Removal For Use In Natural Gas Extraction On A Watershed Level, Carrie Ann Davis Dec 2012

Assessing The Impacts Of Surface Water Removal For Use In Natural Gas Extraction On A Watershed Level, Carrie Ann Davis

Graduate Theses and Dissertations

In this study, the Soil and Water Assessment Test (SWAT) was used as a tool to predict whether diffuse water removal from the Cadron Creek watershed for use with natural gas development would have an impact on downstream flow within the watershed. Cadron Creek watershed expands across four counties within Arkansas and is located in the Fayetteville Shale Gas region. This region is experiencing significant growth in natural gas development. Successful development of shale gas depends on the identification of what water supplies are available for production without interfering with community and environmental needs. The SWAT model used to evaluate …


A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh Dec 2012

A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh

Graduate Theses and Dissertations

This study compares a novel simulation approach to the conventional Soil and Water Assessment Tool (SWAT) modeler's approach for targeting biofuel crop production on marginal lands. In conventional SWAT modeling approach, non-spatial definition of hydrological response units (HRUs) results in the simulation of biofuel crops on both marginal and non-marginal land. This study provides an alternative approach in which a marginal-land raster was integrated into the land use and land cover (LULC) raster in such a way that the land uses were divided into marginal and non-marginal components. This modified LULC was used for model setup which resulted in marginal …


An Ethnographic Case Study Of A Deaf Workforce Collective, Peter Shane Butler Dec 2012

An Ethnographic Case Study Of A Deaf Workforce Collective, Peter Shane Butler

Graduate Theses and Dissertations

This ethnographic study seeks to increase our understanding of the individual and shared experiences of five members of a Deaf United States Postal Service (USPS) collective employment cohort in regards to their early learning experiences, how these experiences led to collective employment, and how the collective employment opportunity led them to establish a new Strong Deaf Community in Houston. The data collected through semi structured interviews will be used to increase our understanding about how Strong Deaf Communities form, and what purpose they serve for grassroots members.

This study also seeks to shed light on why it is critical for …


Predictors Of Academic Success For The National Board Dental Hygiene Examination And The Southern Regional Testing Agency Clinical Exam, Melissa Gail Efurd Dec 2012

Predictors Of Academic Success For The National Board Dental Hygiene Examination And The Southern Regional Testing Agency Clinical Exam, Melissa Gail Efurd

Graduate Theses and Dissertations

The purpose for conducting this study was to investigate and describe the relationship between applicant criteria for a dental hygiene program and subsequent outcomes on credentialing exams: the National Board Dental Hygiene Exam and the Southern Regional Testing Agency clinical exam. Because admission criteria play a crucial role in applicant selection, choosing students, that will successfully complete the program as well as the necessary credentialing exams, is a particularly crucial task for admission committees. The study had three elements. First, it investigated the relationship between the variables of age, undergraduate GPA and scores from the Psychological Services Bureau Health Occupations …


Effect Of Body Size And Exercise On Mood State, Alexandra Lachance Dec 2012

Effect Of Body Size And Exercise On Mood State, Alexandra Lachance

Graduate Theses and Dissertations

Exercising in the presence of nature (i.e., "green exercise"), has been shown to heighten the physiological and mental benefits of traditional exercise on non-obese individuals. The effects of green exercise on obese individuals are unknown. It is hypothesized that green exercise is more beneficial for obese (greater positive improvements in mental health scores), compared to non-obese individuals. For example, the benefits of green exercise could help lower feelings of depression, improve mood and self-esteem to increase the propensity of obese individuals to meet exercise recommendations. Accordingly, this study investigated the physiological and psychological effects of green exercise on 12 obese …


Food Environment And Childhood Obesity, Yucong Jiao Aug 2012

Food Environment And Childhood Obesity, Yucong Jiao

Graduate Theses and Dissertations

This thesis examines whether children's food environment, especially food stores that have fresh produce, affects obesity prevalence among elementary school children in the state of Arkansas. Misclassified food outlet types in the Dun and Bradstreet commercial data set were first corrected and then food environment measures were computed and aggregated to geographic regions corresponding to school attendance areas. After applying classical panel estimation, it was found that the fixed effects model fit the data best. Results indicate that an additional supermarket within a one-mile radial of the census neighborhood block center will bring down childhood obesity prevalence by 0.58 percent, …


Livestock Production And Wildlife-Based Tourism: Articulating Land-Use And Policy Conflicts In The Okavango Delta Ramsar Site In Botswana, Nelson Kgamanyane Sello Aug 2012

Livestock Production And Wildlife-Based Tourism: Articulating Land-Use And Policy Conflicts In The Okavango Delta Ramsar Site In Botswana, Nelson Kgamanyane Sello

Graduate Theses and Dissertations

The management of common pool resources and policy conflicts between livestock and wildlife, two land-use types that take place in the same geo-spatial area has been a subject of debate among scholars for decades. This conflict in policies has engendered in communities which are beneficiaries attitudes that are either negative towards wildlife or favorable depending on the benefits they derive from them. This research therefore set out to understand the conflicts in the management of the Okavango Delta Ramsar Site (ODRS) where the OD is situated. The study used the grounded theory to collect and analyze the data in the …


The Role Of Antioxidant Rich Berries In The Prevention Of Postmenopausal Bone Loss, Lydia Karimi Kaume Aug 2012

The Role Of Antioxidant Rich Berries In The Prevention Of Postmenopausal Bone Loss, Lydia Karimi Kaume

Graduate Theses and Dissertations

Postmenopausal osteoporosis is the most prevalent form of osteoporosis and results in fragility fractures. Smoking is one of the major risk factors for osteoporosis and is known to aggravate bone loss in postmenopausal women due to increased oxidative stress and inflammation. Diet-based interventions using berries have shown bone protective affects in animal studies partially due to antioxidant and anti-inflammatory properties of their phenolic compounds. The goal of this research was to determine the effects of antioxidant-rich fruits in the prevention of postmenopausal bone loss. Our first study examined the dose dependent effects of blackberries in preventing bone loss in an …


Superfund Evaluation: The Families Of Tar Creek, Gary D. Wilson Aug 2012

Superfund Evaluation: The Families Of Tar Creek, Gary D. Wilson

Graduate Theses and Dissertations

The Tar Creek Superfund Site is located in far northeastern Oklahoma near the Oklahoma/Kansas border in Ottawa County. The Site generally consists of a forty-square-mile area which is also part of the larger Tri-State Mining District that includes areas of Kansas and Missouri. The Site includes parts of five communities: Picher, Cardin, Quapaw, North Miami, and Commerce in Oklahoma. It also includes Treece, Kansas, and affects a total population of roughly 30,000 residents. Following Superfund designation, families in the Tar Creek area had to decide whether to accept or reject buy-out offers. This project explored the decision-making processes employed by …


The Effects Of Body Modifications And Dress On Perceived Professionalism And Competency Of A Female Model, Ashley Donell Aug 2012

The Effects Of Body Modifications And Dress On Perceived Professionalism And Competency Of A Female Model, Ashley Donell

Graduate Theses and Dissertations

Through the norms of a society, people must meet certain expectations in order to survive and provide for their family. For example, job expectations driven by human judgment on appearance creates a norm that society must follow. The question is how much appearance attributes such as dress and hair color effect others' interpretation of who a person may be? The purpose of this study was to evaluate the relationship between specific appearance and body modifications (dress and hair color) of a young female professional and perceived competency level as determined by a convenience sample of students in selected senior level …


Effects Of Head Position And Head-Supported Mass On Nerve Function Of The Flexor Carpi Radialis Muscle In Healthy Individuals, Bethany Lauren Shivers Aug 2012

Effects Of Head Position And Head-Supported Mass On Nerve Function Of The Flexor Carpi Radialis Muscle In Healthy Individuals, Bethany Lauren Shivers

Graduate Theses and Dissertations

Long-term exposure to head-supported mass (HSM) has been linked with spinal degeneration including foraminal stenosis and disc deterioration. Anecdotally, HSM has also been linked to neck and arm pain and muscle atrophy, but nerve function has not been tested specifically. The combined effect of various head positions and HSM may be sufficient to compress the nerve root in aviators and Soldiers during job performance, potentially leading to short- and long-term neuromuscular effects. The Hoffmann (H) reflex, a well-established measure of nerve function, has shown to be sensitive to changes in nerve root space which occurs with different head positions. This …


Interactions Between The Thermic Effect Of Food And Exercise On Total Energy Expenditure In Moderately Active Females, Ashley Binns Aug 2012

Interactions Between The Thermic Effect Of Food And Exercise On Total Energy Expenditure In Moderately Active Females, Ashley Binns

Graduate Theses and Dissertations

Diet and exercise are key components to overall health maintenance. Aspects contributing to weight maintenance include the thermic effect of food (TEF) and total energy expenditure (TEE), with TEF contributing to upwards of 10% TEE. PURPOSE: The purpose of this study was to determine the interaction between TEF and exercise on TEE in moderately active females. METHODS: A sample population was established with the use of a health history questionnaire (HHQ). Ten active females of normal body composition, determined by body mass index (BMI) and a dual energy absorptiometry x-ray (DEXA) scan, participated in the study. Maximal aerobic …


The Use Of Cortisol And Hba1c As Biomarkers Of Stress In University Administrators, Jacilyn Marie Olson Aug 2012

The Use Of Cortisol And Hba1c As Biomarkers Of Stress In University Administrators, Jacilyn Marie Olson

Graduate Theses and Dissertations

PURPOSE: The purpose of this study was to explore the impact of perceived stress and cardiorespiratory fitness on cortisol and HbA1c, biomarkers of stress, in a group of select university administrators. The impact of gender on these relationships was of special concern. METHODS: University administrators with job titles of Chancellor, Provost, Vice Chancellors and Vice Provosts of the university, and Deans and Associate Deans at the college level were recruited. Twenty-five administrators (15 males and 10 females) agreed to participate and completed a battery of assessments that included completion of the University Administrative Concerns Questionnaire, a finger-stick blood test for …


Multifunctionality In U.S. Rice Production: A Logit Analysis In Farmers Participation, Juan Tur Cardona May 2012

Multifunctionality In U.S. Rice Production: A Logit Analysis In Farmers Participation, Juan Tur Cardona

Graduate Theses and Dissertations

Multifunctional agriculture is particularly fundamental to some working lands conservation policies and programs, such as the Environmental Quality Incentive Program (EQIP), Conservation Security Program (CSP) and Wildlife Habitat Incentive Program (WHIP). Farmers can also be engaged in providing recreational and agri-tourism services such as hunting, fishing, bird-watching, farm tours, petting zoos and hospitality services. Using the Agricultural Resource Management Survey (ARMS) we analyze factors associated with participation in conservation, recreation and agri-tourism activities as a function of farm structure, farm financial measures, production practices, and socio-demographic characteristics of the farm operator. To estimate the functional relationships we estimate a binary …


Investigation Of A Locus On Chromosome 9 For Contributions To Pulmonary Hypertension Syndrome In Broilers, Sriram Krishnamoorthy May 2012

Investigation Of A Locus On Chromosome 9 For Contributions To Pulmonary Hypertension Syndrome In Broilers, Sriram Krishnamoorthy

Graduate Theses and Dissertations

Although the ascites syndrome in chickens has been investigated for years, it continues to inflict financial losses to the world poultry industry. It is estimated that 8% of the 361 million broiler deaths are due to ascites leading to losses of millions of dollars annually. Efforts to curb the incidence of ascites are typically designed to slow early growth. This limits the birds' ability to show its true genetic potential and impacts later yields. In 1994 lines divergent for susceptibility to ascites were established from a commercial sire line through sibling selection of birds reared at local altitude after testing …


Nutrient Dynamics In Stormwater Runoff From Green Roofs With Varying Substrate, John Michael Fohner May 2012

Nutrient Dynamics In Stormwater Runoff From Green Roofs With Varying Substrate, John Michael Fohner

Graduate Theses and Dissertations

One major concern with urban development is the increasing amount of stormwater runoff from large expanses of impervious surfaces. These impervious surfaces reduce the ability of stormwater to infiltrate into the soil and eventually groundwater, which leads to greater amounts of surface runoff. Green technology serves as a viable solution to many of the environmental problems presented by modern development. Fifteen mock, extensive green roofs were built in the fall of 2008 at the Watershed Research and Education Center in Fayetteville, Arkansas. The goals of this project were to (1) measure the amount of stormwater runoff from varying treatments and …


Effect Of Water-Deficit Stress On Cotton During Reproductive Development, Dimitra Loka May 2012

Effect Of Water-Deficit Stress On Cotton During Reproductive Development, Dimitra Loka

Graduate Theses and Dissertations

Water deficit is a major abiotic factor limiting plant growth and crop productivity around the world. Cotton (Gossypium hirsutum L.) is considered to be relatively tolerant to drought and the effects of water stress on leaf physiology and metabolism have been extensively documented. However, information is lacking on the effect of water-deficit stress on the cotton flower. It was hypothesized that water-deficit stress would impair gas exchange functions which consequently would result in perturbation of carbohydrates of cotton reproductive units. To investigate this hypothesis growth room studies and field studies were conducted with the objectives being to document the physiological …


A Role Of Environmental Components In Autoimmune Vitiligo Of Smyth Line Chickens, Lei Dong May 2012

A Role Of Environmental Components In Autoimmune Vitiligo Of Smyth Line Chickens, Lei Dong

Graduate Theses and Dissertations

The Smyth line (SL) of chickens is a well-established animal model for the study of spontaneous autoimmune vitiligo, displaying all the characteristics of human vitiligo. In humans, phenolic derivative 4-tertiary butyl phenol (4-TBP) has been shown to trigger vitiligo in susceptible individuals. In vitiligo-prone SL-chickens, live turkey herpesvirus (HVT) infection at hatch was identified as the most effective trigger of SL-vitiligo expression. This dissertation examined the role of the environmental factors 4-TBP and HVT in the etiology of SL-vitiligo. Specifically, the generation of reactive-oxygen-species by melanocyte-containing feather tissue (MC-FT) and cultured melanocytes in response to 4-TBP exposure in vitro (Study …


Interactions Of Nitric Oxide And Superoxide Pathways In Hyperglycemic Endothelial Cells, Steven Clay Rogers May 2012

Interactions Of Nitric Oxide And Superoxide Pathways In Hyperglycemic Endothelial Cells, Steven Clay Rogers

Graduate Theses and Dissertations

Cardiovascular complications arising from diabetic hyperglycemia represents one of the leading causes of death and greatest public health challenges of modern societies. Despite state-of-the-art glucose control, diabetic patients remain at a markedly increased risk of cardiovascular disease. The loss of endothelial function (the development of diabetic endothelial dysfunction) has been implicated in the development of numerous diabetic cardiovascular diseases. The endothelial cell produces many vasoactive substances, hormones and cytoprotective biological factors. Endothelial cells are also involved in and affected by the initiation of inflammatory responses through the release and interaction of cytokines and other immune system molecules. Therefore, regulation of …


Intake, Digestibility, Insitu Disappearance And Ruminal Fermentation Of Bermuda Grass Hay By Lactating Beef Cows Offered Corn Or Hominy Feed As Supplements, Zibani Madzonga May 2012

Intake, Digestibility, Insitu Disappearance And Ruminal Fermentation Of Bermuda Grass Hay By Lactating Beef Cows Offered Corn Or Hominy Feed As Supplements, Zibani Madzonga

Graduate Theses and Dissertations

Hominy feed, a co-product of dry corn milling, has been evaluated to a limited extent in feedlot and dairy rations, but has not been evaluated as a supplemental energy source for lactating beef cows. The objective of this study was to determine the effect of level of hominy feed supplementation on intake, digestibility, in situ DM disappearance, and ruminal fermentation characteristics of medium quality bermudagrass hay. Five ruminally cannulated lactating beef cows (BW = 596 kg, SE = 13.9) were used in an experiment with a 5 × 5 Latin square design. Treatments were low hominy (LH; 0.25% …


Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan May 2012

Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan

Graduate Theses and Dissertations

Slope failure continues to pose risks to society because knowledge of environmental factors and their interactions are unclear and possibly misunderstood. This misunderstanding leads to generalizations about slope failure susceptibility mapping, despite knowing that slope failures are likely the result of an extensively complex set of interactions among a number of environmental, edaphic, and geomorphic characteristics. Therefore a series of experiments were conducted to investigate the effects of slope, soil texture, vegetation cover, bedrock permeability, and compaction,. A wooden flume with a slope face 1 m wide by 1.5 m long with a 10 cm toe was constructed to contain …


Patient And Nurse Considerations In Home Health Routing With Remote Monitoring Devices, Jessica Spicer May 2012

Patient And Nurse Considerations In Home Health Routing With Remote Monitoring Devices, Jessica Spicer

Graduate Theses and Dissertations

We build on the current consistent vehicle routing problem literature by formulating a novel multi- objective mathematical model of the home health scheduling and routing problem that includes the option of assigning some patient visits to remote monitoring devices, with the objectives of mini- mizing total cost, achieving nurse consistency and creating balanced nurse workloads. A heuristic solution approach that approximates the efficient frontier of this multiobjective problem is pre- sented and validated, and the results of using this methodology to solve several realistic instances are included. We also analyze the assignment of patients to devices and present some managerial …


Systematic Observation Of Coach Feedback In Elite Youth Volleyball, Mark David Mann May 2012

Systematic Observation Of Coach Feedback In Elite Youth Volleyball, Mark David Mann

Graduate Theses and Dissertations

The purpose of the study was to understand the relationship of coach feedback during time-outs to the performance of 16-18 year old volleyball players in competitive match play situations. The systematic observation of coach feedback during 89 time-outs was recorded using the Coach Time-Out Observation Instrument (CTOOI). Out of the 879 feedback statements that were made during the 89 time-outs, the CTOOI categorized coach feedback for technical feedback (with an internal or an external focus), tactical feedback (referring to our team or the opponent), and psychological feedback (as either encouraging or discouraging remarks). Data from the Game Performance Assessment Instrument …


Anxiety And Sleep Disorder Comorbidity: Affecting The College Students' Performances, Amanda Rhenee Grimes May 2012

Anxiety And Sleep Disorder Comorbidity: Affecting The College Students' Performances, Amanda Rhenee Grimes

Graduate Theses and Dissertations

The purpose of this study is to determine the effects that anxiety disorders and sleep disorders have on students' academic performance. The prevalence of both disorders is rising in the college student population. This study examines those who have been physician diagnosed with the one or both of the disorders and how the students' grade point average (GPA) is affected.

The National College Health Assessment was used for data collection; this survey assesses college students' health habits, behaviors, and perceptions. The sample was comprised of 57 institutions representing every region in the U.S. totaling 34,208 participants. Data was acquired through …


Comparison Of Sport Competitive Anxiety Levels Of Saudi Arabian National Team Athletes With And Without Disabilities In Competitions, Hassan Ahmad Halawani May 2012

Comparison Of Sport Competitive Anxiety Levels Of Saudi Arabian National Team Athletes With And Without Disabilities In Competitions, Hassan Ahmad Halawani

Graduate Theses and Dissertations

Anxiety in sport is complex and can lead to a number of undesirable consequences such as burnout, performance difficulties, interpersonal problems, and injury. The purpose of this study was to compare whether significant differences existed in the levels of somatic anxiety, worry, and concentration disruption between individuals of the Saudi Arabian national team with and without disabilities in competitions. In addition, differences in somatic anxiety, worry, and concentration disruption were examined between athletes in an individual or team sport. The Sport Anxiety Sale (SAS-2, Smith et. al, 2006) was employed to measure the subscales of somatic anxiety, worry, and consternation …


Individual Resilience, Social Support, And Health Risk Behaviors In Adolescents And Young Adults: Study On Cross-Sectional And Longitudinal Samples, Chuong Hong Nguyen May 2012

Individual Resilience, Social Support, And Health Risk Behaviors In Adolescents And Young Adults: Study On Cross-Sectional And Longitudinal Samples, Chuong Hong Nguyen

Graduate Theses and Dissertations

Resilience is considered the ability that a person gains positive achievements despite exposure to significantly adverse life conditions. However, a majority of previous research has focused on human developmental tasks or academic achievements. Evidence of resilience on health risk behaviors has not been comprehensively established yet. The purposes of this dissertation were to extend the existing literature about the stability of resilience through time, to examine how the resilience scale concurrently and prospectively predict resilience statuses, and to explore effects of Social support over a long period of lifetime. The dissertation used a secondary database from the public-use version of …


The Correlation Between Hip Abductor Strength And Functional Performance In Division I Female Collegiate Soccer Athletes, Caitlin Elizabeth Whale May 2012

The Correlation Between Hip Abductor Strength And Functional Performance In Division I Female Collegiate Soccer Athletes, Caitlin Elizabeth Whale

Graduate Theses and Dissertations

Division I female soccer athletes have been documented to succumb to the greatest amount of lower extremity injuries, predominately ACL injuries. The risk for a lower extremity injury becomes greater when alterations to functional biomechanics are present. Specifically, the hip abductor strength has a crucial role in maintaining pelvic alignment. The purpose of this study was to determine if the hip abductor strength of a female athlete alters' biomechanics during functional performance. Thirty-two Division I female soccer athletes participated in this study (20+2yrs, 64.5+16.5kg, 166+14cm). Descriptive and anthropological statistics were recorded prior to participation. The athletes' isometric hip abductor strength …