Life Sciences Commons^™

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 …

Characteristics Of Quality Agricultural Magazine Capstone Courses Based On The Five R'S Model, Traci Nicole Rushing

Graduate Theses and Dissertations

This study sought to assess students' and instructors' perceptions regarding the value of an agricultural communications magazine capstone course at three universities that were identified as exemplary in an effort to describe the characteristics leading to the course's success. Using a qualitative survey methodology, the investigator administered an open-response survey, conducted personal interviews with purposively-selected students in each course and the instructors, and made field observations. Both the interviews and the surveys consisted of six, in-depth questions crafted after Andreasen's (2004) of a successful magazine capstone course. Based on students' and instructors' perceptions through the lens of Andreasen's (2004) model, …

Evaluation Of Internal Markers For Predicting Digestibility And Fecal Output By Cattle Fed Bermudagrass Hays Of Varying Quality, Juvenal Kanani

Graduate Theses and Dissertations

The potential of in situ rumen undegradable dry matter (RUDM), indigestible neutral-detergent fiber (INDF), indigestible acid-detergent fiber (IADF), acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict digestibility (DMD) and fecal output (FO) by cattle fed bermudagrass [Cynodon dactylon (L.) Pers.] hay-diets categorized by their low (L), medium low (ML), medium high (MH), or high (H) CP concentrations (79, 111, 131, and 164 g/kg DM, respectively) was evaluated. The second objective was to evaluate the effects of time (0600, 1200, 1800, and 2400 h) of fecal sampling on the prediction of FO and DMD. A replicated …

Determination Of Methionine And Lysine Requirements Of Growing Broilers Using The Ideal Protein Concept, Changji Lu

Graduate Theses and Dissertations

Three experiments were conducted to evaluate the responses of broiler performance to Lysine (Lys) and Methionine (Met) during the starter, grower, and finisher feeding phases. All the experimental diets were formulated based on the Ideal Protein Concept.

Experiment 1 evaluated the responses to Lys and Met on live performance of young broiler chickens from 0 to 18 d of age. The mean amino acid ratios to Lys suggested by literature values were used in the formulation based on the Ideal Protein Concept. Six levels of Lys and eight levels of supplemental Met were used in the diets resulting in a …

The Impact Of Selected Forage Legumes On Cattle Performance, Forage Production, And Soil Quality, And Evaluation Of Legume Persistence Under Grazing, Bradley Edward Briggs

Graduate Theses and Dissertations

Interest in substituting legumes for N fertilizer in beef cattle grazing systems has recently increased with rising fertilizer prices. Legumes are well known for their ability to fix atmospheric N and decrease dependence on input of N fertilizer. However, there are still difficulties associated with legume utilization including establishment and persistence. Two experiments were conducted to evaluate legume performance under herbivory. The objective of Experiment 1 was to compare forage production and beef cattle gains from annual ryegrass [Lolium multiflorum (L.)] and bermudagrass [Cynodon dactylon (L.) Pers.] pastures fertilized with N or overseeded with legumes. Gelbvieh × Angus …

Characterization And Consumer Acceptance Of White Striping In Broiler Breast Fillets, Vivek Ayamchirakkunnel Kuttappan

Graduate Theses and Dissertations

White striping is an emerging issue in the broiler meat industry which causes concerns among the producers. The condition is characterized by the occurrence of white striations, parallel to the direction of muscle fibers, mainly in broiler breast fillets and thighs. Fillets can be categorized as NORM (normal or no striping), MOD (moderate) and SEV (severe) depending on the degree of white striping. As a result of few previous research studies on the condition, there is no information available on the impact of white striping on the consumer acceptance and various meat quality attributes. Our hypothesis was that the occurrence …

Genotypic And Phenotypic Diversity Of Pyricularia Oryzae In The Contemporary Rice Blast Pathogen Population In Arkansas, Lu Zhai

Graduate Theses and Dissertations

Rice blast, caused by Pyricularia oryzae (teleomorph: Magnaporthe grisea), is one of the most economically important diseases of rice worldwide, including Arkansas. Rice blast has been severe the past few years on conventional cultivars and, more recently, has been observed on hybrid rice cultivars. The first objective of the current research was to examine the genotypic and phenotypic variation in the P. oryzae population in Arkansas during the 2009, 2010, and 2011 growing seasons and compare isolates from conventional cultivars with those from and hybrids. A total of 904 isolates were recovered from symptomatic rice cultivars in Arkansas and …

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 …

Effect Of Enzymatic Treatments On The Physiochemical Properties Of Different Corn Starches, Curtis Robert Luckett

Graduate Theses and Dissertations

Amylose readily reassociates to form films and crystalline structures that are resistant to digestion by amylolytic enzymes and known as resistant starch type III (RS3). This study investigated the RS3 formation and cereal coating properties from enzyme-modified corn starches with varying amylose contents, including Hylon VII (70% amylose), Hylon V (50% amylose), and common corn (25% amylose). For RS3 formation, corn starches were first gelatinized and then hydrolyzed using β-amylase to varying degrees. The resultant hydrolyzed starch was debranched with isoamylase and then exposed to 3 times of temperature cycling at 135/133/133°C for 30 min and 95°C for 24 hr …

Genome-Wide Identification Of Conditionally Essential Genes In Salmonella Typhimurium Using Tn-Seq Method, Anita Khatiwara

Graduate Theses and Dissertations

ABSTRACT

As more whole genome sequences become available, there is an increasing need for high-throughput methods that link genes to phenotypes and facilitate discovery of new gene functions. The objective of this study was to develop a high-throughput method to study gene functions in bacteria and use this method to study gene functions of S. enterica serotype Typhimurium (S. Typhimurium) under various environmental conditions encountered during its life cycle. Chapter I of this dissertation reviews the history and evolution of functional genomics in bacteria with focus on Salmonella, along with the recent techniques available. Chapter II, deals with the development …

Utilization Of Natural Green Tea And Grape Seed Extracts And Nisin To Reduce Conventional Chemical Preservatives And To Inhibit The The Growth Of Listeria Monocytogenes In Ready To Eat Low And High Fat Chicken And Turkey Hotdogs, Amara Venkata Sunil Perumalla

Graduate Theses and Dissertations

Ready-to-eat meat (RTE) products such as hotdogs represent a popular segment in convenience food purchases. Increased demand has led the processors to extend the shelf life by minimizing lipid oxidation and post-processing contaminants such as Listeria monocytogenes. There is a growing interest in the food processors and consumers regarding the use of natural alternatives in place of synthetic food additives to control the growth of foodborne pathogens and (or) lipid oxidation. In recent years, green tea (GTE) and grape seed extracts (GSE) are increasing choices as they have demonstrated antioxidant as well as antimicrobial properties in various food applications. …

Role Of Lactic Acid Bacteria As A Bio-Sanitizer To Prevent Attachment Of Listeria Monocytogenes On Deli Slicer Contact Surfaces, And The Influence Of Listeria Innocua On The Attachment Of L. Monocytogenes On Selected Materials Located In The Food-Processing Environment, Jean Baptiste Ndahetuye

Graduate Theses and Dissertations

Listeria monocytogenes an important foodborne pathogen that continues to be a serious problem for the food industry. This pathogen contaminates food primarily during post-harvest in the food-processing environment. Its ecology in the food-processing environment is not well understood but previous research has demonstrated the ability of L. monocytogenes to survive on food contact surfaces after cleaning and disinfection. The current study explored the attachment of three lactic acid bacteria (LAB) strains, Lactobacillus animalis , Lb. amylovorus and Pediococcus acidilactici , their combination in a cocktail, and their influence to prevent the attachment of L. monocytogenes at room temperature by examining …

Characterization Of Novel Histone H2b Mutants Associated With Chromosome Segregation Defects In Saccharomyces Cerevisiae, Thiruchelvam Rajagopal

Graduate Theses and Dissertations

Histones are small basic proteins that associate with DNA to form the basic unit of chromatin, the nucleosome. Histones H3 and H4 form a tetramer that is bound by two H2A-H2B dimers to form the histone octamer, to which approximately 146 bp of DNA wrap around to form the nucleosome. High resolution structural information and recent advances in the understanding of histone post-translational modifications have illuminated the many regulatory functions chromatin exerts in the cell, from the transcriptional control of gene expression to chromosome segregation. However, the specific role that histones play in these processes is not well understood. Previous …

The Role Of Ascorbic Acid In The Plant-Herbivore Interaction, Kelly Ann Carruthers

Graduate Theses and Dissertations

Ascorbic acid (AsA), vitamin C, is an important molecule that is vital for both human and plant health, because it aids in the detoxification of reactive oxygen species (ROS) caused by various abiotic and biotic stresses including UV, salinity, ozone, and attack from pathogens In order to understand the role of AsA in the plant-herbivore interaction, we looked at the effects of the wound-responsive hormones, jasmonate, wounding, and herbivory on AsA content. Our study is the first to directly compare the effects of wounding and jasmonates on AsA levels in plants. We looked at the effects of wounding and methyl …

Genetic Analysis Of Chromosomal Regions Affecting Sperm Mobility In The Chicken (Gallus Gallus Domesticus), Sharath Chandra Munnaluri

Graduate Theses and Dissertations

This project is focused on determining the contributions of particular genetic loci to low sperm mobility in the chicken. Sperm mobility has been shown to be a major determinant of male fertility in broiler breeders. A whole genome SNP scan identified chromosomal regions (QTLs) that control sperm mobility. I used microsatellites from 4 chromosomal regions ( 15.151 on chromosome 6, 12.435 on chromosome Z, 12.341 on chromosome Z, and 17.214 on chromosome Z) to determine the association of these regions with sperm mobility in experimental lines divergently selected for mobility phenotype. Determination of the genetics underlying sperm mobility will identify …

The Relationship Between Chronic Ankle Instability And Functional Movement Impairment In Division I Female Athletes, Akihito Tajima

Graduate Theses and Dissertations

Lateral ankle sprains are the most common injury in athletics (Denegar & Miller, 2002; Ekstrand & Tropp, 1990). In addition, the recurrent rate of ankle sprains is as high as 80% (Smith & Reischl, 1986). Repetitive ankle sprains may lead to a phenomenon known as chronic ankle instability (Hertel, 2002). It has been theorized that there are two main attributions to chronic ankle instability: mechanical and functional instability (Monaghan, Delahunt, & Caulfield, 2006). The exact mechanism of chronic ankle instability is still unclear; however, recent studies focus on multiple factors rather than single measurements, in addition to functional testing. A …

Biological Strategies And Mathematical Approaches For Limiting Bacterial Contaminants And Chemical Pollutants In Bioethanol Fermentations, Alia Chahed Ep Limayem

Graduate Theses and Dissertations

During the most recent decades increased interest in fuel from biomass in the United States and worldwide has emerged each time petroleum derived-gasoline registered well publicized spikes in price. The willingness of the U.S. government to face the issues of more heavily high-priced foreign oil and climate change has led to more investment on plant-derived sustainable biofuel sources. Biomass derived from corn has become one of the primary feedstocks for bioethanol production for the past several years in the U.S. However, the argument of whether to use food as biofuel has led to a search for alternative non-food sources. Consequently, …

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 …

Stable Isotope Analysis (Delta Nitrogen-15 And Delta Carbon-13) And Bioenergetic Modeling Of Spatial-Temporal Foraging Patterns And Consumption Dynamics In Brown And Rainbow Trout Populations Within Catch-And-Release Areas Of Arkansas Tailwaters, Jon M. Flinders

Graduate Theses and Dissertations

I examined spatial and temporal consumption dynamics using an energy intake model and a bioenergetics model of rainbow trout, Oncorhynchus mykiss, and brown trout, Salmo trutta, within three catch-and-release (C-R) areas in Bull Shoals and Norfork tailwaters to determine whether trout populations were limited by food supply. I also examined the seasonal and ontogenetic shifts in the foraging patterns of brown and rainbow trout within these areas using gut content analysis (GCA) and stable isotope analysis (SIA) of C and N. I examined 605 brown trout and 768 rainbow trout for GCA and SIA at Bull Shoals, Norfork, …

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 …

Sanitation Assessment Of Food Contact Surfaces And Lethality Of Moist Heat And A Disinfectant Against Listeria Strains Inoculated On Deli Slicer Components, Sabelo Muzikayise Masuku

Graduate Theses and Dissertations

The overall objectives of this study were to: evaluate the efficacy of different cleaning cloth types and cloth-disinfectant combinations in reducing food contact surface contamination to acceptable levels; determine the optimum moist heat and moist heat + sanitizer treatments that can significantly reduce the number of Listeria strains on deli slicer components; and investigate if the moist heat treatment used in this study induced the viable-but-non-culturable (VBNC) state in Listeria cells. The efficacy of wiping cloths was measured using ATP-bioluminescence and total plate count methods using four different wiping cloths and silver dihydrogen citrate sanitizer on food contact surfaces. The …

Herbicide Resistance Mechanism(S) In Italian Ryegrass (Lolium Perenne Ssp. Multiflorum) Populations In The Southern United States, Reiofeli Algodon Salas

Graduate Theses and Dissertations

Italian ryegrass is a principal weed problem in wheat production fields in the Southern US. Resistance to herbicides diclofop, mesosulfuron, and pinoxaden among ryegrass populations has been reported. Glyphosate-resistant Italian ryegrass populations were identified in Desha County, Arkansas. This research aimed to 1) determine resistance patterns to ACCase (diclofop and pinoxaden) and ALS (imazamox, mesosulfuron, and pyroxsulam) herbicides among Italian ryegrass populations from the southern US; 2) determine if cytochrome P450-mediated enhanced herbicide metabolism contributed to resistance; and 3) elucidate the resistance mechanism to glyphosate in four Arkansas populations (Des03, Des05, Des14, and D8). For objective 1, 30 accessions from …

Diversity, Identification, Mapping And Pyramiding Of Genes For Resistance To Soybean Mosaic Virus [Glycine Max (L.) Merr.], Innan Gloria Cervantes Martinez

Graduate Theses and Dissertations

Soybean Mosaic Virus (SMV) is a prevalent viral pathogen transmitted by aphids and via seed, causing significant yield loss and quality reduction. There are seven SMV strain groups (G1 to G7) and three resistance loci( Rsv1, Rsv3, and Rsv4) reported in soybean. New sources of SMV resistance would be valuable for breeding cultivars with durable resistance to multiple strains. The objectives of this research were to analyze genetic diversity of SMV-resistant soybean germplasm at the molecular level; to pyramid three genes from different sources for durable SMV resistance; and to identify and map new genes/alleles for differential reactions to SMV …

Electrospun Polycaprolactone Nanofiber Scaffolds For Tissue Engineering, Andreas Haukas

Graduate Theses and Dissertations

Stem cell and tissue engineering offer us with a unique opportunity to research and develop new therapies for treating various diseases that are otherwise incurable using traditional medicines. However, development of these new therapies replies upon the establishment of in vitro cell culture and differentiation systems that mimic in vivo microenvironments required for cell-cell and cell-ECM interaction. The development of these cell culture systems depends upon the identification of appropriate biomaterials and cell sources. Biomaterials should be carefully selected and fabricated into scaffolds for supporting cell growth and differentiation. In this study, we explored the fabrication of 3D electrospun nanofiber …

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 …

Lameness Associated With A Possible Neural Problem In The Lower Spinal Cord Of Chickens, Gallus Gallus, Gurueswar Nagarajan

Graduate Theses and Dissertations

Since the second half of the twentieth century lameness in broiler chickens has been known to be caused by different types of disorders, however the etiology of several type of lameness remain unknown. Because of the intense selection of broilers for rapid growth, some birds are more prone to physiological insults resulting in lameness. This study focuses on possible neural problems in the lower spinal cord associated with lameness in broilers. Broilers were raised in pens with wire floors and provided with food and water ad libitum. Three groups of birds 1) birds displaying a normal gait (Controls), 2) lame …

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 …

Feed Supplementation With Natural Extracts Of Cranberry And Its Efficacy On Campylobacter Colonization In Poultry, Ann Woo-Ming

Graduate Theses and Dissertations

Campylobacter spp. has been identified as one of the leading causative agents of food borne diarrheal illness. Epidemiological evidence has shown that poultry is the main source for human infection. Poultry are asymptomatic carriers of Campylobacter within their gastrointestinal tract, with colonization levels reaching 106-108 cfu/g cecal content. Surveys of domestic poultry flocks have estimated that approximately 90% of flocks are positive for Campylobacter colonization. Risk assessment studies have determined that by reducing levels of Campylobacter colonization during rearing, incidences of human infection will be significantly reduced. Currently there are no consistently effective treatments to eliminate Campylobacter from poultry flocks. …

Effects Of Management Strategies And Molecular Breeding Values On Cattle Performance And Carcass Traits, Benjamin Collins Williamson

Graduate Theses and Dissertations

Forty-eight Gelbvieh x Angus steers (265 ¡À 40 kg) were utilized to determine the relationships among molecular breeding values (MBV), steer performance, and carcass traits. Body weight (BW), hip height (HH), hip width (HW), exit velocity (EV; rate at which steers exited the squeeze chute and traversed 1.8 m) and body ultrasound measurements of steers were recorded at d 0, 93 and 154 of grazing mixed stockpiled endophyte-infected and -free tall fescue. Tissue samples were collected for genomic profiling (Igenity, Merial Limited, Duluth, GA). Steers were transported to the Oklahoma State U fed for 159 d, harvested and carcass parameters …

Territories,Territoriality, And Conservation Of The Louisiana Waterthrush And Its Habitat, The Watershed Of The Upper Buffalo National River, Leesia Cheryl Marshall

Graduate Theses and Dissertations

The Louisiana Waterthrush, Parkesia motacilla, is a migratory wood-warbler and breeding season resident of the eastern United States. Males defend breeding territories that extend linearly along clear, fast-flowing, gravel-bottomed, forest streams. Defense includes two song types, primary and extended song. As riverine specialists, birds rely upon aquatic invertebrates as prey and riparian habitat features for nesting. They use a unique foraging maneuver, leaf-pulling, that involves picking up or pulling a leaf from water, and turning it over to search for prey. Their relationship with riparian habitat introduces potential for Louisiana Waterthrushes to serve as indicators of stream health. The …