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Early Season Population Dynamics And Residual Insecticide Effects On Bird Cherry-Oat Aphid, Rhopalosiphum Padi In Arkansas Winter Wheat, Beven Mcwilliams

Graduate Theses and Dissertations

Bird cherry-oat aphid is a common pest of Arkansas winter wheat. This aphid vectors barley yellow dwarf virus which may cause extensive crop damage and yield loss when wheat is infested by virulent aphids in the fall. Some suggest this damage may be avoided using insecticide seed treatments if growers are unable to delay planting, as is recommended. Field population dynamics of bird cherry-oat aphid during fall 2009 and 2010 was assessed through random sampling of whole plants and pan trapping methods to evaluate aphid immigration. The field plots were divided into four subplots treated with a systemic insecticide seed …

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 …

Disgust Sensitivity, Sexual Trauma History, And Female Sexual Functioning, Tara Mcgahan

Graduate Theses and Dissertations

Sexual dysfunctions are a common problem for women that negatively impact quality of life (Laumann, Paik, & Rosen 1999). A history of sexual trauma is associated with an increase in sexual difficulties (Neumann et al., 1996). One common reaction to unwanted sexual contact is disgust (Whealin & Barnett, 2010). However, the role of disgust in the relationship between sexual trauma and female sexual dysfunction has not been examined. This study explored how disgust and a history of sexual trauma related to different domains of sexual functioning (desire, arousal, lubrication, orgasm, satisfaction, and pain). Furthermore, this study assessed whether disgust mediated …

Physiochemical And Nanomanipulation Studies Of Carbon Nanomaterials, Siva Naga Sandeep Chalamalasetty

Graduate Theses and Dissertations

Carbon nanomaterials are, without a doubt, one of man's wonder creations. Though these nanomaterials are a very recent trend, extraordinary electromechanical properties and the light weightiness of these nanomaterials attracted the attention of researchers. Although vast research has been done since the start of the US nanotechnology initiative, much effort was in the area of synthesis and characterization of the nanomaterials. However, most of the traditional macroscopic material's theories fail at the nanoscale level, and since the material properties are dependent on size and structure at nanoscale level, the behavior of the carbon nanomaterials in different environments needs attention. High …

An Alternate Approach To Ecosystem Mapping: Fusing Orthophotography With Landsat Etm+ Data For A Object-Based Classification, South Eastern Arkansas., David Mcfee

Graduate Theses and Dissertations

Maintaining representative sampling of biologically rich and rare ecosystems has become an important means to preventing biodiversity loss. A limitation in indentifying and quantifying ecosystems is the cost of obtaining high resolution imagery necessary for a high resolution land cover assessment. This research shows how free, different resolution imagery (orthoimages and LANDSAT ETM+) could be combined to produce a hybrid dataset with enhanced spectral, spectral and temporal properties, and processed to obtain a object-based classification of land cover of bottomland and pine hardwood forest in south eastern Arkansas. Three classification techniques were evaluated: 1) a human derived, rule based method, …

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 …

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 …

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 …

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 …

Arkansas Teacher Licensure Cut Scores, Do They Indicate Highly Qualified Teachers?, Karen K. Morton

Graduate Theses and Dissertations

The highly qualified provision of the 2001 No Child Left Behind Act promoted licensure exams on a national level. The present study is an effort to explore the most commonly used Praxis licensure exams and their passing scores. Hypothesized was that passing scores are set at such a minimal level that they are ineffectual in identifying highly qualified teachers. More specifically, Arkansas's low passing scores are examined by comparing the distribution of University of Arkansas Praxis scores to national trends. Based on low passing scores, the question was posed - At what point in teachers' careers are expectations lessened? Academic …

Determining Multidimensional Gender: Development And Psychometrics Of A Measurement Instrument, Karyl Lounsbery

Graduate Theses and Dissertations

Gender identity is often thought of only as a binary construct, masculine and feminine, despite the fact that there are many people who do not see themselves as fitting this dichotomy (Rochman, 2006). Within the counseling field, it is likely that every counselor will eventually see someone who will be struggling with issues of gender identity (Ehrensaft, 2011). The introduction of the Arkansas Multidimensional Gender Scale (AMGS) will show there is a much broader scope of gender identity, more in line with the idea that all gender identities are normal and that there are as many gender identities as there …

Children's Effortful Control In A Montessori Classroom: Effects Of Parenting And Purposeful Work, Judith Sarah Blahut

Graduate Theses and Dissertations

Research in effortful control is necessary to understand and support children's behaviors in Social and classroom settings (Rimm-Kaufman, Curby, Grimm, Brock, & Nathanson, 2009). This study reviewed literature discussing the relationship between parenting style and effortful control and Montessori philosophy as it relates to the work in practical life. The literature reviewed in this study suggested that parenting style may also be related to a child's effortful control. In addition, it was expected that the work of practical life in a Montessori classroom would positively influence effortful control in children. Using an experimental design, this study examined the efficacy of …

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 …

Modeling Water Stability And Transport On Mars And Iapetus: Exploring Their Effects On Geomorphic And Atmospheric Processes, Edgard Giovanni Rivera-Valentin

Graduate Theses and Dissertations

The stability and transport of water on solid planetary surfaces strongly affects both atmospheric and surfaces processes. In this work, two bodies are specifically investigated where transport of water is relevant: Iapetus and Mars. Iapetus, an icy Kronian satellite, has a drastic albedo contrast on its surface and one of the darkest surfaces in the solar system. This extreme brightness contrast is suggested to occur via the transport of water ice from the leading hemisphere to the trailing hemisphere and the poles. Here a global heat and mass transfer model is developed for Iapetus in order to study the current …

A Typology Of Preadolescent Sexual Abusers Based On The Emerging Personality Patterns In The Millon Preadolescent Clinical Inventory, Sam Wallace

Graduate Theses and Dissertations

The purpose of this study was to develop a personality-based typology of preadolescents with sexual behavior problems based the Emerging Personality Patterns in the Millon Preadolescent Clinical Inventory (M-PACI, Millon et al., 2005). Grounding a typology in a theory driven personality system may offer clarity and specificity in understanding preadolescents with sexual behavior problems in a manner that has not yet been explored. A personality and theory driven typology could provide a more comprehensive framework for assessing and treating children who sexually abuse than any of the current taxonomic models.

The study used an ex post facto design with test …

The Truth Between The Teeth: An Analysis Of Interproximal Tooth Wear At The Ables Creek Cemetery, Amy Reynolds Warren

Graduate Theses and Dissertations

Current archaeological knowledge suggests that, by the Late Mississippian period, inhabitants of the southeastern United States had adopted maize agriculture and that maize was a key component of the normal diet. However, in some regions where wild food resources were easily attainable, there is evidence that the transition to agriculture was delayed or did not occur at all. This thesis examines Late Mississippian skeletal collections from two sites in eastern Arkansas, Ables Creek and Upper Nodena. Analysis of differences in interproximal tooth wear facet size and caries rates between the two populations reveals that the diets at these roughly contemporary …

The Self-Efficacy Beliefs Of Black Women Leaders In Fortune 500 Companies, Latonya R. Jackson

Graduate Theses and Dissertations

Black women are underrepresented in leadership positions within organizations. The extent to which self-efficacy influences the advancement potential of Black females is unknown. The purpose of this study was to examine the self-efficacy beliefs of black women in leadership positions and to determine how Black women leaders' careers are influenced by their self-efficacy beliefs. Participants for the study were determined using convenient random sampling. The objectives of this study were to determine the profile and level of self-efficacy, and leadership practices of participants based on tenure (length of time in a leadership position), age comparison and work experience (total number …

Divine Hiddenness And The Challenge Of Inculpable Nonbelief, Matthew R. Sokoloski

Graduate Theses and Dissertations

Divine hiddenness is the idea that God is in some sense hidden or obscure. This dissertation responds to J.L. Schellenberg's argument, based on divine hiddenness and human reason, against the existence of God. Schellenberg argues that if a perfectly loving God exists, we would not expect to find such widespread nonbelief in God's existence. Given the amount of reasonable nonbelief in the world, Schellenberg argues that an agnostic ought to conclude that God does not exist rather than conclude that God is hidden. Schellenberg's argument has three major premises: (1) If there is a God, he is perfectly loving; (2) …

A 1,461-Year Growing Season Precipitation Reconstruction For The Carolina Coastal Plain, Kathryn Perkins Wolff

Graduate Theses and Dissertations

A recollection and dating of ancient cypress trees and subfossil logs was performed at Black River, North Carolina, and the separate Black River, South Carolina. The new updated and expanded chronologies date from AD 365 to 2010 and 549 to 2010, respectively. Baldcypress ring-width chronologies are dominated by high inter-annual to decadal variability and do not tend to capture century scale fluctuations in tree-ring growth that could be associated with centennial scale change in climate. The tree-ring chronologies were standardized with a technique designed to preserve low frequency variance known as regional curve standardization. The two chronologies were averaged into …

Perceived Impact Of Quality In A 21st Century Community Learning Center Out-Of-School Time Program: A Case Study, Patricia Ann Wright

Graduate Theses and Dissertations

Concern for the safety, education and well-being of children during out-of-school time is helping to change the landscape and priorities of families, educators and policy-makers. Changes in family structure and society have presented the need for quality out-of-school time programs. The changing family structure caused by both parents working outside the home, the advent of the single-parent household, the necessity of federally mandated standardized testing for student achievement, certain criminal activities and the expanding population of children have contributed to the question of how to protect children and enrich their lives during out-of-school time hours. The purpose of this intrinsic …

Happily Ever After Take Two: Rewriting Femininity In Hybridization Fairy Tale Films, Megan Estelle Troutman

Graduate Theses and Dissertations

The tradition of fairy tales has evolved drastically over the past five hundred years. At the beginning of the 20th century, fairy tale cartoons became widely popular as an independent medium, as well as introductions to larger films. In 1937, Walt Disney started the tradition of fairy tale cinema with the release of Snow White. Since that time, Disney has released and re-released eleven princess fairy tale films. Critics and parents alike ridicule Disney for its depictions of women as submissive and subservient. Recent films have used fairy tale tropes, without referring to a specific classic tale, in order to …

An Experimental Test Of Trauma-Relevant Cue Exposure And Desire For Alcohol Among Adolescents, Heidemarie Blumenthal

Graduate Theses and Dissertations

A burgeoning literature suggests a linkage between adolescent traumatic event exposure and problematic alcohol use. Research conducted with adults indicates that exposure to trauma-relevant cues elicits a desire to drink; however, no work has examined this association among adolescents. The current study was designed to build upon and extend this line of work. Participants were 72 community-recruited adolescents (Mage = 16.19; 34.7% girls). Trauma-exposed (n = 47) and non-exposed (n = 25) youth were assigned to either a 3-minute experimental (voluntary hyperventilation) or control task (low-arousal picture viewing). Desire to drink was assessed (1) prior to task assignment, and (2) …

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 …

Cotton Response To High Temperature Stress During Reproductive Development, Justin B. Phillips

Graduate Theses and Dissertations

Temperature is a primary controller of the rate of plant growth, developmental events, and fruit maturation. Increased temperatures from global climate change are projected to cause substantial losses in crop productivity by the end of the twenty-first century. Elevated temperatures affect all stages of cotton development, but the crop seems to be particularly sensitive to adverse temperatures during reproductive development. In Arkansas, temperature stress is considered to be one of the main factors affecting cotton yield. Environmental stress during floral development is a major reason for the disparity between actual and potential yields. Field and growth chamber studies were conducted …

Distribution And Control Of Herbicide-Resistant Italian Ryegrass (Lolium Perenne L. Ssp. Multiflorum Lam. Husnot) In Arkansas, James Walker Dickson

Graduate Theses and Dissertations

Italian ryegrass populations have evolved resistance to herbicides that producers rely on for weed control both in wheat and burn-down. The objectives of this research were to: test populations of Italian ryegrass from across Arkansas for resistance to glyphosate, diclofop, pinoxaden, and pyroxsulam; determine if there were any differences in control of 12 glyphosate-resistant populations in relation to glyphosate rate or application timing; determine the level of glyphosate resistance in one selected population versus a susceptible standard and a previously discovered glyphosate-resistant population; and determine the best options for controlling Italian ryegrass prior to planting crops. A total of 215 …

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 …

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. …

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% …

Colic In Infancy As An Indicator Of Subsequent Sensory Processing Development, Terri Anne Pohlenz

Graduate Theses and Dissertations

This paper attempted to find a link between infantile colic and subsequent sensory processing development. Literature research turned up very few studies linking colic with later development of sensory processing disorder. Ten hypotheses, based on literature research, linked colic in the first year with later indications of sensory processing disorder, whether formally diagnosed or anecdotally reported. None of the 10 hypotheses were proven.

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, …