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In Vivo Structure-Function Analysis Of Drosophila Robo1, An Axon Guidance Receptor Critical For Midline Repulsive Signaling In The Embryonic Central Nervous System, Haley Brown

Graduate Theses and Dissertations

The repellant ligand Slit and its Roundabout (Robo) family receptors regulate many aspects of axon guidance in bilaterians, including midline crossing of axons during development of the embryonic CNS. Slit proteins are produced by midline cells and signal through Robo receptors expressed on the surface of axonal growth cones to repel axons from the midline. Disruption of Slit-Robo signaling causes ectopic midline crossing phenotypes in the CNS of a broad range of animals, including insects and vertebrates.

Drosophila Robo1 has a conserved ectodomain structure of five immunoglobulin-like (Ig) domains plus three fibronectin (FN) repeats. By utilizing a genomic rescue construct …

Transformational Leadership In Club Sports: An Instrument For Evaluation And Assessment, Nathan Shelby Hutchens

Graduate Theses and Dissertations

Campus Recreation and its programs can be used as a way to combat the national trends of decreasing enrollment and retention (Weaver, Forte, & McFadden, 2017; Kampf & Teske, 2013). In fact, 62% of students indicate that Campus Recreation programs are a factor when choosing an institution and 67% indicate that recreation programs were a factor when deciding to stay at a particular institution (Forrester, 2014). As a program within Campus Recreation, Club Sports specifically is perceived to have the greatest health and wellbeing benefits out of all Campus Recreation programming (Lower, Turner, & Petersen, 2013). Due to the voluntary …

The Effect Of Cellular Dehydration On Glucose Regulation In Lean And Obese Females, Chunbo Yang

Graduate Theses and Dissertations

A chronically elevated vasopressin level has been associated with an impaired glucose regulation system in humans. A recent study in patients with diabetes suggested that low water intake is associated with impaired glucose regulation. The aim of this study was to examine the effect of hypertonic saline infusion on glucose regulation in healthy females. Thirty healthy, non-diabetic females performed a 2-h infusion followed by a 4-h oral glucose tolerance test (OGTT). Every subject participated in two trials separated by one month, in a counterbalanced order. Two trials were identical in the procedure, differing in the concentration of saline infusion, with …

Evaluation Of The Effects Of Formaldehyde On Growth Parameters Of Broiler Chicks, Paula Johnson

Graduate Theses and Dissertations

Formaldehyde has been used as a disinfectant in poultry hatching cabinets to aid in controlling key pathogenic organisms, such as Salmonella and Escherichia coli (E.coli). There is some evidence that prolonged exposure of chicks to formaldehyde can reduce tracheal ciliary function and thus reasons to believe that exposure to formaldehyde, in the absence of pathogen challenge, may reduce chick vitality. It has been found that elevated temperatures during incubation may adversely affect body weights of broiler chicks, as well as post-hatch environmental heat stress on performance in poultry. Post-hatch environmental heat stress has been shown to impact performance in poultry. …

The End Of Want, Anthony Blake

Graduate Theses and Dissertations

The poems of The End of Want are attuned to the absurdities of modern existence. They take as their jumping-off points the various offbeat occasions that punctuate our lives: over-researched time spent in art museums, Kevin James sitcoms, half-finished cathedrals, and suburban communal living. They catalog the emptiness of what we say to each other and the increasingly disconnected ways we say it. All the while, with dry humor and heart, they search out, and try to hold onto, moments of transcendence amongst corporate language and new definitions of masculinity, and humanity, and holiness.

The Vaginal Microbiome Related To Reproductive Traits In Beef Heifers, Maryanna Wells Mcclure

Graduate Theses and Dissertations

The greatest impact on profitability of a commercial beef operation is reproduction. In the human vaginal microbiome, dominance by Lactobacillus is a sign of reproductive health and fitness. In other species (non-human primates and ewes), Lactobacillus is found in low amounts and dominators of these microbial communities are considered to be pathogenic in humans. In beef heifers, little is known about the vaginal and fecal microbiota with respect to their relationship with fertility. To this end, we followed heifers through gestation to examine the dynamics of vaginal and fecal microbial composition throughout pregnancy.

Heifers were exposed to an estrus synchronization …

“The Commercial Union Of The Three Americas:” Major Edward A. Burke And Transnational New South Visionaries, 1870-1928, Michael Powers

Graduate Theses and Dissertations

Traditional images of the late nineteenth and early twentieth-century American South are of an inward-looking region characterized by economic stagnation, xenophobia, cultural isolation, and reactionary politics. This dissertation contends that vibrant transnational links connected the South to the wider world through an analysis of the political and economic landscape of postbellum Louisiana, the 1884 New Orleans World’s Industrial and Cotton Centennial, the Louisiana State Lottery Company, and Central America. An examination of Edward Austin Burke demonstrates that the era’s New South creed comprised a seminal transnational component.

This dissertation will explore how Burke became a central cog in Louisiana’s Democratic …

Jarfly, Zachary Harrod

Graduate Theses and Dissertations

To look, through poetry, at the men my culture has produced. Formal decisions are unique to each poem which are arranged sonnets, couplets, quatrains, among other forms and free verse forms. Toxic masculinity is examined, as well as the people enabled, participating in, and victimized by that culture.

Computational Fluid Dynamics Model For Air Velocity Through A Poultry Transport Trailer In A Holding Shed, Christian Heymsfield

Graduate Theses and Dissertations

Broiler production in Arkansas was valued at over $3.6 billion in 2013 (University of Arkansas Division of Agriculture Cooperative Extension Service). Consequently, improvement in any phase of the production process can have significant economic impact and animal welfare implications. One area of concern for the poultry industry is thermal stress experienced by the birds after arrival at the processing plant and before they are taken in to be processed, during which time they are left to wait in holding sheds. Various cooling strategies exist to mitigate heat stress in holding sheds, but in most cases it is unlikely that they …

Defending Wild Dogs: Population Dynamics And Disease In Endangered African Wild Dogs, Elizabeth Claire Arredondo

Graduate Theses and Dissertations

African wild dogs (Lycaon pictus) are endangered carnivores whose population is decreasing from habitat loss and fragmentation, interspecific competition, and disease. Survival rates are especially low in Kruger National Park (KNP), though it is unclear why. I estimated the abundance in KNP and survival rates over different time spans, six years and nine months, using public photographic survey data. In 2015, there were 298 (SE=12.1) individuals. Using a mark-recapture analysis in program R, I found that the survival rate between 2009-2015 was only 3.2%, and within the 9-month survey period (September 2014 – June 2015), monthly survival rates for the …

Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling, John A. Handley

Graduate Theses and Dissertations

The United States poultry industry generated 38.6 billion pounds (17,500 metric ton) of meat in 2014 which averaged to 121 pounds (55 kg) per individual of the U.S that same year. Of that meat generated by the poultry industry, an estimated 1 million cases of Salmonellosis will occur. Out of the 1 million cases approximately 40, 000 to 50,000 will be confirmed cases by the CDC. Recently, the USDA has requested changes in the inspection process and are currently allowing processors more freedom to utilize innovation to drive the increase in safer and more desirable foods. The new standards set …

Unravelling The Layers Of Cell Wall Synthesis And Function In Rice, Ritu Mihani

Graduate Theses and Dissertations

The plant cell wall is of critical importance to plant growth and survival, functioning in maintaining structural integrity, supporting cell expansion, and acting as the first line of defense in response to biotic and abiotic stresses. The major components of the cell wall are cellulose, hemicelluloses, lignin, and pectin. Recent focus on the transcriptional machinery regulating cell wall biosynthesis in plants has revealed many key transcription factors responsible for orchestrating cell wall deposition. However, many of these TFs act redundantly and work coherently with a suite of TFs to activate the cell wall biosynthetic machinery. Heterologous expression of TFs is …

Combining Translational And Functional Genomic Approaches To Augment Management Strategies Of Plant Parasitic Nematodes, Sandeep Sharma Khatiwada

Graduate Theses and Dissertations

Plant-parasitic nematodes pose a major threat to crop yield worldwide. Discontinued use of harmful chemicals has prompted the search for alternative management strategies that are effective yet environmentally friendly. Harpin proteins, which are derived from bacteria, and nematophagous fungi, natural predators of nematodes, are ideal for biological control of plant-parasitic nematodes. However, research on the efficacy of harpin proteins on nematodes, and biology of nematophagous fungi is minimal. Previously, a taxonomically uncharacterized nematophagous fungus designated ARF18 effectively suppressed nematode populations in soil. The overarching goal of this dissertation is to utilize applied and functional genomic approaches to augment management of …

Sacral Morphology Of Prehensile-Tailed Primates In Relation To Biomechanical Loading, Hannah Grace Showalter

Graduate Theses and Dissertations

The few available comparative studies of prehensile tail anatomy in primates have established that several features of the caudal vertebrae are associated with adaptation to the increased loading of the tail during prehension. Given that the caudal vertebrae are anchored to the sacrum, it stands to reason that sacral morphology should also covary with tail prehensility. Convergent evolution of prehension in ateline and cebine primates and clear variation in the use of tails among taxa raises questions not only of how sacral morphology differs between prehensile and non-prehensile taxa, but whether different prehensile-tailed taxa evolved the same solutions to the …

A Comparison Of Craniofacial Asymmetry In Gorilla Gorilla Gorilla And Pan Troglodytes Troglodytes, Ashly Noel Romero

Graduate Theses and Dissertations

Fluctuating asymmetry (FA) – random deviations from bilateral symmetry in an organism’s paired features – is a good candidate for investigating developmental stability. This easily accessible measurement can be used to understand the relationship between stress and development across organisms, and growth rate plays a vital role in developmental processes. Few studies have investigated craniofacial FA in non-human primates, and those that have suggest that levels of FA are higher in slower growing species. This study examines craniofacial FA in two primate species (Pan troglodytes troglodytes and Gorilla gorilla gorilla; n=81) to elucidate the effect of growth rate on FA …

Multiscale Investigation Of The Behavior Of Heart Valve Interstitial Cells In Response To Pathological Shape And Mechanical Stimulation, Ngoc Thien Lam

Graduate Theses and Dissertations

Our works aim to provide an insight into how aortic valve interstitial cells (VICs) respond to pathological shape and mechanical stimulation as well as the potential signaling pathway that mediates these responses, using a multiscale approach. A single cell model was developed to investigate the effect of altered shape on valve cell function as valve cells were reported to significantly deform during the cardiac cycle. Single VICs were controlled to take on features with different width-to-length aspect ratios that corresponded to the steady-state shapes adopted by VICs when stretched to 0%, 10% and 20%, respectively. It appeared that single VIC …

Rapid And Sensitive Detection Of Escherichia Coli O157:H7 Using A Qcm Sensor Based On Aptamers Selected By Whole-Bacterium Selex And A Multivalent Aptamer System, Xiaofan Yu

Graduate Theses and Dissertations

Escherichia coli O157:H7 is one of the top five pathogens contributing to foodborne diseases, causing an estimated 2,138 cases of hospitalization in the US each year. The extremely low infectious dose demands for more rapid and sensitive methods to detect E. coli O157:H7. The objective of this study is to select aptamers specifically binding to E. coli O157:H7 using whole-bacterium SELEX (Systematic Evolution of Ligands by Exponential Enrichment) and to create a multivalent aptamer system by rolling circle amplification (RCA) with the selected aptamer sequence for sensitive detection of E. coli O157:H7 using a quartz crystal microbalance (QCM) sensor. Briefly, …

Preservice Agricultural Education Teachers And Secondary Education Teachers’ Self-Efficacy And Professional Identity, Hailey Gates

Graduate Theses and Dissertations

During the nineteenth century, a decision was made to separate the preparation of agricultural education teachers from their elementary and secondary counterparts (Hearings, 1908; Heren & Hillison, 1996; Hillison, 1986). The majority of land-grant universities and colleges have continued to prepare agricultural education preservice teachers within the college of agriculture, separate from other secondary education preservice teachers in the college of education (Myers & Dyer, 2004). Despite the differences among content disciplines, teachers who possess a strong sense of self-efficacy and professional identity have higher success rates in the classroom when it comes to collaboration, involvement, and student achievement (Ashton …

Examination Of Shape Variation Of The Calcaneus, Navicular, And Talus In Homo Sapiens, Gorilla Gorilla, And Pan Troglodytes, Nicole Lynn Robinson

Graduate Theses and Dissertations

Analyses of morphological integration among primates commonly focus on relationships between the face, braincase and base of the skull, as well as the upper and lower dentition, and the within portions of the post-cranial skeleton. Despite the prominence of these studies, the associations between the bones of the foot and their articular surfaces have largely been ignored among primates, even though the foot demonstrates high degrees of variation and modification. This variation offers an ideal opportunity to study the relationship between morphology and locomotion. Because the talus, calcaneus and navicular act together to stabilize the foot in locomotion and form …

The Myth Of Southern Atonement: Constructed Forgiveness In Public Spaces, Elizabeth Ashley Clayborn

Graduate Theses and Dissertations

This thesis provides a rhetorical analysis of public space in Arkansas and examines the ways in which the myth of Southern Atonement is constructed within those spaces. Three formal elements characterize Southern Atonement: absolution from the past, distinctiveness in constructed authenticity, and hope for a post-racial future. The analysis develops over three case studies which I argue contribute to the construction, engagement, and actualization of this cultural myth. The first chapter looks at Fort Smith, Arkansas, and The Unexpected art project as a source of identity construction and place attachment. Then I examine The Billgrimage, or the monuments and museums …

Species And Cultural Management Of Earthworms On Golf Course Turf In Arkansas And Oklahoma, Paige Elizabeth Boyle

Graduate Theses and Dissertations

As earthworms feed, they can egest soil and nutrient-rich aggregates (casts) on the soil surface. In low-cut turfgrass systems, such as golf course greens, tees, and fairways, surface casting can result in a muddy playing surface, ball roll issues, weed and pest invasion, reduced aesthetics, surface softening, and reduced photosynthesis. Because the use of pesticides for earthworm control is illegal in the U.S., earthworm casting must be managed through cultural practices. Sand topdressing is one method of earthworm control studied for use on golf courses, with the supposition being that the abrasive sand particles will deter the soft-bodied earthworms from …

Formal Learning In An Informal Setting: The Cognitive And Affective Impacts Of Visiting A Science Center During A School Field Trip, Charlie Belin

Graduate Theses and Dissertations

With the pressures of budget cuts, many schools--particularly schools serving low-income students--are eliminating school field trips to museums, zoos, and other cultural institutions despite their widely reported utility. First, through a systematic review of the literature, I examine the findings from 17 international studies on the benefits of visiting an informal science education institution during a K-12 school field trip. Almost all pre-post studies reported a positive change in both cognitive and affective outcomes after visiting an ISEI. However, studies that also included a control group to compare students who visited the ISEI with students who had yet to visit …

Gothic Voids: Nineteenth-Century Reader Experience And Participation, Garrett Chapman Jeter

Graduate Theses and Dissertations

Characterization of nineteenth-century literary Gothic is usually confined to affective response. This project argues that literary Gothic works constitute an intellectual, empirical endeavor. Because authors of literary Gothic intentionally left voids in their narratives, they invited their readers to participate in making narrative through speculation and conjecture about missing information. The practice of Gothic reading makes the reader an active partaker in filling those voids with rational conclusions. Reading is not just textual encounter. Rather, it incorporates making meaning of one’s surroundings. In their experiences, literary works’ characters “read” their environments: people, objects, events, etc. Chapter 1 characterizes Gothic reading …

Combining Microdialysis And Electrophysiology In Cerebral Cortex To Delineate Functional Implications Of Acetylcholine Gradients, Tazima Nur

Graduate Theses and Dissertations

The neuronal network in cerebral cortex is a dynamic system that can undergo changes in collective neural activity as the organism changes its behavior. For example, during sleep and quiet restful awake state, many neurons tend to fire together in synchrony. In contrast, during alert awake states, firing patterns of neurons tend to be more asynchronous, firing more independently. These changes in population-level synchrony are defined as changes in cortical state. Response to sensory input is state-dependent, i.e., change in cortical state can impact the sensory information processing in cortex and introduce trial-to-trial variability in response to the same repeated …

Towards Quantifying Relevant Land Cover Change: A Case Study In The Central Flyway Of The Monarch Butterfly, Hanna Lenee Ford

Graduate Theses and Dissertations

Over the past 20 years notable decreases in monarch butterfly populations have led researchers to begin evaluating the landscape for changes and seeking out opportunities for enacting conservation programs to better support their survival. The monarch butterfly has recently come under consideration for listing under the Endangered Species Act which has created a need for a more informed view of the landscape through which the migrate and breed, the central United States. In this research three spatially-explicit models are explored using the most applicable datasets currently available to address pressing policy and land manager decisions regarding monarch butterfly and pollinator …

Evaluation Of The Efficacy Of A Candidate Turkey Dermatitis/Cellulitis Oil Emulsion Vaccine On Immune Response, Morbidity, And Mortality Under Laboratory And Commercial Conditions, Brittany Danielle Graham

Graduate Theses and Dissertations

Alpha-toxigenic Clostridium septicum (CS), the cause of turkey cellulitis, results in devastating mortality with high costs for the industry. Various vaccinations have been evaluated to prevent this disease with moderate success. Ability of a CS bacterin-toxoid, in conjunction with adjuvants such as aluminum hydroxide, mannoslyated chitosan, or a water-in-oil Seppic Montanide 71 R VG adjuvant (OE) to induce immunity was evaluated in a 7-week study (Experiment 1). Poults (20/group) were vaccinated day-of-hatch, boosted at 5 weeks-of-age and compared to unvaccinated controls. Antibody titers were determined by ELISA for all experiments. In experiment 1, initial vaccination with OE resulted in significantly …

The Effect Of Napping On Sleep Quality And Quantity In Healthy And Concussed Collegiate Athletes, Katie Stephenson-Brown

Graduate Theses and Dissertations

Clinicians are increasingly prescribing a regulated sleep schedule to athletes post injury; however, baseline sleep habits of collegiate athletes are unknown. Moreover, the connection between napping and sleep quality and quantity has not been studied in collegiate athletes. Therefore, the purpose of this study is to investigate napping behaviors and their effects on sleep quantity and quality in concussed and non-concussed collegiate athletes. In a sample of 233 non-concussed collegiate athletes, 74% (172/233) of participants reported napping. Napping was not significantly associated with sleep quantity (χ 2 (2) = .23, p = .64) or quality (χ 2 (1) = .42, …

Behavior Coding Strategies: Population Coupling And The Functional Role Of Excitatory/Inhibitory Balance In Primary Motor Cortex, Patrick Aaron Kells

Graduate Theses and Dissertations

The complexities of an organism’s experience of- and interaction with the world are emergent phenomena produced by large populations of neurons within the cerebral cortex and other brain regions. The network dynamics of these populations have been shown to be sometimes synchronous, with many neurons firing together, and sometimes asynchronous, with neurons firing more independently, leading to a decades-old debate within the neuroscience community. This discrepancy comes from viewing the system at two different scales; at the single cell level, the spiking activity of two neurons within cortex tend to be rather independent, but when the average activity of a …

Seasonal Phenology, Distribution And Treatments For Polyphagotarsonemus Latus (Banks) On Primocane-Fruiting Blackberries (Rubus L. Subgenus Rubus) In Arkansas, Jessica Anne Lefors

Graduate Theses and Dissertations

Worldwide, blackberries (Rubus L. subgenus Rubus) are an economically important crop. In 2007, Polyphagotarsonemus latus (Banks) (broad mites), were first reported damaging primocane-fruiting blackberries in Fayetteville, Arkansas. Since this time, broad mite damage to blackberries and yield loss has been reported in many states and countries. Despite the increasing reports of this blackberry pest, little is known about their population dynamics, and few treatments are available. Growers with broad mite populations need a pest management program to minimize yield loss. Therefore, there was a need to develop sampling techniques, describe broad mite seasonal phenology in blackberry fields, and determine efficacy …

Immunostimulatory Effects Of Antigen-Conjugated Inp/Zns Quantum Dot Nanoparticles In An Avian Model, Christopher Lyle

Graduate Theses and Dissertations

Due to their unique physicochemical and enhanced immunostimulatory properties, quantum dot (QD) nanoparticles have shown increasing promise in biomedical research applications including bioimaging, drug delivery, and as vaccine adjuvants. Toxicity, however, remains a concern for the use of QD in these applications and thus, there is an increased demand for effective in vitro and in vivo systems to measure the bioactivity of QD. In this study in vitro and in vivo chicken models were used to investigate the effects of QD on innate and adaptive immunity. Chicken macrophage cultures were treated in vitro with QD to measure macrophage activation and …