Life Sciences Commons^™

Cannabinoids Suppress The Innate Immune Response To Periodontal Pathogen Porphyromonas Gingivalis In Gingival Epithelial Cells., Rajarshi Guha Niyogi

Electronic Theses and Dissertations

Marijuana is widely used in the United States for recreational and medicinal purposes. Despite the proposed beneficial effects of cannabis on certain medical conditions, there is also a concern there is also a concern over negative health consequences of marijuana smoking. Recently, cannabis use has been established as a dose related risk factor for chronic periodontitis. Although the induction / exacerbation of chronic periodontitis in marijuana users has been established epidemiologically, the mechanisms underlying such predisposition are still unknown. It has long been suggested that marijuana has anti-inflammatory properties, while human epithelial cells are known to express cannabinoid receptor type …

Cardiovascular And Hematopoietic Responses To Volatile Benzene Exposure., Wesley Tyler Abplanalp

Electronic Theses and Dissertations

The rapid and recent increase in the global epidemic of diabetes and cardiovascular disease suggests a strong component of the environment is contributing. Benzene is a ubiquitous volatile pollutant generated by cigarette smoke, automobile exhaust, wildfires and industrial activities. Consequently, it is found in almost all urban and rural air samples. Benzene is known to cause hematotoxicity and its metabolism generates oxidative stress. Although, benzene has been studied for many years, few investigations have probed what influence benzene exposure may have on other physiological processes. Here we hypothesize that benzene metabolism by hepatic-CYP450 2E1 generates oxidative stress and inflammation, which …

Effect Of Migration, Carrying Capacity, And Fecundity On The Formation Of Clinal Patterns During Range Expansions., Neha J. Angal

Electronic Theses and Dissertations

Range expansions, empirically and in simulations, lead to clinal patterns of genetic diversity. Clines are often used as spatial markers of past migrations. This study investigated the effects of migration, growth, and carrying capacities on clinal patterns during range expansions, using forward-time simulations in Nemo. Initial results show, in the absence of prior population structure, range expansions result in a loss of diversity strongly affected by migration, growth, and carrying capacity. This loss of diversity did not persist to the final generation, corresponding to 10,000 years, indicating clinal patterns are less durable than previously assumed—challenging the utility of clinal patterns …

Isolation Of Egfr-Containing Early Endosomes., Julie A. Gosney

Electronic Theses and Dissertations

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) that is an integral component of proliferative signaling. When activated by a ligand at the plasma membrane, EGFR undergoes clathrin-mediated endocytosis. This spatial regulation of the receptor is an important regulator of receptor expression as it mediates its degradation. Endocytosis also has implications on EGFR downstream signaling, though the details are not fully understood. The goal of this thesis is to develop a method to isolate early endosomes in order to study downstream effectors associated with activated EGFR in this compartment. HeLa cells were used to test various …

Impact Of Luminance And Spatial Parameters On The Generation Of The Human Pattern Electroretinogram., Kate A. Godwin

Electronic Theses and Dissertations

The current work assessed some of the key hypotheses behind the generation of the pattern electroretinogram (PERG) response. The first of these hypotheses states that the PERG response is the result of linear cancellation of simultaneous increment and decrement retinal responses, as generated by the retinal ON- and OFF-pathways. Experiment 1 evaluated the possibility of simulating the PERG by summing the ERG responses elicited by increment and decrement flashes, and found that it was indeed possible to simulate the PERG from these responses. However, only the steady-state PERG could be modeled consistently. The second hypothesis evaluated a theory that the …

Effects Of Neonatal Capsaicin On Formalin-Induced Atf3 Expression In The Adult Rat., Sarah Krupp

Electronic Theses and Dissertations

Acute and chronic pain can be extremely debilitating conditions, and a better understanding of their underlying pathology is necessary to provide effective treatment. C-Fibers are responsible for transmission of the majority of nociceptive signals, with TRPV1+ C-Fibers being specific to noxious heat. Formalin, an inflammatory agent, acts through TRPA1+ C-Fibers, which have a high degree of co-localization with TRPV1. Using a neonatal capsaicin preparation, which irreversibly ablates the majority of TRPV1+ C-Fibers, formalin- induced inflammation and subsequent ATF3 expression was investigated. Results provide evidence that in addition to a lack of thermal nociception, animals treated with neonatal capsaicin had a …

A Systems Biology Approach Identifies A Gene Regulatory Network In Parotid Acinar Cell Differentiation., Melissa Ann Metzler

Electronic Theses and Dissertations

Objective: This project sought to understand the gene regulatory networks that drive parotid salivary gland acinar cells to terminally differentiate, and drive expression of terminal differentiation genes in dedifferentiated ParC5 cells. Methodology: Laser capture microdissection was used to isolate acinar cells at multiple time points during differentiation. This important step allowed us to measure gene expression in a single and important cell type. A systems biology approach was taken to measure global mRNA and microRNA expression across acinar cell terminal differentiation in the rat parotid salivary gland. In ParC5 cells, the ER stress activator tunicamycin was used to stimulate Xbp1 …

The Role Of The Nucleolus In Neurodegeneration., Justin Lauren Hallgren

Electronic Theses and Dissertations

The overarching goal of my studies was to determine the role of the nucleolus in neurodegenerative disease. Numerous studies suggest the impairment of ribosomal biogenesis in neurodegenerative disease and such a condition may contribute to neuronal dysfunction in two ways, loss of function and stress response. Ribosomal biogenesis has been demonstrated to play an essential role in both neuronal growth and maintenance. Therefore insufficient levels of ribosomal biogenesis would be expected to produce atrophy and synapse loss. Moreover, the fidelity of ribosomal biogenesis is monitored by nucleolar and ribosomal stress responses which induce apoptosis and/or cell cycle arrest. Therefore, I …

Experimental Assessment Of Floating Seagrass Wrack As Potential Habitat For Benthic Organisms, Joseph R. Mcginnis

Theses, Dissertations and Culminating Projects

During the summer, seagrass blades are frequently released into the water column as a method to reduce respiration demands of the plant and through physical disruption of the bed (e.g., crab foraging, boat propellers). This wrack has the potential to serve as both food and habitat for organisms dislodged or actively moving within the system. The purpose of this research was to determine how benthic organisms may use floating wrack as a food resource and shelter. Three experimental floating wrack bag treatments were assembled containing using artificial Zoster a marina (i.e., poly-ribbon), Z. marina blades, and a wrack bag control …

Assessment Of The Level Of Protection Against Coccidiosis In Broiler Breeders Conferred By A Live Anticoccidial Vaccine, And Its Influence On Early Growth And Development., Muhammed Shameer Abdul Rasheed

Graduate Theses and Dissertations

Coccidiosis continues to be a great challenge to the poultry industry all over the world and in broiler breeders vaccination with live oocysts of Eimeria has been widely adopted as a control measure. Broiler breeders are usually subjected to feed restriction during their early growth however no studies have been undertaken on the effects of vaccination in birds whose feed has been restricted in this manner. The objective of this study was to assess the level of protection acquired by broiler breeder chickens when immunized at day-old with live eimerian oocysts and given a restricted diet. Effects upon growth and …

Effect Of Hydration Status On Thermoregulatory Responses In Non-Obese And Obese Males, Matthew Tucker

Graduate Theses and Dissertations

During heat stress the human body thermoregulates via cutaneous vasodilation and sweating. Hypohydration can impair thermoregulatory responses that stem from the central nervous system (CNS), but it is unknown if impairments also occur post-synaptically in the microcirculation. Moreover, obese individuals may have impaired thermoregulation, possibly due to microvascular dysfunction. Purpose: The purpose of these studies was two-fold: 1) to determine if obese (OB) individuals exhibit impairments in thermoregulatory responses during exercise heat-stress (centrally-mediated) and intradermal infusion of vasoactive substances (peripherally-mediated) versus non-obese (N-OB), and 2) to determine if hypohydration subsequently affects these thermoregulatory responses differently between groups. Methods: Twenty-one healthy, …

Characterization Of Broiler Lines Divergently Selected For Breast Muscle Color, Sara Katherine Orlowski

Graduate Theses and Dissertations

An increase in the consumption of poultry has generated an increase in demand for higher yielding broilers. This has led to an increase in atypical meat and issues with appearance. Color is a direct result of a pH decline as meat goes through rigor mortis with meat generally becoming lighter. If the pH declines too rapidly or too slowly, meat quality can suffer. Physical properties of meat can be altered by pH. A fast pH decline results in pale meat with decreased tenderness. A slow pH decline can result in darker meat with a reduced shelf-life. With a known relationship …

In Vitro Fermentation Patterns Of Rice Bran Components By Human Gut Microbiota, Tung Minh Pham

Graduate Theses and Dissertations

The prevalence of colorectal cancer (CRC) has been increasing in recent years worldwide. In the United States, it is ranked the second leading cause of cancer death. Risks of CRC increase with age and are associated with several lifestyle factors such as diet, drinking and smoking habits, and levels of physical activity. There is an abundance of scientific literature demonstrating the protective roles of several dietary components including fibers and polyphenolic compounds. These compounds have been shown to be able to positively modulate gastrointestinal ecology by increasing the production of short-chain fatty acids (SCFA) and promoting the population of beneficial …

Mental Toughness, Grit, And Motivational Differences In Single-Sport And Multi-Sport Athletes, Cole Justin Shewmake

Graduate Theses and Dissertations

Whether it is at work, school or sports, mental toughness (MT), grit and motivation are essential to accomplishing goals. Sports can be an integral platform for developing MT, grit, and factors that increase motivation levels, and it is during childhood and adolescence that these characteristics may develop. All of this could prove beneficial into adulthood. Therefore, the purpose of this study was to examine MT, grit and motivational orientations of single-sport and multi-sport athletes at different levels of competition. Considering MT, a 2 x 2 ANOVA indicated no significant interaction effect between athlete type and competition level, F(1, 387) = …

Two-Electron Quenching Of Dinuclear Ruthenium(Ii) Polypyridyl Complexes, Yinling Zhang

Graduate Theses and Dissertations

A bridging ligand 5,5’-Bi- 1,10-phenanthroline, diphen, was prepared using dichlorobis(triphenylphosphine)Ni(II), Ni(PPh3)2Cl2 as catalyst with a yield of 40%. Yellow cubic crystals were able to obtain from the good purity product for single crystal analysis. The torsion angle between the planes of the subunit phenanthrolines is about 66 degrees.

A dinuclear ruthenium (II) polypyridyl complex, (phen)2Ru(diphen)Ru(phen)24+, was synthesized by using polymeric ruthenium carbonyl compound as the entry point, diphen as the bridging ligand and 1,10-phenanthroline, phen, as the terminal legand. Brown needlelike crystals were precipitated from acetonitrile that were not suitable for single crystal diffraction.

The photochemistry of the dimer was …

Comparisons Of Selected Household And Commercial Disinfectants Against Poultry Salmonella Isolates And A Survey Of Internal Parasites In Backyard Poultry In Arkansas, Kayleigh Moyle

Graduate Theses and Dissertations

Backyard and exhibition poultry have been gaining in popularity and as such there has been a large increase in the number of small flocks. As the interaction with poultry has increased, so has the opportunity for diseases and parasites, for both birds and people. One of the major zoonotic illnesses is caused by the bacteria Salmonella, which can be found in commercial and small flocks. Salmonella is the number 2 contributor of foodborne illnesses so its prevalence in commercial flocks is of high concern. Despite improved cleaning, disinfection, and biosecurity practices, there is still potential for disease outbreaks and infections …

Determination Of Optimum Fall And Spring Nitrogen Fertilizer Rate For Maximizing Grain Yield Of Soft Red Winter Wheat Sown At Variable Planting Dates, Lucas Vasconcelos Vieira

Graduate Theses and Dissertations

An optimum planting date is important for winter wheat nitrogen (N) management as it dramatically changes the growing environment including temperature and moisture, ultimately affecting fertilizer efficiency and grain yield (GY). In Arkansas, high precipitation in the fall often forces farmers to delay planting and current Arkansas recommendations include the application of fall N when soft red winter wheat (SRWW) is sown later than optimum, despite the lack of data supporting this practice. This study evaluated the effect of rate and timing of N application on GY of SRWW sown at variable planting dates in Arkansas. Granular urea was split …

Shifts In Myxomycete Community Structure In Selected Microhabitats Across Nutrient Treatments In A Lowland Tropical Forest Of Panama, Laura M. Walker

Graduate Theses and Dissertations

Myxomycetes (plasmodial slime molds) are abundant amoeboid predators of bacteria and other microorganisms. They are found worldwide, largely in association with decaying plant material in terrestrial habitats. Their consumption of bacterial prey puts microbial predators such as myxomycetes in a key position in various ecosystem processes wherein they help regulate the flow of nutrients (e.g., N and C) through the ecosystem. The importance of microbial predators in nutrient cycling and plant productivity is well established. Given the extent to which tropical ecosystems influence global nutrient fluxes, along with the ecologically significant role that myxomycetes play in these processes, there is …

Culinary Competence: Skills And Knowledge Assessment For Dietetic Students, Nancy Harris Buckley

Graduate Theses and Dissertations

Graduates of didactic programs in dietetics are entering internships with little cooking experience. The Food and Culinary Professionals’ Dietetic Practice Group (FCP DPG) has identified 11 core competencies that were developed as a recommendation to dietetic educators to include more culinary knowledge into existing programs. The purpose of this study was to determine if developing and incorporating experiential learning targeted to the competencies would increase dietetic students’ culinary skills and knowledge at a southern land-grant university. Food and Culinary Professionals’ DGP core competencies were used to guide the development of curriculum, experiential learning, and assessment in the Principles of Foods …

Investigation Of The Interaction Of Dimeric Ruthenium Complexes With Cytochrome B5, Christopher Dain Rupar

Graduate Theses and Dissertations

Photoreactive complexes to study the kinetics of electron transfer of proteins have been in use for a long time. It has always been speculated that complexes bind near the heme or the electron transfer reaction would not occur. But it is unkown exactly how the complex interacts with the protein. The structural, thermodynamic, and kinetic properties of rat liver microsomal cytochrome b5 were investigated when bound to ruthenium dimer complexes. Heteronuclear Single Quantum Coherence studies support a dynamic binding model of a dimer Ru complex bound near the protein’s heme involving residues H39, E44, G42, V61, G62, and H63. The …

The Cytotoxic And Antimicrobial Properties Of Pine Essential Oils: A Characterization And Comparison, Richard Sakul

Graduate Theses and Dissertations

In the forestry industry, the pine tree species are important because of their durable timber and fast growth. In Arkansas, trees such as the loblolly pine compose almost a third of the timberland, seven million acres. In addition to the lignocellulosic biomass, pine bark and needles potentially have industrial importance as a waste stream from which high value (e.g., pharmaceutical, cosmetics) chemicals could be extracted, which could potentially increase the profit margin of forestry operations. In this research, the possibility that pine needles harvested from industry processed pine tree residues could be used as an antibacterial or cytotoxic chemical agent …

Rice Consumption And Effects Of Rice Cake, Seolgitteok, On Human Health, Ellen Joy Pottgen

Graduate Theses and Dissertations

Within the United States type 2 diabetes is an ever growing health epidemic. The prevalence in the adult population has quadrupled over the past 30 years and is expected to continue on a similar path in the coming decades. While the cause of type 2 diabetes is multifactorial, it is considered to be an acquired condition related to environmental contributors including poor diet, obesity, and physical inactivity, which may be managed to alter the course or progression of the disease. Preventative or maintenance measures emphasize nutritional intervention strategies, including encouraging individuals to follow a nutrient-dense, high-fiber diet with ample whole-grains, …

Efficacy Of A Novel Intranasal Zinc Solution On The Microbiome, Health, And Growth Performance Of High-Risk, Newly Received Stocker Cattle, Makenzie Foster

Graduate Theses and Dissertations

The objective of this study was to determine if using an intranasal zinc (Zn) solution would impact health and growth performance of high-risk stocker cattle. Male beef calves (n = 239; 3 arrival dates [block]; initial BW = 276 ± 2.4 kg) were stratified by arrival gender and BW and assigned to 1 of 2 treatments: 1) treated with 3 ml of a Zn solution containing 36.24 mg of Zn administered intranasally, or 2) control, in which calves were not treated. Calves were observed daily and if exhibiting signs of morbidity and a rectal temperature ≥ 40° C they were …

Microbes In Rough Rice – Prevalence, Growth Kinetics And Links To Dry Matter Loss, Supriya Thote

Graduate Theses and Dissertations

The prevalence of microorganisms on freshly-harvested long-grain hybrid, long-grain pureline, and medium-grain rice has not been elucidated. The first objective of this two-part study was to determine the relative prevalence of microbes on freshly-harvested, high moisture content rice of different types and cultivars. The total and surface aerobic plate counts (APC) and mold counts were determined in terms of log10 colony forming units per gram of rice (log10 CFU/g) for six rice cultivars over two years. In 2013, among harvested samples of all the studied rice cultivars, the long-grain hybrid cultivars had the lowest APC levels (M = 8.10, SD …

Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson

Graduate Theses and Dissertations

In the past decade, 29 shale basins have been actively developed across 20 states for extraction of natural gas (NG) via horizontal drilling/hydraulic fracturing (=fracking). This includes ~5000 wells within the Fayetteville shale of north-central Arkansas. Development often impacts both river- and landscapes, and management requires catchment-level evaluations over time, with organismal presence/absence as indicators. For this study next-generation sequencing was used to identify/characterize microbial communities within biofilm of eight Arkansas River tributaries, so as to gauge potential catchment influences. Streams spanned a gradient of landscape features and hydrological flows, with four serving as ‘potentially impacted catchment zones’ (PICZ) and …

Observing Renal Responses To Endurance Cycling In The Heat, Cody Smith

Graduate Theses and Dissertations

AIM: To observe the effects of endurance cycling in the heat on renal function, and determine if the extent of impairment is related to hydration. METHODS: 40 cyclists (34 male, 6 female, 52 ± 9 y, 21.7 ± 6.5 % body fat) completed an endurance cycling event (5.7 ± 1.2 hours) in the heat (33.2 ± 5.0ºC, 38.4 ± 10.7% RH). Body mass was assessed to determine net fluid loss, muscle damage in the legs was assessed with a pain scale, a urine sample was collected to analyze hydration status, and a blood sample was drawn. All measurements were taken …

Age End-Point Effects On Performance, Carcass Measurements, And Tenderness In Goats, Kelsey Lynn Basinger

Graduate Theses and Dissertations

Goat meat is consumed all across the world, especially in developing countries. Moreover, the meat goat industry is growing in popularity in the United States due to ethnic demand of an increasing immigrant population. The objective of this study was to measure age end-point effects on performance, carcass measurements, and tenderness in goats. Intact Kiko × Boer F1 male (n = 46) kids were born on pasture in the spring of 2014 and 2015, weaned at approximately 100 d of age, and weighed monthly. Creep feed was offered to kids from birth to weaning and a high concentrate diet was …

High Throughput Phenotypic Evaluation Of Drought-Related Traits In Soybean, Hua Bai

Graduate Theses and Dissertations

Drought limits crop growth and yield in soybean. Rapid and effective methods of screening large numbers of soybean lines for drought tolerance are urgently needed. Two experiments were conducted to evaluate the effects of drought in soybean during reproductive stages. In the first experiment five genotypes from maturity groups 2 through 5 were tested under well-irrigated and drought conditions. Beginning at R5, leaf samples were taken for nitrogen concentration analysis. Pictures were taken across the top of each plot to determine the intensity of greenness using the Dark Green Color Index (DGCI). Aerial photographs were also taken to determine aerial …

Recognition Training For Faces Across Age Gaps, William Blake Erickson

Graduate Theses and Dissertations

Face recognition is a problem that has theoretical and applied value. However, the fact of facial aging is rarely addressed in research and unmentioned in the major theories of face recognition. Facial aging also has ramifications for missing persons and fugitive cases, confounding attempts by law enforcement to recover these people whose last known images are years or decades out of date. This dissertation reports three studies aimed at measuring baseline age-gap recognition ability and testing various training regimens designed to increase accuracy rates for this unique kind of recognition task.

Listeria Monocytogenes Strain Variation: Starvation, Metabolism, And Macrophage Survival, Nathan A. Jarvis

Graduate Theses and Dissertations

Listeria spp. are often isolated from raw and processed food products. Listeria monocytogenes is responsible for death rates of 10 to 30% in immune compromised people; it can also infect a vast range of animals. There are numerous reports of poultry harboring or becoming infected with L. monocytogenes. First, this research assessed the ability of L. monocytogenes to replicate within chicken macrophages. Using the gentamicin-killing assay, a cell culture of chicken macrophage-like cells (HD11) were infected with two strains of L. monocytogenes individually (EGD-e and Scott A). Results show that unlike data on mouse macrophages, intracellular L. monocytogenes do not …