Digital Commons Network^™

Identifying Leadership Perceptions Of Desired Competencies Of Agricultural Sales Students And Agricultural Sales Industry Professionals, Sarah Beann Wright

Graduate Theses and Dissertations

The two articles presented in this thesis used both quantitative and qualitative research methods to evaluate competencies among agricultural business students and agricultural sales professionals respectively. In the first study, students enrolled in the Fall 2014 agribusiness sales course at [State] University (n = 97), participated in a pre and post evaluation comprised of leadership assessments to determine the change in introversion and extroversion, task-oriented and relationship-oriented, and finally strength characteristics over the time period of an academic semester. Students presented to be from a variety of leadership backgrounds. Posttest results reported students being both high task (62.89%) and high …

Phenology And Diversity Of Arthropod Communities In Leaf Litter, Fredericka Hamilton

Graduate Theses and Dissertations

Temperate deciduous forests produce a layer of leaf litter on the forest floor annually. This layer is dynamic, and both the composition and depth change throughout the year. The leaf litter layer is an important habitat to many arthropods since they utilize it for food, shelter from adverse environmental conditions, and protection from predators.

Two commonly encountered and diverse taxa found in the litter layer are the ground beetles (Coleoptera: Carabidae) and the ground spiders (Araneae: Gnaphosidae). Carabidae and Gnaphosidae were collected and identified on a monthly basis from April 2014 to March 2015 from the Ozark Mountains of Arkansas …

Effect Of Feeding Regimen And Age On Lipid Metabolism In Broiler Breeder Hens And Progeny, Nirun Boonsinchai

Graduate Theses and Dissertations

Age of hens and feed allocation can affect egg yolk lipid compositions which in turn directly relate to chick quality. A series of experiments were conducted to determine the effects of age and feeding programs on lipid metabolism in breeder hens and progeny. In the first trial, the rate of yolk absorption and fatty acid profiles in the yolk were compared among 28, 35, and 49wk old hens. The results revealed that the rate of yolk absorption was higher, but the absolute amount of fatty acids absorbed was lower in young hens than in the old hens. The second trial …

Reducing Nutrient Runoff From Poultry Production Facilities Using Locally-Sourced Iron And Aluminum Byproducts, Sheri Lynn Herron

Graduate Theses and Dissertations

Phosphorus (P) inputs to fresh waters can accelerate the eutrophication process. Agricultural nutrient runoff has been shown to be a contributor of P and nitrogen (N). Broiler production areas were evaluated for their potential to contribute P and N to runoff. Broiler house dust (BHD) samples were analyzed and compared to broiler litter (BL), rainfall simulations were conducted on plots adjacent to broiler house fans to evaluate nutrient enrichment in runoff from deposited dust, and runoff was automatically sampled at two culverts draining the land around broiler houses. Following this, an on-farm byproduct containment and nutrient removal structure was designed …

Grass Finishing Systems For Lambs, Erin Leigh Smyth

Graduate Theses and Dissertations

There is strong interest in sustainably produced meat. Grass-fed lamb could fulfill this market by reducing off-farm inputs. The objective was to examine the effect of grass-finishing or minimal supplementation on performance of lambs in the southeastern US. Katahdin lambs born in October 2013 and 2014 and February 2014 were weaned in January 2014/2015 and May 2014, respectively. Lambs were blocked by gender (fall; winter included only ram lambs) and randomly assigned to receive no (NON) or grain co-product supplement (SUP; 15% CP) at 0.5% of BW/d. Lambs were rotationally grazed on predominantly grass. Body weight, fecal egg counts (FEC), …

Lidar And Machine Learning Estimation Of Hardwood Forest Biomass In Mountainous And Bottomland Environments, Bowei Xue

Graduate Theses and Dissertations

Light detection and ranging (lidar) has been applied in various forest applications, such as to retrieve forest structural information, to build statistical models for identification of tree species, and to monitor forest growth. However, despite significant progress in these areas, the choice of regression approach and parameter tuning remains an ongoing critical question. This study focused on choosing the right spatial generalization level to transform lidar point clouds to 2D images which can be further processed by mature image processing and pattern recognition approaches. It also compared the prediction ability of popular machine learning algorithms applied to aboveground forest biomass …

The Spectacle Of Orphanhood: Reimagining Orphans In Postbellum Fiction, Afrin Zeenat

Graduate Theses and Dissertations

Orphan iconography has always been deployed in American literature and culture, but nineteenth-century American literature, fiction in particular, abounds in orphans, both real and imaginary. The orphan’s amphibious nature is hailed and demonized as the epitome of individualism and unbridled freedom, and also as the location of society’s anxiety. This complicated and conflicted construction of orphans animates the Social and cultural realm in postbellum America, foregrounding issues of class, race, and gender.

Food Waste At Retail, Erin G. Killeen Davis

Graduate Theses and Dissertations

Food waste at retail represents forgone sales and embodies store management and disposal costs. Fresh produce is the largest contributing sector to food waste at retail and bulky, seasonal products are an added challenge when stores experience a high waste event. In order to improve, retailers need to better understand the costs of food waste, as well as how management strategies can impact these costs.

Using pumpkins as an example of bulky, seasonal products, a twofold research project was conducted to better understand contributors to, and costs of food waste at the retail level. In part one, using data from …

The Ability Of Select Probiotics To Reduce Enteric Campylobacter Colonization In Broiler Chickens, Sandip Shrestha

Graduate Theses and Dissertations

Campylobacter is the leading cause of foodborne illness worldwide and is often associated with consumption and/or mishandling of contaminated poultry products. Probiotic use in poultry has been an effective strategy in reducing other enteric foodborne pathogens but not consistently for Campylobacter. As Campylobacter resides and utilizes intestinal mucin for growth, isolates selected on the basis of mucin utilization might be a strategy to screen for efficacious probiotic bacterium. In this study, bacterial isolates demonstrating increased growth rates in mucin, in vitro (trials 1 or 2), or isolates demonstrating a reduction of Campylobacter counts when co-incubated with mucin, in vitro (trials …

Population Structure Of Central Stoneroller (Campostoma Anomalum) On The Ozark Plateau In Arkansas And Missouri, Mallory Jane Jeffers

Graduate Theses and Dissertations

Stream fishes on the Ozark Plateau have been influenced both by historic events (i.e. vicariance versus dispersal) and ecological forces (i.e. flow regime). To examine the role of these processes, genetic structure of Central Stoneroller (Campostoma anomalum), an ecologically important omnivorous minnow with a broad distribution and elevated abundance, was evaluated across populations in the White River drainage of the Ozark Plateau in Arkansas and Missouri. Fin clips of five to eight individuals were taken at each of 20 sites (N=138 individuals; average=6.9), selected so as to represent two different flow regimes: intermittently flashy (N=10 sites; N=73 individuals; average=7.3/ site) …

Long-Term Effects Of Alternative Residue Management Practices On Near-Surface Soil Properties And Soybean Production In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Christopher Ryan Norman

Graduate Theses and Dissertations

Adoption of management practices that maintain or increase soil organic matter (SOM), which contains 58% carbon (C) on average, may help to mitigate climate change by sequestering atmospheric C. Therefore, the main objective of this study was to determine the long-term trends in SOM, soil C and nitrogen (N), bulk density, various soil chemical properties (i.e., pH, electrical conductivity [EC], and Mehlich-3-extractable nutrients) in the top 10 cm, and soybean yield as affected by residue burning (burning and non-burning), tillage (conventional and no-tillage), irrigation (irrigated and non-irrigated), and N-fertilization/residue level (high and low) in a wheat (Triticum aestivum L.)-soybean [Glycine …

Shiga Toxin-Producing Escherichia Coli (Stec) Detection Strategies With Formalin-Fixed Stec Cells, Christopher Adam Baker

Graduate Theses and Dissertations

Certain pathogenic Escherichia coli known as Shiga toxin (Stx)-producing Escherichia coli (STEC) are commensals in cattle, and typically cause bloody diarrhea in humans once the Stx toxin is secreted in invaded intestinal epithelial cells. Infections with STEC cells can lead to hemolytic uremic syndrome, which is commonly associated with kidney failure. Several STEC serogroups have been declared adulterants in raw, non-intact ground meat, and future regulations could potentially lead to a higher number of STEC serogroup detection strategies for these pathogenic microorganisms. Microbiological research laboratories may benefit from formalin-fixed STEC cells for periodic (daily, weekly, monthly, among others) instrument validation/calibration …

Metal Mobilization In Groundwater, Bauxite, Ar, Steven Alexander Hamlin

Graduate Theses and Dissertations

The Wilcox Aquifer of Bauxite, AR contains bauxite ore deposits that may contribute heavy metals to groundwater. Twenty-four wells were sampled for aluminum, iron, manganese, zinc, lead, barium, nitrate, sulfate, sodium, alkalinity, calcium, magnesium, chloride, pH, total organic carbon, and total dissolved solids. A Wilcoxon Rank-Sum compared the similarity of the three geographic areas covered in the study. All parameters for wells in Bauxite and Sardis failed to reject the null hypothesis, signifying that wells all occupy the Saline Formation. 2/3rds of the parameters from BFI261 and the Bauxite region did not agree, suggesting the two areas do not occupy …

Stable Isotopes As A Tool To Characterize Carbon Cycling And Develop Hydrologic Budgets In Mantled Karst Settings, Katherine Knierim

Graduate Theses and Dissertations

Isotopes of water (δ2H/δ18O), carbon dioxide (δ13C-CO2), and dissolved inorganic carbon (δ13C-DIC) were used to explore water quality, trace carbon cycling, and quantify recharge sources through mantled karst and into Blowing Spring Cave (BSC). Of the possible sources of contamination in the BSC recharge area, septic-tank effluent was hypothesized to degrade water quality at the spring outlet of BSC because of the dominance of septic tanks for waste treatment, unsuitable topography and soil for septic-tank absorption fields, increased nitrate and chloride concentrations concomitant with increased urbanization, and increased Escherichia coli with discharge. Carbon cycling between the soil and BSC was …

What's Left Over, Bryanna Jaramillo

Graduate Theses and Dissertations

The MFA thesis exhibition titled, What's Left Over, is comprised of a series of drawings as well as a large painted sculptural installation assembled as a child's fantasy world. The work explores the roots of creativity through the lens of childhood play by assembling an invented world named Lola. By exploring the relationship between the real and the imaginary, the work manifests childhood memories into a form that can be studied and better understood. Lola is an elaborate but clearly handmade world that explores an unresolved past.

The Ballistics Of Archaic North American Atlatls And Darts, Devin Brent Pettigrew

Graduate Theses and Dissertations

Preserved atlatls and darts, commonly of small size, have been found across North America from the Early to Late Archaic. Close replications of these systems were employed in a naturalistic experiment on a fresh hog carcass. The use of high-speed cameras, a radar gun, and a video analysis program to measure dart velocity and view impacts in slow motion allowed a detailed analysis of the results. The experiment captured several details about atlatl and dart ballistics, including killing potential, the effects of point beveling on dart flight and impact, traceable impact damage on bones and stone points, and the effectiveness …

Stand Strong, Stand Proud: Alternative And Pariah Femininities In San Diego's Punk Rock Community, Steve Moog

Graduate Theses and Dissertations

Since its inception nearly 40 years ago, punk rock has often been understood as a Social space for rebellion and resistance to dominant cultural norms. As such, punk rock culture becomes fertile ground for explorations of subversive constructions of genders. Drawing from ethnographic fieldwork conducted in the San Diego punk rock community, this thesis unpacks the construction, embodiment and enactment of alternative and pariah forms of femininities and examines their impact on gender dynamics within the scene. Ultimately, this thesis argues that (1) the San Diego punk rock community is a space where alternative and pariah femininities can be embodied …

Addressing Genetic Pollution From Pollen Drift On A Heterogeneous Landscape, Mattia Ciro Mancini

Graduate Theses and Dissertations

Genetically modified (GM) crops are crops in which single or multiple genes have been introduced artificially in order to obtain certain characteristics that are difficult to obtain through conventional breeding. Even though farmers have the right to freely choose what types of crops to grow, pollen mediated gene flow from GM crops to non-GM crops can limit the possibility for crops to coexist on a same landscape, resulting in economic losses that depend on the institutional arrangements and the type of property rights in place. Although it is well known that spatial variability affects the degree of cross-contamination between GM …

Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan

Graduate Theses and Dissertations

The primordial Earth which hosted the first forms of life was an environment free of oxygen. Early organisms utilized metabolisms dependent upon anaerobic conditions and incorporated systems to which oxygen is deleterious. As the content of oxygen in Earth's atmosphere increased, anaerobic organisms had to acquire methods to sense and combat oxygen and reactive oxygen species. Several mechanisms were advantageous to such anaerobic organisms which correlated transcriptional processes with the redox state of the cell so that energy may be conserved and oxygen stress recovery genes activated during periods of oxidative stress. Iron sulfur (Fe-S) cluster cofactors incorporated within RNA …

Homelessness In Arkansas, Nichelle Sullivan

Graduate Theses and Dissertations

This research aims to reveal a realistic narrative about homelessness in Arkansas through the qualitative perspective provided by people directly affected by homelessness. We interviewed experts with both theoretical and applied experience in examining the causes and different pathways into homelessness, as well as some of the avenues that can assist someone to successfully navigate out of homelessness. This research documentary focuses particularly on the experiences of homeless families headed by single women and the challenges they face in resolving homelessness. Qualitative interviews were performed and a website was created that is targeted towards helping others to find the necessary …

The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind

Graduate Theses and Dissertations

In this dissertation I examined the relationship between individual energetic status, hormone production, and life history trait expression in field-active Timber Rattlesnakes, Crotalus horridus. In chapter one I reviewed what is known regarding these relationships in snakes and defined major research goals. In chapter two I described the seasonal profile of testosterone (T) and corticosterone (CORT) in relation to the breeding season and to individual energetic status in males. Results showed that the seasonal pattern of T production in C. horridus was different than other pit viper species with similar mating patterns. Testosterone was elevated in the months leading up …

Distinguishing Macrophage Activation States By Mass Spectrometry, Matthias Manfred Knust

Graduate Theses and Dissertations

Macrophages are versatile and highly adaptive cells that are involved in a wide range of physiological processes including host defense, homeostasis or regeneration, as well as pathogenesis. They react to their microenvironment, assuming various roles based on chemical and/or physical cues, and can reversibly shift between these so-called activation states. Concurrently, the technique of immunohistochemistry is used to gain spatial information on activated macrophages on tissue sections. The aim of this work was to find mass spectral biomarkers that allow the differentiation of activation states, and establish conditions that can be used in imaging mass spectrometry (IMS) experiments to investigate …

Intestinal Inflammation Model Inducing Gut Leakage By Different Methods In Broiler Chickens Using Fitc-D As A Marker, Eduardo Vicuna

Graduate Theses and Dissertations

Traditionally, antibiotic growth promoters (AGP) have been used in food animals to reduce enteric inflammation and maintain intestinal homeostasis, thus improving performance. Due to increasing restrictions regarding the use of AGP, precise and high throughput enteric inflammation models and markers to search for effective alternatives are urgently needed. Oral administration of fluorescein isothiocyanate dextran (FITC-d) and its passage into blood can be used as a marker for tight junction permeability. FITC-d is a large molecule (3-5 kDa) which does not usually leak through the intact gastrointestinal tract barrier. However, when conditions disrupt the tight junctions between epithelial cells, the FITC-d …

Genetic Mapping Of Yield And Normalized Difference Vegetative Index In Soft Red Winter Wheat (Triticum Aestivum L.), Christopher Keith Addison

Graduate Theses and Dissertations

Wheat is the most widely cultivated cereal crop, being grown on 17% of the global crop land and as such must be adapted to an array of environmental stresses. In order to become a variety, wheat breeding lines must be tested across a range of environments for both high productivity and stability. Quantitative trait loci (QTL) mapping and indices are tools that can aid plant breeders in the selection of superior lines. Soft red winter wheat accounts for 20% of the total wheat production in the United States, being grown in the southeastern U.S. predominantly along the Mississippi River. However, …

The Effects Of Electrostatic Spraying With Organic Acids In The Disintegration Of Biofilms Formed By E.Coli O157:H7 And Salmonella Typhimurium On Spinach And Cantaloupe, Ahmad Almasoud

Graduate Theses and Dissertations

Outbreaks from the consumption of fresh produce are a concern in the United States. The consumptions of fresh produce have increased recently which expose a large segment of society to such outbreaks. Spinach and cantaloupe are minimally heated or processed before consumption which makes them a possible source of foodborne illness. The objective of this research was to investigate the effect of organic acids alone and in combination to reduce attached Salmonella Typhimurium (S.T) and Escherichia coli O157:H7 (E.coli) on spinach and cantaloupe, and to disintegrate biofilm formed by these pathogens by electrostatically spraying with two organic acids. To quantify …

Distribution Of The Egyptian Goose (Alopochen Aegyptiacus) In Northwestern Arkansas And In The United States Of America, Cameron Chesbro

Graduate Theses and Dissertations

The Egyptian Goose (Alopochen aegyptiacus) is an exotic member of the Anatidae that has been residing in northwestern Arkansas since the 1980s (Smith and James 2012). Following the discovery of Egyptian Geese in the area, not much attention has been given to the consequences of population increase. The Egyptian Goose has shown many diverse population growth patterns in areas where it has been introduced and started feral populations. The purpose of this study was to assess the current population size of the Egyptian Goose in northwestern Arkansas,and confirm successful breeding. The methods used in this study included conducting road surveys …

Improving Production Efficiency Of Beef Cow-Calf Operations, Amanda Jo Davis

Graduate Theses and Dissertations

Three studies were conducted to improve and incorporate reproductive management practices into beef cow-calf production. First study evaluated serial use of Estrotect estrous detection patches as a simple, cost-effective reproductive management tool to identify cyclic animals before breeding, distinguish between females conceiving to AI versus natural service, and determine seasonal pregnancy rate after bull removal. Also determined, was effectiveness of altered timing of GnRH treatment (1 d ± CIDR removal) in a modified 14-d CIDR-Select Synch protocol. When evaluated over a 4-wk period, estrous detection patches correctly (P < 0.01) identified 79% of cyclic and 86% of non-cyclic heifers. Patches were 96 and 98% accurate in identifying heifers and cows pregnant by AI, respectively, and were 76 and 87% accurate in identifying pregnant heifers and cows at the end of the breeding season (P < 0.01). Treatment with GnRH at CIDR removal reduced labor costs and animal handling without compromising estrous response (both ~63.0%) and AI pregnancy rates (~76 and 77%; P > 0.1). Second study determined if addition of PGF2alpha treatment on d 7 …

Phylogeny And Diversity Of Entamoeba In Cockroaches, With An Emphasis On Periplaneta Americana, Mustafa Husain Fakhri

Graduate Theses and Dissertations

While the parasitic Amoebozoan Entamoeba histolytica has been well-studied for its role in human pathogenesis, the biodiversity of invertebrate-inhabiting Entamoeba has scarcely been investigated. Using molecular methods, I searched for Entamoeba in the guts of cockroaches from four of the six Blattodean families. Entamoeba small-subunit rRNA genes were recovered from all eight species of cockroaches tested, five of which represent newly discovered hosts. Phylogenetic analysis of over 190 sequences revealed a novel and highly diverse clade of cockroach-inhabiting Entamoeba, separate from the clade predominated by vertebrate-inhabitants. These results double the known genetic diversity of Entamoeba and suggest that they may …

Prediction Of Superovulatory Response In Beef Cows Based On Serum Anti-Mullerian Hormone And Antral Follicle Number, Keith Center

Graduate Theses and Dissertations

A study investigated the use of Anti-Mullerian hormone (AMH) and/or follicle counts as a predictor of subsequent superovulatory response and embryo production in 79 beef cows. Before initiation of superovulation, ultrasonography was used to scan the ovaries of each donor cow to record the number of 3 to 5 mm follicles present, and a blood sample was collected for measure of serum AMH. At the time of embryo collection, the ovaries of donor cows were palpated to estimate the number of corpora lutea (CL) present on each ovary. Recovered embryos were evaluated for stage of development and morphological quality. Across …

Direct Fermentation Of Sweet Potato Starch Into Lactic Acid By Lactobacillus Amylovorus: The Prospect Of An Adaptation Process, Winifred Akoetey

Graduate Theses and Dissertations

Several studies have verified that lactic acid bacteria are capable of directly producing lactic acid from starch. One of these bacteria, L. amylovorus, has been studied using corn, potato, and cassava starches. However, the use of sweet potato starch, a widely available starch, has not been considered. Furthermore, there exists the possibility that the efficiency of lactic acid production can benefit from the systematic exposure of bacteria to increasing concentrations of a particular starch. In this work, fermentation studies were conducted to understand the adaptation of L. amylovorus to rising concentrations of sweet potato starch. L. amylovorus was cultured in …