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The Effects Of Meloidogyne Incognita And Heterodera Glycines On The Yield And Quality Of Edamame In Arkansas, Juliet Fultz

Graduate Theses and Dissertations

Edamame (Glycine max), also known as vegetable soybean, was introduced to the United States from Japan in 1890 and has been growing in popularity as a nutrient-rich, low-sugar snack in recent years. In 2012, the American Vegetable Soybean and Edamame, Inc. established the first domestic commercial processing plant in Mulberry, Arkansas and contracted local growers for production. Since the crop is harvested when seed are immature, management practices are different from those for traditional soybean. Plant-parasitic nematodes, particularly Meloidogyne incognita (southern root-knot) and Heterodera glycines (soybean cyst), are common in Arkansas and are pests of concern for edamame growers. Edamame …

Applications Of Cultural Theory And Empirical Analysis Of Sustainable Energy Policy Preferences In Arkansas, John Henry Kester Iii

Graduate Theses and Dissertations

The local policy arena is ripe for research on policy elite decisionmaking because where policy diffusion is concerned, previous studies focus on state-to-state and city-to-city dynamics. Therefore, there is a significant opportunity to expand understanding about the adoption of policies and policy diffusion at the local level. Identification of individual level determinants that signify policy adoption is a cornerstone to fostering this knowledge. This study examines such preference indicators found among policy elites in select Arkansas cities. For this research, the primary theoretical perspective for evaluating individual determinants is cultural theory, which has shown strong correlation to individual policy preference …

Rice Blast Disease In The U.S. And Africa: Determination Of Pathogen Diversity And The Identification Of Resistance Genes For Disease Management, Felix Rotich

Graduate Theses and Dissertations

Rice blast caused by Magnaporthe oryzae (= Pyricularia oryzae) B. Couch, is a leading disease of rice. Magnaporthe oryzae exhibits a high degree of diversity. The diversity of isolates of M. oryzae from Africa and the U.S. were examined using vegetative compatibility and virulence phenotyping as well as determination of variation in the avirulence gene AVRPiz-t in isolates from Africa. Also, evaluation of blast resistance genes in the interspecific rice germplasm “New Rice for Africa” NERICA was done using F2 progeny of the cross of U.S. susceptible cultivar M204 and NERICA 12. The U.S. isolates were in three vegetative compatibility …

Investigation Of The Inherent Chemical, Structural, And Mechanical Attributes Of Bio-Engineered Composites Found In Nature: Alligator Gar’S Exoskeleton Fish Scales, Wayne Derald Hodo

Graduate Theses and Dissertations

The U.S. Army has determined a huge cost savings of up to 51% can be accomplished by reducing the gross vehicle weight, for their personnel carrier, by 33%. To cut cost, composite materials are needed. Man-made composites can have superior material properties (high-strength, high-fracture toughness, and lightweight), but they are prone to delamination at the glued-layered interface. In contrast, fish scale is a natural composite that has the same material properties and, additionally, tend not to delaminate.

The focus of this study was to learn how nature integrates hard and soft materials at each length scale to form a layered …

The Role Of G-Protein Signaling In Pathogenesis In Cercospora Zeae-Maydis, Brant Smith

Graduate Theses and Dissertations

Gray leaf spot, caused by Cercospora zeae-maydis, is one of the most destructive foliar diseases of maize worldwide. C. zeae-maydis orients hyphal growth towards stomata (stomatal tropism) and forms infectious structures (appressoria) that are necessary for successful infection. Although some genes involved in pathogenesis in C. zeae-maydis have been identified, the molecular mechanisms are not well understood. In fungi, heterotrimeric G-proteins consist of three subunits (α, β, and γ) and mediate responses to environmental stimuli. They regulate diverse functions, including nutrient detection, virulence, fungal development, conidiation, secondary metabolism, and pathogenesis in many plant pathogenic fungi. This research explored the role …

The Role Of Sharing And Information Type In Children's Categorization Of Privileged And Conventional Information, Helana Girgis

Graduate Theses and Dissertations

Categorization is an essential part of our daily lives and an integral part of humans’ ability to function and interact within society. There are large bodies of research that document children’s categorization in domains such as natural kinds, artifacts and human kinds. One domain that has not been investigated is children’s ability to categorize different types of information; specifically conventional information, shareable to others with no restrictions, and privileged information, shareable to only a few. Study 1 investigated 4- and 5-year-olds and adults’ ability to categorize conventional and privileged information. All participants correctly categorized both types of information equally well …

Evaluating The Intrinsic Similarity Between Neural Networks, Stephen Charles Ashmore

Graduate Theses and Dissertations

We present Forward Bipartite Alignment (FBA), a method that aligns the topological structures of two neural networks. Neural networks are considered to be a black box, because neural networks contain complex model surface determined by their weights that combine attributes non-linearly. Two networks that make similar predictions on training data may still generalize differently. FBA enables a diversity of applications, including visualization and canonicalization of neural networks, ensembles, and cross-over between unrelated neural networks in evolutionary optimization. We describe the FBA algorithm, and describe implementations for three applications: genetic algorithms, visualization, and ensembles. We demonstrate FBA's usefulness by comparing a …

Southeastern Monochamus And Their Interactions With Healthy Shortleaf Pine Trees And Associated Ips Grandicollis Bark Beetles, Matthew Walker Ethington

Graduate Theses and Dissertations

Insects in the genus Monochamus are medium to large-sized, wood-boring beetles whose primary hosts in the Northern Hemisphere are pine trees. These beetles interact with both conifer hosts and associated insects throughout their life history. Past research has demonstrated that Monochamus are saprophagic, but recent findings show that they may colonize healthy pine trees. To determine if southeastern Monochamus could colonize healthy pines, adult Monochamus were attracted to healthy shortleaf pine trees from May to September, 2014, using host volatiles, Ips bark beetle kairomones, and congeneric pheromones. Subsequent development of oviposited eggs from 18 host trees was monitored. The results …

Sampling Terrestrial Arthropod Biodiversity: A Case Study In Arkansas, Michael Joseph Skvarla

Graduate Theses and Dissertations

The Interior Highlands is a biodiversity hotspot, with at least 200 known endemic species, but is understudied compared to hotspots, such as the Southern Appalachians. In order to begin to rectify this issue, a nine month study was conducted from mid-March through early December at a 4 ha site at Steel Creek, Buffalo National River, in Newton County, Arkansas. Thirteen collecting methods were employed, including three colors of Lindgren funnel trap, five colors of pan trap, Malaise traps, canopy traps with upper and lower collectors, pitfall traps, and Berlese-Tullgren extraction of leaf litter, which resulted in the collection of 1311 …

A Regional Approach To Analysis Of Food Security Framework And Policies Of The Economic Community Of West African States (Ecowas), Hannah Elizabeth Shear

Graduate Theses and Dissertations

Food security is always a concern for consumers, but especially for those in West Africa, where the population of food insecure people has continued to grow over the past decade despite attempts by initiatives such as the World Food Program and the establishment of Millennium Development Goals. The people of West Africa are subject to repetitive natural disasters and are often in political upheaval. Many economic policies have been established to mitigate the impact that production disasters have on the consumers; one of these policies is the utilization of regional food reserves.

In 2010, the Economic Community of West African …

Impacts Of Feedstock And Parboiling Conditions On Quality Characteristics Of Parboiled Rice, Kanokporn Leethanapanich

Graduate Theses and Dissertations

Parboiling involves soaking, steaming, and drying, and is known to improve head rice yield (HRY), remove chalkiness, and retain nutrients. Because of an increasing number of rice cultivars developed, commingling of rice may happen during harvesting, distributing, or storage. Using commingled rice with a wide range of gelatinization temperatures (To) as a feedstock may cause inconsistent parboiled rice products. Therefore, this study was aimed at investigating the effect of soaking temperature and steaming duration on the quality of parboiled, commingled rice. Rough rice samples of individual or commingled rice cultivars with different To ranges were soaked at different temperatures (25, …

The Abundance And Distribution Of Mallards In The Lower Mississippi Alluvial Valley Of Arkansas, John Andrew Herbert

Graduate Theses and Dissertations

The management of wintering waterfowl in North America requires flexibility because of constantly changing landscapes and conditions. Many mallards use the lower Mississippi Alluvial Valley (MAV) for wintering habitat, making this an area of emphasis for improving management strategies. In this study, I used mallard observation data from 2009-2014 aerial surveys collected in the Arkansas portion of the lower MAV to explain the abundance and distribution and of mallards. Using spatial hierarchical models and breaking covariate data to 2x2 km grid cells, I analyzed how covariates relate to the changes of abundance and distributions within and among surveys. Mallard abundance …

Evaluation Of Conservation Practices Through Simulation Modeling And Tool Development, Gurdeep Singh

Graduate Theses and Dissertations

For the first objective, predicted impacts of selected Mississippi River Basin Initiative (MRBI) conservation practices (CPs) on sediment and nutrient loss were assessed. The study area was L’Anguille River Watershed (LRW), a priority focus watershed of the MRBI program and the simulated CPs were filter strip, critical area planting, grade stabilization structure, irrigation land leveling, irrigation pipeline, irrigation water management, and nutrient management. The Soil and Water Assessment Tool (SWAT) model was calibrated (1998 – 2005) and validated (2006 – 2012) for flow, sediment, total phosphorus (TP), and nitrate-nitrogen (NO3-N) at the Colt site (503 sq. km. drainage area) and …

Cotton Injury Due To Soil- Or Foliar-Applied Herbicides: An Assessment Based On The Influences Of Genetic, Agronomic, And Environmental Factors, Brandon William Schrage

Graduate Theses and Dissertations

Increasing populations of glyphosate-resistant weeds, such as Palmer amaranth, have prompted growers to pursue alternative means of weed control in cotton. In many cropping systems, this means the utilization of older chemistries and residual herbicides. The goal of this research was to evaluate and understand the agronomic and environmental factors that affect the inconsistent injury often associated with these herbicides as well as determine the impact of Palmer amaranth emergence date on seed production, biomass, and cotton yield. Experiments were conducted in three counties in Arkansas giving a distinct range of climate and soil texture. Injury, biomass, and number of …

Extraction, Purification And Characterization Of A Pure Peptide From Soybean To Demonstrate Anti-Proliferation Activity On Human Cancer Cells And Test The Ability Of Soy Peptide Fractions In Reducing The Activity Of Angiotensin-I Converting Enzyme, Srinivas Jairam Rayaprolu

Graduate Theses and Dissertations

Proteins are of major interest for nutritional value, functionality and sensory characteristics in foods, and biological activity as health-promoting ingredients. A large number of potential biological activities are encrypted within the primary structures of animal and plant proteins. This research has been based on utilizing a legume by-product, soybean meal, to obtain value-added protein products. Forty four Arkansas grown soybean lines were subjected to analysis for protein and amino acid (profile) content to select lines that have high protein attributes. Three soybean lines, R95-1705 (high yielding, non-transgenic and high protein), N98-445A and S03-543CR (bred for high oleic acid - monounsaturated …

Stink Bugs: Spatial Distribution, Pecan Phenological Susceptibility And Sampling Program, Brian Cowell

Graduate Theses and Dissertations

An effective management program for stink bugs (SBs) in pecan groves requires knowledge of: stages of the pecans susceptible to SB damage; strata of the tree with SB damaged nuts; a practical SB monitoring method; and, effects of landscapes contributing SBs into pecan groves.

Stink bugs produced feeding punctures in pecan shucks at all phenological stages. Pecans punctured before the dough stage drop from the tree. Kernel damage occurs in the pecans’ dough stage, whereas mature pecans are not damaged.

The pecans collected from the whole tree using the tree shaker had significantly less punctures than the pecans collected from …

Prediction Of Rupture In Abdominal Aortic Aneurysm, Qusay Alfaori

Graduate Theses and Dissertations

Studying the development of abdominal aortic aneurysm (AAA) through quantification of its growth kinetics and rupture criteria is important to decrease the risk of this life-threatening event. Uniaxial and biaxial testing of healthy and time-dependent Type-I collagen degraded aortic specimens from pigs was performed. Stress-strain suitable mathematical models describing the behavior of abdominal aortic tissue were utilized to derive specific tissue properties and parameters. Reduction in Type-I collagen fraction was observed using picrosirius red staining method, bright field microscopy, and MATLAB. Finite Element Modeling (FEM) of healthy and time-dependent Type-I collagen degraded abdominal aortas were performed using ABAQUS finite element …

Swat Model Simulation Of Bioenergy Crop Impacts On Water Quality In Cache River Watershed, Eeshan Kumar

Graduate Theses and Dissertations

Energy security through increased biofuel production is one of the components of the Energy Independence and Security Act (EISA) 2007. As per EISA 2007 mandate, appropriate independent research institutes are required to assess concerns to natural biodiversity due to biofuel production and report it to the Congress through the Environment Protection Agency (EPA). Planners, researchers, and agencies concerned with environmental regulations, ideally, would like to have location-specific information about the impacts for developing appropriate management interventions. This study examines long-term impacts on water quality in response to targeted (i.e. marginal lands) production of biofuel crops by setting up two SWAT …

Individual Differences In Anxiety Sensitivity And Emotional Avoidance: Potential Links In The Association Between Internalizing Problems And Peer Victimization, Juventino Hernandez Rodriguez

Graduate Theses and Dissertations

Chronic peer victimization has been linked to short- and long-term problems such as anxiety, depression, and aggression (Hawker & Bouton, 2000; Reijntjes, Kamphuis, Prinzie, & Telch, 2010; Reijntjes, Kamphuis, Prinzie, Boelen, van der Schoot, & Telch, 2011). Most children are able to escape the role of stable victim, but some struggle to end victimization and the negative trajectory associated with it. The present study explored individual differences in anxiety sensitivity and emotional avoidance, developmental vulnerabilities that heighten children’s risk for internalizing problems, as possible predictors of children’s level of peer victimization. Participants were 677 fourth-grade students and their teachers. Multi-informant …

Blackberry Virosome: A Micro And Macro Approach, Archana Khadgi

Graduate Theses and Dissertations

Viruses pose a major concern for blackberry production around the world with more than 40 species known to infect the crop. Virus complexes have been identified recently as the major cause of plant decline with blackberry yellow vein disease (BYVD) being the most important disease of the crop in the Southern United States. The objective of this research was to study the blackberry virosome in both the macro and micro scale. The large scale approach involves identification of the major viruses known to be associated with BYVD in the Southern United States as well as the identification of other viruses …

Economic Feasibility Of Aquaponics In Arkansas, Leah Ashley English

Graduate Theses and Dissertations

Concerns regarding population growth and resource scarcity have led to a recent renaissance of food production research. Over the past few decades, scientists have discovered new and innovative methods for growing food that, cumulatively, may hold the key to efficiently and sustainably feeding an ever-increasing world population. One method, known as aquaponics, has shown promise as being a sustainable solution for producing food locally in all parts of the world. Although many studies have shown aquaponic food production to be technically feasible, there are relatively few studies concerning the economic feasibility of aquaponics in various regions. To determine whether aquaponics …

Storage Of Round And Square Switchgrass Bales: Effect Of Storage Time And Fungal Inoculation On Saccharification Efficiency, Noaa Frederick

Graduate Theses and Dissertations

To produce fermentable sugars from lignocellulosic biomass feedstock, severe pretreatment conditions are needed (either high acid concentration, temperature, or retention times). High severities can produce toxic byproducts which inhibit enzymatic hydrolysis or fermentation. In order to reduce pretreatment severities (and thus increase enzyme and fermentation efficiency), the white-rot fungus Pleurotus ostreastus was seeded into square and round bales of Kanlow switchgrass (Panicum virgastum L.) and left in the field over a period of 9 month. The laccase producing fungus is believed to selectively degrade lignin, a common plant structural polymer, which can function as an enzymatic inhibitor. Samples were taken …

Systematics Of Testudacarine Torrent Mites (Parasitengona: Torrenticolidae), Joseph Charles O'Neill

Graduate Theses and Dissertations

Thirteen new species of Testudacarus (Torrenticolidae: Testudacarinae) are described, four species are redescribed, and the status of previously problematic species are addressed. For Testudacarinae this represents the first published: 1) descriptions from multiple specimens (therefore providing ranges); 2) colored photographs; 3) explicit illustrations and discussion of sexual dimorphism within the subfamily; 4) genetic data. A comprehensive literature review is also included.

Responses Of Two Strains Of Broilers To Diets Varying In Essential Amino Acid Density And Energy Levels, Tyler James Clark

Graduate Theses and Dissertations

The responses of two different commercial strains of broilers to diets varying in overall amino acid levels and metabolizable energy levels were observed. Amino acid levels used were 80%, 90%, 100%, 110%, 120%, and 130% of Ross recommended minimum digestable levels of essential amino acids. Energy levels used were either below or above Ross recommended metabolizable energy levels. Diets were fed for 56 days. The two strains were a fast growing broiler strain and a slower growing broiler strain. A selection of birds from each pen was processed at 35, 43, and 56 days of age. Average body weights, cumulative …

Applying Molecular And Phenotypic Tools To Characterize Flesh Texture And Acidity Traits In The Arkansas Peach Breeding Program And Understanding The Crispy Texture In The Arkansas Blackberry Breeding Program, Alejandra Andrea Salgado Rojas

Graduate Theses and Dissertations

Quantitative trait loci (QTL) utilizing a pedigree-based analysis (PBA) approach was performed in the peach breeding program for the first time. The pedigree consisted of seven-F1 populations, their parents, ancestors, and cultivars. Flesh firmness and titratable acidity (TA) were examined in 2011, 2012, and 2013. For TA, a consistent and strong QTL was identified on the proximal end of linkage group (LG) 5 of the peach genome. For flesh firmness, two QTLs were located on LG 4. The first QTL was located on the chromosomal region where the slow-melting flesh (SMF) DNA test was identified, and the second QTL was …

Leptin Regulates The Expression Of Autophagy-Related Genes In Chickens, Peter Olawale Ishola

Graduate Theses and Dissertations

Autophagy or cellular self-digestion, a lysosomal degradation pathway that is conserved from yeast to human, plays a key role in recycling cellular constituents, including damaged organelles. It also plays a pivotal role in the adaptation of cells to a plethora of distinct stressors including starvation. Autophagy has been extensively studied in mammals and yeast, but little is known in avian species. Thus, the major objective of the present study was to determine the effects of leptin on autophagy-related genes in chicken hypothalamus, muscle and liver. Leptin is an adipocytokine that is mostly produced by white adipose cells in mammals (as …

Spring Migration Ecology Of American Woodcock (Scolopax Minor) In The Central Management Region Of The United States, Cari Elizabeth Sebright

Graduate Theses and Dissertations

American woodcock (Scolopax minor) is a migratory game bird in population decline since the start of monitoring in 1968. Researchers are interested in gaining knowledge of spring migration ecology to improve migration habitat and mitigate population decline. I captured six woodcock with mist and hand nets on nocturnal habitat and marked them with VHF (very high frequency) transmitters in northern Arkansas. I documented the distance they traveled between nocturnal and diurnal habitats (n=27), and documented diurnal vegetation characteristics at sites used (n=25). I found that woodcock moved an average of 370 m (SE 25.31 m) with the longest movement being …

A Descriptive Case Study Of Individuals With Presumed Ocular Histoplasmosis Syndrome Utilizing A Facebook Support Group, Lisa Aimee Thompson

Graduate Theses and Dissertations

This dissertation describes the experiences of people diagnosed with presumed ocular histoplasmosis syndrome as they participate in an online peer-support group on Facebook. This is a descriptive case study of factors related to adjustment, treatment, emotional distress, access to services, and online peer support. Participants were interviewed and observed, and documents were collected to describe this phenomenon.

Wittgenstein's Liberating Word: A Meditation On Philosophy And God, Joshua Timothy Kenyon Daniel

Graduate Theses and Dissertations

This project is an attempt to understand the nature of religious belief through the lens of Ludwig Wittgenstein’s philosophical perspective. Chapter One outlines Wittgenstein’s approach to language and meaning and explores the tension that many contemporary analytic philosophers of religion find in Wittgensteinian approaches to religious belief. Chapter Two addresses concerns Wittgenstein had with Frege’s understanding of logic and the limits of thought and ties it to criticism from Wittgensteinian philosophers about the possibility of making any sense of religious belief. Chapter Three pulls together the concerns of the previous two chapters and attempts to reconcile them. A schematic outline …

Field Screening Of Diverse Soybean Cultivars For Flood Tolerance, Jane Achando Khatenje Mokua

Graduate Theses and Dissertations

Flooding can significantly reduce soybean growth, development, and yield. Therefore, screening and identification of flood-tolerant soybeans will enhance development of cultivars that are well suited for flood-prone areas. Sets of screening tests were conducted in Stuttgart, Arkansas using three separate but related experiments, with the purpose of establishing effective flood tolerance screening protocol that can identify tolerant and sensitive cultivars. Each experiment was completely randomized with three replications. The first experiment involved screening of 256 maturity group (IV and V) cultivars. Flooding was imposed at the fifth-node (V5) or first-bloom (R1) stage for ten days. Post-flood visual ratings and stand …