Digital Commons Network^™

Polyethylene Oxide Nanofiber Production By Electrospinning, H. E. Schneider, J. G. Steuber, W. Du, M. Mortazavi, D. W. Bullock

Journal of the Arkansas Academy of Science

Electrospinning is an inexpensive technique that is used to produce nanofibers for a variety of applications. In electrospinning, a polymer solution is dispensed from a hypodermic-like syringe where an intense electric field attracts the solution to a collector while drawing the polymer into a very thin fiber. The diameter of the fiber can be controlled by tuning the process parameters such as the applied electric field, solution flow rate, distance between syringe tip and collector, and the collector geometry. In this paper we describe results from electrospinning poly(ethylene oxide) (PEO), a likely candidate for applications involving scaffolding for tissue engineering. …

Annual Report, 2015, University Of Arkansas, Fayetteville. Graduate School And International Education

Graduate School and International Education Annual Report

No abstract provided.

Arkansas Water Resources Center Annual Technical Report, 2015, Arkansas Water Resources Center

Arkansas Water Resources Center Annual Report

No abstract provided.

Mole Street Journal, December 2015, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Using Precision Agriculture Field Data To Evaluate Combine Harvesting Efficiency, Justin Carroll

Agricultural Education, Communications and Technology Undergraduate Honors Theses

Soybean crops must be harvested during a limited time period using expensive combines and associated equipment. Maximizing combine field efficiency, the ratio of the actual harvesting capacity to theoretical harvesting capacity, is an important objective of machinery managers. Spatial and temporal yield data from a 2012 CaseIH 8120 Axial-Flow combine equipped with a 30-foot MacDon D-65 Draper header and the Case-IH Advanced Farming System (AFS) yield monitoring system were used to examine field efficiency when harvesting soybean in three Arkansas Delta irrigated soybean fields during the 2015 season. Time efficiencies (TE) in the three fields ranged from 72.9 to 85.8% …

Design, Fabrication, And Testing Of A 3d Printer Based Microfluidic System, Carlton A. Mcmullen

Graduate Theses and Dissertations

A pneumatically actuated PDMS based microfluidic devices were designed and fabricated by soft-lithography. Two types of molds were fabricated out of different material for this experiment. The first mold, (device 1), was fabricated from a sheet of Polymethyl methacrylate (PMMA) material, similar to Plexiglas. The device features were micro-engraved onto the face of the material. The second mold, (device 2), was fabricated from the use of fused deposition modeling (FDM) 3D printing. The pumping efficiency of the PDMS devices was analyzed through the characterization of the micro-pumps flowrate with respect to the pumps driving pressure and the actuation frequency. Tested …

A Comparative Study Of Medicago Truncatula Transcriptomes As They Relate To Saponin Defenses Against Insect Pests, Audra Mae Rogers

Graduate Theses and Dissertations

Triterpene saponins are a class of defensive plant-derived compounds, which have a

variety of functions including antimicrobial, insecticidal, and nematicidal activities. This

research assessed the performance of the beet armyworm, Spodoptera exigua, following ad

libero feeding on Medicago truncatula accessions differing in specialized metabolite and

saponin profiles. Insect performance did not directly relate to the foliar saponin levels in the

accessions, which was measured using HPLC mass spectrometry. Accession ESP105 had the lowest foliar saponins overall, yet had similar levels of soyasaponins compared to the other accessions. Conversely, accessions A17, PRT178, and GRC43 had high foliar saponins with particularly high …

Development Of A Design Tool For Biologically Inspired Fault Adaptive Design By Strategy Mapping, Nicholas Steven Huisman

Graduate Theses and Dissertations

A design tool for Biologically Inspired Fault Adaption that utilizes the concept of strategy mapping was developed and the development process and testing is presented in this paper. The concept of strategy mapping is derived primarily from the field of military theory and supposes that for any given specific problem, that there exists a specific solution for, a single strategy can be identified for that solution/problem combination. This strategy, when applied to the specific problem yields the specific solution. This specific solution is referred to as the “tactics” of the strategy. The strategy can also be directly applied to a …

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 Effects Of Gender Differences In Networking On Pay Equity And Leadership Opportunities, Mackenzie L. Kiser

Finance Undergraduate Honors Theses

This report was undertaken in an effort to establish the causes of gender differences in pay and leadership achievement in the United States. The report attempted to add a fresh perspective to the issues of the Wage Gap and Glass Ceiling by analyzing differences between the networking habits of male and female professionals and whether they are responsible for gender inequalities. Through an online survey of 55 professionals, it was established that high income individuals were invited to more organized networking opportunities than low income individuals (p=0.103) and attended significantly more organized networking events than low income individuals(p=0.094) and men …

Method Assessment For Microalgae Quantification In Wastewater Treatment And Biofuel Production, Kristen S. Harrison

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

There is growing interest in the use of microalgae for wastewater treatment and biofuel production. However, there is not yet a reliable, user-friendly method of quantifying the biomass and lipid production of a large sample of algae. This study aims to establish and validate new methods for green microalgae quantification using the Microplate reader and the Coulter Counter. Chlorella vulgaris was chosen as the ‘ideal’ algal species for wastewater treatment and biofuel production due to its structure, lipid production, and pollution removal ability. Three traditional quantification methods -- microscope cell count, lipid separation, and chlorophyll extraction -- were compared to …

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 …

Utilization Of Weed Ecology, Tank Mixtures, And Application Technology To Improve Efficacy Of Herbicide Applications In Soybean, Christopher John Meyer

Graduate Theses and Dissertations

New herbicide-resistant soybean traits will increase the number of herbicides that can be applied in soybean and change the technology currently used to make herbicide applications in soybean. Palmer amaranth (Amaranthus palmeri) remains one of the most difficult weeds to manage in soybean and thus is the primary focus of this research. Therefore, experiments were conducted to investigate Palmer amaranth temporal emergence, control of common Arkansas weeds with new soybean herbicide programs, and the effect of application technology on dicamba-containing tank mixtures. Palmer amaranth emergence exceeded 400 plants m-2 for tillage treatments in 2013 and 2014, and tillage events typically …

Defining The Potassium Nutritional Requirements And Distribution Among Plant Parts Of Representative Soybean Cultivars From Different Maturity Groups, Md. Rasel Parvej

Graduate Theses and Dissertations

The potassium (K) requirement of soybean [Glycine max (L.) Merr.] was investigated to determine whether cultivar sensitivity to K deficiency was affected by growth habit (determinate or indeterminate) and how cultivars from each growth habit accumulate and distribute K among plant structures. We also diagnosed K deficiency across reproductive growth stages (R2-6) using trifoliolate leaf- and petiole-K concentrations and at harvest (R8) using seed-K concentration. Soybean responded similarly to K deficiency in terms of yield, selected yield components, and seed-K concentration, regardless of growth habit. The yield loss from K deficiency was greatest on the middle to upper nodes of …

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 …

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 …

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.

Community-Based Rehabilitation Supports For Social Inclusion And Work Participation Of Young Adults With Visual Impairment In Kenya: A Case Study, Philomena Jepkemboi Tanui

Graduate Theses and Dissertations

Young adults with a visual impairment (VI) experience less interaction with the community that impacts the way they relate to the world as they transition to the larger society where they face significant barriers of adjustment, exclusion, and work participation. Young adults with VI contend with cultural stigma, inequality, poor self-esteem caused by marginalization, a low quality of life (QOL), and lack of Social support systems that exist beyond the home. The aim of this study was to understand the perceptions of young adults with VI in Elgeyo-Marakwet and Kisumu Counties of Kenya concerning the barriers to community inclusion and …

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 …

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 …

The Effect Of Leucine Supplementation On Mitochondrial Biogenesis And Mitochondrial Protein Synthesis In Rats Fed A High-Fat Diet, David M. Skinner

Health, Human Performance and Recreation Undergraduate Honors Theses

This study aims to illuminate interaction between leucine supplementation and mitochondrial proteins concerned with synthesis and biogenesis. We hypothesized that supplementation with leucine will attenuate the weight gain of the high fat diet in comparison with the normal chow group, by enhancing mitochondrial biogenesis and content. We conducted a laboratory experiment using Western Blotting techniques to determine protein expression. Proteins of interest in this study include PGC-1α, COX-IV, TUFM, TFAM, and mtIF2. The findings from the research show a main effect of an increase in the expression of PGC-1 α in high fat diets. There was no difference in the …

Synthesis Of Medicinally Relevant Thiazolyl Aryl Ketones Under Mild Conditions, Danielle M. Gardner

Health, Human Performance and Recreation Undergraduate Honors Theses

Purpose: The growing amount of clinical resistance observed in current antifungal drugs and in anti-HIV pharmaceuticals is a concern in the medical community. The purpose of this study is to develop a mild synthetic process for biomedically relevant thiazolyl aryl ketones that can be used to develop antifungal and anti-HIV drugs. We hypothesized that the proposed synthetic technique would be more efficient, produce fewer unwanted byproducts, and be more tolerant of functional groups than existing methods.

Methods: Prior to each of the ketone reactions, the necessary salt was synthesized by mixing thiazole and 9-bromofluorene neat in a reaction tube heated …

Problem Solving Skill And Obesity In Children, Caitlin R. Spano

The Eleanor Mann School of Nursing Undergraduate Honors Theses

Abstract:

Introduction: Childhood obesity is a problem that leads to many serious health effects including early maturation, decreased quality of life and increased risk for cardiovascular disease. In 2012, over one third of children were considered obese (Childhood Obesity Facts 2015). Efforts have been made to reduce this number but they have not been fully successful (Nutrition Standards for School Meals 2015, Prevalence of Childhood obesity in the United States 2011-2012 2015). What other factors are causing kids to choose foods that lead to weight gain.

Literature Review: In research regarding psychological motivations of overeating, there has been a correlation …

Understanding The Causal Agent Of Rose Rosette Disease, Patrick Louis Di Bello

Graduate Theses and Dissertations

A number viruses are known to infect roses, ranging from those in the genera Nepovirus, and Ilarvirus, which have been reported since the inception of rose virology, to recently discovered viruses in the genera Carmovirus, Closterovirus, Emaravirus, Luteovirus, Rosadnavirus, and Potyvirus. Of the viral diseases in rose, arguably the most damaging is Rose rosette (RRD), which is associated with the Emaravirus, Rose rosette virus (RRV). The objective of this thesis is to fill in the gaps in knowledge on the epidemiological aspects of RRD and RRV. There has been significant progress in the epidemiology of the RRD agent prior to …

Sickeningly Sweet: Analysis And Solutions For The Adverse Dietary Consequences Of European Agricultural Law, Emile K. Aguirre

Journal of Food Law & Policy

Sixty-nine percent of adults in the United States, sixty-four percent in the United Kingdom, and over one-third worldwide are overweight or obese. These staggering figures continue to grow, with accompanying emotional, physical, and economic consequences, both for individuals and society as a whole. The role law plays in facilitating this global trend is significant, and yet puzzlingly, little recognized or understood The current food system is profoundly structurally flawed: it establishes unhealthy dietary behaviors as the default option for consumers. This Article is the first to examine how agricultural law has facilitated these unhealthier diets for the past fifty years, …

Mediating The Gm Foods Debate: Lessons From The Enduring Conflict Framework, Lisa F. Clark, Michaela J. Keet, Camille D. Ryan

Journal of Food Law & Policy

Critics of the commercialization of Genetically Modified (GM) foods in Canada and the United States oppose the economic and political forces that create and approve the technology: the industry that develops it and the governments that approve its use. The conventional narrative pits the concerned public, labeled "anti-GM," against the "pro-GM" interests of industry supported by business-friendly governments. Based on this binary view of the interests and motivations of stakeholders, conflict between government and industry appears minimal and regulatory frameworks for genetically engineered crops look as though they are primarily designed to facilitate those technologies. This paper refocuses the current …