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Influence Of Poultry-Litter Biochar On Early-Season Growth In Cotton, Taylor Dayne Coomer Dec 2013

Influence Of Poultry-Litter Biochar On Early-Season Growth In Cotton, Taylor Dayne Coomer

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Cotton (Gossypium hirsutum L.) is known for being sensitive to cool, wet soils, especially in the early stages of growth. Amendments such as soil fertilizers and manures added to soil can aid cotton seedlings in development and nutrient uptake. However, soil fertilizers and manures can be costly and detrimental to the environment, and alternatives such as the addition of biochar have been considered. Biochar is a high-carbon, nutrient-rich charcoal produced from organic matter that has gone through pyrolysis. Biochar has been shown to improve plant yield, soil microbial response, soil structure, soil cation-exchange capacity, and water-use efficiency, however research on …

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Reservoir Management Techniques To Enhance Biological Productivity And Protect Water Quality, Ben Alan Thompson Dec 2013

Reservoir Management Techniques To Enhance Biological Productivity And Protect Water Quality, Ben Alan Thompson

Graduate Theses and Dissertations

Three reservoirs of similar size, watershed land use, and qualitative characteristics in northwest Arkansas, USA were selected to compare the effects of chemical fertilization and pulsed artificial-upwelling on whole-lake productivity, specifically primary production and phytoplankton biomass. Numerous water quality parameters were quantified over a two year period (2011-13) with the goal of understanding how each management technique would stimulate productivity. This experiment was the first step towards a larger goal to ultimately enhance sport fish production. The first year of monitoring occurred in 2011 and served as a control year for the three lakes. Treatments were initiated in two of …

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Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith Dec 2013

Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith

Graduate Theses and Dissertations

Sustainability in agriculture is paramount to assuring continued production from our most naturally fertile soils. Storing carbon (C) in soil as organic matter through sustainable agricultural management practices can both remove atmospheric C and improve soil quality. The objective of this study was to evaluate the long-term effects of water management (irrigation and dryland), residue management [burn and no-burn, conventional (CT) and no-tillage (NT)] and residue/fertility level (high and low) on soil respiration and aggregate stability in a wheat- (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], double-crop system in a silt-loam soil (Aquic Fraglossudalf) in the Mississippi River Delta …

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Evaluating Economic Impacts Of Switchgrass Harvest Time, Nathanial Elsworth Cahill Dec 2013

Evaluating Economic Impacts Of Switchgrass Harvest Time, Nathanial Elsworth Cahill

Graduate Theses and Dissertations

This thesis deals with cost of production for cellulosic energy crops of switchgrass, miscanthus, and energy sorghum. The first chapter explains the rationale for development of decision support software called Energy Crop Analysis & Planning (ENCAP) and Switchgrass Harvest Date, Yield, Nutrient Removal Estimator (SHYNE). The second chapter examines harvest date implications on yield, nutrient removal, opportunity cost of modified sale dates, and post-harvest storage losses. This harvest date analysis leads to a profit maximizing harvest date from the perspective of the producer. While this harvest date may be optimal for the producer, biorefineries may be interested in sourcing switchgrass …

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Hydrogeology And Chemical Characterization Of Hydrocarbon In Domestic Water Wells, Rancho Villa Subdivision, Rogers, Arkansas, Janelle Renee Sherman Dec 2013

Hydrogeology And Chemical Characterization Of Hydrocarbon In Domestic Water Wells, Rancho Villa Subdivision, Rogers, Arkansas, Janelle Renee Sherman

Graduate Theses and Dissertations

This project is centered on the Rancho Villa community in Rogers, Arkansas where several residents have had hydrocarbon contamination in their domestic water wells. The goal of this project was to understand the hydrogeology in the study area, characterize the contaminant chemically, and determine the source of the contaminant. The hydrogeology of the area was determined from previous theses. Seventeen samples were taken from the wells in the Rancho Villa community; each sample was analyzed for geochemical parameters and by Gas Chromatography/Mass Spectrometry (GC/MS) for organic compounds analysis. Four of the 17 samples had a visible non-aqueous layer of hydrocarbon …

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Contributing Factors That Affect The Achievement Of African-American Females Taught By Caucasian Teachers On The Arkansas Literacy Exam: A Case Study, Felicia Renee Smith Dec 2013

Contributing Factors That Affect The Achievement Of African-American Females Taught By Caucasian Teachers On The Arkansas Literacy Exam: A Case Study, Felicia Renee Smith

Graduate Theses and Dissertations

This qualitative intrinsic case study was designed to assist Caucasian educators with the researched academic skills and behaviors to engage African-American females in the learning environment. The study provided strategies and recommendations to promote self-worth, self-motivation, self-efficacy, and morale in African-American females when they did not perform as well as or higher than their Caucasian peers in a high school English classroom on the state literacy examination instructed by a Caucasian teacher. The research site was a low socioeconomic urban high school with a majority of minorities with several native based home languages. The study took an in-depth approach to …

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Patient Risk And Data Standards In Healthcare Supply Chain, Paiman Farrokhvar Dec 2013

Patient Risk And Data Standards In Healthcare Supply Chain, Paiman Farrokhvar

Graduate Theses and Dissertations

Patient safety is one of the most important health care challenges. It is a big concern since 1 in every 10 patients around the world is affected by healthcare errors. The focus of this study is given to preventable adverse events that caused by the errors or system flaw that could have been avoided. In this study, simulation models are developed using Arena to evaluate the impact of GS1 data standards on patient risk in healthcare supply chain. The focus was given to the provider hospital supply chain operations where inventory discrepancy and performance deficiencies in recall, return, and outdate …

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Developing A Presumptive Test For Select Synthetic Cannabinoids, Carrie Snyder Dec 2013

Developing A Presumptive Test For Select Synthetic Cannabinoids, Carrie Snyder

Graduate Theses and Dissertations

Synthetic cannabinoids (SC's) began to gain popularity around the world in 2009. Since then, many of the compounds have been outlawed and methods developed to detect them and their metabolites using mass spectrometry. Our work investigated the possibility of developing a colorimetric presumptive test. The SC JWH-019 was synthesized and its ketone targeted as a possible reaction site. Many SC's contain ketones and thus a reaction at this site would be applicable to many of the compounds. Since JWH-019 is costly and time consuming to synthesize, much of the experimental work was done using benzophenone (BP). BP contains a diaryl …

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Enhanced Pancreatic Beta-Cells Proliferation And Functionality, Hanan Abdulaziz Alismail Dec 2013

Enhanced Pancreatic Beta-Cells Proliferation And Functionality, Hanan Abdulaziz Alismail

Graduate Theses and Dissertations

Biologically functional beta-cells proliferate at an extremely low rate with limited turnover capacity. This cellular property hinders cell-based therapy for clinical applications. Many attempts have been made to develop techniques that allow large quantities of production of clinically relevant islet β-cells in vitro. A line of studies demonstrates that functional beta-cells can proliferate under certain circumstances, providing hope for generating and expanding these cells in vitro and transplanting them into the recipient. In this study, we showed that a membrane substrate offers a better niche for beta cell proliferation and insulin secretion. Mouse beta cells were grown on a tissue …

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Development Of Novel Antifungal Peptides Based On A Natural Model Of Histatin-5 Peptide, Duy Tu Nguyen Dec 2013

Development Of Novel Antifungal Peptides Based On A Natural Model Of Histatin-5 Peptide, Duy Tu Nguyen

Graduate Theses and Dissertations

Our research group is working toward the development of novel antifungal peptides based on a natural model of peptide histatin-5. Histatin-5 is found in human saliva and known to protect our body against oral infections by Candida species. Candidiasis, or an infection caused by Candida species, is considered one of the most medically important fungal infections worldwide. Blood stream infections caused by Candida species are the fourth leading cause of hospital-acquired fungal infections that is associated with high mortality rates and high costs of treatment. This study investigated the modes of action of histatin-5 with the use of one 16-mer …

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Towards The Total Synthesis Of Antascomicin B. Efforts To Construct The C1-C21 Fragment, Juliette Rivero-Castro Dec 2013

Towards The Total Synthesis Of Antascomicin B. Efforts To Construct The C1-C21 Fragment, Juliette Rivero-Castro

Graduate Theses and Dissertations

Antascomicin B is a macrolide isolated from a strain of Micromonospora. It possesses structural similarities to FK506 and rapamycin and exhibits potent binding ability to FKBP12. Recent reports suggest that small molecule ligands of FKBP12 possess potent neuroprotective and neurodegenerative properties in mouse models of Parkinson's disease. Our approach to the C1-21 fragment of antascomicin B involves an asymmetric amino-Claisen rearrangement originally developed by Tsunoda et al.35 report the scalability of the preparation and rearrangement of an allylic amide possessing a silyloxy group at the terminal position of the alkene. The Tsunoda-Claisen rearrangement uses inexpensive (S)-α-methylbenzylamine as the chiral …

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The Role Of Histone H3 And H4 In Centromere Function And Genome Integrity, Payel Chaudhuri Dec 2013

The Role Of Histone H3 And H4 In Centromere Function And Genome Integrity, Payel Chaudhuri

Graduate Theses and Dissertations

Histone H2A plays an important role in chromosomal segregation among parent and daughter cells during mitosis. While it is established that this histone is important in maintaining chromosome number in cell, further work is carried out to explore the role of other histones like H3 and H4 for similar effects. A systematic study is initiated by screening a library based on mutation of different amino acid residues in these histones. This detailed screening identified specific regions within H3 and H4, which are critically important for centromeric function. These histones residing near the DNA entry/exit region of nucleosome effects the functionality …

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The Color And Consistency Of Steaks And Ground Beef Produced From Mature Bulls, Jace Joseph Hollenbeck Dec 2013

The Color And Consistency Of Steaks And Ground Beef Produced From Mature Bulls, Jace Joseph Hollenbeck

Graduate Theses and Dissertations

Two experiments were conducted to compare the color and cooked attributes of steaks and ground beef produced from mature bulls. Beef from mature bulls was used to test the effects of lactic acid (LA) enhancement solution pH (2.5, 3.0, or 3.5; B25, B30, B35, respectively) on fresh (5 d of display) and cooked color and tenderness of strip loin steaks (Exp. 1) and the effect of high pH trim on precooked ground beef patties (Exp. 2). In experiment 1, mature bull strip steaks were enhanced to 111% with a LA, sodium bicarbonate, and tap water solution, in comparison to USDA …

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Molecular And Biochemical Mechanisms Of Pathogenesis In The Maize Foliar Pathogen Cercospora Zeae-Maydis, Winfred-Peck Dorleku Dec 2013

Molecular And Biochemical Mechanisms Of Pathogenesis In The Maize Foliar Pathogen Cercospora Zeae-Maydis, Winfred-Peck Dorleku

Graduate Theses and Dissertations

GLS is a serious foliar disease of maize, a major staple crop grown commercially in the USA for both human and animal feed production, and increasingly, for ethanol production. The disease is caused by two Cercospora species, C. zeae-maydis and C. zeina, both of which infect maize in the USA and in other parts of the world, with yield losses potentially greater than 50%, depending on local conditions. In culture, C. zeae-maydis produces a phytotoxic, host non-specific perylenequinone, cercosporin, and abscisic acid (ABA), for which there is no known pathological or physiological function in the fungus. Experimental evidence indicates …

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Monodentate, Bidentate And Photocrosslinkable Thiol Ligands For Improving Aqueous Biocompatible Quantum Dots, Hiroko Takeuchi Dec 2013

Monodentate, Bidentate And Photocrosslinkable Thiol Ligands For Improving Aqueous Biocompatible Quantum Dots, Hiroko Takeuchi

Graduate Theses and Dissertations

Water-soluble Quantum Dots (QDs) are highly sensitive fluorescent probes that are often used to study biological species. One of the most common ways to render QDs water-soluble for such applications is to apply hydrophilic thiolated ligands to the QD surface. However, these ligands are labile and can be easily exchanged on the QD surface, which can severely limit their application. As one way to overcome this limitation while maintaining a small colloidal size of QDs, we developed a method to stabilize hydrophilic thiolated ligands on the surface of QDs through the formation of a crosslinked shell using a photocrosslinking approach. …

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Physical And Biochemical Factors Affecting Breast Fillet Tenderness In Broilers Reared For Divergent Market Demands, Valerie Belle Brewer Dec 2013

Physical And Biochemical Factors Affecting Breast Fillet Tenderness In Broilers Reared For Divergent Market Demands, Valerie Belle Brewer

Graduate Theses and Dissertations

Market trends have dictated that broilers be reared for divergent market demands for decades. Also, broiler genetic strains have been adapted to meet market demands which include: genetic selection for improved breast meat, the practice of growing birds to older ages and greater market weights to meet demands, and decreasing postmortem (PM) aging time to improve processing efficiency and fillet yield. These production practices can also affect product quality, specifically boneless breast fillet tenderness and water-holding capacity. To address these factors, a series of experiments were conducted to determine the effect of strain and slaughter age on meat quality parameters, …

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Congruent And Incongruent Effects Of Ethnic Music On Ethnic Menu Item Selection, Ryan David Muniz Dec 2013

Congruent And Incongruent Effects Of Ethnic Music On Ethnic Menu Item Selection, Ryan David Muniz

Graduate Theses and Dissertations

This study investigated what impact ethnic music had on ethnic menu item selection. College students were randomly divided into three groups and listened to one randomly assigned sound treatment in sensory booths. Three hundred and five participants completed the questionnaire with measures of expected price value and willingness to pay value. One of the groups listened to an Italian folk music, the second group listened to a Thai folk music, and the third group listened to a restaurant background noise in order to examine if the music will impact each participant menu items selection and perceived price values. The result …

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Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha Dec 2013

Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha

Graduate Theses and Dissertations

The search for past or present life on Mars is, for now, limited to surface environments. An often neglected surface environment that could have served as an abode for life and could presently preserve evidence of that life is that of rock coatings. Rock coatings are mineral accretions on rock surfaces. On Earth, they are widespread and occur with considerable chemical diversity. There is growing evidence for a biotic role in their formation on Earth, particularly with respect to rock varnish. As a result, rock varnish has become a target of astrobiological interest on Mars, where varnish-like coatings have been …

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In Vitro Analysis Of Short Chain Fatty Acids And Human Fecal Microbiota Stimulated By Pectin Sources, Byungjick Min Dec 2013

In Vitro Analysis Of Short Chain Fatty Acids And Human Fecal Microbiota Stimulated By Pectin Sources, Byungjick Min

Graduate Theses and Dissertations

As interest increases for colonic health, various studies have been conducted to investigate functional ingredients for host health and prevention of chronic disease in humans such as colon cancer and Type 2 diabetes. In particular dietary fiber has been reported to have beneficial effects on colonic health. More recently, dietary fiber has been categorized based on its characteristics and numerous studies have been conducted to determine correlations with chronic diseases. Pectin is a naturally occurring biopolymer that has been used in various applications for purposes of pharmaceutical and biotechnology. Pectin is a soluble dietary fiber and can be entirely fermented …

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Quantitative Trait Loci Associated With Waterlogging Tolerance In A Soft Red Winter Wheat Mapping Population, Diana Carolina Ballesteros Benavides Dec 2013

Quantitative Trait Loci Associated With Waterlogging Tolerance In A Soft Red Winter Wheat Mapping Population, Diana Carolina Ballesteros Benavides

Graduate Theses and Dissertations

Waterlogging is caused when water stays superficially in the soil for an extended period of time, creating an anaerobic environment which decreases plant growth and grain yield at maturity. Despite the impact of waterlogging on wheat production both globally and in the southeastern U.S., very little is known about the genetic control of waterlogging tolerance in wheat. The objective of this study was to determine the amount of genetic variation for vegetative stage waterlogging tolerance present within a wheat recombinant inbred line (RIL) population and to identify quantitative trait loci (QTL) associated with tolerance and productivity. Experiments were carried out …

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Effect Of Electrostatic Spraying Of Food-Grade Organic And Inorganic Acids, And Grape Seed Extract On Salmonella Typhimurium And Escherichia Coli O157:H7 On Spinach And Iceberg Lettuce, Vijayalakshmi Ganesh Dec 2013

Effect Of Electrostatic Spraying Of Food-Grade Organic And Inorganic Acids, And Grape Seed Extract On Salmonella Typhimurium And Escherichia Coli O157:H7 On Spinach And Iceberg Lettuce, Vijayalakshmi Ganesh

Graduate Theses and Dissertations

The safety of fresh produce is often challenged by the sporadic incidences of outbreaks owing to Salmonella Typhimurium (S.T.) and Escherichia coli O157:H7 (E.c.). Washing and current disinfection strategies do not completely decontaminate leafy greens such as spinach and iceberg lettuce. Therefore, more effective treatments are essential to ensure the microbial safety of the produce at the selling point. Here, a multiple hurdle approach was applied: (1) Natural antimicrobials - organic acids (malic, lactic and tartaric acids; MA, LA, TA, respectively) and plant extract (grape seed extract, GSE) and (2) Application method - Electrostatic spraying, was …

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Development And Evaluation Of Chitosan Particle Based Antigen Delivery Systems For Enhanced Antigen Specific Immune Response, Bhanuprasanth Koppolu Dec 2013

Development And Evaluation Of Chitosan Particle Based Antigen Delivery Systems For Enhanced Antigen Specific Immune Response, Bhanuprasanth Koppolu

Graduate Theses and Dissertations

Particle-based vaccine delivery systems are under exploration to enhance antigen-specific immunity against safe but poorly immunogenic polypeptide antigens. Chitosan is a promising biomaterial for antigen encapsulation and delivery due to its ability to form nano- and microparticles in mild aqueous conditions thus preserving the antigenicity of loaded polypeptides. The objective of this work is to develop a chitosan particle based antigen delivery system for enhanced vaccine response. Chitosan particle sizes, which ranged from 300 nm to 3 ìm, were influenced by chitosan concentration, chitosan molecular weight and addition rate of precipitant salt. The composition of precipitant salt played a significant …

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Relationships Between Landscape Factors And Crayfish Density And The Interacting Effects Of Grazing And Increased Sedimentation On Algal Biomass, Katheryn Haley Rose Dec 2013

Relationships Between Landscape Factors And Crayfish Density And The Interacting Effects Of Grazing And Increased Sedimentation On Algal Biomass, Katheryn Haley Rose

Graduate Theses and Dissertations

In recent years in the United States there has been a rapid expansion in anthropogenic sources of sediment in streams including construction, agriculture, and drilling for natural gas. Potential effects land disturbance associated with activities from natural gas development on aquatic biota in surrounding streams have not yet been well documented. An increase in inorganic sediment in streams can be detrimental to organisms through a variety of mechanisms including alteration of dominant substrate type, higher turbidity resulting in lower visibility, and burial of food resources such as algae and detritus. Increasing sedimentation in stream environments through anthropogenic disturbance is a …

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University Housing Newsletter, November 2013, University Of Arkansas, Fayetteville. University Housing Nov 2013

University Housing Newsletter, November 2013, University Of Arkansas, Fayetteville. University Housing

University Housing Newsletter

No abstract provided.

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Jeanne Clery Disclosure Of Campus Security Policy And Campus Crime Statistics Report, 2012, University Of Arkansas, Fayetteville. Police Department Oct 2013

Jeanne Clery Disclosure Of Campus Security Policy And Campus Crime Statistics Report, 2012, University Of Arkansas, Fayetteville. Police Department

Jeanne Clery Disclosure of Campus Security Policy

No abstract provided.

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Versatile Multichannel Capillary Biosensor System, Xiao-Li Su, Zungzhong Ye, Qian Sun, Yanbin Li Oct 2013

Versatile Multichannel Capillary Biosensor System, Xiao-Li Su, Zungzhong Ye, Qian Sun, Yanbin Li

Patents Granted

The multichannel capillary biosensor system describe includes a selecting valve system for selection of the sample or a reagent. The selecting valve system is connected to a second valve system accommodating a sensing channel and a first bypass channel. The second valve system is connected to a directing valve system having at least two positions, with a first position being connected to a second bypass channel and a second position being connected to a detector for detecting the analyte. The device has a pump connected at one end to the second bypass channel and the detector and at a second …

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Effects Of Environmental Factors And Nutrient Availability On The Biochemical Composition Of Algae For Biofuels Production: A Review, Ankita Juneja, Ruben Michael Ceballos, Ganti S. Murthy Sep 2013

Effects Of Environmental Factors And Nutrient Availability On The Biochemical Composition Of Algae For Biofuels Production: A Review, Ankita Juneja, Ruben Michael Ceballos, Ganti S. Murthy

Biological Sciences Faculty Publications and Presentations

Due to significant lipid and carbohydrate production as well as other useful properties such as high production of useful biomolecular substrates (e.g., lipids) and the ability to grow using non-potable water sources, algae are being explored as a potential high-yield feedstock for biofuels production. In both natural and engineered systems, algae can be exposed to a variety of environmental conditions that affect growth rate and cellular composition. With respect to the latter, the amount of carbon fixed in lipids and carbohydrates (e.g., starch) is highly influenced by environmental factors and nutrient availability. Understanding synergistic interactions between multiple environmental variables and …

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Mole Street Journal, August 2013, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Sep 2013

Mole Street Journal, August 2013, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

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Arkansas Catalyst, September 2013, University Of Arkansas, Fayetteville Sep 2013

Arkansas Catalyst, September 2013, University Of Arkansas, Fayetteville

Arkansas Catalyst

No abstract provided.

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Research Frontiers, Fall 2013, University Of Arkansas Fayetteville. Office Of University Relations Sep 2013

Research Frontiers, Fall 2013, University Of Arkansas Fayetteville. Office Of University Relations

Research Frontiers

No abstract provided.

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