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Novel Separation Methods Using Electrodialysis/Electrodeionization For Product Recovery And Power Generation, Alexander Miguel Lopez-Rosa May 2015

Novel Separation Methods Using Electrodialysis/Electrodeionization For Product Recovery And Power Generation, Alexander Miguel Lopez-Rosa

Graduate Theses and Dissertations

The use of electrodialytic separations for the purification of products has been a vital technique for the past 50 years in the chemical industry. Originally used for demineralization and desalination, electrodialysis and its counterparts have expanded to assist in product purification, waste and hazard removal, and power generation. This research focused on the development of high purity organic acids purification with low power requirements. Work resulted in the development of a new type of electrodialysis process, specifically the use of ionic liquids as a secondary solvent for the development of dual solvent electrodialysis. Through dual solvent electrodialysis, ions were recovered …

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Electrostatic Atomization Of Antimicrobial Treatments On Ground Beef Processing, Instrumental Color, Sensory Color, Taste And Aroma Characteristics, Jorge Abraham Marcos May 2015

Electrostatic Atomization Of Antimicrobial Treatments On Ground Beef Processing, Instrumental Color, Sensory Color, Taste And Aroma Characteristics, Jorge Abraham Marcos

Graduate Theses and Dissertations

The general objectives of this research were to evaluate the interaction effects of sixteen different antimicrobial treatments throughout seven days of display on physical, chemical and sensory characteristics of ground beef patties, when compared to an un-treated control. Antimicrobial treatments included: fumaric acid, malic acid, octanoic acid, decanoic acid, sodium propionate, propionic acid solution, potassium lactate/diacetate blend, sodium benzoate, hexanoic acid, pyruvic acid, levulinic acid, lactic acid/ citric acid blend, sodium diacetate, lemon juice and acetic acid. Prior to grinding, beef trimmings (80/20) were electrostatically sprayed with antimicrobial treatment solutions. Ground beef was processed into meat patties and sampled for …

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A Microhabitat Assessment Of Five Species Of Invasive Plants In The Ozarks And Appalachians, Eric Hearth May 2015

A Microhabitat Assessment Of Five Species Of Invasive Plants In The Ozarks And Appalachians, Eric Hearth

Graduate Theses and Dissertations

Invasive species present a threat to native communities and their introduction and expansion can alter community structure and dynamics. Multiple approaches can be employed for invasive species management including prevention and detection. In this study, microhabitat assessments were conducted on colonies of five species of invasive plants, Alliaria petiolata (M. Bieb.) Cavara & Grande, Lespedeza cuneata (Dum. Cours.) G. Don, Lonicera japonica Thunb., Microstegium vimineum (Trin.) A. Camus, and Rosa multiflora Thunb. in the Ozark Plateau and Appalachians. Elevation, soil moisture, soil pH, light ratio, slope, aspect, distance to disturbance, as well as soil nutrient levels were recorded for each …

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Understanding The Evolution Of Aggregative Multicellularity: A Molecular Phylogenetic Study Of The Cellular Slime Mold Genera Sorodiplophrys And Pocheina, Alexander Tice May 2015

Understanding The Evolution Of Aggregative Multicellularity: A Molecular Phylogenetic Study Of The Cellular Slime Mold Genera Sorodiplophrys And Pocheina, Alexander Tice

Graduate Theses and Dissertations

Cellular slime molds are amoeboid protists that have a unicellular trophic phase and multicellular dispersal stage formed through the aggregation of individuals in their life cycles. These organisms were once thought to form a monophyletic group in the Mycetozoa. After careful morphological, ultrastructural, and molecular studies, cellular slime molds are now thought to be distantly related organisms that have all converged on the cellular slime mold habit. The following thesis consists of two molecular phylogenetic studies on two named genera of cellular slime mold for which little or no molecular data were publically available. In the first study, gene sequence …

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The Role Of Attention In Ego-Depletion, Garrett Pollert May 2015

The Role Of Attention In Ego-Depletion, Garrett Pollert

Graduate Theses and Dissertations

The resource model of ego-depletion is unable to account for the results of several ego-depletion studies, whereas a recent mechanistic revision by Inzlicht and Schmeichel (2012) has focused on the role of attention and motivation in an effort to explain the phenomenon. Assessment of attention's role in restrained and unrestrained eaters may provide evidence that motivation and attention work in tandem to affect one's ability to exert self-control. In this experiment, college-aged females participated in two studies to examine the role of attention in ego-depletion effects. Study 1 evaluated the effect of ego depletion on attention via a dot probe …

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Evaluation Of Tulane Virus As A Surrogate For The Study Of Human Norovirus, Sabastine Eugene Arthur May 2015

Evaluation Of Tulane Virus As A Surrogate For The Study Of Human Norovirus, Sabastine Eugene Arthur

Graduate Theses and Dissertations

Among all known causes of acute gastroenteritis, human noroviruses (HuNoV) are the primary cause (68%) of outbreaks and are associated with 78% of illnesses, 46% of hospitalizations, and 86% of deaths. The main obstacle to studying the pathogenesis of HuNoV is the lack of cell culture system and small animal model. Murine norovirus (MNV) and feline calicivirus (FCV) have been utilized as model surrogate viruses to study HuNoV. In this research, a more recent surrogate virus, Tulane virus (TV), was evaluated for physicochemical stability and environmental persistence. The primary goal was to determine the suitability of TV as a surrogate …

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Comparing Before-And After-School Neurocognitive Performance In High School Athletes: Implications For Concussion Management, Anderson Morgan May 2015

Comparing Before-And After-School Neurocognitive Performance In High School Athletes: Implications For Concussion Management, Anderson Morgan

Health, Human Performance and Recreation Undergraduate Honors Theses

Abstract Background: Sport-related concussion (SRC) continues be a hot topic in sports medicine. Computerized Neurocognitive Testing (CNT) provides researchers and sports medicine professionals an objective way to manage SRC. Administering CNT comes at the convenience of the student athlete and the sports medicine professional working at the school, which usually results in CNT being administered in the afternoon, or after school. However, little is known how the cognitive fatigue of attending a full day of school influences CNT performance. Purpose: The purpose of this study was to compare before school CNT performance to after school CNT performance in a sample …

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Validation Of The Tendo Weightlifting Analyzer As A Method To Assess Muscular Power, Emily Janssen May 2015

Validation Of The Tendo Weightlifting Analyzer As A Method To Assess Muscular Power, Emily Janssen

Health, Human Performance and Recreation Undergraduate Honors Theses

Power is a strong indicator of physical fitness and functional status of older adults. The Tendo Weightlifting Analyzer is a safe, cost-effective method to measure power. The goal was to validate the Tendo as a measure of muscular power during a chair stand task. It was hypothesized that the Tendo would be a valid measure. This study was a cross-sectional, correlational study with the subjects serving as their own control. All testing took place in the Human Performance Lab at the University of Arkansas. A total of 59 college-aged students from 18 to 30 years of age volunteered. Subjects were …

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Effect Of Germination And Parboiling On Milling, Physicochemical, And Textural Properties Of Medium- And Long-Grain Rough Rice, Ashley Han May 2015

Effect Of Germination And Parboiling On Milling, Physicochemical, And Textural Properties Of Medium- And Long-Grain Rough Rice, Ashley Han

Graduate Theses and Dissertations

Germinated brown rice is commonly consumed in Asia for its enhanced nutritional properties such as gamma-aminobutyric acid (GABA) and softer cooked texture. However germination decreases milling yield and alters some physicochemical properties, and most germinated rice studies evaluated medium-grain and aromatic rice cultivars. This study compared the effects of germination duration and parboiling on milling, physicochemical, and textural properties of a medium- (Jupiter) and a long-grain (Wells) rice cultivars. Rough rice was soaked in water at 25°C for 12 hr, and then incubated at 30-34°C for varying germination durations, or combined with parboiling at 120°C for 20 min prior to …

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Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin May 2015

Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin

Graduate Theses and Dissertations

Land-use change is one of the most widespread human impacts and can influence abiotic and biotic processes within surrounding streams. For example, streams in agricultural and urban watersheds receive greater light and nutrient inputs that can promote increased algal growth and primary production. Natural gas (NG) infrastructure development, a recent land use change in many regions, may also stimulate forested stream primary production, by reducing forest cover and increasing sediments and nutrient transport. I sampled streams across a NG activity gradient for algal biomass and gross primary production (GPP) to assess potential effects of this emerging land-use type. Algal biomass …

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A Comparison Of Infant And Toddler Reactions To Strangers Who Have Similar Attributes To An Established Attachment Figure Vs. Strangers Who Have Different Attributes, Jessica Hamilton May 2015

A Comparison Of Infant And Toddler Reactions To Strangers Who Have Similar Attributes To An Established Attachment Figure Vs. Strangers Who Have Different Attributes, Jessica Hamilton

Graduate Theses and Dissertations

A child's early attachment experiences can have a lasting impact on later development. Early attachment relationships often result in greater Social and cognitive skills, as well as better school performance (Peisner et al., 1999). For these reasons, it is important to address those components that may contribute to secure attachments with care givers in the child care setting. The current study looked at the reactions of infants and toddlers when presented with two previously unknown individuals: one who physically resembled an established caregiver with whom they had already established attachment and one who looked different from this caregiver. The study …

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Distinguishing Macrophage Activation States By Mass Spectrometry, Matthias Manfred Knust May 2015

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 …

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Impact Of Professional Learning Community Design On Teacher Instruction, Carol Jeanette Turner May 2015

Impact Of Professional Learning Community Design On Teacher Instruction, Carol Jeanette Turner

Graduate Theses and Dissertations

This descriptive case study closely examined a professional learning community in an Arkansas middle school. The site was selected because the school was removed from the state's school improvement list after implementing professional learning communities. The purpose of the study was to determine how the design of a professional learning community impacts teacher instruction in a middle school setting. The literature reviewed included historical perspective, definitions and characteristics of professional learning communities, teacher professional development, and teacher effect on student achievement. Eight teachers, one principal, and one instructional facilitator were interviewed about the professional learning communities in their school. The …

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The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind May 2015

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 …

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Intestinal Inflammation Model Inducing Gut Leakage By Different Methods In Broiler Chickens Using Fitc-D As A Marker, Eduardo Vicuna May 2015

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 …

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Enabling Runtime Self-Coordination Of Reconfigurable Embedded Smart Cameras In Distributed Networks, Franck Ulrich Yonga Yonga May 2015

Enabling Runtime Self-Coordination Of Reconfigurable Embedded Smart Cameras In Distributed Networks, Franck Ulrich Yonga Yonga

Graduate Theses and Dissertations

Smart camera networks are real-time distributed embedded systems able to perform computer vision using multiple cameras. This new approach is a confluence of four major disciplines (computer vision, image sensors, embedded computing and sensor networks) and has been subject of intensive work in the past decades. The recent advances in computer vision and network communication, and the rapid growing in the field of high-performance computing, especially using reconfigurable devices, have enabled the design of more robust smart camera systems. Despite these advancements, the effectiveness of current networked vision systems (compared to their operating costs) is still disappointing; the main reason …

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Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud May 2015

Phenotypic And Functional Genomics Analyses Of Salmonella For Food Safety Applications, Turki Dawoud

Graduate Theses and Dissertations

Non-typhoidal Salmonella species have been major foodborne zoonotic pathogens causing serious problems in public health and food industry for several decades. Numerous Salmonella species have frequently been associated with different food commodities mainly poultry meat, eggs, and their products. This dissertation begins with a literature reviews discussing many aspects of Salmonella generally; and subsequently focused on two serotypes, Salmonella Enteritidis and S. Typhimurium as they are at the top of all other serovars responsible for most illness cases and outbreaks. In addition, some Salmonella strains have exhibited their ability to tolerate and survive many food processing treatments. We can divide …

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Genetic Mapping Of Yield And Normalized Difference Vegetative Index In Soft Red Winter Wheat (Triticum Aestivum L.), Christopher Keith Addison May 2015

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, …

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Monitoring Abundance Of Ips Bark Beetles And Determining Related Tree Mortality In Arkansas And Texas, Chandler Stefan Barton May 2015

Monitoring Abundance Of Ips Bark Beetles And Determining Related Tree Mortality In Arkansas And Texas, Chandler Stefan Barton

Graduate Theses and Dissertations

The abundance of the southern pine engraver beetles, Ips avulsus (Eichhoff), I. grandicollis (Eichhoff), and I. calligraphus (Germar), was monitored with pheromone-baited traps in 2012 and 2013 in Arkansas and eastern Texas. Additionally, vehicle-based and comprehensive ground-based surveys were used to estimate and confirm the amount of dead and fading trees in each trapping site. Pine engraver beetles have historically been recognized as secondary invaders of healthy trees, but observations of pine mortality in Texas and Arkansas appeared to correspond with high population densities of Ips spp. Forest sites exhibiting subjectively high or low incidence of Ips-associated mortality in Arkansas …

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Distribution Of The Egyptian Goose (Alopochen Aegyptiacus) In Northwestern Arkansas And In The United States Of America, Cameron Chesbro May 2015

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 …

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Phylogeny And Diversity Of Entamoeba In Cockroaches, With An Emphasis On Periplaneta Americana, Mustafa Husain Fakhri May 2015

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 …

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Improving Production Efficiency Of Beef Cow-Calf Operations, Amanda Jo Davis May 2015

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 …

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Prediction Of Superovulatory Response In Beef Cows Based On Serum Anti-Mullerian Hormone And Antral Follicle Number, Keith Center May 2015

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 …

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Simulation In Algorithmic Self-Assembly, Jacob Hendricks May 2015

Simulation In Algorithmic Self-Assembly, Jacob Hendricks

Graduate Theses and Dissertations

Winfree introduced a model of self-assembling systems called the abstract Tile Assembly Model (aTAM) where square tiles with glues on their edges attach spontaneously via matching glues to form complex structures. A generalization of the aTAM called the 2HAM (two-handed aTAM) not only allows for single tiles to bind, but also for "supertile" assemblies consisting of any number of tiles to attach. We consider a variety of models based on either the aTAM or the 2HAM. The underlying commonality of the work presented here is simulation. We introduce the polyTAM, where a tile system consists of a collection of polyomino …

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

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

Mole Street Journal

No abstract provided.

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Commodity Of The Quarter: Quinoa: Catalyst Or Catastrophe?, Necia Parker-Gibson Apr 2015

Commodity Of The Quarter: Quinoa: Catalyst Or Catastrophe?, Necia Parker-Gibson

University Libraries Faculty Publications and Presentations

Quinoa is a grain-like crop that is rich in protein and minerals; its ability to grow on marginal soils improves its attractiveness as a potential solution to hunger in many areas. Primarily adapted to the high Andes, it is drawing increasing amounts of research scrutiny, as researchers and farmers try to create reasonable agronomic solutions to growing populations and continuing loss of arable land. Since it has become fashionable with vegetarians and vegans in the developed world, it may be argued that the crop is less available to its original growers. Issues of economic and political sovereignty complicate the use …

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2014 Northwest Arkansas Report Card, Sarah C. Mckenzie, Gary Ritter Mar 2015

2014 Northwest Arkansas Report Card, Sarah C. Mckenzie, Gary Ritter

Education Report Card

Northwest Arkansas continues to lead the state of Arkansas in K-12 education. This report card presents a regional overview as well as key performance indicators for each district. Northwest Arkansas’ public school enrollment has increased 29 percent in the past decade, and our schools have enjoyed increased racial and ethnic diversity. The 15 districts and 3 charters in Northwest Arkansas are committed to preparing students for success in college and careers. Northwest Arkansas districts continue to pursue the goal of putting their graduates in position to be successful college students, and several of them are now working to establish specialized …

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Research Frontiers, Spring 2015, University Of Arkansas Fayetteville. Office Of University Relations Mar 2015

Research Frontiers, Spring 2015, University Of Arkansas Fayetteville. Office Of University Relations

Research Frontiers

No abstract provided.

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Ansc, Spring 2015, University Of Arkansas, Fayetteville. Department Of Animal Sciences Mar 2015

Ansc, Spring 2015, University Of Arkansas, Fayetteville. Department Of Animal Sciences

Animal Science Newsletter

"Dedicated to the Alumni and Friends of the Animal Sciences Department, University of Arkansas."

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

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

Mole Street Journal

No abstract provided.

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