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The Silent Arms Race: The Role Of The Supercomputer During The Cold War, 1947-1963, David Warren Kirsch Aug 2012

The Silent Arms Race: The Role Of The Supercomputer During The Cold War, 1947-1963, David Warren Kirsch

Graduate Theses and Dissertations

One of the central features of the Cold War is the "Arms Race." The United States and the Union of Soviet Socialist republics vied for supremacy over the globe for a fifty-year period in which there were several arms races; atomic weapons, thermonuclear weapons and various kinds of conventional weapons. However, there is another arms race that goes unsung during this period of history and that is in the area of supercomputing. The other types of arms races are taken for granted by historians and others, but the technological competition between the superpowers would have been impossible without the historically …


Semiconductor Nanocrystals: From Quantum Dots To Quantum Disks, Zheng Li Aug 2012

Semiconductor Nanocrystals: From Quantum Dots To Quantum Disks, Zheng Li

Graduate Theses and Dissertations

The bottom-up colloidal synthesis opened up the possibility of finely tuning and tailoring the semiconductor nanocrystals. Numerous recipes were developed for the preparation of colloidal semiconductor nanocrystals, especially the traditional quantum dots. However, due to the lack of thorough understanding to those systems, the synthesis chemistry is still on the empirical level. CdS quantum dots synthesis in non-coordinating solvent were taken as a model system to investigate its molecular mechanism and formation process, ODE was identified as the reducing agent for the preparation of CdS nanocrystals, non-injection and low-temperature synthesis methods developed. In this model system, we not only proved …


Effects Of Head Position And Head-Supported Mass On Nerve Function Of The Flexor Carpi Radialis Muscle In Healthy Individuals, Bethany Lauren Shivers Aug 2012

Effects Of Head Position And Head-Supported Mass On Nerve Function Of The Flexor Carpi Radialis Muscle In Healthy Individuals, Bethany Lauren Shivers

Graduate Theses and Dissertations

Long-term exposure to head-supported mass (HSM) has been linked with spinal degeneration including foraminal stenosis and disc deterioration. Anecdotally, HSM has also been linked to neck and arm pain and muscle atrophy, but nerve function has not been tested specifically. The combined effect of various head positions and HSM may be sufficient to compress the nerve root in aviators and Soldiers during job performance, potentially leading to short- and long-term neuromuscular effects. The Hoffmann (H) reflex, a well-established measure of nerve function, has shown to be sensitive to changes in nerve root space which occurs with different head positions. This …


Flight Period And Species Composition Of Sirex (Hymenoptera: Siricidae) And Associated Deladenus (Nematoda: Neotylenchidae) Within Arkansas Pine Forests, Danielle Keeler Aug 2012

Flight Period And Species Composition Of Sirex (Hymenoptera: Siricidae) And Associated Deladenus (Nematoda: Neotylenchidae) Within Arkansas Pine Forests, Danielle Keeler

Graduate Theses and Dissertations

The European woodwasp, Sirex noctilio F. (Hymenoptera: Siricidae), which is a known destructive pest of pine in the southern hemisphere was recently discovered in the eastern United States. Before we can understand how S. noctilio may affect pine forests throughout the United States, we need a better understanding of native Sirex and the role they play in the ecosystem. The objectives of this research were to 1) determine species composition and flight period for native Sirex; 2) confirm presence of parasitic nematodes, Deladenus (Nematoda: Neotylenchidae), within adult Sirex; 3) investigate Deladenus parasitism rates; 4) verify the number of Deladenus species …


An Analysis Of The Redox Properties And Stability Of Chlamydomonas Reinhardtii Cytochrome F, Cytochrome C6, And Mutants Thereof, Nicole Lynn Vanderbush Aug 2012

An Analysis Of The Redox Properties And Stability Of Chlamydomonas Reinhardtii Cytochrome F, Cytochrome C6, And Mutants Thereof, Nicole Lynn Vanderbush

Graduate Theses and Dissertations

This body of work presents mutagenesis studies conducted on two c-type cytochromes from Chlamydomonas reinhardtii. Cytochrome f, a unique c-type cytochrome, is investigated in regards to its redox potential, the dependence of the redox potential, and the thermal stability of the protein. The mutations made were Y1F, Y9F, Y160F, Y160L, R156L, and R156K. The residues that were mutated surround the heme. It was found that, relative to the wild-type, only the Y160L and R156 mutants showed any difference in midpoint potential at pH 7. Wild-type and mutants both had a midpoint potential that was dependent upon pH indicating that none …


Maternal Environment And Fescue Cultivar Effects On Growth, Development, And Fertility Of Beef Heifers, Jennifer Denyse Patterson Aug 2012

Maternal Environment And Fescue Cultivar Effects On Growth, Development, And Fertility Of Beef Heifers, Jennifer Denyse Patterson

Graduate Theses and Dissertations

Eighty Brahman-influenced cows (5.6 BCS) were assigned to graze common bermudagrass (CB) or toxic tall fescue (E+) during a 60-d breeding season. Body condition (BC) was assessed at d 0, 30, and 60 of breeding season. Cows were managed to achieve marginal (4.2 BCS) or good (6.3 BCS) BC during last trimester. Heifer birth and weaning (WW; 7 to 8 mo) weights were recorded. The Angus sired heifers were weighed and randomly assigned to E+ or non-toxic (Novel) tall fescue at 9 to 10 mo of age for 190d. Heifer weight, growth data, and antral follicle count (AFC) were collected …


Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes, Aaron Russell Aug 2012

Plasmonic Pervaporation Via Gold Nanoparticle-Functionalized Nanocomposite Membranes, Aaron Russell

Graduate Theses and Dissertations

Butanol derived from biological feedstocks has significant potential as a liquid fuel source, but the separation methods used in its production can be prohibitively expensive and are therefore currently the subject of extensive research. Pervaporation is a promising membrane process that is effective in butanol separations, but involves a large energy demand. This study examines the possibility of increasing flux and energy efficiency in pervaporation via plasmonic heating of gold nanoparticle-functionalized, polymer nanocomposite membranes (AuNCMs) in lieu of conventional feed heating. An economic analysis demonstrated that plasmonic pervaporation could achieve significant reductions in energy usage and utility cost in butanol …


Determination Of Methionine And Lysine Requirements Of Growing Broilers Using The Ideal Protein Concept, Changji Lu Aug 2012

Determination Of Methionine And Lysine Requirements Of Growing Broilers Using The Ideal Protein Concept, Changji Lu

Graduate Theses and Dissertations

Three experiments were conducted to evaluate the responses of broiler performance to Lysine (Lys) and Methionine (Met) during the starter, grower, and finisher feeding phases. All the experimental diets were formulated based on the Ideal Protein Concept.

Experiment 1 evaluated the responses to Lys and Met on live performance of young broiler chickens from 0 to 18 d of age. The mean amino acid ratios to Lys suggested by literature values were used in the formulation based on the Ideal Protein Concept. Six levels of Lys and eight levels of supplemental Met were used in the diets resulting in a …


What Factors Influence Consumers' Willingness To Purchase And Consume Carbon-Labeled Rice: A Comparative Study Between Arkansas And Belgium, John A. Kelley Aug 2012

What Factors Influence Consumers' Willingness To Purchase And Consume Carbon-Labeled Rice: A Comparative Study Between Arkansas And Belgium, John A. Kelley

Graduate Theses and Dissertations

Climate change is an issue of growing importance around the globe. As global population increases so does attention focused on human contributions to climate change. One major way humans contribute to climate change is through our diets. Agricultural production is a major source of global greenhouse emissions. It has been estimated that food production is responsible for a large majority of the methane and nitrous oxide which is emitted into our atmosphere each year. Carbon footprint labeling has been developed to give consumers a way to lower their footprint and help lower emissions of greenhouse gasses. At least one retailer, …


Performing Literacy: How Women Read The World In The Late Eighteenth-Century British Novel, Amy Hodges Aug 2012

Performing Literacy: How Women Read The World In The Late Eighteenth-Century British Novel, Amy Hodges

Graduate Theses and Dissertations

This dissertation explores the intersection of sensibility, Social identity, and literacy practices among representations of women readers in four late eighteenth-century British novels. Through an analysis of the authors' use of identity constructs which shaped and were shaped by reading practices, this study documents the rise of Social identity formation as mutually constitutive with the history of reading. The first chapter reveals how Charlotte Lennox's The Female Quixote uses Arabella's follies as education for readers about the corresponding processes of reading their society and reading novels. The second chapter argues that Frances Burney's Evelina considers women's ability to read others …


The Impact Of Selected Forage Legumes On Cattle Performance, Forage Production, And Soil Quality, And Evaluation Of Legume Persistence Under Grazing, Bradley Edward Briggs Aug 2012

The Impact Of Selected Forage Legumes On Cattle Performance, Forage Production, And Soil Quality, And Evaluation Of Legume Persistence Under Grazing, Bradley Edward Briggs

Graduate Theses and Dissertations

Interest in substituting legumes for N fertilizer in beef cattle grazing systems has recently increased with rising fertilizer prices. Legumes are well known for their ability to fix atmospheric N and decrease dependence on input of N fertilizer. However, there are still difficulties associated with legume utilization including establishment and persistence. Two experiments were conducted to evaluate legume performance under herbivory. The objective of Experiment 1 was to compare forage production and beef cattle gains from annual ryegrass [Lolium multiflorum (L.)] and bermudagrass [Cynodon dactylon (L.) Pers.] pastures fertilized with N or overseeded with legumes. Gelbvieh × Angus …


The Potential Environmental Benefits Of Hybrid Rice Varieties, Haxhire Myrteza Aug 2012

The Potential Environmental Benefits Of Hybrid Rice Varieties, Haxhire Myrteza

Graduate Theses and Dissertations

With water insufficiency being already a major issue and potential carbon policies on greenhouse gas (GHG) emissions, Arkansas rice producers may need to undergo some changes in regards to rice cultivar selection. The purpose of this study is to estimate the environmental benefits of cultivating hybrid rice varieties as opposed to conventional and Clearfield rice varieties. To accomplish this goal, water use and GHG emissions were estimated on per acre (ac) and per bushel (bu) basis for most commonly cultivated rice varieties in Arkansas. The study focuses particularly on six main rice stations in the State of Arkansas. The hypothesis …


Subsurface Planetary Investigation Techniques And Their Role For Assessing Subsurface Planetary Composition, Ahmed Elshafie Aug 2012

Subsurface Planetary Investigation Techniques And Their Role For Assessing Subsurface Planetary Composition, Ahmed Elshafie

Graduate Theses and Dissertations

Subsurface planetary investigation techniques are of high interest and importance for the scientific community. Not only they can enhance our knowledge of the history of planetary formation but also can lead to information about its future. Whether the investigation is being conducted remotely using imagers, radars or physically using penetrometers or drills, a pre-existed knowledge of the mechanical and electrical properties of the subsurface regolith should be acquired for better data interpretation and analysis. Therefore, the main objective of this work is to investigate the mechanical and electrical properties of planetary analogs, understand their role for assessing the subsurface structure …


Analysis Of The Effect Of Feeding Regimen On Gh/Igf Axis In Channel Catfish (Ictalurus Punctatus), Samantha Puckett Aug 2012

Analysis Of The Effect Of Feeding Regimen On Gh/Igf Axis In Channel Catfish (Ictalurus Punctatus), Samantha Puckett

Biological and Agricultural Engineering Undergraduate Honors Theses

Channel catfish (Ictalurus punctatus) are the most widely farmed aquatic animal in the United States. Assessing the effect of feeding regimens on their overall growth requires grow-out trials and a subsequent inefficient use of time and money. The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis regulates growth based upon environmental factors such as feed intake in many teleost fish species. In order to increase the efficiency of aquaculture, the components of the GH/IGF-1 axis might be used as endocrine biomarkers to evaluate instantaneous growth rate. The goal of this study was to better understand the effects of feeding regimen on …


B.R. Wells Rice Research Studies 2011, R. J. Norman, K.A. K. Moldenhauer Aug 2012

B.R. Wells Rice Research Studies 2011, R. J. Norman, K.A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


Studies Toward The Total Synthesis Of Antascomicin B, David Ross Clay Aug 2012

Studies Toward The Total Synthesis Of Antascomicin B, David Ross Clay

Graduate Theses and Dissertations

The following dissertation describes synthetic efforts toward the synthesis of the C21-C34 fragment of antascomicin B. Our initial enzymatic approach is detailed as well as an asymmetric transfer hydrogenation (ATH) strategy that will be used in the eventual total synthesis of the molecule. Several investigations into anomalies observed during (ATH) reactions are also discussed.


Evaluation Of Internal Markers For Predicting Digestibility And Fecal Output By Cattle Fed Bermudagrass Hays Of Varying Quality, Juvenal Kanani Aug 2012

Evaluation Of Internal Markers For Predicting Digestibility And Fecal Output By Cattle Fed Bermudagrass Hays Of Varying Quality, Juvenal Kanani

Graduate Theses and Dissertations

The potential of in situ rumen undegradable dry matter (RUDM), indigestible neutral-detergent fiber (INDF), indigestible acid-detergent fiber (IADF), acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict digestibility (DMD) and fecal output (FO) by cattle fed bermudagrass [Cynodon dactylon (L.) Pers.] hay-diets categorized by their low (L), medium low (ML), medium high (MH), or high (H) CP concentrations (79, 111, 131, and 164 g/kg DM, respectively) was evaluated. The second objective was to evaluate the effects of time (0600, 1200, 1800, and 2400 h) of fecal sampling on the prediction of FO and DMD. A replicated …


Yeast Surface Display Of Cd154, Iaryna Masniuk Aug 2012

Yeast Surface Display Of Cd154, Iaryna Masniuk

Graduate Theses and Dissertations

The CD154 (CD40L) is a member of tumor necrosis factor (TNF) family that plays a crucial role in regulation of both cell-mediated and humoral immunity by activating antigen presenting cells (APCs). Previously, studies in the laboratory demonstrated that yeast surface display system allows the expression of biologically functional antigen, such as subunit HA, against influenza virus. Yeast surface display system seems to be an excellent system to be utilized to develop anti-influenza virus vaccine. Thus, it is of interest to study the adjuvant function of CD154 on the subunit HA vaccine against influenza virus. In this project, the CD154 encoding …


Water Quality Trends And Nutrient Loads For The Watershed Research And Education Center In Northwest Arkansas, 2009-2012, John Metrailer Aug 2012

Water Quality Trends And Nutrient Loads For The Watershed Research And Education Center In Northwest Arkansas, 2009-2012, John Metrailer

Graduate Theses and Dissertations

Nitrogen, phosphorus, and sediment transport is a concern for Northwest Arkansas due to high exports through riverine discharge. Urban, agricultural, and pastured watersheds have been associated with increased N, P, and sediment concentrations when compared to forested catchments. The objective of this study was to evaluate discharge and nutrient loads associated with a small urban, agricultural (row crop), wetland influenced, and pasture/farmland sub-catchment within four ephemeral drainages and located at the Watershed Research and Education Center in Fayetteville, AR. Samples were collected during base flow conditions and periodic storm flow conditions from 2009-2012. Flow adjusted concentration trends were used to …


Time Waits For No One: Using Time As A Lens In Information Systems Research, Christopher M. Conway Aug 2012

Time Waits For No One: Using Time As A Lens In Information Systems Research, Christopher M. Conway

Graduate Theses and Dissertations

Despite considerable research interest, IT projects still fail at a higher rate than other projects. Primary causes for these failures are relational, motivational, and scheduling issues on the team. Using the concept of time as a lens, the four essays in this dissertation examine how the ways that individuals and teams structure time can help explain these failures. The essays formulate the concept of temporal dissonance at the individual and team level, and explore how temporal dissonance causes negative consequences for IT workers and IT teams.

Essay one synthesizes temporal dissonance from concepts of temporal congruity and cognitive dissonance. It …


The Evolution Of Natural Plant Communities Through Crop Migration And Crop-To-Weed Gene Flow, Meredith G. Schafer Aug 2012

The Evolution Of Natural Plant Communities Through Crop Migration And Crop-To-Weed Gene Flow, Meredith G. Schafer

Graduate Theses and Dissertations

With the rising demand for food and biofuels, the efficiency of crop production has become vital to assuring food security. Genetically engineered (GE) crop varieties are broadly thought to be a solution for improving the efficiency of crop production, but concerns regarding their release have heightened as more discoveries have focused on the influence of genetically engineered crops on native and weedy plant species. Risk assessment of GE crop varieties focuses on two main areas: feralization of crop systems and crop-weed hybridization. Risks include naturalization, transgene introgression, and the formation of novel genotypes in natural systems. In this study, roadside …


Capillary-Column-Based Bioseparator/Bioreactor With An Optical/Electrochemical Detector For Detection Of Microbial Pathogens, Yanbin Li, Yongcheng Liu Jul 2012

Capillary-Column-Based Bioseparator/Bioreactor With An Optical/Electrochemical Detector For Detection Of Microbial Pathogens, Yanbin Li, Yongcheng Liu

Patents Granted

The present invention is directed to satisfying the need to detect microbial contamination of food products. The described bioseparator/bioreactor coupled with an optical/electrochemical biosensor was able to specifically detect E. coli O157:H7 from 8.8 x 10^1 to 8.8 x 10^6 CFU/ml in 2.5 hours without any enrichment. Using this invention, concentrations of S. Typhimurium ranging from 8.6 x 10^2 to 8.6 x 10^6 CFU/ml in pure culture were detected in 2 hours without any enrichment. The invention may also be used for the detection of S. Seftenberg, which has the same sensitivity as S. Typhimurium. Other pathogens such as L. …


Hr E-Source, July 2012, University Of Arkansas, Fayetteville. Human Resources Department Jul 2012

Hr E-Source, July 2012, University Of Arkansas, Fayetteville. Human Resources Department

HR e-Source

"Newsletter for staff and faculty at the University of Arkansas."


Mole Street Journal, June 2012, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry Jul 2012

Mole Street Journal, June 2012, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.


Cultivatingbigideas, July 2012, University Of Arkansas, Fayetteville. Technology Development Foundation Jul 2012

Cultivatingbigideas, July 2012, University Of Arkansas, Fayetteville. Technology Development Foundation

Cultivating Big Ideas

No abstract provided.


Institutional Research…Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Office Of Institutional Research Jun 2012

Institutional Research…Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Office Of Institutional Research

Office of Institutional Research and Assessment Annual Report

No abstract provided.


Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Graduate School And International Education Jun 2012

Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Graduate School And International Education

Graduate School and International Education Annual Report

No abstract provided.


Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Office Of The Vice Provost For Research And Economic Development Jun 2012

Annual Report, 2011-2012, University Of Arkansas, Fayetteville. Office Of The Vice Provost For Research And Economic Development

Research and Innovation Annual Report

No abstract provided.


Faculty Publications & Presentations, 2011-2012, University Of Arkansas, Fayetteville Jun 2012

Faculty Publications & Presentations, 2011-2012, University Of Arkansas, Fayetteville

Faculty Publications and Presentations

No abstract provided.


Annual Report, 2011, University Of Arkansas, Fayetteville. J. William Fulbright College Of Arts And Sciences. King Fahd Center For Middle East Studies Jun 2012

Annual Report, 2011, University Of Arkansas, Fayetteville. J. William Fulbright College Of Arts And Sciences. King Fahd Center For Middle East Studies

King Fahd Center for Middle East & Islamic Studies Annual Report

Program Director: Tom Paradise, 2005-2009; Joel Gordon, 2009-