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Characterization And Quantification Of Monomers, Oligomers, And By-Products From Switchgrass Hemicelluloses During Biomass Pretreatment, Kris Allan Bunnell

Graduate Theses and Dissertations

Production of fuels and chemicals from biomass is contingent upon economical release of carbohydrates from biomass. Carbohydrates can then be used for production of bio-based products using a biochemical conversion process. Pretreatment, the first step of the biochemical conversion process, has been suggested to be the most costly step of the conversion process. Thus, better understanding the behavior of biomass during pretreatment is imperative for an economically viable production of biofuels and chemicals. Elucidating the physicochemical properties of biomass and developing an understanding the depolymerization patterns of biomass during pretreatment will help progress towards this goal.

In this study, July- …

"An Easy Switch": A Descriptive Case Study Exploring The Shift Toward Informational Text Accompanying The Implementation Of Common Core State Standards In Five Primary Classrooms, Heather Denise Kindall

Graduate Theses and Dissertations

The purpose of this descriptive case study was to discover how the newly implemented Common Core State Standards (CCSS) may have changed teachers' practices and philosophies regarding literacy instruction and to determine which teaching strategies were being presented in regard to informational text in the studied Kindergarten through second grade classrooms.

The research was conducted in five classrooms within one elementary school in the mid-Southern United States. The study design involved semi-structured interviews, classroom observations, and teacher-reported lesson plans over a fourteen week data collection period. The aim of this research was to portray a vivid description of the implementation …

Nonprofit Board Members' Self-Perception In The Role Of Organizational Governance And The Balanced Scorecard, Jeffrey John Aulgur

Graduate Theses and Dissertations

This qualitative case study examines the gap between expectations of board performance held by the senior leadership and the governing board's self-perception of their role in the governance of the nonprofit organization. The primary research question is: Is an analysis of the gap between governance expectations and the board members' self-perception of governance performance an effective methodology for enhancing the efficacy of the governing board of directors? Nonprofit governance and its effectiveness are difficult concepts to define, given the wide disparity in organizational sizes, structures, and missions. While the academic literature does not identify a dominant methodology for organizational effectiveness …

Analysis Of Parameter Tuning On Energy Efficiency In Asynchronous Circuits, Justin Thomas Roark

Graduate Theses and Dissertations

Power and energy consumption are the primary concern of the digital integrated circuit (IC) industry. Asynchronous logic, in the past several years, has increased in popularity due to its low power nature. This thesis analyzes a collection of array multipliers with different parameters to compare two asynchronous design paradigms, NULL Convention Logic (NCL) and Multi-Threshold NULL Convention Logic (MTNCL). Several commercially available pieces of software and custom scripts are used to analyze the asynchronous circuits and their components to provide the energy consumption estimation on various parts of each circuit. The analysis of the software results revealed that MTNCL circuits …

Interest Group Scorecards And Legislative Satisfaction: Using Ratings To Explore The Private Bias In Public Policy, Daniel E. Chand

Graduate Theses and Dissertations

Despite their importance to our system, the study of interest groups has produced few concrete findings compared to other actors such as administrative agencies and political parties in the policymaking process. The absence of generalizable findings is partly explained by the unpopularity of the topic, but is primarily due to a deficiency of easily accessible data and lack of agreement over how to operationalize important concepts. In the following dissertation, I employ interest group "scorecards" (ratings of members of Congress) as an approach to examining interest groups in a generalizable manner. Specifically, I use scorecards to test the pluralist assumptions …

Fabrication Of Tungsten Tips Suitable For Scanning Probe Microscopy By Electrochemical Etching Methods, Gobind Basnet

Graduate Theses and Dissertations

The fabrication of metal tips is becoming an interesting field for scientists who are working in spectroscopy measurements. A significant amount of work has already been done in the tips fabrication process. Metal tips used to analyze the surface of materials play a key role in the scanning tunneling microscope (STM) technique. It's remarkable quality that it is used to study the surface of material at the atomic level.

There are various methods used in the tips fabrication process. Of diverse methods, three different electrochemical etching methods: submerged method, single lamella drop-off method, and double lamella drop-off method are commonly …

System Design And Motion Artifact Removal Algorithm Implementation For Ambulatory Women Ecg Measurement System:E-Bra System, Hyeokjun Kwon

Graduate Theses and Dissertations

Cardio Vascular Disease (CVD) leads to sudden cardiac death due to irregular phenomenon of the cardiac signal by the abnormal case of blood vessel and cardiac structure. For last three decades, there is an enhanced interest in research for cardiac diseases.. As a result, the death rate by cardiac disease in men has been falling gradually compared with relatively increasing the death rate for women due to CVD. The main reason for this phenomenon is due to the lack of seriousness to female CVD and different symptoms of female CVD compared with the symptoms of male CVD. Usually, because the …

Genome-Wide Association Mapping Identifies Qtls And Candidate Genes For Salt Tolerance In Soybean, Lei Huang

Graduate Theses and Dissertations

Salinity is a common abiotic stress causing soybean yield loss worldwide. Use of tolerant cultivars is an effective and economic approach to coping with this stress. Toward this, research is needed to identify salt-tolerant germplasm and better understand the genetic and molecular basis of salt tolerance in soybean. The objectives of this study were to identify salt-tolerant genotypes, to search for SNPs and QTLs associated with salt tolerance, and to identify candidate salt tolerance genes. A total of 192 diverse soybean lines and cultivars were screened for salt tolerance in the greenhouse based on visual leaf scorch scores after 15 …

Modeling Chemical Reactions In Aqueous Solutions, Osman Uner

Graduate Theses and Dissertations

The energy barriers for SN2 ligand exchange reactions between the chloride anion and para-substituted benzyl chlorides were investigated both in water solution and in the gas phase by using quantum chemical simulations at the DFT and Hartree-Fock levels. The question addressed was the effect of the solvent (water) and of the substituent on the barrier height. The para substitutient groups included NH2, OH, OCH3, CH3, C(CH3)3, H, F, Cl, Br, I, CF3, CN, NO2, and SO3- . The calculations in aqueous solution were carried out with the recently developed Ultrafast Monte Carlo method using the TIP3P explicit water model. The …

Evaluation Of Water Sanitation Options For Poultry Production, Pramir Maharjan

Graduate Theses and Dissertations

An evaluation of poultry farm water supplies was conducted to determine the value and impact of water system sanitation practices in commercial broiler houses on microbial levels. Water line cleaning between flocks using concentrated disinfectant solution before placing chicks reduced biofilms retained in the lines to a safe level. Occasional microbial surges were noticed during different points of flock grow-out period even when daily water sanitation was present indicating water is highly susceptible to microbial contamination. However, the daily water sanitation practice controlled the occasional microbial surges in water from sustaining and kept drinking water to a microbiologically acceptable level. …

The Word Problem For The Automorphism Groups Of Right-Angled Artin Groups Is In P, Carrie Anne Whittle

Graduate Theses and Dissertations

We provide an algorithm which takes any given automorphism f of any given right-angled Artin group G and determines whether or not f is the identity automorphism, thereby solving the word problem for the automorphism groups of right-angled Artin groups. We do this by solving the compressed word problem for right-angled Artin groups, a more general result. A key piece of this solution is the use of Plandowski's algorithm. We also demonstrate that our algorithm runs in polynomial time in the size of the given automorphism, written as a word in Laurence's generators of the automorphism group of the given …

Mitigating Shrinkage Cracking Of Concrete In Bridge Decks Through Internal Curing, Daniel Robert Goad

Graduate Theses and Dissertations

As the need for durable, long lasting infrastructure increases, new methods and techniques are being explored to prolong the service life of roads and bridges. One method to reduce shrinkage and early age cracking in concrete is internal curing. Internal curing supplies water to concrete, using pre-wetted lightweight aggregate (LWA), as needed throughout the process of hydration to reduce self desiccation, which leads to cracking. This research project analyzed two types of coarse LWA, expanded clay and expanded shale. The mixtures were developed specifically for use in bridge decks and adhered to specifications of the Arkansas State Highway and Transportation …

Variability In The Hydraulic Conductivity Of A Test Pad Liner System Using Different Testing Techniques, Matthew Jonathan Nanak

Graduate Theses and Dissertations

Historic methods (the time lag approach, the velocity approach, and the Z-t approach), utilized to reduce two stage borehole test data, were evaluated. Two of the historic methods provided viable results and were used for this research project. Additionally, these two methods are recommended for reducing two stage borehole test data in the future.

Flexible wall permeameter and soil index laboratory testing were conducted on the soil used to construct three environmentally controlled compacted clay liners (test pads) to develop a zone of acceptance (placement window). Using the results from the laboratory testing, two acceptance criterions were evaluated, while one …

Biodiesel Transesterification Byproducts As Soil Amendments, Solomon Parker

Graduate Theses and Dissertations

For every ten kilograms of biodiesel that is produced from the transesterification of vegetable oil, approximately 1 kg of glycerol is produced as a byproduct. Also known as glycerin, it is a chemical used in many products including cosmetics, foods, and desiccants. However, the crude glycerol created during biodiesel production is tainted with potassium hydroxide and methanol making it unsuitable for commercial use without costly refinement. With increase in production of biodiesel driven by rising fuel prices, the market has become glutted with glycerol and it is on the threshold of becoming a waste product. Common methods for disposing glycerol …

Toile, Dilenia Garcia

Graduate Theses and Dissertations

Toile is a painting series that explores constructions of taste and the semiotics of manufactured fabrics. Through the use of irony, paradox and deconstructions of rhythm, shape, color and form, the paintings are a response to the formal and historical content in the fabric. The idyllic landscape, notions of identity, sexism and liminality are some of the themes considered in the series. The paintings in this exhibition attempt to correct and mediate outdated models of representation through the exploration of painting as a process that is open and malleable.

Using The Ceres-Maize Model To Create A Geographically Explicit Grid Based Estimate Of Corn Yield Under Climate Change Scenarios, Ryan Zachary Johnston

Graduate Theses and Dissertations

The CERES-Maize model was evaluated in its capacity to predict both regional maize yield and water use within the United States Department of Agriculture (USDA) Economic Research Service (ERS) Region 1 between the years 1997-2007. A grid based, geospatially explicit method was developed to express the various rainfed and irrigated maize cultivars grown across the region. Overall, the calibrated model compared well for both physiological and yield parameters, producing significant linear relationships (p

The calibrated and validated CERES-Maize model was used to predict potential evapotranspiration and yield under three IPCC weather scenarios for the year 2050 to evaluate crop production …

Return To Traffic Of Full Depth Reclamation Pavements, Robert Benjamin Hill

Graduate Theses and Dissertations

Full-Depth Reclamation (FDR) is a cost-effective rehabilitation treatment for deteriorated pavements. However, when using asphalt emulsion based rehabilitation techniques one of the most challenging aspects of FDR is determining when traffic can be returned to the rehabilitated pavement surface. Since asphalt emulsion mixtures need ample time for curing, they cannot be sealed with a surface layer until the water has evaporated from the rehabilitated layer. It is often not possible to keep the road closed until all of the water has evaporated and the surface layer is placed, therefore, at some point the traffic needs to be returned to the …

Bio-Separation Process Improvement Via Genomic Manipulation: Development Of Novel Strains For Use In Immobilized Metal Affinity Chromatography (Imac), Ryan Curtis Haley

Graduate Theses and Dissertations

The dissertation is comprised of three parts. Part I describes proteomic analysis of native bacterial proteins from Escherichia coli (E.coli) that bind during Immobilized Metal Affinity Chromatography (IMAC). Part II describes the value in exploiting proteome based data as a tool toward the design an E. coli expression strain that is particularly useful when Immobilized Metal Affinity Chromatography is employed as the initial capture step of a homologous protein purification process. Part III describes a methodology of chromosomal mapping of all contaminant gene products.

The objective of Part I was to identify all E. coli proteins that bind to Co(II), …

The Adair Site: Ouachita River Valley Relations Through Ceramic Analysis, Joanne Demaio

Graduate Theses and Dissertations

The Adair site (3GA1), located in the Upper Ouachita River Valley in Garland CO, Arkansas is an Upper Ouachita Caddo site. The people at the site are presumed to be at the center of cultural dominance for the area and had interaction with Caddo sites in the region. This thesis explores this by studying the whole vessel collections that were excavated at the Adair site in the 1930s. Comparing the Adair collection to three other Caddo sites provides information about the Social standing of the Adair site, its relations with other sites, and how it fits into the greater fabric …

Archaeological Prospecting Using Historic Aerial Imagery: Investigations In Northeast And Southwest Arkansas, Emily Jean Bitely

Graduate Theses and Dissertations

This research investigates the potential of historic aerial photographs as a tool for archaeological site prospecting. Craighead and Mississippi Counties in northeast Arkansas and areas adjacent to the Red and Little Rivers in southwest Arkansas were chosen as study areas. These regions have undergone significant changes in the past few decades and were expected to yield visible types of archaeological sites. Historic aerial images of these areas were obtained through the U.S. Geological Survey's EarthExplorer database (http://earthexplorer.usgs.gov/). These images were processed using Agisoft PhotoScan Professional to produce extensive regional orthoimages.

Using the Arkansas Archeological Survey's Automated Management of Archeological Site …

Dark Green Color Index As A Method Of Real-Time In-Season Corn Nitrogen Measurement And Fertilization, Upton Siddons

Graduate Theses and Dissertations

Corn (Zea mays L.) requires higher rates of nitrogen fertilizer than any other major U.S. crop partly because N fertilizers are subject to loss through various mechanisms. Because of this, corn may suffer from inadequate nitrogen fertilization or producers may over-apply nitrogen to compensate for early-season nitrogen losses. A timely, accurate, and precise method for measuring in-season corn N status is needed to allow producers to keep nitrogen use efficiency high within a growing season.

Using appropriate software, hue, saturation, and brightness values of digital images can be combined in a dark green color index (DGCI) which is closely associated …

Subtle Messages: An Examination Of Diversity In The Illustrations Of Secondary Level One French Textbooks, Stephen Richard Adamson

Graduate Theses and Dissertations

Textbooks in all content areas have been criticized for the hidden curriculum that subtly teaches messages, which elevate some cultural groups while diminishing the efforts and contributions of other cultural groups. Research into the hidden curriculum and inclusion of diversity in French textbooks has been limited. The present study focused on the inclusion of diversity in terms of race/ethnicity, gender, socioeconomic status, disability, and body size present in the illustrations of the three newest French One textbooks. Results indicate that diversity has increased but the diversity within the illustrations does not always mirror the actual demographics of the United States …

Does Emotion Invalidation Cause Emotion Dysregulation? Evidence From A Healthy Sample Of College Students And Implications For The Development Of Borderline Personality Disorder, Melissa Jean Zielinski

Graduate Theses and Dissertations

Linehan's BioSocial theory is a widely accepted model of the development of borderline personality disorder (BPD). However, the tenet that experiences of invalidation causally influence the development of the emotion dysregulation that characterizes BPD has been subject to relatively little empirical attention. The purpose of this study thus was to experimentally investigate the effects of validation and invalidation on indices of emotion dysregulation including self-invalidation, distress tolerance, and Social problem solving. The current study used a laboratory-based emotion induction procedure in which ninety college students participated in validating or invalidating conversations about emotional events with a peer confederate. Contrary to …

Active Galactic Nuclei Mergers And Outflows: Observations From Optical And Ultraviolet Emission Lines, Robert Scott Barrows

Graduate Theses and Dissertations

I have investigated the nature of a subset of active galactic nuclei (AGN) which show double peaks in their characteristic optical and ultraviolet emission lines. I have performed this investigation through studies of the broad emission line regions (BLRs), which are produced less than 1 pc from the central supermassive black hole (SMBH), and the narrow emission line regions (NLRs), which originate at larger (kpc) distances. The BLR studies consist of detailed line modeling of two individual quasars with double-peaked broad emission line profiles. The modeling suggests there are two primary interpretations of the complex broad line profiles. The first …

An Analysis Of Firearms Training Performance Among Active Law Enforcement Officers, John Thomasson

Graduate Theses and Dissertations

Firearms proficiency is an implicit expectation, held by the public of police officers, due to presumption that the required firearm training is an adequate preparation for a deadly force encounter. However, anecdotal evidence and available data on police shootings suggest that conventional, unrealistic training methods are wholly inadequate. To present stress into firearms training, some departments have opted for exercises such as physical exertion and shoot-house training as a substitute for realistic simulation of force-on-force confrontations.

To determine whether such exercises are comparable, an observation of performance and heart rate levels was conducted on a group of eight police officers, …

Local Food And Agriculture Awareness: The Literacy Of Local Produce And Agriculture In Northwest Arkansas, Kyle Colton Flynn

Graduate Theses and Dissertations

The Center for Disease Control and Prevention (CDC) suggests that adolescents and children, both male and female, are failing to meet the daily fruit and vegetable consumption requirements (Kim et al., 2011; Upton et al., 2012; Harris et al., 2012). Other studies have shown that with increased exposure and availability of produce, students (K-5) tend to consume more fruits and vegetables (Cullen et al., 2009; Evans et al., 2012). The purpose of this study is to identify whether Northwest Arkansas eleventh grade high school students possess experience and knowledge of local produce and agriculture. Out of 1054 students enrolled at …

Gesture Based Home Automation For The Physically Disabled, Alexander Hugh Nelson

Graduate Theses and Dissertations

Paralysis and motor-impairments can greatly reduce the autonomy and quality of life of a patient while presenting a major recurring cost in home-healthcare. Augmented with a non-invasive wearable sensor system and home-automation equipment, the patient can regain a level of autonomy at a fraction of the cost of home nurses. A system which utilizes sensor fusion, low-power digital components, and smartphone cellular capabilities can extend the usefulness of such a system to allow greater adaptivity for patients with various needs. This thesis develops such a system as a Bluetooth enabled glove device which communicates with a remote web server to …

Battle Mound: Exploring Space, Place, And History Of A Red River Caddo Community In Southwest Arkansas, Duncan Mckinnon

Graduate Theses and Dissertations

This research is a synthesis of archaeogeophysical and archaeohistorical data collected from the Battle Mound site (3LA1). Using these data, this research seeks to understand how the site is organized in terms of architectural variability and how differential use areas, such as domestic or community space, can be compared to ethnographic and archaeological data concerning Caddo community structure and landscape use. The research is formulated around three research questions related to spatial organization and settlement patterning, intrasite behavioral practices, and Caddo culture history. Results show that an examination at multiple scales of resolution can inform about the spatial organization and …

Classification Of Satellite Time Series-Derived Land Surface Phenology Focused On The Northern Fertile Crescent, Brian Embree Bunker

Graduate Theses and Dissertations

Land surface phenology describes events in a seasonal vegetation cycle and can be used in a variety of applications from predicting onset of future drought conditions, to revealing potential limits of historical dry farming, to guiding more accurate dating of archeological sites. Traditional methods of monitoring vegetation phenology use data collected in situ. However, vegetation health indices derived from satellite remote sensor data, such as the normalized difference vegetation index (NDVI), have been used as proxy for vegetation phenology due to their repeated acquisition and broad area coverage. Land surface phenology is accessible in the NDVI satellite record when images …

Learning Experiences And Perspective Transformation In Evangelical Faith-Based Adult Nonformal Education Programs, Philip Gerke

Graduate Theses and Dissertations

The study adapted an existing instrument to examine perspective transformation and its associated factors in participants of evangelical faith-based adult nonformal education in the Midwestern United States. Stratified random one-stage cluster sampling of 11 churches produced a nonprobability sample (N = 597) that was significantly (p < .05) different from the population of the geographical location of the study. An 86% majority self-reported a level of agreement or stronger of perceived transformation of perspectives, but differences predicted by gender were insignificant. The difference in perceived perspective transformations between respondents aged 40-59 that had the highest levels and respondents aged 60 and above that had the lowest levels was significant. The factors of influential individuals, personal reflection, and thought-provoking learning assignments significantly predicted all four factors of perspective transformation; the Writing Assignment factor was a significant negative predictor of only the Perception of Change factor, and a significant positive predictor of only the Future Benefits factor. The study recommended that additional research on faith-based frames of reference and age category differences. The study also recommended that faith-based practitioners consider emphasizing transformative learning experiences and personal reflection in their programs for adults.