Digital Commons Network^™

Knowledge, Perceptions, And Outcomes Of Agricultural Communications Curriculum In Arkansas Secondary Agricultural Classrooms, Carley Payne Calico

Graduate Theses and Dissertations

The purpose of this mixed method study was to assess the effectiveness of agricultural communications curriculum developed and incorporated into a semester-long agricultural leadership and communications course for secondary agricultural education programs in Arkansas. This study was comprised of three parts including a pilot test, teacher training assessment, and a descriptive field test over a two-year period. For the pilot test portion of the study, students (N = 297) participated in newly developed instructional modules (careers, writing, design, and multimedia) predetermined by a committee of agricultural education and communications faculty at the University of Arkansas. The pilot test indicated students' …

Properties Of Multiferroic Bifeo3 From First Principles, Dovran Rahmedov

Graduate Theses and Dissertations

In this dissertation, a first-principle-based approach is developed to study magnetoelectric effect in multiferoic materials. Such approach has a significant predictive power and might serve as a guide to new experimental works. As we will discuss in the course of this work, it also gives an important insight to the underlying physics behind the experimentally observed phenomena.

We start by applying our method to investigate properties of a generic multiferroic material. We observe how magnetic susceptibility of such materials evolves with temperature and compare this evolution with the characteristic behavior of magnetic susceptibility for pure magnetic systems. Then we focus …

Detailed Inventory Record Inaccuracy Analysis, Hayrettin Kaan Okyay

Graduate Theses and Dissertations

This dissertation performs a methodical analysis to understand the behavior of inventory record inaccuracy (IRI) when it is influenced by demand, supply and lead time uncertainty in both online and offline retail environment separately. Additionally, this study identifies the susceptibility of the inventory systems towards IRI due to conventional perfect data visibility assumptions. Two different alternatives for such methods are presented and analyzed; the IRI resistance and the error control methods. The discussed methods effectively countered various aspects of IRI; the IRI resistance method performs better on stock-out and lost sales, whereas error control method keeps lower inventory. Furthermore, this …

The Efficacy Of Probiotic Bacterial Isolates In Reducing Cecal Camylobacter Colonization In Broiler Chickens, Komala Arsi

Graduate Theses and Dissertations

Campylobacter is the leading cause of foodborne illness worldwide and human illnesses are often associated with consumption of poultry or poultry products. Many strategies have been tried to eliminate Campylobacter from poultry with limited success. One of the strategies to reduce Campylobacter colonization in poultry is by use of probiotics. We conducted 2 separate studies to evaluate the efficacy of probiotics against Campylobacter in broiler chickens. For our first study, GRAS (Generally Regarded as Safe) bacteria were isolated from healthy chickens and tested their efficacy against Campylobacter in vitro. Twenty six isolates with in vitro anti-Campylobacter activity were …

Efficient Ray Tracing For Mobile Devices, Rafael De Melo Aroxa

Graduate Theses and Dissertations

The demand for mobile devices with higher graphics performance has increased substantially in the past few years. Most mobile applications that demand 3D graphics use commonly available frameworks, such as Unity and Unreal Engine. In mobile devices, these frameworks are built on top of OpenGL ES and use a graphics technique called rasterization, a simple concept that yields good performance without sacrificing graphic quality. However, rasterization cannot easily handle some physical phenomena of light (i.e. reflection and refraction). In order to support such effects, the graphics framework has to emulate them, thereby leading to suboptimal results in term of quality. …

The Danielson Evaluation System In Two Mid- South High Schools: A Case Study, Laura R. Strickland

Graduate Theses and Dissertations

The purpose of this study is to answer the question: How do pilot users of the Danielson Evaluation System perceive this model in two mid-south high schools? The study describes the perceptions of teachers and administrators who implemented the Danielson Teacher Evaluation Model. The primary focus was on teachers and administrators experience with the pilot of the new Arkansas Teacher Excellence Support System. In an effort to meet requirements under the ESEA flexibility waiver Arkansas developed a comprehensive evaluation model to meet state and federal accountability standards. Arkansas Department of Education developed a pilot school program in which they were …

Depositional History And Stratigraphic Framework Of Upper Cretaceous (Campanian To Maastrichtian) Strata In The Minerva-Rockdale Oil Field Of Milam County And Adjacent Counties, Texas., Adam Thomas Martin

Graduate Theses and Dissertations

First discovered in 1921, the Minerva-Rockdale Oil Field (MROF) has experienced a recent resurgence of drilling. The targeted Navarro Group is Upper Cretaceous (Maastrichtian) in age and ranges in depth from approximately 100 to 3000+ ft. (subsea). Several thin elongated sandy zones within the Kemp clay of the Corsicana (Navarro) Formation, are the current targets for oil production. These sandy zones are informally divided into the Navarro `A' and `B' and their depositional morphology is described by the shelf plume model, as proposed by Patterson (1983).

Despite the mature nature of the MROF and surrounding area, only a small number …

Web Accessibility Of The Higher Education Institute Websites Based On The World Wide Web Consortium And Section 508 Of The Rehabilitation Act, Najma Habib Alam

Graduate Theses and Dissertations

The problem observed in this study is the low level of compliance of higher education website accessibility with Section 508 of the Rehabilitation Act of 1973. The literature supports the non-compliance of websites with the federal policy in general. Studies were performed to analyze the accessibility of fifty-four sample web pages using automated testing via auto-validation tools and using manual testing via assistive technology, followed by a comparative analysis of the findings of the auto validation tools. The auto-validation tools utilized on the sample web pages were comprised of three W3C validation tools. The results showed that two-thirds of the …

Hope, Faith And Trust: Conversations With Tibetans In Exile, William Lukas Gramlich

Graduate Theses and Dissertations

The goal of Hope, Faith and Trust: Conversations with Tibetans in Exile was to create a documentary to serve as a platform for Tibetan refugees living in India to tell, in their own words, the story of the Tibetan peoples' political struggles since the Chinese government occupied Tibet in the 1950s. To achieve this goal, this project utilized oral-history interviews with Tibetan exiles, gathered as part of the University of Arkansas TEXT Program. The TEXT Program, short for Tibetans in Exile Today, is a study abroad oral-history project in which undergraduate students conduct interviews with Tibetans living in India. The …

Structure And Stratigraphy Of A Complex Anticlinal Feature, Backbone Anticline, Arkoma Basin, Arkansas, Shailyn Marie Abbott

Graduate Theses and Dissertations

The Arkoma Basin of Arkansas and Oklahoma formed in the Ouachita foreland during the late Mississippian and Pennsylvanian periods (about 290-to 330 million years ago). The basin developed in response to convergent tectonic boundaries that closed obliquely from west to east associated with Ouachita orogenic event. The Backbone anticline in the northern Arkoma Basin is a prominent product of this convergence, and represents the first major component of this study. The structure is asymmetric with beds on the southern limb dipping steeply to the south. It is also expressed topographically as a prominent ridge that trends eastward from the Oklahoma-Arkansas …

Porosity Development Within Lobes To Downslope Ramp Deposits On A Prograding Carbonate Shelf Of The Kinderhookian To Osagean Series In Northwest Arkansas, Elizabeth Marchese

Graduate Theses and Dissertations

Carbonate bodies with lobate geometries form a substantial part of the Osagean (early Mississippian) section in northwest Arkansas. The purpose of this study is to isolate and describe a single lobe from three-dimensional exposures in quarry walls to provide criteria by which lobe and lobe porosity can be recognized in the subsurface. Carbonate sediment generated on the Mississippian Burlington shelf moved southward by gravity flows from the shelf margin to positions on a prograding ramp in Arkansas where overlapping deposits with lobate geometries accumulated. These deposits are recognized in outcrops of the Boone Formation. Stratigraphic units within the Boone are …

Structural And Stratigraphic Transition From The Arkoma Shelf Into The Arkoma Basin During Basin Subsidence; Arkoma Basin, Northwest Arkansas, Elizabeth Whitney Studebaker

Graduate Theses and Dissertations

The Arkoma basin is an arcuate Paleozoic structural feature in the Ouachita foreland that extends from central Arkansas and westward into southeastern Oklahoma. The Arkoma shelf lies immediately north of the basin and is comprised of Cambrian to Pennsylvanian age sedimentary rocks. In northwestern Arkansas, the stratigraphic and structural transition from the shelf into the northern portion of the Arkoma basin is poorly defined.

Wireline logs were used to construct a series of three north to south cross sections, as well as two along-strike west to east cross sections to examine Morrowan and lower Atokan age strata. In addition to …

Factors Influencing The Academic Achievement And Success Of African American Male Principals In A Midsouth State, Roy C. Turner

Graduate Theses and Dissertations

A consistent pattern of academic failure among African American (AA) males in our nation's schools has generated a great deal of interest among educational researchers and practitioners. In fact, some studies show that AA males have been labeled as an endangered species. In an effort to reduce this dangerous negative trend, more research needs to be conducted to uncover those factors that contribute to AA males' academic achievement. This study will investigate factors (motivation, parental involvement/family and peer influence, environmental, or social factors) that may have contributed to the academic achievement of AA male principals who have achieved success by …

Atomic-Scale Characterization And Manipulation Of Freestanding Graphene Using Adapted Capabilities Of A Scanning Tunneling Microscope, Steven Barber

Graduate Theses and Dissertations

Graphene was the first two-dimensional material ever discovered, and it exhibits many unusual phenomena important to both pure and applied physics. To ensure the purest electronic structure, or to study graphene's elastic properties, it is often suspended over holes or trenches in a substrate. The aim of the research presented in this dissertation was to develop methods for characterizing and manipulating freestanding graphene on the atomic scale using a scanning tunneling microscope (STM). Conventional microscopy and spectroscopy techniques must be carefully reconsidered to account for movement of the extremely flexible sample.

First, the acquisition of atomic-scale images of freestanding graphene …

3d Seismic Mapping Of Probable Tripolitic Chert Bodies In Osage County, Oklahoma, Richard Craddock Benson

Graduate Theses and Dissertations

The Mississippi Lime play is an important recent oil and gas development in the mid-continent of the United States. In April of 2007, Chesapeake Energy Corporation used horizontal drilling and tracing to bring the Howell 1-33H well online. This well revitalized the Mississippi Lime play, expanding exploration with potential Mississippian reservoirs.

The Mississippian section is a complex carbonate reservoir containing several distinct lithologies. An important Mississippian lithology known from outcrops in Arkansas and Missouri is tripolitic chert, or tripolite; a bleach, highly diagenetically altered, silica rock with high porosity, low density, and high permeability. Tripolite is an important reservoir target …

Differential Extinction Of Disgust And Anxiety Among Victims Of Sexual Traumatization, Christal Badour

Graduate Theses and Dissertations

Emerging evidence suggests that in addition to fear, traumatic event-related disgust reactions may be integral to understanding the sequelae of sexual traumatization. Importantly, evidence broadly suggests compared to fear, disgust may be resistant to extinction. As such, conditioned disgust reactions may not evidence the same pattern of extinction observed with fear-based reactions. This may have important implications for the treatment of posttraumatic stress disorder (PTSD). As such, the current study sought to fill an important gap in the existing literature by examining specific processes and mechanisms that are likely to affect outcomes of exposure-based interventions following sexual traumatization. Specifically, 72 …

Assessment Of The Predictive Reliability Of A Swat Flow Model And The Evaluation Of Runoff Generation And Bmp Effectiveness In A Shale-Gas Impacted Watershed Using A Modeling Approach, Kwasi Asante

Graduate Theses and Dissertations

In order to ensure a harmonious harness of shale-gas resources while ensuring minimal damage to the environment, it is imperative that studies to conduct to inform various aspects of managing the environment. This includes the development of reliable hydrologic models to inform in decisions concerning water and the environment.

The first objective of this study was to evaluate the predictive reliability of the Soil and Water Assessment Tool (SWAT) model based on respective methods of LULC data classification and data type spatial resolution. Results showed that the high-resolution data classified with object-oriented image method does not provide any significant advantage …

Assessing Trichloromethane Formation And Control In Algal-Stimulated Waters Amended With Nitrogen And Phosphorus, Clinton Mash

Graduate Theses and Dissertations

Nitrogen (N) and phosphorus (P) enrichments can stimulate algal growth in drinking water sources, which can cause increased production of disinfection byproduct (DBP) precursors. However, the effect of systematic N and P enrichments on DBP formation and control has not been adequately studied. In this work, we enriched samples from a drinking water source - sampled on April 5, May 30, and August 19, 2013 - with N and P to stimulate algal growth at N:P ratios covering almost five orders of magnitude (0.2-4,429). To simulate DBP-precursor removal processes at drinking water treatment plants (DWTPs), the samples were treated with …

Assessing The Impact Of Chlorine Residual On Trihalomethane And Haloacetonitrile Formation Under Chlorination And Chloramination Disinfection Regimes, Thien Duc Do

Graduate Theses and Dissertations

A disinfection byproduct (DBP) formation potential (FP) test can be used to indirectly measure the concentration of DBP precursors in natural waters, permitting assessment of various DBP-related treatment processes and control strategies. While these tests require a 7-day chlorine residual (CR) between 3-5 mg L^-1 as Cl², it is not well known if this recommended residual corresponds to the true DBPFP (i.e., the maximum concentrations) for trihalomethanes (THMs) and haloacetonitriles (HANs). In this study, THMs and HANs were quantified as a function of CR under three common disinfection regimes: (1) free chlorine at pH 7.0 (FC7), (2) …

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 …

Environmental Literacy Of Sixth Grade Students In Arkansas: Implications For Environmental Education Reform, Lisa Suzanne Wood

Graduate Theses and Dissertations

Environmental education must be better integrated into K-12 curriculum to advance environmental literacy. Producing a citizenry that can understand and address the complex environmental issues facing the world today and in the future is essential to sustainable life on this planet.

Using the Middle School Environmental Literacy Survey, 6th grade students across Arkansas were surveyed to obtain a baseline measure of environmental literacy based on the four domains of environmental literacy included in the survey; ecological knowledge, environmental affect, cognitive skills, and behavior. Individual domain scores were combined into a composite environmental literacy score. Results were then compared to the …

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 …

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. …

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 …

Dropping Out In Southeast Kansas: Why Students Leave School Early, Garon Kent Wire

Graduate Theses and Dissertations

This qualitative study takes a deeper look into the lived experiences of students in southeast Kansas who have dropped out of high school. As a result, school and community leaders are better informed to create effective strategy, policy, and practice in dropout prevention.

Framed as a phenomenology, data was collected by conducting in-depth, face-to-face interviews with 12 participants and a focus-group interview with four participants. The researcher administered a survey/questionnaire to an additional 15 participants. Utilizing the Streamlined Codes-To-Theory Model (Saldana, 2009); organizational, structural, and elaborative coding techniques were implemented to reduce the data into categories, which led to the …

Sedimentary Provenance Of The Wedington Member, Fayetteville Shale, From Age Relations Of Detrital Zircons, William Tyson Cains

Graduate Theses and Dissertations

U-Pb geochronology of detrital zircons collected from the Chesterian Wedington Sandstone allows interpretation of sediment provenance and dispersal patterns in the southern midcontinent during the Late Mississippian. Detrital zircons analyzed from six samples of Wedington Sandstone yielded a final result of 565 concordant analyses used for interpretation. Results are plotted as Probability-Density Plots to interpret the spectrum of ages. Significant peaks occurred at 350-500 Ma, 950-1250 Ma, 1300-1500 Ma, 1600-1800 Ma, 1800-2300 Ma, and >2500 Ma. These peaks are interpreted as sourced by crystalline rocks within the Laurentian craton from Taconic-Acadian, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Superior Provinces. The …

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 …

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 …

An Experimental And Computational Evaluation Of The Importance Of Molecular Diffusion In Gas Gravity Currents, Jeremy Jac Herman

Graduate Theses and Dissertations

The accidental release of hazardous, denser-than-air gases during their transport or manufacture is a vital area of study for process safety researchers. This project examines the importance of molecular diffusion on the developing concentration field of a gas gravity current released into a calm environment. Questions which arose from the unexpectedly severe explosion in 2005 at Buncefield, England were of particular interest. The accidental overfilling of a large tank with gasoline on a completely calm morning led to a massive open air explosion. Forensic evidence showed that at the time of ignition, a vapor cloud, most of which now appears …

Attitudes And Behaviors In Online Communities: Empirical Studies Of The Effects Of Social, Community, And Individual Characteristics, Richard Kumi

Graduate Theses and Dissertations

Online communities and communities of practice bring people together to promote and support shared goals and exchange information. Personal interactions are important to many of these communities and one of the important outcomes of personal interactions in online communities and communities of practice is user-generated content. The three essays in the current study examines behavior motivation in online communities and communities of practice to understand how Social and personal psychological factors, and user-generated influence attitudes, intentions and behaviors in online communities.

The first essay addresses two research questions. First, how does Social capital influence exchange and combination behaviors in online …