Digital Commons Network^™

Improvements In Microdialysis Sampling Extraction Efficiency Using Recycled Flow, Justin Cole Deaton

Graduate Theses and Dissertations

Incomplete recovery during microdialysis sampling is hindering important research in neurology, proteomics, and immunology. Although the current generalized solution, decreasing volumetric flow rates (Q), has been and will remain to be a useful strategy it has reached it's a physical limitation due to evaporation at the collection site. Consequently, many important signaling molecules, such as signaling proteins, remain difficult to study. It is more fundamental to consider relative recovery as a function of the interaction time between the perfusate and the environment surrounding the probe.

In this work an increase in relative recovery was predicted by a mathematical model. Using …

"The Adding Machine": A Director's Notebook, Esteban Arévalo Ibáñez

Graduate Theses and Dissertations

The following thesis is a compilation and analysis of my experiences during the process of directing The Adding Machine by Elmer Rice, from its conception in the director's imagination, to the collaboration with the design team and the actors. It begins with research and the director's approach to the play. Then a description of the process follows, starting with the design meetings and auditions, and going through rehearsals, performances, and evaluations of the show by faculty and peers. This description is accompanied by a journal that contains the director's thoughts and reactions to discoveries and challenges that came up during …

Characterization And Epidemiology Of Soybean Vein Necrosis Associated Virus, Jing Zhou

Graduate Theses and Dissertations

Soybean vein necrosis disease (SVND) is widespread in major soybean-producing areas in the U.S. The typical disease symptoms exhibit as vein clearing along the main vein, which turn into chlorosis or necrosis as season progresses. Double-stranded RNA isolation and shot gun cloning of symptomatic tissues revealed the presence of a new tospovirus, provisionally named as Soybean vein necrosis associated virus (SVNaV). The presence of the virus has been confirmed in 12 states: Arkansas, Illinois, Missouri, Kansas, Tennessee, Kentucky, Mississippi, Maryland, Delaware, Virginia and New York. Symptomatic samples collected from eight states (AR, IL, MO, MS, KS, TN, MD and DE), …

False Smut Of Rice: Histological Analysis Of Infection, Liem Thi Thanh Nguyen

Graduate Theses and Dissertations

False smut of rice, caused by Ustilaginoidea virens (Cooke) Takahashi (Teleomorph: Villosiclava virens), has become a common disease in most major rice growing regions throughout the world. Considerable confusion exists regarding the infection process and the disease cycle. Therefore, a clearer understanding of pathogenesis caused by Ustilaginoidea virens is critical for future efforts to develop genetic and chemical tools to manage false smut in Arkansas and other regions of the world. The overall goal of this research was to clarify the infection process underlying false smut, with emphasis on comparing and contrasting the histological basis of root and foliar infections. …

Effect Of Body Size And Exercise On Mood State, Alexandra Lachance

Graduate Theses and Dissertations

Exercising in the presence of nature (i.e., "green exercise"), has been shown to heighten the physiological and mental benefits of traditional exercise on non-obese individuals. The effects of green exercise on obese individuals are unknown. It is hypothesized that green exercise is more beneficial for obese (greater positive improvements in mental health scores), compared to non-obese individuals. For example, the benefits of green exercise could help lower feelings of depression, improve mood and self-esteem to increase the propensity of obese individuals to meet exercise recommendations. Accordingly, this study investigated the physiological and psychological effects of green exercise on 12 obese …

Energy And Spectral Efficient Wireless Communications, Guoqing Zhou

Graduate Theses and Dissertations

Energy and spectrum are two precious commodities for wireless communications. How to improve the energy and spectrum efficiency has become two critical issues for the designs of wireless communication systems. This dissertation is devoted to the development of energy and spectral efficient wireless communications. The developed techniques can be applied to a wide range of wireless communication systems, such as wireless sensor network (WSN) designed for structure health monitoring (SHM), medium access control (MAC) for multi-user systems, and cooperative spectrum sensing in cognitive radio systems.

First, to improve the energy efficiency in SHM WSN, a new ultra low power (ULP) …

Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller

Graduate Theses and Dissertations

Sirex (Hymenoptera: Siricidae) woodwasps develop within xylem of host conifers. Sirex females drill through the bark, phloem and into xylem tissues where they deposit eggs along with a symbiotic Amylostereum fungus. The presence of Amylostereum is necessary for successful development of Sirex immatures as the larvae are unable to derive adequate nutrition from xylem in the absence of the fungus. The Eurasian woodwasp, Sirex noctilio F., was discovered in northeastern North America in 2004. Sirex noctilio has caused significant economic damage in Pinus radiata D. Don plantations of the southern hemisphere, but is of little economic significance in its native …

Design And Analysis Of An Adaptive Asynchronous System Architecture For Energy Efficiency, Brent Michael Hollosi

Graduate Theses and Dissertations

Power has become a critical design parameter for digital CMOS integrated circuits. With performance still garnering much concern, a central idea has emerged: minimizing power consumption while maintaining performance. The use of dynamic voltage scaling (DVS) with parallelism has shown to be an effective way of saving power while maintaining performance. However, the potency of DVS and parallelism in traditional, clocked synchronous systems is limited because of the strict timing requirements such systems must comply with. Delay-insensitive (DI) asynchronous systems have the potential to benefit more from these techniques due to their flexible timing requirements and high modularity. This dissertation …

Female Academic Department Chairs At A Public, Very High Research Activity University: Exploring Their Career Pathways To Success, Tamara Marcelle St.Marthe

Graduate Theses and Dissertations

The advancement of women into academic leadership remains a problem facing public, high-research activity universities. While there are more women who are qualified to assume the position of department chair in research institutions today than there were 30 years ago, women still lag behind their male counterparts in holding these academic leadership roles. The purpose of this study was to examine the personal and professional career experiences of women department chairs in a public, very high research activity institution, and to provide advice to women faculty seeking to become a department chair in the future. The department chair is among …

The Lived Experience Of The Parents Of High School Dropouts: A Phenomenological Study, Christine Ann Silano

Graduate Theses and Dissertations

The purpose of this study is to describe the experiences and perceptions of parents whose children did not receive a high school diploma. This subpopulation has been rarely studied. The central question is, "What are the perceptions and experiences of the parents of public high school dropouts as they pertain to schools, their children, and themselves?"

This phenomenological study examined the lived experience of the parents of high school dropouts. Five women and one man participated in the study by sitting for interviews. The collected interview data was transcribed and analyzed using qualitative methodology including open and axial coding as …

Documentation And Control Of Acetolactate Synthase-Resistant Barnyardgrass (Echinochloa Crus-Galli) In Arkansas Rice, Michael Joshua Wilson

Graduate Theses and Dissertations

Barnyardgrass, the most problematic grass weed of Arkansas rice, was found resistant to propanil in 1990, and since then, it has evolved resistance to quinclorac and clomazone. Barnyardgrass is now believed to have evolved resistance to acetolactate synthase (ALS)-inhibiting herbicides. The goal of this research was to confirm and determine the level of resistance of the putative resistant biotype to the ALS-inhibiting herbicides imazethapyr, bispyribac, and penoxsulam and to develop herbicide programs for controlling ALS-, propanil-, quinclorac-, and clomazone-resistant barnyardgrass. The lethal dose needed to kill 50% of the putative ALS-resistant plants was higher than that of the susceptible biotype …

Preparedness To Implement Wellness Strategies: Perceptions Of School Counselors, Tena Burnett

Graduate Theses and Dissertations

The purpose of this study is to survey school counselors to determine their knowledge and perceived preparedness to implement wellness strategies in school counseling programs. Wellness plans are a requirement for thousands of public school districts in the United States. There are no established standards for the training of school counselors in the area of wellness. School counselors are in a unique position to positively impact students through the use of wellness programs and strategies. School counselors from a mid-south state (N = 156) completed an electronic survey to measure how they implement wellness strategies and their perceived preparedness in …

Essays In Development Economics And Economics Of The Family, Aaron Johnson

Graduate Theses and Dissertations

Chapter 1 explores a potential solution to the continuing disequlibrium in microfinance markets. I design a mechanism to aid in securitization of microloans, using a dynamic investment pool governed by a Central Microcredit Clearinghouse (CMC), that would sell investment units back to MFIs and outside investors simultaneously. The CMC would serve as a catalyst to this other avenue of microcredit financing, securitization of microloans, which could help spawn the type of growth in investor-based funding of MFIs that is so urgently needed. Chapter 2 analyzes Official Development Assistance (ODA) commitment and disbursement activity in terms of motivation, considering that the …

Trait Differences In Gender In Technology Use And Study Habits Of Rural Community College Students, Phillip Marc Wilson

Graduate Theses and Dissertations

The purpose for conducting the study was to explore the trait differences by gender of the study habits and technology use patterns of rural community college students. Significant research and data presently exists at the university level specific to study habits and technology use, but little research had been conducted targeting those topics in a rural community college setting.

The following questions guided the research:

1. What were the study habits of rural community college students?

2. How did rural community college students use technology?

3. Were there significant differences, by gender, in the study habits of rural community college …

Witch Hazel Advent, The Story Of An Ozark Poet, Sarah Moore Chyrchel

Graduate Theses and Dissertations

The goal of this Master's thesis project was to document the life of my maternal step-grandfather, John Ross Rule, in a visually compelling manner. Using equipment provided by the Lemke Department of Journalism at the University of Arkansas, I shot and edited a half hour long documentary film comprised of interviews and footage of John at his home near Winslow, Arkansas. John is a talented poet, and segments of his poetry are woven throughout the film.

The inspiration for this project is deeply rooted in place: the remote farmstead in the Boston Mountains of northwestern Arkansas that my grandparents called …

Predictability Of Food And Wine Pairing Using A Sensory Approach, Rebeckah L. Koone

Graduate Theses and Dissertations

The purpose of this study was to explore significant differences in perception of match for a variety of food and wine styles; evaluate the impacts of wine sweetness level, wine acidity level, and wine tannin level on perception of match; and to investigate the impact of food and wine expertise on perceived level of match. A field research design was used to explore expert recommendations of food and wine combinations to obtain broader feedback on consumer perceptions. The population consisted of a convenience sample of 248 students enrolled in a continuing education course in food and wine pairing at George …

Investigating The Sensitivity Of Goodness-Of-Fit Indices To Detect Measurement Invariance In The Bifactor Model, Jam Khojasteh

Graduate Theses and Dissertations

A Monte Carlo simulation study was conducted to evaluate the sensitivities of five commonly used goodness-of-fit indices to detect metric invariance properties of the bifactor model. The fit indices that performed the best in terms of power were Gamma and Mc. In addition, Gamma, Mc, CFI, and RMSEA all held Type I error to a minimum. However, only Gamma and CFI are recommended to use in the bifactor model because the other GOF indices have cutoff values that are too large. For Gamma and CFI values of -.026 to -.045 and -.004 to -.009, respectively indicate a lack of metric …

Master Principals' Perceptions Of The Impact Of The Arkansas Leadership Academy's Master Principal Program On Leadership Practices, School Cultures And Student Achievement, Diana Peer

Graduate Theses and Dissertations

A qualitative dissertation study was conducted to examine the impact of the Arkansas Leadership Academy's Master Principal Program through the perspective of those who have completed the entire program and attained designation as a Master Principal. A logic model for the Master Principal Program offered a context for the study. A review of relevant literature provided the identification of gaps in the research which included limited findings for a program comparable to the Master Principal Program. Research methods for this phenomenological study were explained. The research sample included Master Principals, as of 2011. Interviews and a focus group using collaborative …

Topics On Light-Emitting-Diode Driver Research, Jaber Hasan

Graduate Theses and Dissertations

In this dissertation, light-emitting-diode (LED) drivers are investigated for efficiency issues related to driving Red-Green-Blue (RGB) pixels and multiple LED strings in parallel. A high-efficiency digitally controlled RGB LED driver was designed for driving a 3x3 RGB LED display panel. A multiplexer was used to sense the voltage drop across the current controllers. This driver maintained a minimum drive voltage across the RGB LED pixels required to keep it in regulation leading to a reduction of unwanted power losses in the RGB LED pixels by selecting the minimum drop across the current-controllers as the reference voltage of the digital controller. …

The Academic Effects Of Learning Styles On Esl (English As A Second Language) Students In Intensive English Language Centers, Baderaddin Mahmood Yassin

Graduate Theses and Dissertations

This study investigated the learning styles of ESL students (students who learn English as a second language). The focus in this study was on the ESL Arab Gulf (Saudi Arabia, Oman, Kuwait, and United Arab Emirates) students who study English as a second language in Intensive English Language Centers (IELCs) in the United States. The study explored the ESL Arab Gulf students' learning style preference and how they are affected by different variables such as cultural background, gender, and language level in IELCs. ESL Arab Gulf students were administered the VARK Learning Styles questionnaire. It measures several sensory types of …

Taxonomy And Dna Barcoding In The Genus Manfreda (Salisb.) Asparagaceae, William David Ritchie

Graduate Theses and Dissertations

The genus Manfreda Salisb. of Asparagaceae is a genus of potential horticultural interest and is currently subject to breeding efforts at the University of Arkansas. A lack of taxonomic clarity however undermines the classification of potential inter - and intrageneric hybrids. The study aims to assess existing species delimitation within the genus Manfreda employing morphology while investigating the potential utility of Consortium for the Barcode of Life Plant (CBOL) DNA Barcodes for identification of specific taxa and an External Transcribed Spacer (ETS) - Internal Transcribed Spacer (ITS) DNA barcode for developed hybridized taxa.

Observation of 855 herbarium specimens facilitated phylogenetic …

Aesthetic Qualities Of Websites And Their Effects On Public Perceptions Of Agricultural Issues And Organizations, Chase Tyler Hundley

Graduate Theses and Dissertations

This study sought to evaluate perceptions of agricultural issues and organizations based on how information is presented visually in websites. Researchers intended the results to be used to help the agricultural industry more effectively communicate information through better website design and increased persuasiveness. The study was conducted through the use of three focus group sessions as mapped out by Krueger (1998a, 1998b, 1998c) and Morgan (1998a, 1998b). The study used non-agriculture students purposively selected from a class in the University of Arkansas School of Human Environmental Sciences as participants in the study. The subject demographics closely resembled the primary demographics …

An Ethnographic Case Study Of A Deaf Workforce Collective, Peter Shane Butler

Graduate Theses and Dissertations

This ethnographic study seeks to increase our understanding of the individual and shared experiences of five members of a Deaf United States Postal Service (USPS) collective employment cohort in regards to their early learning experiences, how these experiences led to collective employment, and how the collective employment opportunity led them to establish a new Strong Deaf Community in Houston. The data collected through semi structured interviews will be used to increase our understanding about how Strong Deaf Communities form, and what purpose they serve for grassroots members.

This study also seeks to shed light on why it is critical for …

Pre- And Post- Wage Differences Of Trade Adjustment Assistance Job Training Participants In Arkansas, Kimberley Hall Gordon

Graduate Theses and Dissertations

A number of costs are associated with the implementation of trade agreements not the least of which is the cost to the American workforce. The information age ushered in an era of globalization unlike anything the world economy had experienced before. As countries raced forward to dominate emerging markets and grow market share, millions of American workers were left in the wake. A remedy to the plight of the dislocated worker was found in trade adjustment assistance, specifically in job training benefits.

This study examined the wage differences experienced by Trade Adjustment Assistance (TAA) job training participants served through the …

Ideology In Popular Late Twentieth And Twenty-First Century Children's And Young Adult Literature And Film, Iris Grace Shepard

Graduate Theses and Dissertations

Texts created for the consumption of children and young adults are not simple texts made for the sole purpose of entertaining young audiences. In fact, these texts are complicated, multi-faceted texts that function both in the creation and performance of childhood. Children's and young adult literature and film disseminated mainstream ideology about young people's place in society and attempt to enculturate young readers and viewers in regards to race, gender, age, and Social class. However, by helping young people interact critically with these texts, critical thinking skills as well as a passion for reading can be fostered. In addition, by …

Effects Of Obesity On Thermoregulation And Cardiovascular Function During Exercise In Females, Jon David Adams

Graduate Theses and Dissertations

Previous research has shown that obese individuals are at greater risk for heat illnesses because of impaired thermoregulation. However, laboratory studies investigating cardiovascular and thermoregulatory function in obese individuals are difficult to interpret because of low sample sizes and methodological concerns. The purpose of this study was to determine if there are differences in thermoregulatory and cardiovascular function between obese and non-obese females. Twenty-four females, 13 obese (43.3 ± 4 .3 % fat, 77.2 ± 13.7 kg) and 11 non-obese (27.8 ± 6.0 % fat, 55.7±6.7 kg), cycled for 60 min in a warm environment (~40°C, 30% humidity) at a …

Do Honors Programs Make A Difference During The First Year Of College? The Development Of Critical Thinking Skills And Exposure To Good Practices In Undergraduate Education, Amanda Kay Moore

Graduate Theses and Dissertations

This longitudinal study analyzed pretest-posttest data to 1) examine the influence of honors programs on first-year college students' critical thinking skills, 2) to determine whether students in honors programs receive more exposure to good practices in undergraduate education than their non-honors peers, and 3) to assess the effect of good practices on critical thinking. The quasi-experimental study also investigated whether the influence of honors programs on critical thinking skills varied in direction and magnitude for male versus female students and White versus students of color. To replicate an earlier study conducted by Seifert et al. (2007), the current study utilized …

Perceptions Of A Middle School Reconfiguration: A Descriptive Case Study, Karen Billingsley Lasker

Graduate Theses and Dissertations

The purpose of this qualitative research study was to follow 1 principal's journey to assist the district in its reconfiguration goals, and help the school change through deep examination of district personnel's and parents' perceptions of the change process. This was done by acknowledging distinctions and differences between junior high schools, the current middle school, and the new middle school, delineated by current middle school-reform research. This study explored issues regarding the policies, personnel, decision-making strategies, timelines, and organizational structures of the new middle school.

The reconfiguration resulted in rezoning attendance zones, reconstructing the new high school, raising the new …

Predictors Of Academic Success For The National Board Dental Hygiene Examination And The Southern Regional Testing Agency Clinical Exam, Melissa Gail Efurd

Graduate Theses and Dissertations

The purpose for conducting this study was to investigate and describe the relationship between applicant criteria for a dental hygiene program and subsequent outcomes on credentialing exams: the National Board Dental Hygiene Exam and the Southern Regional Testing Agency clinical exam. Because admission criteria play a crucial role in applicant selection, choosing students, that will successfully complete the program as well as the necessary credentialing exams, is a particularly crucial task for admission committees. The study had three elements. First, it investigated the relationship between the variables of age, undergraduate GPA and scores from the Psychological Services Bureau Health Occupations …

The Relationship Of Peer Acceptance, Age, Gender, Ethnicity, And Appearance Among Preschoolers, Kora Klaire Stuffelbeam

Graduate Theses and Dissertations

The purpose of this study was to examine preschool children's acceptance of peers. The term peer acceptance is defined as "the degree a child is Socially accepted or rejected by his or her peer group." Johnson et al. (2002) found children between the ages of three and five were able to develop friendships and Social skills that would impact their acceptance among peers. The study determined if children based their choice of peers according to a child's age, gender, ethnicity, appearance, and/or Social skills. The subjects of this study were 31 children whose ages were three-, four-, and five-years-old who …