Digital Commons Network^™

Evaluation Of Best Management Practices To Reduce Nutrients Runoff In Watersheds In Arkansas, Hector German Rodriguez Diaz

Graduate Theses and Dissertations

There are many non point sources (NPS) of pollution issues across the state of Arkansas. Each region of the state has different concerns. Many watersheds have been included in the Arkansas's 2008 303(d) list for NPS impairments with sediment and nutrients being the primary causes of concern. This research hypothesized that there are no cost or net returns risks when adopting best management practices (BMPs) to control nutrients runoff and that selection, timing, placement and cost have no impact on the implementation of BMPs. Using two priority watersheds, the L'Anguille River and the Lincoln Lake, as examples, the environmental benefits …

Thin Film Integrated Capacitors With Sputtered-Anodized Niobium Pentoxide Dielectric For Decoupling Applications, Susan Jacob

Graduate Theses and Dissertations

Electronics system miniaturization is a major driver for high-k materials. High-k materials in capacitors allow for high capacitance, enabling system miniaturization. Ta2O5 (k~24) has been the dominant high-k material in the electronic industry for decoupling capacitors, filter capacitors, etc. In order to facilitate further system miniaturization, this project has investigated thin film integrated capacitors with Nb2O5 dielectric. Nb2O5 has k~41 and is a potential candidate for replacing Ta2O5. But, the presence of suboxides (NbO2 and NbO) in the dielectric deteriorates the electrical properties (leakage current, thermal instability of capacitance, etc.). Also, the high oxygen solubility of niobium results in oxygen …

Applications Of Variable Number Tandem Repeat Genotyping In The Validation Of An Animal Medical Model And Gene Flow Studies In Threatened Populations Of Reptiles, Candace D. Smith

Graduate Theses and Dissertations

We used variable number tandem repeats (VNTR) to validate the chicken as a human medical model for Pulmonary Arterial Hypertension. We identified seven regions on four chromosomes and interrogated for VNTR markers that significantly associate with Pulmonary Hypertension Syndrome/ascites. In those regions, we identified 7 candidate genes; AGTR1, ACE, p38MAPK, SST, 5HT2B, NET1, and CALM3 for further analysis as significantly contributing QTL for ascites/PHS. We also used variable number tandem repeats to measure gene flow and gather evidence for multiple paternity in a population of Timber rattlesnakes, Crotalus horridus. We were able to verify 1 VNTR that can be used …

Characterization And Functional Regulation Of Bioactive Peptides In Avian Macrophages And Heterophils, Lakshmi Kannan

Graduate Theses and Dissertations

Oligopeptides and low molecular weight polypeptides play central roles as effectors and signal transducers acting as hormones, neurotransmitters, growth factors, toxins, and antimicrobial factors that are important for the survival of the organism. Owing to the ubiquitous involvement of peptides in many key regulatory processes, we have been interested to identify native peptides in different cells and tissues and understand their functions. To conduct our studies, we used avian macrophages and heterophils as models of specialized cells which constitute central components of innate immunity. These studies involved (a) qualitative identification and characterization of the peptides associated with high intensity mass …

The Role Of Multiple Ccaat-Binding Factors In Candida Albicans Gene Expression, Lashall Lynn Bates

Graduate Theses and Dissertations

The CCAAT-binding factor is a heterooligomeric transcription factor that is evolutionarily conserved in eukaryotes. In yeast, the DNA-binding component that interacts with the CCAAT consensus sequence in promoters consists of the subunits termed Hap2p, Hap3p and Hap5p. In yeast and fungi, a fourth subunit, Hap4p, is required for regulating gene expression. The goal of this research is to understand the function of the Candida albicans CCAAT-binding factor and how it relates to virulence and pathogenicity. C. albicans is a human opportunistic pathogen responsible for a variety of mucosal and systemic infections that result in significant morbidity and mortality, particularly in …

New Infrared Spectral Data For 27 Asteroids: An Investigation Of Meteorite-Asteroid Relationships By Using The Modified Gaussian Model, Katherine Marie Gietzen

Graduate Theses and Dissertations

Asteroids provide unique insights into the origin and early history of the solar system. Since asteroids are considered to be fairly pristine, studying them provides opportunities to learn more about the primordial solar system, its materials, processes and history. Since the discovery in 1801 of the first asteroid, Ceres, during the era when everyone was searching for the "missing planet", astronomers have been trying to understand what they are, where they came from, why they exist and what they can tell us about how our solar system formed and evolved.

Within the asteroid population are a number of sub-populations, the …

Morphology Of Ingaas Multilayer Nanostructure On Gaas High-Index Surfaces, Yanze Xie

Graduate Theses and Dissertations

This work aimed to explore nanostructure configuration by growing multiple layers of strained InGaAs on GaAs high index surface. The knowledge learned would help to achieve a comprehensive picture of strain-driven nanostructure evolution. Ordered arrays of InGaAs quantum dots were demonstrated on GaAs(311)B. The ordering patterns depended on the thickness of GaAs interlayer between InGaAs Quantum Dots (QDs). With an increased interfacial thickness, a transition from two dimensional (2D) lateral ordering to 1D dot chains was observed. InGaAs growth on GaAs(311)A and GaAs(331)A ended up with 1D quantum wires (QWRs). Straight InGaAs QWRs were uniformly distributed across the surfaces owing …

Talking Us Into War: Problem Definition By Presidents Lyndon B. Johnson And George W. Bush, Barbara Ellen May Warner

Graduate Theses and Dissertations

How presidents talk us into war merges the study of problem definition in public policy with the study of rhetoric in communications. Using both qualitative and quantitative methods, this research analyzes the key words used by two presidents, Lyndon B. Johnson and George W. Bush, to persuade us into escalating a war in Vietnam and engaging in a pre-emptive war in Iraq, respectively. The findings indicate that presidents repeat words that are patriotic, emotive, metaphorical, symbolic and religious, tapping into American themes of Manifest Destiny and even predicting dire outcomes if we do not accept their definitions of the dangers …

Factors Affecting Redox Magnetohydrodynamics For Flow In Small Volumes, Matthew D. Gerner

Graduate Theses and Dissertations

Lab-on-a-chip technologies offer the possibility of developing analytical devices that are low-cost, portable, disposable, fast, and operable by non-technical personnel. Such devices require automated methods to manipulate ultra-small volumes (picoliters) of samples and solution, including pumping, stirring, and positioning. Current methods for ultra-small volume microfluidics have limitations that restrict their use including high voltage requirements, disadvantageous flow profiles or rates, and relatively complicated fabrication due to mechanical parts. Redox magnetohydrodyanmics (RMHD) that utilizes permanent magnets for portability shows promise as a micropump with ease of switching flow direction, no moving parts, compatibility with both aqueous and non-aqueous solutions, low voltages …

Proton Irradiation Effects On Semiconductor Cdse/Zns Core/Shell Nanocrystals, Stephen Graham Charter

Graduate Theses and Dissertations

The absorbance and photoluminescence measurement of semiconductor CdSe/ZnS core shell nanocrystals were reviewed and investigated after they were exposed to proton irradiation. The CdSe/ZnS core shell nanocrystals of 3.2nm and 4.4nm were commercially purchased and investigated. These nanocrystals were embedded in UV resin. Proton irradiation of energy 2MeV was applied at doses from 3 x 1013 protons cm-2 to 1.47 x 1015 protons cm-2 for both nanocrystal sizes. Absorbance measurements were conducted at 300K. Results from absorbance measurements showed slight broadening of the first exciton peak of both samples but was most noticeable in the 3.2nm nanocrystal sample. UV resin …

A Study Of The School Principal Labor Market In Arkansas: Implications For Incentive-Based Compensation Policies To Improve Principal Quality, Marc Jacob Holley

Graduate Theses and Dissertations

Improving principal quality in Arkansas may be a partial solution to the public policy problem of low performing public schools. Just as policymakers in other states are beginning to explore incentive-based compensation policies to improve principal quality, education policymakers in Arkansas should look to these policies as a way to align goals and minimize agency costs. Setting incentives tied to transparent, publicly available performance measures can resolve monitoring difficulties inherent in principal-agent relationships and can improve goal congruence by signaling clearly about policy priorities. Before plowing forward with performance pay reforms for school principals, Arkansas policymakers could make better decisions …

Understanding The Role Of Histones During Chromosome Segregation: A Study Of The Effects Of Histone Gene Dosage In Saccharomyces Cerevisiae, Rebecca Leigh Danforth

Graduate Theses and Dissertations

Chromatin plays a role in all cellular functions that involve DNA. These include, but are not limited to replication, recombination, transcription, and chromosome segregation. Chromosome segregation is an extremely well conserved cellular process and is essential for maintaining the genetic integrity of a cell. There is very strong evidence indicating that chromatin structure is critical for maintaining the fidelity of chromosome transmission, but its specific role(s) in this process remains unclear. Chromatin is comprised of arrays of nucleosomes that serve to compact DNA. These nucleosomes consist of 146 bp of DNA that is wrapped around a histone octamer; two each …

Droplet Assisted Self-Assembly Of Semiconductor Nanostructures, Kimberly Annosha Sablon

Graduate Theses and Dissertations

There is increasing interest in quantum dot (QD) structures for a plethora of applications, including optoelectronic devices, quantum computing and energy harvesting. While strain driven surface diffusion via stranski-krastanow (SK) method has been commonly used to fabricate these structures, a more recent technique, droplet epitaxy (DE) does not require mismatch strain and is therefore much more flexible in the combination of materials utilized for the formation of QDs.

As reported in this work, a hybrid approach that combines DE and SK techniques for realizing lateral ordering of QDs was explored. First, the droplet formation of various materials was discussed and …

Preparation, Separation, Purification, Characterization And Human Cell Line Anti-Cancer Evaluation Of Rice Bran Peptides, Arvind Kannan

Graduate Theses and Dissertations

Bioactive compounds are revolutionizing the nutritional and medicinal world with their inherent disease-fighting properties. A wide range of functional groups fall under the category of imparting health benefits. Compounds from both animal and plant origins have been generated as bioactive agents that have opened up new vistas for alternative medicine and natural healing. For example, in a debilitating disease like cancer, these compounds can act to suppress or delay the underlying pathology over and above the conventional treatment strategies involving drugs or chemotherapy. In other words conventional and invasive therapy, although still considered appropriate at certain stages of cancer, their …

Evaluating The Policies That Lead To Substantial Tuition Variation At Public Land-Grant Universities, Brent Alexander Burgess

Graduate Theses and Dissertations

Since the 1980's, the tuition at public colleges and universities has increased at a rate far beyond that of normal inflation. During this period, many public institutions have increased their tuitions exponentially, while others have chosen or been able to retain stable and relatively inexpensive tuition rates. The aim of this study was to examine what policies and external trends are responsible for public institutions having such wide variation in their tuition costs. Therefore, this study isolated one type of public institution, which was land-grant universities, that have a mission and tradition of providing affordable educations to examine the causes …

The Membrane Interface Of Chloroplast Signal Recognition Particle-Dependent Protein Targeting, Naomi Jane Marty

Graduate Theses and Dissertations

A novel signal recognition particle (SRP) found in the chloroplast (cpSRP) works in combination with the cpSRP receptor, cpFtsY, to facilitate the post-translational targeting of a family of nuclear-encoded thylakoid proteins to the Alb3 translocase in thylakoid membranes. Work here focused on understanding events at the membrane that take place to ensure targeting of the cpSRP-dependent substrate to Alb3. Specifically, we sought to understand the structural and functional role of membrane binding by cpFtsY, a protein that exhibits the ability to partition between the membrane (thylakoid) and soluble (stroma) phase during protein targeting. We also sought to understand whether a …

Coping With Dr-Cafta: Assessing The Impact Of The Agreement And Designing Adjustment Programs For Sensitive Agriculture In Honduras, Alvaro Durand-Morat

Graduate Theses and Dissertations

Honduras has for almost two decades embraced economic integration as a way to achieve sustained economic growth. The DR-CAFTA agreement signed in 2004 represents another step towards economic openness. The agreement generated a heated debate about the benefits and costs to the Honduran economy. Previous assessments suggest that Honduras will have a marginal aggregate benefit from DR-CAFTA. The findings from this study suggest that the agreement might actually yield a marginal loss vis-à-vis the counterfactual. Previous studies also stress the potential for large losses resulting from the agreement, particularly for some traditional and sensitive agricultural sectors. The findings from this …

Imaging Second-Harmonic Radiation And Scattering Patterns In Zno Micro/Nanostructures, Katrina Marie Geren

Graduate Theses and Dissertations

The optical characteristics of ZnO nanostructures have recently garnered interest due to the inclusion of these structures in many nanoscale optical and optoelectronic devices. This thesis will address several characteristics involving second harmonic generation and scattering in ZnO nano- and microstructures. A method will be presented for determining the nonlinear coefficients of the second order susceptibility in a single ZnO rod. This method uses transmission geometry where previous methods have employed back-reflected irradiation. The nonlinear coefficients found using this new technique were consistent with previous data from similar structures. Models will be presented for predicting the second harmonic scattering patterns …

Modeling Of Compositionally Graded Barium Strontium Titanate From First Principles, Laura Elizabeth Walizer

Graduate Theses and Dissertations

"Barium Strontium Titanate (BaxSr1-xTiO3 or BST) is a Perovskite alloy of interest for both technological and intellectual reasons. Its ferroelectric and piezoelectric properties make it useful in a variety of electric components such as transducers and actuators, and BST in particular is a material of interest for the development of a ferroelectric RAM for computers. The inclusion of SrTiO3, an incipient ferroelectric, and the fact that the properties of a BST system depend strongly on its relative composition of BaTiO3 and SrTiO3 (ST), make also this a material of high interest. Compositionally graded systems are of further interest , partly …

Gender Differences In Psychopathy, Jamie Lynn See

Graduate Theses and Dissertations

No abstract provided.

Multi-Mode Coherent Ladar Imaging Via Diverse Periodic Pseudo Noise Waveforms And Code Division Multiple Access Apertures, Matthew Paul Dierking

Graduate Theses and Dissertations

No abstract provided.

Auditory Picture Superiority Unconfirmed In Recognition Memory, Brian Allen Taylor

Graduate Theses and Dissertations

No abstract provided.

Globalization And Militant Hindu Nationalism: The New Context For Theology In India, Satish Antony Joseph

Graduate Theses and Dissertations

No abstract provided.

Synthesis And Cure Mechanism Characterization Of Phenylethynyl-Terminated Imide Oligomers, Susanna Branion Back

Graduate Theses and Dissertations

No abstract provided.

A Finite Element Study Of Sliding Friction Between Rough Surfaces, Chad Andrew Burton

Graduate Theses and Dissertations

No abstract provided.

Do Family And Personality Variables Moderate The Effects Of Thin-Ideal Media On Body Image?, Nicole Renee Bosse

Graduate Theses and Dissertations

No abstract provided.

The Effects Of A Class-Wide Group Contingency To Increase Tootling, Amy Lynn Agosta

Graduate Theses and Dissertations

No abstract provided.

Teaching Composition: Reaching Non-Native Students Within The English Composition Classroom, Christine Dianne Maddox

Graduate Theses and Dissertations

No abstract provided.

The Effectiveness Of The Phonics Dance On Reading Fluency, Mark Wayne Boertje

Graduate Theses and Dissertations

No abstract provided.

Blackout, Christopher J. Burnside

Graduate Theses and Dissertations

No abstract provided.