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Investigation Of The Structure-Activity Relationship Of Pseudo-Single-Crystal Platinum Electrodes By Scanning Electrochemical Microscopy, Yulin Wang Dec 2013

Investigation Of The Structure-Activity Relationship Of Pseudo-Single-Crystal Platinum Electrodes By Scanning Electrochemical Microscopy, Yulin Wang

Theses and Dissertations

The study of the structure-activity relationship of electrode surfaces is fundamentally important in electrocatalysis research. Yet, the methods and techniques used for the examination of structure-activity relationship so far are limited by their capabilities, and the exploration of electrochemistry at complex surfaces is very challenging. In this study, the correlation between the electrode surface structure and its corresponding activity in two electrochemical reactions were investigated: an electrochemical etching reaction and an electrocatalysis reaction. A polycrystalline Pt electrode was galvanically etched to expose the underlying well-defined crystallites serving as pseudo-single-crystal electrodes. Atomic force microscopy (AFM) complemented with electron backscatter diffraction (EBSD) …


Molecular Basis Of Salmonella Enterica Serovar Kentucky Attachment To Broiler Skin, Sanaz Salehi Dec 2013

Molecular Basis Of Salmonella Enterica Serovar Kentucky Attachment To Broiler Skin, Sanaz Salehi

Theses and Dissertations

The presence of Salmonella enterica throughout the production and processing continuum is a concern in broiler industry. While federal regulations have lowered the acceptable level of Salmonella contamination on broiler carcasses, the mechanisms that contribute to pathogen attachment are not fully understood. Salmonella Kentucky has become the predominant Salmonella serovar isolated from broilers carcasses at the end of the immersion chill tank. In Europe and Africa this serovar has been shown to acquire antibiotic resistance genes that may lead this non-typhoidal serotype to become a potential public health concern. To investigate the genes that are involved in colonization of the …


Monitoring Gulf Coast Fish Quality, Karl Edward Bell Dec 2013

Monitoring Gulf Coast Fish Quality, Karl Edward Bell

Theses and Dissertations

Globalization and the rise of fish importation has led to an increase in mislabeling. To combat this problem, analytical and molecular methods have been employed. First, nitrofuran metabolites were extracted, hydrolyzed, and derivatized in channel catfish, swai, and tilapia. Utilizing high performance liquid chromatography coupled with triple quadrupole mass spectrometry, derivatized metabolites were detected at levels of 1 ng/mL with coefficients of determination greater than 0.998. Recoveries greater than 90% and relative standard deviation less than 17% indicate that the method is successful. Secondly, chip based electrophoresis coupled with restriction fragment length polymorphism was used for the species differentiation. By …


Formation Of Oxidative-Stress Resistant Phenotypes Of Listeria Monocytogenes Serotypes 1/2a And 4b And Their Stability At 37oc And 4oc, Piumi De Abrew Abeysundara Dec 2013

Formation Of Oxidative-Stress Resistant Phenotypes Of Listeria Monocytogenes Serotypes 1/2a And 4b And Their Stability At 37oc And 4oc, Piumi De Abrew Abeysundara

Theses and Dissertations

The purpose of this study was to induce an oxidative-stress adaptation in Listeria monocytogenes Bug600 (serotype 1/2a) and F1057 (serotype 4b) by pre-exposing to sublethal H2O2 and alkali-stress either singly or sequentially. Our findings show that the sequential pre-exposure of cells to pH 9 for 30 min treatment followed by 50 ppm H2O2 for 30 min at 37°C yielded the highest oxidative-stress resistant phenotypes of L. monocytogenes Bug600 and F1057. The sublethal H2O2 and sublethal alkali-stress induced oxidative-stress adaptations were completely reversible within 60 min at 37°C in the absence of such sublethal stress. However, the oxidative-stress adaptation induced at …


Gender Characteristics And Barriers To Community College Leadership, Joanna Mcclellan Dec 2013

Gender Characteristics And Barriers To Community College Leadership, Joanna Mcclellan

Theses and Dissertations

Prior research has determined that there are still gender barriers that women must overcome to reach administrative positions in many employment settings. Gender barriers to leadership positions have been and continue to be a sensitive matter that must be addressed by community college administrators. This exploratory quantitative research study examined rural community college administrators’ perceptions about gender barriers and explored administrators’ perceptions about management styles based on gender. The study population included 596 community college administrators in the United States. Of those, 128 community college administrators chose to participate in this study and completed a 42-item researcher designed survey instrument …


Evaluation Of Quantitative Polymerase Reaction And Microbial Volatile Organic Compounds To Determine Resistance To Aspergillus Flavus In Maize, Alicia Kay Wood-Jones Dec 2013

Evaluation Of Quantitative Polymerase Reaction And Microbial Volatile Organic Compounds To Determine Resistance To Aspergillus Flavus In Maize, Alicia Kay Wood-Jones

Theses and Dissertations

Screening for resistance to Aspergillus flavus and aflatoxin contamination in maize is an ongoing effort by universities, state and federal agencies. We evaluated two techniques to screen for resistance; quantitative polymerase reaction (QPCR) and solid-phase microextraction (SPME). Methods were adapted to accurately detect and quantify the fungus in culture and in the vegetative stage of plant tissues. These assays can eliminate microbiological techniques. The primary objectives of the study were to utilize 1) QPCR to detect and quantify fungal biomass in maize stem tissues to evaluate resistance in maize genotypes to A. flavus colonization in situ and in vivo and …


Examining The Influence Of Nutritional Behaviors, Knowledge And Attitudes On Body Mass Index Of Adults In North Mississippi, Gloria Therese Broughan Dec 2013

Examining The Influence Of Nutritional Behaviors, Knowledge And Attitudes On Body Mass Index Of Adults In North Mississippi, Gloria Therese Broughan

Theses and Dissertations

Individuals with weight statuses approaching obesity may be at risk for chronic health problems. Diet, weight, health behaviors, level of knowledge, and attitudes or perceptions have been identified as key factors influencing body weight. The purpose of this study was to determine which factors were related to BMI in adults in north Mississippi and to determine if there were relationships between those factors. A telephone survey was conducted with 500 participants (mean age 46.3 ± 18.5). The average BMI was 27.5 ± 6.2 kg/m2. Knowledge and attitude/perception-based data were associated with a higher BMI in the population more than dietary …


Adult Learning And Development Theories And Principles Represented In Theater, Jeffrey Miele Dec 2013

Adult Learning And Development Theories And Principles Represented In Theater, Jeffrey Miele

Theses and Dissertations

The purpose of this study was to investigate how adult learning and development theories and principles are represented in theater. The study also investigated if there was significant evidence to support the idea of using dramatic works as an example to illustrate adult learning and development theories and principles as an educational tool. Ten plays were analyzed along with an accompanying rubric that the evaluator completed while reading the plays. The rubric searched for information if adults and/or educators were present in the text, how andragogy and barriers were presented, along with other theories and principles. The findings suggested that …


Certain Agave Species Exhibit The Capability To Be Moderately Productive Under Conditions Of High Salt And Drought Stress, Steven J. Bergsten Dec 2013

Certain Agave Species Exhibit The Capability To Be Moderately Productive Under Conditions Of High Salt And Drought Stress, Steven J. Bergsten

Theses and Dissertations

Water availability and arable lands are increasingly limiting resources in many parts of the U.S., particularly in semi-arid and arid regions. As a means of addressing food and fuel demands associated with burgeoning population growth, highly productive and water-use efficient crops need to be identified. One potential crop, Agave, merits consideration and evaluation due to its putative capability to provide sustenance and energy despite growing in water-limited regions and on marginal soils. However, little is known regarding the productivity these succulent plants will have under growing conditions of the Southwest, where high concentrated saline soils are abundant, and water is …


Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell Dec 2013

Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell

Theses and Dissertations

The purpose of this work was to analyze the biomechanics of degeneration, damage, and failure in biological soft tissues both experimentally and computationally to provide insight into tendon or ligament tearing, tendo-achilles lengthening and lumbar spine dysfunction. For soft tissue tearing, experimental studies for calculating fracture toughness were performed and determined that tendons and ligaments are able to completely resist tear propagation. For tendo-achilles lengthening, a damage model was developed to mimic the behavior of the lengthening that occurs as a result of the percutaneous triple hemisection technique. The model provided insight for predicting the amount of lengthening that occurs …


Molecular Modeling Of Dna For A Mechanistic Understanding Of Hybridization, Terry Jacob Schmitt Dec 2013

Molecular Modeling Of Dna For A Mechanistic Understanding Of Hybridization, Terry Jacob Schmitt

Theses and Dissertations

DNA microarrays are a potentially disruptive technology in the medical field, but their use in such settings is limited by poor reliability. Microarrays work on the principle of hybridization and can only be as reliable as this process is robust, yet little is known at the molecular level about how the surface affects the hybridization process. This work uses advanced molecular simulation techniques and an experimentally-parameterized coarse-grain model to determine the mechanism by which hybridization occurs on surfaces and to identify key factors that influence the accuracy of DNA microarrays. Comparing behavior in the bulk and on the surface showed, …


Identification Of The Binding Partners For Hspb2 And Cryab Reveals Myofibril And Mitochondrial Protein Interactions And Non-Redundant Roles For Small Heat Shock Proteins, Kelsey Murphey Langston Dec 2013

Identification Of The Binding Partners For Hspb2 And Cryab Reveals Myofibril And Mitochondrial Protein Interactions And Non-Redundant Roles For Small Heat Shock Proteins, Kelsey Murphey Langston

Theses and Dissertations

Small Heat Shock Proteins (sHSP) are molecular chaperones that play protective roles in cell survival and have been shown to possess chaperone activity. As such, mutations in this family of proteins result in a wide variety of diseases from cancers to cardiomyopathies. The sHSPs Beta-2 (HspB2) and alpha-beta crystalline (CryAB) are two of the ten human sHSPs and are both expressed in cardiac and skeletal muscle cells. A heart that cannot properly recover or defend against stressors such as extreme heat or cold, oxidative/reductive stress, and heavy metal-induced stress will constantly struggle to maintain efficient function. Accordingly, CryAB is required …


Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen Dec 2013

Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen

Theses and Dissertations

Nanomaterials have attracted substantial attention in the area of catalysis due to the unique properties they exhibit such as high surface areas, intricate pore networks and unique morphologies. TiO2 has attracted attention as a catalyst since the discovery of its high photocatalytic activity by Fuishima and Honda in 1972. Given its high thermal stability, low cost, low environmental impact, and versatility, TiO2 is a widely used commercial catalyst and catalyst support. TiO2 is used in many applications such as photocatalysis is also an excellent support material for noble metals in a number of oxidative synthesis and pollution-control reactions. Though TiO2 …


Real Time Monitoring Of Surface Chemical Events By Streaming Potentials In Microfluidic Channels, Kenji Nokura Dec 2013

Real Time Monitoring Of Surface Chemical Events By Streaming Potentials In Microfluidic Channels, Kenji Nokura

Theses and Dissertations

Zeta potential is one of the tools to measure the surface charge of materials, and Alvarez et al. have developed a microchannel device to measure zeta potentials in real time for label-free sensing using immobilized receptors on microchannel surfaces. However, the challenge has been the charge interference of surface modifiers on analyte detection. Therefore, it was necessary to find the best strategy to regenerate minimal surface charge after modifying the channel with polymer films that would anchor the affinity groups for the analyte. It was demonstrated that adsorption of positively and negatively charged analytes were monitored via real time zeta …


A Comparison Study Of Second-Order Screening Designs And Their Extension, Shane A. Dougherty Dec 2013

A Comparison Study Of Second-Order Screening Designs And Their Extension, Shane A. Dougherty

Theses and Dissertations

Recent literature has proposed employing a single experimental design capable of preforming both factor screening and response surface estimation when conducting sequential experiments is unrealistic due to time, budget, or other constraints. Military systems, particularly aerodynamic systems, are complex. It is not unusual for these systems to exhibit nonlinear response behavior. Developmental testing may be tasked to characterize the nonlinear behavior of such systems while being restricted in how much testing can be accomplished. Second-order screening designs provide a means in a single design experiment to effectively focus test resources onto those factors driving system performance. Sponsored by the Office …


Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson Dec 2013

Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a commonly used separation technique in chemistry. Nevertheless, the mechanistic interactions at the molecular level among the eluent, analyte, and the stationary phase are not fully understood. Because of this limited understanding, optimization of the separation must be done experimentally. Learning more about molecular interactions should aid in improving separations. We are currently using second-harmonic generation (SHG) spectroscopy to investigate how analytes adsorb to the surface. SHG is a spectroscopic technique that produces signal only at places of non-isotropic symmetry; this typically occurs at surfaces. SHG can be used to produce surface isotherms of test …


Discovering Driver Somatic Mutations, Copy Number Alterations And Methylation Changes Using Markov Chain Monte Carlo, Bokhari Yahya Dec 2013

Discovering Driver Somatic Mutations, Copy Number Alterations And Methylation Changes Using Markov Chain Monte Carlo, Bokhari Yahya

Theses and Dissertations

Nowadays we have tremendous amount of genetic data needing to be interpreted. Somatic mutations, copy number variations and methylation are example of the genetics data we are dealing with. Discovering driver mutations from these combined data types is challenging. Mutations are unpredictable and have broad heterogeneity, which makes our goal hard to accomplish. Many methods have been proposed to solve the mystery of genetics of cancer. In this project we manipulate those above mentioned genetics data types and choose to use and modified an existing method utilizing Markov Chain Monte Carlo (MCMC). The method introduced two properties, coverage and exclusivity. …


Exploring Factors That Influence The Choice To Retire From Driving In Older Adults, Debra J. Jenkins Dec 2013

Exploring Factors That Influence The Choice To Retire From Driving In Older Adults, Debra J. Jenkins

Theses and Dissertations

No


Understory Vegetation Response To Mechanical Mastication Of Piñon And Juniper Woodlands, Jordan Ann Bybee Dec 2013

Understory Vegetation Response To Mechanical Mastication Of Piñon And Juniper Woodlands, Jordan Ann Bybee

Theses and Dissertations

Piñon and juniper encroachment and infilling can alter ecosystem processes and decrease resilience and resistance in sagebrush grasslands. Land managers employ a variety of techniques to eliminate these trees and mitigate their negative effects. Mechanical mastication or shredding is an increasingly popular method of removing these trees in Utah. It is a versatile treatment that can reduce canopy fuels, increase infiltration, and reduced sediment loss. We compared vegetation cover for annual and perennial vegetation functional groups on shredded and adjacent unshredded areas across a range of sites. Our approach was to categorize sites by ecological site type (encroachment or tree) …


Synthesis, Characterization, And Functionalization Of Magnetic Iron Nanoparticles For Enhanced Biological Applications, Christopher Warren Dec 2013

Synthesis, Characterization, And Functionalization Of Magnetic Iron Nanoparticles For Enhanced Biological Applications, Christopher Warren

Theses and Dissertations

The transition metal ferrites of composition MFe2O4 where M is Fe, Co, or Ni are well established materials for various biological applications due to their interesting magnetic properties. Their elemental and stochiometric composition can be easily manipulated which allows further tuning of their ferrimagnetic properties. By changing the identity of M and by changing the crystallite size of the ferrites, nanocrystals with diverse magnetic properties can be systematically produced. Furthermore, ferrites are more stable in diverse chemical environments, as compared to metallic nanoparticles, which make ferrites particularly useful for a broad range of biomedical applications, especially in the field of …


Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich Dec 2013

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich

Theses and Dissertations

Although phylloid algal mounds have been studied for 50 year, much remains to be determined concerning the ecology and sedimentology of these Late Paleozoic carbonate buildups. Herein we perform a digital outcrop study of the well-known Middle Pennsylvanian Lower Ismay mound interval in the Paradox Basin because outcropping mounds along the San Juan River are cited as outcrop analogs of reservoir carbonates in the Paradox Basin oil province of Utah and adjacent states. The principal field area is the Eight Foot algal field located at river mile 19.2 on the San Juan River, approximately 14 miles SSW of Bluff, Utah. …


The Response Of Naive Channel Catfish To Chemical Cues Associated With Predation, Marinda Coulter Dec 2013

The Response Of Naive Channel Catfish To Chemical Cues Associated With Predation, Marinda Coulter

Theses and Dissertations

The chemosensory abilities of fishes, are important in order to understand how prey can perceive and avoid predators. Predator-naïve Channel catfish were exposed to four extracts over eight sessions (naïve bass water (NBW), bass that were fed catfish water (BFCW), catfish skin extract (CS), and naïve bass water paired with catfish skin extract (CO)) to determine whether they have an innate predator response to potential chemical cues indicating possible predation risk. Movement was quantified as grid squares crossed, directional changes, and tail beats. Response increased during the first minute following stimulus injection and decreased during the second minute. Channel catfish …


Remembering The Haitian Revolution Through French Texts: Victor Hugo's Bug-Jargal And Alphonse De Lamartine's Toussaint Louverture, Irene Joyce Kim Stone Dec 2013

Remembering The Haitian Revolution Through French Texts: Victor Hugo's Bug-Jargal And Alphonse De Lamartine's Toussaint Louverture, Irene Joyce Kim Stone

Theses and Dissertations

The Haitian Revolution was the first successful slave revolt in history. And even though Haiti declared independence from France in 1804, most French civilization textbooks do not include this important event. From an economic standpoint, France depended on its imports from Saint-Domingue (Haiti's pre-revolutionary name); and from a philosophical standpoint, the slave revolt in Saint-Domingue originated from ideas that came from French philosophers preaching the Rights of Man. Studying the Haitian Revolution within the context of the French Revolution provides a perspective that highlights the complex relationship between France and its colonies as well as religion's displaced role after 1789. …


Multi-Column Multi-Layer Computational Model Of Neocortex, Beata Strack Dec 2013

Multi-Column Multi-Layer Computational Model Of Neocortex, Beata Strack

Theses and Dissertations

We present a multi-layer multi-column computational model of neocortex that is built based on the activity and connections of known neuronal cell types and includes activity-dependent short term plasticity. This model, a network of spiking neurons, is validated by showing that it exhibits activity close to biology in terms of several characteristics: (1) proper laminar flow of activity; (2) columnar organization with focality of inputs; (3) low-threshold-spiking (LTS) and fast-spiking (FS) neurons function as observed in normal cortical circuits; and (4) different stages of epileptiform activity can be obtained with either increasing the level of inhibitory blockade, or simulation of …


Tobramycin Disposition In The Lung Following Airway Administration, Min Li Dec 2013

Tobramycin Disposition In The Lung Following Airway Administration, Min Li

Theses and Dissertations

Tobramycin disposition following airway administration was evaluated by meta-analysis of human data in the literature and, experimentally, using a realistic ex vivo model, the isolated perfused rat lung preparation (IPRL). Pulmonary bioavailability of inhaled tobramycin in published studies was re-evaluated separately for CF and healthy adults, with the drug’s intrinsic pharmacokinetic (PK) parameters obtained from intravenous (IV) studies in the literature. While large variations in tobramycin’s clearance precluded accurate assessment of its bioavailability, the results were indicative of substantial pulmonary absorption, in spite of its hydrophilic and poly cationic properties. To explore its disposition kinetics and mechanisms following airway administration, …


Analysis Of Mathematical Models Of The Human Lung, Cooper Racheal Dec 2013

Analysis Of Mathematical Models Of The Human Lung, Cooper Racheal

Theses and Dissertations

The processes of lung ventilation and perfusion, diffusion, and gas transport make up the system of breathing and tissue oxygenation. Here, we present several mathematical formulations of the essential processes that contribute to breathing. These models aid in our understanding and analysis of this complex system and can be used to form treatments for patients on ventilators. With the right analysis and treatment options, patients can be helped and money can be saved. We conclude with the formulation of a mathematical model for the exchange of gasses in the body based on basic reaction kinetics.


Pharmacokinetics Of Dexamethasone Delivered Via Iontophoresis, Justin Holbrook Rigby Dec 2013

Pharmacokinetics Of Dexamethasone Delivered Via Iontophoresis, Justin Holbrook Rigby

Theses and Dissertations

Study Design: Controlled laboratory study. Objectives: To determine the time course of dexamethasone sodium phosphate (Dex-P) iontophoresis delivery to underlying tissues using microdialysis. Background: The efficacy of iontophoresis at delivering Dex-P through the skin is unknown in humans because of the lack of minimally invasive measurement techniques. Methods: Sixty-four healthy male participants (age = 24.4 ± 3.3 yrs, height = 71.8 ± 2.5 in, weight = 181.8 ± 26.1 lbs) were randomly assigned into one of six groups: 1) 1 mA current, 1 mm probes depth ; 2) 1 mA current, 4 mm probes depth; 3) 2 mA current, 1 …


Who's Your Daddy? A Study Of Extra-Pair Copulation And Mating Behaviors Of Protonotaria Citrea, Morton Catherine Heidrich Dec 2013

Who's Your Daddy? A Study Of Extra-Pair Copulation And Mating Behaviors Of Protonotaria Citrea, Morton Catherine Heidrich

Theses and Dissertations

Mating behavior has a profound impact on reproductive success and the resulting genetic structure of offspring. Extra-pair copulation is a widely observed behavior within avian species. This study explored the genetic effects of mating behaviors of Prothonotary warblers, Protonotaria citrea (Parulidae), using co-dominant microsatellite markers. Prothonotary warblers are migratory songbirds that build nests in cavities, commonly found in wetland habitats. A set of artificial nest boxes were initiated by Dr Robert Reilly in 2002 in Dutch Gap, Chesterfield County Virginia, USA, a tidal tributary off the James River. From this population, 28 nest boxes were surveyed yielding 47 adults and …


Evolving Art In Junior High, Randal Charles Marsh Dec 2013

Evolving Art In Junior High, Randal Charles Marsh

Theses and Dissertations

A junior high teacher and artist altered the curriculum of his Art Foundations II course and his own artistic practice in response to complexity thinking. This teacher-artist-researcher uses the arts-based methodology a/r/tography to make meaning of the relationship between his art and pedagogy. The a/r/tographer explains the impact of complexity on the philosophy of education, a/r/tography as a methodology, and the meaning making that occurred are included. Evolution was used as a methodology for art making and as constraint for developing artworks in the classroom and in the author's own art. The teacher-artist-researcher conceptualizes art as an emergent complex cultural …


Transcriptional Crosstalk Between Helper Bacteriophages And Staphylococcal Aureus Pathogenicity Islands, Kristin Lane Dec 2013

Transcriptional Crosstalk Between Helper Bacteriophages And Staphylococcal Aureus Pathogenicity Islands, Kristin Lane

Theses and Dissertations

Acquisition of a superantigen pathogenicity island (SaPI) significantly increases virulence in Staphylococcus aureus. Horizontal transfer of SaPIs occurs at high frequency and depends upon a helper bacteriophage, either through direct infection or SOS-mediated induction of a lysogen. SaPIs hijack the packaging machinery of the helper phage, leading to the formation of SaPI-containing transducing particles that can introduce the pathogenicity island into neighboring SaPI-negative cells. All SaPIs contain a conserved core of genes, some of which are co-transcribed as an operon and encode functions involved in helper exploitation. The goal of this study was to more fully understand the intricate relationships …