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Reniform Nematode (Rotylenchulus Reniformis) Manipulation Of Host Root Gene Expression During Syncytium Formation In Upland Cotton (Gossypium Hirsutum), Wei Li

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Background: The semi-endoparasitic reniform nematode (Rotylenchulus reniformis) is a major yield-limiting pest of multiple crops in the tropics and sub-tropics, including upland cotton (Gossypium hirsutum). Reniform-resistant cotton varieties are urgently needed, but genes that confer resistance to reniform nematode have not been identified in any species. Parasitism by reniform nematode involves significant developmental changes in plant roots, leading to the formation of multicellular feeding structures called syncytia. Here, we present de novo transcriptomes assembled from syncytial and non-syncytial cotton roots on three sampling dates across a 12-day time course. Results: Total mRNA samples extracted from reniform-infected …

Earth Abundant Thin Film Technology For Next Generation Photovoltaic Modules, Githin Alapatt

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With a cumulative generation capacity of over 100 GW, Photovoltaics (PV) technology is uniquely poised to become increasingly popular in the coming decades. Although, several breakthroughs have propelled PV technology, it accounts for only less than 1% of the energy produced worldwide. This aspect of the PV technology is primarily due to the somewhat high cost per watt, which is dependent on the efficiency of the PV cells as well as the cost of manufacturing and installing them. Currently, the efficiency of the PV conversion process is limited to about 25% for commercial terrestrial cells; improving this efficiency can increase …

Unusually Low Thermal Conductivity In The Argyrodite Ag8gete6 Attributed To Strong Anharmonicity, Dale Hitchcock

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Arguably the main focus of thermoelectric materials research over the last decade has been the reduction of lattice thermal conductivity through nanostructuring. This approach has proved quite effective in many instances, but has several inherent drawbacks including not only the metastability of many of the nanostructures used, but also difficulty decoupling the effects on the thermal properties of materials from the effects on their electrical properties. Some more recent research has focused on reduced thermal conductivity in materials with strong anharmonicity. In these systems anharmonicty in the crystal structure, whose strength can be gauged by the so-called Gruneissen parameter leads …

Steps Toward A Net-Zero Campus With Renewable Energy Resources, Andrew Clarke

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With the increasing attention and support behind plug in hybrid electric vehicles, research must be conducted to examine the impacts of vehicles on electric distribution and transmission systems. This research aims first to model the behavior of vehicle battery chargers during system disturbances and mitigate any impacts. A distribution test system example is modeled and several different vehicle charger topologies are added. Faults are applied to the distribution system with vehicle chargers connected and the results are examined. Based on these results, a control strategy to mitigate their negative impacts is suggested. Photovoltaic panels are then added to the system …

Development Of A Translational, Tissue-Engineered Approach To Replacement Of Myocardial Infarct Scar Tissue, Jason Schulte

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Myocardial infarction (MI) affects nearly 600,000 individuals each year, and the resulting damage initiates a pathophysiological progression towards congestive heart failure (CHF). A shortage of donor organs precludes heart transplantation as a practical solution, and neither surgical intervention nor stem cell therapy have yielded consistent and sufficiently positive results in clinical investigation. To prevent CHF, prospective therapies must target the cause of the maladaptive cardiac remodeling which precedes it--the nonfunctional, dyskinetic infarct scar--and aim to replace it with functional cardiac muscle. Tissue engineering holds promise for the development of novel therapies to either halt or reverse post-MI cardiac remodeling. However, …

Empowering Citizens In A Global Era: A Grounded Theory Study Of Community Gardens, Anita Tam

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In our global era, the modern food system can be viewed as consisting of a dominant macro-level corporate food industry, challenged by broad-based meso-level food justice and democracy movements, which are in turn fueled by micro-level community food initiatives. Research has yet to examine the role of community gardens in the context of this complex, multi-level food system. Grounded theory methodology was thus used to explore the deeper meaning of the community gardening experience to participants, in order to better understand the ways in which community gardens may scale up and contribute to democratizing the food system. Analysis of the …

Autonomous Control And Automotive Simulator Based Driver Training Methodologies For Vehicle Run-Off-Road And Recovery Events, Paul Freeman

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Traffic fatalities and injuries continue to demand the attention of researchers and governments across the world as they remain significant factors in public health and safety. Enhanced legislature along with vehicle and roadway technology has helped to reduce the impact of traffic crashes in many scenarios. However, one specifically troublesome area of traffic safety, which persists, is run-off-road (ROR) where a vehicle's wheels leave the paved portion of the roadway and begin traveling on the shoulder or side of the road. Large percentages of fatal and injury traffic crashes are attributable to ROR. One of the most critical reasons why …

The Facilitated Individualized Education Program Process: State Perspectives, Jennifer Wagner

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Conflict between parents and school personnel continues to be an area of concern for students with disabilities, despite efforts by lawmakers to provide more parental input into the process of identification and continuation of special education services. Recent data suggest that unresolved conflict at the local level can cost a school district thousands of dollars to resolve the conflict in court, without consideration to the emotional costs that can be involved with this type of conflict resolution. Through mandates from IDEA 2004, alternative dispute resolution (ADR) strategies, such as facilitated individualized education program (FIEP) meetings, have been utilized to reduce …

The Development And Characterization Of Tannic Acid Cross-Linked Collagen Scaffolds For The Prevention Of Breast Cancer Recurrence In Lumpectomy Patients, Beau Inskeep

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Breast cancer is the second most common cancer amongst women, second only to lung cancer. In 2014, it was estimated that there were approximately 295,000 new cases of breast cancer diagnosed in women, with approximately 40,000 deaths caused by breast cancer in the United States. It has been reported that a woman has a 12% chance of developing breast cancer in her lifetime and a 3% chance of dying from breast cancer. There are several treatment options available for breast cancer, including chemotherapy, radiation therapy, as well as two different forms of surgery, mastectomy and lumpectomy. However, none of these …

Chasing Polys: Interdisciplinary Affinity And Its Connection To Physics Identity, Tyler Scott

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This research is based on two motivations that merge by means of the frameworks of interdisciplinary affinity and physics identity. First, a goal of education is to develop interdisciplinary abilities in students' thinking and work. But an often ignored factor is students interests and beliefs about being interdisciplinary. Thus, this work develops and uses a framework called interdisciplinary affinity. It encompasses students interests in making connections across disciplines and their beliefs about their abilities to make those connections. The second motivation of this research is to better understand how to engage more students with physics. Physics identity describes how a …

Effects Of Transportation Hazards On Package Performance And Food Product Shelf Life, Kyle Dunno

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This research studied the effect of transportation hazards on food product shelf life and package performance. Studies were conducted to determine the effect of package headspace volume, product viscosity and storage temperature on package integrity. Finally, accelerated shelf life testing (ASLT) was utilized to determine how simulated transportation hazards affected the shelf life of a specific food product. Institutional retort pouches containing either water or 5% starch solution were filled with varying amounts of headspace volume to determine if package headspace volume could aid in package performance during simulated engineering tests for packaged products. Fixed displacement vibration testing and compression …

Targeted Delivery Of Anti-Inflammatory And Anti-Oxidant Drugs For Treatment Of Chronic Obstructive Pulmonary Diseases, Yun Xiang

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Chronic obstructive pulmonary disease (COPD) was found to be the fourth leading cause of death in 2004, but current treatments can only relieve the symptoms and improve the quality of life for the patients. Glucocorticoids have been broadly applied in other inflammatory conditions with promising therapeutic effects, but performed poorly in COPD. The phenomenon called glucocorticoid resistance is responsible for glucocorticoid insensitivity in COPD. Researchers have proven that elevated oxidative stress in the lung of a COPD patient is one of the main causes of blocking the function of glucocorticoids. We hypothesize that reducing the oxidative stress in the lung …

Robust Design Of Shield Tunnels ‒ Considering The Longitudinal Variation Of Input Parameters, Wenping Gong

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This dissertation, aimed at developing an improved design methodology for shield tunnels that explicitly considers design robustness against longitudinal variation of input parameters (such as soil parameters). To this end, a new solution model for shield tunnel performance analysis was first developed. In this new model, the random field concept was employed to model the longitudinal variation of input parameters. The input parameters (in the longitudinal domain) that had been generated with Monte Carlo simulation (MCS) were used as inputs for the tunnel longitudinal behavior analysis. Here, the finite element method (FEM) based upon Winkler elastic foundation theory was employed. …

Nonequilibrium Transport Of Ionic Liquids In Electrified Nanosystems, Xikai Jiang

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Room-temperature ionic liquids (RTILs) are a promising class of electrolyte that are composed entirely of ions but are liquid at room temperature. Their remarkable properties such as wide electrochemical window make them ideal electrolytes in many electrochemical systems. Because the non-equilibrium transport of RTILs often determines the performance of these systems, a fundamental understanding of such transport is needed. Here, using molecular dynamic (MD) and continuum simulations, we investigated the non-equilibrium transport of RTILs in three scenarios relevant to the application of RTILs in electrochemical systems: the electroosmotic flow (EOF) of RTILs through nanochannels, the electrokinetic transport of RTILs through …

Particle Scavenging By Water Drops In An Ultrasonic Standing Wave Field, Weiyu Ran

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Currently the backbone of the world's energy supply is composed of fossil fuels. However, the combustion of fossil fuels results in the production of enormous quantities of particulate pollutants. The smog resulting from these particulate pollutants causes significant health problem for city dwellers. Wet scrubbers, which use a water spray to scavenge airborne particles, is one of the most widely used devices to control particulate pollutants. Typical wet scrubbers can scavenge particles with diameters bigger than 10 um, but it is inefficient in scavenging particles with diameters on the order of 1 um. Unfortunately these fine particles are more dangerous …

The Influence Of Mindfulness During The Travel Anticipation Phase On Search And Choice Behaviors, Search And Choice Outcomes, And Trip Evaluations, Lorraine Taylor

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Anticipation is the first travel phase (Clawson & Knetsch, 1966) and consists of the vacation planning process. Tourists may exhibit varying levels of mindfulness during this phase. Mindfulness is associated with analytic decision making through a heightened sensitivity to one's environment and openness to new information (Langer & Moldoveanu, 2000). This study considered the influence that mindfulness during the travel anticipation phase has on: search and choice behaviors, search and choice outcomes, and trip evaluations. Analysis was also conducted to determine if there was a significant influence on the relationships based on the mediating effect of the amount of the …

Rebuilding Social Organization In Low-Income Neighborhoods: The Influence Of Habitat For Humanity, John Lattimore

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Research has linked neighborhoods of concentrated poverty with high crime, low employment, poor health, and low educational achievement. Because of these linkages, federal housing policy over the past few decades has often tried to 'deconcentrate' or disperse the poor from these neighborhoods into more affluent neighborhoods with the hope that better institutions and better neighbors will motivate these families to improve their lives. However research on large mobility programs such as Gautreaux and Moving to Opportunity (MTO), has found mostly mixed results and criticized the programs for having a small impact. Race and income have also proven to be significant …

Surface Modifications Of Capillary-Channeled Polymer (C-Cp) Fiber Stationary Phases: Improving The Efficiency Of Highly Selective Analyte Separations, Abby Schadock-Hewitt

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High performance liquid chromatography (HPLC) is a fundamental methodology for the characterization and purification of macromolecules. Since its development in the 1970's, HPLC has significantly advanced its instrumentation and column technology to become a powerful analytical technique. A considerable amount of research focuses on advancements to the stationary phase, or solid support, on which molecules interact and separate. To overcome limitations of other phases that lead to poor mass transfer, slow speeds, and low efficiency, nonporous and superficially porous phases have been developed. Specifically, fiber based polymer stationary phases show great promise as stationary phases for protein separations. The Marcus …

Investigating The Effects Of Biochemical And Biophysical Signals On Vascular Smooth Muscle Cell Differentiation, Ruikai Chen

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In blood vessel engineering, an optimal bioartifical scaffold can be characterized as a 3D tubular structure with high porosity for nutrient diffusion and enough mechanical strength to sustain in vivo dynamic environment. The luminal surface of the scaffold is supposed to have a continuous layer of endothelial cell that is ideally non-immunogenic and non-thrombogenic while the media layer of the construct is assigned for the ingrowth of vascular smooth muscle cell which can provide structural integrity and contractility. While reconstructing endothelial cell layer has been at the center of interest in most polymeric vascular replacements related research, growing VSMCs has …

Thermally Responsive Polymer Electrolytes For Inherently Safe Electrochemical Energy Storage, Jesse Kelly

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Electrochemical double layer capacitors (EDLCs), supercapacitors and Li-ion batteries have emerged as premier candidates to meet the rising demands in energy storage; however, such systems are limited by thermal hazards, thermal runaway, fires and explosions, all of which become increasingly more dangerous in large-format devices. To prevent such scenarios, thermally-responsive polymer electrolytes (RPEs) that alter properties in electrochemical energy storage devices were designed and tested. These RPEs will be used to limit or halt device operation when temperatures increase beyond a predetermined threshold, therefore limiting further heating. The development of these responsive systems will offer an inherent safety mechanism in …

Modeling Sustainability In Renewable Energy Supply Chain Systems, Fei Xie

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This dissertation aims at modeling sustainability of renewable fuel supply chain systems against emerging challenges. In particular, the dissertation focuses on the biofuel supply chain system design, and manages to develop advanced modeling framework and corresponding solution methods in tackling challenges in sustaining biofuel supply chain systems. These challenges include: (1) to integrate 'environmental thinking' into the long-term biofuel supply chain planning; (2) to adopt multimodal transportation to mitigate seasonality in biofuel supply chain operations; (3) to provide strategies in hedging against uncertainty from conversion technology; and (4) to develop methodologies in long-term sequential planning of the biofuel supply chain …

Materials Science Of Electrochemical Formation Of Tungsten Nanosharp Probes, Maryana I. Nave

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This dissertation is centered on the development of a methodology that aims to engineer millimeter long and ten microns thin nanosharp tungsten probes. The current state of the art of electropolishing techniques is reviewed. We discuss the probes produced by electrochemical etching of a wire until it breaks into two pieces. This process is difficult to control because of the complexity of the associated hydrodynamic flows. These techniques were called convection-limited electropolishing (CLE) because the kinetics of wire etching is controlled by the convective diffusion of ions. We introduced a newly developed technique, precipitation-limited electropolishing (PLE), which enables production of …

Perceived Health Status, Health Values And Health Goals As Influences On Individual Pursuit Of Dtc Genome Testing: Implications For Healthcare Of Ill & Healthy, Carolyn Marie Dachs Farrell

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This dissertation examines an individual’s perceived health status, and health values, as influences on self-initiated health action, specifically the pursuit of Direct-to-consumer (DTC) genome testing. Motivation for this independent health action may also have implications for other individual health behaviors, including the potential for positive changes that are lasting rather than temporary. Health Capability, the conceptual framework, supports individual health values and goals, ability to access valued healthcare services and includes measures of health status. However, Health Capability lacks an operationalized mapping of its major concepts. This dissertation proposes and evaluates an original concept mapping and relationships. An overview of …

Structure-Property Relationship Of Nanomodified Mesophase Pitch-Based Carbon Fibers, Rebecca Marie Alway Cooper

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Mesophase pitch-based carbon fibers are known for their excellent thermal and electrical conductivity, high tensile modulus, moderate tensile strength, but poor compressive strength. This collection of properties results from the texture and crystalline structure (together known as microstructure) of the fibers. Fiber microstructure, in turn, develops during processing due to the discotic nature of the mesophase pitch precursor. In prior studies, such important parameters as the size and shape of capillaries in the spinneret, spinning temperature and carbonization temperature have been varied to produce fibers with different microstructures and properties. In this dissertation, the primary research goal was to investigate …

Development Of A Transport System For Advancing Tissue Engineering And Cell Identification, Suzanne Mae Tabbaa

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This work centers on the development of a novel passive transport system for two tissue engineering applications – cell distribution and cell separation. This approach relies on a wicking fiber-based system, derived from the textile field that functions by directing and maintaining transport of cells as well as fluids and biomolecules. This system has the ability to enhance cell movement for both the purpose of cell seeding distribution as well as to isolate specific cell types from heterogeneous cell populations.

The success of spinal fusions and large bone defects is often limited by the decreased surrounding vasculature and the ability …

Relationship Between Peel Force, Opening Force, And Burst Force For A Semi-Rigid Cup And Lid, Pre- And Post-Retort, Raj Navalakha

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This research determines if there is any relationship between the peel force, the opening force and the burst force for a semi-rigid cup and lid system, for pre- and post-retort conditions. It also compares the relationship (regression lines) between these forces pre- and post-retort. These seal results were studied by varying the sealing parameters of dwell time and temperature while keeping the pressure constant. Polypropylene cups and a peelable barrier retort lidding were used in this study. As compared to past research, a different peel testing technique was used to measure the peel and the opening force. The entire lid …

Arsenic Targets Neural Plate Border Specifier Cells In P19 Cells, Christopher Mccoy

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Epidemiological studies have shown that arsenic exposure during early embryogenesis can cause reduced weight gain and neurological deficits later on in life. In addition, in vitro and in vivo studies have indicated that arsenic suppresses neurogenesis and myogenesis. The exact mechanism of how arsenic causes these undesired developmental outcomes is poorly understood, however both skeletal muscle and sensory neuron development require the Wnt/β-catenin signaling pathway to initiate the specific differentiation of precursor cells. We were interested in determining the target cell population of arsenic and its metabolites. Arsenic's metabolites were of interest because they have been shown to be more …

Charitable Donations: An Analysis Of The Differences In Donation Patterns By Income Level, Elizabeth Ficklin

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This thesis examines the possibility of grouping charitable donors by income level to develop a set of models that can more accurately predict charitable donations. Previous work is inconsistent in predicting charitable donations. This work helps to determine if these inconsistencies are a result of methodological differences between researchers, or if group membership is an important factor in predicting charitable donations as suggested by some researchers. This research only found four variables that were common to all three income groups, frequency of church attendance, family income, age, and years of education. Results show that additional variables can serve as predictors …

Satisfaction With Work-Family Balance Among Employed Graduate Students: Why Support May Matter More Than Conflict, Brooke Allison

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Previous research suggests that work-family conflict is associated with negative attitudinal and health outcomes. However, few empirical studies have examined the ways in which employee work-family conflict may also decrease another important attitude, satisfaction with work-family balance. Drawing upon role theory and the Conservation of Resources (COR) model, the current paper examined prospective antecedents and outcomes of perceived satisfaction with work-family balance among 523 graduate student employees. Results indicated that work-family conflict mediated and moderated the demands-satisfaction relationship, and that mentor work-family support affected how work-family conflict influenced satisfaction with work-family balance. Results suggest that graduate student satisfaction with work-family …

Investigation Of Electrical Component Failures Affecting Vehicle Electronics, Dexin Zhang

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This dissertation describes three independent studies related to electrical component failures affecting vehicle electronics. The topics covered are: comparison of the accelerator-pedal-to-engine-control module (AP-to-ECM), the effect of electrical fast transients on multi-layer ceramic (MLC) capacitors, and electrical behavior of MLC capacitors damaged by electrostatic discharge.

The first chapter examines the AP-to-ECM interfaces of five vehicles equipped with electronic throttle control systems. All five vehicles employ simple voltage level sensing from two or three sensors in the accelerator pedal assembly. The purpose of the study is to identify any differences in the AP-to-ECM interfaces of vehicles with high reported rates of …