Digital Commons Network^™

Nematicidal Activity Of Extracts From Phytolacca Americana On Five Plant-Pathogenic Nematode Species Of Economic Importance, Saleh Ahmed

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Plant-parasitic nematodes cause significant losses to plant agriculture annually. The limited availability and high cost of synthetic nematicides, along with the environmental risks associated with their use, have created a renewed interest in the search for alternative management tactics. One such alternative tactic is the use of plant extracts. The focus of this research is the evaluation of the nematicidal activity of water extracts from Pokeweed (Phytolacca americana). In vitro and greenhouse tests were performed to evaluate the effects of the extracts on five species of plant-pathogenic nematodes of economic importance: Aphelenchoides fragariae, Ditylenchus dispsaci, Meloidogyne incognita, Pratylenchus penetrans, and …

Objective Bayesian Analysis On The Quantile Regression, Shiyi Tu

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The dissertation consists of two distinct but related research projects. First of all, we study the Bayesian analysis on the two-piece location-scale models, which contain several well-known sub-distributions, such as the asymmetric Laplace distribution, the skewed normal distribution, and the skewed Student-t distribution. The use of two-piece location-scale models is an attractive method to model non-symmetric data. From a practical point of view, a prior with some objective information may be more reasonable due to the lack of prior information in many applied situations. It has been shown that several common used objective priors, such as the Jeffreys prior, result …

Tracking Anisotropic Optical Tracers To Study Biophysical Processes And Cytotoxicity, Khanh Van Nguyen

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We use anisotropic optical tracers (also called magnetically modulated optical nanoprobes – MagMOONs or MOONs for non-magnetic nanoprobes in this dissertation) to study biophysical processes such as enzyme-catalyzed cleavage through tissue, intracellular transport of these tracers and cytotoxicity based on this transport. The anisotropic optical properties cause these tracers to blink when rotating. This blinking is distinguishable from the background and can be tracked on a single-particle level in the absence of tissue, or for an ensemble average of tracers blinking through tissue. An alginate gel containing these tracers in the form of a thin film can be used as …

Examining The Space-Time Constraints Concept On Tourist Behavior For Visitors To The South Carolina Coastal Area Of The United States, Sanghoon Kang

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This dissertation explored three themes with regard to the spatial aspects of tourist behavior, conducting three independent analyses. For these analyses, this dissertation research adapted Shoval's (2012) definition of the space-time constraints concept developed by Hagerstrand (1970): the purpose of trip (i.e., authority constraints), the length of visit (i.e., capability constraints), and the composition of travel party (i.e., coupling constraints). The purposes of the three analyses were to examine the relationships 1) between the space-time constraints and the spatial patterns of travel; 2) between ICT use (i.e., smartphones) and the spatial patterns of travel, space-time constraints, tourists' unplanned destination visits, …

An Examination Of Psychological Climate Linking Mechanisms Across The Strategic Priorities Of Health And Stress, Alec Munc

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Given that employee health and well-being represent a significant source of financial costs for organizations, this dissertation seeks to address some of the pathways through which organizational efforts to improve physical and mental health may operate. This study drew from a model of safety climate (Neal & Griffin, 2000) to propose that psychological climate exerts in influence on employee health and well-being through the joint moderators of knowledge/motivation and behaviors. The model also extended beyond the typical climate linking mechanisms to include moderators both individual (behavioral activation & behavioral inhibition systems) and contextual (workplace physical exposure). Using a two-wave prospective …

Bombardment Simulations And Intercalation Studies Of Carbon Materials, Charles Lowe

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Molecular bombardment experiments have led to the possibility of altering materials with properties not normally associated with those materials. Molecular bombardment leads to defect formation in the material, potentially creating a pore, depending on the material and bombarding molecule. Carbon allotropes, specifically graphite and graphene, make excellent candidates for molecular bombardment experimentation. Depending on the bombarding molecule and the kinetic energy associated with that molecule, the defects induced will be sufficient to create a pore in the graphene. The AIREBO potential is used to simulate a graphene bilayer being bombarded with a single Ar atom, or a fullerene molecule, to …

Iterative Design And Testing Of A Mobile Application To Support Food Consumption Monitoring And Decision Making, Melva James

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Food overconsumption is a major contributor to weight gain leading to obesity. Constant exposure to larger amounts of food and beverage has caused many individuals to experience “portion distortion,” the perception that bigger portion sizes are appropriate for consumption at a single sitting. Independently and accurately changing this perception can be very difficult even if one has a desire to do so. In response to these observations, we developed and tested Picture-Perfect Portions, a mobile application designed to combat overconsumption, at the individual level, by leveraging the power of simple visualizations to help adults understand and adjust their food consumption …

Developing Effective Ground And Space-Based Soil Moisture Sensing Techniques For Irrigating Cotton In Coastal Plain Soils, Xin Qiao

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Irrigation scheduling based on soil moisture sensor readings has gained popularity in the past few decades since it can enhance crop yield while saving water. Such method is limited since the representativeness of an individual soil moisture sensor measurement is questionable in a large field with variable soil type and texture. The optimum location of soil moisture sensors needs to be determined within such a production field for effective sensor-based irrigation scheduling. Therefore, the first object of this study was to investigate the optimum sensor location and the number of moisture sensors required for irrigating cotton in coastal plain soils. …

A Laminated Ring On Elastic Foundation Model With Application To Analysis Of Tire-Road Contact, Chunjian Wang

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A deformable Ring on Elastic Foundation (REF) model has been widely used for modeling rotating structures such as gears, bearings and tires. This dissertation extends the existing work with three main contributions focusing on applications to tires: 1) The elastic foundation is endowed with unilateral stiffness, which leads to a nonlinear deformation dependent stiffness typical of some non-pneumatic tires; 2) The model of the deformable ring is extended from simple Timoshenko rings to a laminated orthotropic ring model, with bending, shear stiffness and extensibility in the internal layer, and transverse stiffness in the external layer; 3) Facilitated by the laminated …

Nutrition Education For Children Attending Preschool (Necap), Ibtehal Alsallaiy

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There is a need to educate children as young as 3-5 years old about nutrition. It is at this age when children start to develop their preferences for certain foods. The purpose of this research study was to; explore the perceptions, preferences, and dietary intake of the main food groups in preschool children, explore the availability, choices, and preparation of the main food groups by the care providers, design and present a nutrition education program to the children and their care providers. The average consumption of fruits during breakfast and lunch prior to the program was 51.6 %, 59.3 % …

Creating Arguments Using A Multiliteracies Approach: A Formative Experiment, Emily Howell

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This dissertation study addresses the New London Group’s (1996) concern that technology and globalization require an expanded concept of literacy that focuses upon the multimodal nature of communication. This study combined a formative experiment with multiple-case-study methods to understand the pedagogical implications of implementing an intervention based upon the multiliteracies perspective (New London Group, 1996), a perspective that remains theoretical in application. This study sought to implement this perspective in a ninth- and a tenth-grade English class in a rural school district and develop assertions that further the localized, pedagogical understanding and application of the present study’s intervention (Gravemeijer & …

Estimating The Effect Of Extended And Emergency Unemployment Benefits On The Long-Term Unemployed, James Jones

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Unemployment insurance is designed to help workers smooth consumption in the event of a negative employment shock. These benefits are traditionally funded and administrated by the individual states and territories of the United States. The depth and severity of the “Great Recession” that started in December of 2007 and ended in June of 2009 was such that, Congress was compelled on multiple occasions to extend those benefits. Legislation during this period extended the duration of unemployment benefits to the longest period in history, as unemployed individuals in many states could receive up to 99 weeks of unemployment compensation. The policy …

Integrated Coherent Combining Of Angled-Grating Broad-Area Lasers: Design, Fabrication And Characterization, Yunsong Zhao

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In this thesis, we proposed, fabricated and demonstrated the coherent beam combining of angled-grating broad-area lasers. We have obtained the simultaneous coherent beam combining and single transverse mode operation completely on chip without any external phase control/components. Since the single transverse mode is the key to obtain diffraction-limit beam quality and high brightness, the proposed design is a good candidate for high power and high brightness applications. In the proposed coherently combined laser array, we use the angled-grating broad-area laser as the building block and overlap the adjacent emitters at one facet. The overlapped region becomes a 2D coupling region. …

Risk Analysis And Disaster Recovery: A Florida Lihtc Case Study, Valerie Hammett

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In spite of numerous programs and policies that encourage private investment in affordable housing, particularly after hurricane disaster, insufficient numbers of affordable units exist to meet demand. Some low-income households are displaced in the course of disaster recovery, and others face severe housing cost burdens as demand for affordable housing outstrips supply. Some suggest competitive uses for limited funds impede production. Others suggest that disaster and recovery policies tend to favor homeowners and economic recovery. Little attention has been given to the development decisions of affordable housing developers during disaster recovery. This study examines LIHTC development risk after the 2004 …

Understanding The Automotive Pedal Usage And Foot Movement Characteristics Of Older Drivers, Yubin Xi

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The purpose of this study was to understand the pedal usage characteristics of older drivers in various driving tasks using an instrumented vehicle. This study stemmed from the prevalence of the pedal application errors (PAEs) and the older drivers’overrepresentation in crashes caused by PAEs.

With the population increasing and becoming older, it is estimated that in 2020 there will be 40 million drivers over the age of 65 in the United States. Compared with their younger counterparts, older drivers are facing declining cognitive and physical abilities, such as impaired vision, slower reaction time and diminishing range of limb motion. Because …

Interacting Partners Of The Sunn Symbiotic Kinase, Ashley Dawn Zearfoss Crook

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The control of nodule number in legumes is primarily accomplished through a complex systemic signaling pathway termed autoregulation of nodulation (AON). The protein kinase SUNN, a leucine-rich repeat receptor-like kinase, exhibits shoot control of AON. I show subcellular localization of SUNN to the plasma membrane and specifically to the plasmodesmata, a prime location for systemic signaling. To aid in better understanding the mechanisms of signaling in AON, I used different approaches to identify potential protein-protein interactions involving SUNN, including candidate genes, exploratory proteomics, and forward genetic screens. Candidate interactors, including CLAVATA2 (CLV2), CORYNE (CRN) and guanine exchange factors of the …

A Framework For Designing Of Electric Vehicle Charging Infrastructure Network, Shengyin Li

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The lack of sufficient public charging stations for electric vehicles has long been recognized as a major hinder for massive adoption of electric vehicles (EV). This dissertation aims to develop a framework for designing charging station infrastructure networks that electric vehicle with limited travel range can be recharge en-route to complete trips to destinations and then would facilitate the adoption of electric vehicles. The rest part of this dissertation is concerned with modeling travel range of electric vehicle and users behavior of deviating from their most preferred routes when siting charging stations. The proposed multi-path refueling location model provides the …

In Vitro Multi-Scale Patient-Specific Modeling Of Hemodynamics In Stage 1 Norwood Palliation For The Treatment Of Single Ventricle Heart Disease, Tianqi Hang

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Hypoplastic left heart syndrome (HLHS) is a congenital heart defect in which the left ventricle is severely underdeveloped. The Norwood procedure is the first stage procedure to make an unrestrictive systemic blood flow and at the same time balance it with the pulmonary flow. This is done by constructing a neo-aorta using the pulmonary artery root and the autologous aorta, and then installing a shunt to the pulmonary artery. Variations of the Norwood surgery include the modified Blalock-Taussig (mBT) shunt, which diverts blood from the innominate artery to the pulmonary artery (PA), and the Right Ventricle Shunt (RVS), which diverts …

Nursing Interruption Dynamics: The Impact Of Work System Factors, Yushi Yang

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Interruptions occur frequently in healthcare work systems. Hands-free Communication Devices (HCDs) were implemented in healthcare work systems to support the interruption process. However, from a sociotechnical systems perspective, HCDs may introduce new complications and unintended consequences to the work system. Research gaps exist in investigating the complexity of HCD interruptions in the real-world context. This dissertation aims to understand HCD interruption dynamics in the nursing work systems, using qualitative research methods. The first study examined the major differences between face-to-face and HCD-mediated interruptions, based on 30 hours of field observations in the acute care setting. Three major differences included: (1) …

A Study On General Assembly Line Balancing Modeling Methods And Techniques, Bryan Pearce

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The borders of the assembly line balancing problem, as classically drawn, are as clear as any other operations research topic in production planning, with well-defined sets of assumptions, parameters, and objective functions. In application, however, these borders are frequently transgressed. Many of these deviations are internal to the assembly line balancing problem itself, arising from any of a wide array of physical or technological features in modern assembly lines. Other issues are founded in the tight coupling of assembly line balancing with external production planning and management problems, as assembly lines are at the intersection of multiple related problems in …

Robust Model Development For Evaluation Of Existing Structures, Saurabh Prabhu

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In the context of scientific computing, validation aims to determine the worthiness of a model in supporting critical decision making. This determination must occur given the imperfections in the mathematical representation resulting from the unavoidable idealizations of physics phenomena. Uncertainty in parameter values furthers the validation problems due to the inevitable lack of information about material properties, boundary conditions, loads, etc. which must be taken into account in making predictions about structural response. The determination of worthiness then becomes assessing whether an unavoidably imperfect mathematical model, subjected to poorly known input parameters, can predict sufficiently well in its intended purpose. …

Development And Validation Of A Novel In Vitro Model For The Assessment Of Heterocellular Interactions Mediated By Connexin43, Emily Ongstad

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The injury border zone (IBZ), a region of transitional tissue between intact myocardium and the ischemic area, is often the site of lethal reentrant arrhythmia generation in post-myocardial infarction (MI) patients. Disruption to normal connexin43 (Cx43) localization at the intercalated disc (ID), separation of myocytes by activated fibroblasts and deposited scar tissue are thought to be factors that render the IBZ a pro-arrhythmic substrate, though there is a current need to better understand these changes so directed therapies can be developed. There are no clinically available therapies focused on the mechanistic changes in the IBZ. Additionally, generation of new compounds …

The Creation And Validation Of An Instrument To Measure School Stem Culture, Christopher White

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Although current research exists on school culture, there is a gap in the literature on specialized aspects of culture such as STEM Culture defined as the beliefs, values, practices, resources, and challenges in STEM fields (Science, Technology, Engineering and Mathematics) within a school. The objective of this study was to create a valid and reliable instrument, the STEM Culture Assessment Tool (STEM-CAT), that measures this cultural aspect based on a survey of stakeholder groups within the school community and use empirical data to support the use of this instrument to measure STEM Culture. Items were created and face validity was …

Evaluation Of Blue Tilapia (Oreochromis Aureus) For Duckweed (Lemna Minor) Control In South Carolina's Private Waters, William Heaton

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ABSTRACT We investigated the potential of Blue Tilapia (Oreochromis aureus) as a means for biological control of duckweed in agricultural impoundments, and assessed the potential for naturalization of this non-native fish in coastal regions of South Carolina. Additionally, we studied growth characteristics and nutrient accumulation abilities of duckweed (Lemna minor) growing in agricultural impoundments in the piedmont and coastal plain. Observations of tank feeding trials indicated juvenile Blue Tilapia consumed 36 – 86% of their body weight in fresh duckweed every 24 hours. Tilapia were stocked in agricultural impoundments in the piedmont and coastal plain during the 2012 and 2013 …

Anisotropic Stimuli-Responsive Polymeric Nanoparticles: Synthesis And Characterization, Chunliang Lu

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This dissertation focuses on the design, synthesis and characterization of stimuli-responsive anisotropic nanoparticles with various morphologies. Size- and shape-tunable Janus nanoparticles consisting of poly(methyl methacrylate/n-butyl acrylate) (p(MMA/nBA)), poly(pentafluorostyrene/nBA) (p(PFS/nBA) and poly(2-(N,N′-dimethylamino) ethyl methacrylate/nBA) (p(DMAEMA/nBA)) phases were synthesized via consecutive seeded emulsion polymerization. These Janus nanoparticles are capable of changing size and morphology in response of temperature and/or pH changes, which may have potential applications as solid surfactants. Gibbous and inverse-gibbous nanoparticles were synthesized viacopolymerization of fluorinated monomers in the presence of pMMA or polystyrene (pSt) seed particles. The morphology of the gibbous nanoparticles can be controlled by polymerization conditions. Incorporation …

Leisure, Obesity And Weight Loss: An Exploration Of Leisure, The Public Health Ecological Model Of Obesity And Identity Theory, Weber Player

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Obesity is a global health crisis with complex causal relationships. From the mid 1990s to 2010, obesity related research in the clinical and social sciences has exploded. This expansion has resulted in a proliferation of obesity-related articles published in top-tier journals and the creation of new journals solely devoted to obesity research. In contrast within leisure scholarship, a review of leisure journals reveals that published research on the relationship of leisure, obesity and weight loss is minimal. However, numerous leisure scholarship/theory principles are relevant to obesity prevention and treatment. Similarly, public health officials have developed numerous systems-oriented multilevel framework models …

A Special Protection Scheme Utilizing Trajectory Sensitivity Analysis In Power Transmission, Dan Suriyamongkol

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In recent years, new measurement techniques have provided opportunities to improve the North American Power System observability, control and protection. This dissertation discusses the formulation and design of a special protection scheme based on a novel utilization of trajectory sensitivity techniques with inputs consisting of system state variables and parameters. Trajectory sensitivity analysis (TSA) has been used in previous publications as a method for power system security and stability assessment, and the mathematical formulation of TSA lends itself well to some of the time domain power system simulation techniques. Existing special protection schemes often have limited sets of goals and …

High Temperature Synthesis And Characterization Of Reduced Polyoxometalate Salt-Inclusion Solids, Dino Sulejmanovic

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Herein, several new salt-inclusion solids (SISs) featuring electronically reduced Keggin polyoxometalate (POM) clusters were isolated for the first time using molten-salt high temperature (> 500 oC) synthetic method. These POM-based SISs are novel all-inorganic materials featuring an integrated lattice of ionic halide salt and covalent metal oxide clusters. Due to the weak interactions at the interface between these two chemically dissimilar lattices, these POM SISs are soluble in aqueous and polar solvents. While POM compounds are well-studied and are routinely synthesized in solution, the synthetic method presented in this dissertation yielded several POM solids with interesting structures and infrequently observed, …

Towards A Greater Understanding Of Hydrothermally Grown Garnets And Sesquioxide Crystals For Laser Applications, Cheryl Moore

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ABSTRACT The hydrothermal method of crystal growth offers many benefits over traditional melt-based techniques such as lower temperature requirements relieving detrimental high temperature effects such as stress fracturing and a closed-environment, which limits impurities. The continued study of this type of growth including hydrothermal epitaxy is crucial in our world of constant miniaturization. Presented in this thesis is the hydrothermal growth of crystals of LuAG and Lu2O3 doped with a variety of dopants. Their room-temperature and cryogenic absorption spectra are also presented. Much like Nature uses heat, pressure, water and a nutrient-rich feedstock we have used this hydrothermal technique to …

Development Of A Miniaturized Ambient Glow Discharge Ionization Source And Its Application In Elemental And Molecular Analysis, Xinyan Zhang

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Since the liquid sampling-atmospheric pressure glow discharge (LS-APGD) was first developed as an excitation source for atomic emission spectroscopy, it has been improved upon and demonstrated as an ionization source for elemental mass spectrometry, molecular mass spectrometry, and ambient desorption mass spectrometry. Multiple functions coming from one package allowed the LS-APGD to hold a unique position among all atmospheric pressure glow discharges. It also has the capabilities to work with different sample forms including liquids, bulk solids, and solution residues. The high salt/matrix tolerance reduces sample prep work and thus provides convenience for its potential use as a field-Based ionization …