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Quantification Of Risk For Usaf Fire And Emergency Services Flights As A Result Of Shortage In Manpower, Timothy D. Dalby

Theses and Dissertations

The United States Air Force (USAF) is currently experiencing a period of high operations tempo and overseas deployments have become frequent. These deployments will leave home installations short manned. Some amount of risk is incurred by the home installation as a result of the short manning. For an organization, such as an USAF Fire and Emergency Services (FES) flight, whose primary responsibility is the protection of life and property, the incurred risk could be catastrophic. Still no attempt has been made to quantify risk in terms of manpower for the USAF FES flights. The primary purpose of this research was …

The Chaos Of Katrina: A Nonlinear Analysis Of Federal Logistics Support During Hurricane Katrina Relief Operations, Gerald W. Morris Jr.

Theses and Dissertations

This thesis presents a case study of federal logistics support during Hurricane Katrina disaster relief operations. Data from federal contracts covering the first 10 weeks of Katrina are used to measure federal logistics activity. The study investigates whether chaos theory, part of complexity science, can extract information from Katrina contracting data to help managers make better logistics decisions during disaster relief operations. The study uses three analytical techniques: embedding, fitting the data to a logistic equation, and plotting the limit-cycle. Embedding and fitting a logistic equation to the data were used to test for deterministic chaos. The logistic equation and …

Computer Simulations Of Glyceraldehyde -3 -Phosphate Dehydrogenase Interactions With Actin And Fructose -1,6 -Bisphosphate Aldolase, And Substrate Binding Dynamics, Victor F. Waingeh

Theses and Dissertations

The association of glycolytic enzymes with cytoskeletal proteins such as actin is thought to be a structural basis for compartmentation of the glycolytic pathway. It is also suggested that such interactions bring glycolytic enzymes within close proximity to each other so that substrate transfer between sequential enzymes is faster. Brownian dynamics (BD) simulations were used to study the binding of glyceraldehydes-3-phosphate dehydrogenase (GAPDH) to actin and fructose- 1,6-bisphosphate aldolase (aldolase) in different species, and the dynamics of substrate binding. High-resolution three-dimensional models of the proteins used in the simulations were either obtained from X-ray structures or built by homology modeling. …

Kinetics And Mechanism Of The Reaction Of Cobalt Tetrasulfophthalocyanine With Thiolates In The Merox Process, Eduard M. Tyapochkin

Theses and Dissertations

Binding and kinetic studies of the thiolates/thioacid salts complexation with cobalt tetrasulfophthalocyanine (CoIITSPc) in aqueous solutions, dimethylformamide (DMF), and other polar aprotic solvents were conducted using UV-vis, 1H NMR, and ESR methods under anaerobic conditions. In DMF thiolates react with CoIITSPc with 1:1 stoichiometry. Aliphatic thiolates, regardless of their basicity, reduce Co IITSPc to CoITSPc. Low-basicity thiolates form unstable (RS-)CoIITSPe complexes as dead-end products. Indirect kinetic evidence was obtained for the electron transfer from the axial ligand to metal via the phthalocyanine equatorial ligand. 1H NMR and binding studies revealed sulfur-cobalt interactions in the CoITSPc product, indicating axial ligand attachment …

Stratification Of Southern Georgia Streams For Rapid Bioassessment Focusing On Differences In Structure And Function Of Black Water And Clear Water Streams, Salini Pradeep Pillai

Theses and Dissertations

As part of a rapid bioassessment project for the state of Georgia, relatively unimpaired reference streams and impaired sites were sampled for biological, chemical and physical parameters, and macroinvertebrates were identified. The metrics, biological, physical and chemical metrics, were selected using Ecological Data Application System Version 3.3.2k (EDAS). Discrimination efficiency and correlations were performed to determine the best metrics that separated impaired streams from reference streams and later on to form the index of stream water quality. Principal components analysis of the selected metrics showed that some of the blackwater reference streams and clearwater reference streams are randomly placed over …

An Investigation Of Methods To Homogeneously Entrain And Suspend Abrasive Particles In A Low Pressure Dental Water Jet, Michael Sean Grygla

Theses and Dissertations

During the past several decades, the water jet cutting concept has developed from a novel concept into a well-accepted machine cutting tool. With the addition of abrasive particles and the improvement of high pressure pumps, the water jet stream is currently capable of cutting through metal, concrete, and composite materials. Water jet systems have been utilized at a wide range of different pressures. Research performed at Brigham Young University has revealed that low pressure water jets have the ability to cut human teeth. Experiments have shown that when abrasive particles are added to the water jet stream, an greater amount …

An Analysis Of The Subjective Socioeconomic Scale Among Hispanic Immigrants And Caucasians, Mathew Glen Bowden

Theses and Dissertations

Subjective socioeconomic status (SES) has previously been shown to be correlated with a large number of health measures. In this study, the subjective SES measure is modified and translated to measure childhood SES. The subjective SES scale is examined in a participant's hometown, community, and nation. Both an immigrant Hispanic and a Caucasian sample were studied (31 Hispanic males; 42 Hispanic females; 38 Caucasian males, 40 Caucasians females). Childhood SES was the most significant predictor of self-reported health in both sample groups.

High-Frequency Ultrasound Drug Delivery And Cavitation, Mario Alfonso Diaz

Theses and Dissertations

The viability of a drug delivery system which encapsulates chemotherapeutic drugs (Doxorubicin) in the hydrophobic core of polymeric micelles and triggers release by ultrasound application was investigated at an applied frequency of 500 kHz. The investigation also included elucidating the mechanism of drug release at 70 kHz, a frequency which had previously been shown to induce drug release. A fluorescence detection chamber was used to measure in vitro drug release from both Pluronic and stabilized micelles and a hydrophone was used to monitor bubble activity during the experiments. A threshold for release between 0.35 and 0.40 in mechanical index was …

Telomerase Inhibition And Sensitization Of Breast Tumor Cells, Kennon R. Poynter

Theses and Dissertations

Telomerase, a ribonucleoprotein enzyme minimally composed of an RNA template (hTR) and a catalytically active protein subunit (hTERT), synthesizes telomeric repeats onto chromosome ends and is obligatory for continuous tumor cell proliferation, as well as malignant progression of breast cancer cells. Telomerase is an attractive anticancer therapeutic target because its activity is present in over 90% of human cancers, including more than 95% of breast carcinomas, but undetectable in most somatic cells. Traditions chemo- and radio-therapies lack the ability to effectively control and cure breast cancer, in part because residual cells are or become resistant to DNA damaging modalities.While various …

Addressing Issues In The Detection Of Gene-Environment Interaction Through The Study Of Conduct Disorder, Elizabeth Prom-Wormley

Theses and Dissertations

This work addresses issues in the study of gene-environment interaction (GxE) through research of conduct disorder (CD) among adolescents and extends the recent report of significant GxE and subsequent replication studies. A sub-sample of 1,299 individual participants/649 twin pairs and their parents from the Virginia Twin Study of Adolescent and Behavioral Development was used for whom Monoamine Oxidase A (MAOA) genotype, diagnosis of CD, maternal antisocial personality symptoms, and household neglect were obtained. This dissertation (1) tested for GxE by gender using MAOA and childhood adversity using multiple approaches to CD measurement and model assessment, (2) determined whether other mechanisms …

The Effect Of 1,25-Dihydroxy Vitamin D3 On At1 Cell Receptor Expression In Human Iliac Artery Endothelial Cells (Hiaec), Jenny Thomas

Theses and Dissertations

The renin-angiotensin system (RAS) plays an important part in homeostasis through angiotensin IPs role as a vasoconstrictor. Defects in the renin angiotensin system can lead to hypertension, heart attack, and stroke (Weir, 1999). Studies have shown an inverse relationship between Vitamin D3 and blood pressure (Li et al., 2002). While studies have been performed on vitamin D's effect on renin expression, little is known about vitamin D's effect on the angiotensin II high-affinity type 1 (ATi) receptor. The hypothesis for this study was that human iliac artery endothelial cells (HIAEC) supplemented with 1,25-dihydroxy vitamin D3 will express less AT] receptor …

Single -Walled Carbon Nanotubes Separation And Redox Chemistry And Their Applications For Optical Biosensing And Scaffold Materials, Xiaomin Tu

Theses and Dissertations

Single-walled carbon nanotubes (SWNTs) have drawn great attention worldwide for their unique electronic, mechanical and optical properties. This dissertation details studies of some of the most important areas including: (1) Single-stranded DNA (ssDNA) assisted separation of SWNTs using high performance liquid chromatography; (2) Optical sensitivity and kinetic studies of redox reaction of ssDNA functionalized SWNTs with hydrogen peroxide (H 2 O 2 ); (3) Effects of Ag + on the redox reaction of ssDNA-encased SWNTs with hydrogen peroxide; (4) Single-walled carbon nanotube based optical sensors for DNA detection; and (5) SWNTs as scaffolds for promoting stem cell differentiation into bone …

Teacher Motivation In Arkansas Schools, Tamekia Love Brown

Theses and Dissertations

This study compared perceptions of teacher intrinsic and extrinsic motivation, dependent variables, among the independent variables of job type (teachers and administrators), years of experience (novice, experienced, and veteran), and gender. Teachers, N = 793, indicated their level of agreement with the motivation statements and 90 administrators indicated what they believe motivates teachers. Due to a low correlation between the dependent variables and small cell sizes for the novice administrators; researcher conducted univariate, rather than multivariate analyses, using a Bonferroni adjusted alpha of .017. Two independent t -tests compared teacher and administrator responses to the scales. Results indicated that teacher …

Off-The-Record Secure Chat Room Via Public Im Services, Jiang Bian

Theses and Dissertations

This thesis proposes a solution into the implementation of on-line chat-room environments that ensures the privacy protection of such services and provides an off-the-record feature. Instant Messaging (IM) is becoming an integral part of social as well as business life. The main concern with IM systems is that the information being transmitted is easily accessible. Some protection could be achieved with the use of a secure tunneling (i.e. VPN etc.). Nevertheless, even the use of VPN-like technologies does not provide end-to-end secrecy. Off-the-record (OTR), designed by Borisov. N et al. is a protocol which enables IM users to have private …

Sociocultural Strain Theory, Amy L. Proctor

Theses and Dissertations

In reaction to criticisms of existing strain theories, Agnew (1992) developed General Strain Theory, and in doing so moved toward micro-level conceptions of strain. A return to the cultural concepts found in traditional strain theories may provide a more complete examination of delinquency/criminality, as it would incorporate the influence that culture has on rates of delinquency/criminality among certain groups in American society. This thesis adds to the knowledge base of criminological thought through the creation of a new strain theory. Sociocultural Strain Theory (SST) may provide a better explanation of delinquency/criminality, particularly among racial/ethnic minorities, by taking into consideration cultural …

Techniques For Reclaiming Mined Lands With Native Plants, Maria Elena Melnechuk

Theses and Dissertations

In this experiment I examined the role of mycorrhizae, seeding rate, and fertilizer in promoting growth of native plants at a reclaimed mine site in central Arkansas. Permanent field plots were established to examine effects of treatments on native plant cover, nonnative plant cover, and bare ground. By the final year of data collection, 18 native species had been newly established at the experimental site. Compared to plots without mycorrhizae, plots with mycorrhizae had significantly higher native plant cover in the first sampling year only. The addition of native seed was important—plots without added seed had significantly lower native plant …

Electronic Media And The Novice-Level Esl Textbook, Jacob Selz Brown

Theses and Dissertations

The past decade had seen a re-evaluation in both foreign language, and English as a Second/Foreign Language, instruction methods due to the new technology available to aide in this instruction. While different institutions have access to different levels of technology, the adoption of basic technology for the classroom will eventually happen in the entire developed world. The purpose of this thesis is to wed the new technology available to a traditional textbook. It offers guided instruction to help a facilitator who may have never taught English as a Second/Foreign Language before, along with the actual electronic media needed to supplement …

Electrochemical Studies Of Some Furyl, Indol, Pyrrol, Hydroxynapthyl And Thienyl Derived Sulfonamides And Their Antibacterial Activities, Raja S. Machana

Theses and Dissertations

Sulfonamides are synthetic, wide-spectrum, antibiotics that find current therapeutic applications in the treatment of urinary tract infections, nocardiosis, and toxoplasmosis. Rapid development of bacterial resistance to this class of antimicrobial agents has obligated the need for synthesis of new sulfonamide derivatives. N 1 substitution with heterocyclic moieties produced variable antibacterial efficacies and their structure activity relationships were fairly established. However, para-amino (the N of which is designated as N 4 ) sulfonamide derivatives are less commonly studied. In this research we have selected a series of para-amino sulfonamide derivatives. Since redox potentials are important in determining the physiological activity of …

Spatial And Temporal Patterns Of Anadromous Fish Passage At Boshers Dam Vertical Slot Fishway On The James River, Richmond, Virginia, Matthew Thomas Fisher

Theses and Dissertations

Boshers dam vertical slot fishway, James River, Virginia, U.S.A., opened in 1999 and restored connectivity to 543.3 km of spawning habitat for anadromous fish. The fishway also allowed local movement of resident species. Video observation from 2001-2005 was used to evaluate environmental predictors of American shad (Alosa sapidissima) and sea lamprey (Petromyzon marinus) passage. The ecological effects of restoring connectivity to upstream habitat for gizzard shad (Dorosoma cepedianum) and blue catfish (Ictalurus furcatus) are also discussed. Regression analysis determined that the best predictor of increased daytime American shad passage is higher water temperatures and discharge and for increased daytime sea …

Developing A Rapid Method For Assessing The Physical Stability Of Streams In Minnesota's Agassiz Beach Ridges, Abigail V. Franklund

Theses and Dissertations

This thesis assessed the physical characteristics and stability of selected western Minnesota streams that cross the eastern beach ridges of glacial Lake Agassiz. Stream and river channels in this area host unusually diverse aquatic habitat and biodiversity, but incompatible land use along channels and in watersheds impair their quality and function. Previous rapid assessment protocols have been developed for stream attributes and stability, but these methods have been developed elsewhere in the United States and are not necessarily appropriate for western Minnesota’s unique geology and landscape.

A rapid reconnaissance method was developed to assess stream conditions using an integrated numerical …

Role Of Ceramide-1-Phosphate As A Specific And Potent Activator Of Group Iva Cytosolic Phospholipase A2 Alpha, Preeti Subramanian

Theses and Dissertations

Eicosanoids are potent mediators of inflammatory response whose role has been well established in inflammatory disorders. Release of arachidonic acid by group IVA cytosolic phospholipase A2 α (cPLA2α) is the initial rate limiting step for the production of eicosonoids in response to inflammatory mediators. Previous findings from our laboratory have demonstrated that cPLA2α is directly activated by the emerging bioactive sphingolipid, ceramide-1-phosphate (C1P). In this study, we have developed a modified Triton X-100/phosphatidylcholine (PC) mixed micelle assay which was utilized to determine the kinetics and specificity of this lipid-enzyme interaction. Using this assay, the activity of the enzyme increased in …

Evaluating The Psychosocial Effects Of Two Interventions, Tai Chi And Spiritual Growth Groups, In Women With Breast Cancer, Sarah M. Rausch

Theses and Dissertations

One in seven women will develop breast cancer. Most will suffer medically and psychologically from the disease. Complementary and alternative medicine (CAM) interventions such as tai chi and spiritual growth groups have proven to be beneficial for this population, however, many questions remain regarding the mechanisms of action in these techniques. The purpose of this study was to evaluate the psychosocial effects and mechanisms of two 10-week interventions (tai chi and spiritual growth groups) within the context of a larger randomized, controlled NCI-funded study (R01 CA114718, Nancy McCain, PI) in women recently diagnosed with breast cancer. The present study evaluated …

Overbite Correction And Smile Esthetics, Kevin Erick Kelleher

Theses and Dissertations

The purpose of this prospective clinical study was to investigate differences in outcomes from two common treatment modalities used to reduce deep overbite: maxillary incisor intrusion using an intrusion arch and posterior tooth eruption using an anterior bite plate. Pre-treatment, post-overbite correction and post-treatment records were gathered from 32 patients who presented with deep overbite malocclusions to the Virginia Commonwealth University orthodontic clinic. Both groups of patients experienced reductions in overbite and maxillary incisor display as well as maxillary and mandibular incisor proclination and mandibular incisor occlusal movement during treatment. In the intrusion arch group, the center of resistance of …

Novel Sulfated 4-Hydroxycinnamic Acid Oligomers As Potent Anticoagulants, Brian Lawrence Henry

Theses and Dissertations

The occurrence of thrombosis in several pathophysiological conditions creates a huge need for anticoagulation therapy. Thrombin and factor Xa have been prime targets for regulation of clotting through the direct and indirect mechanism of inhibition. This work investigates chemo-enzymatically prepared oligomers of 4-hydroxycinnamic acids (DHPs) as potential anticoagulants. Oligomers were prepared through peroxidase-catalyzed oxidative coupling of 4-hydroxycinnamic acids. The products resulting from this reaction are called CDs, FDs and SDs. Structurally, these sulfated DHPs are unique and do not resemble any of the anticoagulants known in the literature.DHP oligomers were found to increase clotting times at concentrations comparable to heparin. …

Effects Of Cxcl8 Overexpression On Tumor Cell Proliferation And Migration In An Hnscc Cell Model, Emil Paul Christofakis

Theses and Dissertations

Head and neck squamous cell carcinoma is the 6th most common malignancyworldwide. Recently, a link between cancer and inflammation has been found. Mediatingthis relationship are the chemotactic cytokines known as chemokines. CXCL8 (Interleukin-8), a CXC ELR+ Chemokine mainly responsible for neutrophil chemoattraction, has beenimplicated in increased tumor proliferation, migration and angiogenesis. The current studytests the effects of CXCL8 on the tumor proliferation and metastasis. By genetically modifying cells to knockdown or overexpress the CXCL8 gene we tested its biological rolein head and neck cancer progression. Overexpression of CXCL8 in HN4 tumor cells withlow endogenous CXCL8 levels was found to increase …

The Effect Of A Nominal Fee On Treatment Choices For Children Needing Dental Rehabilitation, D'Audra M. Cole

Theses and Dissertations

Objective: The purpose of the study was to determine if a co-payment resulted in a differential preference for general anesthesia (GA) or oral sedation (OS) and, if so, to examine whether age, the number of appointments, perceived risks of treatment, child's awareness during treatment, or insurance type appeared to play a role in this preference.Methods: Using a cross-sectional survey design, questionnaires were distributed to caregivers of patients in the waiting room of the Virginia Commonwealth University Pediatric Dental Clinic. Two different questionnaires were distributed randomly. Both surveys described a scenario with the need for dental treatment under general anesthesia (GA) …

The Quantitative Genetics Of Neurodevelopment: A Magnetic Resonance Imaging Study Of Childhood And Adolescence, James Eric Schmitt

Theses and Dissertations

Understanding the causes of individual differences in brain structure may give clues about the etiology of cognition, personality, and psychopathology, and also may identify endophenotypes for molecular genetic studies on brain development. We performed a comprehensive statistical genetic study of anatomic neuroimaging data from a large pediatric sample (N=600+) of twins and family members from the Child Psychiatry Branch at the NIMH. These analyses included variance decomposition of structural volumetric endophenotypes at several levels of resolution, voxel-level analysis of cortical thickness, assessment of gene by age interaction, several multivariate genetic analyses, and a search for genetically-mediated brain-behavioral relationships. These analyses …

Corticular Photosynthetic Dynamics For A Coastal Evergreen Shrub: Myrica Cerifera, Jaclyn K. Vick

Theses and Dissertations

I quantified seasonal variations in corticular photosynthesis in 1st through 5th order branches of Myrica cerifera L. (Myricaceae) in order to determine whether corticular photosynthesis contributes to whole plant carbon gain by reducing respirational CO2 loss. Maximum % refixation was 110 ± 39 % of CO2 efflux in the dark (Rd) in 1st order branches during winter, minimum was 18 ± 3 % in 5th order branches during summer. Variations in % refixation paralleled changes in photosynthetically active radiation (PAR). As light attenuated with increasing branch order % refixation decreased. Increased PAR in the winter due to a more sparse …

Drift Tube Ion Mobility Measurements For Thermochemistry, Kinetics And Polymerization Of Cluster Ions, Ridha Ben Mohsen Mabrouki

Theses and Dissertations

In this work, the Drift Tube Ion Mobility technique is used to study the hydrophobic hydration and solvation of organic ions and measure the thermochemistry and kinetics of ion-molecule reactions. Furthermore, an exploratory study of the intracluster polymerization of isoprene will be presented and discussed. The ion hydration study is focused on the C3H3+ cation1 and Pyridine▪+ radical cation.2 The chemistry of the cyclic C3H3+ cation1 has received considerable attention and continues to be an active area of research.3-7 The binding energies of the first 5 H2O molecules to c-C3H3+ were determined by equilibrium measurements. The measured binding energies of …

Genetic Variations In Interferon-Induced Genes And Hcv Recurrence After Liver Transplantation, Benjamin Cameron Whitehill

Theses and Dissertations

Hepatitis C Virus (HCV) infection represents a worldwide pandemic and is currently the leading cause of cirrhosis and liver transplantation. After transplantation recurrence is almost universal with 96% of patients testing positive for viral RNA and exhibiting histological evidence of infection within the first year. Type I interferons (IFN) and interferon inducible genes are responsible for the innate antiviral state and single nucleotide polymorphisms (SNPs) within these genes may affect the patients ability to respond post-transplantation. We hypothesize the elucidation of associations between SNPs in Type-I Interferon and Interferon inducible genes and HCV recurrence post-liver transplantation might help to identify …