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Tyrosinase-Like Activity Of Several Alzheimer’S Disease Related And Model Peptides And Their Inhibition By Natural Antioxidants, Kashmir Singh Juneja

USF Tampa Graduate Theses and Dissertations

Neurodegenerative diseases are associated with loss of neurons ultimately leading to a decline in brain function. Alzheimer's disease (AD) is considered one of the most common neurodegenerative disorders that affects 16 million people worldwide. The cause of the disease remains unknown, although significant evidence proposes the amyloid Beta-peptide (A-Beta) as a potential culprit. The binding of Cu2+ by the soluble fragments of A-Beta have shown to form Type-3 copper centers and catalyze the oxidation of catechol-containing neurotransmitters. Furthermore, the use of flavonoids as antioxidants to slow or inhibit the neurotransmitter oxidation has suggested further health benefits with their consumption. A …

A New Approach To Kainoids: Total Syntheses Of (-)-Kainic Acid And (+)-Allokainic Acid, Young Chun Jung

USF Tampa Graduate Theses and Dissertations

(-)-Kainic acid and its C-4 epimer, (+)-allokainic acid are parent members of a class of substituted pyrrolidines known as kainoids. They have been found to exhibit powerful biological properties, principally neuroexcitatory. Kainic acid has become especially important in the study of Alzheimer's disease, epilepsy, and other neurological disorders. The total syntheses of (-)-kainic acid and (+)-allokainic acid were achieved using (L)-glutamic acid as the starting material and the sole source of stereochemical induction. The key steps for these successful syntheses involve formation of the gamma-lactam core via rhodium (II) catalyzed intramolecular C-H insertion of the alpha-diazo-alpha-(phenylsulfonyl)acetamide intermediate and the stereoselective …

Differential Coupling Of Rgs3s And Rgs4 To Gpcr-Girk Channel Signaling Complexes, Cristina Jaén

USF Tampa Graduate Theses and Dissertations

'Regulators of G protein signaling' (RGS proteins) modulate the G proteincycle by enhancing the GTPase activity of Ga subunits. These changesaccelerate the kinetics of ion channel modulation by Gai/o-coupled receptors(GPCRs) such as the G protein-gated inward rectifier K+ (GIRK/Kir3) channel. Myexperiments indicate that a single cerebellar granule (CG) neuron, a cell type thatendogenously expresses GIRK channels is able to express a wide variety ofRGS proteins. I selected two of them, which are widely expressed andtranscriptionally regulated during pathophysiologic conditions, to compare theirfunctional properties. I originally described the differential modulatory effects oftwo RGS proteins, the RGS3 short isoform (RGS3s) and RGS4, …

Practical Applications Of Molecular Dynamics Techniques And Time Correlation Function Theories, Christina Ridley Kasprzyk

USF Tampa Graduate Theses and Dissertations

The original research outlined in this dissertation involves the use of novel theoretical and computational methods in the calculation of molecular volume changes and non-linear spectroscopic signals, specifically two-dimensional infrared (2D-IR) spectroscopy. These techniques were designed and implemented to be computationally affordable, while still providing a reliable picture of the phenomena of interest. The computational results presented demonstrate the potential of these methods to accurately describe chemically interesting systems on a molecular level. Extended system isobaric-isothermal (NPT) molecular dynamics techniques were employed to calculate the thermodynamic volumes of several simple model systems, as well as the volume change associated with …

Investigations Of Fiber Optic Temperature Sensors Based On Yb:Y3Al5O12, Jermaine L. Kennedy

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of temperature sensors which employ a fiber-optic probe consisting of single crystal YB3BAlB5BOB12B (YAG) fiber with a phosphor of short length grown directly onto one end using the laser heated pedestal growth method. The response of all the crystalline temperature sensors derives from the temperature-dependent decay time of fluorescence. Yb3+P ions served as the fluorescer, while the addition of various rare-earth codopants (i.e., NdP3+ and ErP3+) with YbP3+ provided an additional path in the form of phonon assisted energy transfer. With the additional nonradiative decay path, the temperature sensors exhibited a more desirable response. A …

Predictors And Outcomes Of Hospice Use Among Medicare And Medicaid Dual-Eligible Nursing Home Residents In Florida: A Comparison Of Non-Hispanic Blacks And Non-Hispanic Whites, Jung, Kwak

USF Tampa Graduate Theses and Dissertations

This research investigated the racial/ethnic differences in hospice utilization and the effect of hospice in reducing the risk of hospital death at the end of life among non-Hispanic Black and non-Hispanic White dual-eligible (Medicare and Medicaid) older adults residing in a nursing home setting. The final study population included 30,765 non-Hispanic Black and non-Hispanic White nursing home residents who died between state fiscal years 2000-2002 in Florida.The behavioral model of health services use successfully predicted group membership in hospice use. In the full model, seven variables - female gender, non-Hispanic White race/ethnicity, being married, urban area of residence, and cancer …

Structured Light For Three-Dimensional Microscopy, Leo G. Krzewina

USF Tampa Graduate Theses and Dissertations

The conventional light microscope is an indispensable tool for many physical and life science applications, but is of limited usefulness for three-dimensional imaging due to its increasingly narrow depth of field at high magnifications. Focused regions may be obscured by defocused neighbors or noise from extraneous light sources and subsurface scattering. By rejecting light originating from outside the depth of focus it is possible to minimize these problems. When a contiguous series of such focused slices, or optical sections, are obtained along an axis of an extended object they may be combined to form a complete, focused three-dimensional surface image. …

Occupancy And Function Of The Hepatic Hmg-Coa Reductase Promoter, William Raymond Lagor

USF Tampa Graduate Theses and Dissertations

HMG-CoA reductase (HMGR) catalyzes the rate controlling step in cholesterol production. This enzyme is highly expressed in the liver where it is subject to extensive hormonal and dietary regulation. This study was undertaken to examine the occupancy and function of the hepatic HMGR promoter in regards to insulin and sterol regulation. HMGR protein and mRNA are substantially decreased in diabetic animals and rapidly restored by administration of insulin. Nuclear run-on assays revealed that HMGR transcription was substantially reduced in the diabetic rats, and fully restored within two hours after insulin treatment. In vivo footprinting revealed several areas of protein binding …

N-Thiolated Β-Lactam Antibiotics: Synthesis And Structure-Activity Studies Of C3- Oxygenated Derivatives And Attachment To New, Functionalized Caprolactone Monomers And Polymers, J Michelle Leslie

USF Tampa Graduate Theses and Dissertations

N-Thiolated beta-lactams are a new class of anti-MRSA and anti-Bacillus agents that have recently been reported by our laboratories. From previous studies performed in our laboratories, it is believed that the N-thiolated beta-lactams exert their antimicrobial activity through a unique mode of action that is completely unlike that of classical beta-lactam antibiotics. In the first chapter of this dissertation, a review of previously prepared N-thiolated beta-lactam analogues and their mode of action is presented. In the second chapter, the synthesis of seven different C3-oxygenated derivatives is described. These analogues were tested for antibacterial activity against Staphylococcus aureus, nine different strains …

Electrically Charged Sol-Gel Coatings For On-Line Preconcentration And Analysis Of Zwitterionic Biomolecules By Capillary Electrophoresis, Wen Li

USF Tampa Graduate Theses and Dissertations

Novel on-line methods are presented for the extraction, preconcentration and analysis of zwitterionic biomolecules using sol-gel-coated columns coupled to a conventional UV/visible detector. The presented approaches do not require any additional modification of the commercially available standard CE instrument. Extraction, stacking, and focusing techniques were used in the preconcentration procedures. The positively charged sol-gel coatings were created using N-octadecyldimethyl[3-(trimethoxysilyl) proply]ammonium chloride (C18-TMS) in the coating sol solutions. Due to the presence of a positively charged quaternary ammonium moiety in C18-TMS, the resulting sol-gel coating carried a positive charge. The negatively charged sol-gel coatings were due to the presence of sulfonate …

Saharan Dust And Phosphatic Fidelity: A Three Dimensional Biogeochemical Model Of Trichodesmium On The West Florida Shelf, Jason M. Lenes

USF Tampa Graduate Theses and Dissertations

The availability of iron within the surface waters of the broad, oligotrophic West Florida shelf (WFS) controls periodic blooms of the pelagic marine cyanobacterium Trichodesmium. Summer delivery of iron (Fe), in the form of Saharan dust, alleviates this growth constraint, shifting limitation to the efficiency of phosphorus (P) cycles. Florida's rivers drain Miocene phosphorus deposits to supply the WFS with freshwater nutrient supplies at molar dissolved inorganic nitrogen/phosphate (DIN/PO4) ratios of less than 6. These diazotrophs draw upon ubiquitous stocks of dissolved nitrogen gas, once stimulated by Fe-deposition within P-replete waters of the West Florida shelf. An extensive in situ …

Cannabinoids Suppress Dendritic Cell-Induced T Helper Cell Polarization, Tangying (Lily) Lu

USF Tampa Graduate Theses and Dissertations

Cannabinoids suppress Th1 immunity in a variety of models including infection with the intracellular pathogen Legionella pneumophila (Lp). To examine the cellular mechanism of this effect, mouse bone marrow-derived dendritic cells (DCs) were studied following infection and drug treatment. DCs produced high levels of IL-12p40 following Lp infection. THC suppressed this cytokine response in a concentration-dependent manner and the endocannabinoids 2-arachidonoyolglycerol and virodhamine less potently suppressed cytokine production. DCs expressed mRNA for cannabinoid receptor 1 (CB1), CB2, and transient receptor potential vanilloid type 1 (TRPV1); furthermore, inhibition of Gi signaling by adding pertussis toxin completely attenuated the suppression induced by …

Control Of Lysogeny In Marine Bacteria: Studies With Φhsic And Natural Populations, Amy K. Long

USF Tampa Graduate Theses and Dissertations

Viruses have an estimated global population size of 10 to the 31st, with a significant proportion found in the marine environment. Viral lysis of bacteria affects the flow of carbon in the marine microbial food web, but the effects of lysogeny on marine microbial ecology are largely unknown. In this thesis, factors that influence the control of lysogeny were studied in both the phiHSIC/Listonella pelagia phage-host system and in bacterioplankton populations in the Gulf of Mexico. Using macroarrays dotted with phiHSIC amplicons, viral gene expression over the course of a synchronous infection experiment was measured. Early, middle, late, and continually …

Copper And Iron Complexes Of Linear And Crosslinked Polymers As Catalysts For Phosphoester Hydrolysis And Oxidative Transformation Of Phenolic And Catecholic Substrates, Vasiliki Lykourinou

USF Tampa Graduate Theses and Dissertations

The goal of this study is to utilize polymers as macromolecular ligands for the construction of catalysts by formation of coordination complexes with transition metals with the main focus on complexes of Cu(II) and Fe(III) and further determine (a) their catalytic efficiency (b) mechanism of action (c) similarities to enzymatic systems and synthetic metal complexes. The reactions of interest are (1) hydrolytic cleavage of a series of phosphoesters(2) oxidation of catechol type of substrates (3) hydroxylation of phenolic substrates and chlorinated phenols (4) activation of molecular oxygen and/ or hydrogen peroxide (5)oxidative cleavage of DNA plasmid.

The major premise of …

Gender Differences During Heat Strain At Critical Wbgt, Christina L. Luecke

USF Tampa Graduate Theses and Dissertations

Heat stress is influenced by environmental conditions, workload and clothing. A critical environment is the upper limit of compensable heat stress for a given metabolic rate and clothing ensemble. The physiological strains associated with heat stress are core and skin temperatures, heart rate and physiological strain index (PSI). Because heat dissipation mechanisms may differ between men and women, there may be gender differences in the critical environment and the associated physiological variables. Gender differences were explored between acclimated men (n = 20) and women (n = 9) at the upper limit of compensable heat stress. Participants walked on a motorized …

Virginia Woolf And The Persistent Question Of Class: The Protean Nature Of Class And Self, Mary C. Madden

USF Tampa Graduate Theses and Dissertations

From the beginning of her career, Virginia Woolf moves beyond the perspective of her inherited class position to challenge a damaging class system. She increasingly recognizes the extent of her own complicity in the creation and maintenance of class structures supporting patriarchy, war, and British imperialism. Highlighting ambiguities inherent in the very category of class, she acknowledges the limiting "boxes" of language itself in attempts to rethink class. For Woolf, class is not monolithic but internally differentiated by gender and race. Examining Woolf's early work in relation to class theory shows that throughout her career Woolf interrogates the imbrication of …

Quantitative Biological Microscopy By Digital Holography, Christopher J. Mann

USF Tampa Graduate Theses and Dissertations

In this dissertation, improved techniques in digital holography, that have produced high-resolution, high-fidelity images, are discussed. In particular, the angular spectrum method of calculating holographic optical field is noted to have several advantages over the more commonly used Fresnel transformation or Huygens convolution method. It is observed that spurious noise and interference components can be tightly controlled through the analysis and filtering of the angular spectrum. In the angular spectrum method, the reconstruction distance does not have a lower limit, and the off-axis angle between the object and reference waves can be lower than that of the Fresnel requirement, while …

Breathing Easier: Ethnographic Study Of Acute Respiratory Infection In Children In Rural Ecuador, John S. Luque

USF Tampa Graduate Theses and Dissertations

This dissertation research utilizes anthropological methods to determine the degree to which the signs and symptoms female caregivers identify as causes of acute respiratory infections (ARIs) in under-fives in rural Ecuador correspond with Western biomedical categories. By employing both a semi-structured medical history questionnaire and more open-ended ethnographic methods such as in-depth informant interviews and focus group research, the researcher identifies the factors which determine timely health care-seeking behaviors of female caregivers in this case study. Economic factors such as the cost of medications and lost work hours were determined to be the primary financial obstacles for timely health care-seeking. …

Electrogenetherapy Of Established B16 Murine Melanoma By Using An Expression Plasmid For Hiv-1 Viral Protein R, Andrea Nicole Mccray

USF Tampa Graduate Theses and Dissertations

Novel therapies and delivery methods directed against malignancies such as melanoma, and particularly metastatic melanoma, are needed. The HIV-1 accessory protein Vpr (viral protein R) has previously been demonstrated to induce G2 cell cycle arrest as well as in vitro growth inhibition/killing of numerous tumor cell lines. In vivo electroporation has been utilized as an effective delivery method for pharmacologic agents as well as DNA plasmids that express "therapeutic" proteins and has been targeted to various tissues including malignant tumors. In this study, we assessed the ability of electroporation-mediated delivery of Vpr plasmid (pVpr) to induce growth attenuation or complete …

Patterns And Dynamics Of Ocean Circulation Variability On The West Florida Shelf, Yonggang Liu

USF Tampa Graduate Theses and Dissertations

Patterns of variability and the dynamics of the ocean circulation on the West Florida Shelf (WFS) are investigated using multi-year, shelf-wide oceanographic observations from moored Acoustic Doppler Current Profiler (ADCP) arrays,hydrographic cruises, High-Frequency (HF) radars, satellites, and coastal tide gauges.Novel neural network techniques, Self-Organizing Map (SOM) and Growing Hierarchical Self-Organizing Maps (GHSOM), are introduced as feature extraction methods in physical oceanography. The SOM is demystified and demonstrated to be a useful feature extraction method in a series of performance evaluations using artificial data sets comprising known patterns. It is then applied to velocity time series from moored ADCP arrays and …

Investigation Of The Effects Of Increased Levels Of O-Glcnac Protein Modification On Protein Kinase C And Akt, Jason Aaron Matthews

USF Tampa Graduate Theses and Dissertations

O-linked N-acetylglucosamine (O-GlcNAc) is an abundant and ubiquitous post-translational modification that has been shown to play a role in regulating a variety of intracellular processes. The pathway responsible for generating the O-GlcNAc modification, the hexosamine biosynthetic pathway (HBP), has also been shown to affect the activity and translocation of certain protein kinase C (PKC) isoforms. To investigate if the effects of HBP flux on PKC translocation observed by others is related to the O-GlcNAc modification, O-GlcNAc levels in human astroglial cells were elevated using four separate O-GlcNAc modulating agents followed by analysis of cytosol and membrane concentrations of PKC-epsilon, -alpha, …

The Role Of Social Structural And Social Contextual Factors In Shaping Chronic Disease And Chronic Disease Risk Behavior: A Multilevel Study Of Hypertension, General Health Status, And Mental Distress, Caroline Mae Mckay

USF Tampa Graduate Theses and Dissertations

At present there is a reliance on behavioral interventions that have been limited in their effectiveness to reduce the public health burden of chronic disease, partly because the effects of social context on the initiation and maintenance of health behaviors is not incorporated into public health policy and practice. Yet current research indicates that there are macro-level structural and contextual influences on population health that cannot be reduced to individual or compositional effects. This study investigated the associations between social structural factors, community social context, individual characteristics, and self-reported correlates of disease. Distal influences included social structural inequalities such as …

Crystal Engineering Of Novel Pharmaceutical Forms, Jennifer Anne Mcmahon

USF Tampa Graduate Theses and Dissertations

In the context of pharmaceutical development, it is abundantly clear that there is a need for greater understanding and control of crystalline phases. The field of crystal engineering is poised to address such issues and has matured into a paradigm for the supramolecular synthesis of new compounds with desired properties. Crystal structures are unpredictable by nature, however, the interactions that lead to crystal formation are becoming much more predictable. By means of model compound studies, the delineation of the hierarchy of hydrogen bonding between complementary functional groups or supramolecular heterosynthons can be accomplished. Competitive co-crystallization studies along with data extracted …

Cross-Dressing In Sarah Grand's The Tenor And The Boy And E.D.E.N Southworth's The Hidden Hand: Gender, Class, And Power, Marcy Wynn Murray

USF Tampa Graduate Theses and Dissertations

This thesis concerns female cross-dressing in nineteenth-century literature and the ways in which these images challenge gender and class hierarchies. Cross-dressing abounds in nineteenth-century literature, forming a thematic that crosses national boundaries. Therefore, this thesis considers works from both the British and American traditions. The primary texts explored are The Tenor and the Boy (1893) by Sarah Grand and The Hidden Hand, or Capitola the Madcap (1888) by E. D. E. N. Southworth. When published, both of these texts were commercial successes and can therefore be considered representative of popular literature of the time.

The use of transvestite characters allows …

Molecular Simulations Of Pd Based Hydrogen Sensing Materials, Ling Miao

USF Tampa Graduate Theses and Dissertations

Hydrogen sensor technology is a crucial component for safety and many other practical concerns in the hydrogen economy. To achieve a desired sensor performance, proper choice of sensing material is critical, because it directly affects the main features of a sensor, such as response time, sensitivity, and selectivity. Palladium is well-known for its ability to sorb a large amount of hydrogen. Most hydrogen sensors use Pd-based sensing materials. Since hydrogen sensing is based on surface and interfacial interactions between the sensing material and hydrogen molecules, nanomaterials, a group of low dimensional systems with large surface to volume ratio, have become …

Pediatric Healthcare Providers’ Screening Practices: Impact Of Training On Early Identification Of Autism, Aja M. Meyer

USF Tampa Graduate Theses and Dissertations

This study explored the effectiveness of the Autism System of Care (ASC) trainings by measuring change in pediatric healthcare providers' method of identifying young children at-risk for autism spectrum disorders. The majority of participants were pediatricians working in either hospitals or clinics who voluntarily participated in the training. A pretest-posttest nonequivalent-groups design was used in this study. Pre- and post-test questionnaires were used to measure change in participants' screening practices. Due to a small number of participants, most findings from the study were not statistically significant. The small number of healthcare providers who participated in the ASC training was a …

Goal Conflicts, Self-Regulation, And Course Completion: A Comparison Of Web-Based Learners To Traditional Classroom Learners, Barbara Moore

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to examine the goal conflicts, self-regulation, and course completion of post-secondary learners and to compare these factors in distance and traditional learners. Participants completed a self-report survey given on-line to those who had Internet access and administered in paper format to students in traditional classrooms. Procrastination, socializing, and employment were the most common goal conflicts reported by participants. Significantly more web-based students than traditional students were employed and were employed more average hours. Web-based students also had more children under the age of 12 than did traditional students. A significantly greater percentage of web-based …

Developing Culture Conditions To Study Keratocyte Phenotypes In Vitro, Kurt Musselmann

USF Tampa Graduate Theses and Dissertations

The corneal wound healing response involves the activation of keratocytes to proliferate from a quiescent phenotype. The mitogens that cause the initial transformation of the quiescent keratocytes to the active phenotype have not been identified. Even though serum is commonly used to replicate this in vitro, the cornea is avascular and therefore likely not exposed to serum. In the first part of this dissertation, a DMEM/F12 extract of corneal stromas was made and shown to stimulate keratocyte proliferation in both a dose-dependent and cell-density dependent manner. This extract contains mitogens that differ from the mitogens present in serum based on …

Multicultural Education And Cultural Competence In The High Accountability Era: A Study Of Teacher Perception, Jennifer Morley

USF Tampa Graduate Theses and Dissertations

As America's public schools become more diverse, the achievement gap between white students and students of color persists. These gaps are even more apparent in urban areas that serve large numbers of poor students of color. Because the population of aspiring teachers is increasingly white and middle class, theorists and teacher trainers often recommend multicultural education as a solution to working successfully in these schools. Multicultural education theorists claim that their suggestions for K-12 practitioners have not been infused into classrooms and schools, and so maintain that additional training opportunities should be provided for teachers. Although there is ample literature …

Effects Of Translocation On The Florida Burrowing Owl, Athene Cunicularia Floridana, Per Anders Nixon

USF Tampa Graduate Theses and Dissertations

At present, the Florida Burrowing Owl is being threatened by extensive habitat development throughout their small range in the state. Unfortunately, developers are able to collapse burrowing owl burrows during the non-breeding season and flush the owls from an area. In other areas such as Arizona and British Columbia translocation is being utilized to mitigate the effects of development on burrowing owls. In March 2006, the only translocation of burrowing owls in Florida was conducted by Mosaic Phosphate Company. The purpose of this thesis was to elucidate the effects of translocation on Florida burrowing owls. Topics of research include activity …