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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 …

Vocal And Instrumental Musicians: Electrophysiologic And Psychoacoustic Analysis Of Pitch Discrimination And Production, Dee Adams Nikjeh

USF Tampa Graduate Theses and Dissertations

Neurological evidence indicates that instrumental musicians experience changes in the auditory system following skill acquisition and sensory training; yet, little is known about auditory neural plasticity in formally trained vocal musicians. Furthermore, auditory pitch discrimination and laryngeal control are recognized as essential skills for vocal musicians; however, the relationship between physiological variables, perceptual abilities, and vocal production is unclear. Electrophysiologic and psychoacoustic measures were used to examine pitch production accuracy as well as pre-attentive and active pitch discrimination between nonmusicians and two classes of musicians. Participants included 40 formally trained musicians (19 vocalists/21 instrumentalists) and 21 nonmusician controls. All were …

Thermal Analyses Of Hydrophilic Polymers Used In Nanocomposites And Biocompatible Coatings, Kadine Mohomed

USF Tampa Graduate Theses and Dissertations

ABSRACT: This research focuses on two hydrophilic polymers that form hydrogels when they sorb water: Poly(2-hydroxyethyl methacrylate) (PHEMA) and Poly(2,3-dihydroxypropyl methacrylate) (PDHPMA). Present work in the field obviated the need to properly characterize the thermal and dielectric properties of these materials.The dielectric permittivity, e', and the loss factor, e", of dry poly(2-hydroxyethyl methacrylate) and poly(2,3-dihydroxypropyl methacrylate) were measured using a dielectric analyzer in the frequency range of 0.1Hz to 100 kHz and between the temperature range of -150 °C to 275°C. The dielectric response of the sub-Tg gamma transition of PHEMA has been widely studied before but little to no …

Investigating The Fouling Behavior Of Reverse Osmosis Membranes Under Different Operating Conditions, Dhananjaya P. Niriella

USF Tampa Graduate Theses and Dissertations

This dissertation describes the investigation of the fouling of a reverse osmosis membrane under different operating conditions. A mass transfer model to predict the permeate flux decline is defined. These studies used kaolin clay and bentonite clay as the fouling particles. As the membranes, thin film Low fouling Composite 1 polyamide reverse osmosis flat sheet membranes were used. Baseline experiments using only kaolin in D.I. water were conducted. At an operating pressure of approximately 1,380 kPa, no flux decline was observed. These results established the effects of a membrane-particle interaction. For the fouling experiments with kaolin clay, experiments show a …

Coral Reef Habitat Change And Water Clarity Assessment (1984-2002) For The Florida Keys National Marine Sanctuary Using Landsat Satellite Data, David A. Palandro

USF Tampa Graduate Theses and Dissertations

The decline of coral reef habitats has been witnessed on a global scale, with some of the most dramatic decline occurring in the florida keys. as remote sensing can provide a synoptic view of coral reef ecosystems, 28 landsat images (1984-2002) were utilized to study water clarity and habitat change. first, the data were used to derive the diffuse attenuation coefficient (kd, m-1), a measure of water clarity, for 29 sites throughout the florida keys national marine sanctuary (fknms). landsat-derived kd values from bands 1 (blue) and 2 (green) provided useful information for 26 of 29 sites, whereas band 3 …

Distribution And Habitat Characterization Of The Florida Burrowing Owl In Non-Urban Areas, Mark S. Mueller

USF Tampa Graduate Theses and Dissertations

The full geographic distribution and habitat use of the Florida Burrowing Owl, a state "Species of Special Concern," is not well-understood, particularly in remote, non-urban areas. This thesis aimed to expand and improve knowledge about non-urban burrowing owls. We first compiled databases of historic sighting observations. Fieldwork verified and updated existing breeding observation point records and also yielded new breeding locations. Using a GIS, we characterized observed land use, landcover, relevant soil attributes, projected future land use and managed area status for selected points. We quantified landcover within biologically-determined buffer distances around burrows from our own field-verified records. Using standard …

Altered Features Of Female Pigeons (Columba Livia) Elicit Preference Behavior In Male Pigeons, Tadd B. Patton

USF Tampa Graduate Theses and Dissertations

Previous research has shown that male pigeons (Columba livia) respond with courtship displays to video playbacks of a female pigeon indicating that they 'recognize' the female as a potential mate. Courtship displays significantly decline when the head region of the female is occluded (Shimizu, 1998) suggesting that features located within the head are important for species recognition and mate selection. However, little is known about the exact visual features necessary to elicit displays. The current study examined the preference behavior of male pigeons when given a choice between photographic images of normal looking or altered female pigeon faces. The altered-face …

The Acquisition Of Spanish Through Videoconferencing And Video-Based Lessons By Individual Fifth Graders, Annette L. Norwood

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to provide an in-depth examination of the language learning experiences of four fifth-grade students learning Spanish through videoconferencing and video-based lessons. This interpretive qualitative study involved intensive data collection over a period of 7 months through participant observation, audio and video recording of classes with subsequent transcription, and interviews of the students and their teachers. The following points of focus guided this research: (a) What instances of interaction and output are observed in the different instructional settings?; (b) Are patterns of change observed in learners' language production during the period under study?; (c) What …

Late Holocene Planktic Foraminiferal Assemblages From Orca Basin; Effects Of Dissolution On Faunal Assemblages, Denise D. Palmer

USF Tampa Graduate Theses and Dissertations

Studies of planktic foraminifers have been, and continue to be, very important to paleoceanographic reconstructions and are dependent on the integrity of the carbonate tests. This study investigates the methods and procedures that can be used to obtain an accurate planktic foraminifer assemblage. Samples from Orca Basin boxcore OB-BC4D were processed and examined to obtain census data on planktic foraminifers. Experimentation of the splitting technique demonstrates the method is acceptable for estimating a planktic foraminifer assemblage. The effects of a sonication step in the processing of the faunal assemblage were also examined and revealed that sonication is not recommended for …

The Science And Policy That Compels The Wetland Mitigation Of Phosphate-Mined Lands, Nejma Danielle Piagentini

USF Tampa Graduate Theses and Dissertations

The State of Florida ranks fifth in the world's production of phosphate. The phosphate industry relies on surface mining to withdraw the phosphate ore, and this process can devastate the natural environment. One of the most impacted natural resources is wetlands. Federal laws permit the legal destruction of wetlands providing their loss is compensated by the mitigation (i.e., the restoration, creation, or enhancement) of other wetlands, but the complexity of wetland ecosystems makes the mitigation process difficult. One of the goals of this thesis is to review the established Federal, State and non-regulatory guidelines for the development and maintenance of …

The Contribution Of The Neighborhood Context To Social Disparities In Access To Health Care Among Sexually Experienced Adolescent Females, Jodi Nearns

USF Tampa Graduate Theses and Dissertations

Access to health care is an important resource for sexually experienced adolescent females in the prevention of unintended pregnancy and sexually transmitted infections, including HIV. However, a paucity of research exists regarding the extent to which social disparities in access to health care exist among this vulnerable population of adolescents, including the potential contribution of the neighborhood context. Therefore, the primary aims of this dissertation were to examine (1) the extent to which racial and socioeconomic disparities in access to health care exist among sexually experienced adolescent females, (2) the extent to which access to health care among sexually experienced …