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2006

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Spring Break: Image, Identity, And Consumer Culture In A Florida Rite Of Passage, Meeghan Kane Jan 2006

Spring Break: Image, Identity, And Consumer Culture In A Florida Rite Of Passage, Meeghan Kane

USF Tampa Graduate Theses and Dissertations

This thesis is a social history of spring break, examining the economic and social aspects of this youth culture phenomenon in Florida. Spring break follows the evolution of youth culture's increasingly complex relationship with an expanding consumer culture. I am exploring its many manifestations in music, film, and popular fiction, but also its rebellious expressions in the riots and arrests on Florida's beaches. I intend to focus on the small beach communities that were transformed by spring break, particularly Fort Lauderdale.Spring break in Florida dates back to the late 1920s in Palm Beach. Wealthy New England families spent their winters …

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Differential Coupling Of Rgs3s And Rgs4 To Gpcr-Girk Channel Signaling Complexes, Cristina Jaén Jan 2006

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, …

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Tampa’S Lafayette Street Bridge: Building A New South City, Lucy D. Jones Jan 2006

Tampa’S Lafayette Street Bridge: Building A New South City, Lucy D. Jones

USF Tampa Graduate Theses and Dissertations

The late nineteenth and early twentieth century was a time of dynamic social and political change for Tampa, a growing city on Florida's west coast. These changes led Tampa's commercial-civic elite to look beyond the law, the militia, and the church for ways to maintain their sense of order. This thesis illustrates non-violent enforcement of the status quo via public works, specifically bridge construction over the Hillsborough River. Over a period of three decades, three different bridges were built at the same place, at Lafayette Street. Each time the bridge was built or replaced, it was ostensibly for a different …

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Reef Recovery Following The Late Devonian Mass Extinction: Evidence From The Dugway Range, West-Central Utah, Joseph G. Krivanek Jan 2006

Reef Recovery Following The Late Devonian Mass Extinction: Evidence From The Dugway Range, West-Central Utah, Joseph G. Krivanek

USF Tampa Graduate Theses and Dissertations

The biotic crisis of the Late Devonian Period involved three distinct peaks of extinction intensity and preferentially eliminated reef taxa. By the end of the second peak, the Frasnian-Famennian (F-F) boundary, the dominant constructor guild member of the mid-Paleozoic, the stromatoporoids, had ceased reef construction in most parts of the world. An undescribed stromatoporoid bioherm in the Dugway Range, west-central Utah, is one of the few locations where stromatoporoids continued building reefs into the mid-Famennian. The sections are well-constrained biostratigraphically using both conodonts and stromatoporoids and range from the latest Frasnian to the Early Carboniferous. The reefal faunas are depauperate …

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Laboratory Analysis Of Staphylococcus Aureus In Florida From January 1, 2003 To December 31, 2005 With An Emphasis On Methicillin Resistance, Stephanie Kolar Jan 2006

Laboratory Analysis Of Staphylococcus Aureus In Florida From January 1, 2003 To December 31, 2005 With An Emphasis On Methicillin Resistance, Stephanie Kolar

USF Tampa Graduate Theses and Dissertations

The Staphylococci are gram-positive bacteria that cause infections in humans and can produce severe morbidity and mortality. Methicillin resistant S. aureus (MRSA) isolates are resistant to all beta-lactam antibiotics, such as methicillin, and cephalosporins making treatment of these infections more difficult. MRSA has become prevalent throughout the United States, spreading in the health care setting and the community.The purpose of this study is to examine methicillin resistance among S. aureus isolates in an outpatient population in the state of Florida and asses possible associations between methicillin resistance and age group, gender, and geographic area. It is important to define methicillin …

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Occupancy And Function Of The Hepatic Hmg-Coa Reductase Promoter, William Raymond Lagor Jan 2006

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 …

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The Signature Poetics Of Sharon Olds And John Cage, Walter E. Lewallen Jan 2006

The Signature Poetics Of Sharon Olds And John Cage, Walter E. Lewallen

USF Tampa Graduate Theses and Dissertations

This dissertation studies and applies the signature theory of Jacques Derrida to two American poets, Sharon Olds and John Cage. I begin by looking at the two texts by Derrida that most closely apply signature theory to poetics: Glas and Signsponge. Along the way, I narrow the scope of Derrida's writing somewhat by focusing on psychoanalytic aspects that relate to Jacques Lacan's ideas and to the concept of the superego. From this work I isolate some protocols for reading, which are then used to study Olds and Cage, two poets who have clearly developed their own signature styles. Here are …

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Electrically Charged Sol-Gel Coatings For On-Line Preconcentration And Analysis Of Zwitterionic Biomolecules By Capillary Electrophoresis, Wen Li Jan 2006

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 …

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Cannabinoids Suppress Dendritic Cell-Induced T Helper Cell Polarization, Tangying (Lily) Lu Jan 2006

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 …

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Control Of Lysogeny In Marine Bacteria: Studies With Φhsic And Natural Populations, Amy K. Long Jan 2006

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 …

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Breathing Easier: Ethnographic Study Of Acute Respiratory Infection In Children In Rural Ecuador, John S. Luque Jan 2006

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. …

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Endothelial Cell Mediators Of Angiogenesis InBartonella Henselae Infection, Amy M. Mccord Jan 2006

Endothelial Cell Mediators Of Angiogenesis InBartonella Henselae Infection, Amy M. Mccord

USF Tampa Graduate Theses and Dissertations

Bacillary angiomatosis (BA), one of the clinical manifestations resulting from infection with the facultative intracellular bacterium Bartonella henselae, is characterized by angiogenic lesions. Endothelial cells have been identified as host cells for this pathogen and are presumed important for pathogenesis as lesions contain bacteria in direct contact with the endothelium. Lesions also contain infiltrating macrophages, which contribute to the angiogenic process during B. henselae infection by secreting vascular endothelial growth factor (VEGF). While virulence factors have been characterized, and the role for macrophages in B. henselae infection has been established, endothelial cell mediators of angiogenesis have not been well defined. …

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Electrogenetherapy Of Established B16 Murine Melanoma By Using An Expression Plasmid For Hiv-1 Viral Protein R, Andrea Nicole Mccray Jan 2006

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 …

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Investigation Of The Effects Of Increased Levels Of O-Glcnac Protein Modification On Protein Kinase C And Akt, Jason Aaron Matthews Jan 2006

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, …

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Study Of The Ethical Values Of College Students, Victor Mercader Jan 2006

Study Of The Ethical Values Of College Students, Victor Mercader

USF Tampa Graduate Theses and Dissertations

This study focuses on five main purposes, all of them interrelated and each focused on ethical values, virtues, or character values. The five purposes are: a) Investigate college students' perceptions of ethical values, including their importance, application, usefulness, origin, benefits, need for education, and courses proposed to be included in the curricula; b) Review literature in areas related to ethical values, virtues or character values of college students; c) Develop and pilot an instrument to assess the ethical values of college students; d) Improve and use the developed instrument to describe the status of college students' ethical values; and e) …

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Goal Conflicts, Self-Regulation, And Course Completion: A Comparison Of Web-Based Learners To Traditional Classroom Learners, Barbara Moore Jan 2006

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 …

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Developing Culture Conditions To Study Keratocyte Phenotypes In Vitro, Kurt Musselmann Jan 2006

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 …

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Effects Of Translocation On The Florida Burrowing Owl, Athene Cunicularia Floridana, Per Anders Nixon Jan 2006

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 …

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Thermal Analyses Of Hydrophilic Polymers Used In Nanocomposites And Biocompatible Coatings, Kadine Mohomed Jan 2006

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 …

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Measurement Of Nerve Growth Factor In Induced Sputum And Exhaled Breath Condensate, Victor Maduabuchi Nwiloh Jan 2006

Measurement Of Nerve Growth Factor In Induced Sputum And Exhaled Breath Condensate, Victor Maduabuchi Nwiloh

USF Tampa Graduate Theses and Dissertations

Several tests are available for evaluation of respiratory disorders but most of them are invasive and associated with some risk or patient discomfort. Examples include bronchoscopy (bronchoalveolar lavage, BAL) [1], venopuncture [2] and sputum induction [3]. Noninvasive sampling of nongaseous substances contained in expired air, collected as exhaled breath condensate (EBC) has been used to detect inflammatory markers and by-products including nitric oxide and arachidonic acid metabolites and proteins [4]. Nerve growth factor (NGF) is a protein that has been implicated in neurogenic airway inflammation and this pilot study aimed to develop a non-invasive approach for evaluation of allergic airway …

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Distribution And Habitat Characterization Of The Florida Burrowing Owl In Non-Urban Areas, Mark S. Mueller Jan 2006

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 …

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Altered Features Of Female Pigeons (Columba Livia) Elicit Preference Behavior In Male Pigeons, Tadd B. Patton Jan 2006

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 …

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The Science And Policy That Compels The Wetland Mitigation Of Phosphate-Mined Lands, Nejma Danielle Piagentini Jan 2006

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 …

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Clarifying The Cohesion-Performance Relationship In Teams: Backup Behavior As A Mediating Mechanism, Matthew S. Prewett Jan 2006

Clarifying The Cohesion-Performance Relationship In Teams: Backup Behavior As A Mediating Mechanism, Matthew S. Prewett

USF Tampa Graduate Theses and Dissertations

The relationship between team cohesion and team performance has been extensively studied, but behavioral mediators of this relationship have not been adequately assessed. This study proposed that backup behavior mediates the relationship between team cohesion and team performance. In addition, it was also hypothesized that team goal commitment would moderate the relationship between team cohesion and team backup behavior. 138 participants forming 46 teams of three were assigned to one of fours conditions to test this framework: high cohesion/high goal commitment, high cohesion/low goal commitment, low cohesion/high goal commitment, and low cohesion/low goal commitment. Results indicated no significant differences between …

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Group Fission-Fusion Dynamics And Communication In The Bottlenose Dolphin (Tursiops Truncatus), Ester Quintana-Rizzo Jan 2006

Group Fission-Fusion Dynamics And Communication In The Bottlenose Dolphin (Tursiops Truncatus), Ester Quintana-Rizzo

USF Tampa Graduate Theses and Dissertations

The bottlenose dolphin exhibits a fission-fusion social structure characterized by temporary associations lasting from minutes to hours. Although social structure has been described for some dolphin communities, the selective pressures affecting fission-fusion patterns and their consequences on dolphin communication are not well understood. The goals of the present study were three-fold: 1) to quantify the rate with which fission-fusion occurred and identify the selective pressures influencing an individual's decision to leave and join a temporary group; 2) to examine the communication signals produced during temporary separations; and 3) to estimate the distances over which dolphins could remain in acoustic contact …

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Effects Of Gopher Tortoise (Gopherus Polyphemus) Translocation On Movements, Reproductive Activity, And Body Condition Of Resident And Translocated Individuals In Central Florida, Susannah Christina Riedl Jan 2006

Effects Of Gopher Tortoise (Gopherus Polyphemus) Translocation On Movements, Reproductive Activity, And Body Condition Of Resident And Translocated Individuals In Central Florida, Susannah Christina Riedl

USF Tampa Graduate Theses and Dissertations

Human-caused destruction of xeric habitats in Florida that support gopher tortoises (Gopherus polyphemus Daudin) is occurring at a rapid rate. One conservation strategy that has been used for numerous taxa is translocation. The effects of translocation on the health, reproductive activity, and movements of translocated and resident telemetered individuals was evaluated for a population of gopher tortoises in central-Florida from 2001 to 2004. Only one of the 13 individuals released left the site during the study. The home range estimates of resident individuals were not significantly different before and after the release of the translocated individuals on the site, and …

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Structure And Dynamics Of Heterogeneous Molecular Systems, Alfred B. Roney Jan 2006

Structure And Dynamics Of Heterogeneous Molecular Systems, Alfred B. Roney

USF Tampa Graduate Theses and Dissertations

Although current classical force fields describe homogeneous single-componentsystems fairly well, they do not represent the response of an individual molecule's electronic structure to its local environment with enough detail to reliably predict atomic motions in interfacial regions such as a solvation structure or liquid surface.Since most chemical processes of non-trivial interest involve two or more dissimilar molecules interacting at a short distance, molecular models must accurately simulate the interactions between different molecular species as well as bulk behavior in order to provide useful information. Results from two simulation studies are presented to illustrate both the utility of current point-charge electrostatics …

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Regulation Of Transcription And Analysis Of Drug Targets In Lymphoma And Myeloma Cells, Noah L. Silverman Jan 2006

Regulation Of Transcription And Analysis Of Drug Targets In Lymphoma And Myeloma Cells, Noah L. Silverman

USF Tampa Graduate Theses and Dissertations

The passage of two major hurricanes across southwest Florida (Category 5, Labor Day Hurricane of 1935; Category 4, Hurricane Donna 1960) resulted in fragmentation of mangrove forest at Big Sable Creek, Everglades National Park. Over time forest fragmentation led to forest loss and patchy conversion to unvegetated mudflats. My goal was to determine the consequence of forest fragmentation on nekton (i.e., fish and decapod crustaceans) inhabiting the intertidal zone. I used block nets across intertidal rivulets to compare nekton leaving replicate forest and unvegetated mudflat sites from October, 2002 through April 2004. Overall nekton density (individuals per 100 m3) was …

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Heme Biosynthesis: Structure–Activity Studies Of Murine Ferrochelatase, Zhen Shi Jan 2006

Heme Biosynthesis: Structure–Activity Studies Of Murine Ferrochelatase, Zhen Shi

USF Tampa Graduate Theses and Dissertations

Ferrochelatase catalyzes the terminal step of heme biosynthesis by inserting ferrous iron into protoporphyrin IX. The current study is aimed at understanding the structural basis of porphyrin binding and distortion in ferrochelatase-catalyzed reaction by functional analysis of a highly conserved active site loop motif. The loop was shown to contact bound porphyrin based on crystallographic and molecular modelling observations, and its role in murine ferrochelatase was assessed by random mutagenesis and steady-state kinetic analysis. To overcome the limitations of conventional kinetic assay methods for ferrochelatase, a continuous assay was developed by monitoring porphyrin fluorescence decrease using natural substrates ferrous iron …

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Holocene Climate And Hydrologic Changes Recorded In Tufa And Lacustrine Deposits In Southern Yemen, Kirk M. Sander Jan 2006

Holocene Climate And Hydrologic Changes Recorded In Tufa And Lacustrine Deposits In Southern Yemen, Kirk M. Sander

USF Tampa Graduate Theses and Dissertations

Tufa and lacustrine deposits are useful paleoclimate archives in reconstructing the early to middle Holocene climate and paleohydrology of southern Yemen's Wadi Idim and Wadi Sana, which are north-flowing tributaries to Wadi Hadramawt. Numerical age estimates and oxygen-isotopes are used to assess the onset and cessation of tufa formation and reconstruct the environment of lacustrine sediment deposition in the region in order to understand the broader early to middle Holocene hydrologic system.Numerical age estimates from the studied wadis show a correspondence between early to mid-Holocene humid-phase sediment deposition and the northward shift of the ITCZ, as documented in paleoclimate records …

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