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Self-Alignment Of Silicon Microparts On A Hexadecane-Water Interface By Surface Tension, Caroline Elizabeth Liberti

USF Tampa Graduate Theses and Dissertations

Mechanical assembly of systems and structures on the micro-scale can be inefficient as particles of sub-millimeter dimensions are difficult to manipulate. Cutting edge manufacturing methods implement self-assembly as an approach to ordering micro and nano-sized parts into a desired arrangement. This thesis studies a technique utilizing surface tension as a method of actuating microparts on a liquid-liquid interface via lateral capillary interactions. Preliminary experimentation is conducted to investigate the feasibility of developing a new method for self-alignment of microparts by observing the influence of interfacial geometry on the movement of silicon tiles along a hexadecanewater interface. Different surface geometries are …

Performance Assessment Of Predicted Heat Strain In High Heat Stress, Ronald Eugene Long

USF Tampa Graduate Theses and Dissertations

Heat stress is a common physical agent associated with many occupations. The most commonly used method of assessing heat stress exposure is an empirical method using the Wet Bulb Globe Temperature Index but his method is limited in its ability to parse out individual contributors to the heat stress. The International Organization for Standardization (ISO) published a rational model called Predicted Heat Strain (PHS) in 2004, and rational methods have the advantage of separating out the individual pathways for heat exchange. The objective of this research was a performance assessment of the current PHS model. This experimental design consisted of …

The Search For The Missing Mantles Of Differentiated Asteroids: Evidence From Taxonomic A-Class Asteroids And Olivine-Dominated Achondrite Meteorites, Michael Peter Lucas

USF Tampa Graduate Theses and Dissertations

The apparent rarity of taxonomic A-class asteroids poses a significant paradox for understanding asteroid differentiation and the dynamical evolution of the early solar system. Based on results from asteroid taxonomic surveys, and on the abundances and mineralogy of different achondrite meteorites, it appears that olivine-dominated mantle remnants are missing from both the asteroid population and in meteorite collections. Several scenarios to explain this paradox have been proposed: (1) olivine mantle material has been stripped away by collisions and only remains as small fragments (< ~5 km), (2) A-class asteroids are abundant but have been altered in some way masking their presence, or (3) differentiated asteroids did not form thick olivine-rich mantles.

We have approached these questions through the collection of taxonomic and observational data on known A-class …

Crystal Engineering Of Pharmaceutical Cocrystals, Sreya Mukherjee

USF Tampa Graduate Theses and Dissertations

Pharmaceutical cocrystals use principles of crystal engineering for the design of crystalline forms of drugs and can improve their solubility, bioavailability, stability and other important properties without changing the efficacy of the drug. Herein reported are pharmaceutical cocrystals of two API's, caffeine and Pentoxifylline.

Research has indicated that caffeine has the ability to reverse AB; plaque deposition in the brain (believed to be the primary cause of Alzheimer's pathogenesis) and thus revert memory and improve cognitive impairment. But owing to the fast absorption rate and short half life, a controlled release formulation of caffeine would be clinically beneficial. Thus, novel …

New Media Photographic Representations Of Women`S Collegiate Volleyball: Game Faces, Action Shots, And Equipment, Alicia Pack

USF Tampa Graduate Theses and Dissertations

Researchers consistently find that mainstream media often represent women athletes in stereotypical ways including trivialization, sexualization, infantilization, passivity, and utilization of camera down-angles. However, research on new media's visual representation of women athletes is still in its infancy. This study adds to the growing literature on new media's representation of women athletes and concurs with previous findings suggesting that new media might be an outlet that can counter old media gender stereotypes. This thesis used mixed methods of qualitative content analysis and photovoice in order to better understand how Big East volleyball players are represented in photographs on websites: Instances …

Natural Product Drug Discovery Against Tropical Diseases, Wai Sheung Ma

USF Tampa Graduate Theses and Dissertations

This dissertation describes the isolation of secondary metabolites from natural origins through a series of chromatographic techniques and spectrometric characterization in the effort of drug discovery. The isolated compounds obtained were used as drug leads against tropical diseases, namely malaria and leishmaniasis. While first chapter offers an introduction on the use of a natural product by itself as an effective therapeutic and its role on inspiring the discovery of new drugs, the later chapters will concentrate on isolation and characterization of bioactive natural products from an Antarctic sponge and mangrove endophytic fungi during the dissertation work.

The second chapter describes …

Numeracy, Cancer Risk Perceptions, And Self-Protective Behaviors Among U.S. Adults, Teri Malo

USF Tampa Graduate Theses and Dissertations

Individuals have become more involved in health-related decisions, in part due to an unprecedented access to information that can be used to enhance both physical and mental health. Much of this health-related information is presented in a numerical format; unfortunately, research suggests many Americans may not possess the literacy skills necessary to comprehend numerical health-related information. More research needs to be conducted to examine numeracy and its role in cancer risk perceptions, and how those risk perceptions relate to cancer self-protective behaviors. The purpose of the current study was to: (a) examine socio-demographic variables associated with numeracy, (b) determine which …

Automorphism Groups Of Quandles, Jennifer Macquarrie

USF Tampa Graduate Theses and Dissertations

This thesis arose from a desire to better understand the structures of automorphism groups and inner automorphism groups of quandles. We compute and give the structure of the automorphism groups of all dihedral quandles. In their paper Matrices and Finite Quandles, Ho and Nelson found all quandles (up to isomorphism) of orders 3, 4, and 5 and determined their automorphism groups. Here we find the automorphism groups of all quandles of orders 6 and 7. There are, up to isomoprhism, 73 quandles of order 6 and 289 quandles of order 7.

Impacts Of Artificial Reefs On Surrounding Ecosystems, Sarine Manoukian

USF Tampa Graduate Theses and Dissertations

Artificial reefs are becoming a popular biological and management component in shallow water environments characterized by soft seabed, representing both important marine habitats and tools to manage coastal fisheries and resources. An artificial reef in the marine environment acts as an open system with exchange of material and energy, altering the physical and biological characteristics of the surrounding area. Reef stability will depend on the balance of scour, settlement, and burial resulting from ocean conditions over time. Because of the unstable nature of sediments, they require a detailed and systematic investigation.

Acoustic systems like high-frequency multibeam sonar are efficient tools …

Chemical Investigation Of The Antarctic Marine Invertebrates Austrodoris Kerguelenensis & Dendrilla Membranosa And The Antarctic Red Alga Gigartina Skottsbergii, John Alan Maschek

USF Tampa Graduate Theses and Dissertations

The marine realm and, in particular, the Antarctic benthos is largely unexplored and understudied. The chemical investigation reported herein reveals not only the biodiversity, but how that biodiversity manifests remarkable chemical diversity. In our continuing study of the nudibranch Austrodoris kerguelenensis, we have isolated a diverse suite of diterpenoid glyceride esters, palmadorins D - S (2.32 - 2.47), one of which is the first reported halogenated diterpene from a dorid nudibranch. Utilizing genomic data from collaborators, we have investigated the chemical diversity from phylogenetically unique specimens collected in close proximity to one another. Chemical groupings based on comparison of LC/MS …

The Influence Of Meteorological Parameters On Rainfall And Severe Weather In Pinellas County, Fl, Cristina A. Mazza

USF Tampa Graduate Theses and Dissertations

Pinellas County is located on a peninsula in Florida that experiences daily patterns of sea breeze associated rainfall mainly during the summer months of June through August. Previously, rainfall patterns, amounts and timing and severe weather in Pinellas County have not been examined considering dominant wind flow patterns, sea breeze circulations and other atmospheric variables. To improve forecasting of local mesoscale phenomena, this project examined the rainfall patterns, amounts and timing and severe weather occurrences that occur as a result of sea breezes and associated prevailing wind regimes within Pinellas County for the months of June, July and August for …

Seasonal Changes In The Sinking Particulate Flux And In The Nitrogen Cycle Within The Euphotic And Twilight Zones Of The Cariaco Basin, Venezuela, Enrique Montes-Herrera

USF Tampa Graduate Theses and Dissertations

This study explored the effects of seasonal variability on the geochemistry of sinking pthesiss and on the nitrogen cycle of the Cariaco Basin. Pthesis fluxes were measured at the base of the euphotic zone (the depth of 1% of photosynthetically active radiation - PAR) with drifting sediment traps during months of upwelling and non-upwelling regimes from March 2007 to November 2009. Flux estimates were analyzed in the context of seasonal variations in sea surface temperature, primary productivity, and chlorophyll a concentrations using data generated by the CARIACO Time-series Program as well as satellite data. Additionally, nine years (1996-2000 and 2004-2007) …

Atomistic Studies Of Shock-Wave And Detonation Phenomena In Energetic Materials, Mikalai Budzevich

USF Tampa Graduate Theses and Dissertations

The major goal of this PhD project is to investigate the fundamental properties of energetic materials, including their atomic and electronic structures, as well as mechanical properties, and relate these to the fundamental mechanisms of shock wave and detonation propagation using state-of-the-art simulation methods. The first part of this PhD project was aimed at the investigation of static properties of energetic materials (EMs) with specific focus on 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). The major goal was to calculate the isotropic and anisotropic equations of state for TATB within a range of compressions not accessible to experiment, and to make predictions of anisotropic sensitivity …

The Development Of The Personal Strengths Intervention (Psi) To Improve Self-Determination And Social-Emotional Levels In Postsecondary Students With Learning Disabilities And/Or Adhd: A Multiple Baseline Study, Jennie L. Farmer

USF Tampa Graduate Theses and Dissertations

Students with learning disabilities and/or attention deficit hyperactivity disorder (ADHD) experience decreased academic and social-emotional outcomes when compared to their peers without disabilities. Self-determination, positive psychology, and cognitive theories of learning offer suggestions for improving these outcomes. The purpose of this study was to develop The Personal Strengths Intervention (PSI) and investigate its impact on levels of self-determination and the social-emotional functioning of postsecondary students with learning disabilities and/or ADHD. PSI integrates key elements of self-determination, positive psychology, and cognitive theories. ADHDA multiple baseline design with seven participants was used to examine the intervention effects over time. Results indicate PSI …

A Pilot Study Of Small-Scale Variations In Outdoor Benzene Concentrations, Samantha Catherine Fridh

USF Tampa Graduate Theses and Dissertations

Benzene is an important toxic chemical in urban air and known human carcinogen released substantially by mobile sources. It's important to understand the spatial variation of benzene concentrations in order to understand exposures of susceptible sub-populations such as children and minority groups. Current monitoring networks use large and expensive air samplers that require electricity and restrict the location and number of samplers, not allowing for fine spatial resolution data.

The goals of this study are to develop and evaluate protocols for passive sampling and analysis of ambient benzene concentrations, and conduct a pilot study investigating small-scale variations over an area …

A Reflective Exploration Of A Multiyear Elementary School Learning Community Experience, Susan Jean Ganley

USF Tampa Graduate Theses and Dissertations

This study reports a reflection upon the experience of a multiyear elementary school learning community designed for improved teaching and learning. The exploration uses interview data to describe the perceptions and reflections of the principal and teachers directly engaged in this project of educational reform. The goal of this process is to gain a deeper understanding of the experience and to determine to what factors the participants attribute the outcomes of this project.

Through an auto-ethnographic reflective critical practice inquiry and extended interviews, this study describes the context and environment of this learning community and how the participants reflect on …

Synthesis Of Small Molecule Inhibitors Of Janus Kinase 2, Phosphodiesterase Iv, Gabaa And Nmda Receptors: Investigation Of Mcmurry, Mannich And Chemoenzymatic Strategies, Meghanath Gali

USF Tampa Graduate Theses and Dissertations

Stilbenoids possess a wide range of biological properties such as, anticancer, antiplatelet aggregation, antiestrogenic, antibacterial, antifungal and antiatherogenic, etc. Owing to these therapeutic values, a great deal of attention attracted in the synthesis of derivatives of stilbenes. During the course of the study, G6 a novel stilbenoid was discovered, through high throughput screening, to be a potent inhibitor of mutated JAK2-V617F. The mutated JAK2 variant has been implicated in various myeloproliferative disorders (MPDs) including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) has been targeted by therapeutics. Chapter 2 describes the synthesis of analogs of the stilbenoid G6 …

Electronic Structure Characterization Of Nanocrystalline Surfaces And Interfaces With Photoemission Spectroscopy, Sebastian Gutmann

USF Tampa Graduate Theses and Dissertations

In this study, photoemission spectroscopy (PES) was used to investigate the electronic properties of nanocrystalline titanium dioxide (TiO₂), zinc oxide (ZnO), and cadmium selenide (CdSe). Electrospray deposition technique enabled the preparation of thin films in vacuum from a dispersion prepared outside the vacuum chamber. This method also allowed the step-wise formation of interfaces and the monitoring of the evolution of the electronic structure with intermittent PES characterization.

The work function of nanocrystalline TiO₂ and ZnO was measured with ultraviolet photoemission spectroscopy (UPS) and low-intensity x-ray photoemission spectroscopy (LIXPS). Measurements on environmentally contaminated surfaces revealed an instantaneous and …

Statistical Analysis And Mechanistic Modeling Of Water Quality: Hillsborough Bay, Florida, Keith Hackett

USF Tampa Graduate Theses and Dissertations

Nutrient pollution has been identified as a significant threat to U.S. coastal and estuarine water quality. Though coastal and estuarine waters need nutrients to maintain a healthy, productive ecosystem, excess nutrients can lead to eutrophication. There are significant potential negative consequences associated with eutrophication, including loss of habitat, loss of economic activity, and direct threats to human health. Hillsborough Bay experienced eutrophication in the 1960s and 1970s due to a rapidly growing population and associated increases in nutrient pollution. These eutrophic conditions led to more frequent phytoplankton and macroalgae blooms and declines in seagrasses. To address these problems, a series …

Physical Models Of Amyloid Fibril Assembly, Shannon Elizabeth Hill

USF Tampa Graduate Theses and Dissertations

Formation of large fibers and plaques by amyloid proteins is recognized as the molecular hallmark of an increasing number of human disorders, including Parkinson's disease, Alzheimer's disease and even type II diabetes. The broader objective of my research is to unravel the basic mechanisms that initiate and regulate fibril formation by amyloidogenic proteins. This objective is significant because even basic aspects of how fibril formation proceeds from a soluble, monomeric protein to an insoluble amyloid fibril remain much debated. Furthermore, there is increasingly strong evidence suggesting that intermediates of the aggregation process, with properties distinct from those of mature fibrils, …

Utilizing A Computational Model For The Design Of A Passive Dynamic Walker, Craig Alan Honeycutt

USF Tampa Graduate Theses and Dissertations

Recent interest in using passive dynamic walkers (PDWs) for gait rehabilitation studies has presented a need for a robust, easily built mechanism. Unfortunately, these passive robots are hypersensitive to many variables outside of the usual design considerations that are studied when constructing them. By accentuating previous failures instead of suppressing them, this thesis presents a number of problematic situations commonly experienced when testing and tuning a PDW.

Further, through a complete design of a 4-legged PDW with knees, simple design axioms brought about by myself and others are put into a practical context and applied directly to design. This thesis …

From Source To Sink: An Isotopic Perspective On The Biogeochemical Relationship Between The Everglades And Florida Bay, Ana Maria Hoare

USF Tampa Graduate Theses and Dissertations

Increasing human populations and activities in coastal areas have led to high nutrient loading and estuarine ecosystem decline. Natural hydrological patterns in South Florida have been drastically altered by changes in water management and land use practices. As a result Florida Bay has experienced a series of negative ecosystem effects including hypersalinity events, degradation of water quality, and harmful algal blooms and declines in upper trophic level populations. To remediate ecosystem decline in Florida's coastal ecosystems, the Comprehensive Everglades Restoration Plan proposes to restore a more natural hydrologic flow in the Everglades. It is expected hydrologic restoration efforts will change …

Informal Karst Education In The United States And Internationally, Leslie A. North

USF Tampa Graduate Theses and Dissertations

Despite the abundance of karst terrains and the important role they play in a wide variety of roles including supplying freshwater drinking supplies, no single, comprehensive study investigates the role of informal education for the improved understanding and protection of the terrains. Commonly overlooked anthropogenic karst disturbances partially occur because of the poor dissemination of scientific information to the general populace and policymakers and budgetary and time constraints of municipalities, thus generating a need to use informal education to fill these shortcomings. The purpose of this study was to: 1) establish the status of and quantify the amount of karst-related …

Synthesis And Antimicrobial Activities Of S,S'-Heterosubstituted Disulfides, Praveen Ramaraju

USF Tampa Graduate Theses and Dissertations

Antibiotic resistance is a particularly critical health concern and has increased dramatically over the past two decades. For over a decade the Turos laboratory has been designing small molecules to target pathogenic microbes such as Staphylococcus aureus and the resistant variants like methicillin-resistant Staphylococcus aureus (MRSA). Previously, N-thiolated Β-lactams, N-thiolated 2-oxazolidinones and aromatic disulfides that were synthesized in Dr. Turos' lab have shown strong activity against these bacteria. The present work describes the synthesis and antimicrobial activities of a related structural class called S,S'-heterosubstituted disulfides. For ages, sulfur (elemental) has been used as an antibacterial for controlling infestation and bacterial …

Guiding Electric Fields For Electroporation Applications, Jose Rey

USF Tampa Graduate Theses and Dissertations

Electroporation is the critical step in an electric field mediated drug or gene delivery protocol. Electroporation based protocols have been successfully demonstrated in cancer clinical trials, however, its impact in other applications is still under investigation. A significant roadblock to long term functioning of implantable biosensors in vivo is the tissue reaction in the form of fibrous encapsulation that results in reduced transport to the sensing element of the biosensor. In vivo gene electroporation has a great potential as a means to modify the transport properties of tissues in the proximity of the sensing element of implantable biosensors.

This dissertation …

Effects Of Solids Loadings And Particle Size Distribution On Siphon Ceramic Candle Filters, Danielle Renzi

USF Tampa Graduate Theses and Dissertations

In the rural areas of Madagascar only 29% of the population has access to clean water and 10% has access to improved sanitation. It has been estimated that environmental risk factors, such as inadequate access to clean drinking water and proper sanitation, are responsible for 94% of the diarrheal disease burden. This study was focused on testing a point-of-use technology called the Tulip filter, which is a siphon ceramic candle filter impregnated with silver. The purpose is to assess its feasibility for implementation in rural regions of Madagascar through a laboratory study performed at the University of South Florida.

The …

Improvements To A Real-Time, Satellite-Derived Surface Current Product (Oscar) And Evaluation In The Intra-American Sea, Mindy Jo Robinson

USF Tampa Graduate Theses and Dissertations

A method of creating real-time height fields using available gridded altimetry data combined with extrapolated values computed using linear predictive coding for use in the Ocean Surface Currents Analysis, Real-time (OSCAR) is developed and tested. This method is implemented by Earth and Space Research (ESR) to produce operational height fields that are in turn used to calculate the geostrophic component velocity of OSCAR. The gridded altimetry product used in OSCAR is evaluated against sea level measured by tide gauges while the operational total near-surface velocity from OSCAR (geostrophic plus Ekman component velocity) is evaluated using ocean velocities from moored and …

Apparent Total Evaporative Resistance For Clothing Ensembles At High Heat Stress Levels, Patrick Rodriguez

USF Tampa Graduate Theses and Dissertations

Donning protective clothing for mitigation of hazard from chemical agents poses a problem in the form of heat stress. When choosing protective clothing, many factors must be taken into account including insulative properties and evaporative resistance. This study calculated and compared R_e,T,a for three clothing ensembles at levels of heat stress past the level of compensation for heat gain to determine if R_e,T,a values varied or remained the same with changes in heat stress level. A three-way mixed model analysis of variance demonstrated significant differences for estimated R_e,T,a values among ensembles, heat stress levels and interactions among …

Gaming Literacy: Construct Validation And Scale Construction, Kenneth Allen Rosenberg

USF Tampa Graduate Theses and Dissertations

This thesis is the first attempt to construct a standardized measure of literacy for the medium of video games, filling a gap in the literature by synthesizing various items of skills, behaviors, and affective components from existent studies and determining their correlations through analyzation of survey data. The five categories that were derived from conceptual review and factor analysis have high measures of internal consistency: Information and Systems Management; Exploration and Enjoyment; Teamwork; Design; and Socialization. To test for external consistency and reliability, the proposed gaming literacy model was compared to the Novak and Hoffman (1997) construction of flow, using …

Design Of Small Scale Anaerobic Digesters For Application In Rural Developing Countries, Laurel Erika Rowse

USF Tampa Graduate Theses and Dissertations

The high incidence of upper respiratory diseases, contamination of waterways due to pathogens and nutrients from human and animal wastes, unsustainable deforestation, gender disparities in burden of disease due to unequal exposure to indoor air pollutants, and carbon black emissions from the burning of solid fuels are interrelated problems in many developing countries. Small scale anaerobic digestion provides a means of alleviating these problems by treating livestock waste onsite to produce biogas (methane and carbon dioxide) in rural areas in developing countries. Fuel can then be used for cooking, lighting, and heating. Methane fuel is an alternative to traditional three-stone …