Physical Sciences and Mathematics Commons^™

Exploration Of Factors Associated With Perceptions Of Community Safety Among Youth In Hillsborough County, Florida: A Convergent Parallel Mixed-Methods Approach, Yingwei Yang

USF Tampa Graduate Theses and Dissertations

Introduction: Youth perceived safety is not only linked to crime and violence in a neighborhood but is also associated with health risk behaviors and certain neighborhood characteristics. The purpose of this mixed-methods study was to measure the co-occurring effects of individual and community risk factors by conducting a secondary data analysis using structural equation modeling (SEM) and to explore reasons for youth feeling safe/unsafe in their community using photovoice methodology.

Methods: Syndemic theory/model served as the theoretical framework to guide this mixed-methods study with a convergent parallel design. The quantitative strand (first manuscript) utilized an existing dataset collected from middle …

Shallow Water Seafloor Geodesy: Gps On An Anchored Spar Buoy, Surui Xie

USF Tampa Graduate Theses and Dissertations

Measuring seafloor motion in shallow coastal water is challenging due to strong and highly variable oceanographic effects. Such measurements are potentially useful for monitoring near-shore coastal subsidence, subsidence due to petroleum withdrawal, strain accumulation/release processes in marine shelves and submerged volcanoes, and certain fresh water applications, such as volcano deformation in caldera-hosted lakes. I participated in a project to develop a seafloor geodetic system for this environment based on an anchored spar buoy topped by high precision GPS. Orientation of the buoy is measured using a digital compass that provides heading, pitch, and roll information. The combined orientation and GPS …

Bayesian Reliability Analysis Of The Power Law Process And Statistical Modeling Of Computer And Network Vulnerabilities With Cybersecurity Application, Freeh N. Alenezi

USF Tampa Graduate Theses and Dissertations

As most of mankind now lives in an era of high dependence on multiple technologies and complex systems to store and manage sensitive information, researchers are constantly urged to obtain and improve measurements and methodologies that have the ability to evaluate systems reliability and security. The objectives of the present dissertation are to improve the Bayesian reliability estimation of a software package where the Power Law Process, also known as Non-Homogeneous Poisson Process, is the underlying failure model and to develop a set of statistical models evaluating computer operating systems vulnerabilities. Furthermore, we develop a reliability function of a computer …

Non-Associative Algebraic Structures In Knot Theory, Emanuele Zappala

USF Tampa Graduate Theses and Dissertations

In this dissertation we investigate self-distributive algebraic structures and their cohomologies, and study their relation to topological problems in knot theory. Self-distributivity is known to be a set-theoretic version of the Yang-Baxter equation (corresponding to Reidemeister move III) and is therefore suitable for producing invariants of knots and knotted surfaces. We explore three different instances of this situation. The main results of this dissertation can be, very concisely, described as follows. We introduce a cohomology theory of topological quandles and determine a class of topological quandles for which the cohomology can be computed, at least in principle, by means of …

Classifying Emotions With Eeg And Peripheral Physiological Data Using 1d Convolutional Long Short-Term Memory Neural Network, Rupal Agarwal

USF Tampa Graduate Theses and Dissertations

Recognizing emotions is very important while building robust and interactive Affective Brain-Computer Interfaces as it allows the machines to have some degree of emotional intelligence with the help of which they can understand the changing emotional state of users. In the past, emotions have been recognized via unimodal data such as electroencephalography (EEG) signals, speech, facial expressions or peripheral physiological signals. However, emotions are complex as they are a combination of human behavior, thinking and feeling. Therefore, as compared to unimodal methods, multi-modal techniques, recognize emotions with more reliability. This thesis aims to recognize and classify human emotions into high/low …

Advancing Equity Amongst General Chemistry Students With Variable Preparations In Mathematics, Vanessa R. Ralph

USF Tampa Graduate Theses and Dissertations

Reducing the inequities propagating the lack of representation in Science, Technology, Engineering, and Mathematics (STEM) careers has become a national imperative made increasingly complex given the inequitable preparations in science and mathematics students experience before college. A common institutional-level approach to promoting equity is the use of math and science prerequisites to prepare students who seek to enroll in lower-level STEM coursework. However, the literature does not support the efficacy of this approach, finding no substantive improvement to student performance despite considerable financial and time costs to students, instructors, and universities alike. Set in first-semester General Chemistry courses taken early …

Differential Mobility Spectrometry-Mass Spectrometry (Dms-Ms) For Forensic And Nuclear-Forensic Applications, Ifeoluwa Ayodeji

USF Tampa Graduate Theses and Dissertations

In forensics and nuclear-forensics, the current lab-based analytical technique employed can be laborious, time consuming, and less suitable for in-situ and real time screening. However, it is important to develop fast and fieldable instrumental technique, without a tradeoff for its high throughput, for drug screening and radionuclear analysis. The underlying factors to be considered in the instrument development ranges from: high potency of samples, even at very low concentration; complex nature of samples in the surrounding environment; real-time chemical composition variation; and instrument size, weight and power (SWAP) consideration. Differential mobility spectrometry (DMS), also known as field asymmetric waveform ion …

Rainfall, Precipitation, And Drought Patterns Associated With Wintertime Transmission Of Eastern Equine Encephalitis Virus (Eeev) In Florida, Bestami Cevher

USF Tampa Graduate Theses and Dissertations

Eastern Equine encephalitis virus (EEEV) is a highly pathogenic alphavirus that causes disease in humans and horses. EEEV cases are common in the eastern North America, especially in horses in the State of Florida. EEEV cases are most common in Florida during May to August but also occur year-round, unlike most other locations. According to the Florida Department of Health, 65 EEEV horse cases were documented in the winter months between 2005 and 2018. This study investigates the meteorological activities that affect the wintertime transmission of the EEEV virus to horses. In this, we examined meteorological data up to a …

Gradient Boosting For Survival Analysis With Applications In Oncology, Nam Phuong Nguyen

USF Tampa Graduate Theses and Dissertations

Cancer is one of the most deadly diseases that the world has been fighting against over decades. An enormous number of research has been conducted, via a wide scale of approaches, raging from genetic analysis to mathematical modeling. Survival analysis is a well-performed methodology frequently used to estimate the survival probability of a patient. Although there has been a large number of methods for survival analysis, efficient exploration of a high-dimensional feature space has been challenging due to its computational cost and complexity. This thesis adapts the component-wise gradient boosting algorithms for cancer survival analysis, and also proposes a new …

Chemical Tools And Treatments For Neurological Disorders And Infectious Diseases, Andrea Lemus

USF Tampa Graduate Theses and Dissertations

Neurological disorders have multiple etiologies such as genetics and age. Stress related disorders are becoming more common and diagnosed more often. Mental health disorders are no longer being treated as purely psychological. Mechanisms into the underlying factors of these disorders continue to bring this area to new frontiers. Chapter 2 of this dissertation focuses on the efforts made to prove the association of the protein FKBP51 to the stress response. We synthesized and used a molecular tool to discover and prove these interactions.

The study of neurodegenerative diseases is of continued importance as the world reaches record numbers of an …

Antarctic Deep Sea Coral And Tropical Fungal Endophyte: Novel Chemistry For Drug Discovery, Anne-Claire D. Limon

USF Tampa Graduate Theses and Dissertations

Considered the pulse controlling the biological interactions and contributing to the ecological survival of organisms, natural products have intrigued, challenged, and stimulated the scientific and non-scientific minds for millennia. Drug resistance and the lack of suitable potent drugs against neglected tropical diseases further motivate the biological activity assessment of these secondary metabolites, when possible.

This thesis describes the chemical investigation of two marine organisms and the elucidation of eight novel structures.

The study of a deep sea Antarctic coral unveils six novel terpenoid structures from three different molecular classes: sesquiterpenoid alcyopterosins, a triterpene steroid, and three prostaglandins. While mass availability …

Reconstructing Geographic And Trophic Histories Of Fish Using Bulk And Compound-Specific Stable Isotopes From Eye Lenses, Amy A. Wallace

USF Tampa Graduate Theses and Dissertations

The present research examined the viability and utility of eye lenses as a source of lifetime stable-isotope records in fish. It is presented in three sections. The first section compared bulk isotopic variation (bulk analysis) within fish eye-lenses at two temporal resolutions and compared patterns obtained from left and right eyes. The first temporal resolution was lower in an attempt to expose broad-scale isotopic changes during life while reducing effort and cost. This approach did reveal lifetime patterns, but tended to miss certain life events, particularly during early life. The second resolution was higher and provided detail that was missed …

Use Of Spectrofluorometry To Detect Petroleum Hydrocarbons In The Marine Environment, Mary Iris Abercrombie

USF Tampa Graduate Theses and Dissertations

The genesis of this research was the Deepwater Horizon oil spill, which discharged petroleum and gas into the Gulf of Mexico for 87 days in 2010. High-resolution fluorescence spectroscopy was employed for the detection of petroleum in seawater samples following the oil spill. Fluorescence arises from the chemical structure of π-bonding in C=C bonds, especially those in aromatic structures. Spectrofluorometry was also used to observe and track the formation of petroleum plumes in seawater undergoing controlled physical dispersion in a wave tank, both with and without the addition of chemical dispersant. Further, the changing fluorescence characteristics of a broad range …

The Activity And Structure Of Cu2+-Biomolecules In Disease And Disease Treatment, Darrell Cole Cerrato

USF Tampa Graduate Theses and Dissertations

Despite its relatively low concentration in the human body, copper is an essential transition metal ion. Under normal circumstances, it is a well-regulated trace element that is introduced via diet or environment depending on the organism. Its strong reactivity and binding to some biologically essential chemicals can be detrimental to the host organism. Herein the oxidative chemistry of copper and its possible prevention in humans and agricultural organisms is discussed, as well as the potential avenues as metal-targeting disease treatment via novel-peptide and peptoid products.

In the first study, copper is implicated in the progression and onset of Alzheimer’s disease. …

Effect Of Atypical Protein Kinase C Inhibitor (Dnda) On Cell Proliferation And Migration Of Lung Cancer Cells, Raja Reddy Bommareddy

USF Tampa Graduate Theses and Dissertations

Lung cancer is the second most common cancer, and it is the leading cause of cancer death in both men and women. Elevated levels of PKC-ι and FAK are implicated in the progression of lung cancer and involved in cell proliferation, apoptosis, cell survival, and cell migration processes. Lung cancer diagnosis typically occurs in the late stages, which limits the treatment options. Hence, there is a dire need to develop drugs that are effective and safe to treat lung cancers. We used a novel aPKC inhibitor named DNDA (3,4-amino-2,7 napthalene disulfonic acid) to study the role of atypical PKCs (aPKCs) …

Construction Of G-Quadruplexes Via Self-Assembly: Enhanced Stability And Unique Properties, Ying He

USF Tampa Graduate Theses and Dissertations

This dissertation mainly contains three parts: 1) The construction of well-defined G8-octamers through the monomer conformational design. 2) The construction of cross-layer interactions in the G8-octamer for enhanced stability in H-bond competitive solvents. 3) Design and synthesis of 8-triazole guanosine with photoluminescent properties.

Through the structural conformational design, we have developed a new class of guanosine derivatives with modification on guanine (8-aryl) and ribose (2’,3’-isopropylidene). This unique design has led to the formation of the first discrete G8-octamer with structure characterized by NMR, MS and single crystal X-ray diffraction. The selectivity between monovalent (K+) and divalent cat-ions (Ba2+ and Sr2+) …

First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong

USF Tampa Graduate Theses and Dissertations

The investigation of materials at extreme conditions of high pressure and temperature (high-PT), has been one of the greatest scientific endeavors in condensed mater physics, chemistry, astronomy, planetary, and material sciences. Being subjected to high-PT conditions, materials exhibit dramatic changes in both atomic and electronic structure resulting in an emergence of exceptionally interesting phenomena including structural and electronic phase transitions, chemical reactions, and formation of novel compounds with never-previously observed physical and chemical properties. Although new exciting experimental developments in static and dynamic compression combined with new diagnostics/characterization methods allow to uncover new processes and phenomena at high P-T conditions, …

The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki

USF Tampa Graduate Theses and Dissertations

This dissertation explores the ecohydrology of Florida’s peculiar and poorly studied sandhill wetland and water features, particularly those located in west-central Florida. The primary research goals include: compilation and summarization of the available ecohydrologic information for features across Florida; comparison of water level and water geochemistry data between sandhill wetlands and waters and the regional aquifer to provide evidence of regional hydrologic control; and use of geophysical applications to examine the hydraulic connections between sandhill wetlands and waters and the regional aquifer.

From this research, a natural history of sandhill wetland and water ecohydrology is presented, highlighting: the differences between …

Untapped Potential Of Gorgonian Octocorals For Detecting Environmental Change In Biscayne National Park, Florida, Usa, Selena A. Kupfner Johnson

USF Tampa Graduate Theses and Dissertations

One consequence of dramatic stony-coral loss has been recognition that gorgonian octocorals (Anthozoa: Octocorallia) have emerged among the dominant reef fauna. However, gorgonians are notoriously difficult to field-identify and consequently have been underrepresented in most monitoring efforts resulting in a lack of long-term data. The rich diversity of habitats, close proximity to the urban center of Miami, and connectivity to other areas of Florida have made Biscayne National Park an active location for reef research since its establishment in 1968. As such, a plethora of data (e.g., museum specimen and species abundance data) has been collected and stored in archives …

Biomimetic Light Harvesting In Metalloporphyrins Encapsulated/Incorporated Within Metal Organic Frameworks (Mofs)., Abdulaziz A. Alanazi

USF Tampa Graduate Theses and Dissertations

The Global energy supply relies mostly on fossil fuels and only 10% comes from renewable energy. These places humankind in an unsafe situation as the fossil fuel resources won’t last forever. More efficient use of renewable energy is required sooner than later to meet the growing energy need. A promising approach is to utilize light harvesting chromophores (e.g., porphyrin derivatives) to advance organic photovoltaics and increase its efficiency or to improve photocatalysts. Metal-organic frameworks (MOFs) can be employed to aid the self-assembly of the porphyrin chromophores in a large light-harvesting system comparable to the natural photosystem. The advantage of using …

Self-Assembly Of 2d And 3d Metallo-Supramolecules With Increasing Complexity, Bo Song

USF Tampa Graduate Theses and Dissertations

Synthetic organic chemistry played a crucial role in the construction of molecules through the formation and dissociation of covalent bonds. However, the laborious synthetic procedures as well as the low yield after multiple steps have restricted the pursuit of complicated giant molecules with high efficiency. Being complementary to organic synthesis, self-assembly provided an alternative route to achieving the giant architectures using weak non-covalent interactions in high efficiency, which is in analog to natural systems such as DNA, peptide, and protein. Among the various interactions, coordination has shown unique advantages in terms of directionality, reversibility and strength. Serving as a bottom-up …

Introducing A Mobile Health Care Platform In An Underserved Rural Population: Reducing Assimilations Gaps On Adoption And Use Via Nudges, Joseph Hodges

USF Tampa Graduate Theses and Dissertations

Rural communities are often overlooked when it comes to offering cutting edge consumer healthcare technologies. Mobile applications usually exclude populations in rural demographics due to the infrastructure requirements and available technology in the region. The population studied is a low income rural health plan in southwest Georgia. They are uniquely considered as they have the highest healthcare costs in the U.S. and are compared to healthcare costs among higher income populations like Vail, Colorado. Innovations, such as mobile healthcare applications, have the capacity to offset some of these costs, but even if adoption occurs, this does not guarantee use will …

Past Climate And Sea-Level Reconstruction Using Cave Deposits From Mallorca, Spain, Oana-Alexandra Dumitru

USF Tampa Graduate Theses and Dissertations

The potential impacts of the increasing temperature on the water resources, as well as the hazards associated with the sea-level rise in the low-elevation coastal zones of the Mediterranean Sea, makes this region vulnerable to current climate change due to global warming. Hence, accurate projections of the future hydroclimate scenarios in this area are crucial. Long-term information on climate and sea-level variability cannot be obtained by direct observations or using short instrumental records. However, various geological archives may provide valuable data that can be then used to assess the models used for future predictions.

This thesis presents results on past …

Development Of Α-Aa Peptides As Peptidomimetics For Antimicrobial Therapeutics And The Discovery Of Nanostructures, Sylvia E. Singh

USF Tampa Graduate Theses and Dissertations

For decades it has been convention to use antibiotics for the treatment of bacterial infections. Due to the overuse and misuse of these drugs, bacteria are becoming resistant to these treatments. This phenomenon has led to the search for alternative antibiotics, and in the study of Host Defense Peptides (HDPs). HDPs are the body’s innate immune response to infection. They are known to modulate immune system response and kills bacterial using various methods causing them to be less susceptible to bacterial resistance. The method by which we can mimic these biological peptides is called peptidomimetics. Various research shows the use …

Design, Synthesis, And Self-Assembly Of Supramolecular Fractals Based On Terpyridine With Different Transition Metal Ions, Lei Wang

USF Tampa Graduate Theses and Dissertations

Fractals have existed in a variety of natural forms, and the concept of "fractal geometry" has been developed in many areas by humankind, including art, economics, mathematics, physics, chemistry, material science, and etc. In the field of chemistry, researchers have endeavored great efforts to express the concept using molecules either by theoretical prediction or using synthetic methods in the past few decades, and one successful example is the “Sierpiński triangle”. Challenge still remains to achieve other fractal geometries as well as high generation of fractals with precisely controlled shape and size. Coordination-driven self-assembly has witnessed a wide array of well-defined …

The Chemical Ecology And Drug Discovery Potential Of The Antarctic Red Alga Plocamium Cartilagineum And The Antarctic Sponge Dendrilla Membranosa, Andrew Jason Shilling

USF Tampa Graduate Theses and Dissertations

Chemical ecology is the study of chemical interactions between organisms and their environment mediated by small molecules involved in nonessential physiological functions, known as secondary metabolites. These compounds can be crucial to survival of the organism, and have also provided the field of medicine with some of history’s most influential drugs, referred to in that context as natural products. Antarctica is a dynamic and understudied environment, which affords the opportunity to examine the chemical ecology of unique organisms while simultaneously evaluating their novel chemistry for potential therapeutic properties as natural products.

Plocamium cartilagineum is a red macroalgal species found in …

The Adaptations Of The Sulfur-Oxidizing, Gammaproteobacterium "Candidatus Endoriftia Persephone", Endosymbiont Of The Giant Tubeworm Riftia Pachyptila, To Hydrothermal Vent Habitat Heterogeneity, Juliana M. Leonard

USF Tampa Graduate Theses and Dissertations

The siboglinid tubeworm Riftia pachyptila is a dominant member of the deep-sea megafauna where seawater and hydrothermal vent (HTV) effluent interface and mix. It is one of the fastest growing invertebrates on land or in the sea. It does not have a digestive tract (e.g. mouth, gut, or anus), and is completely dependent on its sulfur-oxidizing endosymbiont, the Gammaproteobacterium “Candidatus Endoriftia persephone” for its nutritional requirements. This association was the first and is the most well studied among chemolithoautotrophic symbioses. “Ca. E. persephone” is a chemolithoautotrophic bacterium that oxidizes sulfide as an electron donor for energy, reduces oxygen as a …

Millimeter-Wavelength Characterization Of The Co Emission Of Comets 174p/Echeclus, 29p/Schwassmann-Wachmann, And C/2016 R2 (Panstarrs), Kacper Wierzchos

USF Tampa Graduate Theses and Dissertations

Comets are fascinating minor solar system bodies. They contain some of the most pristine and unprocessed material found in the solar system. As a comet approaches the Sun it displays the characteristic cometary coma and tail. This is due to the release of volatile species through a variety of processes. In the present work I studied the carbon monoxide emission of three very unique comets; 174P/Echeclus, 29P/Schwassmann-Wachmann and C/2016 R2 (PanSTARRS) with different radio telescopes at millimeter wavelengths. After molecular hydrogen, carbon monoxide is the second most abundant molecule in the universe, and is also the most volatile of the …

Perceptions Of The Effectiveness Of Food Policy Coalitions In Strengthening Community Food Security In The United States., Joseph G. England Iii

USF Tampa Graduate Theses and Dissertations

Food insecurity is experienced most acutely and addressed most innovatively at the community level to which the concept of community food security (CFS) finds purchase (Hamm and Bellows, 2003). In recognition of the many varying dynamics embedded in the CFS concept, Food Policy Coalitions have become an organizational model adapted by communities across the United States. While FPCs have grown in number considerably over the last decade, there remains a considerable lack of empirical research documenting evaluation and engagement methods, as well as strategies used to address community food security. This research, framed by the Community Coalition Action Theory, draws …

The Experiences Of African American Male Computer Science Majors In Two Year Colleges, Simone Brookins Jenkins

USF Tampa Graduate Theses and Dissertations

As the field of computer science grows and the computing science workforce demands more qualified workers, the United States workforce will require underrepresented minorities to help meet these demands. African American males are a demographic that can help meet this need but there are few of them pursuing computer science careers and successfully graduating with computer science degrees. The purpose of this qualitative study was to examine the experiences of African American male two-year college students who are in pursuit of a degree in computer science. My findings indicated that the study participants’ experiences such as positive interactions with faculty …