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Chemical Tools And Treatments For Neurological Disorders And Infectious Diseases, Andrea Lemus Nov 2019

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 Nov 2019

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 Nov 2019

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 …


Construction Of G-Quadruplexes Via Self-Assembly: Enhanced Stability And Unique Properties, Ying He Nov 2019

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+) …


The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki Nov 2019

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 …


Use Of Spectrofluorometry To Detect Petroleum Hydrocarbons In The Marine Environment, Mary Iris Abercrombie Nov 2019

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 …


Effect Of Atypical Protein Kinase C Inhibitor (Dnda) On Cell Proliferation And Migration Of Lung Cancer Cells, Raja Reddy Bommareddy Nov 2019

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) …


The Activity And Structure Of Cu2+-Biomolecules In Disease And Disease Treatment, Darrell Cole Cerrato Nov 2019

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. …


First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong Nov 2019

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, …


Biomimetic Light Harvesting In Metalloporphyrins Encapsulated/Incorporated Within Metal Organic Frameworks (Mofs)., Abdulaziz A. Alanazi Nov 2019

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 Nov 2019

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 Nov 2019

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 …


Untapped Potential Of Gorgonian Octocorals For Detecting Environmental Change In Biscayne National Park, Florida, Usa, Selena A. Kupfner Johnson Nov 2019

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 …


Past Climate And Sea-Level Reconstruction Using Cave Deposits From Mallorca, Spain, Oana-Alexandra Dumitru Nov 2019

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 Nov 2019

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 …


The Chemical Ecology And Drug Discovery Potential Of The Antarctic Red Alga Plocamium Cartilagineum And The Antarctic Sponge Dendrilla Membranosa, Andrew Jason Shilling Nov 2019

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 …


Design, Synthesis, And Self-Assembly Of Supramolecular Fractals Based On Terpyridine With Different Transition Metal Ions, Lei Wang Nov 2019

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 Adaptations Of The Sulfur-Oxidizing, Gammaproteobacterium "Candidatus Endoriftia Persephone", Endosymbiont Of The Giant Tubeworm Riftia Pachyptila, To Hydrothermal Vent Habitat Heterogeneity, Juliana M. Leonard Nov 2019

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 Nov 2019

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 Nov 2019

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 Nov 2019

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 …


Formulation To Application: Thermomechanical Characterization Of Flexible Polyimides And The Improvement Of Their Properties Via Chain Interaction, Alejandro Rivera Nicholls Nov 2019

Formulation To Application: Thermomechanical Characterization Of Flexible Polyimides And The Improvement Of Their Properties Via Chain Interaction, Alejandro Rivera Nicholls

USF Tampa Graduate Theses and Dissertations

In this work, Polyimides were synthesized by incorporating an aromatic diamine monomer with a methylene linker, 4,4'-methylenebis(2,6-dimethylaniline) (MBDMA), to make a robust main chain along with aliphatic polyetherdiamine backbone linkers to reduce rigidity. The polymers were designed to exhibit thermal properties in between those of conventional aromatic polyimides and polymers with wholly aliphatic ether diamine links. Through dynamic mechanical analysis and differential scanning calorimetry, it is shown that control of the molar ratios of the aromatic MBDMA and the composition and size of the aliphatic polyetherdiamine can be used to tune the glass transition temperature. The materials were characterized and …


Evaluating Conversation Agent Impact On Student Experience In A Distance Education Course, Grover Walters Nov 2019

Evaluating Conversation Agent Impact On Student Experience In A Distance Education Course, Grover Walters

USF Tampa Graduate Theses and Dissertations

We explore the efficacy of conversation agents operating as an instructional aid in a distance education course. Two aspects of efficacy are considered—conversation agent impact on student perceptions of the experience, and how different design features of the agent affect student perceptions of engagement. Evaluation of the agent is accomplished by collecting data from 24 undergraduate participants separated into random groups. We conduct two rounds of mixedmethod evaluation. Between the two rounds, a modification to the agent occurs based on the outcome of the first evaluation. Findings include limitations related to phrasing and data persistence features of the design that …


Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar Nov 2019

Effects Of Reservoir Conditions And Trace Co-Contaminant Gases On Geological Carbon Sequestration, Ram Kumar

USF Tampa Graduate Theses and Dissertations

Geological carbon sequestration in a saline formation is a promising technology for large-scale carbon dioxide (CO2) mitigation. Several factors such as temperature, pressure, salinity, hydraulic conductivity, and mineralogy of a formation affect the CO2 sequestration in saline formations. These factors can vary widely depending upon the type of formation or the degree of heterogeneity within a formation. In addition to these properties of the repositories, the CO2-rich flue gas streams captured from point sources often contains small amounts of impurities such as sulfur oxides (SOx) and nitrogen oxides (NOx), which may have serious implications on the chemistry of the repositories …


Measuring And Utilizing High-Dimensional Information Of Optical Fields, Ziyi Zhu Nov 2019

Measuring And Utilizing High-Dimensional Information Of Optical Fields, Ziyi Zhu

USF Tampa Graduate Theses and Dissertations

Currently, many areas of optical techniques including imaging, inspection and communication emphasize the utilization of the high-dimensional information encoded in optical fields. There is also a requirement for novel measurement techniques to extract this high-dimensional information with high-speed and accuracy. We firstly introduce a scan-free direct measurement technique that is capable of simultaneously characterizing the amplitude and phase of a coherent scalar optical field. Our direct measurement approach is constituted of a weak polarization perturbation which is followed by the recording of a polarization-resolving imaging process. The weak perturbation rotates the linear polarization on the spatial frequency domain of the …


Seafloor Geodesy In Shallow Water With Gps On An Anchored Spar Buoy, Surui Xie, Jason Law, Randy Russell, Timothy H. Dixon, Chad Lembke, Rocco Malservisi, Melanie Rodgers, Giovanni Iannaccone, Sergio Guardato, D. F. Naar Nov 2019

Seafloor Geodesy In Shallow Water With Gps On An Anchored Spar Buoy, Surui Xie, Jason Law, Randy Russell, Timothy H. Dixon, Chad Lembke, Rocco Malservisi, Melanie Rodgers, Giovanni Iannaccone, Sergio Guardato, D. F. Naar

School of Geosciences Faculty and Staff Publications

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 subduction zones and submerged volcanoes, and certain freshwater applications, such as volcano deformation in caldera‐hosted lakes. We have developed a seafloor geodesy 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 tracking data are used to recover …


Fractional Random Weighted Bootstrapping For Classification On Imbalanced Data With Ensemble Decision Tree Methods, Sean Charles Carter Nov 2019

Fractional Random Weighted Bootstrapping For Classification On Imbalanced Data With Ensemble Decision Tree Methods, Sean Charles Carter

USF Tampa Graduate Theses and Dissertations

Ensemble methods are commonly used for building predictive models for classification. Models that are unstable to perturbations in the training set, such as the decision tree, often see considerable reductions in error when grouped, using bootstrapped resamples of the training data to train many models. The non-parametric bootstrap, however, has limited efficacy when used on severely imbalanced data, especially when the number of observations of one or more classes is exceptionally small. We explore the fractional random weighted bootstrap, which randomly assigns fractional weights to observations, as an alternative resampling pro cedure in training machine learning ensembles, particularly decision tree …


Desertification Risk Analysis Based On Soils And Climate In Olive Cultivated Areas In Tulare County, California, Zehra Kavakli Karatas Nov 2019

Desertification Risk Analysis Based On Soils And Climate In Olive Cultivated Areas In Tulare County, California, Zehra Kavakli Karatas

USF Tampa Graduate Theses and Dissertations

Desertification is one of the most critical environmental problems caused by human activities and climate change. As a result of human activities, land degradation has been seen in many agricultural areas. Intense pressure on cultivated fields causes loss of soil fertility, which can then lead to desertification. Planting plant drought-resistant plants, such as olives, is one strategy for reducing desertification risk in cultivated areas. It is essential to find a way not only how to combat this process but also how to adapt or survive with desertification conditions. Defining desertification risks have a fundamental role in combating drought. The goal …


Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward Nov 2019

Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward

USF Tampa Graduate Theses and Dissertations

North of Martinique island the Lesser Antilles volcanic arc bifurcates, creating a double arc. Here volcanic activity has migrated up to 50 km westward with time, resulting in two volcanic lines that are distinct in age. The eastern line, commonly referred to as the old arc, was active from Early Eocene to Mid-Miocene (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., 1988). The western line, commonly referred to as the recent arc, has been active since the late Pliocene, ~6 Ma ago (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., …


Can Florida's Springs Coast Provide A Potential Refuge For Calcifying Organisms? Evidence From Benthic Foraminifera, Kyle E. Amergian Nov 2019

Can Florida's Springs Coast Provide A Potential Refuge For Calcifying Organisms? Evidence From Benthic Foraminifera, Kyle E. Amergian

USF Tampa Graduate Theses and Dissertations

Florida’s Springs Coast, located in the northeast Gulf of Mexico, includes an extensive system of salt marshes that discharge millions of liters of fresh water into coastal waters daily. The chemical properties of the spring waters include high alkalinity and high calcium concentrations due to the Paleogene limestone lithology of this region of Florida. Benthic foraminifers, which are recognized as ecologically important bioindicators, occur abundantly on the shallow shelf off the Springs Coast. Based on the prevalence of the benthic foraminifer Archaias angulatus in the seagrass beds along this shallow shelf, a previous study proposed that the Springs Coast provides …