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Stable Isotopes In The Eye Lenses Of Doryteuthis Plei: Exploring Natal Origins And Migratory Patterns In The Eastern Gulf Of Mexico, Brenna A. Meath

USF Tampa Graduate Theses and Dissertations

Stable isotope analysis is an emerging tool to examine trophic pathways and migratory patterns of marine organisms. Squid are widely distributed in coastal and deep water regions of the Gulf of Mexico. Stable isotope ratios of carbon and nitrogen found within cephalopod tissues can provide information on both trophic level and habitat of their food sources. More recently, ontogenetic changes in stable isotope ratios within squid eye lenses have been documented. Concentric layers of crystallin proteins are added to the lens as the squid ages; the center of the lens contains the oldest layer and the youngest layers are on …

Lung Ct Radiomics: An Overview Of Using Images As Data, Samuel Hunt Hawkins

USF Tampa Graduate Theses and Dissertations

Lung cancer is the leading cause of cancer-related death in the United States and worldwide. Early detection of lung cancer can help improve patient outcomes, and survival prediction can inform plans of treatment. By extracting quantitative features from computed tomography scans of lung cancer, predictive models can be built that can achieve both early detection and survival prediction. To build these predictive models, first a detected lung nodule is segmented, then image features are extracted, and finally a model can be built utilizing image features to make predictions. These predictions can help radiologists improve cancer care.

Building predictive models based …

Effects Of An Early Life Immune Challenge On Body Growth, Personality, Mating Behaviors, And Brain Development Of Zebra Finches (Taeniopygia Guttata), Ahmet Kerim Uysal

USF Tampa Graduate Theses and Dissertations

The developmental stress hypothesis predicts that an aversive condition, such as decreased food intake, predation, and social isolation, in the early developmental stage could have long term effects on behaviors and brain development of an animal. In nature, bird nestlings are susceptible to various factors, such as malnutrition, infections, and parasites. Effects of early life stress on adulthood have been extensively studied with some stressors including malnutrition. However, immune challenges as an early life stressor and their long-term programming effects on adult behaviors are yet to be studied in detail. The goal of the current study was to investigate changes …

Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin

USF Tampa Graduate Theses and Dissertations

Muscovy ducks are native only to Central and South America, Mexico, and parts of southern Texas and are considered invasive in some areas outside of their native range. Although they have been introduced worldwide, they remain largely unstudied. The primary focus of this study was to relate Muscovy duck abundance to habitat characteristics of wetlands in Tampa, Florida. Muscovy abundance was measured using point count methods at 21 wetland sites that occur within an eight km radius of the University of South Florida’s main campus. Habitat features at these sites were assessed using field methods and Geographic Information Systems (GIS) …

Zonation Pattern And Spatial Arrangement Of A Geukensia Granosissima Population In A Mixed Mangrove Forest Of Tampa Bay, Derrick Shane Hudson

USF Tampa Graduate Theses and Dissertations

Here I provide the first report on Geukensia granosissima patterns of abundance along a tidal gradient within a mixed mangrove stand located in Tampa Bay, Florida, USA. Specifically, I examined 1) the relationship between G. granosissima size and density with mangrove root type (e.g. prop root, pneumatophore), and of density within the intertidal zones; and 2) the possible role of predation in shaping the lower zonation patterns displayed. Transect surveys located along the lower and upper population limit boundaries were conducted every two months over a ten-month period. Variables measured include size distribution, density of mussels, above ground mangrove prop …

Geographical Information Systems (Gis) Applied To Urban Nutrient Management: Data Scarce Case Studies From Belize And Florida, Charlotte Juliane Haberstroh

USF Tampa Graduate Theses and Dissertations

Nutrient inputs into the environment greatly impact urban ecosystems. Appropriate management strategies are needed to limit eutrophication of surface water bodies and contamination of groundwater. In many existing urban environments, retrofits or complete upgrades are needed for stormwater and/or wastewater infrastructure to manage nutrients. However, sustainable urban nutrient management requires comprehensive baseline data that is often not available. A Framework for Urban Nutrient (FUN) Management for Geographic Information Systems (GIS) was developed to specifically address those areas with limited data access. Using spatial analysis in GIS, it links water quality, land use, and socio-demographics, thereby reducing data collection and field-based …

Evaluation Of Search And Rescue Planning Tools On The West Florida Shelf, Benjamin O'Loughlin

USF Tampa Graduate Theses and Dissertations

The Coast Guard conducts over 20,000 search and rescue cases a year with approximately 5% of them occurring within the coastal waters of the West Florida Shelf (WFS). Each search effort is planned using the Coast Guard’s Search and Rescue Optimal Planning System (SAROPS) which uses model inputs to create composite probability distributions based on the results of Monte Carlo projections of thousands of particle trajectories. However, SAROPS is limited by the quality of model inputs and their associated errors. This study utilizes observations from three surface drifter deployments on the WFS to evaluate the effectiveness of available surface current …

Molecular Response Of Spartina Alterniflora To The Deepwater Horizon Oil Spill, Mariano Alvarez

USF Tampa Graduate Theses and Dissertations

Although the “genome as a blueprint” metaphor has been pervasive in biology, recent advances in molecular biology have revealed a complex network of regulatory machinery that dynamically regulated molecular processes in response to environmental conditions. However, these patterns, as well as the evolutionary processes that underlie them, remain understudied in natural conditions. In 2010, the Deepwater Horizon oil spill released an estimated 4.9 million barrels of oil into the Gulf of Mexico, making landfall on salt marsh habitat dominated by the foundation species Spartina alterniflora. Despite the severe impacts to phenotype and fitness, S. alterniflora proved remarkably resilient in …

Development And Validation Of A Remote Sensing Model To Identify Anthropogenic Boreholes That Provide Dry Season, Refuge Habitat For Anopheles Vector Mosquitoes In Sub-Saharan Africa, James Pkemoi Kukat

USF Tampa Graduate Theses and Dissertations

A lack of surveillance systems is an impediment to public health intervention for perennial vector-borne disease transmission in northern tropical savanna region of Kenya. The population in this area are mostly poor nomadic pastoralists with little acquired functional immunity to Plasmodium falciparum, due to infrequent challenges with the parasite. A common characteristic in tropical savanna climatic zone is the availability of riverbeds that have anthropogenic boreholes that provide malaria vector mosquitoes, such as Anopheles gambiae s.l and Anopheles funestus, with aquatic refuge habitats for proliferation and endemic transmission to proximity human households during the dry-season. Unfortunately, currently there …

Quantifying The Association Between Active Tuberculosis Incidence And Migrant Farm Worker Populations Among Florida Counties, 2009-2013: An Ecological Study, Ryan Nicolas Ortega

USF Tampa Graduate Theses and Dissertations

Nearly 20 studies conducted in the last 40 years indicate that tuberculosis (TB) represents a major health concern among migrant farm worker (MFW) populations, but their role in the transmission of TB within the broader community is poorly understood. To this end an ecological study was undertaken which examined 67 Florida counties between years 2009 through 2013. Its aims were as follows: (1) to describe the demographic, geographic, and temporal distribution of the incidence of active TB, (2) to examine the effect of agriculturally relevant seasonal periods on the incidence of active TB, and (3) to quantify the strength and …

Chemical Investigation Of Antarctic Marine Organisms & Their Role In Modern Drug Discovery, Jacqueline Lee Fries

USF Tampa Graduate Theses and Dissertations

The chemicals produced by biological systems, whether proteins, peptides, or terpenes, will always provide an intriguing topic for researchers. Invisibly controlling every aspect of nature, these molecules are responsible for life, evolution, and death. Specifically, here is described the secondary metabolites produced by Antarctic marine organisms as well as others, and how they are used to defend or attract other animals while potentially providing health benefits to mankind. This is done through collection, extraction, and separation of individual specimens. The respective mixtures of compounds after isolation are then analyzed via spectroscopic methods such as nuclear magnetic resonance spectroscopy, mass spectrometry, …

Population Genetics And Epigenetics Of Two Salt Marsh Plant Species Along An Environmental Gradient, Christy M. Foust

USF Tampa Graduate Theses and Dissertations

Phenotypic plasticity is the ability of a given genotype to exhibit different phenotypes in response to environmental variables, which can impact population level processes. Plasticity of ecologically-relevant traits is important to an organism’s environmental response; however, the underlying mechanisms of plasticity are largely unknown. Ecological epigenetics may offer mechanisms (e.g. DNA methylation) underlying phenotypic plasticity. Epigenetics can be defined as the underlying molecular mechanisms that allow one genotype to exhibit different phenotypes. Differential DNA methylation is one epigenetic mechanism that has been correlated with a number of ecologically-relevant traits; including, differential herbivory in Viola cazorlensis, spinescence in Ilex aquifolium …

In Situ Studies Of Limestone Dissolution In A Coastal Submarine Spring, Rachel Marie Schweers

USF Tampa Graduate Theses and Dissertations

Limestone dissolution in karst environments is likely due to geochemistry of the water, the actions of microbial communities, and the effect of water flow. We explored the rate of limestone dissolution and will examine here the microbial communities associated with the limestone. A conduit within the brackish cave, Double Keyhole Spring, on the coast of central west Florida was the site of the experiment. PVC pipes (5cm x 16cm) were filled with crushed limestone that was screened to a 1.9cm – 2.54cm size range. There were three treatments (5 replicates each): Control - sealed autoclaved controls with limestone and conduit …

Evaluation Of Soil As A Risk Indicator For Human Leptospirosis In Coastal, Rural Ecuador, Chad Allen Weddell

USF Tampa Graduate Theses and Dissertations

Leptospirosis, a zoonotic disease caused by pathogenic spirochete bacteria (family Leptospiraceae, genus Leptospira), is endemic in developing tropical regions of the world. It occurs in epidemics and is endemic in Ecuador where environmental conditions are ideal for maintenance. The role of soil as a long term reservoir has been previously been documented. Geographic Information System (GIS) and Remote Sensing (RS) technology was used in our study to further explore the role of soil as an environmental reservoir and its potential use as a static risk indicator for disease. Red, Green, Blue (RGB) spectral band data from known leptospire …

Effect Of Timely Treatment On Malaria Gametocytemia In Esmeraldas, Ecuador, Miguel Reina-Ortiz

USF Tampa Graduate Theses and Dissertations

Malaria is a disease that causes great burden in public health worldwide. It was estimated that in 2011 there were 3.3 billion people at risk of acquiring malaria. According to data from the Ministry of Public Health of Ecuador, malaria incidence has shown a 99.9% steady decrease since year 2000. This study evaluated the effect of timely treatment on circulating gametocyte and malaria incidence rates. All cases reported in the province of Esmeraldas, Ecuador from July 2012 to March 2015 and to the national headquarters between February 2012 and December 2014 were studied. The effect of early treatment on: 1) …

Spatially-Weighted Ethnic Density And Residential Segregation: Effects On Health Status Among Older Mexican Americans, Sung Han Rhew

USF Tampa Graduate Theses and Dissertations

Research suggests that living in communities with high densities of persons from their own ethnic group improves the overall health of older Mexican Americans. One hypothesis is that residing in high ethnic density areas allows characteristics of Mexican culture such as strong social ties and social cohesion, to have a beneficial effect. The majority of investigations focused on ethnic density effects, however, have utilized relatively loose interpretations of what constitutes the appropriate social-geographic area to be studied. Moreover it is not clear how certain dimensions of residential segregation are protective or harmful toward health, particularly when measuring ethnic residential segregation …

Investigation Of Bioactive Metabolites From The Antarctic Sponge Dendrilla Membranosa And Marine Microorganisms, Chris G. Witowski

USF Tampa Graduate Theses and Dissertations

Natural products continue to be a valuable source of compounds in research involving chemical ecology and drug discovery. Secondary metabolites are biosynthesized to benefit the host organism in its environment (feeding deterrence from predators, antibiotic properties to avoid infection, etc.) but these compounds also serve as useful scaffolds in drug discovery applications. The research herein describes both aspects of these two branches of natural products chemistry. The Antarctic sponge Dendrilla membranosa produces diterpenes, of which membranolide A, deters feeding of the predatory amphipod Gondogenia antarctica. A metabolomic study of several sponges was undertaken to determine environmental factors that govern …

Historical And Current Population Patterns Of The Staghorn Coral (_Acropora Cervicornis_) In Dry Tortugas National Park, Kaitlyn Lizza

USF Tampa Graduate Theses and Dissertations

Acropora cervicornis was once one of the dominant reef building corals of the Caribbean, Florida Keys, and Dry Tortugas (DRTO), but since the 1970’s populations have been decimated throughout their geographic range. Recently, a repopulation was documented through detailed benthic surveys conducted by the U.S. Geological Survey at three locations (Pulaski Shoal, East Key, and Loggerhead Key) within DRTO. Benthic surveys using the U.S Geological Survey’s Along-Track Reef Imaging System (ATRIS) revealed hundreds of previously undocumented colonies.

These discoveries have provided a unique data-set, allowing a comparison between the historical (1883, 1976) and contemporary distributions (2009, 2011) of A. cervicornis. …

Short- And Long-Term Trends In Ecological Interactions: From Predator-Prey Interactions To Phanerozoic Diversification, Subhronil Mondal

USF Tampa Graduate Theses and Dissertations

During the last two decades, a broad spectrum of short- and long-term studies on different taxonomic groups has enriched our understanding about how dynamics of taxonomic and ecological diversification have changed through geologic time. There are two major issues that have impacted these studies: the quality and quantity of data used are often insufficient in various ways and the methods used may produce results that are more equivocal than supposed. To investigate these issues more fully, this dissertation focuses on studies on two major aspects: 1) short-term studies examining the nature of successful and unsuccessful predatory attacks on Plio-Pleistocene bivalves; …

Statistical Analysis And Modeling Of Pm2.5 Speciation Metals And Their Mixtures, Boubakari Ibrahimou

USF Tampa Graduate Theses and Dissertations

Exposure to fine particulate matter (PM_2.5) in the ambient air is associated with various health effects. There is increasing evidence which implicates the central role played by specific chemical components such as heavy metals of PM_2.5. Given the fact that humans are exposed to complex mixtures of environmental pollutants such as PM_2.5, research efforts are intensifying to study the mixtures composition and the emission sources of ambient PM, and the exposure-related health effects. Factor analysis as well source apportionment models are statistical tools potentially useful for characterizing mixtures in PM_2.5. However, classic …

A Multi-Scale Approach To Study Predator-Prey Interactions And Habitat Use Of Pinfish, Lagodon Rhomboids, Dinorah Helena Chacin

USF Tampa Graduate Theses and Dissertations

Biological processes like species interactions and patterns such as abundance and distribution observed in nature can vary depending on the scale at which the subject of interest is evaluated. Knowing that there is no single natural scale at which systems should be studied, in this thesis, I conducted a series of basic and applied ecological approaches in order to examine the phenomena that can occur at different scales of space, time, and ecological organization.

Species abundances can vary over large spatial and temporal scales. By studying the habitat use of an abundant species, which uses a wide range of habitats, …

Spatiotemporal Distribution Of Genus Culex (Diptera: Culicidae) In Usf Ecopreserve, Hillsborough County, Florida, Emily Schwartz

USF Tampa Graduate Theses and Dissertations

Within the state of Florida, there are three arboviruses of public health importance that can cause neuroinvasive disease in humans: West Nile Virus, Saint Louis Encephalitis Virus, and Eastern Equine Encephalitis Virus. Mosquitoes (Diptera: Culicidae) within the genus Culex are known and suspected vectors of these diseases. The vectors of these diseases can be present in urban wetland habitats that allow for exposure to residential communities. Vector ecology must be investigated in order to understand the dynamics of disease transmission. In Hillsborough County, Florida the spatial and temporal distribution of these vectors are not well established. An ecological study was …

Rurality And Intimate Partner Homicide: Exploring The Relationship Between Place, Social Structure, And Femicide In North Carolina, Amelia Kirkland

USF Tampa Graduate Theses and Dissertations

A developing body of research within the fields of criminology and rural sociology has emphasized the importance of considering geographic place in the study of interpersonal violence, and domestic violence in particular. Exploring how place is related to domestic violence lends itself to considerations of geographic variation in socio-structural conditions. A handful of studies since the 1980s have explored structural correlates of intimate abuse largely rooted in one of two theoretical contexts: social disorganization or gender inequality/patriarchy. However, knowledge regarding the relationship between place, social structure, and specific types of violence remains limited. The present study is intended as an …

Assessing The Relationship Between Hotspots Of Lead And Hotspots Of Crime, Kimberly L. Barrett

USF Tampa Graduate Theses and Dissertations

Numerous medical and environmental toxicology studies have established a link between lead (Pb) exposure, crime, and delinquency. In human environments, lead pollution- like crime- is unequally distributed, creating lead hot spots. In spite of this, studies of crime hotspots have routinely focused on traditional sociological predictors of crime, leaving environmental predictors of crime like lead and other neurotoxins relatively unaddressed. This study attends to this gap in the literature by asking a very straightforward research question: Is there a relationship between hotspots of lead and hotspots of crime? Furthermore, what is the nature and extent of this relationship? Lastly, is …

Gradients In Season, Latitude, And Sea Ice: Their Effect On Metabolism And Stable Isotopic Composition Of Antarctic Micronekton, Erica H. Ombres

USF Tampa Graduate Theses and Dissertations

Respiration, metabolic enzyme assays, and body composition parameters were measured in the Antarctic krill Euphausia superba during the summer, fall and winter on the Western Antarctic Peninsula (WAP). E. superba of all sizes decrease their metabolism from the summer to the winter. These same parameters were also measured along the WAP during the austral fall 2010. E. superba's enzyme activity indicated that there was a latitudinal gradient to the decline in metabolism along the WAP with the more northerly sites having significantly higher metabolic enzyme activities than the sites to the south.

Carbon (δ¹³C) and nitrogen (δ^{15 …}

Eco-Epidemiology Of Eastern Equine Encephalitis Virus, Patrick Vander Kelen

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Eastern Equine Encephalitis virus (EEEV) is an alphavirus with high pathogenicity in both humans and horses. Florida continues to have the highest occurrence of human cases in the USA, with four fatalities recorded in 2010. Unlike other states, Florida supports year-round EEEV transmission. This research uses Geographic Information Science (GIS) to examine spatial patterns of documented sentinel seroconversions and horse cases in order to understand the relationships between habitat and transmission intensity of EEEV in Florida. Sentinel sites were categorized as enzootic, periodically enzootic, and negative based on the amount of chicken seroconversions to EEEV. Sentinel sites were analyzed …

An Investigation Of The Factors Leading To Invasion Success Of Non-Native Plants Using A System Of Native, Introduced Non-Invasive, And Invasive Eugenia Congeners In Florida, Kerry Bohl

USF Tampa Graduate Theses and Dissertations

The overwhelming majority of plant species introduced into a new range never become invasive. Consequently, identification of factors allowing the small fraction of successful invaders to naturalize, increase in abundance, and displace resident species continues to be a key area of research in invasion biology. Of the considerable number of hypotheses that have been proposed to resolve why some plant species become noxious pests, the enemy release hypothesis (ERH) is one of the most commonly cited. The ERH maintains that invasive plants succeed in a new range because they are no longer regulated by their coevolved natural enemies, and this …

Ecology Of The Late Neogene Extinctions: Perspectives From The Plio-Pleistocene Of Florida, Shubhabrata Paul

USF Tampa Graduate Theses and Dissertations

The ecological impact of past extinction events is one of the central issues in paleobiology. In face of present environmental changes, a better understanding of past extinctions will enable us to identify the magnitude of biodiversity crises and their underlying processes. The Late Neogene was a time of extraordinary climatic reorganization, including Northern Hemisphere glaciation, the rise of the Central American Isthmus, and associated changes in environmental conditions. Therefore, the Late Neogene extinctions of marine molluscs of South Florida present an ideal platform to examine the interaction between environmental changes and biotic response. In the present study, three different aspects …

Associational Resistance And Competition In The Asphondylia - Borrichia - Iva System, Keith Stokes

USF Tampa Graduate Theses and Dissertations

Indirect ecological effects such as associational resistance and resource competition have the potential to affect ecological interactions and influence the structure of ecological communities. Although resource competition is commonly studied, the effects of associational resistance are not as evident if studies are not designed to detect them. Additionally, the relative strengths of different ecological mechanisms ought to be measured in studies, rather than the strength of singular mechanisms. This permits proper attribution of causes and effects in community structure and detection of higher order interactions in a way that naïve reductionism will not.

In a series of experiments, I looked …

Investigations For Utilizing Pteropods As Bioindicators Of Environmental Change Along The Western Antarctic Peninsula, Paul Mark Suprenand

USF Tampa Graduate Theses and Dissertations

Pteropods are holoplanktonic gastropod molluscs found globally. Although species diversity is greater at lower latitudes, species abundance is greater at temperate and polar latitudes. Declines in pteropod populations have not only been correlated to declines of their major predators, but pteropods have also been used as bioindicators of global environmental changes such as ocean acidification. With high latitude abundances, pteropods provide significant sustenance for species such as the Atlantic salmon in the Atlantic Ocean and Pleuragramma antarcticum in the Southern Ocean. Because pteropods eat phytoplankton and other pteropods, factors that affect pteropod abundance influence many trophic levels. This dissertation explores …