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Articles 1921 - 1950 of 2279

Full-Text Articles in Life Sciences

Enso-Correlated Fluctuations In Ocean Bottom Pressure And Wind-Stress Curl In The North Pacific, D. P. Chambers Jan 2011

Enso-Correlated Fluctuations In Ocean Bottom Pressure And Wind-Stress Curl In The North Pacific, D. P. Chambers

Marine Science Faculty Publications

We examine the output of an ocean model forced by ECMWF winds to study the theoretical relationship between wind-induced changes in ocean bottom pressure in the North Pacific between 1992 until 2010 and ENSO. Our analysis indicates that while there are significant fluctuations correlated with some El Niño and La Niña events, the correlation is still relatively low. Moreover, the ENSO-correlated variability explains only 50 % of the non-seasonal, low-frequency variance. There are significant residual fluctuations in both wind-stress curl and ocean bottom pressure in the region with periods of 4-years and longer. One such fluctuation began in late 2002 …


Sea Surface Temperature Variability In The Florida Keys And Its Relationship To Coral Cover, I. M. Soto, Frank E. Muller-Karger, Pamela Hallock, C. Hu Jan 2011

Sea Surface Temperature Variability In The Florida Keys And Its Relationship To Coral Cover, I. M. Soto, Frank E. Muller-Karger, Pamela Hallock, C. Hu

Marine Science Faculty Publications

The hypothesis that moderate variability in Sea Surface Temperature (SST) is associated with higher coral cover and slower rates of decline of coral cover within the Florida Keys National Marine Sanctuary (FKNMS) was examined. Synoptic SST time series covering the period 1994–2008 were constructed for the FKNMS with the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer satellite sensors. The SST data were compared with coral-cover time-series data from 36 sites monitored by the Coral Reef and Evaluation Monitoring Program. Sites that experienced moderately high SST variability relative to other sites showed a trend toward higher percentage coral …


Using A Focus Measure To Automate The Location Of Biological Tissue Surfaces In Brightfield Microscopy, Daniel Toby Elozory Jan 2011

Using A Focus Measure To Automate The Location Of Biological Tissue Surfaces In Brightfield Microscopy, Daniel Toby Elozory

USF Tampa Graduate Theses and Dissertations

The study of microstructures in brightfield microscopy using unbiased stereology plays a large and growing role in bioscience research. Stereology enables objective quantitative analysis of biological structures within a tissue sample. A first step in the stereology process is to calculate the thickness of a tissue sample by locating the top and bottom surfaces of the sample. The aim of this project is to fully automate this location process by using the relative optical focus measure as an indicator of tissue surface boundary.

The current method for identification of focus bounding planes requires a trained user to manually select the …


Identification And Characterization Of The Human Herpesviruses 6a And 6b Genome Integration Into Telomeres Of Human Chromosomes During Latency, Jesse Herbert Arbuckle Jan 2011

Identification And Characterization Of The Human Herpesviruses 6a And 6b Genome Integration Into Telomeres Of Human Chromosomes During Latency, Jesse Herbert Arbuckle

USF Tampa Graduate Theses and Dissertations

While the latent genome of most Herpesviruses persists as a nuclear circular episome, previous research has suggested that Human Herpesvirus 6 (HHV-6) may integrate into host cell chromosomes, and be vertically transmitted in the germ-line. Because the HHV-6 genome encodes a perfect TTAGGG telomere repeat array at the right end direct repeat (DRR) and an imperfect TTAGGG repeat at the end of the left end direct repeat (DRL), we established a hypothesis that during latency, the HHV-6A and HHV-6B genome integrates into the telomeres of human chromosomes through homologous recombination with the n(TTAGGG) viral repeats, and …


Development Of An Elisa For Eastern Equine Encephalitis Virus That Can Differentiate Infected From Vaccinated Horses, Andrea Bingham Jan 2011

Development Of An Elisa For Eastern Equine Encephalitis Virus That Can Differentiate Infected From Vaccinated Horses, Andrea Bingham

USF Tampa Graduate Theses and Dissertations

Eastern Equine Encephalitis virus (EEEV) causes a fatal mosquito-borne virus that is vaccine preventable for horses. The conventional serological tests measure antibodies to the structural proteins of EEEV which are also found in the vaccine. This makes it difficult to differentiate infected and vaccinated animals (DIVA). Detection of antibodies to non-structural proteins (NSPs) is a theoretical strategy that would allow you to survey natural infections among vaccinated populations. This test would also allow for more accurate representations of the natural infection rate, vaccination rate, and help identify vaccine failures. The potential uses of the NSPs of Eastern Equine Encephalitis virus …


A Comparative Study Of Eucalanoid Copepods Residing In Different Oxygen Environments In The Eastern Tropical North Pacific: An Emphasis On Physiology And Biochemistry, Christine J. Cass Jan 2011

A Comparative Study Of Eucalanoid Copepods Residing In Different Oxygen Environments In The Eastern Tropical North Pacific: An Emphasis On Physiology And Biochemistry, Christine J. Cass

USF Tampa Graduate Theses and Dissertations

The eastern tropical north Pacific (ETNP) is characterized by one of the ocean's most severe midwater oxygen minimum zones (OMZs), where oxygen levels are often less than 5 µM. The copepod family Eucalanidae is a numerically abundant and diverse zooplankton group in the ETNP, and displays a wide range of vertical distributions related to environmental oxygen concentrations. The goal of this dissertation was to develop a better understanding of the ecology, physiology, and biochemistry of closely related copepod species (family Eucalanidae) that inhabit the ETNP OMZ system. This was accomplished through examining different parameters relating to (1) metabolic rates, (2) …


Lead Discovery And Optimization Strategies Towards The Development Of 4(1h)-Quinolones And 1,2,3,4-Tetrahydroacridone Analogs With Antimalarial Activity, Richard Matthew Cross Jan 2011

Lead Discovery And Optimization Strategies Towards The Development Of 4(1h)-Quinolones And 1,2,3,4-Tetrahydroacridone Analogs With Antimalarial Activity, Richard Matthew Cross

USF Tampa Graduate Theses and Dissertations

The goal of our research endeavor was to successfully employ modern lead discovery and optimization strategies towards the development and identification of compounds possessing antimalarial activity. Preliminary data from in vitro screening at the Walter Reed Army Institute of Research identified several chemotypes including 4(1H)-quinolones and 1,2,3,4-tetrahydroacridones to have potent antimalarial activities. Multiple synthetic routes were devised and implemented which enabled the rapid preparation and isolation of over 400 structurally diverse 4(1H)-quinolones and 1,2,3,4-tetrahydroacridones.

Our research towards discovering and optimizing antimalarials was inspired from the severe impact malaria has had on our planet especially on impoverished countries. There are over …


Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple Jan 2011

Mechanistic Modeling Of Photocatalytic Water Disinfection, Omatoyo Kofi Dalrymple

USF Tampa Graduate Theses and Dissertations

The main goal of this research was to develop a mechanism-based model for photocatalytic disinfection of bacteria in water using suspended catalyst pthesiss in batch reactors. The photocatalytic disinfection process occurs as a semiconductor photocatalyst, most commonly titanium dioxide (TiO2), is irradiated with light of wavelength less than 380 nm to produce hydroxyl radicals and other highly reactive oxidants which can inactivate microorganisms. Photocatalytic disinfection involves a complex interaction of many fundamental mechanisms such as light absorption and scattering by semiconductor pthesiss, electrochemical surface reactions, and heterogeneous colloidal stability. Current models, based largely on chemical reacting systems, do …


Role Of Protein Kinase C-Iota In Glioblastoma, Shraddha R. Desai Jan 2011

Role Of Protein Kinase C-Iota In Glioblastoma, Shraddha R. Desai

USF Tampa Graduate Theses and Dissertations

The focus of this research was to investigate the role of protein kinase C-iota (PKC-é) in the regulation of Bad function, a pro-apoptotic member of the Bcl-2 family and Cdk7 function, a master cell cycle regulator in glioblastoma.

The results were obtained from the human glial tumor derived cell lines, T98G and U87MG. In these cells, PKC-é co-localized and directly associated with Bad as shown by immunofluorescence, immunoprecipitation, and Western blotting. Furthermore, in-vitro kinase activity assay showed that PKC-é directly phosphorylated Bad at phospho specific residues, S112, S136 and S155 which in turn induced inactivation of Bad and disruption of …


Population Genetics Of Amphiuma Means And Siren Lacertina In Central Florida, Anna C. Deyle Jan 2011

Population Genetics Of Amphiuma Means And Siren Lacertina In Central Florida, Anna C. Deyle

USF Tampa Graduate Theses and Dissertations

Population structure can be defined as a difference in the frequencies of alleles among populations, and it is often caused by barriers to dispersal. I used mitochondrial DNA sequences to examine the population structure of two large, aquatic salamanders, Amphiuma means (the Two-Toed Amphiuma) and Siren lacertina (the Greater Siren), at two spatial scales in peninsular Florida. Both species appear to have similar life histories, including poor dry land dispersal capabilities, and I hypothesized that they would exhibit significant population structure at both broad and fine scales. Wetland loss and landscape fragmentation are certain to have caused decreases in abundance …


Regulation Of Cell Adhesion Strength By Spatial Organization Of Focal Adhesions, Kranthi Kumar Elineni Jan 2011

Regulation Of Cell Adhesion Strength By Spatial Organization Of Focal Adhesions, Kranthi Kumar Elineni

USF Tampa Graduate Theses and Dissertations

Cell adhesion to extracellular matrix (ECM) is critical to various cellular processes like cell spreading, migration, growth and apoptosis. At the tissue level, cell adhesion is important in the pathological and physiological processes that regulate the tissue morphogenesis. Cell adhesion to the ECM is primarily mediated by the integrin family of receptors. The receptors that are recruited to the surface are reinforced by structural and signaling proteins at the adhesive sites forming focal adhesions that connect the cytoskeleton to further stabilize the adhesions. The functional roles of these focal adhesions extend beyond stabilizing adhesions and transduce mechanical signals at the …


Multivariate Anti-Inflammatory Approaches To Rescue Neurogenesis And Cognitive Function In Aged Animals, Sandra Antonieta Acosta Jan 2011

Multivariate Anti-Inflammatory Approaches To Rescue Neurogenesis And Cognitive Function In Aged Animals, Sandra Antonieta Acosta

USF Tampa Graduate Theses and Dissertations

Studies have shown that there is a strong correlation between aging and neurodegenerative diseases. Aging is considered the number one risk factor to develop neuropathologies such as memory loss, senile dementia, Alzheimer's disease (AD), and Parkinson's disease. Neurodegenerative diseases tend to start during adulthood, and aggravate over time, making them difficult to prevent and to treat. In the Unites States, demographic studies by U.S. Bureau of the Census have determined that our aging population of >65 years is expected to increase from the present 35 million to 78 million in 2030. This would result, not only to an increase of …


The Effect Of Various Carbohydrate Supplements On Postprandial Blood Glucose Response In Female Soccer Players, Nina Pannoni Jan 2011

The Effect Of Various Carbohydrate Supplements On Postprandial Blood Glucose Response In Female Soccer Players, Nina Pannoni

USF Tampa Graduate Theses and Dissertations

PURPOSE: The purpose of this study is to examine the effects of different types of carbohydrates on blood glucose response in collegiate soccer athletes at rest. This will help to determine the effectiveness of a carbohydrate supplement in providing sustained energy and maintained performance if ingested prior to a soccer match. METHODS: In a cross-over design, 10 female collegiate soccer players (n= 10, age 20.10 ± .99 years, height 65.55 ± 2.77 inches, weight 64.12 ± 8.36 kilograms) from the University of South Florida reported to the laboratory on five separate occasions after an overnight fast. Once a baseline blood …


Secreted Factors From Human Umbilical Cord Blood Cells Protect Oligodendrocytes From Ischemic Insult, Derrick Rowe Jan 2011

Secreted Factors From Human Umbilical Cord Blood Cells Protect Oligodendrocytes From Ischemic Insult, Derrick Rowe

USF Tampa Graduate Theses and Dissertations

Oligodendrocytes (OL)s are the dominant cell type in the white matter and are integral for synaptic transmission essential for proper neuronal communication between brain areas. Previous studies have shown that intravenous administration of the mononuclear fraction of human umbilical cord blood (HUCB) cells in rat models of stroke reduced white matter injury, gray matter injury and behavioral deficits. Yet the mechanisms used by HUCB cells remain unknown in ischemic injury. These studies will investigate both in vitro and in vivo approaches to elucidate this mechanism in OLs. When mature primary OLs were coincubated with HUCB cells, HUCB cells secreted soluble …


Estimating Groundwater Discharge In The Oligohaline Ecotone Of The Everglades Using Temperature As A Tracer And Variable-Density Groundwater Models, Victora Spence Jan 2011

Estimating Groundwater Discharge In The Oligohaline Ecotone Of The Everglades Using Temperature As A Tracer And Variable-Density Groundwater Models, Victora Spence

USF Tampa Graduate Theses and Dissertations

Recent research suggests that brackish, marine-derived groundwater up-wells in the oligohaline ecotone of the coastal Everglades, bringing with it phosphorus to an otherwise phosphorus-poor environment. The purpose of this study is to estimate the rates and timing of the groundwater discharge by using variable-density groundwater models constructed, calibrated, and validated with field measurements of hydraulic head and surface and subsurface temperature. Modeled groundwater discharge rates ranged from 5.4E-04 mm/day in August to -1.3E-03 mm/day in June for Shark Slough and 4.8E-01 mm/day in June to -1.4E-01 mm/day in January for Taylor Slough, where positive values imply groundwater discharge and negative …


The Role Of Brca1 Domains And Motifs In Tumor Suppression, Aneliya Velkova Jan 2011

The Role Of Brca1 Domains And Motifs In Tumor Suppression, Aneliya Velkova

USF Tampa Graduate Theses and Dissertations

Individuals that carry deleterious mutations in the breast and ovarian cancer susceptibility gene 1 (BRCA1) have much more elevated risk to develop breast and/or ovarian cancer than the individuals from the general population. The BRCA1 gene product has been implicated in several aspects of the DNA damage response, but its biochemical function in these processes has remained elusive. In order to probe BRCA1 functions we conducted a yeast two-hybrid screening to identify interacting partners to a conserved motif (Motif 6) in the central region of BRCA1. In this dissertation, we report the identification of the actin-binding protein Filamin A (FLNA) …


From Dna To Protein: A Study Of Genomic Instability Candidate Genes During Zebrafish Development, Kristine Griffett Jan 2011

From Dna To Protein: A Study Of Genomic Instability Candidate Genes During Zebrafish Development, Kristine Griffett

USF Tampa Graduate Theses and Dissertations

The zebrafish, Danio rerio, is a type of freshwater minnow often used to model human diseases including cancer, anxiety and aging diseases. The overall biology of zebrafish is strikingly similar to that of humans, allowing these fish to be used for drug discovery and toxicology studies for preclinical trials. In this study, zebrafish embryos were used to identify and characterize several candidate genes within two known regions of genomic instability on chromosome 18 and chromosome 4. This fish that were used in this study had been previously classified as genomic instability (gin) mutants due to increased incidence of somatic mutation …


Relative Abundance And Spatial Distribution Of Lepomid Sunfishes In The Peace River, Justin Henry Heller Jan 2011

Relative Abundance And Spatial Distribution Of Lepomid Sunfishes In The Peace River, Justin Henry Heller

USF Tampa Graduate Theses and Dissertations

This study examines spatially continuous sampling data in order to investigate patterns of abundance and distribution of three recreationally important sunfish species (bluegill, redear, and spotted sunfish) along the main-stem of the Peace River, a large softwater river located in southwest Florida. A total of 467 electrofishing transects were sampled biannually from spring 2008 to spring 2010. Sampling sites ranged from the headwaters of the Peace River in Polk County, FL to the oligohaline waters located in Charlotte County, FL. All fish were collected with boat mounted electrofishing gear, and aquatic habitat and physiochemical water quality measurements were recorded at …


Evaluating The Effects Of Beach Nourishment On Loggerhead Sea Turtle (Caretta Caretta) Nesting In Pinellas County, Florida, Corey R. Leonard Ozan Jan 2011

Evaluating The Effects Of Beach Nourishment On Loggerhead Sea Turtle (Caretta Caretta) Nesting In Pinellas County, Florida, Corey R. Leonard Ozan

USF Tampa Graduate Theses and Dissertations

The health of Florida's beaches are vital to the survival of loggerhead sea turtles (Caretta caretta), as nearly half of the world's loggerheads nest on the states beaches. Many of the beaches utilized by the turtles have undergone nourishment projects in hopes of combating erosion of the shoreline, protecting beachfront property, and creating more suitable beaches for tourism. Although it is argued that beach nourishment benefits sea turtles by providing more nesting habitat, the effects of the Pinellas County nourishment projects on loggerhead nesting are unknown. Beach nourishment can alter the compaction, moisture content, and temperature of the sand, all …


The Roles Of Elevated Bcl-2 In Ovarian Cancer, Nicole Shree Anderson Dec 2010

The Roles Of Elevated Bcl-2 In Ovarian Cancer, Nicole Shree Anderson

USF Tampa Graduate Theses and Dissertations

Ovarian cancer (OC) is the second most common gynecologic cancer; however it is responsible for the most gynecologic cancer-related deaths. Apoptosis evasion is an important mechanism in OC tumorigenesis, and the prototypic anti-apoptotic protein, B-cell lymphoma 2 (Bcl-2), is often overexpressed in OC tumors. Gaining a better understanding of the mechanism(s) behind Bcl-2 overexpression and potential extra-anti-apoptotic functions of Bcl-2 could elucidate the importance of elevated Bcl-2 in OC. In the current study, I show through immunohistochemical analysis of normal, benign, and OC tissue sections, that both epithelial and stromal Bcl-2 expression decreases with OC progression. However, the number of …


Deglacial Abrupt Climate Change In The Atlantic Warm Pool: A Gulf Of Mexico Perspective, Carlie Williams, Benjamin P. Flower, David W. Hastings, Thomas P. Guilderson, Kelly A. Quinn, Ethan A. Goddard Dec 2010

Deglacial Abrupt Climate Change In The Atlantic Warm Pool: A Gulf Of Mexico Perspective, Carlie Williams, Benjamin P. Flower, David W. Hastings, Thomas P. Guilderson, Kelly A. Quinn, Ethan A. Goddard

Marine Science Faculty Publications

During the last deglaciation, Greenland ice core and North Atlantic sediment records exhibit multiple abrupt climate events including the Younger Dryas cold episode (12.9-11.7 ka). However, evidence for the presence of the Younger Dryas in the Gulf of Mexico (GOM) and the relationship between GOM sea surface temperature (SST) and high-latitude climate change is less clear. We present new Mg/Ca-SST records from two varieties of the planktonic foraminifer Globigerinoides ruber (white and pink) to assess northern GOM SST history from approximately 18.4-10.8 ka. Thirty-five accelerator mass spectrometry (AMS) C-14 dates from Orca Basin core MD02-2550 provide excellent age control and …


A Half-Century Of Changes In China's Lakes: Global Warming Or Human Influence?, Ronghua Ma, Hongtao Duan, Chuanmin Hu, Xuezhi Feng, Ainong Li, Weimin Ju, Jiahu Jiang, Guishan Yang Dec 2010

A Half-Century Of Changes In China's Lakes: Global Warming Or Human Influence?, Ronghua Ma, Hongtao Duan, Chuanmin Hu, Xuezhi Feng, Ainong Li, Weimin Ju, Jiahu Jiang, Guishan Yang

Marine Science Faculty Publications

Lake size is sensitive to both climate change and human activities, and therefore serves as an excellent indicator to assess environmental changes. Using a large volume of various datasets, we provide a first complete picture of changes in China's lakes between 1960s–1980s and 2005–2006. Dramatic changes are found in both lake number and lake size; of these, 243 lakes vanished mainly in the northern provinces (and autonomous regions) and also in some southern provinces while 60 new lakes appeared mainly on the Tibetan Plateau and neighboring provinces. Limited evidence suggested that these geographically unbalanced changes might be associated primarily with …


Ocean Mass From Grace And Glacial Isostatic Adjustment, D. Chambers, John Wahr, Mark E. Tamisea, R Steven Nerem Nov 2010

Ocean Mass From Grace And Glacial Isostatic Adjustment, D. Chambers, John Wahr, Mark E. Tamisea, R Steven Nerem

Marine Science Faculty Publications

We examine geoid rates and ocean mass corrections from two published global glacial isostatic adjustment (GIA) models, both of which have been used in previous studies to estimate ocean mass trends from Gravity Recovery and Climate Experiment (GRACE) satellite gravity data. These two models are different implementations of the same ice loading history and use similar mantle viscosity profiles. The model results are compared with each other and with geoid rates determined from GRACE during August 2002 to November 2009. When averaged over the global ocean, the two models have rates that differ by nearly 1 mm yr−1 of …


Evaluation Of Immunogene Therapy Using A Plasmid Encoding Il-15 Delivered By Electroporation In A 3d Tumor Model And A Mouse Melanoma Model, Bernadette Marrero Nov 2010

Evaluation Of Immunogene Therapy Using A Plasmid Encoding Il-15 Delivered By Electroporation In A 3d Tumor Model And A Mouse Melanoma Model, Bernadette Marrero

USF Tampa Graduate Theses and Dissertations

Melanoma is an aggressive disease with few effective treatment options. Non-toxic, anti-tumor therapies and prophylactic approaches are currently being investigated to identify treatment options that will control and remove late-stage melanoma.

The overall goal of this project was to establish an effective delivery method for a plasmid encoding human interleukin (phIL-15) into mouse melanoma cells (B16.F10) using the gene transfer technique electroporation (EP)1. The EP delivery phIL-15 was optimized using an in vitro 3D tumor model. The purpose was to translate these IL-15 delivery conditions into an in vivo mouse melanoma model to study IL-15 signal transduction and …


Characterization Of The Role Of Nicotine And Delta 9-Thc In Modulation Of Neuroinflammation, Jared C. Ehrhart Oct 2010

Characterization Of The Role Of Nicotine And Delta 9-Thc In Modulation Of Neuroinflammation, Jared C. Ehrhart

USF Tampa Graduate Theses and Dissertations

Neuroinflammation is a major driving force in the progression of neurodegenerative disorders. Nicotinic acetylcholine receptors, as well as cannabinoid CB2 receptors, have been shown to have strong anti-inflammatory properties when activated. These effects are shown, in vivo, to be a result of stimulation of α7 nAChRs and CB2 cannabinoid receptors. Microglia cells, an immune cell in the brain, are shown to express both of these receptor subtypes. The studies detailed herein, investigated the ability of two compounds, nicotine and Δ9-THC, in modulation of inflammatory processes. Stimulation of these receptors on microglia using nicotine and Δ9-THC blocked the activation of these …


Molecular Mechanism Of Agc Kinases In Human Malignant, Shaokun Shu Oct 2010

Molecular Mechanism Of Agc Kinases In Human Malignant, Shaokun Shu

USF Tampa Graduate Theses and Dissertations

The maintenance of normal cell function and tissue homeostasis is dependent on the precise regulation of multiple signaling pathways that control cellular decisions to either proliferate, differentiate, arrest cell growth, or initiate programmed cell death (apoptosis). Cancer arises when clones of mutated cells escape this balance and proliferate inappropriately without compensatory apoptosis. Deregulated cell growth occurs as a result of perturbed signal transduction that modulates or alters cellular behavior or function to keep the critical balance between the rate of cell-cycle progression (cell division) and cell growth (cell mass) on one hand, and programmed cell death (apoptosis, autophagy) on the …


The Human In 3d: Advanced Morphometric Analysis Of High-Resolution Anatomically Accurate Computed Models, Summer J. Decker Oct 2010

The Human In 3d: Advanced Morphometric Analysis Of High-Resolution Anatomically Accurate Computed Models, Summer J. Decker

USF Tampa Graduate Theses and Dissertations

Computed virtual models of anatomical structures are proving to be of increasing value in clinical medicine, education and research. With a variety of fields focused on craniofacial and pelvic anatomy there is a need for accurate anatomical models. Recent technological advancements in computer and medical imaging technologies have provided the tools necessary to develop three-dimensional (3D) functional models of human anatomy for use in medicine (surgical planning and education), forensics and engineering (computer-aided design (CAD) and finite element analysis).

Traditionally caliper methodologies are used in the quantitative analysis of human anatomy. In order for experts in anatomy and morphometrics to …


The Biogeochemistry Of Submerged Coastal Karst Features In West Central Florida, Keith Michael Garman Sep 2010

The Biogeochemistry Of Submerged Coastal Karst Features In West Central Florida, Keith Michael Garman

USF Tampa Graduate Theses and Dissertations

West Central Florida is a complex karst environment with numerous sinkholes, springs, and submerged cave systems. Many of these karst features are anchialine, located within the subterranean estuary where freshwater and saltwater mix. Water quality data and/or fauna data were obtained from twenty-one karst features and their associated cave systems. The anchialine karst environment of the study area has a wide range of habitats with measured salinities ranging from freshwater at <0.2 ppt to sulfidic, hypersaline water at 38.5 ppt and measured pH readings ranging from 6.39 in water impacted by sulfur oxidizing bacteria to 10.3 in an isolated room of a cave. Stygobitic crustaceans were identified in conduits extending beneath the Gulf of Mexico supporting the hypotheses that freshwater crustaceans could survive higher sea levels in freshwater conduits beneath saltwater. The fauna associated with the anchialine cave systems included Sabellidae and Polychaeta worms, hydroids, cnidarians and hydrobiid snails. Jewfish Sink, like other anaerobic marine basins that were submarine springs, has four zones: oxic zone, transition zone, upper anoxic zone and anoxic bottom water. The upper zones have seasonal water quality variations from winter cooling and sinking of surface water and changes in the microbial communities. Activity of sulfate reducing bacteria is carbon limited in the anoxic zones, where sulfate reduction is the major metabolic process, and primary production is phosphate limited in the oxic zones. Organic input from the Gulf of Mexico drives the bacterial anaerobic ecosystem, resulting in a “sulfide pump”, in which sulfide percolates upward removing oxygen from the overlying sediment.


Time Series Of Bio-Optical Properties In A Subtropical Gyre: Implications For The Evaluation Of Interannual Trends Of Biogeochemical Properties, Zhongping Lee, Shaoling Shang, Chuanmin Hu, Marlon Lewis, Robert Arnone, Yonghong Li, Bertrand Lubac Sep 2010

Time Series Of Bio-Optical Properties In A Subtropical Gyre: Implications For The Evaluation Of Interannual Trends Of Biogeochemical Properties, Zhongping Lee, Shaoling Shang, Chuanmin Hu, Marlon Lewis, Robert Arnone, Yonghong Li, Bertrand Lubac

Marine Science Faculty Publications

With a validated Quasi‐Analytical Algorithm, an 11 year (1998–2008) monthly time series of the primary optical properties of waters in the center of the South Pacific gyre was developed from Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer (MODIS). Also derived are chlorophyll a (Chl a) concentrations with the operational empirical algorithms for SeaWiFS and MODIS. The optical properties include the absorption coefficient (at 443 nm) of phytoplankton (aph) and that of the combination of detritus and gelbstoff (adg). From these time series, we further derived their annual background (summer low) …


Discrimination Of Human And Non-Human Sources Of Pollution In Gulf Of Mexico Waters By Microbial Source Tracking Methods And The Investigation Of The Influence Of Environmental Factors On Escherichia Coli Survival, Asja Korajkic Aug 2010

Discrimination Of Human And Non-Human Sources Of Pollution In Gulf Of Mexico Waters By Microbial Source Tracking Methods And The Investigation Of The Influence Of Environmental Factors On Escherichia Coli Survival, Asja Korajkic

USF Tampa Graduate Theses and Dissertations

Water quality worldwide is assessed by enumeration of fecal indicator bacteria (FIB) (fecal coliforms, Escherichia coli, and enterococci) intended to act as surrogates for human enteric pathogens. In environmental waters, this predictive relationship is confounded by many possible sources of FIB with varying implications for human health. Many physico-chemical and biological factors influence the fate of enteric pathogens and FIB in aquatic habitats, but are poorly understood, thus limiting our understanding of the usefulness of FIB as fecal pollution indicators.

These studies explored the field application of a “toolbox” approach to microbial source tracking (MST) intended to discriminate between human …