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USF Tampa Graduate Theses and Dissertations

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Cue Reactivity And The Role Of Social Alcohol Expectancies In The College-Aged Drinking Population, Ashlee C. Carter Jan 2006

Cue Reactivity And The Role Of Social Alcohol Expectancies In The College-Aged Drinking Population, Ashlee C. Carter

USF Tampa Graduate Theses and Dissertations

Research has shown alcohol expectancies to be critically important in understanding maladaptive drinking patterns within alcohol use disorders. Alcohol expectancies, thought to be automatically elicited in the presence of environmental alcohol-related cues, represent both cognitive and affective associations with drinking behavior. However, the automatic and affective properties of alcohol expectancies have not yet been thoroughly measured in the literature. Psychophysiological measures, including skin conductance, heart rate, and the acoustic startle response in particular, offer a uniquely powerful set of indices for the automatic affective processing of alcohol-related cues.

Therefore, the present study was designed to examine how alcohol expectancies moderate …


Enzyme Linked Spectroscopic Assays For Glyoxylate; The Use Of Peptidylglycine Alpha-Amidating Monoxygenase For The Discovery Of Novel Alpha-Amidated Hormones, Sarah Elizabeth Carpenter Jan 2006

Enzyme Linked Spectroscopic Assays For Glyoxylate; The Use Of Peptidylglycine Alpha-Amidating Monoxygenase For The Discovery Of Novel Alpha-Amidated Hormones, Sarah Elizabeth Carpenter

USF Tampa Graduate Theses and Dissertations

Peptide hormones are responsible for cellular functions critical to the survival of an organism. Approximately 50% of all known peptide hormones are post-translationally modified at the C-terminus. Enzymatic oxidative conversion of C-terminal glycine extended peptide precursors results in an a-amidated peptide and glyoxylate. Peptidylglycine a-amidating monooxygenase (PAM) is the single known enzyme responsible for catalyzing this reaction. PAM is an O2, Cu(II), and Zn(II) dependent bifunctional enzyme. Initially, PAM hydroxylates the glycyl a-carbon followed by dealkylation of the hydroxylated intermediate to an a-amidated product and glyoxylate. PAM is also responsible for the conversion of glycine extended fatty acids to fatty …


Monitoring Water Quality In Tampa Bay: Coupling In Situ And Remote Sensing, Zhiqiang Chen Jan 2006

Monitoring Water Quality In Tampa Bay: Coupling In Situ And Remote Sensing, Zhiqiang Chen

USF Tampa Graduate Theses and Dissertations

Water quality in Tampa Bay was examined using concurrent in situ and satellite remote sensing observations. Chlorophyll and suspended sediment concentrations showed large short-term variability, primarily driven by tide and wind forcing. Superimposed on these high frequency variations were recurrent phytoplankton blooms stimulated by decreases in turbidity 1-2 days after wind-induced bottom sediment resuspension events; the blooms were particularly strong if neap tides occurred after the wind events. The in situ data show that observations once per month are inadequate to sample short-term variability and that therefore the current monthly water quality surveys may have uncertainties of -50 to 200% …


Genetic Variation In The Chloroplast Genome Of A Newly Described Aster Species, Chrysopsis Delaneyi, Justine Ann Clark Jan 2006

Genetic Variation In The Chloroplast Genome Of A Newly Described Aster Species, Chrysopsis Delaneyi, Justine Ann Clark

USF Tampa Graduate Theses and Dissertations

The genus Chrysopsis (Asteraceae) contains eleven species native to Florida, including the newly described species, Chrysopsis delaneyi. Populations of this endemic plant species inhabit the Lake Wales Ridge (LWR) and the Atlantic Ridge (AR) of the Florida peninsula. Differences in morphology have been demonstrated within C. delaneyi, based on their locations. My objective was to determine the relationships between the LWR and the AR populations by analysis of chloroplast sequence and nuclear sequence variation. Approximately 160 samples of C. delaneyi and its sister species C. scabrella have been collected from fifteen sites throughout Florida. Six single base differences were detected, …


Traumatic Loss And Transformative Life Experiences: The Lived Experience Of Green Cross Traumatologists Deployed To The New York City World Trade Center Disaster, Carron C. Cherrie Jan 2006

Traumatic Loss And Transformative Life Experiences: The Lived Experience Of Green Cross Traumatologists Deployed To The New York City World Trade Center Disaster, Carron C. Cherrie

USF Tampa Graduate Theses and Dissertations

This exploratory study examines the lived experience of Green Cross traumatologists deployed to the New York City World Trade Center disaster. The deployment took place five days after the terrorist attacks on September 11, 2001. The author was a member of a ten member advance team that provided crisis stabilization services to an international union in Lower Manhattan. Disaster Mental Health Services and community outreach were provided for a month. The purpose of the study was to describe in an anthropologically holistic perspective the lived experience of traumatologists, who as Americans were also affected by the terrorist disaster. Thirty-one traumatologists …


Herbivory By Leaf Miners On Florida Scrub Oaks, Tatiana Cornelissen Jan 2006

Herbivory By Leaf Miners On Florida Scrub Oaks, Tatiana Cornelissen

USF Tampa Graduate Theses and Dissertations

This study investigated effects of plant quality and natural enemies on the abundance and survivorship of several leaf miner species on Florida scrub oaks over several ecological scales. Three oak species (Quercus laevis, Q. geminata, and Q. myrtifolia) and four leafminer species (Acrocercops albinatella, Brachys tesselatus, Stilbosis quadripustulatus, and Cameraria sp. nova) were the main focus of five separate studies, addressing effects of bottom-up and top-down factors at regional, local, and individual scales. At the regional scale, it was observed that Cameraria sp. nova was aggregated into sites, and sites closer to …


Parent Involvement: Differences Between African Americans And European Americans In One Florida School District, Michelle Darter-Lagos Jan 2006

Parent Involvement: Differences Between African Americans And European Americans In One Florida School District, Michelle Darter-Lagos

USF Tampa Graduate Theses and Dissertations

The purpose of this research study was to (a) analyze perceptions of parent involvement across raters (i.e., seventh grade students versus their parents) and across ethnicity (i.e., African American versus European American), and (b) examine how perceptions of parent involvement are related to academic achievement. A subsample of archival survey data collected in one central Florida school district was analyzed for the current study. Findings revealed a positive but weak relationship between students' and parents' perceptions of parent involvement regardless of ethnicity. Significant differences were found in the perceived levels of involvement by ethnicity, even when controlling for SES. In …


Risk And Protective Factors Related To Resilience In Adolescents In An Alternative Education Program, Kelly M. Crawford Jan 2006

Risk And Protective Factors Related To Resilience In Adolescents In An Alternative Education Program, Kelly M. Crawford

USF Tampa Graduate Theses and Dissertations

Using a multivariate correlational design, this study was designed to determine the degree to which selected risk and protective factors were related to resilience in an at-risk student population. A total of 12 individual, family and external risk and protective factors were identified and data were collected from 142 6th through 11th grade students in an alternative education program for individuals who had committed severe behavioral infractions. A series of multiple regression analyses were conducted using three outcome variables: a rating of students' resilient behavior, number of behavior referrals in the students' records, and standardized reading achievement scores. Five percent …


Reconstructing 20th Century Sst Variability In The Southwest Pacific: A Replication Study Using Multiple Coral Sr/Ca Records From New Caledonia, Kristine L. Delong Jan 2006

Reconstructing 20th Century Sst Variability In The Southwest Pacific: A Replication Study Using Multiple Coral Sr/Ca Records From New Caledonia, Kristine L. Delong

USF Tampa Graduate Theses and Dissertations

Coral-based climate reconstructions typically have not used multiple cores from a region to capture and replicate a climate signal largely because of concerns focused on coral conservation, analytical expense, and time constraints. Coral Sr/Ca reproducibility through the 20th century was investigated using three intra-colony and three inter-colony coral records, from the reefs offshore of Amédée Island, New Caledonia. Different sampling resolutions were examined in coral Sr/Ca (fortnightly and monthly) and delta 18O (fortnightly, monthly, and seasonally) as well as similar scale subsampling of the daily in situ SST record. The mean coral Sr/Ca, delta 18O, and daily SST values do …


Pain As A Motivator Of Smoking: Effects Of Pain Induction On Smoking Urge And Behavior, Joseph W. Ditre Jan 2006

Pain As A Motivator Of Smoking: Effects Of Pain Induction On Smoking Urge And Behavior, Joseph W. Ditre

USF Tampa Graduate Theses and Dissertations

Tobacco smoking has been associated with the development, protraction, and exacerbation of chronically painful conditions. Conversely, there is reason to believe that smokers may be motivated to use tobacco as a means of coping with their pain. To date, no controlled, experimental studies have tested for a causal relationship between pain and smoking motivation. The primary aim of the current study was to test the hypothesis that laboratory-induced cold-pressor pain would enhance smoking motivation, as measured by self-reported urge to smoke and observation of immediate smoking behavior. The effect of a smoking cue was also tested. Smokers (n = 132) …


The Identification Of Functional, Sequestered, Symbiotic Chloroplasts In Elysia Clarki: A Crucial Step In The Study Of Horizontally Transferred, Nuclear Algal Genes, Nicholas E. Curtis Jan 2006

The Identification Of Functional, Sequestered, Symbiotic Chloroplasts In Elysia Clarki: A Crucial Step In The Study Of Horizontally Transferred, Nuclear Algal Genes, Nicholas E. Curtis

USF Tampa Graduate Theses and Dissertations

A comparison of Elysia (=Tridachia) crispata (Mörch, 1863) from the Virgin Islands with elysiid slugs from the mangrove swamps and canals in the Florida Keys that have previously been identified as E. crispata reveals many differences in habitat, gross and microscopic anatomy, food preferences of juveniles, sources of symbiotic chloroplasts and their localization within the digestive tubules, radular morphology, and nucleic acid sequences of two genes. The differences between the two groups of slugs are such that the Florida Keys animals are considered to represent a new species, Elysia clarki. Elysia clarki feeds on siphonaceous algae, and intracellularly sequesters the …


Rapid Detection Of Mycobacterium Tuberculosis In Lung Tissue Using A Fiber Optic Biosensor, Kimberly A. Denton Jan 2006

Rapid Detection Of Mycobacterium Tuberculosis In Lung Tissue Using A Fiber Optic Biosensor, Kimberly A. Denton

USF Tampa Graduate Theses and Dissertations

There is no rapid diagnostic technique at medical examiners' offices to determine if a decedent is infected with Mycobacterium tuberculosis. Present diagnostic testing requires at least one month for results. A biosensor-based sandwich immunoassay for the detection of M. tuberculosis was developed in this study. M. tuberculosis polyclonal antibody was used for target antigen capture and detection in the immunoassay. Live attenuated M. tuberculosis (ATCC 25177) suspended in phosphate-buffered saline with 0.1% Tween 20 was used as the antigen in the detection assay. The Analyte 2000 was the initial biosensor platform. Initial testing was of Freund's adjuvant complete. M. tuberculosis …


The Role Of Src Homology 2 Domain Containing Inositol-5’-Phosphatase 1 (Ship) In Hematopoietic Cells, Caroline Desponts Jan 2006

The Role Of Src Homology 2 Domain Containing Inositol-5’-Phosphatase 1 (Ship) In Hematopoietic Cells, Caroline Desponts

USF Tampa Graduate Theses and Dissertations

The principal isoform of Src homology (SH) 2-domain containing 5' inositol phosphatase protein 1 (SHIP) is a 145kDa protein primarily expressed by cells of the hematopoietic compartment. The enzymatic activity of SHIP is responsible for hydrolyzing the 5' phosphate of phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3), and thereby preventing the recruitment of pleckstrin homology domain containing effector proteins. Furthermore, SHIP contains protein-protein interaction domains, such as an SH2 domain, two NPXY and several proline-rich motifs. All of these different domains endow SHIP with the capacity to impact signaling pathways important for proliferation, survival, differentiation and activation. Therefore, we hypothesized that SHIP-deficiency could result in …


Optical Imaging Of Radiolabeled Drugs In Tissue Sections Using The Microimager, Paul Dungel Jan 2006

Optical Imaging Of Radiolabeled Drugs In Tissue Sections Using The Microimager, Paul Dungel

USF Tampa Graduate Theses and Dissertations

The MicroImager is a fast, high resolution, real time, digital autoradiographic imaging tool with broad applications. This study utilizes the MicroImager to evaluate radiolabeled drug behavior in subcutaneous tissue. Experiments were conducted in conjunction with mathematical models to determine the diffusion coefficient (D) and elimination constant (k) for radiolabeled dexamethasone. Osmotic pumps containing [3H]dexamethasone were implanted into rat subcutaneous tissue over 6h, 24 h, and 60 h. Local tissue was explanted and slides were prepared for imaging. The MicroImager was then used to quantify the local concentration of 3H-dexamethasone in the tissue surrounding the tip of the osmotic pump. Betavision+ …


Vibration Level Characterization From A Needle Gun Used On U.S. Naval Vessels, Scott E. Dunn Jan 2006

Vibration Level Characterization From A Needle Gun Used On U.S. Naval Vessels, Scott E. Dunn

USF Tampa Graduate Theses and Dissertations

United States (U.S.) Navy sailors are exposed to a very large number of hazards, both chemical and physical. Occupational vibration from pneumatic air tools is one of the potential exposure hazards. There are very limited data as to the exposures to one type of tool, a needle gun or needle scaler, used by the sailors.The purpose of this study was to characterize the vibration levels generated by a needle gun used in the U.S. Navy. The design of the study evaluated the difference pressure had on the acceleration levels generated from the needle scaler. Five subjects were used in the …


Monitoring And Modeling Water Quality At The C.W. Young Regional Reservoir, Daniel Robert Dye Jan 2006

Monitoring And Modeling Water Quality At The C.W. Young Regional Reservoir, Daniel Robert Dye

USF Tampa Graduate Theses and Dissertations

This work explores the relationship between nutrient loading and changes in water quality in a sub-tropical, above-ground, off-stream municipal water supply reservoir, the C.W. Bill Young Regional Reservoir. The three source waters for the reservoir have varied but high levels of nutrients such as phosphorus and nitrogen. In other reservoirs, these nutrients have been linked to deterioration of water quality and increased expense in water treatment. The need to minimize excess nutrients results led to the primary research question: what allocation of withdrawals from the three sources will minimize the deterioration of water quality? To answer this question, the relationship …


Alcohol Expectancy Cognitions: Psychophysiological Perspective, Inna Fishman Jan 2006

Alcohol Expectancy Cognitions: Psychophysiological Perspective, Inna Fishman

USF Tampa Graduate Theses and Dissertations

Considerable evidence indicates that the expectations individuals hold about the effects of alcohol determine, to a degree, the amount of alcohol they drink. However, the bulk of this evidence was acquired using verbally-based measures of expectancy. The present study sought to extend the validation network by utilizing an electrophysiological measure -- the P300 component of the Event Related Potentials (ERPs) --

which is thought to index fundamental neurophysiological processes sensitive to expectancy.Previous research has demonstrated that, when presented with various outcomes of alcohol consumption, heavier drinkers endorse statements that assert positive and arousing effects of alcohol, while lighter drinkers endorse …


Nurse Exposure To Waste Anesthetic Gases In A Post Anesthesia Care Unit, Larry A. Flack Jan 2006

Nurse Exposure To Waste Anesthetic Gases In A Post Anesthesia Care Unit, Larry A. Flack

USF Tampa Graduate Theses and Dissertations

It has been estimated that over 200,000 healthcare professionals may be exposed to waste anesthetic gases and are at risk of occupational injury. In 1977, the National Institute for Occupational Safety and Health (NIOSH) issued the publication: Criteria for a Recommended Standard....Occupational Exposure to Waste Anesthetic Gases and Vapors. This publication was based primarily on scientific evidence from human and animal studies suggesting that chronic exposures to anesthetic gases increases the risk of both spontaneous abortion and congenital abnormalities in offspring among female workers and wives of male workers exposed to waste anesthetic gases. In this recommended standard, NIOSH defines …


Functional Topology And Regulation Of Endothelial Nitric Oxide Synthase And Associated Caveolar Components, Brenda R. Flam Jan 2006

Functional Topology And Regulation Of Endothelial Nitric Oxide Synthase And Associated Caveolar Components, Brenda R. Flam

USF Tampa Graduate Theses and Dissertations

The discovery of nitric oxide (NO) as the endothelial-derived relaxing factor has led to significant research on NO and the proteins involved in its function, generation, location and regulation. Synthesis of NO by blood vessel endothelial cells results from the enzymatic oxidation of arginine by endothelial nitric oxide synthase (eNOS) resulting in the formation of equimolar amounts of NO and citrulline. Citrulline is sequentially recycled to arginine by successive reactions involving the enzymes argininosuccinate synthase (AS) and argininosuccinate lyase (AL), respectively.

eNOS activity has been shown to be regulated by post-translational modifications including dynamic phosphorylation on multiple serine/threonine and tyrosine …


Comparison Of The Effects Of Training In Expository Text Structure Through Annotation Textmarking And Training In Vocabulary Development On Reading Comprehension Of Students Going Into Fourth Grade, Lily Janise Gentry Jan 2006

Comparison Of The Effects Of Training In Expository Text Structure Through Annotation Textmarking And Training In Vocabulary Development On Reading Comprehension Of Students Going Into Fourth Grade, Lily Janise Gentry

USF Tampa Graduate Theses and Dissertations

Fifty-seven pre-fourth-graders from 14 private schools participated to determine (a) if teaching text structure with annotation produced higher comprehension scores than the method of teaching vocabulary, and (b) if the effect of instructional method on reading comprehension was the same for male and female students. Effects were measured by immediate posttest and follow-up test NCE scores of the Stanford Diagnostic Reading Test, Fourth Edition (SDRT4) containing components of Comprehension and Vocabulary. The design was a true experiment using a matched comparison-group format. Participants were placed in one of two independent 3-week reading workshop sessions, then randomly assigned to one of …


Powerful Submission: Popular Texts And The Subjectivity Of Christian Right Women, Ellen L. Flournoy Jan 2006

Powerful Submission: Popular Texts And The Subjectivity Of Christian Right Women, Ellen L. Flournoy

USF Tampa Graduate Theses and Dissertations

The Christian Right exerts considerable influence over female identity, especially through its members who have emerged as one of the most powerful voting blocks in the nation---the Christian Right woman. American Christian women, especially those considered to be on the political fringes, are virtually ignored in academic endeavors. Given their power, which defies their categorization as a "fringe" group, this academic silence is a gross oversight, especially in light of the rise of the Christian Right, which has successfully recruited millions of women to its service. This dissertation analyzes texts of Christian popular culture that contribute to the construction of …


Development Of A Microsphere-Based Immunoassay For The Detection Of Igm Antibodies To West Nile Virus And St. Louis Encephalitis Virus In Sentinel Chicken Sera, Logan C. Haller Jan 2006

Development Of A Microsphere-Based Immunoassay For The Detection Of Igm Antibodies To West Nile Virus And St. Louis Encephalitis Virus In Sentinel Chicken Sera, Logan C. Haller

USF Tampa Graduate Theses and Dissertations

West Nile virus (WNV) and St. Louis Encephalitis (SLEV) are arthropod-borne viruses belonging to the genus Flavivirus and are classified as significant human pathogens of global epidemiological importance. Since its introduction into the United States in 1999, WNV has spread throughout most of the country and has caused major epidemics of neuroinvasive disease (Hayes and Gubler, 2005). SLEV is endemic to the United States and is maintained in an enzootic transmission cycle in Florida.The Florida Sentinel Chicken Arboviral Surveillance Network was established in 1978 following a widespread rural epidemic of SLEV in central Florida to monitor the activity of arboviruses …


Modulation Of Neural Plasticity By The Adamtss (A Disintegrin And Metalloproteinase With Thrombospondin Motifs), Michelle Grace Hamel Jan 2006

Modulation Of Neural Plasticity By The Adamtss (A Disintegrin And Metalloproteinase With Thrombospondin Motifs), Michelle Grace Hamel

USF Tampa Graduate Theses and Dissertations

Aggregating proteoglycans (PG) bearing chondroitin sulfate (CS) side chains are well-known inhibitors of neural plasticity and associate with hyaluronan and tenascin-R to form a complex of extracellular matrix (ECM) in the central nervous system (CNS). Little is known about whether proteolytic cleavage of the core protein affects neural plasticity. Several members of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of metalloproteinases are glutamyl-endopeptidases that cleave aggregating PGs. Our initial studies determined that neural cultures secrete a brevican-containing matrix, and that these neural cultures also produced ADAMTS4, a protease that cleaves brevican. Furthermore, this brevican-containing matrix in astrocytes …


Chemical Investigation Of Two Antarctic Invertebrates, Synoicum Adareanum (Chordata: Ascidiaceae: Enterogona:Polyclinidae) And AustrodorisKergulenensis (Molusca: Gastropoda:Nudibranchia: Dorididae), Thushara Kelum Kaviraj Diyabalanage Jan 2006

Chemical Investigation Of Two Antarctic Invertebrates, Synoicum Adareanum (Chordata: Ascidiaceae: Enterogona:Polyclinidae) And AustrodorisKergulenensis (Molusca: Gastropoda:Nudibranchia: Dorididae), Thushara Kelum Kaviraj Diyabalanage

USF Tampa Graduate Theses and Dissertations

Synoicum adareanum is a colonial tunicate commonly found on the benthos around Palmer Station on Anvers Island, Antarctica. A comprehensive chemical investigation of the lipophilic extract of the frozen tunicates gave a new series of polyketide macrolides, palmerolides A-E and H. The structure elucidation of these compounds was accomplished by extensive NMR and mass spectral studies.The palmerolides are unusual 20-membered macrolides displaying functionality more commonly found in sponges or cyanobacteria. Palmerolide A, the major member of the group, shows significant and selective in vitro cytotoxicity against melanoma with three orders of greater sensitivity relative to other cell lines tested, in …


Confronting College: Foster Care Youth Deciding Whether To Participate In Higher Education Programs, Linda K. Herlocker Jan 2006

Confronting College: Foster Care Youth Deciding Whether To Participate In Higher Education Programs, Linda K. Herlocker

USF Tampa Graduate Theses and Dissertations

This study's purpose was to explore the college choice process for foster care youth who are aging out of Florida's protective services system. The research methodology included three components. First, a survey of the Independent Living Coordinators throughout the state of Florida solicited data regarding participation rates and enrollment patterns among foster care youth. Next, in a meeting setting, a survey was administered to foster care youth, probing the extent to which they considered certain college choice decision factors. Finally, upon completion of the survey, participants remained for a guided focus group discussion to further explore their decision criteria.The results …


The Early Time Course Of Smoking Withdrawal Symptoms, Peter Schuyler Hendricks Jan 2006

The Early Time Course Of Smoking Withdrawal Symptoms, Peter Schuyler Hendricks

USF Tampa Graduate Theses and Dissertations

Despite the large volume of research on tobacco withdrawal, the vast majority of studies have focused on the onset and remission of symptoms over the course of several days and weeks, with the earliest assessment periods occurring the day after cessation. To date, there has been no systematic study of the very early time course of the tobacco withdrawal syndrome, despite its obvious relevance to the maintenance of both smoking and postcessation abstinence. The published literature contains a range of estimates about the early appearance of withdrawal symptoms, but without reference to empirical data. The main objective of the current …


Improving Prostate Cancer Detection In Veterans Through The Development Of A Clinical Decision Rule For Prostate Biopsy, Owen T. Hill Jan 2006

Improving Prostate Cancer Detection In Veterans Through The Development Of A Clinical Decision Rule For Prostate Biopsy, Owen T. Hill

USF Tampa Graduate Theses and Dissertations

In the U.S., the number of prostate biopsies increases annually. This is partly due to elevated prostate specific antigen (PSA) values identified during PC screening. This study's goal was improving prostate cancer (PC) detection through developing a clinical decision rule (CDR), based on an elevated PSA and laboratory biomarkers. This decision rule could be used after an elevated PSA, providing the patient and clinician information to consider prior to biopsy. This cross-sectional study evaluated men from the Tampa, Florida, James A. Haley (JH) VA (N=1,378), from January 1, 1998, through April 15, 2005. The study hypothesized that specific lab biomarkers …


Abrupt Climate Change During The Last Glacial Period: A Gulf Of Mexico Perspective, Heather W. Hill Jan 2006

Abrupt Climate Change During The Last Glacial Period: A Gulf Of Mexico Perspective, Heather W. Hill

USF Tampa Graduate Theses and Dissertations

Understanding the cause of abrupt climate change in the geologic past can help assess the potential magnitude and variability of future changes in regional and global climate. The research presented here focuses on some of the first records of hydrologic variability in the central North American continent during an interval of Marine Isotope Stage 3 (24-57 thousand years before present (ka)). Sediment core MD02-2551 from the Orca Basin, northern Gulf of Mexico, is used to document the first detailed melting history of the southern margin of the Laurentide Ice Sheet (LIS) during MIS 3, and to record terrestrial inputs from …


Gold Mining In A Tropical Rainforest: Mercury Sorption To Soils In The Mining Region Of Arakaka-Matthew's Ridge, Guyana, Joniqua A'Ja Howard Jan 2006

Gold Mining In A Tropical Rainforest: Mercury Sorption To Soils In The Mining Region Of Arakaka-Matthew's Ridge, Guyana, Joniqua A'Ja Howard

USF Tampa Graduate Theses and Dissertations

Gold mining by artisinal (small-medium scale) miners causes an immense amount of damage to the environment (i.e. soil erosion, mobilization of heavy metals, etc.).1, 2 One of the most popular gold mining techniques employed by artisinal miners in Guyana is mercury amalgamation. During the amalgamation process approximately 300 metric tons/yr 11, 12 of mercury is used. Mercury once in the environment can be transported through the air, soil, and water column. It is estimated that 90-99% of total mercury (THg) is associated with the sediment. An understanding of the geochemical conditions that affect the fate of mercury in soils, which …


Cranial Biomechanics And Feeding Performance Of Sharks, Daniel Robert Huber Jan 2006

Cranial Biomechanics And Feeding Performance Of Sharks, Daniel Robert Huber

USF Tampa Graduate Theses and Dissertations

The elasmobranch fishes possess a remarkable diversity of feeding mechanisms for a group containing relatively few species (~1200). The three most prevalent of these mechanisms involve prey capture during which the predator overtakes its prey (ram), prey is drawn into the mouth of the predator (suction), and relatively stationary consumption of sessile or substrate affixed prey (biting). Biomechanical modeling of cranial force distributions, in situ bite performance trials, and kinematic analysis of prey capture behaviors were employed to identify morphological and behavioral specializations and constraints associated with these feeding mechanisms in lemon Negaprion brevirostris (ram), whitespotted bamboo Chiloscyllium plagiosum (suction), …