Digital Commons Network^™

Pervasive Iron Limitation At Subsurface Chlorophyll Maxima Of The California Current, Shane L. Hogle, Christopher L. Dupont, Brian M. Hopkinson, Andrew L. King, Kristen N. Buck, Kelly L. Roe, Rhona K. Stuart, Andrew E. Allen, Elizabeth L. Mann, Zackary I. Johnson, Katherine A. Barbeau

Marine Science Faculty Publications

Subsurface chlorophyll maximum layers (SCMLs) are nearly ubiquitous in stratified water columns and exist at horizontal scales ranging from the submesoscale to the extent of oligotrophic gyres. These layers of heightened chlorophyll and/or phytoplankton concentrations are generally thought to be a consequence of a balance between light energy from above and a limiting nutrient flux from below, typically nitrate (NO₃). Here we present multiple lines of evidence demonstrating that iron (Fe) limits or with light colimits phytoplankton communities in SCMLs along a primary productivity gradient from coastal to oligotrophic offshore waters in the southern California Current ecosystem. SCML …

Ocean Deoxygenation And Zooplankton: Very Small Oxygen Differences Matter, K. F. Wishner, Brad A. Seibel, C. Roman, C. Deutsch, D. Outram, Caroline T. Shaw, Matthew A. Birk, K. A. S. Mislan, T. J. Adams, D. Moore, S. Riley

Marine Science Faculty Publications

Oxygen minimum zones (OMZs), large midwater regions of very low oxygen, are expected to expand as a result of climate change. While oxygen is known to be important in structuring midwater ecosystems, a precise and mechanistic understanding of the effects of oxygen on zooplankton is lacking. Zooplankton are important components of midwater food webs and biogeochemical cycles. Here, we show that, in the eastern tropical North Pacific OMZ, previously undescribed submesoscale oxygen variability has a direct effect on the distribution of many major zooplankton groups. Despite extraordinary hypoxia tolerance, many zooplankton live near their physiological limits and respond to slight …

Mechanisms Of S1p-Induced Endothelial Barrier Enhancement, Natascha Guimarães Alves

USF Tampa Graduate Theses and Dissertations

Excessive microvascular permeability is a serious complication involved in traumatic injury and inflammatory diseases. Alcohol intoxication can exacerbate the physiological derangements produced by microvascular endothelial barrier dysfunction in such disease conditions. Sphingosine-1-phosphate (S1P) has known endothelial barrier-protective properties, and has been shown to ameliorate microvascular leakage in a model of combined alcohol intoxication and hemorrhagic shock and resuscitation (HSR). However, whether the barrier-protective properties of S1P extend to endothelial cells of the blood-brain barrier (BBB) is unclear. The mechanisms of S1P-induced barrier protection during alcohol intoxication or HSR are also unknown. In the current study, we tested the hypothesis that …

Relationships Between Microbial Indicators And Pathogens In Recreational Water Settings, Asja Korajkic, Brian R. Mcminn, Valerie J. Harwood

Integrative Biology Faculty and Staff Publications

Fecal pollution of recreational waters can cause scenic blight and pose a threat to public health, resulting in beach advisories and closures. Fecal indicator bacteria (total and fecal coliforms, Escherichia coli, and enterococci), and alternative indicators of fecal pollution (Clostridium perfringens and bacteriophages) are routinely used in the assessment of sanitary quality of recreational waters. However, fecal indicator bacteria (FIB), and alternative indicators are found in the gastrointestinal tract of humans, and many other animals and therefore are considered general indicators of fecal pollution. As such, there is room for improvement in terms of their use for informing risk assessment …

Sedimentary Age Models, Benthic Foraminifera, Mass Accumulation Rates, And Volcanic Grain Data From R/V Justo Sierra Cruise In The Southern Gulf And Ixtoc I From 2015-08-03 To 2015-08-06, Patrick Schwing

C-IMAGE data

This dataset includes age models, benthic foraminifera species counts used for stable isotope analysis, mass accumulation rates and volcanic grain counts from 6 sediment cores collected throughout the southern Gulf of Mexico during the R/V Justo Sierra cruise in the Southern Gulf and Ixtoc I from 2015-08-03 to 2015-08-06. Samples were analyzed by gamma spectrometry with High-Purity Germanium (HPGe) gamma-ray detectors (Canberra Coaxial Planar configuration) for total 210Pb (46.5 keV), 214Pb (295 keV and 351 keV), and 214Bi (609 keV) activities. The mean activity of the 214Pb (295 keV), 214Pb (351 keV), and 214Bi (609 keV) was used as a …

Cyclophilin 40 As A Novel Disaggregase, Jeremy Dustin Baker

USF Tampa Graduate Theses and Dissertations

The negative health and economic impacts of neurodegenerative diseases on Americans is astounding and accelerating with an aging population. The Alzheimer’s Association reports that 5.7 million Americans suffer from Alzheimer’s disease (AD), a number which is expected to increase to 14 million by 2050. In economic terms, AD and other neurodegenerative disorders will cost the US over $275 billion in 2018, rising to over $1 trillion annually by 2050. AD causes gross brain atrophy and is most damaging throughout the cortex and the hippocampus, regions required for higher cognitive function and memory. AD presents as tangles within neurons composed of …

Actinomycin D And Telmisartan Combination Therapy Targets Lung Cancer Stem Cells, Ryan Green

USF Tampa Graduate Theses and Dissertations

The failure of lung cancer treatments has been attributed partly to the development of drug resistance, however the underlying cellular and molecular mechanisms are poorly understood. It has been suggested that a very small group of specific cells within the heterogeneous tumors, cancer initiating stem cells (CSC), develop resistance to treatment, survive and later initiate the growth of new tumors. Due to their pivotal role in maintenance and relapse of tumors following the acquisition of drug resistance, we reasoned that novel drugs targeting cancer cells and CSC might provide the most effective treatments, if not a cure. To this end, …

Fatty Acid Amides And Their Biosynthetic Enzymes Found In Insect Model Systems, Ryan L. Anderson

USF Tampa Graduate Theses and Dissertations

A fatty acid amide is precisely as the name suggests: A fatty acid (CHn-COOH), in which the hydroxyl group of the carboxylic acid is displaced by an amine functional group from a biogenic amine (R-NH2), ultimately forming an amide bond. Furthermore, these fatty acid amides can be composed of a variety of different acyl chain lengths donated by the fatty acid and a myriad of different biogenic amines. Thus, these molecules can be subdivided in a number of different ways including the separation of short chain (acetyl to heptanoyl) and long chain (palmitoyl to arachidonoyl) and also based off the …

Human Body Motions Optimization For Able-Bodied Individuals And Prosthesis Users During Activities Of Daily Living Using A Personalized Robot-Human Model, Dimitrios Menychtas

USF Tampa Graduate Theses and Dissertations

Current clinical practice regarding upper body prosthesis prescription and training is lacking a standarized, quantitative method to evaluate the impact of the prosthetic device. The amputee care team typically uses prior experiences to provide prescription and training customized for each individual. As a result, it is quite challenging to determine the right type and fit of a prosthesis and provide appropriate training to properly utilize it early in the process. It is also very difficult to anticipate expected and undesired compensatory motions due to reduced degrees of freedom of a prosthesis user. In an effort to address this, a tool …

Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu

USF Tampa Graduate Theses and Dissertations

Urban Heat Island (UHI) is a growing problem worldwide. Mitigation of UHI is necessary for cities to adapt to climate change and enhance sustainable development at a city scale. Cooling cities with urban vegetation management is a sustainable solution for urban heat mitigation. Urban vegetation influences urban microclimate through the shading effect, surface roughness, and evapotranspiration. The differences in horizontal and vertical structures of urban vegetation determine the shading effect, surface roughness, and evapotranspiration. Enhancing the cooling effect of urban vegetation requires a comprehensive understanding of how vegetation structure affects UHI. The effects of horizontal structure on land surface temperature …

Behavioral Thermoregulation And Thermal Mismatches Influence Disease Dynamics In Amphibians, Erin Louise Sauer

USF Tampa Graduate Theses and Dissertations

Amphibians are currently the most threatened vertebra taxa on the planet. Hundreds of species are thought to have gone extinct while thousands more have been listed as threatened or endangered over the past few decades. Habitat loss, invasive species, climate change, and disease are all thought to have partially contributed to these declines. Two pathogens in particular, infectious viruses in the genus Ranavirus (simply referred to as ranavirus) and the fungus Batrachochytrium dendrobatidis (Bd), have been associated with global mass mortality events of amphibians. Virulent pathogens such as these tend to impose strong selective pressures on their hosts driving the …

Investigating The Roles Of Fucosylation And Calcium Signaling In Melanoma Invasion, Tyler S. Keeley

USF Tampa Graduate Theses and Dissertations

Melanoma is the deadliest form of skin cancer. Prognosis for early stage melanoma patients is excellent, and surgery is often curative for these patients. However, once patients have presented with invasive disease, the average 5-year survival rate drops significantly from over 90% to between 10 and 15%. Several therapies have been developed to target a commonly mutated oncogene BRAF, or its downstream effectors. Unfortunately, while these treatments show robust initial response, most patients relapse within a year. Moreover, therapy-resistant tumors are often more invasive and metastatic. Therefore, it is important to investigate the molecular mechanisms underlying melanoma invasion and metastasis, …

Investigation Of Anemarrhena Asphodeloides And Its Constituent Timosaponin-Aiii As Novel, Naturally Derived Adjunctive Therapeutics For The Treatment Of Advanced Pancreatic Cancer, Catherine B. Marelia

USF Tampa Graduate Theses and Dissertations

Pancreatic adenocarcinoma (PDAC) remains one of the most lethal cancer types, with 92% of patients succumbing to the disease within five years. One of the hallmarks of this intractable disease is its nearly universal resistance to chemotherapeutic intervention. The deoxycytidine analog gemcitabine persists as the primary chemotherapy for advanced PDAC patients despite little improvement to its toxicity and tenuous efficacy over the past two decades. Plant-based drug discovery has a longstanding history and has led to some of the most significant drugs of the modern era, including some chemotherapeutic agents like paclitaxel and camptothecin. Our study analyzed the potential inhibitory …

Investigating The Role Of The Rna Binding Protein Lin28 In The Human Placenta: Implications For Preeclampsia, John Canfield

USF Tampa Graduate Theses and Dissertations

An essential event during early pregnancy is the invasion of trophoblasts into the maternal decidua, which is necessary for proper implantation and establishment of maternal-fetal interface and ultimately allows for proper nutrient exchange and immunological tolerance of the growing fetus. For this invasion to occur, cells originating from the trophectoderm undergo an epithelial to mesenchymal transition to become invasive extravillous trophoblasts and begin invading the uterine decidual tissue. Through the secretion of matrix metalloproteinases and through interactions with many cytokines and cell-adhesion molecules, this well-orchestrated process of trophoblast invasion results in extensive remodeling of the maternal spiral vasculature by the …

Short-Lived Radioisotope Geochronology From Sediment Cores Collected During R/V Weatherbird Ii Cruises In The Northern Gulf Of Mexico From 2010-11-18 To 2016-09-09, Gregg R. Brooks, Rebekka A. Larson

C-IMAGE data

Short-lived Radioisotope (SLRad) data were generated for selected core sub-samples at 2mm sampling intervals for “surficial unit” and 5mm sampling resolution intervals to base of cores. SLRad data generated include sample activity as disintegrations per minute per gram (dpm/g) of: 1) Excess 234Th (234Thxs) activity, which is calculated by measuring the total 234Th (234ThTot) activity and the subtraction of the measured or estimated “Supported” 234Th (234ThSup) activity, 2) Excess 210Pb (210Pbxs) activity, which is calculated by measuring the total 210Pb (210PbTot) activity and subtraction of the measured background 210Pb (210PbSup) activity (average of 214Pb at 295keV, 214Pb at 351keV, and …

Sediment Texture And Composition Of Sediment Cores Collected During R/V Weatherbird Ii Cruises In The Northern Gulf Of Mexico From 2010-11-18 To 2016-09-09, Gregg R. Brooks, Rebekka A. Larson

C-IMAGE data

Sediment texture and composition data were generated for selected core sub-samples at 2mm sampling intervals for “surficial unit” and 5mm sampling resolution intervals to base of cores. Sediment texture values are expressed as % Gravel, % Sand, % Silt and % Clay as calculated by dry weight (g). % Mud can be calculated by combining % Silt and % Clay. Sediment composition is expressed as % carbonate content measured by acid leaching. This dataset supports the publication: Larson, R. A., Brooks, G. R., Schwing, P. T., Holmes, C. W., Carter, S. R., & Hollander, D. J. (2018). High-resolution investigation of …

Evaluating Human-Associated Escherichia Coli Marker Genes For Microbial Source Tracking Applications In Florida, Jacob K. Senkbeil

USF Tampa Graduate Theses and Dissertations

Fecal pollution of surface water can lead to human health issues because waterborne transmission of pathogens is a common cause of gastroenteritis. Genetic markers developed for human-associated Escherichia coli (H8, H12, H14, and H24) are promising tools for microbial source tracking (MST) of sewage in environmental waterbodies but are untested in the US. H gene marker performance characteristics (specificity, sensitivity, and prevalence) were assessed, with the goal of developing a quantitative PCR assay for the markers with the best performance. Individual E. coli isolates from reference samples were tested to determine end-point PCR assay performance. Three hundred E. coli strains …

Use Of A Towed Camera System Along The West Florida Shelf: A Case Study Of The Florida Middle Grounds Benthic Marine Communities, Katie S. Davis

USF Tampa Graduate Theses and Dissertations

As technologies advance the study of ocean dynamics, new approaches to vexing problems of scale and process are becoming more widely available. Originally conceived as a tool primarily for indexing the abundance of near-bottom fishes, the Camera-based Assessment and Survey System (C-BASS) may also be an effective tool for monitoring benthic invertebrate resources vulnerable to natural and anthropogenic perturbations, and for characterizing the composition of benthic communities to inform spatial management. Using still images derived from the C-BASS video of benthic transects within the Florida Middle Grounds, I documented the abundance of benthic habitat-forming functional groups—sponges, algae, and corals—and noted …

Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich

USF Tampa Graduate Theses and Dissertations

Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the …

Estimating The Elimination Feasibility In The 'End Game' Of Control Efforts For Parasites Subjected To Regular Mass Drug Administration: Methods And Their Application To Schistosomiasis, Arathi Arakala, Christopher M. Hoover, John M. Marshall, Susanne H. Sokolow, Guilio A. De Leo, Jason R. Rohr, Justin V. Remais, Manoj Gambhir

Integrative Biology Faculty and Staff Publications

Progress towards controlling and eliminating parasitic worms, including schistosomiasis, onchocerciasis, and lymphatic filariasis, is advancing rapidly as national governments, multinational NGOs, and pharmaceutical companies launch collaborative chemotherapeutic control campaigns. Critical questions remain regarding the potential for achieving elimination of these infections, and analytical methods can help to quickly estimate progress towards—and the probability of achieving—elimination over specific timeframes. Here, we propose the effective reproduction number, R_eff, as a proxy of elimination potential for sexually reproducing worms that are subject to poor mating success at very low abundance (positive density dependence, or Allee effects). R_eff is the …

Hurricane-Induced Changes In The Everglades National Park Mangrove Forest: Landsat Observations Between 1985 And 2017, Xingxing Han, Lian Feng, Chuanmin Hu, Philip Kramer

Marine Science Faculty Publications

The Everglades National Park (ENP) has one of the largest mangrove forests in the United States, yet due to lack of data and methods, there has been no multidecadal record of detailed changes in its mangrove forests, not to mention their response to periodic hurricanes. Here, based on remote sensing spectroscopy, multisensor cross calibration, spectral normalization, and pixel unmixing, we develop a stepwise method to map distributions and changes of the ENP mangrove forests and other major wetlands cover types (marshes and hardwood hammocks) over the last three decades. The time series of Landsat-based results indicate statistically significant increasing trend …

Fluctuating Fishing Intensities And Climate Dynamics Reorganize The Gulf Of Mexico's Fisheries Resources, Joshua P. Kilborn, Michael Drexler, David L. Jones

Marine Science Faculty Publications

Integrated ecosystem assessment provides a practical framework for implementing ecosystem‐based fisheries management (EBFM) while also balancing socioeconomic and ecological objectives. However, significant challenges remain, including (1) the identification of relevant ecosystem‐level fisheries management indicators; (2) quantitatively describing the historical qualitative changes to fisheries ecosystem resource organization; (3) elucidating dynamic system regimes and their trade‐offs related to variability in both natural and anthropogenic drivers; and (4) distilling and communicating the results to stakeholders and managers. Here, we describe the Ecosystem‐Level, Management‐Indicator Selection Tool (EL‐MIST), which was developed to address these EBFM challenges. We also present a case study from the Gulf …

Coastal Ocean And Continental Shelves, Chuanmin Hu, Frank Muller-Karger, Lisa Robbins

Marine Science Faculty Publications

No abstract provided.

Remote Sensing Of Sargassum Biomass, Nutrients, And Pigments, Mengqiu Wang, Chuanmin Hu, Jennifer Cannizzaro, David English, Xingxing Han, David Naar, Brian Lapointe, Rachel Brewton, Frank Hernandez

Marine Science Faculty Publications

Field and laboratory experiments are designed to measure Sargassum biomass per area (density), surface reflectance, nutrient contents, and pigment concentrations. An alternative floating algae index-biomass density model is established to link the spectral reflectance to Sargassum biomass density, with a relative uncertainty of ~12%. Monthly mean integrated Sargassum biomass in the Caribbean Sea and central West Atlantic reached at least 4.4 million tons in July 2015. The average %C, %N, and %P per dry weight are 27.16, 1.06, and 0.10, respectively. The mean chlorophyll-a (Chl-a) concentration is ~0.05% of the dry weight. With these parameters, the amounts of nutrients and …

A 3,000‐Year Lag Between The Geological And Ecological Shutdown Of Florida's Coral Reefs, Lauren T. Toth, Isla B. Kuffner, Anastasios Stathakopoulos, Eugene Shinn

Marine Science Faculty Publications

The global‐scale degradation of coral reefs has reached a critical threshold wherein further declines threaten both ecological functionality and the persistence of reef structure. Geological records can provide valuable insights into the long‐term controls on reef development that may be key to solving the modern coral‐reef crisis. Our analyses of new and existing coral‐reef cores from throughout the Florida Keys reef tract (FKRT) revealed significant spatial and temporal variability in reef development during the Holocene. Whereas maximum Holocene reef thickness in the Dry Tortugas was comparable to elsewhere in the western Atlantic, most of Florida's reefs had relatively thin accumulations …

Integrated Observations And Informatics Improve Understanding Of Changing Marine Ecosystems, Abigail Benson, Cassandra M. Brooks, Gabrielle Canonico, Emmett Duffy, Frank Muller-Karger, Heidi M. Sosik, Patricia Miloslavich, Eduardo Klein

Marine Science Faculty Publications

Marine ecosystems have numerous benefits for human societies around the world and many policy initiatives now seek to maintain the health of these ecosystems. To enable wise decisions, up to date and accurate information on marine species and the state of the environment they live in is required. Moreover, this information needs to be openly accessible to build indicators and conduct timely assessments that decision makers can use. The questions and problems being addressed demand global-scale investigations, transdisciplinary science, and mechanisms to integrate and distribute data that otherwise would appear to be disparate. Essential Ocean Variables (EOVs) and marine Essential …

Bp Gulf Science Data Reveals Ineffectual Subsea Dispersant Injection For The Macondo Blowout, Claire B. Paris-Limouzy, Igal Berenshtein, Marica L. Trillo, Robin Faillettaz, Maria J. Olascoaga, Zachary M. Aman, Michael Schlüter, Samantha B. Joye

C-IMAGE Publications

After the Deepwater Horizon oil platform explosion, an estimated 172.2 million gallons of gas-saturated oil was discharged uncontrollably into the Gulf of Mexico, causing the largest deep-sea blowout in history. In an attempt to keep the oil submerged, massive quantities of the chemical dispersant Corexit^® 9500 were deployed 1522 m deep at the gushing riser pipe of the Macondo prospect’s wellhead. Understanding the effectiveness of this unprecedented subsea dispersant injection (SSDI) is critical because deep-water drilling is increasing worldwide. Here we use the comprehensive BP Gulf Science Data (GSD) to quantify petroleum dynamics throughout the 87-day long blowout. The …

An Examination Of The Relationship Between Health Literacy And Dietary Practices Among College Students: A Test Of The Integrated Model Of Health Literacy, Alison B. Oberne

USF Tampa Graduate Theses and Dissertations

Overweight and obesity continue to plague Americans and contribute to decreased quantity and quality of life. Americans of all ages experience overweight and obesity; however, increasing rates occur during young adulthood. Young adults develop dietary practice behaviors that persist into adulthood and can contribute to weight-related chronic diseases. Approximately half of all young adults are enrolled in college, and, approximately 38% of college students are either overweight or obese.

Dietary practices are health behaviors that can either increase or decrease risk for overweight and obesity. Much research has explored predictors of dietary practices among college students; however, there is a …

Neutrophil Extracellular Traps And Vascular Barrier Injury, Jamie E. Meegan

USF Tampa Graduate Theses and Dissertations

Sepsis is a life-threatening inflammatory condition with high morbidity and mortality rates. Though improvements to diagnosis and management of sepsis have been made, the complexity of the disease process and an incomplete understanding of its endpoint mechanisms have prevented major breakthroughs for early diagnosis and treatment. Representing a common endpoint in a number of inflammatory injuries including sepsis, endothelial barrier dysfunction causes fluid leakage and leukocyte infiltration that leads to tissue damage and multiple organ failure. Therefore, elucidating mechanisms of endothelial barrier regulation is needed to further develop targeted therapies in inflammatory disease.

Sepsis is characterized by a hyperinflammatory response …

An Investigation Of Habitat Suitability Factors And Their Interactions For Predicting Gopher Tortoise Habitat, Abigail V. Lavallin

USF Tampa Graduate Theses and Dissertations

This thesis evaluates the interaction between four habitat factors vital to the gopher tortoise in Florida. Federally and state listed as threatened throughout its entire range, the gopher tortoise is vital to protect, not only for itself individually but its burrows provide an essential habitat to over 300 species making it a key stone species within its environment. Historic habitat modeling methods are reviewed for the gopher tortoise to highlight the gap on this topic. This research expanded on the methods utilized by Baskaran et al. (2006) evaluating the soil, landcover, percentage of canopy cover and the depth to water …