Life Sciences Commons^™

Monitoring Photosynthetic Activity Using In Vivo Chlorophyll A Fluorescence In Microalgae And Cyanobacteria Biofilms In The Nerja Cave (Malaga, Spain), Yolanda Del Rosal, Juan Muñoz-Fernández, Paula S.M. Celis-Plá, Mariona Hernández-Mariné, Félix Álvarez-Gómez, Salvador Merino, Félix L. Figueroa

International Journal of Speleology

The characterization of the most common photosynthetic biofilms in the Nerja Cave by the continuous monitoring of the in vivo chlorophyll a (Chl a) fluorescence and the incorporation of the irradiance as a new environmental variable related to previous studies in the cave, have allowed us to improve our knowledge about the photosynthetic pattern of the biofilms of the cave. Effective quantum yield (ΔF/F_m′) and relative electron transport rate (rETR) were determined during periods of the light, whereas the maximal quantum yield (F_v /F_m) was determined during dark periods. Increases in …

Effects Of Exogenous Ketone Therapy On Performance, Cardiorespiration, And Seizure Genesis During Exposure To Hbo2 In The Sprague Dawley Rat, Nicole M. Stavitzski

USF Tampa Graduate Theses and Dissertations

Hyperbaric oxygen (HBO2) is used for clinical HBO2 therapy and in undersea and aerospace medicine. HBO2 is a humanmade extreme environment and protracted exposures can cause several adverse physiological effects on the body. For example, HBO2 increases the partial pressure of oxygen (PO2) in the body leading to redox stress. Redox stress is, in part, a cause of oxygen toxicity that manifests as seizures in its most severe form (central nervous system oxygen toxicity, CNS-OT). This dissertation focuses on strategies to be employed specifically for the warfighter breathing HBO2. Currently, the only way to prevent CNS-OT is to lower the …

The Ecological Role Of Cassiopea In Shallow Mangrove Habitats, David Marcel Durieux

USF Tampa Graduate Theses and Dissertations

Upside-down jellyfish, Cassiopea sp., can be locally abundant in shallow mangrove habitats throughout the tropics and subtropics. Unlike other jellyfish, Cassiopea sp. are epibenthic. Due to this unique lifestyle and their ability to achieve high population densities, an understanding is needed of their ecological impacts both individually and in aggregations, particularly given that Cassiopea sp. ranges are expanding poleward due to global climate change. We quantified the fluid flow produced by Cassiopea sp. feeding currents and found that an average-sized Cassiopea sp. can transport over 200 l/h of water in the vertical excurrent jet of their feeding current. Populations of …

Moving In Fluid: Exploring How Fishes Manipulate Water To Swim Efficiently, Nils B. Tack

USF Tampa Graduate Theses and Dissertations

Moving through a dense fluid such as water presents some unique challenges to minimizing energy use and maximizing performance (i.e., speed). Due to animal-fluid interactions during swimming (drag and thrust production) fish have evolved a variety of morphological structures and locomotor mechanisms. For instance, fish rely on body bending and/or fins to interact with the surrounding water such that energy can be transferred to generate thrust. Typically, this synergy promotes morphologies and behaviors aimed at enhancing propulsive efficiency and/or minimizing metabolic activity to lessen the cost of transport (COT). This work focuses on quantifying the energetic and hydromechanical benefits of …

Unraveling The Role Of Novel G5 Peptidase Family Proteins In Virulence And Cell Envelope Biogenesis Of Staphylococcus Aureus, Stephanie M. Marroquin

USF Tampa Graduate Theses and Dissertations

Virulence factors and the bacterial cell envelope are two important components in S. aureus pathogenesis and survival. More importantly, understanding the regulation of these cellular processes is crucial to further understanding and combating this successful pathogen. To date, numerous factors have been identified as playing a role in the regulation of Agr activity in S. aureus, including transcription factors, antisense RNAs, and host elements. Herein we investigate the product of SAUSA300_1984 (termed MroQ), a transmembrane G5 peptidase family protein, as a novel effector of this system. Using a USA300 mroQ mutant we observed a drastic reduction in proteolysis, hemolysis, and …

Ecology And Diversity Of Boletes Of The Southeastern United States, Arian Farid

USF Tampa Graduate Theses and Dissertations

The boletes are conspicuous stipito-pileate macrofungi that are generally defined by their tubulose hymenophores. Molecular phylogenetic analyses have informed extensive taxonomic revisions across the boletes. Despite this, the boletes in the southeastern USA have been largely absent from the literature. This dissertation seeks to understand the microbiome inhabiting the tuberculate ectomycorrhizae of the bolete Hemileccinum rubropunctum, and addresses taxonomic revisions of boletes found in the Boletaceae and Suillaceae. The introduction provides a brief background on boletes, as well as our understanding of tuberculate ectomycorrhizae. The second chapter seeks to understand the composition of the microbiome tuberculate ectomycorrhizae of H. rubropunctum …

Metastatic Mat Phenotype Driven By Noncanonical Epha2 Signaling In Melanoma, Chao Zhang

USF Tampa Graduate Theses and Dissertations

Acquired BRAF/MAPK/extracellular signal‒regulated kinase inhibitor resistance in melanoma results in a new transcriptional state associated with an increased risk of metastasis. In this study, we identified noncanonical ephrin receptor (Eph) EphA2 signaling as a driver of the resistance-associated metastatic state. We used mass spectrometry‒based proteomic and phenotypic assays to demonstrate that the expression of active noncanonical EphA2-S897E in melanoma cells led to a mesenchymal-to-amoeboid transition driven by Cdc42 activation. The induction of mesenchymal-to-amoeboid transition promoted melanoma cell invasion, survival under shear stress, adhesion to endothelial cells under continuous-flow conditions, increased permeability of endothelial cell monolayers, and stimulated melanoma transendothelial cell …

Evolutionary Mechanisms For Host Resistance To Tumor Growth And Subsequent Cancer Cell Counter-Adaptations, Arig Ibrahim Hashim

USF Tampa Graduate Theses and Dissertations

Cancer is well-recognized as an evolutionary system, as first proposed by Cairns and Nowell more than 60 years ago. In an evolutionary context, cancers growing in vivo typically consist of heterogeneous subpopulations of cells that interact with each other and with host cells through selection forces operating at many temporal and spatial scales. Moreover, the tumor environment comprises more than just cancer cells; it includes a rich cancer stroma and cancer-driving molecules such as cytokines and metabolites. The tumor’s environment comprises intratumoral heterogeneity that often leads to therapy resistance attributed to the essential roles of many genetic and nongenetic mechanisms. …

The Multifaceted Role Of Ccar-1 In The Alternative Splicing And Germline Regulation In Caenorhabditis Elegans, Doreen Ikhuva Lugano

USF Tampa Graduate Theses and Dissertations

The Cell Division Cycle and Apoptosis Regulator (CCAR) family members are an enigmatic family of proteins regulating metabolism, cancer, apoptosis, DNA damage, and stress. Mammals have CCAR family members, CCAR1 and CCAR2/DBC1, which evolved from the founding family member CCAR-1/LST-3 expressed in Caenorhabditis elegans. Several studies have shown the importance of understanding these proteins' function in standard and altered physiological processes. Our studies aim to understand the genome-wide alternative splicing and germline regulation of Caenorhabditis elegans CCAR-1 in normal and heat shock conditions. Recently, mammalian CCAR family member CCAR2/DBC1 regulates the alternative splicing by forming a complex with ZNF326. This …

Screening Next-Generation Fluorine-19 Probe And Preparation Of Yeast-Derived G Proteins For Gpcr Conformation And Dynamics Study, Wenjie Zhao

USF Tampa Graduate Theses and Dissertations

GPCR regulates numerous diverse physiological processes relevant to diabetes, obesity, Alzheimer's diseases, and several central nervous system disorders and targets proteins in signaling pathways. It has created nearly 200 billion profits from its derivative drugs in 2018. There are near 400 structures of over 70 GPCRs have been resolved by X-ray crystallography, cryo-electron microscopy, and NMR spectroscopy. One of the current challenges that remain in the conformational transition and dynamics study using NMR spectroscopy is to obtain sufficient quantities of the G proteins and GPCRs. Pichia pastoris has shown its tremendous promise in expressing the GPCRs in a high yield, …

Evolution Of Targeted Therapy Resistance In Eml4-Alk Positive Non-Small Cell Lung Cancer, Robert Vander Velde

USF Tampa Graduate Theses and Dissertations

Targeted therapies have emerged as potent treatments that lead to the remission of many tumors. However, they rarely cure cancers in advanced, metastatic settings. This is due to the evolution of resistance, which in turn can be ascribed to the survival of small subpopulations of tolerant and/or resistant cells. Here we investigated the evolution of resistance to EML4-ALK inhibitors in non-small cell lung cancer (NSCLC) and demonstrated that resistance evolves gradually, from unique pre-treatment sub-populations, as multiple resistance mechanisms accumulate in a Darwinian fashion. Despite accumulating multiple changes, cells evolved, in parallel, toward similar inhibitor specific phenotypes. Evolving cells have …

Phenotypic Diversity And Costs Of Early Hatching In Lizards, Zachary Winstead

USF Tampa Graduate Theses and Dissertations

Early hatching is a form of environmentally cued hatching in which embryos can emerge early to improve chances of survival and is considered a means of antipredator defense. Early hatching as a response to predation has been well documented in amphibians, but its prevalence among other animal groups is unknown. Moreover, any trade-offs between early hatching and other traits, and thus survival, are not well understood. There is anecdotal evidence that lizards exhibit early hatching behavior, but quantitative evidence is limited to one study. In the present study, I tested for the presence of early hatching in six species of …

Metabolic Rate, Critical Oxygen Partial Pressure, And Oxygen Supply Capacity Of Farfantepenaeus Duorarum At Their Lower Thermal Limit, Alexandra L. Burns

USF Tampa Graduate Theses and Dissertations

Temperature and environmental oxygen availability affect oxygen supply and demand in ectotherms, which are hypothesized to control the geographic limits of many marine species. The oxygen supply capacity (α) is calculated from commonly measured metabolic traits, including the standard metabolic rate (SMR) and critical oxygen partial pressure at SMR (Pcrit). It may be used to estimate the metabolic capacity and aerobic scope across changes in temperature and oxygen partial pressures as α reflects adaptations of the cardiorespiratory system to meet maximum energy demands at a given oxygen partial pressure (PO2). In this study, α was measured for the Tampa Bay …

A Review Of Marine Turtle Orientation And Artificial Lighting Impacts With Novel Results From Florida’S Gulf Coast, Andrea M. Fisher

USF Tampa Graduate Theses and Dissertations

Artificial light (i.e. unnatural light emitting from a human-made source) is one of the most extensively distributed, and least managed, type of anthropogenic pollution. Due to the disproportionally high rates of urbanization in critical coastal ecosystems, species, like marine turtles that use beach habitat for nesting activities, are especially vulnerable. Marine turtles employ the use of multiple visual cues (e.g. wavelength, intensity, background illumination, and dark silhouettes) to conduct sea-finding behavior and different variations in cue usage exist across species and geographic location. During nesting and emergence activities, orientation can be interrupted and manipulated by artificial lighting resulting in lower …

Examining The Presence Of A Possible Species Complex Of Octopus Joubini (Cephalopoda: Octopodidae) In The Eastern Gulf Of Mexico, Haley Holloway

USF Tampa Graduate Theses and Dissertations

The Pygmy Octopus Octopus joubini (Robson, 1929) is a small, shallow water species found throughout the Gulf of Mexico (GoM), western Atlantic Ocean and the northeastern Caribbean Sea (Mather, 1982; Jereb & Roper, 2014; Judkins, 2009). This species is believed to belong to a complex based upon morphological features including arm length, web depth, sucker size, egg size, hatchling ecology, and chromatophore coloration. It has been proposed that Octopus mercatoris, another pygmy species found in the GoM, may belong in this complex; however, no analyses have been performed to verify this claim. The present study incorporated morphological comparisons with …

Cetacean Maternal Investment: Importance In Conservation Across Species And Drivers For Interspecific Altruism, Christopher Klein

USF Tampa Graduate Theses and Dissertations

Cetacean maternal investments can be useful for conservation management as well as examining behaviors such as interspecific altruism in the humpback whale, Megaptera novaeangliae. Cetaceans are among the most threatened group of marine mammals. In the second chapter, maternal investments across ~90 species/subspecies of Cetacea were analyzed to aid in the understanding of recovery/replacement for conservation and management. Using Principal Components Analysis (PCA), a relative maternal-investment index for 41 cetacean species was built. The maternal-investment index was a composite of four maternal-investment variables, the duration of gestation, lactation, calving intervals, and the number of reproduction years per female per species. …

Home Range Area, Overlap, Homing Behavior And Movement Patterns In Plestiodon Reynoldisi, Paul Wieczorek Ii

USF Tampa Graduate Theses and Dissertations

Home range and home range overlap information are crucial to create management plans for species of conservation concern. It provides information as to how much land a viable population needs to survive. The South Florida Multi-Species Recovery Plan highlights the need for home range and movement information for Plestiodon reynoldsi (Florida Sand Skink), a threatened lizard species precinctive to Florida Scrub habitat. We investigated home range sizes, their relationship with SVL and mass, home range overlap, homing behavior, and movement patterns of the Florida Sand Skink (FSS) and over a three-year period in the Lake Wales Ridge National Wildlife Refuge. …

Fire Severity Effects On Herpetofaunal Diversity In Florida Scrub Communities Of The Lake Wales Ridge, Michelle Lindsay

USF Tampa Graduate Theses and Dissertations

Fires, either natural or prescribed, are essential for conserving pyrogenic ecosystems; however, climate change is predicted to increase fire severity that could negatively impact species diversity. Reptile and amphibian species may be particularly at risk given they are ectothermic species. The objective of this study was to better understand the impacts of fire severity on the herpetofaunal communities of the Florida scrub habitats, which is an imperiled ecosystem that sustains over two-thirds of listed reptiles and amphibians in Florida. We conducted a field-based study to test taxonomic and functional herpetofaunal diversity differences across four varying fire severities: unburned, low, medium …

The Science Of Guessing: Critiquing Ancestral Estimation Through Computer Generated Statistical Analysis Within Forensic Anthropology In A Real-World Setting, Christopher J. Turner

USF Tampa Graduate Theses and Dissertations

Research on current methods of ancestral estimation must reflect on biological heritage to aid in human identification. Using modern craniometrics methods, how do individuals with a varied biological history affect ancestral estimation? Today, the most used and reliable methods for craniometrics analysis for ancestral estimation in forensic anthropology are computer programs. Two programs are analyzed in this study, Fordisc 3.0 and 3D-ID. The analysis of these computer programs goes beyond the controlled environment provided by an osteological collection. These remains of individuals were unidentified, only to be identified later, through academic research, police work, and public outreach. The selection of …

Ecophysiological Responses Of Two Closely Related Epigean And Hypogean Niphargus Species To Hypoxia And Increased Temperature: Do They Differ?, Tatjana Simčič, Boris Sket

International Journal of Speleology

Ecological performance of animals depends on physiological and biochemical processes that are adjusted to the environment. The responses to hypoxia or anoxia have been frequently studied in subterranean aquatic organisms in order to find potential adaptations to restrict oxygen conditions occurring in the underground habitats. However, some previous studies have compared phylogenetic distant epigean and hypogean species or the epigean and hypogean populations of the same species due to little chance to compare closely related epigean and hypogean species. Therefore, in this study, we compared the effects of exposure to hypoxia, followed by reoxygenation, and increased temperature on oxygen consumption, …

Epigenetic Potential In An Introduced Passerine, Haley E. Hanson

USF Tampa Graduate Theses and Dissertations

Epigenetic modifications play a critical role in numerous processes throughout the lifetime of an organism by influencing gene regulation. Responsive to both endogenous cues and external stimuli, epigenetic modifications are key mechanisms underlying phenotypic plasticity. Epigenetic potential, or the capacity for phenotypic plasticity mediated by epigenetic modifications, can be encoded within the genome via genetic variation underlying aspects of epigenetic modifications. For example, one type of epigenetic modification, DNA methylation, predominately occurs at CpG motifs in vertebrates. The number of CpG sites within the genome then represents the capacity for DNA methylation to occur and is one form of epigenetic …

Quantifying The Gametogenic Cycle And Reproductive Efforts In The Eastern Oyster (Crassostrea Virginica) In Florida Estuaries, Nicole Patrice Maloney

USF Tampa Graduate Theses and Dissertations

Oyster populations from six estuaries in Florida were sampled monthly from January to December of 2018 for reproduction and health analysis. Sites were located in Apalachicola Bay, Caloosahatchee River estuary, Lake Worth lagoon, Loxahatchee River estuary, St. Lucie estuary, and Tampa Bay. Oysters monitored for analysis in South Florida (Loxahatchee River estuary, St. Lucie estuary, and Caloosahatchee River estuary) were chosen as they are a part of a monitoring component of the Comprehensive Everglades Restoration Plan. These estuaries are highly influenced by freshwater input from Lake Okeechobee and other river basins. Like the South Florida sites Apalachicola Bay is also …

Nest Site Choice As A Potential Climate Response In The Gopher Tortoise (Gopherus Polyphemus), A Threatened Species, Meghan Craft

USF Tampa Graduate Theses and Dissertations

Climate warming is expected to continue in coming decades, posing a threat to species worldwide. While some species may be able to shift their ranges in the pursuit of cooler temperatures, a large portion of species may have to find ways to adapt to warmer conditions in situ. Oviparous reptiles may be able to buffer against rising temperatures by altering nest site choice. In this study, I quantified nest site choice and its thermal consequences in a population of the gopher tortoise (Gopherus polyphemus) in southwestern Florida. I found marked variation in the openness of selected nest sites, …

The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes

USF Tampa Graduate Theses and Dissertations

Objectives: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations.

Materials and methods: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy–Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables.

Results: Many of the samples have extremely high frequencies of the T allele (q̄ = 0.62, median = 0.66). In this region, the frequency of the T …

Effect Of Temperature On Growth And Gene Expression In The Marine Diatom, Thalassiosira Pseudonana, John M. Foster

USF Tampa Graduate Theses and Dissertations

Diatoms are unicellular, eukaryotic, photosynthetic algae responsible for the production of 20% of our atmospheric oxygen. Diatoms contribute to several important biogeochemical functions. Diatoms contribute to the carbon cycle, sequestering carbon and forming oxygen as a product of photosynthesis. Moreover, by converting abiotic forms of energy such as sunlight into organic compounds (i.e., sugars, starches and lipids), primary producers including diatoms, plants, and phytoplankton feed organisms at higher trophic levels. Consequently, changes in temperature, light intensity, nutrients, salinity and other stress factors that affect primary producers can generate a potentially catastrophic ripple effect at higher trophic levels In this study …

Shorebird Response To Human-Induced Changes At Three Pinellas County Beaches, Rebecca J. Ruthberg-Campagna

USF Tampa Graduate Theses and Dissertations

Worldwide, shorebird habitat is being destroyed and degraded by development and sea level rise. Shorebirds depend on availability of pristine, undisturbed coastal habitats for resting and feeding during migration as well as for reproduction. Migratory shorebirds using the East Atlantic Flyway visit the Gulf of Mexico Beaches of Pinellas County, Florida as a stopover site during Fall and Spring migration. In addition to hosting migratory species, Pinellas County beaches are home to several year-round resident species that breed during Summer. Pinellas County is the most densely populated county in Florida, and its Gulf Coast is heavily developed with commercial and …

Global Economic Costs Of Aquatic Invasive Alien Species, Ross N. Cuthbert, Zarah Pattison, Nigel G. Taylor, Laura Verbrugge, Christophe Diagne, Danish A. Ahmed, Boris Leroy, Elena Angulo, Elizabeta Briski, César Capinha, Jane A. Catford, Tatenda Dalu, Franz Essl, Rodolphe E. Gozlan, Phillip J. Haubrock, Melina Kourantidou, Andrew M. Kramer, David Renault, Ryan J. Wasserman, Franck Courchamp

Integrative Biology Faculty and Staff Publications

Much research effort has been invested in understanding ecological impacts of invasive alien species (IAS) across ecosystems and taxonomic groups, but empirical studies about economic effects lack synthesis. Using a comprehensive global database, we determine patterns and trends in economic costs of aquatic IAS by examining: (i) the distribution of these costs across taxa, geographic regions and cost types; (ii) the temporal dynamics of global costs; and (iii) knowledge gaps, especially compared to terrestrial IAS. Based on the costs recorded from the existing literature, the global cost of aquatic IAS conservatively summed to US$345 …

The Genomic Processes Of Biological Invasions: From Invasive Species To Cancer Metastases And Back Again, Fargam Neinavaie, Arig Ibrahim-Hashim, Andrew M. Kramer, Joel S. Brown, Christina L. Richards

Integrative Biology Faculty and Staff Publications

The concept of invasion is useful across a broad range of contexts, spanning from the fine scale landscape of cancer tumors up to the broader landscape of ecosystems. Invasion biology provides extraordinary opportunities for studying the mechanistic basis of contemporary evolution at the molecular level. Although the field of invasion genetics was established in ecology and evolution more than 50 years ago, there is still a limited understanding of how genomic level processes translate into invasive phenotypes across different taxa in response to complex environmental conditions. This is largely because the study of most invasive species is limited by information …

Deep Learning For Supervised Classification Of Temporal Data In Ecology, César Capinha, Ana Ceia-Hasse, Andrew M. Kramer, Christiaan Meijer

Integrative Biology Faculty and Staff Publications

Temporal data is ubiquitous in ecology and ecologists often face the challenge of accurately differentiating these data into predefined classes, such as biological entities or ecological states. The usual approach consists of transforming the time series into user-defined features and then using these features as predictors in conventional statistical or machine learning models. Here we suggest the use of deep learning models as an alternative to this approach. Recent deep learning techniques can perform the classification directly from the time series, eliminating subjective and resource-consuming data transformation steps, and potentially improving classification results. We describe some of the deep learning …

Deep Learning For Supervised Classification Of Temporal Data In Ecology, César Capinha, Ana Ceia-Hasse, Andrew M. Kramer, Christiaan Meijer

Integrative Biology Faculty and Staff Publications

Temporal data is ubiquitous in ecology and ecologists often face the challenge of accurately differentiating these data into predefined classes, such as biological entities or ecological states. The usual approach consists of transforming the time series into user-defined features and then using these features as predictors in conventional statistical or machine learning models. Here we suggest the use of deep learning models as an alternative to this approach. Recent deep learning techniques can perform the classification directly from the time series, eliminating subjective and resource-consuming data transformation steps, and potentially improving classification results. We describe some of the deep learning …