Life Sciences Commons^™

A Comparative Genomics Exploration Of Inter-Partner Metabolic Signaling In The Coral-Algal Symbiosis, Katherine E. Dougan

FIU Electronic Theses and Dissertations

At the foundation of coral reef ecosystems is the symbiosis between the coral host and its microbial community, particularly its photoautotrophic algae from the family Symbiodiniaceae. As a symbiosis centered around nutritional exchange, determining the mechanisms involved in the maintenance of this cooperative exchange is central to understanding how it breaks down. As the nutritional transfer primarily consists of sugars, this work first focuses on the cnidarian insulin signaling pathway, an evolutionarily important metazoan pathway involved in diverse functions, most notably metabolism. This dissertation unveiled 360 putative cnidarian insulin-like peptides (cnILPs) from existing transcriptomic datasets, where they were previously missed …

Bacterial Mechanisms Of Toxicity And Resistance To Organoarsenicals, Luis D. Garbinski

FIU Electronic Theses and Dissertations

Arsenic is a toxic element prevalent in the environment since the origin of life on Earth. Bacteria evolved in an arsenic-rich environment, where they developed ways to both overcome arsenic toxicity and harness it to compete with other organisms. These mechanisms include chemical modifications (e.g. oxidation, methylation), degradation, and efflux. The goal of this dissertation is to better characterize these mechanisms, illuminating the arsenic biogeocycle and allowing us to harness organoarsenical toxicity for novel antibiotics. A goal of my research was to elucidate the antibiotic properties of MAs(III), which is synthesized by bacteria to thrive over other bacteria, by identifying …

Production And Characterization Of Twelve Different Biochars And Evaluating Their Effects On Soil Health And Plant Growth, Shagufta Gaffar

FIU Electronic Theses and Dissertations

Biochar has been a topic of growing interest in the scientific community. It is a product derived from carbon rich organic materials through the process of pyrolysis. It has received wide attention as a means to improve soil fertility and crop productivity, absorb pollutants in soil, and sequester carbon to mitigate climate change. Recent research on biochar explores its impacts on the environment with particular focus on use as a soil amendment in agriculture. Biochar produced from different biomass and under different production process effects the environmental and agronomic impacts of its application in different ways. This means biochar can …

Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter

FIU Electronic Theses and Dissertations

This research investigates the distribution and population structure of crustaceans, endemic to anchialine systems in the tropical western Atlantic focusing on cave-dwelling shrimp from the family Barbouriidae. Taxonomic and molecular tools (genetic and genomic) are utilized to examine population dynamics and the presence of phenotypic hypervariation (PhyV) of the critically endangered species Barbouria cubensis (von Martens, 1872). The presence of PhyV and its geographic distribution is investigated among anchialine populations of B. cubensis from 34 sites on Abaco, Eleuthera, and San Salvador, Bahamas. Examination of 54 informative morphological characters revealed PhyV present in nearly 90% (n=463) of specimens with no …

Long-Term And Seasonal Drivers Of Phytoplankton Assembly In A Subtropical Monomictic Lake, Kristy Lee Sullivan

FIU Electronic Theses and Dissertations

Seasonal phytoplankton dynamics in lakes are highly sensitive physicochemical changes in the water column. As climate-driven frequency and variability of precipitation increases, lakes may experience increased inputs of allochthonous organic matter and nutrients through pulsed rain events. The resultant effects of lake physicochemistry on phytoplankton seasonal succession and assemblage are poorly understood. In the current study, the phytoplankton assemblage of a subtropical monomictic lake was examined in the context of natural interannual oscillations in allochthonous dissolved organic carbon and nutrient inputs resulting in prolonged clear-water and dark-water phases over a 14-year period. Differences in water clarity and nutrient concentrations among …

Carbapenem-Resistant Enterobacteriaceae (Cre): Epidemiology, Duration Of Carriage, And Progression To Infection In A Large Healthcare System In Miami, Fl, Adriana Jimenez

FIU Electronic Theses and Dissertations

Carbapenem-resistant Enterobacteriaceae (CRE) are multidrug-resistant organisms (MDRO) considered by the CDC as an urgent public health threat that is spreading globally. Little is known about the epidemiology of CRE in Miami, FL. The purpose of this dissertation was to 1) Evaluate trends in the epidemiology of CRE among patients admitted to the acute care facilities of the largest healthcare system in Miami, FL between 2012 and 2016, 2) Identify factors associated with progressing to infection among patients colonized with carbapenemase-producing Enterobacteriaceae (CPE), and 3) Determine the duration of CPE carriage and factors associated with long-term carriage in our cohort.

A …

Development Of A Dna Methylation Multiplex Assay For Body Fluid Identification And Age Determination, Quentin Gauthier

FIU Electronic Theses and Dissertations

For forensic laboratories, the determination of body fluid origin of samples collected at a crime scene are typically presumptive and often destructive. However, given that in certain cases the presence of DNA is not in dispute and rather where the DNA came from is of primary concern, new methodologies are needed. Epigenetic modifications, such as DNA methylation, affect gene expression in every cell of every mammal. These DNA methylation patterns typically are observed as the addition of a methyl group on the 5’ carbon of a cytosine followed by guanine (CpG). Methylation patterns have been observed to change in response …

The Effect Of Emotional State, Interoception, Intuitive Eating, And Self-Regulation On The Energy Intake Of College Students, Padideh Haddadian Lovan

FIU Electronic Theses and Dissertations

College students are known to be susceptible to weight gain. Transitioning to college brings new stresses and challenges which may lead to unhealthy eating behaviors and weight gain. There are multiple factors which have been attributed to exacerbating determinants for college weight gain including eating in the absence of hunger, lack of self-regulation, and emotional eating. As researchers have become more aware of the disadvantages of dieting and restricted eating, cognitive related behaviors, as a way to control weight, have gained more attention recently.

The aim of this study is to examine the association between internal bodily signals of hunger …

Investigating The Population Dynamics Of An Avian Apex Predator Across An Urban Gradient, Donna Marain

FIU Electronic Theses and Dissertations

Predators are often the focus of conservation efforts. They can be useful sentinel species, umbrella species, and flagship species. Predators can also be the first guild lost when ecosystems are under stress, especially from anthropogenic land-use change. Avian predators (raptors) can be an exception to this trend, filling the role of apex predators across the urban gradient. South Florida contains the Everglades ecosystem and one of the fastest growing human populations in the country. In the current study, I investigated the population dynamics of South Florida’s most abundant hawk: the Red-shouldered Hawk (Buteo lineatus, RSHA) across the urban …

Back From The Brink?: Rebounding And Remnant Amphibian Populations In A Pathogen Enzootic Environment, Alexander D. Shepack

FIU Electronic Theses and Dissertations

The Anthropocene epoch has been marred by a global biodiversity crisis and the advent of Earth’s sixth mass extinction. Amphibians, the most threatened vertebrate taxa, have become the poster children for this sixth mass extinction. The pathogenic fungus Batrachochytrium dendrobatidis has been blamed for many of declines and extinctions seen in amphibians. The now panglobal Bd causes the disease chytridiomycosis in a large number of amphibian species and has been linked to population crashes in Central and South America, Australia, Europe, and the United States. Now enzootic around the world, amphibian populations continue to confront Bd in a long-term battle …

Systematic Studies In Myrtaceae Of The Greater And Lesser Antilles, Jonathan A. Flickinger

FIU Electronic Theses and Dissertations

The Myrtaceae, or myrtle family, are a group of flowering trees and shrubs represented in the Americas by over 2000 species of the predominantly Neotropical tribe Myrteae. Recent progress on the challenging systematics of the group has been achieved through molecular phylogenetics, but few of the almost 500 species endemic to the islands of the Greater and Lesser Antilles in the Caribbean have been included in either phylogenetic or revisionary studies. The purpose of my dissertation is therefore to contribute to the description and phylogenetic classification of Antillean Myrtaceae. The first study describes Eugenia walkerae, a new species of …

Exploration Of The Role Of Microbiome Structure, Metabolism, And Modification In Black Band Disease Etiology, Patricia Waikel

FIU Electronic Theses and Dissertations

The coral microbiome plays an integral role in coral health. Modification of the microbiome is thought to alter susceptibility to disease. Black Band Disease (BBD), is polymicrobial, mat forming, and affects reef building coral globally. Dominated by the cyanobacterium Roseofilum reptotaenium, it has been noted to increase in virulence with increasing temperatures, making BBD of particular concern in the face of climate change-induced warming seas. The active sulfur cycle of BBD makes dimethylsulfoniopropionate (DMSP), a widely available source of sulfur in the marine environment, of particular interest in the study of BBD. Traditional infection studies require field collection and …

Causality In Microbiomes, Md Musfiqur Rahman Sazal

FIU Electronic Theses and Dissertations

No abstract provided.

Structure Function Relationship In Hexacoordinate Heme Proteins: Mechanism Of Globin X Interactions With Exogenous Ligands And Ligand Accessiblity In Cytoglobin And Neuroglobin, Ruipeng Lei

FIU Electronic Theses and Dissertations

Cytoglobin (Cygb), neuroglobin (Ngb), and globin X (GbX) belongs to recently discovered members of the vertebrate globin family, they carry a heme prosthetic group that can reversibly bind exogenous ligands such as CO, NO and O₂. Although the physiological functions of Cygb, Ngb and GbX are still under debate, several possible physiological functions for these proteins were proposed. Cytoglobin was reported to participate in lipid-based signaling and to stabilize the tumor suppressor p53 upon DNA damage, which imply its anti-cancer role. Neuroglobin was shown to interact with α-subunit of the heterotrimeric G protein as well as cytochrome c …

3d Architectural Analysis Of Neurons, Astrocytes, Vasculature & Nuclei In The Motor And Somatosensory Murine Cortical Columns, Jared Leichner

FIU Electronic Theses and Dissertations

Characterization of the complex cortical structure of the brain at a cellular level is a fundamental goal of neuroscience which can provide a better understanding of both normal function as well as disease state progression. Many challenges exist however when carrying out this form of analysis. Immunofluorescent staining is a key technique for revealing 3-dimensional structure, but subsequent fluorescence microscopy is limited by the quantity of simultaneous targets that can be labeled and intrinsic lateral and isotropic axial point-spread function (PSF) blurring during the imaging process in a spectral and depth-dependent manner. Even after successful staining, imaging and optical deconvolution, …

Structure, Control, And Communication Of Collective Animal Behavior In Dynamic Environments, Ivan Ignacio Rodriguez-Pinto

FIU Electronic Theses and Dissertations

Collective behavior in animal aggregations is highly complex and spans multiple spatial scales, across a wide range of environmental conditions. In socially active fish, aggregation into schools is a widespread adaptation that confers a variety of safety benefits. The emergent patterns exhibited by collectively behaving fish schools may be influenced by biotic (i.e. predation) or abiotic (i.e. habitat complexity, turbidity) factors in the local environment. Our knowledge of the ways and extent to which environment variability affects schooling behavior at the collective level is currently limited. In this dissertation, I investigated whether environmental factors influenced the collective behavior of fish …

Deciphering The Micrornaome In Hiv Associated Lung Comorbidities, Rajib Kumar Dutta

FIU Electronic Theses and Dissertations

Chronic Respiratory diseases like chronic obstructive pulmonary disease (COPD), pulmonary hypertension, asthma, and pneumonia are emerging as significant comorbidities in people living with HIV in the combination antiretroviral therapy (cART) era. HIV is an independent risk factor for these diseases independent of tobacco smoke, and cigarette smoking exacerbates outcomes in HIV patients. Both tobacco smoke and HIV infection suppress nasal mucociliary clearance (MCC) as well as bronchial MCC, a primary innate defense mechanism in the airway. Optimal MCC depends on airway surface liquid (ASL) lining the airway epithelium that facilitates ciliary beating to clear the mucus. Attenuation of any component …

Development Of Prefrontal Structure And Connectivity In Typical Children And Children With Adhd: Association With Language And Executive Function, Dea Garic

FIU Electronic Theses and Dissertations

The structure and connectivity of the prefrontal cortex has been extensively studied for its contribution to language and executive function (EF) development, but many questions still remain whether its microstructural tissue properties can reliably predict behavioral outcomes in very young typically and atypically developing populations. In particular, the bilateral frontal aslant tract (FAT) has garnered increasing interest with respect to its potential association with both language and EF, but has yet to be examined in childhood attention disorders, such Attention Deficit Hyperactivity Disorder (ADHD). At the same time, with advances in diffusion weighted imaging (DWI), new diffusion models offer more …

Beyond Predation: How Do Consumers Mediate Bottom-Up Processes In Ecosystems?, Bradley Austin Strickland

FIU Electronic Theses and Dissertations

By eating and scaring prey, predators can exert strong effects on communities and ecosystems. In addition, some animals may physically alter habitats and may recycle nutrients through digestion, both of which affect resources available to producers. Bottom-up effects initiated by large predators have not been well-studied and could prove to be important for understanding food webs and how ecosystems function. American alligators (Alligator mississippiensis) are abundant mobile predators that are capable of engineering aquatic habitats by moving organic material across ecosystem boundaries and creating and maintaining alligator ponds. In this dissertation, I documented the scale of ecological impacts …

Dna Base Excision Repair Modulates Dna Repeat Instability And Non-B Form Dna Structures, Eduardo E. Laverde

FIU Electronic Theses and Dissertations

The human genome is constantly attacked by endogenous and exogenous sources of DNA damage that generates DNA base lesions and strand breaks leading to genome instability, cell death, and diseases. To combat these adverse effects, cells have evolved a robust DNA repair mechanism called “the DNA base excision repair (BER),” which efficiently removes DNA lesions maintaining genome stability. However, its underlying molecular mechanisms remain to be elucidated. In my dissertation research, I explored the molecular mechanism by which BER modulates trinucleotide repeats (TNR) by processing non-B form structures such as hairpins and R-loops through the coordination among BER enzymes and …

The Effect Of Vitamin D3 Supplementation On Advanced Glycation End Products, (Ages) And Soluble Receptor, (Srage) In African Americans And Hispanics With Type 2 Diabetes And Vitamin D Insufficiency/Deficiency, Justina Serwaah Owusu

FIU Electronic Theses and Dissertations

There is a high burden of diabetes and its related complications globally. Advanced Glycation End Products (AGEs) and their receptors have been implicated in complications and mortality related to type 2 diabetes (T2D). Vitamin D deficiency, prevalent in persons with T2D, increases oxidative stress and inflammation that promotes the formation of AGEs.

This study assessed the relationship between sRAGE and AGEs and risk of cardiovascular diseases (CVD) and the effect of vitamin D3 supplementation on levels of AGEs and soluble receptor (sRAGE) in adults with hypovitaminosis D. African Americans and Hispanics (n=64) were recruited in Miami and were supplemented with …

Phylogenetic And Transcriptomic Analyses Of Vision In Two Cave Adapted Crustaceans, Asellus Aquaticus (Isopoda: Asellidae) And Niphargus Hrabei (Amphipoda: Niphargidae)., Jorge L. Perez Moreno

FIU Electronic Theses and Dissertations

The unique characteristics of aquatic caves and of their predominantly crustacean biodiversity nominate them as ideal study subjects for evolutionary biology. The present dissertation capitalizes on a perfect natural experiment, the Molnar Janos thermal cave system in Budapest, Hungary. This intricate freshwater cave system and the immediately adjacent Malom Lake present the ideal opportunity to address questions of colonization, adaptation, and evolution. Despite marked environmental differences between the cave and surface waters, both localities are inhabited by natural populations of two emerging model cave species, the isopod Asellus aquaticus and the amphipod Niphargus hrabei. In the present dissertation, I …

Scalable Profiling And Visualization For Characterizing Microbiomes, Camilo Valdes

FIU Electronic Theses and Dissertations

Metagenomics is the study of the combined genetic material found in microbiome samples, and it serves as an instrument for studying microbial communities, their biodiversities, and the relationships to their host environments. Creating, interpreting, and understanding microbial community profiles produced from microbiome samples is a challenging task as it requires large computational resources along with innovative techniques to process and analyze datasets that can contain terabytes of information.

The community profiles are critical because they provide information about what microorganisms are present in the sample, and in what proportions. This is particularly important as many human diseases and environmental disasters …

Understanding, Quantifying, And Reducing Bias In Fisheries-Independent Visual Surveys, James Kilfoil

FIU Electronic Theses and Dissertations

Understanding spatiotemporal changes in populations is vital for conservation managers to assess current recovery efforts, determine future conservation priorities, and forms the basis to explore complex ecological questions. In fisheries, these data have traditionally been collected using fisheries-independent surveys that rely on extractive sampling practices (e.g., longlines, gillnets, trawls). However, with the growing availability of low-cost, high-definition cameras, researchers are increasingly using visual surveys as a non-invasive alternative. Camera surveys have a number of advantages including their archivable data, and offer insights into species habitat use and behavior. However, the use of cameras has a number of inherent biases. Understanding, …

The Metabolic Ecology Of Tropical Amphibians Across An Elevational Gradient In The Andes Of Southeastern Peru, Michael R. Britton

FIU Electronic Theses and Dissertations

Metabolism is a fundamental biological process that determines the rate at which organisms process energy and materials, and determines the availability of resources for growth, maintenance and reproduction. Metabolic rates scale across levels of organization from cells to whole organisms and affect population, community, and ecosystem processes. Anthropogenic climate change and other environmental changes are predicted to have major impacts on the energetics of organisms that will be mediated through metabolic physiology. Tropical ectotherms, such as amphibians, may be among the most vulnerable to metabolic impacts of climate change as a result of being ectothermic, having high thermal sensitivity, and …