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Full-Text Articles in Life Sciences

The Ecology Of Extrafloral Nectar In Senna Mexicana Var. Chapmanii, Ian M. Jones Apr 2016

The Ecology Of Extrafloral Nectar In Senna Mexicana Var. Chapmanii, Ian M. Jones

FIU Electronic Theses and Dissertations

Extrafloral nectar (EFN) mediates food-for-protection mutualisms between plants and defensive insects. Senna mexicana var. chapmanii is a perennial legume native to the pine rockland habitats of south Florida. My dissertation focuses on how anthropogenic changes to the pine rocklands might affect EFN production by S. chapmanii, and the outcome of EFN mediated interactions. First, I investigated the influence of time of day, leaf damage, and leaf age on EFN production in S. chapmanii. Plants produced more nectar at night than during the day, and leaf damage resulted in increased EFN production. Furthermore, the response to leaf damage was …


A Study On The Dissolution Of Autunite Minerals By Facultative Bacteria In Bicarbonate Media, Sandra C. Herrera Landaez Apr 2016

A Study On The Dissolution Of Autunite Minerals By Facultative Bacteria In Bicarbonate Media, Sandra C. Herrera Landaez

FIU Electronic Theses and Dissertations

Uranium (U) is a key contaminant at the Hanford site. The formation of uranyl-phosphate bearing minerals such as autunite as a result of tripoliphosphate injections has been used as a U immobilization strategy. Bacteria are known as key factors governing the fate and transport of soil contaminants. This research evaluated the interaction of facultative bacteria Shewanella Oneidensis MR-1 with autunite mineral in bicarbonate-amended media solutions. The concentration of several elements such as U, calcium (Ca) and phosphorous (P) released as a result of autunite mineral biodissolution were determined as a function of time; changes in cell density and protein assay …


Controls On Benthic Microbial Community Structure And Assembly In A Karstic Coastal Wetland, Nicholas O. Schulte Mar 2016

Controls On Benthic Microbial Community Structure And Assembly In A Karstic Coastal Wetland, Nicholas O. Schulte

FIU Electronic Theses and Dissertations

The assembly mechanisms underlying microbial community abundance, biotic interactions, and diversity over space and time are unresolved, particularly in benthic microbial mats distributed along environmental gradients. Experimental enrichment of nutrient-limited microbial mats from the Florida Everglades along a nutrient subsidy-salinity stress gradient stimulated autotrophic and heterotrophic metabolism, growth, and diversity independent of autotroph-heterotroph interactions across treatments and space. These results suggest spatial segregation of autotrophic and heterotrophic components within mats. Considering only the diatom component of Everglades mats over space and time, the subsidy-stress gradient controlled diatom compositional turnover at broad spatial scales while environmental and dispersal-based processes structured diatom …


Turn Me On Or Off: A Study On Epigenetics And Merleau-Ponty In Angela Carter’S “The Lady Of The House Of Love”, Solsiree Lynn Skarlinsky Mar 2016

Turn Me On Or Off: A Study On Epigenetics And Merleau-Ponty In Angela Carter’S “The Lady Of The House Of Love”, Solsiree Lynn Skarlinsky

FIU Electronic Theses and Dissertations

This study aims to trace points of intersection between the too often divorced disciplines of literature, continental philosophy, and the hard sciences in Angela Carter’s “The Lady of the House of Love.” In short, this thesis will not only explore how such conversations surface within the short story, but will also serve as an explication of Maurice Merleau-Ponty’s philosophy of body and space, and the theory of epigenetics. Through these explications, the thesis itself will also gear one discipline towards the other as both theories intimately bind the environment with the body, and the body with the environment. Thus, …


Responses Of Four Non-Tidal Forest Communities Of The Florida Everglades To Hurricane Impact Over 21 Years, Jeremy L. May Mar 2016

Responses Of Four Non-Tidal Forest Communities Of The Florida Everglades To Hurricane Impact Over 21 Years, Jeremy L. May

FIU Electronic Theses and Dissertations

The regular occurrence of hurricane-associated winds has been an important factor in shaping the structure and composition of the forest ecosystems of the Florida Everglades. Forest communities in the Everglades are adapted to hurricane disturbances, but increased frequency and/or intensity of hurricanes may lead to decline or even collapse of these communities. The overall objective of this project is to understand the patterns, pace, and mechanisms of the recovery process to Hurricane Andrew damage in four Everglade forest communities: pinelands, hardwood hammocks, bayhead tree islands, and cypress domes. This study combines long- and short-term field measurements and experimental garden studies …


Consequences Of Anthropogenic And Global Change On Orchids: An Emphasis On Biotic Interactions, Jason L. Downing Mar 2016

Consequences Of Anthropogenic And Global Change On Orchids: An Emphasis On Biotic Interactions, Jason L. Downing

FIU Electronic Theses and Dissertations

Evidence suggests that human-driven changes to the earth are having clear and profound effects on many species, as well as the species with which they associate. Disruptions in the interactions between species can change the community structure, in turn changing the dynamics of entire ecosystems. The following dissertation examines how the impacts of climate change related events and invasive species may influence biotic interactions and impact orchid populations and range distributions. Here I quantify how orchid pollinators and mycorrhiza vary between species with different life histories, and between and within habitats. The results showed that orchids with wide range distributions …


The Individual And Interactive Effects Of Nitrogen And Phosphorus Enrichment On Coral Reefs, Andrew A. Shantz Mar 2016

The Individual And Interactive Effects Of Nitrogen And Phosphorus Enrichment On Coral Reefs, Andrew A. Shantz

FIU Electronic Theses and Dissertations

Human domination of global nutrient cycles is profoundly altering our planet. Yet on coral reefs, the effects of changing nutrient regimes have likely been over-simplified. This dissertation investigates the complexity of animal-nutrient interactions at the organismal level and explores how the outcomes of these interactions cascade through levels of biological organization. To do so, I examined the effects of nitrogen (N) and phosphorus (P) on corals and macroalgae, and how these effects in turn influenced reef communities and entire ecosystems. I show that P consistently increases coral growth rates while N has variable, often negative, effects on coral growth. The …


Protein-Ligand Interactions And Allosteric Regulation Of Activity In Dream Protein, Walter G. Gonzalez Mar 2016

Protein-Ligand Interactions And Allosteric Regulation Of Activity In Dream Protein, Walter G. Gonzalez

FIU Electronic Theses and Dissertations

Downstream regulatory antagonist modulator (DREAM) is a calcium sensing protein that co-assembles with KV4 potassium channels to regulate ion currents as well as with DNA in the nucleus, where it regulates gene expression. The interaction of DREAM with A-type KV4 channels and DNA has been shown to regulate neuronal signaling, pain sensing, and memory retention. The role of DREAM in modulation of pain, onset of Alzheimer’s disease, and cardiac pacemaking has set this protein as a novel therapeutic target. Moreover, previous results have shown a Ca2+ dependent interaction between DREAM and KV4/DNA involving …


Conjugated Polymer-Based Biomaterials Through Controlled Self-Assembly, Megan Twomey Mar 2016

Conjugated Polymer-Based Biomaterials Through Controlled Self-Assembly, Megan Twomey

FIU Electronic Theses and Dissertations

Synthetic polymeric materials have gained significant use as biological materials (biomaterials) in biomedical and pharmaceutical applications. As a result, a demand for well-defined polymers with tunable properties has emerged. The synthetic versatility of polymeric biomaterials allows the opportunity to understand the structure-property relationship of materials and their cellular interactions. A novel class of polymeric biomaterials are conjugated polymers (CPs), which possess desirable physicochemical and excellent photophysical properties, including inherent fluorescence. The synthetic versatility of CPs allows easy modification of the conjugated backbone to tune emission and side chain structures to adjust biocompatibility through increased water solubility, controlled biodegradability, and incorporation …


The Influence Of The Proximal Thiolate Ligand And Hydrogen Bond Network Of The Proximal Helix On The Structural And Biochemical Properties Of Chloroperoxidase, Elena Shersher Mar 2016

The Influence Of The Proximal Thiolate Ligand And Hydrogen Bond Network Of The Proximal Helix On The Structural And Biochemical Properties Of Chloroperoxidase, Elena Shersher

FIU Electronic Theses and Dissertations

Chloroperoxidase (CPO) from Caldariomyces fumago is a versatile heme enzyme with great potential for environmental and pharmaceutical applications. It catalyzes a plethora of reactions including halogenation, dismutation, epoxidation, and oxidation. The diverse catalytic capabilities of CPO have long been attributed to the protein’s distinct active site that combines structural features of peroxidases and cytochromes P450. Particularly, the role of the axial thiolate ligand in CPO catalysis has been much debated. Furthermore, no data are available on the role of hydrogen bonding between Arg 26-Asn 37 and Ala 27-Asn 33 of the proximal helix in defining the structural and catalytic properties …


Potential Effects Of Chemical Contamination On South Florida Bonefish Albula Vulpes, Christine P. Beck Jan 2016

Potential Effects Of Chemical Contamination On South Florida Bonefish Albula Vulpes, Christine P. Beck

FIU Electronic Theses and Dissertations

An ecological risk assessment was conducted on the risk to fish of chemical contaminants detected in the habitat of Albula vulpes in South Florida, to evaluate whether contaminants may be a driver of declines in the recreational bonefish fishery. All available contaminant detection data from Biscayne Bay, Florida Bay, and the Florida Keys were compared to federal and state guidelines for aquatic health to identify Contaminants of Potential Ecological Concern (COPECS). For these COPECs, species sensitivity distributions were constructed and compared with recent detections at the 90th centile of exposure. Copper in Biscayne Bay was identified as the highest …