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Full-Text Articles in Biology

Effect Of Stress On Mucin Expression In The Gastrointestinal Tract Of Mice., Bupe Martha Habiyambere Dec 2010

Effect Of Stress On Mucin Expression In The Gastrointestinal Tract Of Mice., Bupe Martha Habiyambere

Electronic Theses and Dissertations

This study investigated the effects of chronic stress on mucin expression in the GIT of mice. Sixteen ICR male mice were randomly divided into treated and control animals. Restraint stress was applied to the treated group for 21 days. Body weight (BW) changes and feed consumed (FC) were regularly recorded. After 21 days mice were euthanized and blood, GIT mucosa, and GIT sections were collected. Serum corticosterone levels were determined. The GIT sections were fixed, paraffin embedded, sectioned, and stained with AB-PAS to visualize goblet cells. Mucin expression was determined using qPCR. As expected stressed mice showed higher corticosterone than …


Role Of Eukaryotic Sel-1 Like Repeat Containing Genes In Helicobacter Pylori Evolution And Pathogenesis., Kalyani Putty Dec 2010

Role Of Eukaryotic Sel-1 Like Repeat Containing Genes In Helicobacter Pylori Evolution And Pathogenesis., Kalyani Putty

Electronic Theses and Dissertations

Background: Helicobacter pylori (Hp) establishes life-long gastric infection in billions of humans, and is often responsible for diseases such as peptic ulcer and gastric cancer. Cumulative actions of genetic drift and natural selection over several millennia sculpted the present Hp population structure, which is characterized by extreme genetic diversity and striking geographic clustering of genotypes. Natural selection is more commonly imprinted in DNA sequences of Hp proteins that interact with host components; however, in most instances biological relevance of selection during Hp infection remains unknown. Here, I attempted to elucidate the consequence of natural selection in two different contexts: (1) …


The Effects Of Betadine®, Polyvinylpyrrolidone (Pvp), And Iodine On Regeneration In The Planarian Dugesia Tigrina., Traci R. Shaffer May 2010

The Effects Of Betadine®, Polyvinylpyrrolidone (Pvp), And Iodine On Regeneration In The Planarian Dugesia Tigrina., Traci R. Shaffer

Electronic Theses and Dissertations

The freshwater planarian has a great capacity to regenerate and is an ideal animal model in the study of stem cell and regeneration biology. In this study planarian regenerating new tails were exposed to nonlethal doses of Betadine®, Polyvinylpyrrolidone (PVP), and Iodine. Betadine® is a topical antiseptic commonly used in the healthcare setting and may have a detrimental effect on wound healing. PVP is linked to iodine to create povidone-iodine, the active ingredient in Betadine®. Initially, a preliminary test was performed on the worms to determine the nonlethal concentrations of these chemicals . After this nonlethal concentration was determined, tails …


Characterizing The Vertical Structure And Structural Diversity Of Florida Oak Scrub Vegetation Using Discrete-Return Lidar, James J. Angelo Jan 2010

Characterizing The Vertical Structure And Structural Diversity Of Florida Oak Scrub Vegetation Using Discrete-Return Lidar, James J. Angelo

Electronic Theses and Dissertations

Vertical structure, the top-to-bottom arrangement of aboveground vegetation, is an important component of forest and shrubland ecosystems. For many decades, ecologists have used foliage height profiles and other measures of vertical structure to identify discrete stages in post-disturbance succession and to quantify the heterogeneity of vegetation. Such studies have, however, required resource-intensive field surveys and have been limited to relatively small spatial extents (e.g.,


Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether Jan 2010

Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether

Electronic Theses and Dissertations

Understanding the nature of genetic variation in natural populations is an underlying theme of population genetics. In recent years population genetics has benefited from the incorporation of landscape and environmental data into pre-existing models of isolation by distance (IBD) to elucidate features influencing spatial genetic variation. Many of these landscape genetics studies have focused on populations separated by discrete barriers (e.g., mountain ridges) or species with specific habitat requirements (i.e., habitat specialists). One difficulty in using a landscape genetics approach for taxa with less stringent habitat requirements (i.e., generalists) is the lack of obvious barriers to gene flow and preference …


The Role Of The Feral Pig (Sus Scrofa) As A Disturbance Agent And Seed Disperser In Central Florida's Natural Lands, Camille Rose Brescacin Jan 2010

The Role Of The Feral Pig (Sus Scrofa) As A Disturbance Agent And Seed Disperser In Central Florida's Natural Lands, Camille Rose Brescacin

Electronic Theses and Dissertations

Feral pigs (Sus scrofa) are considered to be among the world’s worst invasive species due to their successful invasion and ecological and economic impact to native and agricultural plants and animals around the world. Feral pigs are significant disturbance agents that destroy plant communities, change soil characteristics, alter nutrient cycling, and create open sites for colonization of both native and non-native plant species through their foraging behavior called rooting. In contrast to native animal disturbances, rooting is a striking feature in the landscape that varies in space, seasonal timing, frequency (number of times rooted), and intensity (depth of rooting). During …


Estimating Diet And Food Selectivity Of The Lower Keys Marsh Rabbit Using Stable Isotope Analysis, Matthew James Gordon Jan 2010

Estimating Diet And Food Selectivity Of The Lower Keys Marsh Rabbit Using Stable Isotope Analysis, Matthew James Gordon

Electronic Theses and Dissertations

Understanding the effect of food abundance on feeding behavior can benefit conservation efforts in many ways, such as to determine whether impacted environments need food supplementation, whether different locations of threatened species contain different food abundances, or whether reintroduction sites are missing key components of a species’ diet. I studied the relationship between feeding behavior and food abundance in the Lower Keys marsh rabbit (Sylvilagus palustris hefneri), an endangered subspecies endemic to the lower Florida Keys. Specifically, my study set out to measure the relative abundance of the primary plants within the natural habitat of the Lower Keys marsh rabbit …


The Influence Of Sexual Selection On Behavioral And Physiological Mechanisms Underlying Reproductive Success In Male Cape Ground Squirrels (Xerus Inauris), Mary Beth Manjerovic Jan 2010

The Influence Of Sexual Selection On Behavioral And Physiological Mechanisms Underlying Reproductive Success In Male Cape Ground Squirrels (Xerus Inauris), Mary Beth Manjerovic

Electronic Theses and Dissertations

Sexual selection is considered a powerful evolutionary force responsible for the enormous diversity found in reproductive morphology, physiology, and behavior. I addressed questions related to selection in the Cape ground squirrel (Xerus inauris), a species characterized as highly social and promiscuous. These attributes often are responsible for variance in male reproductive success and as such, sexual selection theory predicts increased opportunity for sexual selection. I confirm that the predominant mechanism underlying genital evolution and competition for paternity in X. inauris is sperm competition. I find evidence that investment in sperm competition is costly and may reflect immunocompetence. I quantify reproductive …


Treefrog (Hyla Squirella) Responses To Rangeland And Management In Semi-Tropical Florida, Usa, Kathryn Windes Jan 2010

Treefrog (Hyla Squirella) Responses To Rangeland And Management In Semi-Tropical Florida, Usa, Kathryn Windes

Electronic Theses and Dissertations

As urban areas expand, agricultural lands become increasingly important habitat for many species. Compared to some types of agricultural land-use, ranchlands provide vast expanses of minimally modified habitat that support many threatened and endangered species. Conservation biologists can promote ecologically sound management approaches by quantifying the effects of agricultural practices on resident species. I examined the effects of pasture management, cattle grazing, and landscape characteristics on both adult and larval treefrogs in a ranchland in south-central Florida. I experimentally determined optimal deployment of artificial treefrog shelters constructed of polyvinylchloride (PVC) pipe to efficiently sample adult treefrogs (Chapter 1). Seventy-two shelters …


Abiotic Differences Between Green Turtle (Chelonia Mydas) Nests In Natural Beach And Engineered Dunes: Effects On Hatching Success, Martha Balfour Jan 2010

Abiotic Differences Between Green Turtle (Chelonia Mydas) Nests In Natural Beach And Engineered Dunes: Effects On Hatching Success, Martha Balfour

Electronic Theses and Dissertations

Habitat loss is among the biggest threats to conservation worldwide, so habitat restoration plays an increasing role in endangered species management. This is especially true for species with high site fidelity, such as nesting marine turtles. Sand replenishment is commonly used to restore coastal beaches after severe erosion events, and may affect marine turtles and other species that live or reproduce in that habitat. I investigated how abiotic characteristics of sand used in a dune restoration project at Archie Carr National Wildlife Refuge, Florida, affected reproduction of the federally-endangered green turtle (Chelonia mydas). Sand structure and composition can affect egg …


An Assessment Of Sea Turtle Nesting Behavior In Relation To Hurricane- And Restoration-Induced Beach Morphodynamics, Tonya Michele Long Jan 2010

An Assessment Of Sea Turtle Nesting Behavior In Relation To Hurricane- And Restoration-Induced Beach Morphodynamics, Tonya Michele Long

Electronic Theses and Dissertations

Coastal habitats are highly dynamic and vulnerable to landscape-level disturbances such as storms and restoration projects. Along the east coast of Florida these areas are particularly valuable as they provide significant nesting habitat for two sea turtle species, the threatened loggerhead (Caretta caretta) and the endangered green turtle (Chelonia mydas). This coast was heavily impacted by three major hurricanes in 2004 and in some areas by large restoration projects in 2005. Recent remote sensing methods allow for broad evaluation of the shoreline and thus the ability to assess sea turtle nesting habitat at a landscape scale. I collected nesting data …


Neuronal Calcium Regulation And Cellular Stress In A Malignant Hyperthermia Disease Model, Jason Santiago Jan 2010

Neuronal Calcium Regulation And Cellular Stress In A Malignant Hyperthermia Disease Model, Jason Santiago

Electronic Theses and Dissertations

Calcium ions (Ca2+) are essential signaling molecules and must be carefully regulated to preserve specificity in function. One indispensible Ca2+ signaling protein is the ryanodine receptor (RyR) calcium release channel. RyR1 is essential for muscle contraction, and RyR1mutations can lead to severe muscle disorders such as malignant hyperthermia (MH). Recently, a mouse model of human MH (Y522S-RyR1) has been developed. In skeletal muscle, Y522S-RyR1 exhibits an increased sensitivity to activation resulting in Ca2+ leak, mitochondrial disorganization, and cellular stress. Although RyR1 expression is limited in the brain, the cerebellum may be particularly vulnerable to this disease because RyR1 is highly …


Investigating Instructors' Conceptions Of Evolution Through The Development Of The Classroom Test Of Evolutionary Reasoning, Patricia Eileen Palko Jan 2010

Investigating Instructors' Conceptions Of Evolution Through The Development Of The Classroom Test Of Evolutionary Reasoning, Patricia Eileen Palko

Electronic Theses and Dissertations

In order to assess the evolutionary understanding of high school biology teachers, an instrument entitled the Classroom Test of Evolutionary Reasoning (CTER) was developed. Content, response process, relations to another variable (the Conceptual Inventory of Natural Selection, or CINS), and internal structure evidence were compiled. The second version of the CTER was found to have adequate reliability and validity estimates to allow it to continue to be used as a measurement tool for an understanding of evolution. When assessing a sample of teachers (n = 724), the mean score was 6.35 out of a possible 13 points. The sample was …


The Fungal Connection: Characterizing The Ectomycorrhizal Community And Belowground Response To Restoration Treatments In Northern Mississippi., Ashley Jane Craig Jan 2010

The Fungal Connection: Characterizing The Ectomycorrhizal Community And Belowground Response To Restoration Treatments In Northern Mississippi., Ashley Jane Craig

Electronic Theses and Dissertations

Ectomycorrhizal (ECM) fungi are symbionts on the roots of woody plant species throughout the world. These fungi provide plants with nutrients and are important drivers of ecosystem processes. ECM fungi vary in their effect on host plants and host-specificity, making them important considerations in restoration projects seeking to restore target tree species. Restoration strategies such as burning and thinning may have strong impacts on ECM fungi, and given the that ECM are important in structuring aboveground communities and maintaining certain dominant plant taxa, knowledge of ECM fungal response is needed to ensure restoration efforts succeed. Using molecular methods, this research …


The Effects Of Ecological Restoration On Soil Microbial Enzyme Activities And Leaf Litter Decomposition, Anthony Jason Rietl Jan 2010

The Effects Of Ecological Restoration On Soil Microbial Enzyme Activities And Leaf Litter Decomposition, Anthony Jason Rietl

Electronic Theses and Dissertations

This study examined the immediate effects of ecological restoration on soil enzyme activities and decomposition. The activities of five enzymes: phosphatase, ?-glucosidase, ?-N-acetylglucosadminidase (NAGase), phenol oxidase, and lignin-peroxidase were measured in both soils and on decomposing Quercus falcata leaf litter in unburned, burned, and burned and thinned plots in a mesic forest in northern Mississippi. Rates of decomposition were also assessed for Q. falcata leaf litter at each plot. The restoration treatments decreased phosphatase activity in relation to an increase in soil organic matter after the fire, and increased NAGase activity in relation to a decrease in leaf litter after …


Development Of Ultra-Sensitive Fluorescence Photoamplification Assays For The Detection Of Molecular Recognition Events, Tiffany Priscilla Gustafson Jan 2010

Development Of Ultra-Sensitive Fluorescence Photoamplification Assays For The Detection Of Molecular Recognition Events, Tiffany Priscilla Gustafson

Electronic Theses and Dissertations

During the course of this research a novel method which couples the molecular recognition-triggered photoamplification chain in diaryl ketone adducts of dithiane with a "turn-off" or "turn-on" fluorescence-based assay for the detection of biological targets and ligands, regardless of their nature, through a molecular recognition event has been developed. This research has included several key steps, the most significant being: (1) the design of fluorophore adducts or dyads which recover fluorescence upon photocleavage for a "turn-on" assay and the identification of fluorophores which are quenched upon the photochemical release of a quencher for a "turn off" assay; (2) Optimization of …


Taxonomy Versus Phylogeny Phylogeography Of Marsh Rabbits Without Hopping To Conclusions, Rosanna M. Tursi Jan 2010

Taxonomy Versus Phylogeny Phylogeography Of Marsh Rabbits Without Hopping To Conclusions, Rosanna M. Tursi

Electronic Theses and Dissertations

Subspecific taxonomic designations solely based on morphological characters can often lead to erroneous assumptions about the evolutionary history of populations. This study sought to investigate evolutionary questions and conservation implications associated with morphological subspecific designations of island populations. To this end, I focused my attention on the Lower Keys of Florida, a unique chain of islands with well-known geologic history and rich in endemic, endangered subspecies. I employed genetic analyses to evaluate historical variation and contemporary restriction of gene flow between the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) and its sister mainland taxa. A Bayesian phylogeny using 1063 …


Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra Jan 2010

Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra

Electronic Theses and Dissertations

The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively). …


Geographic Variation In Post-Mating Immune Gene Expression In Drosophila Melanogaster, Cheryl Ann Pinzone Jan 2010

Geographic Variation In Post-Mating Immune Gene Expression In Drosophila Melanogaster, Cheryl Ann Pinzone

Electronic Theses and Dissertations

An organism's immune response may vary due to pathogen pressure in its environment, as well as due to interactions with other organisms. These factors, along with geographic rules (i.e. Gloger's rule) may influence the geographic distribution of the immune response within populations of a species. Here we use real-time quantitative PCR to measure the immune gene expression in six populations collected along the eastern U.S. of Drosophila melanogaster after mating. Antimicrobial genes did not show significant differences in expression due to location, whereas we did observe differences in anti-fungal and pro-phenoloxidase (anti-macromolecule) related genes. These differences in anti-macromolecule resistance are …


Clonality And Genetic Diversity In Polygonella Myriophylla, A Lake Wales Ridge Endemic Plant, Genevieve Metzger Jan 2010

Clonality And Genetic Diversity In Polygonella Myriophylla, A Lake Wales Ridge Endemic Plant, Genevieve Metzger

Electronic Theses and Dissertations

Although capable of sexual reproduction, many plants also rely heavily on clonal reproduction. The formation of multiple, physiologically-independent units with the same genotype has important implications for spatial genetic structure and genetic diversity in these plants. The endangered scrub-dwelling perennial, Polygonella myriophylla is known to reproduce both sexually and clonally but no study to date has been able to investigate the spatial genetic patterns that occur in this species. I use microsatellite markers to investigate questions about clonal structure and genetic diversity in five populations of P. myriophylla and address some of the implications of my findings for conservation of …


Biogeography And Diversification In The Neotropics: Testing Macroevolutionary Hypotheses Using Molecular Phylogenetic Data, Juan Manuel Daza Rojas Jan 2010

Biogeography And Diversification In The Neotropics: Testing Macroevolutionary Hypotheses Using Molecular Phylogenetic Data, Juan Manuel Daza Rojas

Electronic Theses and Dissertations

Lineage diversification in the Neotropics is an interesting topic in evolutionary biology and one of the least understood. The complexity of the region precludes generalizations regarding the historical and evolutionary processes responsible for the observed high diversity. Here, I use molecular data to infer evolutionary relationships and test hypotheses of current taxonomy, species boundaries, speciation and biogeographic history in several lineages of Neotropical snakes. I comprehensively sampled a widely distributed Neotropical colubrid snake and Middle American pitvipers and combined my data with published sequences. Within the colubrid genus Leptodeira, mitochondrial and nuclear markers revealed a phylogeograhic structure that disagrees with …