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- Title
- JUVENILE GREEN TURTLE (CHELONIA MYDAS) FORAGING ECOLOGY:FEEDING SELECTIVITY AND FORAGE NUTRIENT ANALYSIS.
- Creator
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Gilbert, Eliza, Ehrhart, Llewellyn, University of Central Florida
- Abstract / Description
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For the endangered green turtle, Chelonia mydas, a fundamental component of recovery and conservation is an understanding of its foraging ecology. Foraging optimality models suggest animals will select resources of high quality over those of low quality. For green turtles, this behavior is important, as sufficient quantities of nutritionally adequate forage items are necessary for growth and reproduction. One intrinsic element in the understanding of green turtle foraging ecology is to...
Show moreFor the endangered green turtle, Chelonia mydas, a fundamental component of recovery and conservation is an understanding of its foraging ecology. Foraging optimality models suggest animals will select resources of high quality over those of low quality. For green turtles, this behavior is important, as sufficient quantities of nutritionally adequate forage items are necessary for growth and reproduction. One intrinsic element in the understanding of green turtle foraging ecology is to identify and document the availability and quality of forage resources preferred by green turtles. The objectives of this study were: 1) determine whether juvenile green turtles showed a feeding preference by comparing prey items in the diet to the availability of those items in the habitat, 2) identify species for which there was selection or avoidance, 3) identify nutritional factors determining selection or avoidance of prey items, and 4) evaluate the nutritional content of the diet. This research was conducted by comparing lavage samples from juvenile green turtles to samples from benthic surveys within the habitat. To determine feeding preference, Ivlev's Electivity Index was used to compare ingested species of algae with those available in the habitat. Nutritional analysis of forage was conducted to identify possible nutrients relating to feeding preference. Juvenile green turtles selectively foraged on Chlorophyta and Rhodophyta. Results indicate that diet selection was based on nutritional content. Both the composite diet and the main diet item, Hypnea spp, had a higher gross energy value, were higher in protein, and lower in fiber than prey items that were avoided. Conservation of green turtles requires effective habitat management, which must be informed by an understanding and evaluation of the habitat. For juvenile green turtles, this study indicates that habitats dominated by Chlorophyta and Rhodophyta may be more important for the health of green turtle populations than habitats dominated by Phaeophyta.
Show less - Date Issued
- 2005
- Identifier
- CFE0000487, ucf:46355
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000487
- Title
- NATIONAL MERIT FINALISTS AT THE UNIVERSITY OF CENTRAL FLORIDA-TRENDS, ATTRITION, AND RETENTION1997-2005.
- Creator
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Norburn, Jill, Tubbs, LeVester, University of Central Florida
- Abstract / Description
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The purpose of this study was to examine the trends, attrition and retention rates of National Merit Finalists at the University of Central Florida between the years of 1997 to 2005. This study was intended to provide information for higher education practitioners, faculty, and administrators to help them better understand the expectations and current trends of National Merit Finalists. The problem was to determine how to increase recruitment and retention while decreasing the attrition rates...
Show moreThe purpose of this study was to examine the trends, attrition and retention rates of National Merit Finalists at the University of Central Florida between the years of 1997 to 2005. This study was intended to provide information for higher education practitioners, faculty, and administrators to help them better understand the expectations and current trends of National Merit Finalists. The problem was to determine how to increase recruitment and retention while decreasing the attrition rates of these highly desirable students. The importance of this study includes identifying trends that may aid in future recruitment efforts for National Merit Finalists; finding the causes of dissatisfaction towards the University among these students; and identifying specific areas in which to alleviate those dissatisfactions. The results will hopefully provide insight into specific recruitment, services, and programming options for these students. The study examined data that was collected from the University of Central Florida's Burnett Honors College database known as FileMaker 8.0. The data examined characteristics such as grade point averages (high school and college); valedictorian and salutatorian status; test scores (SAT and ACT); Honors in the Major (undergraduate thesis) students; Honors and university status (withdrawn, probation, removed, disqualified, enrolled, graduated); Honors college attrition; university attrition; ethnicity; gender ratios; majors; and, prestigious scholarships awarded in college (such as the Rhodes, Truman, Marshall). The actual size of the sample was one hundred ninety-eight National Merit Finalists. Data was also collected from a survey given to all University of Central Florida National Merit Finalists. Descriptive statistics were reported for each of the components examined. This data examined the types of scholarship packages that National Merit Finalists were offered; the reasons students chose the University of Central Florida over other universities; the college recruitment process; hours studied for the PSAT; siblings; perceptions on being a National Merit Finalist; the number of times students changed their majors; job status; transportation; computer attainment; disabilities; and the potential disadvantages of being labeled as a National Merit Finalist. The data could be utilized to examine the trends of our National Merit Finalists, in order to see what is working and what is not in terms or recruitment and retention; and also to further examine what these students want from their institutions. Findings indicated that problems exist in regard to the following: the recruitment of female and minority National Merit Finalists; males historically score higher on the SAT than females; decreasing the attrition rates of this population at the University of Central Florida; the majority of National Merit Finalists at the University of Central Florida come from Florida; the majority of National Merit Finalists at the University of Central Florida do not tend to be high school salutatorians or valedictorians; high school counselors seem to be the least effective tool for recruiting National Merit Finalists at the University of Central Florida; and the majority of National Merit Finalists at the University of Central Florida did not study at all for the PSAT test. However, the University of Central Florida is extremely competitive with other institutions of higher education with regard to scholarship packages. Results also revealed the following: the SAT is a more widely accepted tool for determining NMSC status as opposed to the ACT; the majority of National Merit Finalists have a GPA between 3.600 and 3.999 at the University of Central Florida; the University of Central Florida is succeeding in making its National Merit Finalists feel special during the recruitment process; the most influential reason that National Merit Finalists are choosing UCF is based upon the financial scholarship packages they are offered; and the majority of National Merit Finalists at the University of Central Florida do not feel that there are disadvantages toward being labeled as such. This data provides a basis for further research on National Merit Finalists trends, attrition, and retention. Practical considerations are revealed in the data that will influence future recruitment methods and lead to higher retention rates and increased student satisfaction. Several other recommendations are made to conduct further research studies on the trends, attrition, and retention rates of National Merit Finalists.
Show less - Date Issued
- 2006
- Identifier
- CFE0000931, ucf:46760
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000931
- Title
- IDENTIFICATION OF POTENTIAL LEAD ANTIMALARIAL COMPOUNDS FROM MARINE MICROBIAL EXTRACTS.
- Creator
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Carbonell, Abigail, Chakrabarti, Debopam, University of Central Florida
- Abstract / Description
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Malaria, caused by the parasite Plasmodium falciparum, has a long history as a global health threat. The vector-borne disease causes millions of deaths yearly, especially in developing countries with tropical climates that facilitate transmission. Compounding the problem is the emergence of drug-resistant strains due to overuse of outdated treatments. New compounds with antiplasmodial activity are needed to be developed as effective drugs against malaria. The hypothesis for this project is...
Show moreMalaria, caused by the parasite Plasmodium falciparum, has a long history as a global health threat. The vector-borne disease causes millions of deaths yearly, especially in developing countries with tropical climates that facilitate transmission. Compounding the problem is the emergence of drug-resistant strains due to overuse of outdated treatments. New compounds with antiplasmodial activity are needed to be developed as effective drugs against malaria. The hypothesis for this project is that marine microorganisms have a high likelihood of yielding novel antiplasmodial chemotypes because of their high diversity, which has not yet been explored for antimalarial development. In this project, microbes harvested and fermented by the Harbor Branch Oceanographic Institute in Fort Pierce, Florida were explored as sources for antiplasmodial natural products. Using a SYBR Green I fluorescence-based assay, 1,000 microbial extracts were screened for inhibition of the multidrug-resistant Plasmodium falciparum strain Dd2. Dose-response analysis was performed on 46 fractions from isolates whose extracts demonstrated [greater-than or equal to] 70% inhibition of Dd2 at 1 [micro]g/mL. To evaluate cytotoxicity, the MTS cell viability assay was used to calculate IC50 of extracts from active isolates in NIH/3T3 embryonic mouse fibroblasts. Several extracts demonstrated low IC50 in Dd2 and high IC50 in 3T3, suggesting that they contain potential lead antimalarial compounds. Extracts with high selectivity indices (potent plasmodial inhibition with low mammalian toxicity) have been prioritized for dereplication, with the goal of identifying novel active components that can be developed as antimalarial drugs.
Show less - Date Issued
- 2013
- Identifier
- CFH0004332, ucf:45035
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004332
- Title
- Reproductive life history and signal evolution in a multi-species assemblage of electric fish.
- Creator
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Waddell, Joseph, Crampton, William, Fedorka, Kenneth, Quintana-Ascencio, Pedro, Stoddard, Philip, University of Central Florida
- Abstract / Description
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Animals that co-occur in sympatry with multiple closely-related species use reproductive mate attraction signals not only to assess the quality of a potential conspecific mate (sexual selection), but also to discriminate conspecifics from heterospecifics (species recognition). However, the extent to which sexual selection and species recognition may interact, or even conflict, is poorly known. Neotropical electric fish offer unrivaled opportunities for understanding this problem. They...
Show moreAnimals that co-occur in sympatry with multiple closely-related species use reproductive mate attraction signals not only to assess the quality of a potential conspecific mate (sexual selection), but also to discriminate conspecifics from heterospecifics (species recognition). However, the extent to which sexual selection and species recognition may interact, or even conflict, is poorly known. Neotropical electric fish offer unrivaled opportunities for understanding this problem. They generate simple, stereotyped mate attraction signals that are easy to record and quantify, and that are well-understood from the neurobiological perspective. Additionally, they live in electrically-crowded environments, where multiple congeners live and reproduce in close proximity. This dissertation reports an investigation of electric signal diversity and reproductive life history in a nine-species assemblage of the electric fish genus Brachyhypopomus from the upper Amazon. A year-long quantitative sampling program yielded a library of electric signal recordings from (>)3,000 individuals and an accompanying collection of preserved specimens from which suites of informative life history traits were measured. These data were used to understand basic reproductive biology, and to describe sexually dimorphic and interspecific diversity in electric signals. By integrating approaches from ecology, physiology, and evolutionary biology, novel perspectives are provided on: 1. how sexual selection and species recognition interact to shape signal diversity and the occupation of signal space in multi-species animal communities; 2. how extreme seasonal variation in Amazonian ecosystems influences trade-offs in the allocation of reproductive resources (-) including mate attraction signals, and; 3. how environmental variation shapes general life-history traits in a diverse tropical animal assemblage.
Show less - Date Issued
- 2017
- Identifier
- CFE0006925, ucf:51689
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006925