Current Search: evolution (x)
Pages
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Title
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The part played by labour in the transition from ape to man.
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Date Issued
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1949
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Identifier
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2707490, CFDT2707490, ucf:5163
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/FCLA/DT/2707490
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Title
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DEFENSE TRADE-OFFS IN THE EVOLUTION OF THE FRUITS AND FLOWERS OF GENUS CORNUS.
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Creator
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De La Pascua, Danielle R, Mason, Chase, University of Central Florida
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Abstract / Description
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The optimal defense hypothesis predicts that the allocation of plant defenses across plant organs is proportional to the importance of a given organ to plant fitness. Despite this, much less work has been devoted to the study of reproductive defenses in plants relative to vegetative structures like leaves. This study examines the apparancy hypothesis and the resource availability hypothesis using a phylogenetic comparative approach within the genus Cornus. During the 2016 growing season,...
Show moreThe optimal defense hypothesis predicts that the allocation of plant defenses across plant organs is proportional to the importance of a given organ to plant fitness. Despite this, much less work has been devoted to the study of reproductive defenses in plants relative to vegetative structures like leaves. This study examines the apparancy hypothesis and the resource availability hypothesis using a phylogenetic comparative approach within the genus Cornus. During the 2016 growing season, plants of 25 species of Cornus were tracked for flower and fruit phenology as well as sampled for floral and fruit tissue in a common garden experiment at the Arnold Arboretum of Harvard University. This tissue was used to quantify floral and fruit defensive chemistry (e.g. tannin activity, total phenolics, total flavonoids, titratable acidity), and fruit palatability traits (e.g. water, sugar, lipid, and protein content), and the color of reproductive structure using reflectance spectroscopy. Native habitat environmental data was obtained using digitized herbarium records and publicly available environmental data layers. Trait-trait and trait-environment relationships were assessed with phylogenetic generalized least squares regression. The evolution of later flowering phenology was correlated with increased floral phenolics and tannins, and the evolution of increased fruiting duration was correlated with increased fruit tannins, both supporting the apparancy hypothesis. Additionally, the evolution of higher fruit sugar content was correlated with higher fruit tannins, and a strong evolutionary trade-off between the production of tannins and the production of flavonoids was observed. With respect to habitat, floral and fruit flavonoids and tannins were consistently lower in species native to warmer environments, while fruit phenolics and was higher in drier environments, which may support the resource availability hypothesis.
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Date Issued
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2019
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Identifier
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CFH2000508, ucf:45674
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH2000508
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Title
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A Study of Central Florida College Students' Acceptance of the Theory of Evolution, Microevolution, Macroevolution, and Human Evolution.
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Creator
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Schleith, David, Murray, Kenneth, Baldwin, Lee, Doherty, Walter, Everett, Robert, University of Central Florida
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Abstract / Description
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In order to study the teaching and learning of the theory of evolution and determine levels of acceptance of the theory of evolution among college students studying biology in Central Florida, the Inventory of Student Evolution Acceptance, I-SEA, was administered to over 500 university students enrolled in a biology course during the Fall 2016 term. An analysis of 489 completed surveys demonstrated strong overall acceptance of the theory of evolution (average score = 103 out of 120 total...
Show moreIn order to study the teaching and learning of the theory of evolution and determine levels of acceptance of the theory of evolution among college students studying biology in Central Florida, the Inventory of Student Evolution Acceptance, I-SEA, was administered to over 500 university students enrolled in a biology course during the Fall 2016 term. An analysis of 489 completed surveys demonstrated strong overall acceptance of the theory of evolution (average score = 103 out of 120 total possible). Of all students, 78% fell into the category of very high acceptance of the theory of evolution. Students who reported attending worship services weekly or more scored statistically significantly lower on the I-SEA than students who reported attending worship services less than weekly. The level of previous high school coursework in biology(-)whether honors, or advanced biology courses were taken-- did not translate into statistically significant differences in acceptance of evolution as measured by the I-SEA. Three subscales contained within the Inventory of Student Evolution Acceptance are designed to measure student acceptance of microevolution, macroevolution, and human evolution. Students demonstrate higher levels of acceptance of microevolution than macroevolution or human evolution. These findings serve to inform educational leaders and science educators regarding students' worldview and how worldview may inform what students accept as true and valid. The I-SEA serves as a useful educational tool to inform instructional decisions in the biology classroom.
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Date Issued
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2017
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Identifier
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CFE0006792, ucf:51818
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006792
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Title
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Biology and war.
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Creator
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Thomson, J. Arthur (John Arthur)
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Date Issued
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1915
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Identifier
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331856, CFDT331856, ucf:5170
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/FCLA/DT/331856
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Title
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MODELING AND PARTITIONING THE NUCLEOTIDE EVOLUTIONARY PROCESS FOR PHYLOGENETIC AND COMPARATIVE GENOMIC INFERENCE.
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Creator
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Castoe, Todd, Parkinson, Christopher, University of Central Florida
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Abstract / Description
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The transformation of genomic data into functionally relevant information about the composition of biological systems hinges critically on the field of computational genome biology, at the core of which lies comparative genomics. The aim of comparative genomics is to extract meaningful functional information from the differences and similarities observed across genomes of different organisms. We develop and test a novel framework for applying complex models of nucleotide evolution to solve...
Show moreThe transformation of genomic data into functionally relevant information about the composition of biological systems hinges critically on the field of computational genome biology, at the core of which lies comparative genomics. The aim of comparative genomics is to extract meaningful functional information from the differences and similarities observed across genomes of different organisms. We develop and test a novel framework for applying complex models of nucleotide evolution to solve phylogenetic and comparative genomic problems, and demonstrate that these techniques are crucial for accurate comparative evolutionary inferences. Additionally, we conduct an exploratory study using vertebrate mitochondrial genomes as a model to identify the reciprocal influences that genome structure, nucleotide evolution, and multi-level molecular function may have on one another. Collectively this work represents a significant and novel contribution to accurately modeling and characterizing patterns of nucleotide evolution, a contribution that enables the enhanced detection of patterns of genealogical relationships, selection, and function in comparative genomic datasets. Our work with entire mitochondrial genomes highlights a coordinated evolutionary shift that simultaneously altered genome architecture, replication, nucleotide evolution and molecular function (of proteins, RNAs, and the genome itself). Current research in computational biology, including the advances included in this dissertation, continue to close the gap that impedes the transformation of genomic data into powerful tools for the analysis and understanding of biological systems function.
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Date Issued
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2007
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Identifier
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CFE0001548, ucf:47138
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0001548
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Title
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POLYMER-DERIVED SI-AL-C-N CERAMICS:OXIDATION, HOT-CORROSION, AND STRUCTURAL EVOLUTION.
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Creator
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Wang, Yiguang, An, Linan, University of Central Florida
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Abstract / Description
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Polymer-derived ceramics are a new class of materials synthesized by thermal decomposition of polymer precursors. Previous studies have shown that the materials exhibit excellent thermo-mechanical properties and can be stable at temperatures up to 2000oC. Furthermore, the novel polymer-to-ceramics process enables the manipulation of the ceramic structures at the atomic/nano level by designing the chemistry of polymer precursors and controlling the pyrolysis conditions, thereby, the properties...
Show morePolymer-derived ceramics are a new class of materials synthesized by thermal decomposition of polymer precursors. Previous studies have shown that the materials exhibit excellent thermo-mechanical properties and can be stable at temperatures up to 2000oC. Furthermore, the novel polymer-to-ceramics process enables the manipulation of the ceramic structures at the atomic/nano level by designing the chemistry of polymer precursors and controlling the pyrolysis conditions, thereby, the properties of ceramics. In this dissertation, oxidation/hot-corrosion behavior and the structural evolution of Si-Al-C-N ceramics have been studied. The structural evolution and crystallization behavior of the SiCN and SiAlCN ceramics are investigated using FT-IR, XRD, and NMR. The results revealed that aluminum could greatly affect the structural evolution and crystallization behavior of polymer-derived ceramics, resulting to better stability. The oxidation kinetics of the SiCN and SiAlCN ceramics in air is determined by directly measuring the thickness of the oxide scale with SEM as a function of oxidation time. The results revealed that while the oxidation of the SiCN ceramics follows parabolic kinetics in all of the ranges of testing temperatures, oxidation of the SiAlCN ceramics is complicated: their oxidation rates are similar to that of SiCN ceramics at the earlier stage, but they decrease to very low levels after a certain time. The oxidation rate of the SiAlCN ceramics is more than an order of magnitude lower than any other silicon based ceramics previously reported. The transportation behavior of oxygen through the oxide scales is studied by 18O diffusion. The results indicate that oxidation is controlled by molecular oxygen diffusing through the oxides for both SiCN and SiAlCN ceramics; however, the oxygen diffusion rate in the oxides on SiAlCN ceramics is remarkably retarded. The structures of the oxides are characterized by XRD and NMR. A structural model is advanced to account for the aluminum effect on the oxygen diffusion in the oxide. The oxidation and hot-corrosion kinetics of the SiCN and SiAlCN ceramics in water vapor are determined by measuring their weight changes as a function of annealing time. The kinetic constants, kp and kl, are obtained by fitting the weight-change data with a paralinear model. The results reveal that the SiAlCN ceramics have a much better corrosion resistance than the SiCN and CVD SiC/Si3N4. After annealing at 1400oC for 300 hours, the SiAlCN-20 still retains more than 70% of its original strength, while the SiCN only retains about 20% of its original strength. The improvement in oxidation/hot-corrosion resistance of the SiAlCN ceramics is attributed to the low activity of the SiO2 in the Al2O3-containing silica. In summary, I have developed a new class of high-temperature materials, Si-Al-C-N ceramics. It is demonstrated that these new materials have excellent oxidation and corrosion resistance and thermal stability. Together with their easy processability, the materials will find many high temperature applications such as environmental barrier coatings, ceramic matrix composites, and MEMS for harsh environments.
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Date Issued
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2006
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Identifier
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CFE0001017, ucf:46810
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0001017
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Title
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MUSIC AND PALEOLITHIC MAN: THE SOUNDTRACK OF HUMAN COGNITIVE DEVELOPMENT.
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Creator
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Angel, Samantha, Walker, John, University of Central Florida
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Abstract / Description
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Archaeologists have pored over countless texts of the ancient civilizations, attempting to piece together bygone worlds. However, relatively little work has been done to reconstruct the musical history of these societies, and even less on why their musical histories are important. This paper aims at a synthesis between the ancient Egyptian and classical Greek archaeological records to analyze the importance of music in Paleolithic human cognitive development. Countless musical instruments...
Show moreArchaeologists have pored over countless texts of the ancient civilizations, attempting to piece together bygone worlds. However, relatively little work has been done to reconstruct the musical history of these societies, and even less on why their musical histories are important. This paper aims at a synthesis between the ancient Egyptian and classical Greek archaeological records to analyze the importance of music in Paleolithic human cognitive development. Countless musical instruments have been discovered globally, ranging from pre-Columbian bone flutes in Oaxaca, Mexico to ancient trumpets in Egyptian burials (Barber et al 2009). Apart from their place in a museum, minimal work has been done to ascertain their importance to human society as a whole. This thesis attempts to display the crucial need for more research in this field. The recent decline in support for arts education in favor of 'hard sciences' and mathematics is deeply disturbing; the history of humanity should be important not only to anthropologists and historians, but to members of all disciplines. This lack of interest in 'soft sciences' and the arts may lead to a complete loss of ancient musical history; a loss that would be devastating to history, anthropology and the worlds. The contents of this paper portray both the ancient importance of music, and how it contributed to increased cognitive faculties during hominid development.
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Date Issued
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2012
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Identifier
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CFH0004182, ucf:44853
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH0004182
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Title
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BIOGEOGRAPHY AND DIVERSIFICATION IN THE NEOTROPICS: TESTING MACROEVOLUTIONARY HYPOTHESES USING MOLECULAR PHYLOGENETIC DATA.
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Creator
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Daza Rojas, Juan Manuel, Parkinson, Christopher, University of Central Florida
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Abstract / Description
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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...
Show moreLineage 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 the taxonomy based only on morphology. Instead, the phylogenetic structure corresponds to specific biogeographic regions within the Neotropics. Molecular evidence combined with explicit divergence time estimates reject the hypothesis that highland pitvipers in Middle America originated during the climatic changes during the Pleistocene. My data, instead, shows that pitviper diversification occurred mainly during the Miocene, a period of active orogenic activity. Using multiple lineages of Neotropical snakes in a single phylogenetic tree, I describe how the closure of the Isthmus of Panama generated several episodes of diversification as opposed to the Motagua-Polochic fault in Guatemala where a single vicariant event may have led to diversification of snakes with different ecological requirements. This finding has implications for future biogeographic studies in the region as explicit temporal information can be readily incorporated in molecular clock analyses. Bridging the gap between the traditional goals of historical biogeography (i.e., area relationships) with robust statistical methods, my research can be applied to multiple levels of the biological hierarchy (i.e., above species level), other regional systems and other sub-disciplines in biology such as medical research, evolutionary ecology, taxonomy and conservation.
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Date Issued
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2010
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Identifier
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CFE0003101, ucf:48328
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003101
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Title
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Character Evolution and Microbial Community Structure in a Host-associated Grasshopper.
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Creator
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Raszick, Tyler, Song, Hojun, Fedorka, Kenneth, Hoffman, Eric, University of Central Florida
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Abstract / Description
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The spotted bird grasshopper, Schistocerca lineata Scudder (Orthoptera: Acrididae), is a widely distributed species found throughout most of the continental United States and southern Canada. This species is known to be highly variable in morphology, with many distinct ecotypes across its native range. These ecotypes display high levels of association with type-specific host plants. Understanding the evolutionary relationships among different ecotypes is crucial groundwork for studying the...
Show moreThe spotted bird grasshopper, Schistocerca lineata Scudder (Orthoptera: Acrididae), is a widely distributed species found throughout most of the continental United States and southern Canada. This species is known to be highly variable in morphology, with many distinct ecotypes across its native range. These ecotypes display high levels of association with type-specific host plants. Understanding the evolutionary relationships among different ecotypes is crucial groundwork for studying the process of ecological differentiation. I examine four ecotypes from morphological and phylogeographic perspectives, and look for evidence of distinct evolutionary lineages within the species. I also begin to explore the potential role of the microbial community of these grasshoppers in ecological divergence by using 454 pyrosequencing to see if the microbial community structure reflects the ecology of the grasshoppers. I find support for a distinct aposematic lineage when approaching the data from a phylogeographic perspective and also find that this ecotype tends to harbor a unique bacterial community, different from that of a single other ecotype.
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Date Issued
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2014
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Identifier
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CFE0005540, ucf:50316
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005540
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Title
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Evolution Through the Search for Novelty.
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Creator
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Lehman, Joel, Stanley, Kenneth, Gonzalez, Avelino, Wiegand, Rudolf, Hoffman, Eric, University of Central Florida
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Abstract / Description
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I present a new approach to evolutionary search called novelty search, wherein only behavioral novelty is rewarded, thereby abstracting evolution as a search for novel forms. This new approach contrasts with the traditional approach of rewarding progress towards the objective through an objective function. Although they are designed to light a path to the objective, objective functions can instead deceive search into converging to dead ends called local optima.As a significant problem in...
Show moreI present a new approach to evolutionary search called novelty search, wherein only behavioral novelty is rewarded, thereby abstracting evolution as a search for novel forms. This new approach contrasts with the traditional approach of rewarding progress towards the objective through an objective function. Although they are designed to light a path to the objective, objective functions can instead deceive search into converging to dead ends called local optima.As a significant problem in evolutionary computation, deception has inspired many techniques designed to mitigate it. However, nearly all such methods are still ultimately susceptible to deceptive local optima because they still measure progress with respect to the objective, which this dissertation will show is often a broken compass. Furthermore, although novelty search completely abandons the objective, it counterintuitively often outperforms methods that search directly for the objective in deceptive tasks and can induce evolutionary dynamics closer in spirit to natural evolution. The main contributions are to (1) introduce novelty search, an example of an effective search method that is not guided by actively measuring or encouraging objective progress; (2) validate novelty search by applying it to biped locomotion; (3) demonstrate novelty search's benefits for evolvability (i.e. the abilityof an organism to further evolve) in a variety of domains; (4) introduce an extension of novelty search called minimal criteria novelty search that brings a new abstraction of natural evolution to evolutionary computation (i.e. evolution as a search for many ways of meeting the minimal criteria of life); (5) present a second extension of novelty search called novelty search with local competition that abstracts evolution instead as a process driven towards diversity with competition playing a subservient role; and (6) evolve a diversity of functional virtual creatures in a single run as a culminating application of novelty search with local competition. Overall these contributions establish novelty search as an important new research direction for the field of evolutionary computation.
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Date Issued
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2012
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Identifier
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CFE0004398, ucf:49390
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0004398
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Title
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PHASE-FIELD SIMULATION OF MICROSTRUCTURALDEVELOPMENT INDUCED BY INTERDIFFUSIONFLUXES UNDER MULTIPLE GRADIENTS.
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Creator
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Mohanty, Rashmi, Sohn, Yongho, University of Central Florida
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Abstract / Description
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The diffuse-interface phase-field model is a powerful method to simulate and predict mesoscale microstructure evolution in materials using fundamental properties of thermodynamics and kinetics. The objective of this dissertation is to develop phase-field model for simulation and prediction of interdiffusion behavior and evolution of microstructure in multi-phase binary and ternary systems under composition and/or temperature gradients. Simulations were carried out with emphasis on...
Show moreThe diffuse-interface phase-field model is a powerful method to simulate and predict mesoscale microstructure evolution in materials using fundamental properties of thermodynamics and kinetics. The objective of this dissertation is to develop phase-field model for simulation and prediction of interdiffusion behavior and evolution of microstructure in multi-phase binary and ternary systems under composition and/or temperature gradients. Simulations were carried out with emphasis on multicomponent diffusional interactions in single-phase system, and microstructure evolution in multiphase systems using thermodynamics and kinetics of real systems such as Ni-Al and Ni-Cr-Al. In addition, selected experimental studies were carried out to examine interdiffusion and microstructure evolution in Ni-Cr-Al and Fe-Ni-Al alloys at 1000C. Based on Onsager's formalism, a phase-field model was developed for the first time to simulate the diffusion process under an applied temperature gradient (i.e., thermotransport) in single- and two-phase binary alloys. Development of concentration profiles with uphill diffusion and the occurrence of zero-flux planes were studied in single-phase diffusion couples using a regular solution model for a hypothetical ternary system. Zero-flux plane for a component was observed to develop for diffusion couples at the composition that corresponds to the activity of that component in one of the terminal alloys. Morphological evolution of interphase boundary in solid-to-solid two-phase diffusion couples (fcc- vs. B2-) was examined in Ni-Cr-Al system with actual thermodynamic data and concentration dependent chemical mobility. With the instability introduced as a small initial compositional fluctuation at the interphase boundary, the evolution of the interface morphology was found to vary largely as a function of terminal alloys and related composition-dependent chemical mobility. In a binary Ni-Al system, multiphase diffusion couples of fcc- vs. L12-, vs. and vs. were simulated with alloys of varying compositions and volume fractions of second phase (i.e., ). Chemical mobility as a function of composition was employed in the study with constant gradient energy coefficient, and their effects on the final interdiffusion microstructure was examined. Interdiffusion microstructure was characterized by the type of boundaries formed, i.e. Type 0, Type I, and Type II boundaries, following various experimental observations in literature and thermodynamic considerations. Volume fraction profiles of alloy phases present in the diffusion couples were measured to quantitatively analyze the formation or dissolution of phases across the boundaries. Kinetics of dissolution of phase was found to be a function of interdiffusion coefficients that can vary with composition and temperature. The evolution of interdiffusion microstructures in ternary Ni-Cr-Al solid-to-solid diffusion couples containing fcc- and + (fcc+B2) alloys was studied using a 2D phase-field model. Alloys of varying compositions and volume fractions of the second phase () were used to simulate the dissolution kinetics of the phase. Semi-implicit Fourier-spectral method was used to solve the governing equations with chemical mobility as a function of compositions. The simulation results showed that the rate of dissolution of the phase (i.e., recession of two-phase region) was dependent on the composition of the single-phase alloy and the volume fraction of the phase in the two-phase alloy of the couple. Higher Cr and Al content in the alloy and higher volume fraction of in the alloy lower the rate of dissolution. Simulated results were found to be in good agreement with the experimental observations in ternary Ni-Cr-Al solid-to-solid diffusion couples containing and alloys. For the first time, a phase-field model was developed to simulate the diffusion process under an applied temperature gradient (i.e., thermotransport) in multiphase binary alloys. Starting from the phenomenological description of Onsager's formalism, the field kinetic equations are derived and applied to single-phase and two-phase binary system. Simulation results show that a concentration gradient develops due to preferential movement of atoms towards the cold and hot end of an initially homogeneous single-phase binary alloy subjected to a temperature gradient. The temperature gradient causes the redistribution of both constituents and phases in the two-phase binary alloy. The direction of movement of elements depends on their atomic mobility and heat of transport values.
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Date Issued
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2009
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Identifier
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CFE0002515, ucf:47658
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0002515
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Title
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The Evolution of Peristenus (Hymenoptera: Braconidae): Taxonomy, Phylogenetics and Ecological Speciation.
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Creator
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Zhang, Yuanmeng, Sharanowski, Barbara, Hoffman, Eric, Savage, Anna, Marcus, Jeffrey, University of Central Florida
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Abstract / Description
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Parasitoid wasps are ecologically and economically important as biological control agents. However, little is known about the diversity, distribution and biology of most hymenopteran parasitoids due to their small size, morphological conservatism, and complex life styles. The focus of my PhD research was to investigate the evolution and speciation of euphorine braconid wasps, using a combination of multilocus phylogenetics and population genomic techniques combined with traditional taxonomy....
Show moreParasitoid wasps are ecologically and economically important as biological control agents. However, little is known about the diversity, distribution and biology of most hymenopteran parasitoids due to their small size, morphological conservatism, and complex life styles. The focus of my PhD research was to investigate the evolution and speciation of euphorine braconid wasps, using a combination of multilocus phylogenetics and population genomic techniques combined with traditional taxonomy. The three data chapters of my dissertation are divided into different taxonomic ranks of euphorine braconids, focusing on genera, species, and populations. For chapter 2, I built a multilocus phylogeny of the tribe Euphorini with extensive taxa sampling around the globe. I confirmed the monophyly of Peristenus and Leiophron, two important biological control agents, and provided updated generic concepts and identification resources to aid applied researchers. In Chapters 3 and 4, I focused on cryptic species within the Peristenus pallipes complex in North America. I used an integrative taxonomic approach to resolve the taxonomic confusion within the Nearctic Peristenus pallipes complex (Chapter 3), then I used ddRADSeq to examine their evolutionary relationships with their Lygus hosts (Chapter 4). My dissertation provided a comprehensive analysis of Peristenus at multiple taxonomic ranks using phylogenetics and population genomics, providing insights into their evolutionary history that can be extrapolated into other groups of parasitoid wasps. The results from these studies also advanced our understanding of this group of animals of theoretical, economical, and conservation importance.
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Date Issued
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2018
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Identifier
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CFE0007272, ucf:52194
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007272
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Title
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Necessary Conditions for Open-Ended Evolution.
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Creator
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Soros, Lisa, Stanley, Kenneth, Gonzalez, Avelino, Wiegand, Rudolf, Cash, Mason, University of Central Florida
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Abstract / Description
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Evolution on Earth is widely considered to be an effectively endless process. Though this phenomenon of open-ended evolution (OEE) has been a topic of interest in the artificial life communitysince its beginnings, the field still lacks an empirically validated theory of what exactly is necessary to reproduce the phenomenon in general (including in domains quite unlike Earth). Thisdissertation (1) enumerates a set of conditions hypothesized to be necessary for OEE in addition to (2)...
Show moreEvolution on Earth is widely considered to be an effectively endless process. Though this phenomenon of open-ended evolution (OEE) has been a topic of interest in the artificial life communitysince its beginnings, the field still lacks an empirically validated theory of what exactly is necessary to reproduce the phenomenon in general (including in domains quite unlike Earth). Thisdissertation (1) enumerates a set of conditions hypothesized to be necessary for OEE in addition to (2) introducing an artificial life world called Chromaria that incorporates each of the hypothesizednecessary conditions. It then (3) describes a set of experiments with Chromaria designed to empirically validate the hypothesized necessary conditions. Thus, this dissertation describes the firstscientific endeavor to systematically test an OEE framework in an alife world and thereby make progress towards solving an open question not just for evolutionary computation and artificial life,but for science in general.
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Date Issued
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2018
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Identifier
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CFE0007247, ucf:52205
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0007247
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Title
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THE EVOLUTION OF U.S. CORPORATE LOGOS:A SEMIOTIC ANALYSIS.
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Creator
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Cowin, Erica, Matusitz, Jonathan, University of Central Florida
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Abstract / Description
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The purpose of this study is to examine the evolution of six U.S. corporate logos Apple, McDonald's, Nike, Pepsi, Shell, and Starbucks from each logo's inception until the newest version of the graphic emblem today. The objective is to determine the meanings that logos have for a corporation's identity, mission, and relationships, as well as the messages that logos convey to viewers (i.e., mostly customers). By "evolution" of logos here, the researcher means "ongoing transformation" of...
Show moreThe purpose of this study is to examine the evolution of six U.S. corporate logos Apple, McDonald's, Nike, Pepsi, Shell, and Starbucks from each logo's inception until the newest version of the graphic emblem today. The objective is to determine the meanings that logos have for a corporation's identity, mission, and relationships, as well as the messages that logos convey to viewers (i.e., mostly customers). By "evolution" of logos here, the researcher means "ongoing transformation" of logos. The semiotic model used in this analysis is Charles Sanders Peirce's (1958 ) semiotic framework. Peircean semiotics is made up of a three-part paradigm of signification: the representamen (or the sign itself), the object (or "referent" what the sign refers to), and the interpretant (the effect on the viewer, or the viewer's interpretation). Based on the semiotic data on logo evolution, the researcher found six main themes that emerged across the analyses of U.S. corporate logos. These themes are (1) Direction toward the Future, (2) Identity with Viewers, (3) Instant Recognition and Distinctiveness, (4) Consistency throughout Evolution, (5) Invocation of Change, and (6) True Representation of Corporate Identity. The ultimate conclusion of this analysis is that the communicative intent of a company, through its logo, tends to take a long time to develop. A successful logo is one that portrays the true objectives and principles of a company. For this reason, the ideal identity of a corporation tends to be built over a long period of time, which makes logo improvement "evolutionary" in nature. In all six cases, communication plays a major part in logo improvement.
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Date Issued
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2011
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Identifier
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CFE0003597, ucf:48885
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003597
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Title
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THE ORIGINS OF LACTASE PERSISTENCE AND ONGOING CONVERGENT EVOLUTION.
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Creator
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Keller, Beth, McIntyre, Matthew, University of Central Florida
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Abstract / Description
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As a primary factor in human evolution, natural selection is an important component of genetic research. Studies of lactase persistence suggest that positive selection has played a powerful role in the adaptation to a lifelong consumption of fresh milk. Using multiple research studies of lactase persistence and suspected corresponding single nucleotide genetic polymorphisms, this study combines data sources to determine whether evidence exists for natural selection of a specific cytosine-to...
Show moreAs a primary factor in human evolution, natural selection is an important component of genetic research. Studies of lactase persistence suggest that positive selection has played a powerful role in the adaptation to a lifelong consumption of fresh milk. Using multiple research studies of lactase persistence and suspected corresponding single nucleotide genetic polymorphisms, this study combines data sources to determine whether evidence exists for natural selection of a specific cytosine-to-thymine genetic mutation located 13,910 base pairs (T-13910) upstream from the lactase gene. This polymorphism has potential to be a causal element for lactase persistence, and data suggest that natural selection has played a role in the rising frequency and distribution of this allele, if only in some regions. European and neighboring regions appear to have the highest frequencies with little or no frequency in Asia, Africa and Indonesia; however the presence of lactase persistence in those areas suggests convergent evolution may be occurring on a phenotypic level. To examine this possibility several other identified polymorphisms in the same region as the T-13910 will be included in this study.
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Date Issued
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2011
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Identifier
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CFE0003608, ucf:48890
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003608
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Title
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MITIGATING MISBEHAVIOR IN WIRELESS NETWORKS: A GAME THEORETIC APPROACH.
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Creator
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Wang, Wenjing, Chatterjee, Mainak, University of Central Florida
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Abstract / Description
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In a distributed wireless system, multiple network nodes behave cooperatively towards a common goal. Though such assumptions on cooperation are desirable (e.g., controlling the transmit power level, reducing interference for each other, revealing private information, adhering to network policies) for analyzing and modeling, certain nodes belonging to a real-world system have often shown to deviate. These nodes, known as misbehaving nodes, bring more challenges to the design of the wireless...
Show moreIn a distributed wireless system, multiple network nodes behave cooperatively towards a common goal. Though such assumptions on cooperation are desirable (e.g., controlling the transmit power level, reducing interference for each other, revealing private information, adhering to network policies) for analyzing and modeling, certain nodes belonging to a real-world system have often shown to deviate. These nodes, known as misbehaving nodes, bring more challenges to the design of the wireless network because the unreliable channel makes the actions of the nodes hidden from each other. In this dissertation, we analyze two types of misbehavior, namely, selfish noncooperation and malicious attacking. We apply game theoretic techniques to model the interactions among the nodes in the network. First, we consider a homogeneous unreliable channel and analyze the necessary and sufficient conditions to enforce cooperative packet forwarding among a node pair. We formulate an anti-collusion game and derive the conditions that achieve full cooperation when the non-cooperative nodes collude. In addition, we consider multi-hop communication with a heterogeneous channel model. We refine our game model as a hidden action game with imperfect private monitoring. A state machine based strategy is proposed to reach Nash Equilibrium. The strategy attains cooperative packet forwarding with heterogeneous channel and requires only partial and imperfect information. Furthermore, it also enforces cooperation in multi-hop packet forwarding. To tackle the malicious attacks, we use Bayesian game analysis to show the existence of equilibrium in the detection game and argue that it might not be profitable to isolate the malicious nodes upon detection. We propose the concept of "coexistence with malicious nodes" by proving the co-existence equilibrium and derive the conditions that achieve the equilibrium. This research is further accomplished by extensive simulation studies. Simulation results illustrate the properties of the games and the derived equilibria. The results validate our design philosophy and clearly indicate that the proposed game theoretic solutions can be effectively used to enforce cooperation and mitigate attacks.
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Date Issued
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2010
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Identifier
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CFE0003080, ucf:48294
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0003080
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Title
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Worldwide Infrastructure for Neuroevolution: A Modular Library to Turn Any Evolutionary Domain into an Online Interactive Platform.
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Creator
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Szerlip, Paul, Stanley, Kenneth, Laviola II, Joseph, Wu, Annie, Kim, Joo, University of Central Florida
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Abstract / Description
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Across many scientific disciplines, there has emerged an open opportunity to utilize the scale and reach of the Internet to collect scientific contributions from scientists and non-scientists alike. This process, called citizen science, has already shown great promise in the fields of biology and astronomy. Within the fields of artificial life (ALife) and evolutionary computation (EC) experiments in collaborative interactive evolution (CIE) have demonstrated the ability to collect thousands...
Show moreAcross many scientific disciplines, there has emerged an open opportunity to utilize the scale and reach of the Internet to collect scientific contributions from scientists and non-scientists alike. This process, called citizen science, has already shown great promise in the fields of biology and astronomy. Within the fields of artificial life (ALife) and evolutionary computation (EC) experiments in collaborative interactive evolution (CIE) have demonstrated the ability to collect thousands of experimental contributions from hundreds of users across the glob. However, such collaborative evolutionary systems can take nearly a year to build with a small team of researchers. This dissertation introduces a new developer framework enabling researchers to easily build fully persistent online collaborative experiments around almost any evolutionary domain, thereby reducing the time to create such systems to weeks for a single researcher. To add collaborative functionality to any potential domain, this framework, called Worldwide Infrastructure for Neuroevolution (WIN), exploits an important unifying principle among all evolutionary algorithms: regardless of the overall methods and parameters of the evolutionary experiment, every individual created has an explicit parent-child relationship, wherein one individual is considered the direct descendant of another. This principle alone is enough to capture and preserve the relationships and results for a wide variety of evolutionary experiments, while allowing multiple human users to meaningfully contribute. The WIN framework is first validated through two experimental domains, image evolution and a new two-dimensional virtual creature domain, Indirectly Encoded SodaRace (IESoR), that is shown to produce a visually diverse variety of ambulatory creatures. Finally, an Android application built with WIN, #filters, allows users to interactively evolve custom image effects to apply to personalized photographs, thereby introducing the first CIE application available for any mobile device. Together, these collaborative experiments and new mobile application establish a comprehensive new platform for evolutionary computation that can change how researchers design and conduct citizen science online.
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Date Issued
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2015
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Identifier
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CFE0005889, ucf:50892
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0005889
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Title
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Assessment of Staphylococcus aureus Genetics: Clinical versus Community Epidemiology.
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Creator
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Lawrance, Matthew, Parkinson, Christopher, Savage, Anna, Cole, Alexander, University of Central Florida
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Abstract / Description
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Staphylococcus aureus has an historical relationship with anthropogenic environments, particularly hospitals, where infection characteristics differ from community-acquired disease. This has promoted a designation of strains as healthcare or community associated. Despite this affiliation, genetic approaches have failed to support these groupings. In order to establish the genetic relationship between S. aureus from differing anthropogenic environments, I have analyzed the relatedness between...
Show moreStaphylococcus aureus has an historical relationship with anthropogenic environments, particularly hospitals, where infection characteristics differ from community-acquired disease. This has promoted a designation of strains as healthcare or community associated. Despite this affiliation, genetic approaches have failed to support these groupings. In order to establish the genetic relationship between S. aureus from differing anthropogenic environments, I have analyzed the relatedness between three cohorts of S. aureus: nasal carriage isolates from community participants, infectious isolates from hospitals, and a cohort from an uninvestigated environment, an ambulatory clinic. Multilocus Sequence Typing (MLST) and Staphylococcus aureus protein a (spa) repeat regions were analyzed and the genetic relationships between cohorts at these sites were determined. I found high similarity in recovered sequences within and between all cohorts, with cohorts sharing 100% sequence identity across some samples. Phylogenetic reconstruction of the combined datasets indicate panmixia, with samples of all origins belonging to shared genetic lineages. Additional clustering algorithms supported this pattern. The findings of this study indicate that there is strong genetic similarity between both infectious strains and nasal carriage strains and between isolates from all cohorts. This research has implications for healthcare, as it demonstrates that S. aureus from differing environments are genetically similar (often identical), cautioning against delineating strains into nasal carriage or infectious based on origin. This research also informs the study of S. aureus evolution (-) strengthening the conclusion that differentiation at stably selected markers in lineages within differing 'healthcare habitats' is insufficient to explain observed phenotypic differences, and alternative explanations must be explored.
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Date Issued
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2016
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Identifier
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CFE0006534, ucf:51369
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0006534
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Title
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GENDERED VIRTUE: A STUDY OF ITS MEANING AND EVOLUTION IN EARLY MODERN FRANCE.
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Creator
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Saad, Mariela, Trinquet du Lys, Charlotte, University of Central Florida
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Abstract / Description
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Virtue in early modern France was a broad concept considered by clergymen, philosophers, and moralists as an instrument for measuring and implementing human ethics. This unprecedented research seeks to track the development of the notion of virtue from a gendered and dichotomous notion to a unique and undivided term. The word virtue is constantly present in French texts such as manuels de conduite1 , since the medieval period. Thus, it can be regarded as one of the most significant concepts...
Show moreVirtue in early modern France was a broad concept considered by clergymen, philosophers, and moralists as an instrument for measuring and implementing human ethics. This unprecedented research seeks to track the development of the notion of virtue from a gendered and dichotomous notion to a unique and undivided term. The word virtue is constantly present in French texts such as manuels de conduite1 , since the medieval period. Thus, it can be regarded as one of the most significant concepts defining genders in Western civilization. However, it is difficult for modern readers to grasp the complexity of the debate unless it is explained through its socio-historical and cultural implications regarding gender behavior. What is the author referring to when he/she uses the word virtue? Is it chastity for women, strength for men, or just the achievement of the highest moral standard? What are the social implications of virtue? Through an inter and multidisciplinary study involving literature, religion, philosophy, folklore, women and gender studies, and sociology, this cutting-edge research revolves around the literary analysis of conduct manuals, plays, novels and treatises, from the middle ages to the 18th century. Its objective is to map the evolution of the notion of virtue by evidencing social fluctuation of gender differences and conceptualizing our western civilization through the lenses of its moral discourse.
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Date Issued
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2016
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Identifier
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CFH2000146, ucf:45983
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFH2000146
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Title
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HIGH SPEED TURBO TCM OFDM FOR UWB AND POWERLINE SYSTEM.
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Creator
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WANG, YANXIA, Wei, Lei, University of Central Florida
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Abstract / Description
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Turbo Trellis-Coded Modulation (TTCM) is an attractive scheme for higher data rate transmission, since it combines the impressive near Shannon limit error correcting ability of turbo codes with the high spectral efficiency property of TCM codes. We build a punctured parity-concatenated trellis codes in which a TCM code is used as the inner code and a simple parity-check code is used as the outer code. It can be constructed by simple repetition, interleavers, and TCM and functions as standard...
Show moreTurbo Trellis-Coded Modulation (TTCM) is an attractive scheme for higher data rate transmission, since it combines the impressive near Shannon limit error correcting ability of turbo codes with the high spectral efficiency property of TCM codes. We build a punctured parity-concatenated trellis codes in which a TCM code is used as the inner code and a simple parity-check code is used as the outer code. It can be constructed by simple repetition, interleavers, and TCM and functions as standard TTCM but with much lower complexity regarding real world implementation. An iterative bit MAP decoding algorithm is associated with the coding scheme. Orthogonal Frequency Division Multiplexing (OFDM) modulation has been a promising solution for efficiently capturing multipath energy in highly dispersive channels and delivering high data rate transmission. One of UWB proposals in IEEE P802.15 WPAN project is to use multi-band OFDM system and punctured convolutional codes for UWB channels supporting data rate up to 480Mb/s. The HomePlug Networking system using the medium of power line wiring also selects OFDM as the modulation scheme due to its inherent adaptability in the presence of frequency selective channels, its resilience to jammer signals, and its robustness to impulsive noise in power line channel. The main idea behind OFDM is to split the transmitted data sequence into N parallel sequences of symbols and transmit on different frequencies. This structure has the particularity to enable a simple equalization scheme and to resist to multipath propagation channel. However, some carriers can be strongly attenuated. It is then necessary to incorporate a powerful channel encoder, combined with frequency and time interleaving. We examine the possibility of improving the proposed OFDM system over UWB channel and HomePlug powerline channel by using our Turbo TCM with QAM constellation for higher data rate transmission. The study shows that the system can offer much higher spectral efficiency, for example, 1.2 Gbps for OFDM/UWB which is 2.5 times higher than the current standard, and 39 Mbps for OFDM/HomePlug1.0 which is 3 times higher than current standard. We show several essential requirements to achieve high rate such as frequency and time diversifications, multi-level error protection. Results have been confirmed by density evolution. The effect of impulsive noise on TTCM coded OFDM system is also evaluated. A modified iterative bit MAP decoder is provided for channels with impulsive noise with different impulsivity.
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Date Issued
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2006
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Identifier
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CFE0000943, ucf:46745
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Format
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Document (PDF)
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PURL
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http://purl.flvc.org/ucf/fd/CFE0000943
Pages