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The Functional Implications Of Anuran Metamorphosis For Survival, Locomotor Performance, And Limb Bone Mechanical Properties, Chase Kinsey Aug 2023

The Functional Implications Of Anuran Metamorphosis For Survival, Locomotor Performance, And Limb Bone Mechanical Properties, Chase Kinsey

All Dissertations

Many organisms must contend with navigating their environments from birth. An organism could be classified as – and is often studied – in the context of locomotion through a single habitat type. However, many organisms must contend with a wide variety of environmental obstacles and substrates. What’s more, a large group of animals, Lissamphibia, do so while undergoing drastic transformation of their morphology and locomotor appendages. This transformation, term metamorphosis, typically coincides with a movement from water as a tadpole, to land as a frog or salamander. Many studies have associated this transitionary period with decreased locomotor performance and worse …


Fabrication And Characterization Of Polymer Blends Containing Plant Oil-Derived Copolymers, Najah Mhesn Dec 2022

Fabrication And Characterization Of Polymer Blends Containing Plant Oil-Derived Copolymers, Najah Mhesn

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Growing environmental concerns associated with the production and disposal of traditional plastics, the depletion of non-renewable fossil resources, as well as pollution of landfills and the oceans have motivated researchers to pursue alternatives to petroleum-based materials. To this end, this research aims to develop environmentally friendly alternatives to petroleum-based plastics, thereby reducing the dependence on non-renewable resources. Namely, we report on the fabrication and characterization of polymer blends consisting of copolymers derived from soybean oil (as a minor phase) and matrix made from commercially available polymers: Polystyrene (PS) and Poly(lactic acid) (PLA). The copolymers employed in this work were obtained …


A Study On Effect Of Manufacturing Parameters On Morphology Of A356 Aluminum Foam, Nikhil Nanabhau Mahajan May 2022

A Study On Effect Of Manufacturing Parameters On Morphology Of A356 Aluminum Foam, Nikhil Nanabhau Mahajan

All Theses

Metal foams have shown an excellent promise for usage as multifunctional material concerning research & development in the last 20 years. They provide remarkable mechanical as well as physical properties being lightweight. Open-cell metal foams have already been used in sound and noise absorption. Open-cell metal foams are outstanding for use in heat exchangers, filters, and many more applications, while closed-cell foams show excellent characteristics in impact energy absorptions. Closed-cell metal foams have higher energy absorption than their solid parent metal as they convert most of the impact energy into deformation energy. Metal foams have been used as prominent safeguard …


Macroevolution Of Bold Color Patterns Across Teleostean Fishes, Katerina Zapfe Aug 2021

Macroevolution Of Bold Color Patterns Across Teleostean Fishes, Katerina Zapfe

All Theses

Fishes include some of the most visually striking vertebrate radiations and have repeatedly evolved bold color patterns, including bars, stripes, and spots. Such strong color patterns are hypothesized to provide multiple functions, including avoiding predation by obscuring recognizable features and communicating with others to secure territories and mates. Despite increasing focus on the functions and proximate drivers of color pattern evolution, the relevance of such pressures across broad taxonomic and time scales remain much less resolved. Using over 5000 species within the largest vertebrate radiation, teleostean fishes, I employ phylogenetic comparative methods to explore the lability and potential coevolutionary relationships …


Microfabricated Substrate To Achieve In Vivo-Like Cardiomyocyte Morphology And Electrical Propagation In Neonatal Cell Culture, Tiffany Yu Dec 2019

Microfabricated Substrate To Achieve In Vivo-Like Cardiomyocyte Morphology And Electrical Propagation In Neonatal Cell Culture, Tiffany Yu

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Because of the complexity of the in vivo environment, much physiological and pathological understanding of the human body is obtained through cell culture. To gain clinically relevant knowledge, having a cell culture model that mimics the corresponding in vivo tissue would be advantageous. For example, when studying the mechanical and electrical coupling between cardiac cells, imitating in vivo cellular morphology correlates with improved electrical coupling. This has applications within drug screening; by being able to test for cardiotoxicity with a cell culture model, this reduces the resources needed to screen pharmaceuticals for negative side effects. In conventional cardiomyocyte culture, cells …


Novel Ceria-Zirconia-Yttria Mesostructures: Synthesis, Characterization, Diffusional Studies And The Effects Of Morphology On Their Properties, Alma Cordova Morales Aug 2013

Novel Ceria-Zirconia-Yttria Mesostructures: Synthesis, Characterization, Diffusional Studies And The Effects Of Morphology On Their Properties, Alma Cordova Morales

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Ceria-zirconia-yttria (CZY) mixed oxides are used as catalyst supports for three-way catalysts for automotive exhaust emission control and in solid oxide fuel cells. By improving the morphology of CZY mesopores it is possible to reduce the sintering of supported noble metals and enhance overall catalyst lifetime and performance. However, limited studies have been published on the synthetic control of the morphology of CZY materials and the effects that CZY pore geometry has on catalyst operation.
To create optimized CZY catalyst supports, novel mesoporous CZY oxides were synthesized via classical sol-gel and evaporation induced self-assembly (EISA) methods, obtaining mesostructures that exhibited …


Advanced Imaging As A Novel Approach To The Characterization Of Membranes For Microfiltration Applications, Milagro Marroquin Aug 2013

Advanced Imaging As A Novel Approach To The Characterization Of Membranes For Microfiltration Applications, Milagro Marroquin

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This dissertation focuses on the design, development and implementation of novel, advanced imaging protocols for the characterization of membranes in microfiltration applications. Oftentimes, membrane characterization studies are done with high resolution microscopy techniques like scanning electron microscopy or transmission electron microscopy. The results obtained by these popular imaging techniques are subject to error and their reliability might be, in some instances, compromised because they require drying and metallization of the sample; working under high vacuum and electron beam intensity; and extensive sectioning to retrieve internal information. These factors may disrupt the membrane structure or modify its features. As an alternative …


Genetic And Environmental Determinants In The Evolution Of Alternative Mating Strategies In The Sailfin Molly, Poecilia Latipinna (Poeciliidae: Poecilia: Mollienesia), Elizabeth Lange Aug 2013

Genetic And Environmental Determinants In The Evolution Of Alternative Mating Strategies In The Sailfin Molly, Poecilia Latipinna (Poeciliidae: Poecilia: Mollienesia), Elizabeth Lange

All Theses

Understanding the genetic and environmental factors responsible for differences in size, morphology and behavior can aid in determining how alternative male mating strategies evolve in natural populations. One important environmental factor is nutrition, as it underlies growth of both body size and morphological traits that are linked to alternative mating strategies in many animals. In sailfin mollies, Poecilia latipinna , male size is fixed at maturity, highly variable within populations and correlated with dorsal fin morphology and expression of alternative male mating behaviors. Large males with exaggerated dorsal fins use courtship behavior while small males with reduced dorsal fins use …


The Inheritance Of Morphological And Behavioral Differences In The Mating Signals Of Sailfin And Shortfin Mollies, Stephanie Loveless Dec 2008

The Inheritance Of Morphological And Behavioral Differences In The Mating Signals Of Sailfin And Shortfin Mollies, Stephanie Loveless

All Theses

Changes in mating signals often result in the development of new species, thus, understanding the genetic basis of traits that confer pre-mating reproductive isolation can shed light on the speciation process. This study used interspecific hybridization between poeciliid fish, a sailfin molly (Poecilia velifera) and a shortfin molly (P. mexicana), to generate reciprocal F1 and backcross hybrids to investigate patterns of inheritance of traits that contribute to mating signal differences between these two groups of mollies. The first part of my study focused on behavioral differences in the mating system of sailfin and shortfin mollies. I observed mating behaviors of …


Revision Of The Males Of The Hydrospyche Scalaris Group In North America (Trichoptera: Hydropsychidae), James Korecki Dec 2006

Revision Of The Males Of The Hydrospyche Scalaris Group In North America (Trichoptera: Hydropsychidae), James Korecki

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The genus Hydrospsyche Pictet sensu stricto in North America is divided into three species groups, the Hydrospyche cuanis Ross Group Ross, the Hydropsyche depravata Hagen Group Ross, and the Hydropsyche scalaris Hagen Group Banks. Thirty-one of thirty-six described species are recognized in the Hydropsyche scalaris Group. Examination of adult males resulted in 5 junior subjective synonyms and one possible new species based on a single exemplar from Sevier County, Utah. Hydropsyche bidens Ross 1938, H. orris Ross 1938, and H. alvata Denning 1949 are junior synonyms of Hydropsyche incommoda Hagen 1861. Hydrospyche rossi Flint, Voshell and Parker, 1979 and H. …


Phylogeny Of Family Limnephilidae (Insecta: Trichoptera) With Emphasis On Tribe Limnephilini (Subfamily Limnephilinae), Tatyana Vshivkova Dec 2006

Phylogeny Of Family Limnephilidae (Insecta: Trichoptera) With Emphasis On Tribe Limnephilini (Subfamily Limnephilinae), Tatyana Vshivkova

All Dissertations

Morphological characters of adults and immature stages of Limnephilidae were analyzed with modern phylogenetic techniques, including traditionally used characters and some that have been poorly investigated or never studied. For the first time, monophyly is inferred for the following nominotypical taxa: superfamily Limnephiloidea, family Limnephilidae, subfamily Limnephilinae, tribe Limnephilini, and Limnephilus sensu stricto. Some other higher taxa are distinguished based on high bootstrap support, unreversed synapomorphies, and/or topography, including a new family-group category for Trichoptera, 'Branch,' more inclusive than the family category and less inclusive than the superfamily category. These new taxa in Limnephiloidea are as follows: Brachycentrida New Branch …