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Long-Distance Movement In A Dusky Great Horned Owl And Limits To Phylogeography For Establishing Provenance, Robert W. Dickerman, Sabrina M. Mcnew, Christopher C. Witt Dec 2013

Long-Distance Movement In A Dusky Great Horned Owl And Limits To Phylogeography For Establishing Provenance, Robert W. Dickerman, Sabrina M. Mcnew, Christopher C. Witt

Western North American Naturalist

The Dusky Great Horned Owl (Bubo virginianus saturatus) of the Pacific Northwest region of North America is generally considered to be nonmigratory. Here we report a specimen of a Dusky Great Horned Owl that was salvaged in New Mexico and identified based on comparison of its plumage with a large series of museum skins. We attempted to corroborate this identification by comparing mitochondrial DNA sequences between the specimen and a representative sample of 5 Great Horned Owl subspecies from western North America. This analysis revealed minimal mitochondrial genetic variation and no evidence of population genetic structure, suggesting that …

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Seed-Feeding Beetles (Bruchinae, Curculionidae, Brentidae) From Legumes (Dalea Ornata, Astragalus Filipes) And Other Forbs Needed For Restoring Rangelands Of The Intermountain West, James H. Cane, Clarence Johnson, Jesus Romero Napoles, Douglas A. Johnson, Robert Hammon Dec 2013

Seed-Feeding Beetles (Bruchinae, Curculionidae, Brentidae) From Legumes (Dalea Ornata, Astragalus Filipes) And Other Forbs Needed For Restoring Rangelands Of The Intermountain West, James H. Cane, Clarence Johnson, Jesus Romero Napoles, Douglas A. Johnson, Robert Hammon

Western North American Naturalist

Seed-feeding beetles of the genera Acanthoscelides, Apion, and occasionally Tychiuswere commonly found occurring in seeds from wild populations of Astragalus filipesand Dalea ornata across rangelands of the United States Intermountain West, resulting in many new state, county, and host records. These 2 legumes, as well as other perennial herbaceous species, are being commercially farmed to produce seed supplies to rehabilitate sagebrush-steppe and adjoining juniper woodlands following wildfires. Most of the seeds examined in this study hosted one or more seed-feeding beetles; beetles that pupate and overwinter in the seeds pose the risk of being transported to storage warehouses …

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On The Edge: A Genetic Assessment Of Aplodontia Rufa From The Edge Of Their Distribution, Antoinette J. Piaggio, Jennifer Jeffers Dec 2013

On The Edge: A Genetic Assessment Of Aplodontia Rufa From The Edge Of Their Distribution, Antoinette J. Piaggio, Jennifer Jeffers

Western North American Naturalist

No abstract provided.

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Impact Of Livestock Grazing On Plant And Small Mammal Communities In The Ruby Mountains, Northeastern Nevada, Eric A. Rickart, Klaus G. Bienek, Rebecca J. Rowe Dec 2013

Impact Of Livestock Grazing On Plant And Small Mammal Communities In The Ruby Mountains, Northeastern Nevada, Eric A. Rickart, Klaus G. Bienek, Rebecca J. Rowe

Western North American Naturalist

We assessed the effects of livestock grazing on vegetation and small mammals in semiarid habitat at a site in northeastern Nevada. Habitat within a fenced exclosure that had been protected from grazing for more than 50 years supported more vegetation and had greater plant diversity compared to habitat immediately outside the exclosure. Likewise, species richness and abundance of small mammals were greater in ungrazed areas. Results suggest that grazing regulation in recent decades may account for some of the changes seen in regional plants and small mammals over the past century. The incorporation of long-term exclosures in a comparative framework …

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Insect Prey Eaten By Hoary Bats (Lasiurus Cinereus) Prior To Fatal Collisions With Wind Turbines, Ernest W. Valdez, Paul M. Cryan Dec 2013

Insect Prey Eaten By Hoary Bats (Lasiurus Cinereus) Prior To Fatal Collisions With Wind Turbines, Ernest W. Valdez, Paul M. Cryan

Western North American Naturalist

Wind turbines are being deployed all across the world to meet the growing demand for energy, and in many areas, these turbines are causing the deaths of insectivorous migratory bats. One of the hypothesized causes of bat susceptibility is that bats are attracted to insects on or near the turbines. We examined insect remains in the stomachs and intestines of hoary bats (Lasiurus cinereus) found dead beneath wind turbines in New York and Texas to evaluate the hypothesis that bats die while feeding at turbines. Most of the bats we examined had full stomachs, indicating that they fed …

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Influence Of Boulders On Netleaf Hackberry (Celtis Reticulata) Growth And Distribution In The Wasatch Foothills, Alex Argyle, Michael T. Stevens Dec 2013

Influence Of Boulders On Netleaf Hackberry (Celtis Reticulata) Growth And Distribution In The Wasatch Foothills, Alex Argyle, Michael T. Stevens

Western North American Naturalist

In a landscape, abiotic features, such as boulders, influence microhabitats and consequently affect patterns of vegetation. We hypothesized that boulders in the foothills of the Wasatch Mountains east of Provo, Utah, affected the growth patterns of netleaf hackberry (Celtis reticulata) by providing shade on their north faces. To test this hypothesis, we set up 3 transects 6 m wide and up to 50 m long. Along these transects, we measured all hackberries taller than 30 cm (n = 249). We recorded whether the hackberries grew within 0.5 m of a boulder that was at least 0.5 m …

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Ecology, Phylogenetics, And Conservation Of Draba Asterophora Complex: A Rare, Alpine, Endemic From Lake Tahoe, Usa, Emily Ruth Smith Putnam Dec 2013

Ecology, Phylogenetics, And Conservation Of Draba Asterophora Complex: A Rare, Alpine, Endemic From Lake Tahoe, Usa, Emily Ruth Smith Putnam

Theses and Dissertations

Rare, alpine, endemic species are particularly at risk for extinction. Alpine environments are especially vulnerable to climate change and human impacts, such as ski resort development and snowmaking. Draba asterophora Payson is a rare, alpine species that occurs only in three disjunct mountain-top regions surrounding Lake Tahoe. It is currently threatened by human impacts, such as ski resorts, as well as indirect influences of climate change and therefore in need of better understanding for conservation purposes. Draba asterophora may be able to serve as a case study for other similarly vulnerable, rare, alpine, endemic species with conservation needs. We utilized …

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Translation And Transcription Of A Passage From The Baduem Manuscript: An Eighteenth-Century Portuguese Embassy To China, Annalyn Beus Dec 2013

Translation And Transcription Of A Passage From The Baduem Manuscript: An Eighteenth-Century Portuguese Embassy To China, Annalyn Beus

Theses and Dissertations

This project is a diplomatic transcription and English translation of a passage from an 18-century manuscript that chronicles a remarkable Portuguese embassy to China (Macau). The embassy embarked from Lisbon in February 1752, sailing in a luxuriously outfitted ship (Nossa Senhora da Conceição e Lusitânia Grande), in convoy with a warship (Nossa Senhora das Brotas). The English translation is important because it makes the account accessible to scholars who lack familiarity with Portuguese.This voyage to China is remarkable in light of the long history of maritime loss by the Portuguese. Although the normal projected loss of life on this route …

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Nísia Floresta: Setting A Foundation For Feminist Literature In Brazil, Rachel Davidson Skinner Dec 2013

Nísia Floresta: Setting A Foundation For Feminist Literature In Brazil, Rachel Davidson Skinner

Theses and Dissertations

Many historians and literary critics recognize the nineteenth-century Brazilian author, Nísia Floresta, as the first feminist in Brazil. "Nísia Floresta é considerada a precursora dos ideais feministas no Brasil. Desde o início de sua carreira literária, a defesa dos direitos femininos foi o tema mais recorrente em sua obra"(Castro 250). Her works, published in Brazil and also in France and Italy, influenced women across borders. This thesis will address the discourse on maternity and education found in her works Opúsculo humanitário, Direitos das mulheres e injustiças dos homens, A mulher, and Conselhos à minha filha. Focusing on gender equality and …

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Post-Fire Interactions Between Soil Water Repellency, Islands Of Fertility, And Bromus Tectorum Invasibility, Kaitlynn Jane Fernelius Dec 2013

Post-Fire Interactions Between Soil Water Repellency, Islands Of Fertility, And Bromus Tectorum Invasibility, Kaitlynn Jane Fernelius

Theses and Dissertations

An intrinsic link exists between soil moisture and soil nitrogen. Factors that increase or decrease soil moisture can have a profound effect on soil nitrogen cycling, which may have later repercussions in the plant community. Post-fire soil water repellency is one factor that can limit soil moisture acquisition and may indirectly affect nitrogen cycling and weed invasion in woody islands of fertility. Plots centered on burned Juniperus osteosperma trees were either left untreated or treated with a surfactant to ameliorate water repellency. Two years later, soils were excavated from the untreated and treated field plots. In the greenhouse, half of …

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Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl Dec 2013

Liquid Core Waveguide Sensors With Single And Multi-Spot Excitation, Lynnell Uilani Wai Yee Zempoaltecatl

Theses and Dissertations

Using silicon based microfabrication and materials, a photonic platform, capable of single bioparticle analysis, has been developed. This platform combines liquid and hollow core waveguides on the micron-scale (5 µm x 12 µm) to isolate femtoliter sized sample volumes. Fluorescence excitation and signals in the visible range are directed into and out of the sample volume at an orthogonal angle to maximize signal-to-noise. In order to guide light in a low-index material antiresonant reflecting optical waveguides (ARROWs) were incorporated into the platform. This thesis reveals the development path of these structures over several device generations including innovations in material, geometries, …

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Certain Agave Species Exhibit The Capability To Be Moderately Productive Under Conditions Of High Salt And Drought Stress, Steven J. Bergsten Dec 2013

Certain Agave Species Exhibit The Capability To Be Moderately Productive Under Conditions Of High Salt And Drought Stress, Steven J. Bergsten

Theses and Dissertations

Water availability and arable lands are increasingly limiting resources in many parts of the U.S., particularly in semi-arid and arid regions. As a means of addressing food and fuel demands associated with burgeoning population growth, highly productive and water-use efficient crops need to be identified. One potential crop, Agave, merits consideration and evaluation due to its putative capability to provide sustenance and energy despite growing in water-limited regions and on marginal soils. However, little is known regarding the productivity these succulent plants will have under growing conditions of the Southwest, where high concentrated saline soils are abundant, and water is …

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Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell Dec 2013

Computational And Experimental Study Of Degeneration, Damage And Failure In Biological Soft Tissues, Gregory Allen Von Forell

Theses and Dissertations

The purpose of this work was to analyze the biomechanics of degeneration, damage, and failure in biological soft tissues both experimentally and computationally to provide insight into tendon or ligament tearing, tendo-achilles lengthening and lumbar spine dysfunction. For soft tissue tearing, experimental studies for calculating fracture toughness were performed and determined that tendons and ligaments are able to completely resist tear propagation. For tendo-achilles lengthening, a damage model was developed to mimic the behavior of the lengthening that occurs as a result of the percutaneous triple hemisection technique. The model provided insight for predicting the amount of lengthening that occurs …

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Molecular Modeling Of Dna For A Mechanistic Understanding Of Hybridization, Terry Jacob Schmitt Dec 2013

Molecular Modeling Of Dna For A Mechanistic Understanding Of Hybridization, Terry Jacob Schmitt

Theses and Dissertations

DNA microarrays are a potentially disruptive technology in the medical field, but their use in such settings is limited by poor reliability. Microarrays work on the principle of hybridization and can only be as reliable as this process is robust, yet little is known at the molecular level about how the surface affects the hybridization process. This work uses advanced molecular simulation techniques and an experimentally-parameterized coarse-grain model to determine the mechanism by which hybridization occurs on surfaces and to identify key factors that influence the accuracy of DNA microarrays. Comparing behavior in the bulk and on the surface showed, …

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Identification Of The Binding Partners For Hspb2 And Cryab Reveals Myofibril And Mitochondrial Protein Interactions And Non-Redundant Roles For Small Heat Shock Proteins, Kelsey Murphey Langston Dec 2013

Identification Of The Binding Partners For Hspb2 And Cryab Reveals Myofibril And Mitochondrial Protein Interactions And Non-Redundant Roles For Small Heat Shock Proteins, Kelsey Murphey Langston

Theses and Dissertations

Small Heat Shock Proteins (sHSP) are molecular chaperones that play protective roles in cell survival and have been shown to possess chaperone activity. As such, mutations in this family of proteins result in a wide variety of diseases from cancers to cardiomyopathies. The sHSPs Beta-2 (HspB2) and alpha-beta crystalline (CryAB) are two of the ten human sHSPs and are both expressed in cardiac and skeletal muscle cells. A heart that cannot properly recover or defend against stressors such as extreme heat or cold, oxidative/reductive stress, and heavy metal-induced stress will constantly struggle to maintain efficient function. Accordingly, CryAB is required …

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Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen Dec 2013

Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen

Theses and Dissertations

Nanomaterials have attracted substantial attention in the area of catalysis due to the unique properties they exhibit such as high surface areas, intricate pore networks and unique morphologies. TiO2 has attracted attention as a catalyst since the discovery of its high photocatalytic activity by Fuishima and Honda in 1972. Given its high thermal stability, low cost, low environmental impact, and versatility, TiO2 is a widely used commercial catalyst and catalyst support. TiO2 is used in many applications such as photocatalysis is also an excellent support material for noble metals in a number of oxidative synthesis and pollution-control reactions. Though TiO2 …

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Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson Dec 2013

Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a commonly used separation technique in chemistry. Nevertheless, the mechanistic interactions at the molecular level among the eluent, analyte, and the stationary phase are not fully understood. Because of this limited understanding, optimization of the separation must be done experimentally. Learning more about molecular interactions should aid in improving separations. We are currently using second-harmonic generation (SHG) spectroscopy to investigate how analytes adsorb to the surface. SHG is a spectroscopic technique that produces signal only at places of non-isotropic symmetry; this typically occurs at surfaces. SHG can be used to produce surface isotherms of test …

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Understory Vegetation Response To Mechanical Mastication Of Piñon And Juniper Woodlands, Jordan Ann Bybee Dec 2013

Understory Vegetation Response To Mechanical Mastication Of Piñon And Juniper Woodlands, Jordan Ann Bybee

Theses and Dissertations

Piñon and juniper encroachment and infilling can alter ecosystem processes and decrease resilience and resistance in sagebrush grasslands. Land managers employ a variety of techniques to eliminate these trees and mitigate their negative effects. Mechanical mastication or shredding is an increasingly popular method of removing these trees in Utah. It is a versatile treatment that can reduce canopy fuels, increase infiltration, and reduced sediment loss. We compared vegetation cover for annual and perennial vegetation functional groups on shredded and adjacent unshredded areas across a range of sites. Our approach was to categorize sites by ecological site type (encroachment or tree) …

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Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich Dec 2013

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich

Theses and Dissertations

Although phylloid algal mounds have been studied for 50 year, much remains to be determined concerning the ecology and sedimentology of these Late Paleozoic carbonate buildups. Herein we perform a digital outcrop study of the well-known Middle Pennsylvanian Lower Ismay mound interval in the Paradox Basin because outcropping mounds along the San Juan River are cited as outcrop analogs of reservoir carbonates in the Paradox Basin oil province of Utah and adjacent states. The principal field area is the Eight Foot algal field located at river mile 19.2 on the San Juan River, approximately 14 miles SSW of Bluff, Utah. …

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Remembering The Haitian Revolution Through French Texts: Victor Hugo's Bug-Jargal And Alphonse De Lamartine's Toussaint Louverture, Irene Joyce Kim Stone Dec 2013

Remembering The Haitian Revolution Through French Texts: Victor Hugo's Bug-Jargal And Alphonse De Lamartine's Toussaint Louverture, Irene Joyce Kim Stone

Theses and Dissertations

The Haitian Revolution was the first successful slave revolt in history. And even though Haiti declared independence from France in 1804, most French civilization textbooks do not include this important event. From an economic standpoint, France depended on its imports from Saint-Domingue (Haiti's pre-revolutionary name); and from a philosophical standpoint, the slave revolt in Saint-Domingue originated from ideas that came from French philosophers preaching the Rights of Man. Studying the Haitian Revolution within the context of the French Revolution provides a perspective that highlights the complex relationship between France and its colonies as well as religion's displaced role after 1789. …

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Pharmacokinetics Of Dexamethasone Delivered Via Iontophoresis, Justin Holbrook Rigby Dec 2013

Pharmacokinetics Of Dexamethasone Delivered Via Iontophoresis, Justin Holbrook Rigby

Theses and Dissertations

Study Design: Controlled laboratory study. Objectives: To determine the time course of dexamethasone sodium phosphate (Dex-P) iontophoresis delivery to underlying tissues using microdialysis. Background: The efficacy of iontophoresis at delivering Dex-P through the skin is unknown in humans because of the lack of minimally invasive measurement techniques. Methods: Sixty-four healthy male participants (age = 24.4 ± 3.3 yrs, height = 71.8 ± 2.5 in, weight = 181.8 ± 26.1 lbs) were randomly assigned into one of six groups: 1) 1 mA current, 1 mm probes depth ; 2) 1 mA current, 4 mm probes depth; 3) 2 mA current, 1 …

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Social Withdrawal During Adolescence And Emerging Adulthood, Julie C. Bowker, Larry J. Nelson, Andrea Markovic, Stephanie Luster Dec 2013

Social Withdrawal During Adolescence And Emerging Adulthood, Julie C. Bowker, Larry J. Nelson, Andrea Markovic, Stephanie Luster

Faculty Publications

Peer relationships are of central importance for healthy psychosocial development and functioning during childhood, adolescence, and adulthood. Peers provide unique opportunities for social-cognitive growth and the development and maintenance of social skills. They also serve as important sources of emotional and social support, can foster positive feelings about the self and others, and function protectively against the effects of interpersonal stressors (Rubin, Bukowski, & Parker, 2006). Without peer relationships, individuals might miss out on developmentally formative opportunities and experiences, such as acquiring certain socially competent skills and behaviors and forming intimate best friendships (Rubin, Coplan, & Bowker, 2009). It is …

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Evolving Art In Junior High, Randal Charles Marsh Dec 2013

Evolving Art In Junior High, Randal Charles Marsh

Theses and Dissertations

A junior high teacher and artist altered the curriculum of his Art Foundations II course and his own artistic practice in response to complexity thinking. This teacher-artist-researcher uses the arts-based methodology a/r/tography to make meaning of the relationship between his art and pedagogy. The a/r/tographer explains the impact of complexity on the philosophy of education, a/r/tography as a methodology, and the meaning making that occurred are included. Evolution was used as a methodology for art making and as constraint for developing artworks in the classroom and in the author's own art. The teacher-artist-researcher conceptualizes art as an emergent complex cultural …

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Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock Dec 2013

Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock

Theses and Dissertations

In this dissertation, methods to synthesize ZnO are reported. First, zinc oxide nanoparticles were synthesized with small amounts of transition metal ions to create materials called dilute magnetic semiconductors (DMS). We employed a low temperature sol-gel method that produces ZnO nanoparticles of reproducible size and incorporates cobalt, nickel, and manganese ions into the nanoparticles. Conditions were controlled such that a range of amounts of Co, Ni, and Mn were incorporated. The incorporation was tracked by color changes in the white ZnO powder to blue for Co, green for Ni and yellow for Mn. XRD measurements showed the nanoparticles were on …

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Methods And Metrics For Human Interaction With Bio-Inspired Robot Swarms, Sean C. Kerman Dec 2013

Methods And Metrics For Human Interaction With Bio-Inspired Robot Swarms, Sean C. Kerman

Theses and Dissertations

In this thesis we propose methods and metrics for human interaction with bio-inspired robot teams. We refine the concept of a stakeholder and demonstrate how a human can use stakeholders to lead a swarm as well as switch the swarm between different collective behaviors. We extend the human interaction metrics of interaction time and interaction effort presented in [1] to swarm systems and introduce the concept of interaction effort. These metrics allow us to understand how well the system performs under human influence. We employ systems theory to estimate these metrics, which is useful because this can be done without …

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The Effects Of Isolation On Endemic Cozumel Island Rodents: A Test Of The Island Rule, Brittany Marie Nuttall Dec 2013

The Effects Of Isolation On Endemic Cozumel Island Rodents: A Test Of The Island Rule, Brittany Marie Nuttall

Theses and Dissertations

Island isolation can cause changes in body size, cranial characteristics, and genetic variation in mammals. We use geometric morphometrics to test skull and mandible shape and size change across three species of endemic Cozumel Island rodents in order to test the “island rule” of larger size in isolated rodents. We also sequenced the D-Loop and cytochrome b region of the mitochondrial genome and tested for differences in genetic variation between island and mainland groups, as well as population structure and gene flow in order to assess the effect of island isolation on these three rodents. We found that the three …

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Application Of Next-Generation Transcriptomic Tools For Non-Model Organisms: Gene Discovery And Marker Developmentwithin Plecoptera (Insecta), Nicholas Gregory Davis Dec 2013

Application Of Next-Generation Transcriptomic Tools For Non-Model Organisms: Gene Discovery And Marker Developmentwithin Plecoptera (Insecta), Nicholas Gregory Davis

Theses and Dissertations

Phylogenetic research on non-model organisms has been hindered by limited marker availability. Next generation sequencing techniques are eliminating that barrier. Using Illumina sequencing technology, Trinity assembly software, custom Perl reciprocal BLAST scripts, and Primer3 primer prediction software, we produced and analyzed 7 Plecopteran transcriptomes, representing 7 of the 16 total families, in an attempt to identify and develop conserved orthologous genetic markers. The transcriptomes were used to reconstruct a gene content phylogeny using a simple distance matrix generated from reciprocal blastn data. By producing and filtering a reciprocal blast network we identified and aligned over 450 putative orthologs. Out of …

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Habitat Selection By Two K-Selected Species: An Application To Bison And Sage Grouse, Joshua Taft Kaze Dec 2013

Habitat Selection By Two K-Selected Species: An Application To Bison And Sage Grouse, Joshua Taft Kaze

Theses and Dissertations

Population growth for species with long lifespans and low reproductive rates (i.e., K-selected species) is influenced primarily by both survival of adult females and survival of young. Because survival of adults and young is influenced by habitat quality and resource availability, it is important for managers to understand factors that influence habitat selection during the period of reproduction. My thesis contains two chapters addressing this issue for K-selected species in Utah. Chapter one evaluates habitat selection of greater sage-grouse (Centrocercusurophasianus) on Diamond Mountain during the critical nesting and brood-rearing period. Chapter two address selection of birth sites by bison (Bison …

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Exploring Post-Fire Recovery Of Biocrusts And Desert Ecosystem Services, Jason R. Bahr Dec 2013

Exploring Post-Fire Recovery Of Biocrusts And Desert Ecosystem Services, Jason R. Bahr

Theses and Dissertations

Biocrusts and the ecosystem services they provide are becoming more susceptible to fire as exotic annual grass invasions facilitate the spread of desert wildfires. Further, precipitation patterns across the western United States are predicted to change over the next century, and have the potential to dramatically influence fire regimes and the recovery of burned biocrusts. Despite these changes to desert fire and precipitation cycles, our understanding of post-fire biocrust recovery is limited, especially regarding the first two years after fire. To investigate biocrust recovery, we created burn manipulations (i.e., unburned and burned) and tracked crust form and function over two …

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Importance Of Placement Depth In Evaluating Soil Nitrogen, Phosphorus, And Sulfur Using Ion Exchange Resin Capsules In Semi-Arid, Low Fertility Soils, Rachel Lynn Buck Dec 2013

Importance Of Placement Depth In Evaluating Soil Nitrogen, Phosphorus, And Sulfur Using Ion Exchange Resin Capsules In Semi-Arid, Low Fertility Soils, Rachel Lynn Buck

Theses and Dissertations

Ion exchange resin capsules provide a possible alternative to conventional soil testing procedures. Previous studies with semi-arid, low fertility soils observed poor relationships with poorly mobile nutrients such as phosphorus (P). We propose that placement depth may improve those relationships. Our objective was to (1) determine if placement depth could improve resin capsule estimation of the bioavailability of nitrogen (N), P, and sulfur (S) and (2) to determine if resin capsules can effectively estimate S availability in semi-arid, low fertility soils. Field sites were established in Rush and Skull Valleys, Utah on loam and sandy loam soils, respectively. Fertilizer was …

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