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I Just Can't Do It! The Effects Of Social Withdrawal On Prosocial Behavior, Ashley Michelle Fraser May 2012

I Just Can't Do It! The Effects Of Social Withdrawal On Prosocial Behavior, Ashley Michelle Fraser

Theses and Dissertations

While there has been research published on social withdrawal during childhood, little work has been done on the effects of social withdrawal during emerging adulthood. Since emerging adulthood is a time of transition and initiation to new environments and social contexts, it would be expected to be a time of great anxiety for individuals predisposed to social withdrawal (shyness). Shyer emerging adults are at risk for internalizing behaviors, lowered self-concept, and delayed entry into romantic relationships, therefore, they may also be more challenged when it comes to enacting prosocial behaviors. In addition, the inability to self-regulate emotions may mediate this …

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Relationship Between Observed Parental Optimism And Adolescent Optimism With Parental Involvement As A Mediating Variable: Two Wave Panel Study, Allison Ellsworth May 2012

Relationship Between Observed Parental Optimism And Adolescent Optimism With Parental Involvement As A Mediating Variable: Two Wave Panel Study, Allison Ellsworth

Theses and Dissertations

Using coded data from parent-child interaction tasks and questionnaires, this longitudinal study examined the relationship between observed mother and father optimism and self-reported and observed optimism of their adolescent child one year later with mother and father involvement as mediators. Results from structural equation modeling indicated that while there was not a direct association between maternal optimism and child optimism, that father involvement mediated that relationship, and that father involvement further mediated the relationship between father involvement and child optimism.

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Characterization Of Altered Epithelial Cell Turnover And Differentiation In Embryonic Murine Lungs That Over-Express Receptors For Advanced Glycation End-Products (Rage), Jeffrey Alan Stogsdill May 2012

Characterization Of Altered Epithelial Cell Turnover And Differentiation In Embryonic Murine Lungs That Over-Express Receptors For Advanced Glycation End-Products (Rage), Jeffrey Alan Stogsdill

Theses and Dissertations

Receptors for advanced glycation end-products (RAGE) are multi-ligand cell surface receptors highly expressed in the lung that modulate pulmonary inflammation during disease. However, the contributions of RAGE signaling are unknown during pulmonary organogenesis. In order to test the hypothesis that RAGE misexpression adversely affects lung morphogenesis, conditional transgenic mice were generated that over-express RAGE in alveolar type II cells of the lung. When RAGE is over-expressed throughout embryogenesis, severe lung hypoplasia ensues, culminating in perinatal lethality. Flow cytometry and immunohistochemistry employing cell-specific markers for various distal cell types demonstrated anomalies in key epithelial cell populations resulting from RAGE up-regulation through …

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Testing Crayfish Evolutionary Hypotheses With Phylogenetic Methods, Jesse W. Breinholt May 2012

Testing Crayfish Evolutionary Hypotheses With Phylogenetic Methods, Jesse W. Breinholt

Theses and Dissertations

This dissertation focuses on increasing the understanding of the evolution processes that have contributed to the diversification of freshwater crayfish. Chapter one estimates the divergence time of the three crayfish families and tests the hypothesis that diversification is tied to the break-up of Pangaea, Gondwanna, and Laurasia. I find that the families of crayfish diverged prior to or in association with the break-up of the three super continents. Chapter two addresses the evolutionary history of the genus Cambarus, using molecular data to test hypotheses of relationships based on chela and carapace morphology. The results provide evidence that the morphology used …

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Support Vector Machines For Classification And Imputation, Spencer David Rogers May 2012

Support Vector Machines For Classification And Imputation, Spencer David Rogers

Theses and Dissertations

Support vector machines (SVMs) are a powerful tool for classification problems. SVMs have only been developed in the last 20 years with the availability of cheap and abundant computing power. SVMs are a non-statistical approach and make no assumptions about the distribution of the data. Here support vector machines are applied to a classic data set from the machine learning literature and the out-of-sample misclassification rates are compared to other classification methods. Finally, an algorithm for using support vector machines to address the difficulty in imputing missing categorical data is proposed and its performance is demonstrated under three different scenarios …

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A Pressure Gauge Based On Gas Density Measurement From Analysis Of The Thermal Noise Of An Atomic Force Microscope Cantilever, Dongjin Seo, Mark R. Paul, Willian A. Ducker May 2012

A Pressure Gauge Based On Gas Density Measurement From Analysis Of The Thermal Noise Of An Atomic Force Microscope Cantilever, Dongjin Seo, Mark R. Paul, Willian A. Ducker

Faculty Publications

We describe a gas-density gauge based on the analysis of the thermally-driven fluctuations of an atomic force microscope (AFM) cantilever. The fluctuations are modeled as a ring-down of a simple harmonic oscillator, which allows fitting of the resonance frequency and damping of the cantilever, which in turn yields the gas density. The pressure is obtained from the density using the known equation of state. In the range 10–220 kPa, the pressure readings from the cantilever gauge deviate by an average of only about 5% from pressure readings on a commercial gauge. The theoretical description we use to determine the pressure …

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Refining Vibrationally-Resonant Sum Frequency Generation Spectroscopy For Studies Of Interfacial Interactions, Alexander D. Curtis May 2012

Refining Vibrationally-Resonant Sum Frequency Generation Spectroscopy For Studies Of Interfacial Interactions, Alexander D. Curtis

Theses and Dissertations

Many phenomena of interest to science and engineering occur at interfaces; however, access to, or discrimination of, interfacial interactions has been challenging, especially at buried interfaces. Vibrationally resonant sum-frequency generation (VR-SFG) spectroscopy is a powerful tool for investigating the molecular structure of free or buried interfaces, but spectral analysis has relied on many assumptions. To claim accurate new insights, practitioners must be able to make unique determinations from the data without experimental artifacts affecting the final results. For example, two independent and overlapping studies for the polystyrene/air interface were carried out, but reported different surface structures. Initially, this difference was …

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Mechanism Of Inhibition Of Influenza A Virus M2 Proton Channel, Douglas Randall Bretzing, Victoria Man-Fung Burr May 2012

Mechanism Of Inhibition Of Influenza A Virus M2 Proton Channel, Douglas Randall Bretzing, Victoria Man-Fung Burr

Faculty Publications

The influenza A virus integral membrane protein, M2, is a proton-conducting channel. The ability of influenza A virus to unpack its genome, replicate, and infect its host is contingent upon the M2-mediated acidification of the viral interior. The antiviral drugs amantadine and rimantadine were previously effective in blocking proton influx through M2; however, mutations in the proton channel have rendered these drugs ineffective. Multiple models for the inhibiting mechanism of the adamantane drugs have been hypothesized. In an attempt to better understand the mechanism of M2 inhibition, and ultimately to assist in the development of a replacement M2-targeting antiviral drug, …

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Italy At Home And Abroad After 150 Years: The Legacy Of Emigration And The Future Of Italianità, Mark I. Choate May 2012

Italy At Home And Abroad After 150 Years: The Legacy Of Emigration And The Future Of Italianità, Mark I. Choate

Faculty Publications

Shortly after unification in the Risorgimento, mass emigration stretched Italy in unforeseen ways, changing its culture, economics, and politics, and even its state, territory, language, and population. This enforced globalization polarized Italy and radically changed Italy as a nation-state and as a national culture. Controversies over emigration sharply divided Italian Liberals from the Nationalists and Fascists. The ideals of the nation-state, articulated by Mazzini, have been transformed by emigration in ways that have anticipated the twenty-first century global world. Today Italy faces similar challenges with rising immigration, together with the potential for constructive solutions.

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Iron Deficiency Causes A Shift In Amp-Activated Protein Kinase (Ampk) Catalytic Subunit Composition In Rat Skeletal Muscle, John Merrill Apr 2012

Iron Deficiency Causes A Shift In Amp-Activated Protein Kinase (Ampk) Catalytic Subunit Composition In Rat Skeletal Muscle, John Merrill

Theses and Dissertations

To determine effects of iron deficiency on AMPK activation and signaling, as well as the AMPKα subunit composition in skeletal muscle, rats were fed a control (C=50-58 mg/kg Fe) or iron deficient (ID=2-6 mg/kg Fe) diet for 6-8 wks. Their respective hematocrits were 47.5% ± 1.0 and 16.5% ± 0.6. Iron deficiency resulted in 28.3% greater muscle fatigue (p<0.01) in response to 10 min of stimulation (1 twitch/sec) and was associated with a greater reduction in phosphocreatine (C: Resting 24.1 ± 0.9 micromol/g, Stim 13.1 ± 1.5 micromol/g; ID: Resting 22.7 ± 1.0 micromol/g, Stim 3.2 ± 0.7 micromol/g; p<0.01) and ATP levels (C: Resting 5.89 ± 0.48 micromol/g, Stim 6.03 ± 0.35 micromol/g; ID: Resting 5.51 ± 0.20 micromol/g, Stim 4.19 ± 0.47 micromol/g; p<0.05). AMPK activation increased with stimulation in muscles of C and ID animals. A reduction in Cytochrome c and other iron-dependent mitochondrial proteins was observed in ID animals (p<0.01). The AMPK catalytic subunit (alpha) was also examined because both isoforms are known to play different roles in responding to energy challenges. In ID animals, AMPK alpha2 subunit protein content was reduced to 71.6% of C (p<0.05), however this did not result in a significant difference in resting AMPK alpha2 activity. AMPK alpha1 protein was unchanged, however an overall increase in AMPK alpha1 activity was observed (C: 0.91 pmol/mg/min; ID: 1.63 pmol/mg/min; p<0.05). Resting phospho Acetyl CoA Carboxylase (pACC) was unchanged. This study indicates that chronic iron deficiency causes a shift in the expression of AMPK alpha subunit composition and potentially altered sensitivity to cellular energy challenges.

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Species Identification And Strain Attribution With Unassembled Sequencing Data, Owen Eric Francis Apr 2012

Species Identification And Strain Attribution With Unassembled Sequencing Data, Owen Eric Francis

Theses and Dissertations

Emerging sequencing approaches have revolutionized the way we can collect DNA sequence data for applications in bioforensics and biosurveillance. In this research, we present an approach to construct a database of known biological agents and use this database to develop a statistical framework to analyze raw reads from next-generation sequence data for species identification and strain attribution. Our method capitalizes on a Bayesian statistical framework that accommodates information on sequence quality, mapping quality and provides posterior probabilities of matches to a known database of target genomes. Importantly, our approach also incorporates the possibility that multiple species can be present in …

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Joseph As Father In Guido Reni's St. Joseph Images, Alec Teresa Gardner Apr 2012

Joseph As Father In Guido Reni's St. Joseph Images, Alec Teresa Gardner

Theses and Dissertations

This study presents a psychoanalytic examination of Guido Reni's motivations for creating an innovative painting series of St. Joseph and the Christ Child. The seventeenth-century artist developed a new depiction of Joseph as the tender and loving surrogate father of Christ. This new artistic emphasis on the intimate relationship between father and son reveals Reni's own psychological need to create a replacement father. Indeed, contemporary biographers report that Reni suffered from anxiety and an aversion to women throughout his life. These odd behavioral traits appear to have stemmed from Reni's lack of a supportive father figure. Thus, the artist created …

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The Influence Of The Roman Atrium-House's Architecture And Use Of Space In Engendering The Power And Independence Of The Materfamilias, Anne Elizabeth Stott Apr 2012

The Influence Of The Roman Atrium-House's Architecture And Use Of Space In Engendering The Power And Independence Of The Materfamilias, Anne Elizabeth Stott

Theses and Dissertations

Architecture has a remarkable capacity to not only reflect social patterns and behaviors but to engender public image and identity. Therefore, it has proven to be a viable source for understanding the lives of ancient people. In fact, many scholars have established a connection between the atrium-house's design and the power and social identity of the paterfamilias, or male head of household. However, little has been said about what these same architectural features mean in relation to his female counterpart, the materfamilias. Therefore, this paper argues that the architecture of the atrium-house likewise engendered a sense of power …

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Using An Experimental Mixture Design To Identify Experimental Regions With High Probability Of Creating A Homogeneous Monolithic Column Capable Of Flow, Charles C. Willden Apr 2012

Using An Experimental Mixture Design To Identify Experimental Regions With High Probability Of Creating A Homogeneous Monolithic Column Capable Of Flow, Charles C. Willden

Theses and Dissertations

Graduate students in the Brigham Young University Chemistry Department are working to develop a filtering device that can be used to separate substances into their constituent parts. The device consists of a monomer and water mixture that is polymerized into a monolith inside of a capillary. The ideal monolith is completely solid with interconnected pores that are small enough to cause the constituent parts to pass through the capillary at different rates, effectively separating the substance. Although the end objective is to minimize pore sizes, it is necessary to first identify an experimental region where any combination of input variables …

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Vegetation Responses To Supplemental Winter Feeding Of Elk In Western Wyoming, Matthew J. Rinella, Ron Dean, Marty Vavra, Catherine G. Parks Apr 2012

Vegetation Responses To Supplemental Winter Feeding Of Elk In Western Wyoming, Matthew J. Rinella, Ron Dean, Marty Vavra, Catherine G. Parks

Western North American Naturalist

To compensate for losses in overwintering habitat, elk are fed hay in winter at approximately 37 locations throughout the western United States. These winter feeding programs concentrate elk activity, and there is concern that such concentrations could degrade plant communities. Except for one study focused exclusively on aspen (Populus tremuloides), ours is the first to quantify vegetation responses to supplemental winter feeding of elk. The western Wyoming feedground we studied was established in winter 1981–1982, and supplemental feeding occurred every winter through 2006. Transects were arranged in a before-after control-impact (BACI) design, and vegetation data were gathered in …

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Front Matter, Vol. 72 No. 1 Apr 2012

Front Matter, Vol. 72 No. 1

Western North American Naturalist

No abstract provided.

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End Matter, Vol. 72 No. 1 Apr 2012

End Matter, Vol. 72 No. 1

Western North American Naturalist

No abstract provided.

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A New Species Of Springsnail (Pyrgulopsis) From The Owyhee River Basin, Nevada, Robert Hershler, Hsiu-Ping Liu Apr 2012

A New Species Of Springsnail (Pyrgulopsis) From The Owyhee River Basin, Nevada, Robert Hershler, Hsiu-Ping Liu

Western North American Naturalist

We describe a new springsnail species, Pyrgulopsis cybele, from the Owyhee River basin (northwestern Nevada) based on morphologic and molecular (mtCOI) evidence.Pyrgulopsis cybele differs from other members of its genus in its unique pattern of penial ornament, which consists of small glands on the distal edge of the penial lobe, base of the penial filament, and outer edge of the medial section of the penis. It is further differentiated from regional congeners by its thickened inner-shell lip and mtCOI sequences. A Bayesian analysis based on COI data placed P. cybele in a well-supported clade that contained congeners from Snake …

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Intra-Annual Variation In Fish Communities And Habitat Associations In A Chihuahua Desert Reach Of The Rio Grande/Rio Bravo Del Norte, Thomas C. Heard, Joshuah S. Perkin, Timothy H. Bonner Apr 2012

Intra-Annual Variation In Fish Communities And Habitat Associations In A Chihuahua Desert Reach Of The Rio Grande/Rio Bravo Del Norte, Thomas C. Heard, Joshuah S. Perkin, Timothy H. Bonner

Western North American Naturalist

Anthropogenic alterations to lotic systems are often implicated in global declines among stream-dwelling fishes. A primary step toward mediating fish declines is improving our understanding of species–environment relationships; unfortunately, such information is limited. The goal of this study was to assess relationships between fish communities and environmental variables in a relatively intact portion of the Rio Grande / Rio Bravo del Norte in the southwestern United States and northern Mexico. We quantified the relationship between riverine habitats and local fish communities at 7 sites in the Big Bend reach of the Rio Grande / Rio Bravo del Norte during 2006. …

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Breeding Biologies, Pollinators, And Seed Beetles Of Two Prairie-Clovers, Dalea Ornata And Dalea Searlsiae (Fabaceae: Amorpheae), From The Intermountain West, Usa, James H. Cane, Melissa Weber, Stephanie Miller Apr 2012

Breeding Biologies, Pollinators, And Seed Beetles Of Two Prairie-Clovers, Dalea Ornata And Dalea Searlsiae (Fabaceae: Amorpheae), From The Intermountain West, Usa, James H. Cane, Melissa Weber, Stephanie Miller

Western North American Naturalist

Two prairie-clovers, Dalea ornata (Douglas ex Hook.) Eaton & J. Wright and Dalea searlsiae (A. Gray) Barneby, are perennial forbs found sporadically in the U.S. Intermountain West. Their seed is desirable for use in rangeland
restoration. We experimentally characterized the breeding biologies of D. ornata and D. searlsiae in a common garden, surveyed their pollinator guilds, and sampled their seed predators. The 2 Dalea species, being primarily xenogamous, have comparable pollination requirements. For flowers manually pollinated with outcross pollen, an average of 42% of D. ornata flowers and 39% of D. searlsiae flowers yielded plump large seeds filled with endosperm. …

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Do Populations Of An Invasive Weed Differ Greatly In Their Per-Gram Competitive Effects?, James E. Sowerwine, Matthew J. Rinella, Matthew L. Carlson Apr 2012

Do Populations Of An Invasive Weed Differ Greatly In Their Per-Gram Competitive Effects?, James E. Sowerwine, Matthew J. Rinella, Matthew L. Carlson

Western North American Naturalist

Quantifying an invasive species’ negative impacts across its introduced range will be quite challenging if the impacts vary unpredictably from site to site or from population to population. Little emphasis, however, has been placed on quantifying such interpopulation variation in the impacts of individual invasive species. We studied the response of a native grass (Festuca rubra) to competition from 4 geographically dispersed invasive plant (Melilotus albus) populations in order to determine if some populations of this invader have greater competitive impacts than others. Despite the relatively large number of experimental units in our greenhouse study, we …

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Shifting Prehistoric Abundances Of Leporids At Five Finger Ridge, A Central Utah Archaeological Site, Jacob L. Fisher Apr 2012

Shifting Prehistoric Abundances Of Leporids At Five Finger Ridge, A Central Utah Archaeological Site, Jacob L. Fisher

Western North American Naturalist

The faunal assemblage from Five Finger Ridge, an archaeological site in central Utah that was occupied by the Fremont from approximately AD 1100 to 1350, shows marked transitions in the relative abundances of 3 leporid taxa. At the time of initial occupation of the site, Sylvilagus audubonii and Lepus sp. dominated the assemblage but through time were gradually replaced by Sylvilagus nuttallii. I contextualized the shifting frequencies of these species using independent paleovegetation data. The data collectively suggest that the altitudinal range of the leporid species shifted during occupation of the site as a response to expanding pinyon-juniper woodlands.


El …

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Age And Growth Of Spawning Longnose Gar (Lepisosteus Osseus) In A North Central Texas Reservoir, Samuel W. Kelley Apr 2012

Age And Growth Of Spawning Longnose Gar (Lepisosteus Osseus) In A North Central Texas Reservoir, Samuel W. Kelley

Western North American Naturalist

The longnose gar (Lepisosteus osseus) is a primitive predaceous fish common throughout much of the east central United States, but research on its age and growth in lacustrine systems is rare. To characterize gar age and growth, I used bowfishing to collect spawning longnose gar in spring 2010 from littoral zones at Lake Arrowhead, Clay County, Texas. Females were older than males but significantly exceeded males in total length and mass when age was controlled. Von Bertalanffy growth curves suggested that males had faster growth rates, smaller maximum lengths, and shorter life spans than did females. However, females …

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Possible Effects Of Moss On Distribution And Performance Of A Threatened Endemic Primrose, Andrew P. Rayburn, Jacob B. Davidson, Hillary M. White Apr 2012

Possible Effects Of Moss On Distribution And Performance Of A Threatened Endemic Primrose, Andrew P. Rayburn, Jacob B. Davidson, Hillary M. White

Western North American Naturalist

Mosses may compete with vascular plants for limited soil resources, facilitate vascular plants by buffering extremes in abiotic conditions, and potentially trap seeds and provide safe sites for germination and establishment. We conducted a field study to investigate the effects of moss on the distribution and performance of Primula cusickiana var. maguirei, a threatened endemic perennial forb that occurs in an extremely narrow range within a single canyon in northern Utah, USA. Within the study population, we found that primroses occurred far more often on moss patches than on other substrates and that primroses occurring on moss patches had increased …

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Gopher Snake Searching Cliff Swallow Nests In East Central Utah, Nicholas J. Czaplewski, Kent S. Smith, John Johnson, Crystal Dockery, Brandon Mason, Ian D. Browne Apr 2012

Gopher Snake Searching Cliff Swallow Nests In East Central Utah, Nicholas J. Czaplewski, Kent S. Smith, John Johnson, Crystal Dockery, Brandon Mason, Ian D. Browne

Western North American Naturalist

We report details of a serendipitous encounter in July 2010 with a gopher snake (Pituophis catenifer) hunting in the mud nests of Cliff Swallows (Petrochelidon pyrrhonota). The swallow nests occurred beneath a deeply overhung sandstone cliff ledge in a box canyon of Ferron Creek in the shale deserts near Ferron, Emery County, Utah. The inaccessibility of the nests and the movement of the snake to and through them attest to both the extraordinary climbing ability of the gopher snake and the nest site selection and nest construction ability of the swallows.


Se presenta los detalles de …

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First Record Of The Cicada Tibicen Pruinosus In Colorado, With A Key To Colorado Species Of Tibicen (Hemiptera: Cicadidae), Brian Stucky Apr 2012

First Record Of The Cicada Tibicen Pruinosus In Colorado, With A Key To Colorado Species Of Tibicen (Hemiptera: Cicadidae), Brian Stucky

Western North American Naturalist

Tibicen pruinosus (Say)—a large, arboreal cicada typically found in the central United States—is reported for the first time from Colorado. This new state record represents a significant western extension of this cicada’s known range. Also reported are new records from Kansas that link the Colorado population to the previously known distribution of T. pruinosus. These results suggest that T. pruinosus has expanded its range westward, likely facilitated by human-induced changes in vegetation on the Great Plains. They also indicate the effectiveness of acoustic surveys as a tool for studying cicada distributions. Finally, an updated key including all 7 species of …

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Antibody Seroprevalence To Hantaviruses In Rodents From Reserva De La Biosfera Sierra De Huatla, Morelos, Elizabeth Arellano, Iván Castro-Arellano, Gerardo Suzán, Francisco X. González-Cózatl, Ricardo Morales Jiménez Apr 2012

Antibody Seroprevalence To Hantaviruses In Rodents From Reserva De La Biosfera Sierra De Huatla, Morelos, Elizabeth Arellano, Iván Castro-Arellano, Gerardo Suzán, Francisco X. González-Cózatl, Ricardo Morales Jiménez

Western North American Naturalist

No abstract provided.

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Obituary: Kimball Taylor Harper, 1931–2011, Renée Van Buren Apr 2012

Obituary: Kimball Taylor Harper, 1931–2011, Renée Van Buren

Western North American Naturalist

Obituary: Kimball Taylor Harper, 1931–2011

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Obituary: Wilmer Webster Tanner, 1909–2011, Stanley L. Welsh Apr 2012

Obituary: Wilmer Webster Tanner, 1909–2011, Stanley L. Welsh

Western North American Naturalist

Wilmer Webster Tanner, 1909–2011

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Captured: Lessons From Behind The Lens Of A Legendary Wildlife Photographer By Moose Peterson, Howard O. Clark Apr 2012

Captured: Lessons From Behind The Lens Of A Legendary Wildlife Photographer By Moose Peterson, Howard O. Clark

Western North American Naturalist

No abstract provided.

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