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Crystallographic Complex Reflection Groups and the Braid Conjecture

Description: Crystallographic complex reflection groups are generated by reflections about affine hyperplanes in complex space and stabilize a full rank lattice. These analogs of affine Weyl groups have infinite order and were classified by V.L. Popov in 1982. The classical Braid theorem (first established by E. Artin and E. Brieskorn) asserts that the Artin group of a reflection group (finite or affine Weyl) gives the fundamental group of regular orbits. In other words, the fundamental group of the space with reflecting hyperplanes removed has a presentation mimicking that of the Coxeter presentation; one need only remove relations giving generators finite order. N.V Dung used a semi-cell construction to prove the Braid theorem for affine Weyl groups. Malle conjectured that the Braid theorem holds for all crystallographic complex reflection groups after constructing Coxeter-like reflection presentations. We show how to extend Dung's ideas to crystallographic complex reflection groups and then extend the Braid theorem to some groups in the infinite family [G(r,p,n)]. The proof requires a new classification of crystallographic groups in the infinite family that fail the Steinberg theorem.
Date: August 2017
Creator: Puente, Philip C

Using Possible Selves to Examine the Impact of Internalized Stigma of Mental Illness on the Career Development of College Students with Hidden Disability

Description: The purpose of the study was to examine the impact of internalized stigma of mental illness on the career development of college students with hidden disabilities. The availability of research investigating career variables within this population is limited and is primarily focused within the vocational rehabilitation arena. Therefore, one of the goals of the current study was to link separate bodies of literature on college students with disabilities, career development, and internalized stigma of mental illness. The second goal was to examine the interaction of internalized stigma of mental illness between career decision self-efficacy and career exploration on the perceived likelihood of achieving hoped for occupational possible selves (OPS). The study included college students with hidden disabilities and investigated variables related to mental illness and career. Participants were administered a background information questionnaire, the Career Decision Self-Efficacy scale (CDSE-SF), selected subscales of the Career Exploration Survey (CES), and the Internalized Stigma of Mental Illness scale (ISMI). Contrary to hypotheses, career decision making self-efficacy, career self-exploration, and internalized stigma of mental illness did not have a direct effect on the perceived likelihood of achieving hoped for OPS. However, career environment exploration did have a direct and positive association with perceived likelihood of achieving hoped for OPS. Results further indicated internalized stigma of mental illness did not moderate the effect of career decision self-efficacy and career exploration on the perceived likelihood of achieving one's hoped for occupational self. Study implications, limitations, and future directions are discussed.
Date: August 2017
Creator: Campbell, Robyn

Reproduction and Metabolic Responses to Acute and Chronic Hypoxia in Ovoviviparous Blaberid Cockroaches, with a Focus on Blaptica dubia

Description: The major components of the tracheal system of insects are an extension of the exoskeleton, and the size of the exoskeleton is fixed in the adult stage, so any increase in metabolic demand that may accompany reproduction must be met by a relatively unaltered tracheal system that the female set in place at ecdysis, when entering adulthood. Acute hypoxia tends to elicit an increase in ventilation in insects, and here, I observe increased interburst VCO2 release, and a tendency towards a more continuous gas exchange pattern being preferred over discontinuous gas exchange when Blaptica dubia and Eublaberus posticus are exposed to a descending regime of hypoxia. Additionally, higher temperatures appear to increase sensitivity to hypoxia in these species, an expected result because both species, like most ectothermic animals, display a Q10 effect, increasing metabolic rates as temperature increases. The reproductive mode of B. dubia is considered to be lecithotrophic pseudoviviparity (or type A ovoviviparity), and by the time the embryos are born, they have more than doubles in volume from the time of oviposition. This gain is apparent in the wet mass of the embryo, with no change occurring in dry mass. The egg mass that can be attributed to water begins at 39% at oviposition and increased to nearly 82% at hatching. The metabolic rates of females and embryos increase as embryonic development progresses, but bomb calorimetry reveals that energy content of the embryos does not change. It is possible that these embryos gain some nutrition from the mother during embryonic development, but direct evidence remains to be demonstrated. Blaptica dubia and Eublaberus posticusare both blaberid species that display the same reproductive mode, pseudoviviparity, with incubation occurring in a brood sac. Comparisons between the reproductive traits of B. dubia and E. posticus reveal that the two species have similar ...
Date: August 2017
Creator: Mallery, Christopher Sean

The Impact of Observational Learning on Physical Activity Appraisal and Exertion Following Experimental Back Injury and the Role of Pain-Related Fear

Description: Chronic low back pain (CLBP) is one of the most prevalent and disabling health conditions in the US and worldwide. Biomedical explanations of acute injury fail to account for why some individuals experience remission of pain and restoration of physical function while others do not. Pain-related fear, accompanied by elevated appraisals of physical exertion and avoidance of physical activity, has emerged as a central psychosocial risk factor for transition from acute injury to chronic pain and disability. Research has indicated that these pain-related factors may be maintained through observational learning mechanisms. To date, no studies have experimentally examined the role of observational learning and pain-related fear in the context of actual musculoskeletal injury. Accordingly, the present study examined the impact of observational learning and pain-related fear on activity appraisals and exertion following experimentally- induced acute low back injury. Healthy participants' appraisal of standardized movement tasks along with measures of physical exertion were collected prior to and following a procedure designed to induce delayed onset muscle soreness (DOMS) to the lower back. Following induction of DOMS, participants observed a video prime depicting CLBP patients exhibiting either high or low pain behavior during similar standardized movements. In line with hypothesized effects, participants assigned to the high pain behavior prime demonstrated greater elevation in pain and harm appraisals as well as greater decrement in physical exertion. Further in line with hypotheses, significant changes in appraisal and physical performance following the high pain behavior prime were only observed among participants endorsing high pain-related fear during baseline assessment. Discussion of findings addresses potential mechanisms of action as well as study limitations and direction for future research.
Date: August 2017
Creator: Guck, Adam

A Convergence of LDPC Based on Eigenvalues

Description: Low-density parity check (LDPC) codes are very popular among error correction codes because of their high-performance capacity. Numerous investigations have been carried out to analyze the performance and simplify the implementation of LDPC codes. Relatively slow convergence of iterative decoding algorithm affects the performance of LDPC codes. Faster convergence can be achieved by reducing the number of iterations during the decoding process. In this thesis, a new approach for faster convergence is suggested by choosing a systematic parity check matrix that yields lowest Second Smallest Eigenvalue Modulus (SSEM) of its corresponding Laplacian matrix. MATLAB simulations are used to study the impact of eigenvalues on the number of iterations of the LDPC decoder. It is found that for a given (n, k) LDPC code, a parity check matrix with lowest SSEM converges quickly as compared to the parity check matrix with high SSEM. In other words, a densely connected graph that represents the parity check matrix takes more iterations to converge than a sparsely connected graph.
Date: August 2017
Creator: Kharate, Neha Ashok

Fabrication of Photonic Crystal Templates through Holographic Lithography and Study of their Optical and Plasmonic Properties in Aluminium Doped Zinc Oxide

Description: This dissertation focuses on two aspects of integrating near-infrared plasmonics with electronics with the intent of developing the platform for future photonics. The first aspect focuses on fabrication by introducing and developing a simple, single reflective optical element capable of high–throughput, large scale fabrication of micro- and nano-sized structure templates using holographic lithography. This reflective optical element is then utilized to show proof of concept in fabricating three dimensional structures in negative photoresists as well as tuning subwavelength features in two dimensional compound lattices for the fabrication of dimer and trimer antenna templates. The second aspect focuses on the study of aluminum zinc oxide (AZO), which belongs to recently popularized material class of transparent conducting oxides, capable of tunable plasmonic capabilities in the near-IR regime. Holographic lithography is used to pattern an AZO film with a square lattice array that are shown to form standing wave resonances at the interface of the AZO and the substrate. To demonstrate device level integration the final experiment utilizes AZO patterned gratings and measures the variation of diffraction efficiency as a negative bias is applied to change the AZO optical properties. Additionally efforts to understand the behavior of these structures through optical measurements is complemented with finite difference time domain simulations.
Date: August 2017
Creator: George, David Ray

John Playford's "The Division Violin": Improvisation and Variation Practice in English Violin Music of the Seventeenth Century

Description: English publisher John Playford (1623-1686/1687) first published his "The Division Violin: Containing a Collection of Divisions Upon Several Grounds for the Treble-Violin" in 1684. The first edition of this violin collection contains 26 written-out examples of improvisation, serving as a living snapshot of the performance practice of the time. This research is based on the second edition, which Playford had expanded into 30 pieces for the violin, published in 1685. The purpose of this study is to investigate the art of improvisation in England during the late 17th century, focusing on Playford's "The Division Violin." The dissertation first surveys the development of English violin music in the 17th century. Then, the dissertation traces eight selected 16th-century Italian diminution manuals. This will help readers understand the progression of the Italian diminution and improvisation practice in the 16th century and how it relates to the English division of the 17th century. Finally, based on a thorough research of the 17th-century improvisatory style and rhetorical approach, the author of this study provides performance suggestions on "Mr. Farinell's Ground," No. 5 from "The Division Violin."
Date: August 2017
Creator: Chan, Tzu-Ying

A Comprehensive Performance Guide for the Use of Advanced Technology in Euphonium Repertoire with Electronic Media through Analyses of Works by D. Edward Davis, Neal Corwell, and Lucy Pankhurst

Description: Solos for euphonium with electronic media present the unique challenge of incorporating an active, physical involvement in the live accompaniment through sound-altering technology such as guitar pedals or digital processors. Instructions for this solo genre are often vague and demand a general knowledge of how to use non-traditional devices. Due to the lack of information available on newly-composed pieces for this medium, students and professionals easily overlook the artistic merit of electroacoustic music. This dissertation provides a comprehensive performance guide that aids in the set-up and operation of advanced technology and presents a methodical approach to performing common musical and technical challenges found in modern euphonium repertoire with electronic media. Included in this dissertation are tables of common audio vocabulary and images of connectors, safety precautions, equipment recommendations with performance settings, a list of required connectors, adapters, cables, speakers, and amplifiers, performance set up diagrams, background information, and analyses of both the technical and musical aspects of each piece. In the appendices are signal flow charts, visual illustrations of polar recording patterns, and an updated catalog of published and unpublished original, adapted, and arranged euphonium solos with live electronics and electronic media accompaniment between 1970 and 2017.
Date: August 2017
Creator: Ray, Irving

Neurocognitive Effects of Gist Reasoning Training in Student-Athletes with Concussions, ADHD, and Learning Disabilities

Description: Concussions, attention-deficit disorder (ADHD), and learning disabilities can adversely impact learning and academic achievement, particularly with respect to attention, memory, and executive functioning; fortunately, cognitive training can be beneficial and remediating these weaknesses. One such program, strategic memory advanced reasoning training (SMART), utilizes a top-down approach to train individuals in executive, higher-ordered thinking strategies including strategic attention, integration, and innovation to facilitate information synthesis and enhance cognitive efficiency. Thus, the purpose of the study is to examine whether SMART improved performances on various neuropsychological measures tapping into attention, processing speed, memory, and executive functioning for college student-athletes with neurological conditions (e.g., concussions, ADHD, LD). Student-athletes were randomly assigned to the SMART program or a "wait-list" control group and were administered a neuropsychological battery at baseline, immediately following the intervention, and after a four-month delay. Results showed that participants benefited from SMART with respect to working memory immediately following the intervention after controlling for baseline scores. The benefits of working memory also persisted after four months. Additionally, SMART was beneficial for improving attention, but only after four months after the intervention. The findings of the current study were consistent with previous studies which showed positive effects of SMART on working memory with a variety of populations (e.g., children, adolescents, older adults, Veterans, brain-injured patients); however, the current study did not see improved performance on other aspects of executive functioning which contradict prior research. Statistical differences between the present study and prior research regarding SMART may be explained in methodology, participant characteristics, research setting, and/or limitations. Future studies may include combining cognitive training as the intervention and utilizing neuroimaging alongside cognitive training to examine the relationship between structural/functional change with neuropsychological performance.
Date: August 2017
Creator: Nguyen, Thomas

An Investigation of the Impact of Social Vulnerability Research on the Practice of Emergency Management

Description: This dissertation examines the extent to which social vulnerability, as studied by researchers across multiple disciplines, has influenced the practice of emergency management at the local level. This study addresses two major research questions to accomplish this goal. First, how do local emergency managers perceive and define social vulnerability? Second, what strategies do local emergency managers employ to reach and meet the needs of socially vulnerable populations? Semi-structured interviews were conducted in person or by phone with a sample of local emergency managers, city managers, and American Red Cross personnel from the Houston - Galveston and the South East Texas regions as defined by the respective Councils of Government. A modified grounded theory approach was used with a constant comparative method to identify themes for each research question. Triangulation was accomplished through secondary census data and supplemental interviews. The interview data reveal that social vulnerability research has had an indirect influence on the practice of emergency management at the local level. This influence is facilitated through state and federal policy, training, and plans development. Based on the interview data, four themes were identified that capture the various ways in which local emergency management officials perceive and define social vulnerability. These include vulnerability as poverty and culture, vulnerability as a lack of security, vulnerability as a moral imperative, and vulnerability as a lack of awareness and knowledge. In terms of strategies employed to address social vulnerability, the data suggest four themes: leaving it to the professionals, bringing in volunteers, leveraging protocols to build buy-in, and fostering flexibility. The findings reveal the importance in closing the knowledge gap between research and practice, because increased damage, harm, and death can occur when the social inequalities of everyday life are not addressed in the planning process by emergency managers. The findings also reveal that ...
Date: August 2017
Creator: Williams, Brian Don

Formation Control of Multi-Agent Systems

Description: Formation control is a classical problem and has been a prime topic of interest among the scientific community in the past few years. Although a vast amount of literature exists in this field, there are still many open questions that require an in-depth understanding and a new perspective. This thesis contributes towards exploring the wide dimensions of formation control and implementing a formation control scheme for a group of multi-agent systems. These systems are autonomous in nature and are represented by double integrated dynamics. It is assumed that the agents are connected in an undirected graph and use a leader-follower architecture to reach formation when the leading agent is given a velocity that is piecewise constant. A MATLAB code is written for the implementation of formation and the consensus-based control laws are verified. Understanding the effects on formation due to a fixed formation geometry is also observed and reported. Also, a link that describes the functional similarity between desired formation geometry and the Laplacian matrix has been observed. The use of Laplacian matrix in stability analysis of the formation is of special interest.
Date: August 2017
Creator: Mukherjee, Srijita

Professional Learning Communities: A Comparative Case Study of Shared Personal Practice

Description: Effective instructional practice has a significant impact on student learning. Shared personal practice within a professional learning team (PLT) is one of the key elements in consistently improved instructional practice. However, this PLT characteristic is often the least evident and the hardest to absorb into PLT culture. This study examined the relational characteristics, facilitating factors, or barriers to shared personal practice within a PLT. Two PLTs in core subject areas across two Texas high school campuses were included in this comparative case study. Data from document analysis, PLC observations, focus group interviews, and in-depth individual interviews were examined thematically to answer the research questions guiding this study. The results of this study revealed that building strong relationships and an emphasis on collective creativity were strong predictors of sharing personal practice. Collective clarity on PLT practices and the purpose of sharing personal practice increased the success and occurrence of sharing personal practice. The results also revealed that the copious tasks of teaching and negative perceptions of being observed by colleagues hindered consistent sharing of personal practice. This study describes the current context of shared personal practice as a foundation for future studies to examine how practice can be transformed.
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Date: August 2017
Creator: Curtis, Anna E

Neurological Responses to a Glucose Diet in Caenorhabditis elegans

Description: TRPV channels play a role in both mammalian insulin signaling, with TRPV1 expression in pancreatic beta-cells, and in C. elegans insulin-like signaling through expression of OSM-9, OCR-1, and OCR-2 in stress response pathways. In response to a glucose-supplemented diet, C. elegans are know to have sensitivity to anoxic stress, exhibit chemotaxis attraction, and display reduced egg-laying rate. Transcriptome analysis reveals that glucose stimulates nervous system activity with increased transcript levels of genes regulating neurotransmitters. Ciliated sensory neurons are needed for a reduced egg-laying phenotype on a glucose-supplemented diet. Egg-laying rate is not affected when worms graze on glucose-supplemented Delta-PTS OP50 E. coli, which is defective in glucose uptake. This suggests a possible sensory neuron obstruction by exopolysaccharides produced by standard OP50 E. coli on glucose, eliciting a starvation response from the worm and causing reduced egg-laying rate. Glucose chemotaxis is affected in specific TRPV subunit allele mutants: ocr-2(vs29) and osm-9(yz6), serotonin receptor mutants: ser-1(ok345) and mod-1(ok103), and G-alpha protein mutant: gpa-10(pk362). TRPV deletion mutants had no effect on glucose chemotaxis, alluding to the modality role pf TRPV alleles in specific sensory neurons. The role of serotonin in a reduced egg-laying rate with glucose remains unclear.
Date: August 2017
Creator: Dumesnil, Dennis

"Among the Voices Voiceless": Setting the Words of Samuel Beckett

Description: Among the Voices Voiceless is a composition for flute (doubling piccolo), clarinet (doubling bass clarinet), viola, cello, percussion, piano, and electronics, based on the poem "What would I do without this world faceless incurious" by Samuel Beckett. The piece is a setting for disembodied voice: the vocal part exists solely in the electronics. Having no physical body, the voice is obscured as the point of empathy for the audience. In addition, instrumental solos compete for focus during the work's twenty minute duration. In passages including a soloist, the soloist functions simultaneously as antagonist and avatar to the disembodied voice. Spoken word recordings and electronic manipulation of instrumental material provides further layers of ambiguity. The companion critical essay "Among the Voices Voiceless": Setting the Words of Samuel Beckett proposes the distillation of Beckett's style into the elements of prosaicness, repetition, fragmentation, ambiguity, and symmetry. Discussions of Beckett's works such as Waiting for Godot and Molloy demonstrate these elements in his practice. This framework informs the examination of two other musical settings of Beckett's poetry: Neither by Morton Feldman and Odyssey by Roger Reynolds. Finally, these elements are used to analyze and elucidate the compositional decisions made in Among the Voices Voiceless.
Date: August 2017
Creator: Lyszczarz, Joseph E

Developing a Self-Respect Instrument to Distinguish Self-Respect from Self-Esteem

Description: Throughout the scientific literature, researchers have referred to self-respect and self-esteem as being the same construct. However, the present study advocated that they exist as two distinct constructs. In this quantitative study, an instrument was developed to measure self-respect as a construct, and subsequently distinguish that self-respect is distinct from the construct of self-esteem. Exploratory factor analyses (EFA) indicated 32.60% of the variance was accounted for by the 11-item Jefferson Self-Respect instrument (JSR), which measured self-respect as a unidimensional construct. The reliability estimate of the scores from the JSR reached an acceptable α = .82. Fit indices (RMSEA = .031, SRMR = .037, CFI = .982, and TLI = .977) from the confirmatory factor analyses (CFA) signified a well-fitted hypothesized model of self-respect that existed as a unidimensional construct. Additionally, the CFA revealed that the construct of self-respect, and self-esteem was generally distinct, and the strength of the correlation between the two constructs was moderately positive (r = .62).
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Date: August 2017
Creator: Jefferson, Sean G

Comparison of the "Méthode Pour La Guitare" by Fernando Sor with the "Méthode Complète Pour La Guitare Par Ferdinand Sor, Rédigée Et Augmentée De Nombreux Exemples Et Leçons Suivis D'une Notice Sur La 7e Corde" by Napoléon Coste

Description: The nineteenth century presents a great increase in publications of guitar methods. Most authors of the time published several versions of their works. Fernando Sor, perhaps the most prominent guitar composers of the time—whose Méthode is regarded today as the most important of the period—only published one edition. However, Napoleon Coste took on the task to do a second account. The literature reviewed shows substantial existing information regarding background, type of text, tone, and contents of Sor's work, but comparisons to date are not substantial. Therefore, there is a need to compare these two texts side by side to yield a complete view of their pairing. The existing negative views of Coste's edition hinder the importance of Coste's work as reference to Segovia's publication of Sor studies, and as a clearer pedagogical application of many of Sor's concepts which are sidetracked by his response to criticism and his elaborations in matters beyond his main subject matter. I provide a comprehensive review of Sor's method, an outline and a consideration of his concepts. Then I offer a complete English translation of Coste's method which is inexistent until now. The comparison follows pointing at differences and similarities. Results show that Coste clarifies and complements many of the principles in less text and simpler language. He modifies certain others either to approach Sor's practice or to depart to a newer standard. He offers his own lessons and sections to apply Sor's concepts. Coste's text heads towards a pedagogical synthesis of Sor's method, but it is incomplete because he omits some concepts without leading the readers to consult Sor. Coste's pedagogical and practical relevance is fundamental for modern standard techniques.
Date: August 2017
Creator: Rodriguez, Sergio

Music With and Without Lyrics Increases Motivation, Affect, and Arousal during Moderate-Intensity Cycling

Description: Music is used to distract, energize, and entertain during exercise by producing positive psychological and physiological responses. Specifically, listening to music during exercise enhances performance, increases motivation, improves affect, and optimizes arousal. Researchers have identified several elements of music that may moderate this relationship, including lyrics. However, few studies to date have examined the influence of motivational lyrics on psychological and physiological states during exercise. Thus, the primary purpose was to investigate the effects of lyrics in music on motivation, affect, arousal, and perceived exertion during moderate intensity cycling. Thirty (Mage = 21.0 ± 2.9 years old) college-aged individuals performed three, 8-min acute bouts of moderate-intensity exercise on a cycle ergometer during music with lyrics (ML), music without lyrics (MNL), and no music control (MC) conditions. Measures of motivation, affect, arousal, and perceived exertion were taken before and after a 6-min warm-up, every 2-min during the exercise bout, and following a 2-min cool-down. For ML and MNL conditions, participants reported higher motivation, affect, and arousal during exercise relative to the MC condition. As expected, RPE increased throughout the exercise period, with no condition differences observed. Additionally, there were no differences in responses between the ML and MNL conditions. Collectively, these results suggest that music, regardless of lyrical content, can enhance psychological responses during exercise. The current findings may help address common exercise barriers and inform exercise practitioners on music selection to improve exercise adherence.
Date: August 2017
Creator: Marshall, Daniel N

Elections and Authoritarian Rule: Causes and Consequences of Adoption of Grassroots Elections in China

Description: This dissertation investigates the relationship between elections and authoritarian rule with a focus on the case of China's adoption of elections at the grassroots level. In this dissertation, I look at the incentives facing Chinese local governments in choosing between holding competitive elections or state-controlled elections, and how the selection of electoral rules shapes the public's preferences over political institutions and influences the citizens' political behaviors, especially voting in elections and participation in contentious activities. The overarching theme in this dissertation proposes that the sources and consequences of Chinese local elections are conditioned on the state-owned resources and the governing costs. When the amount of state-owned resources to rule the local society is limited, the paucity of resources will incentivize authoritarian governments to liberalize grassroots elections to offset the governance costs. The various levels of election liberalization will lead to different consequences in the public's political behavior. An abundance of state-owned resources not only discourages rulers from sharing power with the local society, but also supplies the rulers with strong capacity to obtain loyalty from voters when elections are adopted. As a result, elections under authoritarian governments with an abundance of state-owned resources will see more loyalist voters than elections with authoritarian governments with fewer state-owned resources. In addition, the varieties of election practices will exert impacts on public opinion toward the authoritarian government: awareness of elections will enhance public trust in the government and decrease the public's intention to challenge the incumbents' authority while at the same time increasing the public's faith in the institutions, thereby encouraging the public to adopt official channels to air their grievances. The analysis of the village-level as well as individual-level survey data and cases lends empirical supports to the argument. First, I find that the governing costs—measured by the size of labor force—are ...
Date: August 2017
Creator: Tzeng, Wei Feng

The Role of Thyroid Hormone across Avian Development Spectrum: Investigations on Systemic Development, Metabolism and Ontogeny of Endothermy

Description: Achievement of endothernic capacity is vital for independence from ambient temperature changes, sustained activity, optimal biochemical reactions and optimization of parental care. During early avian development, the core tenets of transition from ectothermy to endothermy are development of metabolic capacity (oxygen consumption, mitochondrial bioenergetics), enhanced cardiovascular function (heart rate and cardiac output), pulmonary ventilation and thermogenic capacity. Thyroid hormones, particularly T3, are key metabolic regulators of basal metabolism, thermogenesis, pulmonary ventilation and mitochondrial respiration. Thyroid hormone fluctuation patterns during both precocial and altricial avian endothermic transition suggest a prominent role in maturation of endothermy, cardiovascular, respiratory and skeletal muscle physiology. This body of work explores effects of T3 manipulations in two avian species: the precocial Pekin duck and the altricial Red-winged Blackbird. Increased plasma T3 during late incubation resulted in increased cardiac mass, elevated resting and intrinsic heart rate, intrinsic mean arterial pressure, increased cholinergic tone and blunted alpha-adrenergic tone in the precocial Pekin duck. In both Pekin duck and Red-winged blackbird, plasma T3 levels correlated with changes in the trajectory of endothermic ontogeny, systemic oxygen consumption, thermogenesis, maturation of pulmonary ventilatory function, altered growth and effects on skeletal and cardiac mitochondrial bioenergetics. These observations support the role of thyroid hormones as metabolic and developmental regulators at the time of attainment of endothermy during the perinatal period in precocial and altricial avian species. Insights into the role of thyroid hormone as a metabolic and development regulator at the time of avian endothermic attainment provide a more thorough understanding of metabolic and physical transitions a hatchling bird must undergo to reach the adult endothermic phenotype. Such insights also deepen understanding of the complex role thyroid hormones play in homeostasis and offer implications about the evolutionary history of endothermic capacity.
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Date: August 2017
Creator: Sirsat, Tushar S

Size Framing: Conceptualization and Applications in Consumer Behavior

Description: Size information is vital in many consumer contexts, but currently, no central framework or conceptual model exists for a thorough understanding of the underlying process of how consumers interpret size information and form size judgments. Thus, the purpose of this three-paper dissertation is to introduce such a framework, discuss future research directions based on that framework, and pursue a few of these directions in the second and third papers, both of which focus on a vanity sizing context. The resulting work and findings illustrate the process through which consumers go in forming size judgments and collectively present both scholars and practitioners with a common basis for future study and implementation of findings in contexts in which size information is salient.
Date: August 2017
Creator: Ketron, Seth Christopher

The Role Humor Plays in Facilitating Rapport, Engagement, and Motivation in Graduate Online Learning Environments

Description: This study seeks to explore, using an interpretivist phenomenological approach, how humor may impact rapport, engagement, and motivation in graduate online learning environments. Through detailed qualitative analysis of semi-structured interviews, direct observation, and demographic survey data, emergent themes were identified that support the use of appropriate humor to create a positive online environment in which learning can take place. Evidence indicates that humor, when used purposefully and appropriately, is a valuable tool for promoting rapport and engagement amongst course members through community-building and enhanced interpersonal connections. The results of this study reveal the importance of finding common ground and shared experiences to improve the overall social and communicative culture of an online course. The results also support the idea that online instructors should make a great effort in connecting with students in online courses and must make a greater effort to appropriately engage in their online courses. Appropriate recommendations are made for practical application of humor to support pedagogy, as well as recommendations for future research on humor in educational environments.
Date: August 2017
Creator: Steele, James

Nightmare Disorder Prevalence as Defined by the DSM-5 in a College Sample

Description: The nightmare prevalence literature to date has largely focused on nightmare episode severity (i.e. frequency), with 8%-87% of individuals reporting these events in the past week to year. While this has helped to determine the prevalence of these events, focus on the episode severity alone is problematic because it means little is known about the actual prevalence of nightmare disorder. Moreover, focus on episode severity likely overestimates the actual prevalence of clinically significant nightmares while also obscuring clinically significant consequences of the disorder. Understanding the prevalence of nightmare disorder can help guide treatment planning and interventions. The present study recruited UNT undergraduates (N = 372; 351 analyzed) and managed all participant data using Research Electronic Data Capture (REDCap). The present study aimed to determine the prevalence of nightmare disorder, as stated in the DSM-5, to facilitate accurate characterization of the disorder. Additionally, as part of the secondary aim the influence of gender on nightmare disorder status and psychological wellbeing as measured by psychological and sleep outcome variables was examined. Finally, comparisons of individuals with DSM-5-defined nightmare disorder to those without the disorder were conducted on previously examined correlates (e.g., trauma symptoms, depression).
Date: August 2017
Creator: Estevez, Rosemary

Extended String Techniques and Special Effects in Arnold Schoenberg's String Quartet No. 1 and Its Significance in Chamber Music Literature

Description: Arnold Schoenberg's String Quartet No. 1, Op. 7 stands out as being the first chamber music piece to use a vast number and variety of extended string techniques within one composition. This paper examines a brief history of extended string techniques in chamber music, analyses the unique ways in which Schoenberg applied extended string techniques to manipulate motives in his Op. 7 quartet, and ultimately shows that Schoenberg's use of extended string techniques influenced future composers to employ even more extended techniques and special effects in their own twentieth-century chamber music.
Date: August 2017
Creator: Greenfield, Leah Luke

Trajectories of Burden and Depression in Caregivers Following Traumatic Injury: The Role of Resilience

Description: As part of an effort to understand psychological consequences among family members of patients sustaining a traumatic injury, medical research has turned to the role of resilience – or the ability to bounce back from and maintain psychological well-being in the wake of an adverse event— in mitigating the potential distress (i.e., depression and burden) of caregiving (Bonanno, 2004; Roberson et al., under review). This study sought to examine the ability for trait-resilience to predict trajectories of distress over the course of a year among 124 family members and loved ones of patients admitted to a Level I Trauma Center. A cross-lagged path model examining resilience, burden, and depression at baseline, 3, 6, and 12 months after injury showed that, while depression strongly predicted later burden, resilience was not a significant predictor of either outcome in the model. When depression and burden were subjected to a person-centered analysis (i.e., latent growth curve analysis), two major classes were identified: caregivers with high, chronic distress (33% of the sample) and low-moderate distress that declined over time. A three-class solution for caregiver burden further identified a moderate, increasing trajectory class. Predictive discriminant analyses revealed that trait-resilience was a major differentiating trait between class membership (rs = .23 for depression; rs = .32 for burden); further, presence of PTSD symptoms at baseline, gender, and history of depression were shown to be strong factors in distinguishing class membership across both outcomes. This study helps shed insight into the well-being of caregivers in the wake of a loved one's traumatic injury, in addition to possible identifying risk factors while patients are still admitted in the ICU. Lastly, the study provides alternatives for analyses that focus on longitudinal outcomes, particularly person- vs. variable-centered solutions.
Date: August 2017
Creator: Agtarap, Stephanie D