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Static Bustle: Patterns Achieved Through Repetitive Processes (Artists Statement)

Description: Static Bustle is a gradute work that explores relationships between visual art and sound through experiments with new and traditional media, including sound, video, digital images prints and fibers. Through strategic processes of layering and repetition, the researcher seamlessly unifies this remarkable range of media into an accessible and cohesive vision. Overall, this research shows visual and sonic pattern achieved through repetitive processes.
Date: May 2015
Creator: Vogt, Jonathan C.
Partner: UNT Libraries

The Impact of End-user Decision-making in the Supply of Public Transportation

Description: Efficient public transportation provides economic and social opportunities that increase accessibility to markets and employment as well as providing investment benefits. Key challenges to the U.S. public transportation industry include developing modes and increasing the availability of public transportation in a manner that meets the needs of individual users in a cost effective manner. A problem facing public transportation officials is the need to understand the factors that influence consumer decision-making and consumer attitudes toward public transportation. Feedback regarding experiences as well as expectations from commuters provides information for developing and improving public transportation. Thus, decision-making factors of end-users are keys to improving supply, growth, and understanding utilization of public transportation. Public transportation officials seek to improve the public transportation experience for commuters by increasing modes and benefits of the systems. The decision-making factors of the end-users require identification and examination in order to provide a high quality and efficient experience for commuters. The research questions of interest in the current dissertation are: (1) What are the decision-making factors affecting commuters’ attitudes toward public transportation? and (2) How do the end-user decision-making factors affect the supply of public transportation? The purpose of this research is to extend the current body of knowledge about decision-making factors by developing and testing a new theoretical model to measure the attitudes of public transportation end-users. This study has its theoretical foundation in the theory of planned behavior, theory of reasoned action, and rational choice theory. To understand how public transportation is affected by decision-making factors, it is necessary to analyze the relationships among the decision factors and attitudes. The findings of this study contribute by building theory and having implications for practice. This study employs a mixed methodology of qualitative and quantitative research. More specifically, the development of a framework and testing of that ...
Date: May 2015
Creator: Scott, Rebecca A.
Partner: UNT Libraries

Tonality and the Extended Common Practice in the Music of Thad Jones

Description: Tonality is a term often used to describe the music of the common practice period (roughly 1600-1900). This study examines the music of mid twentieth-century jazz composer Thad Jones in light of an extended common practice, explicating ways in which this music might be best understood as tonal. Drawing from analyses of three of Jones’s big band compositions: To You, Three and One, and Cherry Juice, this study examines three primary elements in detail. First is Jones’s use of chord-scale application techniques in the orchestration over various chordal qualities represented by the symbols, revealing traditional as well as innovative methods by Jones. Second is Jones’s use of harmonic progressions, demonstrating his connection to past practice as well as modern jazz variations. Third is Jones’s use of contrapuntal connections and their traditional relationship to functional tonality, but in a chromatic scale-based environment. Jones’s music is presented in this study to demonstrate a tonal jazz common practice that represents an amalgamation of traditions including twentieth-century scale-based procedures, Renaissance and early twentieth-century modality, eighteenth- and nineteenth-century voice leading schemas, and Baroque and Classical descending-fifth progressions. Also included as an appendix is a list of possible note errors in the published scores of To You, Three and One, and Cherry Juice.
Date: May 2015
Creator: Rogers, Michael A
Partner: UNT Libraries

Plasma Interactions on Organosilicate Glass Dielectric Films and Emerging Amorphous Materials- Approach to Pore Sealing and Chemical Modifications

Description: In-situ x-ray photoemission (XPS) and ex-situ FTIR studies of nanoporous organosilicate glass (OSG) films point to the separate roles of radicals vs. VUV photons in the carbon abstraction. The studies indicate that reaction with O2 in presence of VUV photons (~123 nm) result in significant carbon abstraction within the bulk and that the kinetics of this process is diffusion-limited. In contrast, OSG exposed to atomic O (no VUV) results in Si-C bond scission and Si-O bond formation, but this process is self-limiting after formation of ~1 nm thick SiO2 surface layer that inhibits further diffusion. Therefore, the diffusion-dominated kinetics of carbon abstraction observed for OSG exposed to O2 plasma is definitively attributed to the diffusion of O2 down OSG nanopores, reacting at photo-activated sites, rather than to the diffusion of atomic O. Pretreatment of OSG by 900 eV Ar+ ion bombardment also results in formation of 1 nm thick SiO2-like surface overlayer that inhibits O2 diffusion, inhibiting VUV+O2 and O2 plasma-induced reactions, and that the effectiveness of this treatment increases with ion kinetic energy. On the contrary, organosilicate glass (OSG) films with backbone carbon (-Si-R-Si-) exhibit significantly enhanced resistance to carbon loss upon exposure to O2 plasma, radicals and VUV+O2 compared to films with terminal methyl groups (Si-CH3). Films incorporating backbone carbon chains (-Si-R-Si-) were deposited from 1,2 bis (triethoxysilyl) ethane (BTESE) precursor by ebeam or plasma cross-linking. The radical effects on BTESE film indicates negligible carbon loss or Si oxidation, combined with C-O bond formation, under conditions where OSG films with terminal methyl groups exhibit > 80% carbon loss within the surface region of the film. C-O bond formation is never observed for terminal CH3 groups. Further, backbone carbon (-Si-R-Si-) films exposed to VUV+O2 exhibit self-limiting, minimal net carbon loss. This indicates that plasma-induced Si-C bond rupture still occurs ...
Date: May 2015
Creator: Kazi, Haseeb
Partner: UNT Libraries

Forward Genetic Characterization of Medicago truncatula Tnt1 Insertion Mutants Defective in Nodule Development and Symbiotic Nitrogen Fixation

Description: Legumes are unique plants because they form special structures “nodules”, via symbiotic relationships with rhizobial bacteria present in the soil. Once rhizobia mature inside nodules, they fix atmospheric nitrogen providing a source of bioavailable nitrogen to the plant. To discover novel genetic components involved in the legume-rhizobia symbiosis by using forward genetic screening, we have isolated Medicago truncatula Tnt1 insertion mutants in the R108 ecotype, which are defective in nodule development and symbiotic nitrogen fixation in response to Sinorhizobium meliloti. Out of three mutants NF11044, NF11217 and NF8324, one of the mutants showed brown nodules and Fix- phenotype that is defective in symbiotic nitrogen fixation. The other two mutants showed white nodules and Fix- phenotype, also indicator of defects in symbiotic nitrogen fixation. To identify the underlying mutation causing the phenotype, we have developed molecular genetic markers by obtaining genomic sequences flanking the Tnt1 insertions by TAIL-PCR and Illumina sequencing. To carry out co-segregation analysis, back-crossed BC1F2 segregating populations were obtained. These are being phenotyped, genotyped and analyzed for co-segregation of the phenotype with the Tnt1 genetic markers. Back-crossing also has the effect of reducing the Tnt1 insertions, which are not linked to the nodulation defective phenotypes. Out of the three mutants, NF8324 harbors exactly the same insertion as in the rsd-1 Tnt1 mutant NF11265. The defect in NF11217 is caused by a Tnt1 insertion in the previously described PLC gene; the site of this insertion is close to that found in a different mutant, NF0217. For mutant NF11044, we developed linkage markers that place the defective locus on chromosome 7. To further characterize co-segregation in NF11044, a mapping population has been created by crossing the mutant with other ecotypes: A17 and A20. We tested mutants and wild type plants with linkage marker A20 X NF11044 BC1F2 that segregates 3:1(wild ...
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Date: May 2015
Creator: Kadel, Khem L.
Partner: UNT Libraries

A Case Study of an Urban Charter School’s Journey of School Improvement: Organizational Theory, Institutional Learning and School Reform

Description: The problem for this study was the need to increase and maintain in student achievement in charter schools. The purpose of this single-case study was to discover how an inner city charter school with a high percentage of at-risk students increased overall student achievement and attained acceptable performance status when faced simultaneously with administrative challenges and increases in state and federal standards. The participants for the single-case study included the school district’s superintendent, the high school principal, the dean of students, four faculty of the district, and one outside consultant appointed to work with the district by the state of Texas. The sampling for this study allowed for the opportunity to study in greater depth the choice of reform strategies and organizational structure designed to result in increased student achievement and student success over the course of two years. Since this was a single-case study of one charter school district, participants were referenced by the role in which they served. All district, campus, and participant names remained anonymous. The results showed the increased student achievement was made possible by several reform strategies and best practices. The primary reform strategies and best practices that had the greatest impact were consistent campus leadership and parent and community involvement with the campus. Mission and focus were secondary strategies that contributed to increasing teacher effectiveness and student achievement. All of the interviewees stated their work was “all about the kids” to support the theme of the common mission and focus the campus and district.
Date: May 2015
Creator: Subjinski, Amanda
Partner: UNT Libraries

Manipulations of Sucrose/Proton Symporters and Proton-pumping Pyrophosphatase Lead to Enhanced Phloem Transport But Have Contrasting Effects on Plant Biomass

Description: Delivery of photoassimilate, mainly sucrose (Suc) from photoautotrophic source leaves provides the substrate for the growth and maintenance of sink tissues such as roots, storage tissues, flowers and fruits, juvenile organs, and seeds. Phloem loading is the energized process of accumulating solute in the sieve element/companion cell complex of source leaf phloem to generate the hydrostatic pressure that drives long-distance transport. In many plants this is catalyzed by Suc/Proton (H+) symporters (SUTs) which are energized by the proton motive force (PMF). Overexpression of SUTs was tested as means to enhance phloem transport and plant productivity. Phloem specific overexpression of AtSUC2 in wild type (WT) tobacco resulted in enhanced Suc loading and transport, but against the hypothesis, plants were stunted and accumulated carbohydrates in the leaves, possibly due to lack of sufficient energy to support enhanced phloem transport. The energy for SUT mediated phloem loading is provided from the PMF, which is ultimately supplied by the oxidation of a small proportion of the loaded photoassimilates. It was previously shown that inorganic pyrophosphate (PPi) is necessary for this oxidation and overexpressing a proton-pumping pyrophosphatase (AVP1) enhanced both shoot and root growth, and augmented several energized processes like nutrient acquisition and stress responses. We propose that AVP1 localizes to the PM of phloem cells and uses PMF to synthesize PPi rather than hydrolyze it, and in doing so, maintains PPi levels for efficient Suc oxidation and ATP production. Enhanced ATP production in turn strengthens the PMF via plasma membrane (PM) ATPase, increasing phloem energization and phloem transport. Phloem-specific and constitutive AVP1 overexpressing lines showed increased growth and more efficiently moved carbohydrates to sink organs compared to WT. This suggested changes in metabolic flux but diagnostic metabolites of central metabolism did not show changes in steady state levels. This research focuses on fundamental aspects ...
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Date: May 2015
Creator: Khadilkar, Aswad S
Partner: UNT Libraries

A Training Package for Parents and their Toddlers with Autism: Observed Changes in Parent Teaching Episodes, Child Turn Taking and Social Attending, and Parent-Child Engagement

Description: Research has shown that parents of children with autism report higher stress than parents of children with other developmental disabilities. It has been suggested that parent training programs, specifically naturalistic social-communication training, can reduce parental stress and enhance the quality of the parent-child relationship. Although the development of a multilevel assessment has been suggested, much of the research in this area has relied on measures of parent implementation fidelity and specific child target skills such as vocal communication, eye contact, and joint attention. Few have directly measured the parent-child interaction. The purpose of the current study is to examine the effects of an in-home parent training package for toddlers with autism on parent-child social interactions. Within this package, parents are taught to attend to contextual variables, to arrange the environment to set the occasion for child responding, to respond immediately to targeted child approximations, and to respond in ways that are mutually reinforcing, social, and fun. Data were collected during 5-min video-taped assessments, on the number of parent teaching episodes, child target skills (turn taking and social attending), engagement, and synchronous engagement. Results were evaluated in a multiple baseline design across two parent-child dyads and indicated increases in all measures. This study contributes to the current discussion on toddler parent-training programs and extends it in a way that highlights the benefits of using a multi-level assessment to measure the parent-child interaction.
Date: May 2015
Creator: Hunt, Nina Marie
Partner: UNT Libraries

What Did the Client Say? Auditor Memory of a Client Inquiry: a Study of Encoding Style and Note Taking

Description: Client inquiry is a fundamental procedure for gathering audit evidence. Since inquiries are not audio- or video-recorded in practice, auditor memory is vital to the accuracy of evidence gathered in this manner. Due to the potential for error during memory encoding and retrieval, the effect of memory on judgment, and the cognitive complexity of conducting a face-to-face inquiry, examining factors affecting auditor memory of client inquiries is important. In this dissertation, I examine two factors likely to affect auditor memory of a client inquiry. First, encoding style is a low-level cognitive function representing how much stimuli an individual perceives before applying prior knowledge (schemata) to assist with encoding to long-term memory, affecting information noticed and remembered. Differences in auditors’ encoding style may explain variance in memory accuracy of evidence gathered from a client inquiry. Second, audit professionals often make hand-written or typed notes during client inquiries, and subsequently review the notes, which may affect memory. To address these issues, I first gather interview evidence from six professional auditors to determine how practicing auditors plan, prepare for, conduct, and document evidence from client inquiries. I then develop and execute a video-based experiment with 33 senior auditor participants, 23 masters-level accounting students, and 47 undergraduate-level accounting students to investigate whether encoding style and note taking affect auditor memory accuracy of, and audit judgments resulting from, a client inquiry. I find multiple significant results. First, I find that encoding style affects memory accuracy such that auditors quickly utilizing prior knowledge during an inquiry results in greater memory accuracy than auditors slowly utilizing prior knowledge. This finding suggests that quickly utilizing prior knowledge helps auditors to manage the cognitive complexity of a client inquiry. Second, I find that participants who take notes during an inquiry, and subsequently review his or her notes taken, have ...
Date: May 2015
Creator: Vinson, Jeremy M.
Partner: UNT Libraries

Adult Attachment, Acculturation, and Help-seeking Attitudes of Latino College Students

Description: Based on theoretical reasoning and empirical evidence, the present study examined the unique and shared effects of attachment anxiety, attachment avoidance, and acculturation on attitudes toward seeking professional help among Latino college students. The research participants included 149 bilingual Latino college students from a large, public southwestern university. Results of a multiple regression analysis indicated that attachment avoidance was positively associated with both the recognition of need for psychological help and stigma of seeking professional help. Acculturation to American society was found to be statistically insignificant in predicting help-seeking attitudes in this sample of the population. Findings from exploratory questions suggested that Latino individuals would most likely seek help from parents, close friends, and then professionals. This study suggested that Latino individuals with high attachment avoidance acknowledge the potential benefit of professional help-seeking but distrust the process of approaching others for help. Limitations, implications, and future research directions will be discussed.
Date: May 2015
Creator: Zamudio, Gabriel
Partner: UNT Libraries

La Búsqueda de la Identidad Femenina en las Novelas de Dos Autoras Mexicanas

Description: The novel is one means by which writers can provide examples of the possibilities for women in patriarchal societies to seek greater independence. Sabina Berman (1955- ) and Silvia Molina (1946- ) are modern day Mexican novelists whose writings support the betterment of the female condition in this Latin American society. This study focuses on these two authors and describes and analyzes several of their female protagonists who can be characterized as being in search of their self-identity and self-realization. The novels of interest are La Bobe (2006) and La Mujer que Buceó Dentro del Corazón del Mundo (2010) by Sabina Berman and La Mañana Debe Seguir Gris (1977) and El Amor Que Me Juraste (1998) by Silvia Molina. The theoretical framework used to analyze these novels is based on The Second Sex by Simone de Beauvoir and on the writings of the Mexican author Rosario Castellanos. These novels provide examples of how women can challenge patriarchal social norms in order to seek their identity as an individual and their self-realization. However, to do this, women must be willing to accept the risks and costs that may accompany this self-searching. By seeking identity women can satisfy their longings and desires, but at the same time this may also produce undesired results. Nevertheless, these novels show that women have the ability to seek their personal identity if they take the initiative to do so.
Date: May 2015
Creator: Shrefler, Carmen Lara
Partner: UNT Libraries

Ideal Learning Spaces: the Student Perspective

Description: Classrooms, libraries, student unions, and university campuses shape students’ learning experiences. These physical learning spaces set the stage for college student engagement and academic performance. Most of the research about the role of physical spaces in learning lacks the student perspective. The goal of this study was to offer a student-centered vision of ideal learning spaces. Students are the learners for whom learning spaces are designed, and this thesis examines the way students of one summer class at Oklahoma Baptist University conceptualized and interacted with their learning spaces. Data collection included surveys of the students, a focus group with members of the class, participant observation in the classroom, and interviews with students and the professor. Students viewed physical spaces as the backdrop for human action and chose spaces that supported their learning styles and goals. Students described supportive spaces as warm, purposefully crafted spaces, and full of other people who were seriously pursuing the same goals. This thesis explores the ways students conceptualized and interacted with learning spaces as a network of support for their learning and provides recommendations for the design of learning spaces that facilitate this support.
Date: May 2015
Creator: Sidler, Elizabeth D.
Partner: UNT Libraries

Zooarchaeology and Biogeography of Freshwater Mussels in the Leon River During the Late Holocene

Description: The Leon River, a small-medium river in central Texas, is highly impacted by multiple impoundments, enrichment from agricultural runoff, and decreased dissolved oxygen levels. This degraded river contains sixteen unionid species, two of which are both endemic to the region and candidates for the federal endangered species listing (Quadrula houstonensis and Truncilla macrodon). While there is a short historical record for this river basin and a recent modern survey completed in 2011, zooarchaeological data adds evidence for conservation efforts by increasing the time depth of data available and providing another conservation baseline. Zooarchaeological data for the Leon River is available from the two Late Holocene archaeological sites: 41HM61 and the Belton Lake Assemblages. Data generated from these assemblages describe the prehistoric freshwater mussel community of the Leon River in terms of taxonomic composition and structure. By comparing this zooarchaeological data to the data generated by the longitudinal modern survey of the Leon River, long term changes within the freshwater mussel community can be detected. A conceptual model is constructed to evaluate how robusticity, identifiability, and life history ecology affect unionid taxonomic abundances in zooarchaeological data. This conceptual model functions as an interpretive tool for zooarchaeologists to evaluate forms of equifinality in zooarchaeological assemblages. This thesis determines differences between the late Holocene and modern freshwater community of the Leon River, explores how different alternative mechanisms influence zooarchaeological data, and exemplifies of how zooarchaeological data can be used for conservation biology.
Date: May 2015
Creator: Popejoy, Traci Glyn
Partner: UNT Libraries

Applications of Single Reference Methods to Multi-Reference Problems

Description: Density functional theory is an efficient and useful method of solving single-reference computational chemistry problems, however it struggles with multi-reference systems. Modifications have been developed in order to improve the capabilities of density functional theory. In this work, density functional theory has been successfully applied to solve multi-reference systems with large amounts of non-dynamical correlation by use of modifications. It has also been successfully applied for geometry optimizations for lanthanide trifluorides.
Date: May 2015
Creator: Jeffrey, Chris C.
Partner: UNT Libraries

Investigation on Segmentation, Recognition and 3D Reconstruction of Objects Based on LiDAR Data Or MRI

Description: Segmentation, recognition and 3D reconstruction of objects have been cutting-edge research topics, which have many applications ranging from environmental and medical to geographical applications as well as intelligent transportation. In this dissertation, I focus on the study of segmentation, recognition and 3D reconstruction of objects using LiDAR data/MRI. Three main works are that (I). Feature extraction algorithm based on sparse LiDAR data. A novel method has been proposed for feature extraction from sparse LiDAR data. The algorithm and the related principles have been described. Also, I have tested and discussed the choices and roles of parameters. By using correlation of neighboring points directly, statistic distribution of normal vectors at each point has been effectively used to determine the category of the selected point. (II). Segmentation and 3D reconstruction of objects based on LiDAR/MRI. The proposed method includes that the 3D LiDAR data are layered, that different categories are segmented, and that 3D canopy surfaces of individual tree crowns and clusters of trees are reconstructed from LiDAR point data based on a region active contour model. The proposed method allows for delineations of 3D forest canopy naturally from the contours of raw LiDAR point clouds. The proposed model is suitable not only for a series of ideal cone shapes, but also for other kinds of 3D shapes as well as other kinds dataset such as MRI. (III). Novel algorithms for recognition of objects based on LiDAR/MRI. Aimed to the sparse LiDAR data, the feature extraction algorithm has been proposed and applied to classify the building and trees. More importantly, the novel algorithms based on level set methods have been provided and employed to recognize not only the buildings and trees, the different trees (e.g. Oak trees and Douglas firs), but also the subthalamus nuclei (STNs). By using the novel algorithms based ...
Date: May 2015
Creator: Tang, Shijun
Partner: UNT Libraries

Pastoral Livelihoods and Household Water Management in the Central Argentine Andes

Description: Pastoralists tend to occupy highlands and drylands lands with uncertain climates and are experienced at coping with climatic variability and drought. Increasingly, however, the speed with which climate patterns are changing has become an issue of concern. This study examines household water management strategies of pastoralists in western Argentina. In this semi-arid region, pastoralists rely primarily on streams and springs fed by snow and glacier melt from the Andes, and have developed various strategies to meet their water needs. They also deal with myriad challenges posed by climate, economic, and socio-cultural change and work vigorously to maintain their herds – a combination of cattle, goats, and sheep – in this water scarce region. The goal of this study is to understand: 1) different household water management strategies; 2) the ways pastoral livelihoods are changing in response to changes in water supply; and 3) the socio-economic changes that affect pastoral livelihoods. Information from interviews, household surveys, and participant observations reveals that climate fluctuation impacts water supplies and use, herd size, and expenses made on tanks, technology, and infrastructure for the storage and transport of water, food for animals, and subsistence crops. Understanding the micro-scale, water practices of pastoral households provides insight into the ways rural populations in semi-arid and arid environments respond to changes in climate and meet their water needs. Moreover, these findings can contribute to scholarship on traditional and local knowledge and resource management systems, and may potentially inspire the development of adaptive management solutions.
Date: May 2015
Creator: Parker, Julie
Partner: UNT Libraries

An Application of Marxian and Weberian Theories of Capitalism: the Emergence of Big Businesses in the United States, 1861 to 1890

Description: This study was an examination of businesses that became big businesses in the United States during the time period between the years of 1861 and 1890, a period of time frequently referred to as the “big business era.” The purpose of the study was to identify actions taken by businesses that enabled them to become and remain big businesses. A secondary purpose of the study was to show that these actions were explained by theories of Karl Marx and Max Weber. The results of the study showed that businesses which took specific actions were able to become and remain big businesses and these actions were explained by the theories of Marx and Weber. The results of the study demonstrate the ability of classical sociological theory to explain macro-level social change.
Date: May 2015
Creator: Magness, Penny J.
Partner: UNT Libraries

Space and Spectrum Engineered High Frequency Components and Circuits

Description: With the increasing demand on wireless and portable devices, the radio frequency front end blocks are required to feature properties such as wideband, high frequency, multiple operating frequencies, low cost and compact size. However, the current radio frequency system blocks are designed by combining several individual frequency band blocks into one functional block, which increase the cost and size of devices. To address these issues, it is important to develop novel approaches to further advance the current design methodologies in both space and spectrum domains. In recent years, the concept of artificial materials has been proposed and studied intensively in RF/Microwave, Terahertz, and optical frequency range. It is a combination of conventional materials such as air, wood, metal and plastic. It can achieve the material properties that have not been found in nature. Therefore, the artificial material (i.e. meta-materials) provides design freedoms to control both the spectrum performance and geometrical structures of radio frequency front end blocks and other high frequency systems. In this dissertation, several artificial materials are proposed and designed by different methods, and their applications to different high frequency components and circuits are studied. First, quasi-conformal mapping (QCM) method is applied to design plasmonic wave-adapters and couplers working at the optical frequency range. Second, inverse QCM method is proposed to implement flattened Luneburg lens antennas and parabolic antennas in the microwave range. Third, a dual-band compact directional coupler is realized by applying artificial transmission lines. In addition, a fully symmetrical coupler with artificial lumped element structure is also implemented. Finally, a tunable on-chip inductor, compact CMOS transmission lines, and metamaterial-based interconnects are proposed using artificial metal structures. All the proposed designs are simulated in full-wave 3D electromagnetic solvers, and the measurement results agree well with the simulation results. These artificial material-based novel design methodologies pave the way ...
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Date: May 2015
Creator: Arigong, Bayaner
Partner: UNT Libraries

Stress Response by Alternative σ-factor, RpoH, and Analysis of Posttranslational Modification of the Heat Shock Protein, Dnak, in Escherichia coli

Description: Bacteria have developed specialized responses that involve the expression of particular genes present in a given regulon. Sigma factors provide regulatory mechanisms to respond to stress by acting as transcriptional initiation factors. This work focuses on σ32 during oxidative stress in Escherichia coli. The differential response of key heat shock (HS) genes was investigated during HS and oxidative stress using qPCR techniques. While groEL and dnaJ experienced increases in transcriptional response to H2O2 (10 mM), HS (42°C), and paraquat (50 mM) exposure, the abundance of dnaK over the co-chaperones was apparent. It was hypothesized that DnaK undergoes oxidative modification by reactive carbonyls at its Lys-rich C-terminus, accounting for the differential response during oxidative stress. A σ32-mediated β-galactosidase reporter was devised to detect the activity of wild-type DnaK and DnaKV634X modified to lack the Lys-rich C-terminus. Under unstressed conditions and HS, σ32 was bound at the same rate in both strains. When subjected to H2O2, the WT DnaK strain produced significantly higher β-galactosidase than DnaKV634X (one-tailed Student’s t test p=0.000002, α=0.05) and approached the same level of output as the lacZ positive control. The β-galactosidase assay indicates that DnaK undergoes Lys modification in the WT strain, preventing the protein from binding σ32, increasing the activity of σ32, and resulting in higher β-galactosidase activity than the DnaKV634X strain. In the DnaKV634X strain DnaK continues to bind σ32 so that σ32 could not promote the production of β-galactosidase. These findings demonstrate how DnaK is oxidatively modified, hindering the interaction with σ32 in manner distinct from HS.
Date: May 2015
Creator: Martinez, Sarah N.
Partner: UNT Libraries

A Restorative Environmental Justice for the Prison Industrial Complex: a Transformative Feminist Theory of Justice

Description: This dissertation provides a feminist restorative model of environmental justice that addresses the injustices found within UNICOR’s e-waste recycling operations. A feminist restorative environmental justice challenges the presupposition that grassroots efforts, law and policy, medical and scientific research, and theoretical pursuits (alone or in conjunction) are sufficient to address the emotional and relational harm of environmental injustices. To eliminate environmental harms, this model uses collaborative dialogue for interested parties to prevent environmental harm. To encourage participation, a feminist restorative model accepts many forms of knowledge and truth as ‘legitimate’ and offers an opportunity for women to share how their personal experiences of love, violence, and caring differ from men and other women and connect to larger social practices. This method of environmental justice offers opportunities for repair, reparation and reintegration that can transform perspectives on criminality, dangerous practices and structures in the PIC, and all persons who share in a restorative encounter.
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Date: May 2015
Creator: Conrad, Sarah M.
Partner: UNT Libraries

Examining Self-efficacy in Community College Adjunct Faculty

Description: Though professional development interventions are widespread in higher education, administrators often do not formally assess their effectiveness, particularly in relation to teacher self-efficacy. The purposes of this study were to determine if any statistically significant difference existed between the self-efficacy scores of adjunct faculty participants in a community college’s professional development program and nonparticipants and to identify the variables with a statistically significant relationship with self-efficacy. A modified version of the Teachers’ Sense of Efficacy Scale (TSES) was administered to 21 adjunct faculty participants in Lone Star College’s Adjunct Certification Program (ACP) and 312 adjunct faculty not currently participating in the program. A demographic questionnaire development by the researcher was also administered. Independent variables of the demographic questionnaire included gender, ethnicity, age, K-12 teaching experience, highest degree earned, subject taught, years of college teaching experience, and number of courses taught each semester. Paired t-test results indicated statistically significant differences in Efficacy in Instructional Strategies for adjunct participants in the ACP program. No significant differences were found for Efficacy in Student Engagement and Efficacy in Classroom Management. Multiple regression analyses indicated that gender has a statistically significant relationship to Efficacy Instructional Strategies. A statistically significant relationship was found for race for Efficacy in Classroom Management. Finally, analysis also indicated a positive relationship between race and gender for Efficacy in Student Engagement. No other statistically significant relationships were found across the other demographic variables. Findings of this study revealed that the ACP increased teacher self-efficacy across two of the three dimensions of the TSES indicating that the professional development intervention had a positive effect on the efficacy of its participants. The present study contributes to the research on teacher self-efficacy, adjunct faculty and professional development interventions.
Date: May 2015
Creator: Weisel, Jessica W.
Partner: UNT Libraries

The Mechanisms of Human Glutathione Synthetase and Related Non-Enyzmatic Catalysis

Description: Human glutathione synthetase (hGS) is a homodimeric enzymes that catalyzes the second step in the biological synthesis of glutathione, a critical cellular antioxidant. The enzyme exhibits negative cooperativity towards the γ-glutamylcysteine (γ-GC) substrate. In this type of allosteric regulation, the binding of γ-GC at one active site significantly reduces substrate affinity at a second active site over 40 Å away. The presented work explores protein-protein interactions, substrate binding, and allosteric communication through investigation of three regions of hGS: the dimer interface, the S-loop, and the E-loop. Strong electrostatic interactions across the dimer interface of hGS maintain the appropriate tertiary and quaternary enzymatic structure needed for activity. The S-loop and E-loop of hGS form walls of the active site near γ-GC, with some residues serving to bind and position the negatively cooperative substrate. These strong interactions in the active site serve as a trigger for allosteric communication, which then passes through hydrophobic interactions at the interface. A comprehensive computational and experimental approach relates hGS structure with activity and regulation. ATP-grasp enzymes, including hGS, utilize ATP in the nucleophilic attack of a carboxylic acid in a reaction thought to proceed through the formation of an acylphosphate intermediate. Small metal cations are known to chelate the terminal phosphates of actives site ATP, yet the role of these atoms remains unclear. In the presented work, a computational metal substitution study establishes the role these divalent cations in the catalysis of peptide bonds. The simple model is used to determine the impact of metal cations on the thermodynamics and kinetics, an important stepping stone in understanding the importance of metal cations in larger biological systems.
Date: May 2015
Creator: Ingle, Brandall L.
Partner: UNT Libraries

Effects of Auditor-provided Tax Services on Book-tax Differences and Investors’ Mispricing of Book-tax Differences

Description: In this study, I investigate the effect of auditor-provided tax services (ATS) on firms’ levels of book-tax differences and investors’ mispricing of book-tax differences. The joint provision of audit and tax services has been a controversial issue among regulators and academic researchers. Evidence on whether ATS improve or impair the overall accounting quality is inconclusive as a result of the specific testing circumstances involved in different studies. Book-tax differences capture managers’ earnings management and/or tax avoidance intended to maximize reported financial income and to minimize tax expense. Therefore, my first research question investigates whether ATS improve or impair audit quality by examining the relation between ATS and firms’ levels of book-tax differences. My results show that ATS are negatively related to book-tax differences, suggesting that ATS improve the overall audit quality and reduce aggressive financial and/or tax reporting. My second research question examines whether the improved earnings quality for firms acquiring ATS leads to reduced mispricing of book-tax differences among investors. Recent studies document that despite the rich information about firms’ future earnings contained in book-tax differences, investors process such information inefficiently, leading to systematic pricing errors among firms with large book-tax differences. My empirical evidence indicates that ATS mitigate such mispricing, with pricing errors being lower among firms acquiring ATS compared with firms without ATS. Collectively, these results support the notion that ATS improve audit quality through knowledge spillover. Moreover, the improved earnings quality among firms acquiring ATS in turn helps reduce investors’ mispricing of book-tax differences.
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Date: May 2015
Creator: Luo, Bing
Partner: UNT Libraries

An Analysis of Market Efficiency for Exchange-traded Foreign Exchange Options on an Intraday Basis

Description: This study examines the comparative magnitude of disturbances in intraday data for exchange traded foreign exchange (FX) options. An in-depth time series analysis on the frequency and extent of discrepancies in the disturbances is conducted. The purpose of this study is twofold. First, using intraday data and trading volume, this study attempts to determine whether both put-call parity and lower boundary conditions consistently hold for exchange traded options written on U.S. dollar denominated options on the Euro trading on the Philadelphia Stock Exchange (PHLX). Second, this study attempts to investigate the magnitude of any discrepancies that may exist due to a temporary cessation of either put-call parity or lower boundary conditions. Intraday (tick-by-tick) bid prices, ask prices, and trading volume on U.S. dollar denominated European style call options and put options on the Euro are obtained. Option data is collected through a Structured Query Language (SQL) request from the Bloomberg database. Corresponding tick-by-tick spot rates for the underlying exchange rate are obtained for the same time period. Tick-by-tick 3-month Treasury bill rates are obtained to for use as the relevant risk-free interest rate. The primary data set spans an approximate one month period from 11/1/2011 to 12/6/2011. Call and option pricing data for near-the-money exercise prices are obtained for options expiring in December 2011, January 2012, February 2012, March 2012, June 2012, and September 2012. A total of 7,212 ticks (minutes) are analyzed for the conversion strategy and 7,209 ticks are analyzed for the reversal strategy. The data is structured into an unbalanced panel data set (cross-sectional time series data) using put-call pairs as the cross sectional units and ticks as the time-series unit. To test the efficiency of the foreign exchange options market, lower boundary and put-call parity conditions were tested on tick-by-tick currency option data. Analysis shows that ...
Date: May 2015
Creator: Ren, Peter
Partner: UNT Libraries