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 Collection: UNT Theses and Dissertations
In Vitro Investigations of Antibiotic Influences on Nerve Cell Network Responses to Pharmacological Agents

In Vitro Investigations of Antibiotic Influences on Nerve Cell Network Responses to Pharmacological Agents

Date: December 2014
Creator: Sawant, Meera
Description: Neuronal networks, derived from mouse embryonic frontal cortex (FC) tissue grown on microelectrode arrays, were used to investigate effects of gentamicin pretreatment on pharmacological response to the L-type calcium channel blocker, verapamil. Gentamicin is a broad spectrum antibiotic used to control bacterial contamination in cell culture. The addition of gentamicin directly to medium affects the pharmacological and morphological properties of the cells in culture. A reproducible dose response curve to verapamil from untreated cultures was established and the mean EC50 was calculated to be 1.5 ± 0.5 μM (n=10). 40 μM bicuculline was added to some cell cultures to stabilize activity and verapamil dose response curves were performed in presence of bicuculline, EC50 1.4 ± 0.1 μM (n=9). Statistical analysis showed no significant difference in verapamil EC50s values obtained in presence of bicuculline and hence the data was combined and a standard verapamil EC50 was calculated as 1.4 ± 0.13 μM (n=19). This EC50 was then used to compare verapamil EC50s obtained from neuronal cell cultures with chronic and acute exposures to gentamicin. FC cultures (21- 38 days old) were found to be stable in presence of 2300 μM gentamicin. The recommended concentration of gentamicin for contamination control is 5uL ...
Contributing Partner: UNT Libraries
Electromagnetic Shielding Properties of Iron Oxide Impregnated Kenaf Bast Fiberboard

Electromagnetic Shielding Properties of Iron Oxide Impregnated Kenaf Bast Fiberboard

Date: December 2014
Creator: Ding, Zhiguang
Description: The electromagnetic shielding effectiveness of kenaf bast fiber based composites with different iron oxide impregnation levels was investigated. The kenaf fibers were retted to remove the lignin and extractives from the pores in fibers, and then magnetized. Using the unsaturated polyester and the magnetized fibers, kenaf fiber based composites were manufactured by compression molding process. The transmission energies of the composites were characterized when the composite samples were exposed under the irradiation of electromagnetic (EM) wave with a changing frequency from 9 GHz to 11 GHz. Using the scanning electron microscope (SEM), the iron oxide nanoparticles were observed on the surfaces and inside the micropore structures of single fibers. The SEM images revealed that the composite’s EM shielding effectiveness was increased due to the adhesion of the iron oxide crystals to the kenaf fiber surfaces. As the Fe content increased from 0% to 6.8%, 15.9% and 18.0%, the total surface free energy of kenaf fibers with magnetizing treat increased from 44.77 mJ/m2 to 46.07 mJ/m2, 48.78 mJ/m2 and 53.02 mJ/m2, respectively, while the modulus of elasticity (MOE) reduced from 2,875 MPa to 2,729 MPa, 2,487 MPa and 2,007 MPa, respectively. Meanwhile, the shielding effectiveness was increased from 30-50% to 60-70%, ...
Contributing Partner: UNT Libraries
Comparative Analysis of the Musical Distortion in Kaikhosru Sorabji’s and Vladimir Horowitz’s Piano Paraphrases Based on Bizet’s Opera Carmen

Comparative Analysis of the Musical Distortion in Kaikhosru Sorabji’s and Vladimir Horowitz’s Piano Paraphrases Based on Bizet’s Opera Carmen

Date: December 2014
Creator: Kim, Mi-Jin
Description: This study focuses on a comparative analysis of two piano paraphrases, Pastiche on Habanera from ‘Carmen’ by Kaikhosru Sorabji and Variations on a Theme from Bizet’s ‘Carmen’ by Vladimir Horowitz. These compositions idiomatically distort the original material in a manner that was not explored up to the moment of their respective conception. They expose each composer’s free compositional approach, reflecting musical freedom rooted in the originality of their musical thinking. The aesthetic uniqueness of these two compositions strongly stimulates and justifies academic interest to explore their technical construction, musical differences, and artistic significance. This study proposes to undertake a comparative study of these two compositions, analyzing (1) aspects of the musical character, which are linked with embellishment, or rearrangement of original material, and (2) differences in performance approach based on recorded examples and critical observations by others of the performances of these works by Sorabji and Horowitz.
Contributing Partner: UNT Libraries
The Effects of Model Prompts on Joint Attention Initiations in Children with Autism

The Effects of Model Prompts on Joint Attention Initiations in Children with Autism

Date: December 2014
Creator: James-Kelly, Kimberly L
Description: The general purpose of the current study was to evaluate the effects of minimally intrusive prompting procedures and preferred stimuli on protodeclarative joint attention initiations in children diagnosed with autism spectrum disorder (ASD). Two boys and one girl diagnosed with ASD participated. The experimenter provided attention and social interaction following protodeclarative initiations throughout all phases of the study. During intervention, a model prompt was delivered every 30 s if the participant failed to initiate a bid for joint attention. Results for the first participant show that a model prompt was sufficient to increase the rate of protodeclarative initiations across stimulus sets. Generalization was seen across sets, but not across environments. Subsequently, the model prompt was sufficient to increase the rate of protodeclarative initiations across sets in a second setting (classroom). Results for the second participant are inconclusive. Data collected during the initial baseline condition show that she engaged in an incompatible verbal response across sets. When pictorial stimuli depicting highinterest items and activities were introduced, the rate of protodeclarative initiations increased over time. We then returned to original baseline condition and saw an initial decrease, followed by a steady increase in the rate of protodeclarative initiations. The third participant withdrew ...
Contributing Partner: UNT Libraries
Characterization of Ionic Liquid Solvents Using a Temperature Independent, Ion-specific Abraham Parameter Model

Characterization of Ionic Liquid Solvents Using a Temperature Independent, Ion-specific Abraham Parameter Model

Date: December 2014
Creator: Stephens, Timothy W.
Description: Experimental data for the logarithm of the gas-to-ionic liquid partition coefficient (log K) have been compiled from the published literature for over 40 ionic liquids over a wide temperature range. Temperature independent correlations based on the Gibbs free energy equation utilizing known Abraham solvation model parameters have been derived for the prediction of log K for 12 ionic liquids to within a standard deviation of 0.114 log units over a temperature range of over 60 K. Temperature independent log K correlations have also been derived from correlations of molar enthalpies of solvation and molar entropies of solvation, each within standard deviations of 4.044 kJ mol-1 and 5.338 J mol-1 K-1, respectively. In addition, molar enthalpies of solvation and molar entropies of solvation can be predicted from the Abraham coefficients in the temperature independent log K correlations to within similar standard deviations. Temperature independent, ion specific coefficients have been determined for 26 cations and 15 anions for the prediction of log K over a temperature range of at least 60 K to within a standard deviation of 0.159 log units.
Contributing Partner: UNT Libraries
Charles Wuorinen’s Flute Variations Ii: an Analysis and Performance Guide

Charles Wuorinen’s Flute Variations Ii: an Analysis and Performance Guide

Date: December 2014
Creator: Dewhirst, Kristan K
Description: Charles Wuorinen’s contributions to contemporary music are significant. He has produced more than 260 compositions in a wide array of genres including pieces for orchestra, opera, ballet, chamber ensemble, and soloists. This document serves as an analysis and performance guide for Charles Wuorinen’s work for solo flute, Flute Variations II. Issues of analysis include serial techniques, time-point nesting, and pitch centricity and provide insight into the compositional style of the composer. As this work exhibits techniques borrowed from traditional shakuhachi performance, this document provides a brief history of the shakuhachi and an overview of the shakuhachi techniques utilized in Flute Variations II. The performance guide provides a pedagogical narrative to aid in the synthesis of conceptual ideas with contemporary techniques.
Contributing Partner: UNT Libraries
Electrodeposition of Nickel and Nickel Alloy Coatings with Layered Silicates for Enhanced Corrosion Resistance and Mechanical Properties

Electrodeposition of Nickel and Nickel Alloy Coatings with Layered Silicates for Enhanced Corrosion Resistance and Mechanical Properties

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Date: August 2014
Creator: Tientong, Jeerapan
Description: The new nickel/layered silicate nanocomposites were electrodeposited from different pHs to study the influence on the metal ions/layered silicate plating solution and on the properties of the deposited films. Nickel/layered silicate nanocomposites were fabricated from citrate bath atacidic pHs (1.6−3.0), from Watts’ type solution (pH ~4-5), and from citrate bath at basic pH (~9). Additionally, the new nickel/molybdenum/layered silicate nanocomposites were electrodeposited from citrate bath at pH 9.5. The silicate, montmorillonite (MMT), was exfoliated by stirring in aqueous solution over 24 hours. The plating solutions were analyzed for zeta potential, particle size, viscosity, and conductivity to investigate the effects of the composition at various pHs. The preferred crystalline orientation and the crystalline size of nickel, nickel/layered silicate, nickel/molybdenum, and nickel/molybdenum/layered silicate films were examined by X-ray diffraction. The microstructure of the coatings and the surface roughness was investigated by scanning electron microscopy and atomic force microscopy. Nickel/molybdenum/layered silicate nanocomposites containing low content of layered silicate (1.0 g/L) had increase 32 % hardness and 22 % Young’s modulus values over the pure nickel/molybdenum alloy films. The potentiodynamic polarization and electrochemical impedance measurements showed that the nickel/molybdenum/layered silicate nanocomposite layers have higher corrosion resistance in 3.5% NaCl compared to the pure alloy ...
Contributing Partner: UNT Libraries
An Examination of Text Reflection and Imagery in Zoltán Gárdonyi’s Fünf Lieder Nach Gedichten Von Rainer Maria Rilke

An Examination of Text Reflection and Imagery in Zoltán Gárdonyi’s Fünf Lieder Nach Gedichten Von Rainer Maria Rilke

Date: August 2014
Creator: Beloncik Schantz, Anne
Description: Zoltán Gárdonyi is described as having exemplified “the continuation of the Liszt tradition” in his music; however, since for so much of his compositional life he was forbidden to publish by the Communist government in Hungary due to his connection to the Christian church, he has been largely forgotten. Shortly after the composer’s death in 1986, Gárdonyi’s son, Zsolt (b.1946) began publishing his father’s music in addition to his own. However, the elder Gárdonyi’s works are still not widely known outside Hungary and Germany. Gárdonyi’s ability to support and reflect text musically makes his songs excellent teaching tools and recital repertoire. A characteristic example of this may be found in his Fünf Lieder nach Gedichten von Rainer Maria Rilke. According to his son, Zoltán wrote these songs “in the German romantic tradition (e.g. Brahms) like a mirror for the romantic influenced lyrics.” Examination of the Rilke-Lieder, and of the poems which make up the cycle, demonstrates the composer’s ability to “mirror” text in both general tone and specific idea. Discussion of imagery, textures and sonorities, and elements of harmony, melody and rhythm as they relate to interpretation of the poetry, reveal the depth to which the poetry is embedded in ...
Contributing Partner: UNT Libraries
Cowboys, “Queers,” and Community: the Aids Crisis in Houston and Dallas, 1981-1996

Cowboys, “Queers,” and Community: the Aids Crisis in Houston and Dallas, 1981-1996

Date: August 2014
Creator: Bundschuh, Molly Ellen
Description: This thesis examines the response to the AIDS crisis in Houston and Dallas, two cities in Texas with the most established gay communities highest number of AIDS incidences. Devoting particular attention to the struggles of the Texas’ gay men, this work analyzes the roadblocks to equal and compassionate care for AIDS, including access to affordable treatment, medical insurance, and the closure of the nation’s first AIDS hospital. In addition, this thesis describes the ways in which the peculiar nature of AIDS as an illness transformed the public perception of sickness and infection. This work contributes to the growing study of gay and lesbian history by exploring the transformative effects of AIDS on the gay community in Texas, a location often forgotten within the context of the AIDS epidemic.
Contributing Partner: UNT Libraries
The Measurement of Occupational Identity Among Undergraduate Preservice Music Teachers: a Test Development Study

The Measurement of Occupational Identity Among Undergraduate Preservice Music Teachers: a Test Development Study

Date: August 2014
Creator: Rewolinski, Christine
Description: A large segment of society is either preparing to enter the work force, or is already engaged in some chosen line of work. Preparing to enter the work force takes a considerable amount of time and effort. The decision to follow one career path over countless others may, on the surface, appear to be discretely individual. But when viewed from a sociological perspective, occupational choices are implicitly and explicitly reached through a consensus of contributing factors. Consequently, an occupational identity is not how an individual describes a personal work-related self, but is rather dialectic. It is the merging, albeit, negotiation of viewpoints which causes persons to view themselves in relationship with how others think of them. It is expected that students newly enrolled in music education degree programs will, with time, replace erroneous lay conceptions of music teaching with those presented in curricula and espoused by significant role models. However, the professional socialization process, characteristic of music education degree programs, has not always been successful in transforming students’ personal perspectives of music teaching. This transformation process is critical toward the development of occupational identities that are congruent with school music teaching positions. There has been an established line of research ...
Contributing Partner: UNT Libraries
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