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Treatment Outcomes Related to EEG-Biofeedback for Chemical Dependency: Changes in MMPI-2™ (University of Minnesota) Personality Measures and Long Term Abstinence Rates

Description: Peniston and Kulkosky (1989, 1990) demonstrated the effectiveness of alpha-theta EEG-Biofeedback (EEG-BFB) in treating inpatient alcoholics noting significant improvements in depression, psychopathology, serum β-endorphin levels, and abstinence rates. The present study is an extension of a previously unpublished replication of the Peniston EEG-BFB protocol with 20 chemically dependent outpatients (Bodenhamer-Davis, Callaway, & DeBeus, 2002). Fifteen subjects were "high risk for re-arrest" probationers. Data for the EEG-BFB group was collected from archival records. Subjects completed an average of 39 sessions (SD = 6.096), with 33 of those being EEG-BFB. Pre/post-treatment MMPI-2s™ (University of Minnesota) were collected and follow-up (4-11 years) data obtained (abstinence rates, re-arrests in some cases). Treatment effects were evaluated by comparing assessment data (pre/post) and documenting abstinence rates. Post-treatment MMPI-2 results were within normal limits, with several scales significantly reduced from baseline suggesting less psychopathology. Results were then compared to 20 subjects receiving standard addiction treatment (OT-CD group), but not EEG-BFB. OT-CD subjects completed a 2-week inpatient program followed by 18 outpatient sessions. Pre/post assessment and follow-up data was collected on the OT-CD group. The OT-CD group's post-assessment results showed three elevations (MMPI-2 scales 4/6/8), suggestive of characteriological problems. Post-MMPI-2 results of the two groups were compared via ANCOVAs. Findings indicated no significant differences between groups on targeted scales; however, there was a trend for the EEG-BFB group to have lower scores. Follow-up data was obtained on 13 EEG-BFB subjects. Results indicated 92% (n = 12) were sober, with 8% (n = 1) claiming significantly reduced alcohol intake. Probationer re-arrest and revocation rates were collected on the subset of probationers (n = 14 out of 15). The majority of the probationers (79%, n = 11) had not been re-arrested nor had their probation been revoked. Short-term follow-up information (35-131 days post-assessment), available at the time of writing, for ...
Date: May 2005
Creator: Callaway, Tonya Gayle
Partner: UNT Libraries

Connecting Ireland and America: Early English Colonial Theory 1560-1620

Description: This work demonstrates the connections that exist in rhetoric and planning between the Irish plantation projects in the Ards, Munster , Ulster and the Jamestown colony in Virginia . The planners of these projects focused on the creation of internal stability rather than the mission to 'civilize' the natives. The continuity between these projects is examined on several points: the rhetoric the English used to describe the native peoples and the lands to be colonized, who initiated each project, funding and financial terms, the manner of establishing title, the manner of granting the lands to settlers, and the status the natives were expected to hold in the plantation. Comparison of these points highlights the early English colonial idea and the variance between rhetoric and planning.
Date: May 2005
Creator: Nelson, Robert Nicholas
Partner: UNT Libraries

Higher Education and Entrepreneurship: The Relation between College Educational Background and Small Business Success in Texas

Description: This study examined the relationship between success of small businesses and the educational backgrounds of their owners. A survey composed of questions concerning demographics, educational backgrounds, and business success was mailed to 1100 businesses in Dallas, Denton, and Tarrant counties in Texas. There were 228 usable responses which were analyzed by using the Statistical Package of Social Sciences (SPSS12). Data were sorted so that educational level, sales volume, number of employees, and longevity, were identified on a 5-point ordinal scale. Educational major was identified on a 5-point nominal scale. Pearson's correlation was used to determine whether relationships existed between founders' educational background and small business success. Spearman's correlation was used to determine the direction and strength of the relationships. Then educational level and major were combined with age, gender, ethnicity, and industry, to determine the relationships between founders' educational background, and business success. For this purpose a canonical correlation was used. Five opinion questions concerned influence of college education on business success among college graduates and non-college graduates were identified on a 5-point Likert scale and tested using one-way ANOVA, and independent sample t-test. When educational level and major were the only predictors of business success, a statistically significant relationship was found between years of formal education, and sales volume. When educational level and major were combined with age, gender, ethnicity, and industry, a statistically significant relationship was found between founders' educational level and age, and business success. A statistically significant and negative relationship was found between founders' educational major and industry, and business success. All opinion questions revealed statistically significant relationships between owner's college education and business success. These relationships indicate the ability for the owner to learn, adapt and maintain a successful business. The influence of a college education on small business success was noticeable and reflects the ...
Date: May 2005
Creator: Al-Zubeidi, Mohammad
Partner: UNT Libraries

A survey study of entry transition practices used by teachers of infants and toddlers.

Description: This study identified transition practices used by teachers and/or primary caregivers of infants and toddlers when entering child care programs across Dallas , TX . Participants completed the Program Entry Transition Practices Survey regarding their use of transition practices in fall 2003 and perceived barriers to entry transition practices. Results show frequency tallies, percentages of use for each transition practice, and the mean number of practices used for the entire sample and with the sample split according to participants from profit and non-profit programs. Results were also organized into four subscales based on the type of practice used. Results supported the hypothesis that teachers and caregivers would report more transition practices occurring after beginning care and directed towards a group than those occurring before beginning care and directed towards an individual. In response to the broader research question regarding barriers: Teachers and caregivers from profit and non-profit centers reported similar barriers to implementing transition practices.
Date: December 2004
Creator: Fernandez, Mary Elizabeth Poteet
Partner: UNT Libraries

Saturation and foaming of thermoplastic nanocomposites using supercritical CO2.

Description: Polystyrene (PS) nanocomposite foams were prepared using supercritical fluid (SCF) CO2 as a solvent and blowing agent. PS was first in-situ polymerized with a range of concentrations of montmorillonite layered silicate (MLS). The polymerized samples were then compression molded into 1 to 2mm thick laminates. The laminates were foamed in a batch supercritical CO2 process at various temperatures and pressures from 60°-85°C and 7.6-12MPa. The resulting foams were analyzed by scanning electron microscopy to determine effect of MLS on cellular morphology. Differential scanning calorimetry was used to determine the impact of nanocomposite microstructure on glass transition of the foamed polymer. X-ray diffraction spectra suggested that the PS/MLS composite had an intercalated structure at both the 1% and 3% mixtures, and that the intercalation may be enhanced by the foaming process.
Date: May 2005
Creator: Strauss, William C.
Partner: UNT Libraries

The stonefly genus Isogenoides Klapálek (Plecoptera: Perlodidae) of North America: Systematics, behavior and ecology.

Description: The stonefly genus Isogenoides is revised following a holomorphological approach utilizing traditional morphology and behavioral lines of evidence. Species keys are provided for all life stages. One species, I. krumholzi (Ricker) is considered a synonym of I. doratus (Frison). Detailed species descriptions are provided for males, females, nymphs and ova. Distributions are updated utilizing all known published accounts and materials examined. The vibrational communication (drumming) behavior is reported for males and all but one species for females. The signals were species-specific and ranged in complexity from ancestral sequenced duets to derived grouped exchanges. I. olivaceus is least specialized, having mostly sequenced duets, and I. zionensis most specialized, displaying ancestral sequenced, derived grouped and complex derived exchanges containing both sequenced and grouped elements. Laboratory egg incubation experiments over a 2-4 year period show that Isogenoides has a great capacity for extended, sometimes-asynchronous diapause and hatching. The eggs of six species were incubated at a single, ca. simulated San Miguel River, Colorado, seasonal temperature regime. Direct hatch within two weeks occurred only for I. zionensis (Leopard Creek, Colorado) with small numbers hatching again after one, two, and four years. Eggs of I. doratus and I. varians hatched after an over summer, 3-5 month diapause, and I. varians again in August the next year. Populations of I. colubrinus, I. elongatus, I. frontalis and San Miguel River, I. zionensis began hatching after a 9-11 month diapause and again during spring-summer temperatures in 2nd through 4th years. I. zionensis in the San Miguel River, Colorado, exhibited a semivoltine life cycle over the two-year study period. Adults emerged in June-July when stream temperature reached ca. 11-17°C. Reared females at Quartz Creek, Pitkin, Colorado, deposited up to three egg batches. Mean fecundity of females was 691 egg/female. Oviposition in the field was observed and described. Nymphal growth ...
Date: May 2005
Creator: Sandberg, John Burton
Partner: UNT Libraries

Chemistry, Detection, and Control of Metals during Silicon Processing

Description: This dissertation focuses on the chemistry, detection, and control of metals and metal contaminants during manufacturing of integrated circuits (ICs) on silicon wafers. Chapter 1 begins with an overview of IC manufacturing, including discussion of the common aqueous cleaning solutions, metallization processes, and analytical techniques that will be investigated in subsequent chapters. Chapter 2 covers initial investigations into the chemistry of the SC2 clean - a mixture of HCl, H2O2, and DI water - especially on the behavior of H2O2 in this solution and the impact of HCl concentration on metal removal from particle addition to silicon oxide surfaces. Chapter 3 includes a more generalized investigation of the chemistry of metal ions in solution and how they react with the silicon oxide surfaces they are brought into contact with, concluding with illumination of the fundamental chemical principles that govern their behavior. Chapter 4 shows how metal contaminants behave on silicon wafers when subjected to the high temperature (≥ 800 °C) thermal cycles that are encountered in IC manufacturing. It demonstrates that knowledge of some fundamental thermodynamic properties of the metals allow accurate prediction of what will happen to a metal during these processes. Chapter 5 covers a very different but related aspect of metal contamination control, which is the effectiveness of metal diffusion barriers (e.g. Ru) in holding a metal of interest, (e.g. Cu), where it is wanted while preventing it from migrating to places where it is not wanted on the silicon wafer. Chapter 6 concludes with an overview of the general chemical principles that have been found to govern the behavior of metals during IC manufacturing processes.
Date: May 2005
Creator: Hurd, Trace Q.
Partner: UNT Libraries

The Constitutionality of Dress Code and Uniform Policies

Description: This dissertation proposes to delineate the criteria for determining the constitutionality of public school dress codes based on an examination of relevant case law. The study addresses the following underlying questions: (1) Do students have a constitutional right to freedom of choice regarding their personal dress and grooming in public schools? (2) If so, what is the origin of the right? (3) What justification does a school district need in order to intrude upon the right? (4) Does the extent to which there is a right, and that it is accorded support by the judiciary, depend on the student's age and grade level? (5) What do state statutes say about dress codes and uniforms? (6) Do state statutes comport with the circuit courts' rulings in the various jurisdictions? The first part of Chapter I examines the purpose of school uniforms as set forth in relevant educational literature and commentary. The second part of the chapter examines empirical evidence on the effects of dress codes and uniforms. Chapter II addresses the first three questions listed above concerning students' right to choice in personal dress, the origins of such a right, and the justification required for a school to intrude upon this right. Chapter III examines dress code rulings from the United States Courts of Appeals in order to ascertain patterns of judicial rationale and determine whether students' rights vary depending on age, grade level, or federal circuit court jurisdiction. Chapter IV examines existing state statutes with regard to dress codes and uniforms. Chapter V utilizes the legal principles that emerge from the research in Chapter III and draws from the survey of state statutes in Chapter IV to make a comparison of state statutes and circuit court rulings in each jurisdiction. If a state statute does not comport with federal law ...
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Date: May 2005
Creator: Stromberger, Joanne
Partner: UNT Libraries

Understanding and preventing police use of excessive force: An analysis of attitudes toward police job satisfaction and human rights laws.

Description: Although governments try to create strict policies and regulations to prevent abuses, use of excessive force is still a problem for almost every country including Turkey. This study is intended to help Turkish National Police administrators to understand and prevent police use of excessive force. Studies on police brutality categorize three factors that explain why police officers use excessive force; these are individual, situational and organizational. In addition to brutality theories, job satisfaction literature is examined in this study to understand the use of excessive force. Job satisfaction is found to be related with burnout, turnover, stress, commitment, and performance. The impact of officers' attitude toward the criminal justice system and/or laws has not been tested widely. Police officers attitudes toward human rights laws are examined in this study to measure its impact on attitude toward use of excessive force. A secondary data collected in Turkey are analyzed by structural equation modeling which provides confirmatory factor analysis, path analysis, and causal relationships between variables. It is found that police officers' attitude toward human rights laws is a significant predictor of their attitudes toward use of excessive force. Job satisfaction and education level are the other significant variables affecting attitude toward use of excessive force. Based on the analyses of findings, educational and policy implications are posed for Turkish police administrators to better understand and prevent police use of excessive force.
Date: December 2009
Creator: Akdogan, Huseyin
Partner: UNT Libraries

Synthesis and Characterization of Platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(dichloride), Platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione(maleonitriledithiolate), and Platinum(II)(4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(4-Methyl-1,2-benzene dithiol)

Description: Substitution of the 1,5-cyclooctadiene (cod) ligand in PtCl2(cod) (1) by the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) yields PtCl2(bpcd) (2). Knoevenagel condensation of 2 with 9-anthracenecarboxaldehyde leads to the functionalization of the bpcd ligand and formation of the corresponding 2-(9-anthracenylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (abpcd) substituted compound PtCl2(abpcd) (3), which is also obtained from the direct reaction of 1 with the abpcd ligand in near quantitative yield. The reaction of 3 with disodium maleonitriledithiolate (Na2mnt) affords the chelating dithiolate compound Pt(mnt)(abpcd) (4). The reaction of PtCl2(bpcd) (2) with 4-methyl-1,2-benzene dithiol under basic conditions affords Pt(tdt)(bpcd) (5). Compounds 2-5 have been fully characterized in solution by IR and NMR spectroscopies (1H and 31P), and their molecular structures established by X-ray crystallography. The electrochemical properties of 2‑5 have examined by cyclic voltammetry, and the nature of the HOMO and LUMO levels in systems 2-4 has been established by MO calculations at the extended Hückel level, the results of which are discussed with respect to electrochemical data and related diphosphine derivatives. In addition the new compounds 2-5 have been isolated by column chromatography and characterized by IR, UV-Vis spectroscopy.
Date: December 2009
Creator: Hunt, Sean W.
Partner: UNT Libraries

An Introduction to the AIDS Quilt Songbook and Its Uncollected Works

Description: The AIDS Quilt Songbook was a musical response to the shame surrounding the outbreak of the HIV virus and was one of the first art song publications to deal with the topic of HIV and AIDS. This DMA thesis documents the significance and history of the AIDS Quilt Songbook, traces the progression of the project up until December 1, 2008, and documents the work, experiences, and words of the composers who have been inspired to contribute to the AIDS Quilt Songbook Project. In 1981, the medical and popular press reported the first cases of a quickly spreading virus among homosexual males. This virus is currently diagnosed as HIV and AIDS. Lack of funding consumed the early years of what grew to become a national pandemic. The artistic community was one of the major catalysts for funding and education. Cleave Jones and other gay rights activists developed the NAMES Project as a memoriam for those lost to the pandemic. The AIDS Quilt Songbook was created to parallel the AIDS Quilt as "a never-ending work whose meaning and spirit is renewed and redefined with every addition." This concept of additions has continued the expansion of the AIDS Quilt Songbook Project from 1993 to the additions premiered on December 1, 2008 (World AIDS Day) at The Court Theater in Chicago, Illinois, entitled the "Chicago AIDS Quilt Songbook: A Benefit for Season of Concern." The AIDS Quilt Songbook project has sixty-seven documented additions, but only eighteen of the sixty-seven additions are collected. This thesis examines the events, compositions and experiences of the composers: Chris DeBlasio, Ricky Ian Gordon, Daniel Kallman, Cary John Franklin, and Evan Kuchar, who submitted compositions to the AIDS Quilt Songbook between 1991 and 2008. The compositions examined are: Walt Whitman in 1989 by DeBlasio, I Never Knew by Gordon, When ...
Date: August 2009
Creator: Seesholtz, John Clayton
Partner: UNT Libraries

Urban surface characterization using LiDAR and aerial imagery.

Description: Many calamities in history like hurricanes, tornado and flooding are proof to the large scale impact they cause to the life and economy. Computer simulation and GIS helps in modeling a real world scenario, which assists in evacuation planning, damage assessment, assistance and reconstruction. For achieving computer simulation and modeling there is a need for accurate classification of ground objects. One of the most significant aspects of this research is that it achieves improved classification for regions within which light detection and ranging (LiDAR) has low spatial resolution. This thesis describes a method for accurate classification of bare ground, water body, roads, vegetation, and structures using LiDAR data and aerial Infrared imagery. The most basic step for any terrain modeling application is filtering which is classification of ground and non-ground points. We present an integrated systematic method that makes classification of terrain and non-terrain points effective. Our filtering method uses the geometric feature of the triangle meshes created from LiDAR samples and calculate the confidence for every point. Geometric homogenous blocks and confidence are derived from TIN model and gridded LiDAR samples. The results from two representations are used in a classifier to determine if the block belongs ground or otherwise. Another important step is detection of water body, which is based on the LiDAR sample density of the region. Objects like tress and bare ground are characterized by the geometric features present in the LiDAR and the color features in the infrared imagery. These features are fed into a SVM classifier which detects bare-ground in the given region. Similarly trees are extracted using another trained SVM classifier. Once we obtain bare-grounds and trees, roads are extracted by removing the bare grounds. Structures are identified by the properties of non-ground segments. Experiments were conducted using LiDAR samples and Infrared imagery ...
Date: December 2009
Creator: Sarma, Vaibhav
Partner: UNT Libraries

God's Perfect Timing

Description: When I was thirty-three years old, I discovered I was an adoptee. In this memoir of secrecy and love, betrayal and redemption, I reflect on my early experiences as a doted-on only child firmly rooted in the abundant love of my adoptive family, my later struggles with depression and obsessive-compulsive disorder, my marriage to a fellow-adoptee, my discovery of my own adoption and the subsequent reunion with my birth family, my navigation through the thrills and tensions of newly complicated family dynamics, and my witness to God's perfect timing through it all.
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Date: August 2009
Creator: Rizzo, Steven
Partner: UNT Libraries

Integrating environmental data acquisition and low cost Wi-Fi data communication.

Description: This thesis describes environmental data collection and transmission from the field to a server using Wi-Fi. Also discussed are components, radio wave propagation, received power calculations, and throughput tests. Measured receive power resulted close to calculated and simulated values. Throughput tests resulted satisfactory. The thesis provides detailed systematic procedures for Wi-Fi radio link setup and techniques to optimize the quality of a radio link.
Date: December 2009
Creator: Gurung, Sanjaya
Partner: UNT Libraries

Interweaving History: The Texas Textile Mill and McKinney, Texas, 1903-1968.

Description: Texas textile mills comprise an untold part of the modern South. The bulk of Texas mills were built between 1890 and 1925, a compressed period of expansion in contrast to the longer developmental pattern of mills in the rest of the United States. This compression meant that Texas mill owners benefited from knowledge gained from mill expansion elsewhere, and owners ran their mills along the same lines as the dominant southeastern model. Owners veered from the established pattern when conditions warranted. This case study focuses on three mills in Texas that operated both independently and as a corporation for a total of sixty years. One mill in McKinney dominated the economy of a small town and serves as the primary focus of this paper. A second mill in Waco served a diversified economy in the center of the state; and the third mill, built in Dallas was concentrated in a major city in a highly competitive job market. All three of these mills will illuminate the single greatest difference between Texas mills and mills elsewhere, the composition of the labor force. Women did not dominate the mill labor force in Texas nor did children, except in limited cases, make-up a large portion of the workers. Today mill studies of southern mills have found only scattered textile factories with a preponderance of male employees, but in Texas this was the norm. This study demonstrates the unique features of McKinney's textile mill and its similarities to other mills in Texas and in the southeast.
Date: August 2009
Creator: Kilgore, Deborah Katheryn
Partner: UNT Libraries

Study of the effects of background and motion camera on the efficacy of Kalman and particle filter algorithms.

Description: This study compares independent use of two known algorithms (Kalmar filter with background subtraction and Particle Filter) that are commonly deployed in object tracking applications. Object tracking in general is very challenging; it presents numerous problems that need to be addressed by the application in order to facilitate its successful deployment. Such problems range from abrupt object motion, during tracking, to a change in appearance of the scene and the object, as well as object to scene occlusions, and camera motion among others. It is important to take into consideration some issues, such as, accounting for noise associated with the image in question, ability to predict to an acceptable statistical accuracy, the position of the object at a particular time given its current position. This study tackles some of the issues raised above prior to addressing how the use of either of the aforementioned algorithm, minimize or in some cases eliminate the negative effects
Date: August 2009
Creator: Morita, Yasuhiro
Partner: UNT Libraries

Interaction of learning approach with concept integration and achievement in a large guided inquiry organic class.

Description: A study was conducted to investigate the relationship of students' concept integration and achievement with time spent within a topic and across related topics in a large first semester guided inquiry organic chemistry class. Achievement was based on evidence of algorithmic problem solving; and concept integration was based on demonstrated performance explaining, applying, and relating concepts to each other. Twelve individual assessments were made of both variables over three related topics - acid/base, nucleophilic substitution and electrophilic addition reactions. Measurements included written, free response and ordered multiple answer questions using a classroom response system. Results demonstrated that students can solve problems without conceptual understanding. A second study was conducted to compare the students' learning approach at the beginning and end of the course. Students were scored on their preferences for a deep, strategic, or surface approach to learning based on their responses to a pre and post survey. Results suggest that students significantly decreased their preference for a surface approach during the semester. Analysis of the data collected was performed to determine the relationship between students' learning approach and their concept integration and achievement in this class. Results show a correlation between a deep approach and concept integration and a strong negative correlation between a surface approach and concept integration.
Date: August 2009
Creator: Mewhinney, Christina
Partner: UNT Libraries

The Great Debate continued: Does daily writing in kindergarten lead to invented spelling and reading?

Description: Many children in the United States cannot read on level by fourth grade. Traditionally, teachers have delayed reading instruction until first grade. However, involving children sooner in literary activities may provide skills needed to enable them to read on grade level. The purpose for this study was to determine the extent to which daily writing in kindergarten influences the development of invented spelling and learning to read. Five teachers modeled writing with 78 kindergarten children who wrote every day or almost every day for 20 weeks. There were 51 children in an experimental group, and 27 in a control group who were given a pretest and a posttest using the Observation Study (Clay, 1993). Results from a mixed model ANOVA indicated a significant difference between the control group and the experimental group on the Dictation Task F (1, 76) = 11.76, P≤ .001 and the Writing Test F (1, 76) = 4.33, P≤ .01. Results from a z-Test of dependent proportions indicated there were significant differences in the reading levels of the control group from the pretest to the posttest (z = 7.51, P ≥ .05) because (z = 7.51, Zcv = 1.96). The experimental group results from pretest to posttest were also statistically significant (z = 6.48, P ≥ .05) because (z = 6.48, Zcv = 1.96). At the end of kindergarten 82.35% of the experimental group was reading, while only 48.15% of the control group was reading. This research indicates that if kindergarten children are encouraged to write daily and use invented spelling there is a greater possibility they will enter first grade reading.
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Date: May 2003
Creator: Pierce, Laura Boehl
Partner: UNT Libraries

Magnetotransport Properties of AlxIn1-xAsySb1-y/GaSb and Optical Properties of GaAs1-xSbx

Description: Multilayer structures of AlxIn1-xAsySb1-y/GaSb (0.37 £ x £ 0.43, 0.50 £ y £ 0.52), grown by molecular beam epitaxy on GaSb (100) substrates were characterized using variable temperature Hall and Shubnikov-de Haas techniques. For nominally undoped structures both p and n-type conductivity was observed. The mobilities obtained were lower than those predicted by an interpolation method using the binary alloys; therefore, a detailed analysis of mobility versus temperature data was performed to extract the appropriate scattering mechanisms. For p-type samples, the dominant mechanism was ionized impurity scattering at low temperatures and polar optical phonon scattering at higher temperatures. For n-type samples, ionized impurity scattering was predominant at low temperatures, and electron-hole scattering dominated for both the intermediate and high temperature range. Analyses of the Shubnikov-de Haas data indicate the presence of 2-D carrier confinement consistent with energy subbands in GaAszSb1-z potential wells. Epilayers of GaAs1-xSbx (0.19<x<0.71), grown by MBE on semi-insulating GaAs with various substrate orientations, were studied by absorption measurements over the temperature range of 4-300 K. The various substrate orientations were chosen to induce different degrees of spontaneous atomic ordering. The temperature dependence of the energy gap (Eg) for each of these samples was modeled using three semi-empirical relationships. The resulting coefficients for each model describe not only the temperature dependence of Eg for each of the alloy compositions investigated, but also for all published results for this alloy system. The effect of ordering in these samples was manifested by a deviation of the value of Eg from the value of the random alloy. The presence of CuPt-B type atomic ordering was verified by transmission electron diffraction measurements, and the order parameter was estimated for all the samples investigated and found to be larger for the samples grown on the (111) A offcut orientations. This result strongly suggests ...
Date: May 2003
Creator: Lukic- Zrnic, Reiko
Partner: UNT Libraries

Low Temperature Polymeric Precursor Derived Zinc Oxide Thin Films

Description: Zinc oxide (ZnO) is a versatile environmentally benign II-VI direct wide band gap semiconductor with several technologically plausible applications such as transparent conducting oxide in flat panel and flexible displays. Hence, ZnO thin films have to be processed below the glass transition temperatures of polymeric substrates used in flexible displays. ZnO thin films were synthesized via aqueous polymeric precursor process by different metallic salt routes using ethylene glycol, glycerol, citric acid, and ethylene diamine tetraacetic acid (EDTA) as chelating agents. ZnO thin films, derived from ethylene glycol based polymeric precursor, exhibit flower-like morphology whereas thin films derived of other precursors illustrate crack free nanocrystalline films. ZnO thin films on sapphire substrates show an increase in preferential orientation along the (002) plane with increase in annealing temperature. The polymeric precursors have also been used in fabricating maskless patterned ZnO thin films in a single step using the commercial Maskless Mesoscale Materials Deposition system.
Date: December 2006
Creator: Choppali, Uma
Partner: UNT Libraries

Plays of Tennessee Williams as opera: An analysis of the elements of Williams's dramatic style in Lee Hoiby's Summer and Smoke and André Previn's A Streetcar Named Desire.

Description: There are two major, well-known operas based on plays of Tennessee Williams. He refused many times throughout his life to give permission for his play, A Streetcar Named Desire, to be set as an opera. It was not until the 1960s that he granted permission for Lee Hoiby to choose any of his plays as a basis for a new opera. Hoiby chose Summer and Smoke, a play which was written at approximately the same time as Streetcar. Lanford Wilson created the libretto for the opera which was given its premier in 1971 by the St. Paul Opera Association. In 1994 representatives of the Williams estate granted permission to the San Francisco Opera to commission an opera based on A Streetcar Named Desire. With a libretto by Philip Littell, the opera was composed by André Previn and given its premier in 1998. These two plays share common themes, character types, character relationships, and literary symbols due in part to the autobiographical nature of Williams's writings. The plays exhibit a cinematic nature and possess common dramatic elements such as the symbolic use of sets, props, and musical leitmotifs as a result of his attempts to create a new "plastic" style of theatre. The purpose of this thesis is to examine how each composer has captured the essence of Williams's dramatic style in these well known plays while dealing with stylistic elements that by nature could interfere in operatic composition. A brief biography of Williams is included to show the familial basis of his character types. Illustrations of his style serve as the basis for a comparison of the librettos to the plays. The musical analysis focuses on the composers' choices in dealing with Williams's poetic southern language, use of music, cinematic techniques, and complex characterizations.
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Date: December 2003
Creator: Lee, Kenneth Oneal
Partner: UNT Libraries

Development of a Hybrid Molecular Ultraviolet Photodetector based on Guanosine Derivatives

Description: Modern studies on charge transfer reaction and conductivity measurements of DNA have shown that the electrical behavior of DNA ranges from that of an insulator to that of a wide bandgap semiconductor. Based on this property of DNA, a metal-semiconductor-metal photodetector is fabricated using a self-assembled layer of deoxyguanosine derivative (DNA base) deposited between gold electrodes. The electrodes are lithographically designed on a GaN substrate separated by a distance L (50nm < L < 100nm). This work examines the electrical and optical properties of such wide-bandgap semiconductor based biomaterial systems for their potential application as photodetectors in the UV region wherein most of the biological agents emit. The objective of this study was to develop a biomolecular electronic device and design an experimental setup for electrical and optical characterization of a novel hybrid molecular optoelectronic material system. AFM results proved the usage of Ga-Polar substrate in conjugation with DG molecules to be used as a potential electronic based sensor. A two-terminal nanoscale biomolectronic diode has been fabricated showing efficient rectification ratio. A nanoscale integrated ultraviolet photodetector (of dimensions less than 100 nm) has been fabricated with a cut-off wavelength at ~ 320 nm.
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Date: December 2005
Creator: Liddar, Harsheetal
Partner: UNT Libraries

Narcissistic traits and parenting style: A closer look at maladaptive parenting through parent-child observations, parent self-report, and child self-report.

Description: The thrust of this paper was two-fold, 1) to confirm a 2-factor model of narcissism in women, and 2) to examine the relationship between narcissistic traits in mothers and several variables associated with parenting efficacy. Participants included 193 mother-child dyads. A 2-factor model of narcissism was confirmed in the present sample of mothers, suggesting that narcissistic traits in women may be manifested in distinct Overt and Covert forms. Contrary to expectations, Covert Narcissistic traits in mothers did not significantly correlate with observed parenting behaviors on the PCIA, including Positive Personal Comments (PPC) towards children, Negative Personal Comments (NPC), and Parental Nurturance. However, children's self-reported maternal rejection on the C-PARQ correlated positively with Covert Narcissistic traits in mothers, as did mother's self-reported dysfunctional parenting attitudes on the AAPI-2. Narcissistic traits in mothers correlated most strongly with risk of child physical abuse on the CAPI (r = .70). Results are also presented for the Overt Narcissism factor, which proved to be less stable as a factor. Overall, results emphasize the need for a more comprehensive understanding of narcissism for women, given its potential Implications for children's healthy development and parenting interventions.
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Date: August 2004
Creator: Collins, Michelle
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Piano Concerto No. 4 in D Minor, Op. 70 by Anton Rubinstein: An analytical and historical study.

Description: Anton Rubinstein was primarily recognized as one of the greatest pianists of his time. However, Rubinstein yearned for recognition as a composer and worked prodigiously to realize that goal. Unfortunately, Rubinstein's works were virtually unknown today. One of Rubinstein's finest compositions, the Piano Concerto in D Minor, op. 70 has been the most frequently performed. It is one of the first "Russian" concertos that was written by a Russian composer, and was performed in Russian concert halls instead of the homes of Russian aristocracy. It is also considered the most successful and harmonious convergent of various musical styles which influenced Rubinstein. However, there is no formal, detailed analysis of the Concerto in the entire music literature. Therefore, the main purpose of this dissertation is to provide a thorough study of the Concerto from an analytical and historical standpoint. Rubinstein was also one of the most eminent educators in Russia. The St. Petersburg Conservatory of Music, which Rubinstein helped found in 1862, has to this day produced some of the most influential musicians in Russia. The other purpose of this dissertation is to evaluate Rubinstein's role as music educator. An overview of Rubinstein's works for piano and orchestra offers a general idea of his compositional style. Literature on Anton Rubinstein currently available is limited. The two most valuable primary sources are Rubinstein's Autobiography of Anton Rubinstein, and Rubinstein's A Conversation on Music. Jeremy Norris's The Russian Piano Concerto, Volume I: The Nineteenth Century provides an insightful but short analysis on the Concerto. Sources discussing Anton Rubinstein as a pianist and an educator are relatively plentiful. Larry Sitsky's Anton Rubinstein: Annotated Catalog of Piano Works and Biography is an excellent work on Rubinstein's piano works. This dissertation includes four chapters: Chapter 1 - Introduction Chapter 2 - Rubinstein's works for piano and ...
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Date: May 2005
Creator: Peevey, Pui-King Cecilia
Partner: UNT Libraries