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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 … more
Date: May 2003
Creator: Lukic- Zrnic, Reiko
Partner: UNT Libraries
open access

Synthesis and characterization of 2-chloro-3-benzylthiopyrrolo[1,2-a]- benzimidazol-1-one and 2,3-di(benzylthio)pyrrolo[1,2-a]benzimidazol-1-one.

Description: The reaction between o-phenylenediamine and 2,3-dichloromaleic anhydride has been probed and found to give 2,3-dichloropyrrolo[1,2-a]- benzimidazol-1-one as the major product. Chlorine substitution in 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one by added benzylthiol occurs in the presence of pyridine to provide the corresponding monosulfide and disulfide derivatives. The first benzylthiol ligand undergoes reaction at the C-3 position of the five-membered pyrrolo-1-one ring, with the addition of… more
Date: December 2003
Creator: Huang, Shih-Huang
Partner: UNT Libraries
open access

Analysis of Hypothetical Promoter Domains of DKFZp564A1164, NPHS1 and HSPOX1 Genes

Description: For this study, a high throughput method for identifying and testing regulatory elements was examined. In addition, the validity of promoters predicted by FirstEF was tested. It was found that by combining computer based promoter and first exon predictions from FirstEF (Davuluri et al., 2001) with PCR-based cloning to generate luciferase reporter constructs, and by testing reporter activity in cultured mammalian cells plated in a 96 well format one could identify promoter activity in a relative… more
Date: November 29, 2003
Creator: Hammond, S S
Partner: UNT Libraries Government Documents Department
open access

A measurement of forward-backward charge asymmetry of electron-positron pairs in proton-antiproton collision at 1.8 TeV

Description: The authors present a measurement of the mass dependence of the forward-backward charge asymmetry for e{sup +}e{sup -} pairs resulting from {gamma}*/Z decays with mass M{sub ee} > 40 GeV/c{sup 2}. The Run II data sample consists of 72 pb{sup -1} of data, which was collected by the CDF detector in {bar p}p collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron. The measurement is compared with predictions from the Standard Model.
Date: December 1, 2003
Creator: Veramendi, Gregory Francisco
Partner: UNT Libraries Government Documents Department

Synthesis and X-ray Diffraction Structure of 8,9-Dichloropyrrolo[1,2-a]perimidin-10-one

Description: Treatment of dichloromaleic anhydride and 1,8-diaminonaphthalene in either benzene or toluene under refluxing conditions gives low yields of the new heterocyclic compound 8,9-dichloropyrrolo[1,2-a]perimidin-10-one. This product has been isolated and characterized in solution by NMR, IR, and UV/vis spectroscopies, and the solid-state structure of 8,9-dichloropyrrolo[1,2-a]perimidin-10-one has been established by X-ray crystallography. The nature of the HOMO and LUMO levels of 8,9-dichloropyrrolo… more
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Date: August 2003
Creator: Chen, Tao
Partner: UNT Libraries
open access

A Search for Supersymmetric Higgs Bosons in the Di-tau Decay Mode in Proton - Anti-proton Collisions at 1.8 TeV

Description: A search for directly produced Supersymmetric Higgs Bosons has been performed in the di-tau decay channel in 86.3 {+-} 3.5 pb{sup -1} of data collected by CDF during Run1b at the Tevatron. They search for events where one tau decays to an electron and the other tau decays hadronically. They perform a counting experiment and set limits on the cross section for Higgs production in the high tan {beta} region of the m{sub A}-tan {beta} plane. For a benchmark parameter space point where m{sub A} = 1… more
Date: September 1, 2003
Creator: Connolly, Amy Lynn
Partner: UNT Libraries Government Documents Department
open access

Structural studies of conformational changes of proteins upon phosphorylation: Structures of activated CheY, CheY-N16-FliM complex, and AAA {sup +} ATPase domain of NtrC1 in both inactive and active states

Description: Protein phosphorylation is a general mechanism for signal transduction as well as regulation of cellular function. Unlike phosphorylation in eukaryotic systems that uses Ser/Thr for the sites of modification, two-component signal transduction systems, which are prevalent in bacteria, archea, and lower eukaryotes, use an aspartate as the site of phosphorylation. Two-component systems comprise a histidine kinase and a receiver domain. The conformational change of the receiver domain upon phosphor… more
Date: April 10, 2003
Creator: Lee, Seok-Yong
Partner: UNT Libraries Government Documents Department
open access

Seach for second - generation leptoquarks in proton - anti-proton collisions

Description: This document describes the search for second-generation leptoquarks (LQ{sub 2}) in around 114pb{sup -1} of p{bar p} collisions, recorded with the D0 detector between September 2002 and June 2003 at a centre-of-mass energy of {radical}s = 1.96TeV. The predictions of the Standard Model and models including scalar leptoquark production are compared to the data for various kinematic distributions. Since no excess of data over the Standard Model prediction has been observed, a lower limit on the le… more
Date: December 1, 2003
Creator: Christiansen, Tim U.
Partner: UNT Libraries Government Documents Department

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… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Pierce, Laura Boehl
Partner: UNT Libraries
open access

Investigation of the Pressure Dependence of SO3 Formation

Description: The kinetics of the pressure dependent O + SO2 + Ar reaction have been investigated using laser photolysis resonance fluorescence at temperatures of 289 K, 399 K, 581 K, 699 K, 842 K and 1040 K and at pressures from 30-665 torr. Falloff was observed for the first time in the pressure dependence. Application of Lindemann theory yielded an Arrhenius expression of k(T) = 3.3 x 10-32exp(-992/T) cm6 molecule-1 s-1 for the low pressure limit and k(T) = 8.47 x 10-14exp(-468/T) cm3 molecule-1 s-1 for t… more
Date: December 2003
Creator: Naidoo, Jacinth
Partner: UNT Libraries
open access

The Effect of a Laboratory-based, In-context, Constructivist Teaching Approach on Preservice Teachers' Science Knowledge and Teaching Efficacy.

Description: This study began with a concern about elementary teachers, as a whole, avoiding the teaching of science in the elementary classroom. The three main factors noted as reasons for this avoidance were: (1) minimum science requirements to reach certification, leading to a lack of preparedness; (2) lack of exposure to science in elementary school; and (3) general dislike for and understanding of science leading to a low self-efficacy in science teaching. The goal of the Environmental Science Lab for … more
Date: May 2003
Creator: Thompson, Ruthanne
Partner: UNT Libraries
open access

Memento

Description: Chapter 1 describes my previous jewelry work related to my interest in body parts and other materials as medium and lockets. The questions in the statement of problem deal with how the use of a specific body site, color and incorporation of body parts in my jewelry make my work more intimate to the wearer. Chapter 2 discusses the work I focused around the questions proposed in Chapter 1. Important points are: a more focused way of using specific body sites to support my ideas, the use of differ… more
Date: May 2003
Creator: Kataoka, Masumi
Partner: UNT Libraries
open access

Pyrimidine Genes in Pseudomonas Species

Description: This thesis is a comparative study of gene arrangements in Pseudomonas species, and is organized into three major sections. The first section compares gene arrangements for different pathways in Pseudomonas aeruginosa PAO1 to determine if the gene arrangements are similar to previous studies. It also serves as a reference for pyrimidine gene arrangements in P. aeruginosa. The second part compares the physical, and genetic maps of P. aeruginosa PAO1 with the genome sequence. The final secti… more
Date: December 2003
Creator: Roush, Wendy A.
Partner: UNT Libraries

Characterization of Iron Oxide Deposits Formed at Comanche Peak Steam Electric Station

Description: The presence of deposits leading to corrosion of the steam generator (SG) systems is a major contributor to operation and maintenance cost of pressurized water reactor (PWR) plants. Formation and transport of corrosion products formed due to the presence of impurities, metallic oxides and cations in the secondary side of the SG units result in formation of deposits. This research deals with the characterization of deposit samples collected from the two SG units (unit 1 and unit 2) at Comanche P… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Namduri, Haritha
Partner: UNT Libraries
open access

Study of Interactions Between Diffusion Barrier Layers and Low-k Dielectric Materials for Copper/Low-k Integration

Description: The shift to the Cu/low-k interconnect scheme requires the development of diffusion barrier/adhesion promoter materials that provide excellent performance in preventing the diffusion and intermixing of Cu into the adjacent dielectrics. The integration of Cu with low-k materials may decrease RC delays in signal propagation but pose additional problems because such materials are often porous and contain significant amounts of carbon. Therefore barrier metal diffusion into the dielectric and the… more
Date: December 2003
Creator: Tong, Jinhong
Partner: UNT Libraries
open access

Voyeurism and Fetishism

Description: This problem in lieu of thesis concerns voyeurism and fetishism and how they relate to art. It addresses at voyeurism from both sides of the gaze. It describes a body of work that was created to explore the relationship between the voyeur and the fetish object and the viewer and the art object.
Date: May 2003
Creator: De Anda, Veronica
Partner: UNT Libraries
open access

Investigation of Pyrimidine Salvage Pathways to Categorize Indigenous Soil Bacteria of Agricultural and Medical Importance and Analysis of the Pyrimidine Biosynthetic Pathway's Enzyme Properties for Correlating Cell Morphology to Function in All Phases of Growth

Description: This dissertation comprises three parts and is presented in two chapters. Chapter 1 concerns Arthrobacter, a bacterium with an intriguing growth cycle. Whereas most bacteria exist as either a rod or coccus, this bacterium shares the rod/coccus lifestyle. It therefore seemed important to examine the growth regulatory pathways from the rod and coccus. The committed step, that catalyzed by aspartate transcarbamoylase (ATCase), in the pyrimidine biosynthetic pathway was chosen. The ATCase in Arthr… more
Date: May 2003
Creator: Meixner, Jeffery Andrew
Partner: UNT Libraries
open access

A Descriptive Study of the Intelligence Community in the United States of America

Description: This treatise represents a descriptive study of the intelligence community in the United States. It explores the ramifications of terrorism on the intelligence function, post September 11, 2001. In-depth discussions concerning the structure of the U.S. intelligence community are presented as well as a focus on the defined steps of the intelligence process: planning and directions, collection, analysis, production, and dissemination. The final aspect of this study poses questions and issues rela… more
Date: May 2003
Creator: Ucak, Hursit
Partner: UNT Libraries
open access

Woven Music

Description: When I am weaving I listen to music and notice that my hands and feet fall into a rhythm. This connection reminds me of playing the piano. I took a closer look at weaving drafts; the movement of the threading setup reminded me of the notes on musical scores. This relationship inspired me to see what textures I could achieve by actually weaving the musical notes. The focus of my study is the exploration of the relationships between weaving and music utilizing elements and principles found in bot… more
Date: May 2003
Creator: Jackson, Melanie S.
Partner: UNT Libraries
open access

Reaching for Understanding: Exploring the Potential of Four-Year-Old Children to Understand Works of Art

Description: This study was designed to examine how four-year-old children might be able to respond and interpret works of art. Informed by Jean Piaget's and Lev Vygotsky's theories of cognitive development, and building on Micheal Parsons' and Abigail Housen's theories of aesthetic development, the study investigated whether or not four-year-olds are able to expand their initial responses to achieve deeper levels of understanding about works of art.
Date: May 2003
Creator: Smith, Maria Carmen
Partner: UNT Libraries
open access

The predictive influence of variables in three different academic learning environments on the intentions of music education majors to leave the degree program.

Description: Attrition rates among students in music teacher training programs have contributed to a shortage of qualified music teachers for the nation's schools. The purpose of this study was to investigate the predictive relationship of academic variables in three different learning environments and the intent of a select population of music education majors to leave the degree program. The study drew upon the work of Tinto, Bean and Astin to form a theoretical foundation for examining variables unique t… more
Date: May 2003
Creator: Corley, Alton L.
Partner: UNT Libraries
open access

Harmonization of Accounting Practices Among IAS Firms Listed in the U.S. and Its Capital Market Implications

Description: The focus of the study is on financial reporting for non-U.S. firms registered with the Securities Exchange Commission (SEC) but using International Accounting Standards (IAS). This study addresses two issues, (1) whether the comparability of financial reporting among firms using IAS in credit and equity financing jurisdictions increases over time and (2) the associated capital market implications. The motivation for the study is the SEC's ongoing assessment of IAS for possible use by non-U.S. … more
Date: December 2003
Creator: Paananen, Mari
Partner: UNT Libraries
open access

Educators' Technology Level of Use and Methods for Learning Technology Integrations.

Description: The purpose of this study was to describe technology learning methods that teachers attend and perceive as effective. The goal was to provide district personnel data that may be utilized when planning for more effective technology staff development. This study examined (1) the methods of learning instructional technology that are being utilized by teachers and administrators and (2) why these methods are being utilized in two Texas school districts. Data was collected from educators via an onli… more
Date: August 2003
Creator: Griffin, Darlene Ann
Partner: UNT Libraries

Self-Optimizing Dynamic Finite Functions

Description: Finite functions (also called maps) are used to describe a number of key computations and storage mechanisms used in software and hardware interpreters. Their presence spread over various memory and speed hierarchies in hardware and through various optimization processes (algorithmic and compilation based) in software, suggests encapsulating dynamic size changes and representation optimizations in a unique abstraction to be used across traditional computation mechanisms. We developed a memory a… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: December 2003
Creator: Jeripothula, Ramesh
Partner: UNT Libraries
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