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Borel Determinacy and Metamathematics (open access)

Borel Determinacy and Metamathematics

Borel determinacy states that if G(T;X) is a game and X is Borel, then G(T;X) is determined. Proved by Martin in 1975, Borel determinacy is a theorem of ZFC set theory, and is, in fact, the best determinacy result in ZFC. However, the proof uses sets of high set theoretic type (N1 many power sets of ω). Friedman proved in 1971 that these sets are necessary by showing that the Axiom of Replacement is necessary for any proof of Borel Determinacy. To prove this, Friedman produces a model of ZC and a Borel set of Turing degrees that neither contains nor omits a cone; so by another theorem of Martin, Borel Determinacy is not a theorem of ZC. This paper contains three main sections: Martin's proof of Borel Determinacy; a simpler example of Friedman's result, namely, (in ZFC) a coanalytic set of Turing degrees that neither contains nor omits a cone; and finally, the Friedman result.
Date: December 2001
Creator: Bryant, Ross
System: The UNT Digital Library

Characterization of Moraxella bovis Aspartate Transcarbamoylase

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Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in the pyrimidine biosynthetic pathway. Bacterial ATCases have been divided into three classes, class A, B, and C, based on their molecular weight, holoenzyme architecture, and enzyme kinetics. Moraxella bovis is a fastidious organism, the etiologic agent of infectious bovine keratoconjunctivitis (IBK). The M. bovis ATCase was purified and characterized for the first time. It is a class A enzyme with a molecular mass of 480 to 520 kDa. It has a pH optimum of 9.5 and is stable at high temperatures. The ATCase holoenzyme is inhibited by CTP > ATP > UTP. The Km for aspartate is 1.8 mM and the Vmax 1.04 µmol per min, where the Km for carbamoylphosphate is 1.05 mM and the Vmax 1.74 µmol per min.
Date: December 2001
Creator: Hooshdaran, Sahar
System: The UNT Digital Library
Characterization of the Aspartate Transcarbamoylase that is Found in the pyrBC’ Complex of Bordetella Pertussis (open access)

Characterization of the Aspartate Transcarbamoylase that is Found in the pyrBC’ Complex of Bordetella Pertussis

An aspartate transcarbamoylase (ATCase) gene from Bordetella pertussis was amplified by PCR and ligated into pT-ADV for expression in Escherichia coli. This particular ATCase (pyrB) was an inactive gene found adjacent to an inactive dihydroorotase (DHOase) gene (pyrC'). This experiment was undertaken to determine whether this pyrB gene was capable of expression alone or if it was capable of expression only when cotransformed with a functional pyrC'. When transformed into E. coli TB2 pyrB-, the gene did not produce any ATCase activity. The gene was then co-transformed into E. coli TB2 pyrB- along with a plasmid containing the pyrC' gene from Pseudomonas aeruginosa and assayed for ATCase activity. Negative results were again recorded.
Date: December 2001
Creator: Dill, Michael T
System: The UNT Digital Library

Characterizaton of Triethoxyfluorosilane and Tetraethoxysilane Based Aerogels

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Aerogels are highly porous, low dielectric constant (low k) materials being considered by the semiconductor industry as an interlayer dielectric. Low k materials are needed to overcome capacitance problems that limit device feature sizes. Precursors triethoxyfluorosilane (TEFS) and tetraethoxysilane (TEOS) were used to prepare bulk aerogels. Samples were prepared by sol-gel methods, and then carbon dioxide supercritically-dried. Effects of varying the water to precursor ratio were studied with respect to aerogel properties and microstructure. Methods of analysis for this study include FTIR-ATR, TEM, RBS, EDS, SEM, dielectric constant determination by impedance and surface area by gas adsorption. Si-F bonds were determined to be present in both acid- and base-catalyzed TEFS as well as HF-catalyzed TEOS. Fluorine promotes a fractal network microstructure as opposed to a particle-like microstructure. Surface area and dielectric constant were determined to increase slightly with increases in the water to precursor ratio.
Date: December 2001
Creator: Roepsch, Jodi Ann
System: The UNT Digital Library
Constructed Images: The Influences of News Organizations and Socialization in Photojournalism (open access)

Constructed Images: The Influences of News Organizations and Socialization in Photojournalism

Media sociologists have produced much research on the systems of production of media content. Photojournalism, however, largely has been ignored in these studies. This paper presents the findings of an ethnographic study of work routines and photojournalism practices at three newspapers. The study explored the extent to which routines and practices are affected by professional norms and values and organizational needs and beliefs. The study also explored how these factors influence the content and aesthetic qualities of newspaper photographs. Findings suggest that photo editors and photojournalists operate under many of the same constraints as other media workers. The findings also show that photojournalists are socialized to newspapers. expectations by fellow photographers and photo editors. To gauge professional accomplishments, photojournalists rely on peers, professional organizations and competitions.
Date: December 2001
Creator: Bolack, Michell
System: The UNT Digital Library

Development of a Pre-Impact Environmental Site Characterization for the Bryan Mound, Texas Strategic Petroleum Reserve

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This thesis presents a model for developing site-specific contingency plans to be used during spill response, remediation, and post-spill monitoring using the Strategic Petroleum Reserve's Bryan Mound site as a case study. Bird and vegetation observations provide baseline data for biological conditions, and sediment sampling for total petroleum hydrocarbons serves as a chemical component of the model. Results demonstrate previously unknown conditions that would hinder remediation and affect the persistence of petroleum contaminants. Results also established previously unmapped dominant bird and vegetation types likely to be impacted by a spill at the site. This model points to a reconsideration of individual facilities' responsibilities when planning for large-scale disasters and protecting the sensitive ecosystems surrounding their sites.
Date: December 2001
Creator: Hernandez, Sylvia A.
System: The UNT Digital Library
Dynamic Resource Management in RSVP- Controlled Unicast Networks (open access)

Dynamic Resource Management in RSVP- Controlled Unicast Networks

Resources are said to be fragmented in the network when they are available in non-contiguous blocks, and calls are dropped as they may not end sufficient resources. Hence, available resources may remain unutilized. In this thesis, the effect of resource fragmentation (RF) on RSVP-controlled networks was studied and new algorithms were proposed to reduce the effect of RF. In order to minimize the effect of RF, resources in the network are dynamically redistributed on different paths to make them available in contiguous blocks. Extra protocol messages are introduced to facilitate resource redistribution in the network. The Dynamic Resource Redistribution (DRR) algorithm when used in conjunction with RSVP, not only increased the number of calls accommodated into the network but also increased the overall resource utilization of the network. Issues such as how many resources need to be redistributed and of which call(s), and how these choices affect the redistribution process were investigated. Further, various simulation experiments were conducted to study the performance of the DRR algorithm on different network topologies with varying traffic characteristics.
Date: December 2001
Creator: Iyengar Prasanna, Venkatesan
System: The UNT Digital Library

The Effect of Punishment Threat on Children's Ability to Resist Temptation to Transgress and Lie

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Children's response to a resistance-to-temptation (RTT) task was investigated under three punishment threat conditions: negative consequence, removing an anticipated reward, and no explicit punishment. Ninety first and second graders participated in the RTT task and seventy-three parents completed the Behavior Assessment System for Children and the Psychopathy Screening Device. As only 4% of children transgressed, results are unclear. Hypotheses tested using approximations of transgression showed no differences in RTT. Children with temperaments characterized by hyperactivity, impulsivity, attention problems, and conduct problems (HIA-CP) had the highest levels of psychopathic traits compared to all others. In addition, spanked children were rated as having significantly more behavioral problems than non-spanked children. Limitations of the current study and suggestions for future research are discussed.
Date: December 2001
Creator: Collins, Michelle
System: The UNT Digital Library
The Effects of a College Human Sexuality Course on Students' Sexual Knowledge, Attitude, and Behavior. (open access)

The Effects of a College Human Sexuality Course on Students' Sexual Knowledge, Attitude, and Behavior.

Using an experimental-comparison group design, data were collected at the beginning and end of a semester to assess the effect of a human sexuality course on students' sexual knowledge, sexual attitude, and sexual behaviors. Data analysis by t-tests showed statistical differences between the experimental and comparison group only on sexual knowledge scores ( p < .001), with the experimental group scoring higher. T-tests showed statistical difference between males and females in sexual attitude (p< .001) and sexual behavior (p< .001) with women scoring higher than men in the experimental group, and also when experimental and control groups were combined. Although not statistically significant, women scored higher in sexual knowledge than males.
Date: December 2001
Creator: Smith, Jolene A.
System: The UNT Digital Library

The Effects of Color Concentrate in Polyolefins.

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Throughout history consumer products were generally manufactured from wood and metal. They either had to hold their natural color or become subject to painting. When plastics entered the industry, it was recognized for its ease of shaping, re-usability, physical properties and its low cost. One of plastics' greatest benefits is its ability to hold a given color from within allowing it to avoid use of paint. This paper will give a brief overview on the effects of pigments when incorporated in a polyolefin. It will provide a classification of the main types of pigments and how each effect the properties of the product through: crystallization, weatherability, opacity, coloristic values and of course viscosity.
Date: December 2001
Creator: Flora, Paul
System: The UNT Digital Library
The Effects of Graduated Exposure, Modeling, and Contingent Social Attention on Tolerance to Skin Care Products with Children Who Have Autism. (open access)

The Effects of Graduated Exposure, Modeling, and Contingent Social Attention on Tolerance to Skin Care Products with Children Who Have Autism.

The effects of graduated exposure, modeling and contingent social attention on tolerance to skincare products were evaluated with two boys with autism who displayed tactile defensiveness. Upon each presentation step of skincare products the number of positive and negative responses and successful step completion were measured. Procedures included modeling, presenting graduated opportunities, and providing social attention for step completion. Step advancement occurred if a child engaged in a step independently, without excessive refusals. A changing criterion design and a multiple baseline were employed to evaluate effects of this treatment package. Children demonstrated more positive and fewer negative responses as they completed the graduated steps. Effects maintained in follow-up observations.
Date: December 2001
Creator: South, Ellyn M.
System: The UNT Digital Library
The Effects of Restricting the Response Space and Self-evaluation on Letter Quality in Beginning and Experienced Handwriters. (open access)

The Effects of Restricting the Response Space and Self-evaluation on Letter Quality in Beginning and Experienced Handwriters.

This study analyzed the effects of restricting the response space and selfevaluation on students' handwriting quality in two beginning handwriters and two experienced handwriters. Students executed letters with and without using a transparent overlay, in a multiple-baseline-across-letters design. The use of the transparent overlay included drawing letters in a space restricted by the transparency; overlaying a model letter on top of the written letter and; evaluating if the two letters matched. Letter quality immediately improved when overlays were used, and handwriting quality maintained when the writing response was not restricted by the overlay transparency. Prompting and feedback were delivered contingent on on-task behavior. Analysis was based on three different measurement systems.
Date: December 2001
Creator: LePage, Julia
System: The UNT Digital Library

An Etiology of Juvenile Homicide in Dallas, Texas: 1988-1997

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This research analyzed all juveniles involved in a homicide, both victims and offenders, in the city of Dallas, Texas from the years 1988 through 1997. This study addressed several research questions including the identification of risk factors common to both victims and offenders. Data for this study was obtained from the homicide files of the Dallas Police Department. The findings in part identify specific profiles of the victims and offenders, as well as identifying comparisons of risk factors between the two groups. Also identified are the relationships between the offenders and victims. Conclusions from this research present implications for law enforcement agencies, as well as furthering the etiology of juvenile homicide.
Date: December 2001
Creator: Haynes, Joseph
System: The UNT Digital Library

Immediate and subsequent effects of fixed-time food presentations on automatically maintained mouthing.

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Several studies have demonstrated that fixed-time (FT) schedules of stimulus delivery can function to reduce a variety of behaviors. The purpose of this study was to evaluate the immediate and subsequent effects of FT food deliveries on mouthing. In Phase 1, a preference assessment showed that caramel popcorn, chocolate cookies and pretzels were highly preferred food items. Thus, providing the basis for use of food items during treatment. In Phase 2, a functional analysis showed that mouthing was a nonsocially maintained problem behavior. Phase 3 demonstrated the use of FT schedules of food deliveries as treatment for nonsocially maintained mouthing. Results indicated that FT schedules of food significantly reduced mouthing. In addition, levels of mouthing observed during post-FT observations were reliably lower than pre-FT observations. Treatment effects, operative mechanisms responsible for the treatment effects and the experimental arrangement used to investigate varying FT schedules are discussed.
Date: December 2001
Creator: Simmons, Jason N.
System: The UNT Digital Library

A laboratory course in experimental genetics for the biology major.

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This manual has been designed for a class of twenty- four students concurrently enrolled in the lecture course. The laboratory aids in the learning process and fosters an interest in the science of genetics. This manual and the experiments contained within are both informative and fun. The manual correlates with and expands upon the genetics course. Each investigation, with the exception of the Drosophila melanogaster project, can be completed in a 3-4 hour timeframe. This manual provides a “hands on” experience of theories simply discussed in the lecture course. This manual is intended to be a one-source manual where each investigation is designed to include an adequate introduction. Special attention has been given for each investigation with both the student and instructor in mind.
Date: December 2001
Creator: Lux, Melissa McNeil
System: The UNT Digital Library
Measuring the Effects of the TYC Gainesville Resocialization Program on Juvenile Offender Resiliency Levels (open access)

Measuring the Effects of the TYC Gainesville Resocialization Program on Juvenile Offender Resiliency Levels

An analysis of the effects of resocialization programming on juvenile offender resiliency levels was conducted with 220 juveniles committed to a maximum security facility. Data were examined on the subjects' age, race/ethnicity, length of time at the facility, level of resocialization, and resiliency score. The resocialization programming contains cognitive and social components that would be instrumental in augmenting juvenile offender resiliency levels. Analysis of the variables did not show a significant increase in juvenile offender resiliency levels. The results did display that students who were at the facility longer and who were in the older age groups had higher levels of resocialization.
Date: December 2001
Creator: Kronvall, Veronica L
System: The UNT Digital Library

Microwave Cavity Test for Superconductivity

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The first part of this paper describes the Meissner effect in superconductors which serves as the most definitive evidence for superconductivity. It is shown that the microwave perturbation technique may be used to demonstrate this effect. By measuring the changes of resonant frequency and inverse quality factor Q of a microwave cavity with a small volume of sample loading, the Meissner effect can be shown by using the Slater perturbation equation. The experimental system is described with details and the basic principle of each component discussed. The second part of this work describes the technique employed to do the actual measurements. The experiments were conducted on samples of Gallium Arsenide (GaAs) and lead zirconate titanate (PZT) to look for the possible high temperature superconductivity properties. Results of these experiments are presented and discussed. Conclusion and suggestions to future exploration are made.
Date: December 2001
Creator: Tang, Shan
System: The UNT Digital Library

Mineral-filled polypropylene: Improvement of scratch resistance

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A potential alternative to acrylonitrile-butadiene-styrene (ABS) and polycarbonate+ABS (PC+ABS), pigmented mineral-filled polypropylene (PP) finds an opening in automotive interior components such as instrument panels, knee bolsters, consoles, etc. Because of the lack of surface aesthetics, pigmented mineral-filled PP is experiencing a limitation to its acceptance in many applications. This study focuses on exploring various mineral fillers and additives in polypropylene to provide a material with enhanced scratch resistance. Several physical properties including Rockwell and Shore D hardness are investigated, and it is determined that Filler W improves scratch resistance. It is also determined that Filler T-filled-PP has poor scratch resistance even with the addition of a lubricant.
Date: December 2001
Creator: Khatib, Jamal F.
System: The UNT Digital Library
A New Circle (open access)

A New Circle

This reflexive documentary film explores the Alabama-Coushatta Indian Tribe of Texas and examines questions of cultural identity. The twenty-one minute film uses footage of cultural events, reservation landscape, photographs, and interviews to bring the viewer into the lives of the Alabama-Coushatta people. The written portion of this thesis details the entire processes of making the film, from the proposal stage to the post-production stage. This includes an examination of the film's evolution from using a proposed ethnographic approach to one less scientific and more personal.
Date: December 2001
Creator: Shutt, Jason
System: The UNT Digital Library
NMR study of 2-ethylhexyllithium aggregate and 2- ethylhexyllithium/lithium 2-ethyl-1-hexoxide mixed aggregates. (open access)

NMR study of 2-ethylhexyllithium aggregate and 2- ethylhexyllithium/lithium 2-ethyl-1-hexoxide mixed aggregates.

A 1H, 13C, and 6Li NMR study of 2-ethylhexyllithium showed that 2- ethylhexyllithium exists solely as a hexamer in cyclopentane solution over the temperature range from 25 to -65 °C. Furthermore, 2-ethylhexyllithium and lithium 2- ethyl-1-hexoxide were shown to form mixed aggregates when the alkoxide was formed in situ by reacting 2-ethylhexyllithium with 2-ethyl-1-hexanol. A multinuclear, variable temperature NMR study of a sample with an O:Li ratio of 0.2 led to the identification of at least four such aggregates, one of which was found to be a hexamer with the composition R5(RO)Li6. Studies of samples with higher O:Li ratios, up to 0.8, showed additional mixed aggregates present. All solutions containing mixed aggregates were also shown to contain hydrocarbon soluble lithium hydride. A study of lithium 2-ethyl-1- hexoxide indicated that it aggregates in solution as well.
Date: December 2001
Creator: Petros, Robby A.
System: The UNT Digital Library

Practices and attitudes toward alternative medicine among college students.

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This study assesses practices of college students (N=913) toward alternative medicine, relationships of students' health locus of control with practices of alternative medicine, and relationships of students' attitudes toward alternative medicine and health locus of control. A principal components factor analysis established construct validity of the author-designed Attitude Toward Alternative Medicine Scale, extracting three factors: Holistic Attitude/Control, Safety, and Satisfaction. Holistic Attitude/Control predicted use of alternative medicine (Wald =61.9, p < .01). A principal components factor analysis established construct validity of the Multidimensional Health Locus of Control Scale, extracting three factors: Internal Health Locus of Control, External-Chance, and External-Powerful Others. Internal Health Locus of Control significantly correlated with Holistic Attitude/Control (r = .35, p =.01).
Date: December 2001
Creator: Fogle, Peggy
System: The UNT Digital Library
The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network. (open access)

The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network.

Polymer hydrogel films change their properties in response to environmental change. This remarkable phenomenon results in many potential applications of polymer hydrogel films. In this thesis colored thermo-sensitive poly(N-isopropylacrylamide) (PNIPAAm) hydrogel film was prepared by firstly synthesizing polymer latex and secondarily crosslinking the nanoparticles and casting the polymers onto glass. The shape-memory effect has been observed when changing the environmental temperature. The temperature-dependent of turbidity of polymer hydrogel film was measured by HP UVVisible spectrophotometer. This intelligent hydrogel might be used in chemomechanical systems and separation devices as well as sensors. Polymer adsorption plays an important role in many products and processes. In this thesis, surfactant-free three-dimensional polystyrene (PS) nanoparticle network has been prepared. The infrared spectroscopy and solubility experiment are performed to prove the crosslinking mechanism, also the BET method was used to measure the adsorption and desorption of polystyrene network. The BET constant (C) is calculated (C=6.32). The chemically bonded polymer nanoparticle network might have potential applications as catalyst or used for chromatographic columns.
Date: December 2001
Creator: Zhou, Bo
System: The UNT Digital Library
Relations between Child Molesters' Self-Perceptions and Treatment Engagement (open access)

Relations between Child Molesters' Self-Perceptions and Treatment Engagement

Researchers emphasize the role of cognitions in sex offenders' molesting behaviors. Although cognitions are important, little research has examined child molesters' thoughts about themselves in relation to their engagement in treatment. In this study, the NEO-Personality Inventory (NEO-PI-R) was administered to 67 child molesters. Child sexual offenders rated themselves and their view of a typical child molester using two NEO-PI-R versions. The degree to which child sex offenders identify themselves with their view of a typical child molester, and this agreement's relation with engagement in treatment, were investigated. The view that child sex offenders hold about themselves in relation to a typical child molester showed no relation to treatment engagement or length of time in treatment. However, this self-perception was related to the number of children abused.
Date: December 2001
Creator: Altman, Adrianne
System: The UNT Digital Library
The relationships between insight, psychopathological symptoms, and neurocognitive function in psychotic disorders. (open access)

The relationships between insight, psychopathological symptoms, and neurocognitive function in psychotic disorders.

Many psychotic patients fail to admit they are mentally ill. The current study evaluated the associations between insight, specific symptoms, and neurocognitive impairments. Thirty-three acute inpatients with a schizophrenia, schizoaffective disorder, or psychotic disorder NOS diagnosis were rated on the SAIE, Birchwood's IS, and the BPRS. Neurocognitive assessments of attention and frontal lobe functioning were also conducted. Stepwise multiple regression analyses found composites representing delusions, disorganization, and anxiety/depression, as well as CPT-IP shapes hit rate, served as significant predictors of total insight or the specific insight dimensions. At least for acute patients, symptoms tended to have stronger relationships with and were more regularly predictive of insight than neurocognitive measures, though the attentional task associated with right hemisphere functioning, contributed significantly.
Date: December 2001
Creator: Gonterman, Andrea R.
System: The UNT Digital Library