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The Role of Individuation Processes in the Launching of Children into Adulthood

Description: The purpose of this study was to examine the extent to which levels of individuation and separation in adulthood would predict adjustment to the empty nest transition. Two-hundred and twenty-seven adults (M age = 48) who had experienced the empty nest within the last year completed a battery of scales assessing individuation from family of origin, spouse, and children as well as measures of adjustment, role strain, coping, and sex role attitudes. MANOVAS and hierarchical regression analyses suggested that levels of individuation from one's family of origin, spouse, and children differentially affect one's adjustment to, and coping with, the experience of launching of the youngest child from the home. Empty nest parents who are less differentiated from their own parents, from their spouses, and from their children reported a more negative impact of the empty nest in terms of more overall stress and role strain, more negative mood, and less life satisfaction than did empty nest parents who were more differentiated with regard to parents, spouse, and children. Results regarding the impact of individuation on empty nest adjustment regarding sex role attitudes were less clear cut, and may reflect cohort differences in work role opportunities for women and a parallel redefinition of the work role/parent role dichotomy for men. The data also suggest that women and men experience the empty nest transition differently, with women experiencing more distress and negative mood, supporting the notion that women, who define themselves in a context of relationship may experience more distress at a time when significant relationships are in flux. However, additional results which indicated significantly more proactive and adaptive coping strategies for women as compared to men suggest that women can meet the demands of the new definitions of themselves and their relationships in a relatively positive and adaptive way. The results ...
Date: August 1999
Creator: Hobdy, Juli
Partner: UNT Libraries

Construction of a Physical Map of Moraxella (Branhamella) catarrhalis Strain ATCC25238

Description: In order to gain a better understanding of this microorganismand its role in human pathogenesis, a physical map of Moraxella catarrhalis type strain ATCC25238 was constructed using pulsed field gel electrophoresis (PFGE) in combination with Southern hybridization techniques. Restriction endonucleases Not I, Rsr II, and Sma I were used to digest the chromosomal DNA. An overlapping circular map was generated by cross-hybridization of isolated radiolabeled fragments of Moraxella catarrhalis genomic DNA to dried PFGE gels. The number and location of the 16S and 23S ribosomal RNA genes were determined by digestion with l-Ceul enzyme and by Southern hybridization. Virulence-associated genes, the gene for β-lactamase, and housekeeping genes were also placed onto the physical map.
Date: May 1999
Creator: Nguyen, Kim Thuy
Partner: UNT Libraries

The Relationship Between the Grief Process and the Family System: The Role of Affect, Communication, and Cohesion

Description: Sixty-six people who had recently experienced the death of a parent or a spouse completed a questionnaire packet to assess their current grief symptomatology and some characteristics of the relationships within their family. Participants were asked to fill out a questionnaire 4-5 weeks after the death and then again six months later. The present study compared two competing models to explain whether the grief process affects the characteristics of relationships within the family system or that family characteristics affect the experienced grief symptoms.
Date: August 1999
Creator: Schoka, Elaine
Partner: UNT Libraries

Children and Childhood in Hawthorne's Fiction

Description: This paper explores the role of children and childhood in Nathaniel Hawthorne's fiction. Moreover, it asserts that the child and childhood are keys to a better understanding of Hawthorne's fiction.
Date: August 1999
Creator: Sitz, Shirley Ann Ellis
Partner: UNT Libraries

Assessing Effects of an Environmental Education Field Science Program Fostering Responsibility at an Urban Middle School

Description: The study investigated the ability of an extracurricular program to influence environmental responsibility of sixth and seventh graders. The Children's Environmental Attitude and Knowledge Survey (CHEAKS) was evaluated for appropriateness in assessing the worth of this particular environmental education strategy emphasizing water quality fieldwork and technology. CHEAKS is designed with psychometric reliability and validity that may be used in comparing disparate programs. Wilcoxon two sample tests were used to analyze data gathered from two student groups; one participated in an "Enviro-Mentals Club"; the other received no treatment. Analysis showed no significant change in environmental attitudes between groups, but did show significance (p <= 0.05) in environmental knowledge growth. Therefore, the investigated program had marginal success in influencing environmental responsibility.
Date: May 1999
Creator: Sills, Blake
Partner: UNT Libraries

Contributing Risk Factors in the Association Between Sexual Abuse Experiences and Disturbed Eating Patterns in College Females

Description: This study examined two theoretical factors proposed to explain the relationship between sexual abuse experiences and disturbed eating patterns. Over 300 women completed questionnaires designed to assess sexual abuse histories, bodily shame, body disparagement, and disordered eating behaviors. Multivariate analyses indicated that bodily shame, body image dysphoria, and bodily dissatisfaction were significantly higher in participants with previous sexual violations. In addition, disordered eating symptoms and behaviors were related to reported severity of sexual abuse experiences. However, the relationship between the severity of disturbed eating patterns and sexual abuse histories appears to be more meaningful in relation to the presence of bodily shame and body dissatisfaction, as proposed in previous research. Future research implications are discussed.
Date: August 1999
Creator: Tripp, Margaret Murphy
Partner: UNT Libraries

Authors, Protagonists, and Moral Decision Making in Contemporary Young Adult Realistic Fiction: a Content Analysis

Description: The purpose of this study was to investigate if there is a difference in the way male and female authors of contemporary realistic fiction for young adults portray decision making by their male or female protagonists. Questions asked in the study were: (1) Do female writers of contemporary young adult realistic fiction employ an ethic of justice or an ethic of care for male protagonists involved in moral decision making? (2) Do female writers of contemporary young adult realistic fiction employ an ethic of justice or an ethic of care for female protagonists involved in moral decision making? (3) Do male writers of contemporary young adult realistic fiction employ an ethic of justice or an ethic of care for male protagonists involved in moral decision making? and (4) Do male writers of contemporary young adult realistic fiction employ an ethic of justice or an ethic of care for female protagonists involved in moral decision making? Content analysis was used as the method of collecting data. The sample consisted of 194 novels written from 1989 to 1998, 53 of which contained a moral dilemma. A discussion of the novels included examples of moral dilemmas, alternative solutions, dilemma resolutions, and resolutions based upon care or justice. Analysis of the data revealed: (1) Female writers employ an ethic of care and an ethic of justice for male protagonists involved in moral decision making. (2) Female writers prefer an ethic of care for female protagonists involved in moral decision making. (3) Male writers prefer an ethic of justice for male protagonists involved in moral decision making. (4) Male writers prefer an ethic of justice for female protagonists involved in moral decision making.
Date: August 1999
Creator: Ford, Peggy Kathleen Ollar
Partner: UNT Libraries

Development and Validity of the Teachers' Attitude, Comfort and Training Scale (TACTS) on Sexuality Education

Description: The purpose of the study was to design and validate an instrument designed to investigate teachers' attitudes in regard to adolescent sexuality education. Test development adhered to the guidelines of Aligna and Crocker. Cronbach alpha was performed on the entire instrument and determined the reliability to be .8003, thus the instrument was consistent in measuring the domain areas. A panel of experts assessed content validity of items. A principal component factor analysis and a Pearson's product moment correlation were used for construct validity. Teacher concerns about curriculum implementation, teacher comfort with the subject matter, course-specific teacher attitudes, teacher interest about curriculum content, and teacher attitudes toward sexuality were found to be the constructs of the TACTS.
Date: May 1999
Creator: D'Entremont, Laura S.
Partner: UNT Libraries

Effects of Psychoeducation on Opinions about Mental Illness, Attitudes toward Help Seeking, and Expectations about Psychotherapy

Description: The effect of psychoeducation on opinions about mental illness, attitudes toward help seeking, and expectations about psychotherapy were investigated. One group served as a control, one group read a written lecture on information about mental illness, and one group read a written lecture on information about psychotherapy. The control group, and experimental groups immediately after reading the lecture, completed demographic information, Attitudes Toward Help Seeking-Short Form, Expectations About Counseling-Brief Form, Nunnally Conceptions of Mental Illness Questionnaire, and three College Adjustment Scales (Depression, Anxiety, Self Esteem). Participants were asked to complete the same measures four weeks after the initial assessment. Results: No significant improvement in attitudes toward help seeking was demonstrated in either experimental group, at either time of testing. Expectations about psychotherapy were significantly improved in both experimental groups, which remained significant at Time 2. Opinions about mental illness demonstrated an immediate significant improvement in attitudes with the mental illness lecture group, however this effect did not remain at Time 2. The psychotherapy lecture group did not have significantly improved opinions about mental illness at either time of testing. The control group did not produce any significant changes between Time 1 and Time 2 testing. Experimental group scores demonstrated similarity with those who had previous experience with psychotherapy. No relationship was found between level of adjustment and attitudes toward help seeking, expectations about psychotherapy, or opinions about mental illness at either time of testing.
Date: August 1999
Creator: Gonzalez, Jodi Marie
Partner: UNT Libraries

The Influence of an Interdisciplinary Course on Critical Thinking Skills

Description: The effect of an interdisciplinary algebra/science course on students' critical thinking skills was examined. A traditional college algebra course was used as a comparison group. The students in the sample enrolled in college algebra and then half were randomly placed into the interdisciplinary course. A quasi-experimental pretest-posttest comparison group design was used. The Watson-Glaser Critical Thinking Appraisal was used to measure the students' critical thinking skills. This instrument consists of an overall critical thinking score as well as five subscores in the areas of Inference, Recognition of Assumptions, Deduction, Interpretation and Evaluation of Arguments. It was found that the students in the interdisciplinary course made greater gains in the overall critical thinking score as well as in four of the five subscores. However, the differences in the gains made in the two courses were not statistically significant. Disregarding course, other factors that were found to be closely related to critical thinking were Composite ACT, grade received in the course, Math ACT and grade point average. It was also found that students whose majors were in the Schools of Arts and Letters or Science and Technology scored higher on critical thinking than students whose majors were in the Schools of Business or Education. Factors found to have no relationship to critical thinking were ethnicity, gender and classification.
Date: August 1999
Creator: Elliott, Brett M.
Partner: UNT Libraries

Faculty Identification: Effects on Culture in a Metropolitan Research University

Description: This utilized identification theory to determine if faculty identify with the university and recognize its mission. The study also explored how faculty differentiate between a traditional university and a metropolitan research university. Finally, the study explored whether the faculty consider the University of North Texas to be a Metropolitan Research University. UNT full-time faculty members (N=224) completed questionnaires to indicate their identification with the university and their recognition of the university mission. Analysis showed that faculty have not come to a consensus on the definition of a MRU and that they do not identify with UNT.
Date: May 1999
Creator: Gray, Marlene E.
Partner: UNT Libraries

Countable Additivity, Exhaustivity, and the Structure of Certain Banach Lattices

Description: The notion of uniform countable additivity or uniform absolute continuity is present implicitly in the Lebesgue Dominated Convergence Theorem and explicitly in the Vitali-Hahn-Saks and Nikodym Theorems, respectively. V. M. Dubrovsky studied the connection between uniform countable additivity and uniform absolute continuity in a series of papers, and Bartle, Dunford, and Schwartz established a close relationship between uniform countable additivity in ca(Σ) and operator theory for the classical continuous function spaces C(K). Numerous authors have worked extensively on extending and generalizing the theorems of the preceding authors. Specifically, we mention Bilyeu and Lewis as well as Brooks and Drewnowski, whose efforts molded the direction and focus of this paper. This paper is a study of the techniques used by Bell, Bilyeu, and Lewis in their paper on uniform exhaustivity and Banach lattices to present a Banach lattice version of two important and powerful results in measure theory by Brooks and Drewnowski. In showing that the notions of exhaustivity and continuity take on familiar forms in certain Banach lattices of measures they show that these important measure theory results follow as corollaries of the generalized Banach lattice versions. This work uses their template to generalize results established by Bator, Bilyeu, and Lewis.
Date: August 1999
Creator: Huff, Cheryl Rae
Partner: UNT Libraries

Design of a Monitoring System for a Plasma Cleaning Machine

Description: Plasma cleaning is the most effective dry process to remove surface contaminates from a SAW (Surface Acoustical Wave) device. Consistent gas pressures, flows, and good electrical connections between the chamber shelves are necessary for the process to function predictably. In addition, operation of the monitoring system must be transparent to the plasma cleaning unit. This thesis describes a simple solution to the complex problem of monitoring a plasma cleaning system. The monitoring system uses the LabVIEW® G programming language and hardware, both products of National Instruments, Inc.®, to monitor critical parameters necessary to achieve a consistent process when cleaning these devices.
Date: May 1999
Creator: Fooks, Terry M. (Terry Max)
Partner: UNT Libraries

The Matters of Troy and Thebes and Their Role in a Critique of Courtly Life in Chaucer and the Gawain-Poet

Description: Both Chaucer and the Gawain-poet use the Matters of Troy and Thebes as material for a critique of courtly life, applying these literary matters to the events and actions in and around Ricardian England. They use these classical matters to express concerns about the effectiveness of the court of Richard II. Chaucer uses his earlier works as a testing ground to develop his views about the value of duty over courtly pursuits, ideas discussed more completely in Troilus and Criseyde. The Gawain-poet uses the Matter of Troy coupled with the court of King Arthur to engage in a critique of courtly concerns. The critiques presented by both poets show a tendency toward duty over courtly concerns.
Date: May 1999
Creator: Jones, Oliver M.
Partner: UNT Libraries

Biotic Factors and Temperature Tolerances via Critical Thermal Methodology in Goldfish

Description: CTMinimum and CTMaximum were measured in 620 goldfish to determine if biotic factors, in particular starvation, condition factor and size, affect temperature tolerance. Twenty-eight days of starvation adversely affected both upper and lower temperature tolerance. Condition factor was related to upper but not lower temperature tolerance.
Date: August 1999
Creator: Ford, Tiiu Kirsti, 1972-
Partner: UNT Libraries

The Power Politics of Hells Canyon

Description: This study examines the controversy regarding Hells Canyon on the Snake River, North America's deepest gorge. Throughout the 1950s, federal and private electric power proponents wrangled over who would harness the canyon's potential for generating hydroelectricity. After a decade of debate, the privately-owned Idaho Power Company won the right to build three small dams in the canyon versus one large public power structure. The thesis concludes that private development of Hells Canyon led to incomplete resource development. Further, support of private development led to extensive Republican electoral losses in the Pacific Northwest during the 1950s.
Date: August 1999
Creator: Alford, John Matthew
Partner: UNT Libraries

The Effects of Music Training on Electroencephalographic Coherence of Preschool Children

Description: The purpose of this study was to examine the effects of music training on electroencephalographic (EEG) coherence of preschool children. EEG coherence is a measurement of brain wave activity that reflects anatomical and neurophysiological parameters and functional connectivity between areas of the brain. Participants were 4- to 6-year-old children divided into two groups: one received music training for 20 minutes twice a week for 10 weeks while the other group served as controls. Nineteen channels of EEG data were collected from each child pre- and post-training. Data were collected from three conditions: eyes-open resting, listening to music, and performing the Object Assembly subtest of the Weschler Preschool and Primary Scale of Intelligence - Revised (1989). The hypothesis was that the music training group would show increased EEG coherence as compared to controls. The EEG data was reduced into seven bandwidths and analyzed separately for each condition. Multiple ANCOVAs were used to factor out pre-test variability and to maximize connectivity changes between the two groups. The dependent measures were the post-QEEG electrode pairs and the covariates were the pre-QEEG electrode pairs. Results indicated the eyes-open and listening to music conditions showed more significant changes between the groups than the Object Assembly condition. Overall, each condition showed increased connectivity for the music training group versus controls. The eyes-open condition differentiated children with and without music training during a resting condition, and showed similar patterns as those identified by other researchers comparing musicians versus nonmusicians. The listening to music condition identified connections including a topographical pattern of auditory analysis, increased working memory activation, increased activity between musically sensitive areas, and increased interhemispheric activity. Findings with the Object Assembly condition were not as robust as expected. However, patterns of increased connectivity associated with visuospatial processing were found with the music training group.
Date: August 1999
Creator: DeBeus, Roger J. (Roger John)
Partner: UNT Libraries

A Reduced Grid Method for a Parallel Global Ocean General Circulation Model

Description: A limitation of many explicit finite-difference global climate models is the timestep restriction caused by the decrease in cell size associated with the convergence of meridians near the poles. A computational grid in which the number of cells in the longitudinal direction is reduced toward high-latitudes, keeping the longitudinal width of the resulting cells as uniform as possible and increasing the allowable timestep, is applied to a three-dimensional primitive equation ocean-climate model. This ''reduced'' grid consists of subgrids which interact at interfaces along their northern and southern boundaries, where the resolution changes by a factor of three. Algorithms are developed to extend the finite difference techniques to this interface, focusing on the conservation required to perform long time integrations, while preserving the staggered spatial arrangement of variables and the numerics used on subgrids. The reduced grid eliminates the common alternative of filtering high-frequency modes from the solution at high-latitudes to allow a larger timestep and reduces execution time per model step by roughly 20 percent. The reduced grid model is implemented for parallel computer architectures with two-dimensional domain decomposition and message passing, with speedup results comparable to those of the original model. Both idealized and realistic model runs are presented to show the effect of the interface numerics on the model solution. First, a rectangular, mid-latitude, at-bottomed basin with vertical walls at the boundaries is driven only by surface wind stress to compare three resolutions of the standard grid to reduced grid cases which use various interface conditions. Next, a similar basin with wind stress, heat, and fresh water forcing is used to compare the results of a reduced grid with those of a standard grid result while exercising the full set of model equations. Finally, global model runs, with topography, forcing, and physical parameters similar to those used for ...
Date: December 1, 1999
Creator: Wickett, M.E.
Partner: UNT Libraries Government Documents Department

Development and evaluation of high resolution quadrupole mass analyzer and an inductively coupled plasma-Mach disk

Description: By definition a plasma is an electrically conducting gaseous mixture containing a significant concentration of cations and electrons. The Inductively Coupled Plasma (ICP) is an electrodeless discharge in a gas at atmospheric pressure. This discharge is an excellent one for vaporizing, atomizing, and ionizing elements. The early development of the ICP began in 1942 by Babat and then by Reed in the early 1960s. This was then followed by the pioneering work of Fassel and coworkers in the late 1960s. Commercial ICP spectrometers were introduced in the mid 1970s. A major breakthrough in the area of ICP took place in the early 1980s when the ICP was shown to be an excellent ion source for mass spectrometry.
Date: December 10, 1999
Creator: Amad, Ma'an Hazem
Partner: UNT Libraries Government Documents Department

An Evaluation of Unsaturated Flow Models in an Arid Climate

Description: The objective of this study was to evaluate the effectiveness of two unsaturated flow models in arid regions. The area selected for the study was the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site in Nye County, Nevada. The two models selected for this evaluation were HYDRUS-1D [Simunek et al., 1998] and the SHAW model [Flerchinger and Saxton, 1989]. Approximately 5 years of soil-water and atmospheric data collected from an instrumented weighing lysimeter site near the RWMS were used for building the models with actual initial and boundary conditions representative of the site. Physical processes affecting the site and model performance were explored. Model performance was based on a detailed sensitivity analysis and ultimately on storage comparisons. During the process of developing descriptive model input, procedures for converting hydraulic parameters for each model were explored. In addition, the compilation of atmospheric data collected at the site became a useful tool for developing predictive functions for future studies. The final model results were used to evaluate the capacities of the HYDRUS and SHAW models for predicting soil-moisture movement and variable surface phenomena for bare soil conditions in the arid vadose zone. The development of calibrated models along with the atmospheric and soil data collected at the site provide useful information for predicting future site performance at the RWMS.
Date: December 1, 1999
Creator: Dixon, J.
Partner: UNT Libraries Government Documents Department

Transport processes in directional solidification and their effects on microstructure development

Description: The processing of materials with unique electronic, mechanical, optical and thermal properties plays a crucial role in modern technology. The quality of these materials depend strongly on the microstructure and the solute/dopant fields in the solid product, that are strongly influenced by the intricate coupling of heat and mass transfer and melt flow in the growth systems. An integrated research program is developed that include precisely characterized experiments and detailed physical and numerical modeling of the complex transport and dynamical processes. Direct numerical simulation of the solidification process is carried out that takes into account the unsteady thermo-solutal convection in the vertical Bridgman crystal growth system, and accurately models the thermal interaction between the furnace and the ampoule by appropriately using experimentally measured thermal profiles. The flow instabilities and transitions and the nonlinear evolution following the transitions are investigated by time series and flow pattern analysis. A range of complex dynamical behavior is predicted with increasing thermal Rayleigh number. The route to chaos appears as: steady convection {r_arrow} transient mono-periodic {r_arrow} transient bi-periodic {r_arrow} transient quasi-periodic {r_arrow} transient intermittent oscillation-relaxation {r_arrow} stable intermittent oscillation-relaxation attractor. The spatio-temporal dynamics of the melt flow is found to be directly related to the spatial patterns observed experimentally in the solidified crystals. The application of the model to two phase Sn-Cd peritectic alloys showed that a new class of tree-like oscillating microstructure develops in the solid phase due to unsteady thermo-solutal convection in the liquid melt. These oscillating layered structures can give the illusion of band structures on a plane of polish. The model is applied to single phase solidification in the Al-Cu and Pb-Sn systems to characterize the effect of convection on the macroscopic shape and disorder in the primary arm spacing of the cellular/dendritic freezing front. The apparently puzzling experimental observation of ...
Date: November 8, 1999
Creator: Mazumder, Prantik
Partner: UNT Libraries Government Documents Department

Anisotropic magnetization and transport properties of RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm)

Description: This study of the RAgSb{sub 2} series of compounds arose as part of an investigation of rare earth intermetallic compounds containing antimony with the rare earth in a position with tetragonal point symmetry. Materials with the rare earth in a position with tetragonal point symmetry frequently manifest strong anisotropies and rich complexity in the magnetic properties, and yet are simple enough to analyze. Antimony containing intermetallic compounds commonly possess low carrier densities and have only recently been the subject of study. Large single grain crystals were grown of the RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm) series of compounds out of a high temperature solution. This method of crystal growth, commonly known as flux growth is a versatile method which takes advantage of the decreasing solubility of the target compound with decreasing temperature. Overall, the results of the crystal growth were impressive with the synthesis of single crystals of LaAgSb{sub 2} approaching one gram. However, the sample yield diminishes as the rare earth elements become smaller and heavier. Consequently, no crystals could be grown with R=Yb or Lu. Furthermore, EuAgSb{sub 2} could not be synthesized, likely due to the divalency of the Eu ion. For most of the RAgSb{sub 2} compounds, strong magnetic anisotropies are created by the crystal electric field splitting of the Hund's rule ground state. This splitting confines the local moments to lie in the basal plane (easy plane) for the majority of the members of the series. Exceptions to this include ErAgSb{sub 2} and TmAgSb{sub 2}, which have moments along the c-axis (easy axis) and CeAgSb{sub 2}, which at intermediate temperatures has an easy plane, but exchange coupling at low temperatures is anisotropic with an easy axis. Additional anisotropy is also observed within the basal plane of DyAgSb{sub 2}, where the moments are restricted to align along ...
Date: November 8, 1999
Creator: Myers, Kenneth D.
Partner: UNT Libraries Government Documents Department

Wave propagation in ordered, disordered, and nonlinear photonic band gap materials

Description: Photonic band gap materials are artificial dielectric structures that give the promise of molding and controlling the flow of optical light the same way semiconductors mold and control the electric current flow. In this dissertation the author studied two areas of photonic band gap materials. The first area is focused on the properties of one-dimensional PBG materials doped with Kerr-type nonlinear material, while, the second area is focused on the mechanisms responsible for the gap formation as well as other properties of two-dimensional PBG materials. He first studied, in Chapter 2, the general adequacy of an approximate structure model in which the nonlinearity is assumed to be concentrated in equally-spaced very thin layers, or 6-functions, while the rest of the space is linear. This model had been used before, but its range of validity and the physical reasons for its limitations were not quite clear yet. He performed an extensive examination of many aspects of the model's nonlinear response and comparison against more realistic models with finite-width nonlinear layers, and found that the d-function model is quite adequate, capturing the essential features in the transmission characteristics. The author found one exception, coming from the deficiency of processing a rigid bottom band edge, i.e. the upper edge of the gaps is always independent of the refraction index contrast. This causes the model to miss-predict that there are no soliton solutions for a positive Kerr-coefficient, something known to be untrue.
Date: December 10, 1999
Creator: Lidorikis, Elefterios
Partner: UNT Libraries Government Documents Department