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Caregivers' Appraisal of Alzheimer's Disease Symptoms and the Relationship to Decisions About Care (open access)

Caregivers' Appraisal of Alzheimer's Disease Symptoms and the Relationship to Decisions About Care

The purpose of the present study was to compare 42 community-dwelling spouse and child Alzheimer's Disease caregivers with 38 community-dwelling potential caregivers on salience of illness symptoms, and accuracy of judging symptoms of illnesses.
Date: May 1994
Creator: Jones, Phyllis L. (Phyllis Lee)
System: The UNT Digital Library
Effect of the Home Environment on Children's 10 Scores and the Influence of Family Socioeconomic Status (open access)

Effect of the Home Environment on Children's 10 Scores and the Influence of Family Socioeconomic Status

Contributions of home environment and family socioeconomic status (SES) on the intelligence test performance of 24 exceptional children aged five through seven years were investigated. It was hypothesized that higher SES would enrich the children's environment providing a more stimulating learning experience, and would reflect a positive correlation with measures of the home environment. Additional hypotheses were that both HOME scores and SES scales would show a positive correlation with intelligence test performance. The positive association found between SES and HOME Inventory scores suggests that families with a higher SES have the ability to direct more resources toward their children. However, according to the present study, this does not affect the intelligence test performance of exceptional children.
Date: May 1994
Creator: Singer, David D.
System: The UNT Digital Library
The Sublime and the Beautiful in the Works of Claude-Joseph Vernet (open access)

The Sublime and the Beautiful in the Works of Claude-Joseph Vernet

This thesis examines the roles of the sublime and the beautiful in the works of eighteenth-century French landscape painter Claude-Joseph Vernet. An introduction to the study, a history of the sublime and beautiful, and an overview of the way these ideas are portrayed in Vernet's calm and storm pendants are provided. How commissions for these pendants relate to theoretical developments of the sublime and beautiful and how Vernet became aware of the these ideas are addressed. The thesis shows Vernet was not dependent on British patrons or on the century's most influential aesthetic treatise on the sublime and the beautiful by Edmund Burke, because Vernet started painting such themes well before Burke's treatise (1757) and did so in response to French patrons.
Date: May 1994
Creator: Howard, Jane
System: The UNT Digital Library
The Cohomology for the Nil Radical of a Complex Semisimple Lie Algebra (open access)

The Cohomology for the Nil Radical of a Complex Semisimple Lie Algebra

Let g be a complex semisimple Lie algebra, Vλ an irreducible g-module with high weight λ, pI a standard parabolic subalgebra of g with Levi factor £I and nil radical nI, and H*(nI, Vλ) the cohomology group of Λn'I ⊗Vλ. We describe the decomposition of H*(nI, Vλ) into irreducible £1-modules.
Date: May 1994
Creator: Sawyer, Cameron C. (Cameron Cunningham)
System: The UNT Digital Library
Reliability of a Graded Exercise Test During Deep Water Running and Comparison of Peak Metabolic Responses to Treadmill Running (open access)

Reliability of a Graded Exercise Test During Deep Water Running and Comparison of Peak Metabolic Responses to Treadmill Running

Populations that utilize deep water running (DWR) are described in Chapter I. A review of the literature concerning maximal and submaximal responses during DWR, shallow water running and swimming is presented in Chapter II. The protocols to elicit maximal responses during DWR and treadmill running (TMR), subject characteristics, and statistical methods employed are described in Chapter III. The results, presented in Chapter IV, indicate that the DWR protocol is a reliable test for eliciting peak oxygen consumption and heart rate. Furthermore, the metabolic responses during DWR are lower than TMR. Chapter V discusses factors which might limit maximal responses during DWR. Chapter VI contains suggestions for further research. Raw data are presented in Appendix A.
Date: May 1994
Creator: Mercer, John A. (John Andrew)
System: The UNT Digital Library
Natural Grammar: a Painless Way to Teach Grammar in the Secondary Language Arts Classroom (open access)

Natural Grammar: a Painless Way to Teach Grammar in the Secondary Language Arts Classroom

Natural Grammar provides a way for the junior high or high school English teacher to draw upon students' "natural," or subconscious, knowledge of the systems and structures of spoken English. When such subconscious knowledge is conceptualized (brought to the conscious level), the students can transfer that knowledge to their writing. Natural grammar, in other words, allows the teacher to begin with what students already know, so that he or she may help students to build upon that knowledge in the context of the students' own writing. Chapters include a brief history of grammar instruction, a synopsis of the theories that contributed to the development of natural grammar, a description of natural grammar, and suggestions for implementation of natural grammar in the classroom.
Date: May 1994
Creator: Scott, Leslie A. (Leslie Ann)
System: The UNT Digital Library
Effect of Small Group Incentives on Sales Productivity in Two Retail Shops: A Case Study (open access)

Effect of Small Group Incentives on Sales Productivity in Two Retail Shops: A Case Study

To meet global competition many companies have reorganized work process systems, eliminated management levels, formed employee work groups and implemented variable compensation systems. This study investigated the effect of group incentives on individual sales performance in two specialty shops located in a large metropolitan hotel. Two questions were addressed: What effect would adding a group bonus plan have on individual employee's sales performance who had previously received hourly wages in one shop; and, what effect would changing an individual incentive plan to a group plan have on the individual employee's sales performance in the other shop. In one shop 5 of 7 employees' productivity increased: in the other, 1 of 3 subjects' productivity increased. Contingencies in both shops are analyzed and suggestions offered for future research.
Date: May 1994
Creator: Bohrer, Kathleen
System: The UNT Digital Library
The Effects of a Performance Improvement Strategy in a Work Team Setting: a Case Study (open access)

The Effects of a Performance Improvement Strategy in a Work Team Setting: a Case Study

A popular approach to operating organizations in the 1990s is the implementation of work teams. The current literature offers little information on the use of performance management techniques in work team settings. This case study examined the effects of employing a performance improvement strategy on employee performance in a work team environment comprised of part-time graduate students. The performance improvement strategy included composing job descriptions, job aids (e.g., work organization charts), task request logs and posting weekly and monthly performance feedback. Improvements were observed in some aspects of team performance. Some of the improvement was due to task clarification and improved scheduling produced by the antecedent interventions. Performance feedback had little effect on measured performance but seemed to facilitate discussion and problem-solving.
Date: May 1994
Creator: McHale, Carrie L. (Carrie Lynn)
System: The UNT Digital Library
Reflective masks for extreme ultraviolet lithography (open access)

Reflective masks for extreme ultraviolet lithography

Extreme ultraviolet lithographic masks are made by patterning multilayer reflective coatings with high normal incidence reflectivity. Masks can be patterned by depositing a patterned absorber layer above the coating or by etching the pattern directly into the coating itself. Electromagnetic simulations showed that absorber-overlayer masks have superior imaging characteristics over etched masks (less sensitive to incident angles and pattern profiles). In an EUVL absorber overlayer mask, defects can occur in the mask substrate, reflective coating, and absorber pattern. Electromagnetic simulations showed that substrate defects cause the most severe image degradation. A printability study of substrate defects for absorber overlayer masks showed that printability of 25 nm high substrate defects are comparable to defects in optical lithography. Simulations also indicated that the manner in which the defects are covered by multilayer reflective coatings can affect printability. Coverage profiles that result in large lateral spreading of defect geometries amplify the printability of the defects by increasing their effective sizes. Coverage profiles of Mo/Si coatings deposited above defects were studied by atomic force microscopy and TEM. Results showed that lateral spread of defect geometry is proportional to height. Undercut at defect also increases the lateral spread. Reductions in defect heights were observed for …
Date: May 1, 1994
Creator: Nguyen, Khanh Bao
System: The UNT Digital Library
Dynamic NMR studies of restricted arene rotation in the chromiu tricarbonyl thiophene and selenophene complexes (open access)

Dynamic NMR studies of restricted arene rotation in the chromiu tricarbonyl thiophene and selenophene complexes

This thesis contains the results of organometallic studies of thiophene and selenophene coordination in transition metal complexes. Chromium tricarbonyl complexes of thiophene, selenophene, and their alkyl-substituted derivatives were prepared and variable-temperature {sup 13}C NMR spectra of these complexes were recorded in dimethyl ether. Bandshape analyses of these spectra yielded activation parameters for restricted rotation of the thiophene and selenophene ligands in these complexes. Extended Hueckel molecular orbital calculations (EHMO) of the free thiophene and selenophene ligands and selected chromium tricarbonyl thiophene complexes were performed to better explain the activation barriers of these complexes. The structure of Cr(CO){sub 3}({eta}{sup 5}-2,5-dimethylthiophene) was established by a single crystal X-ray diffraction study.
Date: May 27, 1994
Creator: Sanger, M. J.
System: The UNT Digital Library
The design and performance of a twenty barrel hydrogen pellet injector for Alcator C-Mod (open access)

The design and performance of a twenty barrel hydrogen pellet injector for Alcator C-Mod

A twenty barrel hydrogen pellet injector has been designed, built and tested both in the laboratory and on the Alcator C-Mod Tokamak at MIT. The injector functions by firing pellets of frozen hydrogen or deuterium deep into the plasma discharge for the purpose of fueling the plasma, modifying the density profile and increasing the global energy confinement time. The design goals of the injector are: (1) Operational flexibility, (2) High reliability, (3) Remote operation with minimal maintenance. These requirements have lead to a single stage, pipe gun design with twenty barrels. Pellets are formed by in- situ condensation of the fuel gas, thus avoiding moving parts at cryogenic temperatures. The injector is the first to dispense with the need for cryogenic fluids and instead uses a closed cycle refrigerator to cool the thermal system components. The twenty barrels of the injector produce pellets of four different size groups and allow for a high degree of flexibility in fueling experiments. Operation of the injector is under PLC control allowing for remote operation, interlocked safety features and automated pellet manufacturing. The injector has been extrusively tested and shown to produce pellets reliably with velocities up to 1400 m/sec. During the period from …
Date: May 1, 1994
Creator: Urbahn, J. A.
System: The UNT Digital Library
Photodissociation and photoionization of organosulfur radicals (open access)

Photodissociation and photoionization of organosulfur radicals

The dynamics of S({sup 3}P{sub 2,1,0}, {sup 1}D{sub 2}) production from the 193 nm photodissociation of CH{sub 3}SCH{sub 3}, H{sub 2}S and CH{sub 3}SH have been studied using 2 + 1 resonance-enhanced multiphoton ionization (REMPI) techniques. The 193 nm photodissociation cross sections for the formation of S from CH{sub 3}S and HS initially prepared in the photodissociation of CH{sub 3}SCH{sub 3} and H{sub 2}S are estimated to be 1 {times} 10{sup {minus}18} and 1.1 {times} 10{sup {minus}18} cm{sup 2}, respectively. The dominant product from CH{sub 3}S is S({sup 1}D), while that from SH is S({sup 3}P). Possible potential energy surfaces involved in the 193 nm photodissociation of CH{sub 3}S({tilde X}) and SH(X) have been also examined. Threshold photoelectron (PE) spectra for SH and CH{sub 3}S formed in the ultraviolet photodissociation of H{sub 2}S and CH{sub 3}SH, respectively, have been measured using the nonresonant two-photon pulsed field ionization (N2P-PFI) technique. The rotationally resolved N2P-PFI-PE spectrum obtained for SH indicates that photoionization dynamics favors the rotational angular momentum change {Delta}N < 0 with the {Delta}N value up to {minus}3, an observation similar to that found in the PFI-PE spectra of OH (OD) and NO. The ionization energies for SH(X{sup 2}{product}{sub 3,2}) and …
Date: May 27, 1994
Creator: Hsu, Chia-Wei
System: The UNT Digital Library
Bridging the pressure gap: In situ atomic-level investigations of model platinum catalyst surfaces under reaction conditions by scanning tunneling microscopy (open access)

Bridging the pressure gap: In situ atomic-level investigations of model platinum catalyst surfaces under reaction conditions by scanning tunneling microscopy

Results of this thesis show that STM measurements can provide information about the surfaces and their adsorbates. Stability of Pt(110) under high pressures of H2, O2, and CO was studied (Chap. 4). In situ UHV and high vacuum experiments were carried out for sulfur on Pt(111) (Chap.5). STM studies of CO/S/Pt(111) in high CO pressures showed that the Pt substrate undergoes a stacking-fault-domain reconstruction involving periodic transitions from fcc to hcp stacking of top-layer atoms (Chap.6). In Chap.7, the stability of propylene on Pt(111) and the decomposition products were studied in situ with the HPSTM. Finally, in Chap.8, results are presented which show how the Pt tip of the HPSTM was used to locally rehydrogenate and oxidize carbonaceous clusters deposited on the Pt(111) surface; the Pt tip acted as a catalyst after activation by short voltage pulses.
Date: May 1, 1994
Creator: McIntyre, B. J.
System: The UNT Digital Library
High order harmonic generation in rare gases (open access)

High order harmonic generation in rare gases

The process of high order harmonic generation in atomic gases has shown great promise as a method of generating extremely short wavelength radiation, extending far into the extreme ultraviolet (XUV). The process is conceptually simple. A very intense laser pulse (I {approximately}10{sup 13}-10{sup 14} W/cm{sup 2}) is focused into a dense ({approximately}10{sup l7} particles/cm{sup 3}) atomic medium, causing the atoms to become polarized. These atomic dipoles are then coherently driven by the laser field and begin to radiate at odd harmonics of the laser field. This dissertation is a study of both the physical mechanism of harmonic generation as well as its development as a source of coherent XUV radiation. Recently, a semiclassical theory has been proposed which provides a simple, intuitive description of harmonic generation. In this picture the process is treated in two steps. The atom ionizes via tunneling after which its classical motion in the laser field is studied. Electron trajectories which return to the vicinity of the nucleus may recombine and emit a harmonic photon, while those which do not return will ionize. An experiment was performed to test the validity of this model wherein the trajectory of the electron as it orbits the nucleus or …
Date: May 1, 1994
Creator: Budil, Kimberly Susan
System: The UNT Digital Library
Art and Self-Awareness: A Personal Investigation (open access)

Art and Self-Awareness: A Personal Investigation

This paper describes the artist's conception of their scientific knowledge and spiritual beliefs, and the juxtaposition of the two in a single awareness. Michael Muller discusses the use of printmaking, drawing, and photo mechanical processes to represent this awareness through visual imagery, and includes photographs of the works.
Date: May 1994
Creator: Muller, Michael
System: The UNT Digital Library
Secret Schemes: Frequently There Must Be a Beverage (open access)

Secret Schemes: Frequently There Must Be a Beverage

Secret Schemes is a collection of four short stories and three chapters of a novel; all the stories are humorous and deal with young women and their struggles in romantic relationships.
Date: May 1994
Creator: Phillips, Laura Rachel
System: The UNT Digital Library
Te Deum (open access)

Te Deum

Te Deum is a single movement work for chorus and orchestra. It employs an ensemble comprising the complement of string, woodwind, and brass instruments typically available in a small symphony orchestra with an expanded percussion section. The choral forces are in proportional relation to the instrumental forces are in proportional relation to the instrumental forces and it is sung in the original Latin. The intended performance time is approximately 18 minutes. Temporal aspects of the work are characterized by three contrasting sections. The slow and solemn opening section is given to long stretches of silence sparsely punctuated by low drums. The remainder of the work is texturally more dense and employs a much quicker tempo. A steady core pulse is also a key feature, with attention given to avoiding any regular metrical implications by use offset accents, non-consecutive identical phrase lengths, and a slow harmonic rhythm.
Date: May 1994
Creator: Piekarski, James
System: The UNT Digital Library
Multigrid methods with applications to reservoir simulation (open access)

Multigrid methods with applications to reservoir simulation

Multigrid methods are studied for solving elliptic partial differential equations. Focus is on parallel multigrid methods and their use for reservoir simulation. Multicolor Fourier analysis is used to analyze the behavior of standard multigrid methods for problems in one and two dimensions. Relation between multicolor and standard Fourier analysis is established. Multiple coarse grid methods for solving model problems in 1 and 2 dimensions are considered; at each coarse grid level we use more than one coarse grid to improve convergence. For a given Dirichlet problem, a related extended problem is first constructed; a purification procedure can be used to obtain Moore-Penrose solutions of the singular systems encountered. For solving anisotropic equations, semicoarsening and line smoothing techniques are used with multiple coarse grid methods to improve convergence. Two-level convergence factors are estimated using multicolor. In the case where each operator has the same stencil on each grid point on one level, exact multilevel convergence factors can be obtained. For solving partial differential equations with discontinuous coefficients, interpolation and restriction operators should include information about the equation coefficients. Matrix-dependent interpolation and restriction operators based on the Schur complement can be used in nonsymmetric cases. A semicoarsening multigrid solver with these operators …
Date: May 1, 1994
Creator: Xiao, Shengyou
System: The UNT Digital Library
Application of a passive electrochemical noise technique to localized corrosion of candidate radioactive waste container materials (open access)

Application of a passive electrochemical noise technique to localized corrosion of candidate radioactive waste container materials

One of the key engineered barriers in the design of the proposed Yucca Mountain repository is the waste canister that encapsulates the spent fuel elements. Current candidate metals for the canisters to be emplaced at Yucca Mountain include cast iron, carbon steel, Incoloy 825 and titanium code-12. This project was designed to evaluate passive electrochemical noise techniques for measuring pitting and corrosion characteristics of candidate materials under prototypical repository conditions. Experimental techniques were also developed and optimized for measurements in a radiation environment. These techniques provide a new method for understanding material response to environmental effects (i.e., gamma radiation, temperature, solution chemistry) through the measurement of electrochemical noise generated during the corrosion of the metal surface. In addition, because of the passive nature of the measurement the technique could offer a means of in-situ monitoring of barrier performance.
Date: May 1, 1994
Creator: Korzan, M. A.
System: The UNT Digital Library
Variable angle correlation spectroscopy (open access)

Variable angle correlation spectroscopy

In this dissertation, a novel nuclear magnetic resonance (NMR) technique, variable angle correlation spectroscopy (VACSY) is described and demonstrated with {sup 13}C nuclei in rapidly rotating samples. These experiments focus on one of the basic problems in solid state NMR: how to extract the wealth of information contained in the anisotropic component of the NMR signal while still maintaining spectral resolution. Analysis of the anisotropic spectral patterns from poly-crystalline systems reveal information concerning molecular structure and dynamics, yet in all but the simplest of systems, the overlap of spectral patterns from chemically distinct sites renders the spectral analysis difficult if not impossible. One solution to this problem is to perform multi-dimensional experiments where the high-resolution, isotropic spectrum in one dimension is correlated with the anisotropic spectral patterns in the other dimensions. The VACSY technique incorporates the angle between the spinner axis and the static magnetic field as an experimental parameter that may be incremented during the course of the experiment to help correlate the isotropic and anisotropic components of the spectrum. The two-dimensional version of the VACSY experiments is used to extract the chemical shift anisotropy tensor values from multi-site organic molecules, study molecular dynamics in the intermediate time regime, …
Date: May 1, 1994
Creator: Lee, Y. K.
System: The UNT Digital Library
A Natural History (open access)

A Natural History

A Natural History is a collection of original poetry written over the past three years. This project represents a period of learning and growth, as well as a concentrated effort to develop an individual writing style and voice grounded in the most enduring poetic values of the past.
Date: May 1994
Creator: Pipes, Todd David
System: The UNT Digital Library
Caregiver Personality as a Contributing Factor in Caregiver Burden (open access)

Caregiver Personality as a Contributing Factor in Caregiver Burden

Personality characteristics of spousal and adult children and active potential caregivers of persons with Alzheimer's Disease were studied in order to better predict caregiver burden and aspects of well-being. Contrary to prediction, no differences were found between spouse and adult children active caregivers on measures of well-being. Additionally, adult children potential caregivers indicated feeling less control over their lives than spouse potential caregivers. When social desirability was controlled, active caregivers reported greater fluctuations in affect than did potential caregivers. As predicted, personality characteristics of individuals were found to have the biggest role in determining which individuals experience stress or burden.
Date: May 1994
Creator: Anderson, Cristina L. (Cristina Lee)
System: The UNT Digital Library
Determination of toxic material penetrations for wildland respirator filters (open access)

Determination of toxic material penetrations for wildland respirator filters

Thousands of wildland firefighters are exposed to high levels of toxic materials every year. Carbon monoxide, formaldehyde and acrolein gases, along with high particulate concentrations, are the major toxics encountered. Currently, the only respiratory protection wildland firefighters use is a bandanna over the mouth and nose. In this study, a modem activated carbon cartridge with an electrostatic prefilter was compared to a typical bandanna for its ability to filter wildland smoke toxics such as formaldehyde and particulates. The results of the tests were disappointing; neither filter performed very well. The activated carbon cartridge and prefilter efficiently collected formaldehyde gas for up to 60 minutes; however, it only collected 85 percent of the challenge particulate. ]Me bandanna, as expected, was only partially effective at collecting smoke particulate and filtered no toxic gases.
Date: May 1, 1994
Creator: Foote, Kenneth Lawrence
System: The UNT Digital Library
A Study of the Processing Properties of Hard-Particle Reinforced Composite Solders (open access)

A Study of the Processing Properties of Hard-Particle Reinforced Composite Solders

The microstructural, mechanical and thermal properties of various composite solder formulations were investigated. Special interest was given in observing the processing properties, microstructural characteristics, fatigue behavior, tensile strength, and the effect of environmental ageing on the composite solder formulations. The solderability parameters wetting and speed of soldering, reflow temperature, and the thermal stability of the resulting composite solder were also examined.
Date: May 1994
Creator: Calderon, Jose Guadalupe
System: The UNT Digital Library