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Development of derived investigation levels for use in internal dosimetry at the West Valley Demonstration Project
The objective was to determine if the routine intemal dosimetry program at the West Valley Demonstration Project is capable of meeting the performance objective of 1 mSv annual effective dose equivalent due to internal contamination. With the use of the computer code REMedy the annual effective dose equivalent is calculated. Some of the radionuclides of concern result in an annual effective dose equivalent that exceeds the performance objective. Although the results exceed the performance objective, in all but two cases they do not exceed the US DOE regulatory limits. In these instances the Th-232 and Am-241 were determined to exceed the committed dose equivalent limit to their limiting tissue. In order to document the potential missed dose for regulatory compliance, Sr-90 is used as an indicator for Th-232. For Am-241 an investigation as to whether or not the minimum detectable amount can be lowered is performed. The derived investigation levels as a result of this project are 4.9E3 Bq/lung count for Co-60, 2.2E4 Bq/lung count for Cs-137, 1.9 Bq/1 for Sr-90 and for radionuclides other than Sr-90 any value greater than or equal to three standard deviations above their net count is considered to require further investigation.
Date:
1991
Creator:
Johnson, Paul
System:
The UNT Digital Library
Evaluation of Self-Perception in ACHD Children
Only a limited amount of research exists which addresses low self-esteem, poor self-concept, and distorted self-image in ADHD children. The most urgent task is to test assumptions regarding self-perception and to assess the dimensions of self-concept of ADHD children. The Self-Perception Profile for Children (Harter, 1985) was used in the proposed study to assess those dimensions. Subjects of this study are 8- to 12- year-old boys diagnosed with ADHD and the same age boys who exhibit no symptoms of psychopathology. Results of analyses of covariance indicate that ADHD boys tend to view themselves as significantly less competent in the areas of scholastic competence and global self-worth in comparison to their normal counterparts. Differences between means of ADHD and normal boys on the social acceptance subscale of the SPPC approached significance. Intelligence and social status also had a significant impact on some of the differences noted between the two groups.
Date:
1991
Creator:
Walters, Pace Jill
System:
The UNT Digital Library
Music and Patronage in Milan 1535-1550 and Vincenzo Ruffo's First Motet Book
The present study reconstructs the musical milieu in which Vincenzo Ruffo's 1542 motet collection was conceived through an examination of the archival materials surviving from each of the major musical establishments known to be active in Milan 1535-1550. The relationship of the 1542 collection to Milanese musical activity. Its publication problems and its current position in source studies are then explored in light of the archival information that is currently available.
Date:
1991
Creator:
Getz, Christine Suzanne, 1957-
System:
The UNT Digital Library
A High-Brightness Thermionic Microwave Electron Gun
In a collaborative effort by SSRL, AET Associates, and Varian Associates, a high-brightness microwave electron gun using a thermionic cathode has been designed, built, tested, and installed for use with the SSRL 150 MeV linear accelerator. This thesis discusses the physics behind the design and operation of the gun and associated systems, presenting predictions and experimental tests of the gun`s performance. The microwave gun concept is of increasing interest due to its promise of providing higher-current, lower-emittance electron beams than possible from conventional, DC gun technology. In a DC guns, accelerating gradients are less than 8 MV/m, while those in a microwave gun can exceed 100 MV/m, providing much more rapid initial acceleration, thereby reducing the deleterious effects of space-charge. Microwave guns produce higher momentum beams than DC guns, thus lessening space-charge effects during subsequent beam transport. Typical DC guns produce kinetic energies of 80--400 KeV, compared to 2--3 MeV for the SSRL microwave gun. ``State-of-the-art`` microwave gun designs employ laser-driven photocathodes, providing excellent performance but with greater complexity and monetary costs. A thermionic microwave gun with a magnetic bunching system is comparable in cost and complexity to a conventional system, but provides performance that is orders of magnitude better. …
Date:
February 1991
Creator:
Borland, Michael
System:
The UNT Digital Library
Sue Bridehead As a Model for Modern Feminism
Thesis written by a student in the UNT Honors College discussing the growth of feminist characters in literature, especially Sue Bridehead from Thomas Hardy's novel, Jude the Obscure.
Date:
Spring 1991
Creator:
Milam, Pamela
System:
The UNT Digital Library
The application of psoralens to the study of DNA structure, function and dynamics
A series of six nitroxide spin-labeled psoralens were designed, synthesized and tested as probes for DNA dynamics. The synthesis of these spin-labeled psoralen derivatives and their photoreactivity with double-stranded DNA fragments is described. The spin labels (nitroxides) were demonstrated to survive the uv irradiation required to bind the probe to the target DNA. EPR spectra of the photobound spin-labels indicate that they do not wobble with respect to the DNA on the time-scales investigated. The author has used psoralen modified DNA as a model for the study of DNA repair enzyme systems in human cell free extracts. He has shown that damage-induced DNA synthesis is associated with removal of psoralen adducts and therefore is {open_quotes}repair synthesis{close_quotes} and not an aberrant DNA synthesis reaction potentiated by deformation of the DNA by adducts. He has found that all DNA synthesis induced by psoralen monoadducts is the consequence of removal of these adducts. By the same approach he has obtained evidence that this in vitro system is capable of removing psoralen cross-links as well. Reported here are synthetic methods that make use of high intensity lasers coupled with HPLC purification to make homogeneous and very pure micromole quantities of furan-side monoadducted, cross-linked, and …
Date:
April 1, 1991
Creator:
Spielmann, P. H.
System:
The UNT Digital Library
Electromagnetic dissociation of {sup 238}U in heavy-ion collisions at 120 MeV/A
This thesis describes a measurement of the heavy-ion induced electromagnetic dissociation of a 120 MeV/A {sup 238}U beam incident on five targets: {sup 9}Be, {sup 27}Al, {sup nat}Cu, {sup nat}Ag, and {sup nat}U. Electromagnetic dissociation at this beam energy is essentially a two step process involving the excitation of a giant resonance followed by particle decay. At 120 MeV/A there is predicted to be a significant contribution of the giant quadrupole resonance to the EMD cross sections. The specific exit channel which was looked at was projectile fission. The two fission fragments were detected in coincidence by an array of solid-state {Delta}E-E detectors, allowing the changes of the fragments to be determined to within {plus_minus} .5 units. The events were sorted on the basis of the sums of the fragments` charges, acceptance corrections were applied, and total cross sections for the most peripheral events were determined. Electromagnetic fission at the beam energy of this experiment always leads to a true charge sum of 92. Due to the imperfect resolution of the detectors, charge sums of 91 and 93 were included in order to account for all of the electromagnetic fission events. The experimentally observed cross sections are due to nuclear …
Date:
April 1, 1991
Creator:
Justice, M. L.
System:
The UNT Digital Library
Mental Status, Intellectual, and Mood States Associated with Environmental Illness Patients
The purpose of the present study was to begin development of a psychological profile for environmentally ill patients. Existing psychiatric labels are unable to encompass these patients. Test scores were drawn from a pool of 89 patients whose environmental exposures were verified by the presence of toxins in the blood serum. A Mental Status Exam, a Wechsler Adult Intelligence Scale-Revised screen, and the Profile of Mood States were administered. Results indicate a primary pattern which is significantly different from test norms consisting of fatigue, reduced mental functioning, and a lack of psychotic or personality disorder indicators. The reported symptoms of environmentally ill patients were objectively verified by current psychological test instruments. The need for a new diagnostic category for people who have been poisoned by environmental toxins is discussed.
Date:
April 1991
Creator:
Fincher, Cynthia Ellen
System:
The UNT Digital Library
Small catalytic RNA: Structure, function and application
We have utilized a combination of photochemical cross-linking techniques and site-directed mutagenesis to obtain secondary and tertiary structure information for the self-cleaving, self-ligating subsequence of RNA from the negative strand of Satellite Tobacco Ringspot Virus. We have found that the helical regions fold about a hinge to promoting four different possible tertiary interactions, creating a molecular of similar shape to a paperclip. A model suggesting that the ``paperclip`` and ``hammerhead`` RNAs share a similar three dimensional structure is proposed. We have used a self-cleaving RNA molecule related to a subsequence of plant viroids, a ``hammerhead,`` to study the length-dependent folding of RNA produced during transcription by RNA polymerase. We have used this method to determine the length of RNA sequestered within elongating E. coli and T7 RNA polymerase complexes. The data show that for E. coli RNA polymerase 12{plus_minus}1 nucleotides are sequestered within the ternary complex, which is consistent with the presence of an RNA-DNA hybrid within the transcription bubble, as proposed by others. The result for T7 RNA polymerase differs from E. coli RNA polymerase, with only 10{plus_minus}1 nucleotides sequestered within the ternary complex, setting a new upper limit for the minimum RNA-DNA required for a stable elongating complex. …
Date:
April 1, 1991
Creator:
Monforte, J. A.
System:
The UNT Digital Library
Classical Inspiration and Modern Expression: Greek Art Turned Fauve, Constructivist, Dada, and Pop
Senior colloquium written by a student in the UNT Honors College discussing Greek sculpture and architecture as filtered through the Fauve, Constructivist, Dada, and Pop artistic movements. The author takes examples of Grecian sculpture, recreates them in each of the other styles, and discusses the results.
Date:
April 27, 1991
Creator:
Capen, Sheri
System:
The UNT Digital Library
Adlerian Life-Style, Social Interest, and Job Satisfaction Among Catholic Priests
The purpose of this study was to seek an understanding of the problem of low morale among Catholic priests based on the principles of Individual Psychology. The relationship of Adlerian life-style and social interest to job satisfaction among 210 pastors randomly selected from 13 of the 14 Catholic dioceses in Texas was investigated. The Life-style Personality Inventory (LSPI) was used to measure the Adlerian life-style. The Social Interest Scale (SIS) was used to measure the Adlerian concept of social interest. The Job Descriptive Index (JDI) was used to measure job satisfaction.
Date:
May 1991
Creator:
Ugwokaegbe, Paul U. (Paul Ugochukwu)
System:
The UNT Digital Library
AIDS and Higher Education in Texas: Policies at Accredited Institutions
This study of all of the post secondary institutions accredited by the Commission on Colleges of the Southern Association of Colleges and Schools which were located in Texas determined the number that had policies regarding persons with AIDS. The study determined how long policies had been in effect and analyzed policies in order to determine commonalities and differences. An additional purpose was to examine relationships between five major variables and 18 topics which were identified as being issues likely to be addressed in institutional AIDS policies.
Date:
May 1991
Creator:
Gunn, Paul W. (Paul Wayne)
System:
The UNT Digital Library
An analysis of absenteeism cases taken to arbitration: factors used by arbitrators in the decision-making process
The purpose of this study was to examine factors used by arbitrators in deciding the outcome of disciplinary labor arbitration cases involving excessive employee absenteeism. The seven key tests of just cause identified by Carroll Daugherty in the 1966 Enterprise Wire Co. arbitration case were used as the basis for examining the cases in the study.
Date:
May 1991
Creator:
Clay, Joan Marie
System:
The UNT Digital Library
An Analysis of Refuse Derived Fuel as an Environmentally Acceptable Fuel Alternative for the Cement Industry
Resource recovery is an attractive alternative to the waste disposal problem. The chief by-product of this process, refuse derived fuel (RDF) can be co-fired in traditional coal burning facilities. The cement industry is a potential user of RDF. This study, based on a test burn done at Texas Industries Inc. in Midlothian, Texas, demonstrated the technical, environmental, and economic feasibility of using RDF fuel in a cement kiln. Technically, the cement showed no deleterious effects when RDF was substituted for coal/natural gas at 20% by Btu content. Environmentally, acid rain gases were reduced. Economically, RDF was shown to be a cost effective fuel substitute if a resource recovery facility was erected on site.
Date:
May 1991
Creator:
Brooks, Cheryl L. (Cheryl Leigh)
System:
The UNT Digital Library
An Analysis of the Information Content of Bond-Rating Changes: A Case of Differential Information
This dissertation examines the reaction of common stock prices to the announcement of changes in bond ratings by Moody's Bond Service, while having a control for differential information availability. The Institutional Brokers Estimate System (I/B/E/S) number of security analysts and coefficient of variation of earning per share (EPS) estimates are used as a proxy for information availability of the firms. Past studies differs in their conclusions as to whether the market has responded to announcement of bond rating changes. None of past studies have controlled for differential information availability. This study, using daily stock returns data and the event study methodology with the statistical test, finds that while the sample of rating downgrades exhibit significantly negative abnormal price effect during the announcement period, the magnitude of this effect is significantly higher for firms with low information availability. For the rating upgrades, the sample as a whole has no abnormal announcement period returns, but the sample of firms with lower information earns significantly positive abnormal returns. This study provides support for the hypothesis that the announcement effect of bond-rating changes is conditional on the information available about the firm.
Date:
May 1991
Creator:
Pongspaibool, Nantaphol
System:
The UNT Digital Library
An Analysis of the Utilization of the Work Measurement System Requirements of Military Standard 1567a as Compared to Standard Operating Procedures
Work measurement systems are widely used by American manufacturers in establishing labor standards as inputs for budgeting, estimating, planning, evaluating, and managing production. These systems are used by defense related and non-defense related contractors alike. However in 1987, their use was required in United States Air Force major procurement contracts through Military Standard 1567A.
Date:
May 1991
Creator:
Ekholm, Harry H. (Harry Hilding)
System:
The UNT Digital Library
Attitudes of Nursing Faculty Toward Patients With AIDS and Patients With a Homosexual Lifestyle
The purposes of this study were (1) to determine whether patients with AIDS are stigmatized by nursing faculty, (2) to determine whether practicing homosexuals are stigmatized by nursing faculty, (3) to determine whether faculty attitudes toward AIDS patients are influenced by the patients' sexual preference, and (4) to determine whether faculty attitudes toward practicing homosexual patients are influenced by the patients' disease. This study is a modified replication of studies by Kelly et al.
Date:
May 1991
Creator:
Reynolds, Carol A. (Carol Ann)
System:
The UNT Digital Library
Brain-Reactive Antibodies: Molecular Specificity and Relationship to Biological Aging
Brain-reactive antibodies (BRA) increase in frequency with age in several mammalian species and may be involved in the pathogenesis of age-related dementia. In this experiment, the molecular specificity of BRA in mouse sera was determined using an immunoblot assay, and the relationship of BRA to longevity was studied by comparing the rate of formation of specific BRAs in diet restricted C57BL/6NNia, B6D2F1/NNia, and DBA/2NNia, genotypes which differ markedly in life-span.
Date:
May 1991
Creator:
Apte, Vaijayanti
System:
The UNT Digital Library
The cadenza: performance practice in alto trombone concerti of the eighteenth century
This study examines the history of the cadenza, as well as the fundamental elements of a good cadenza. This paper is intended to help the modern trombonist learn to create appropriate, original cadenzas for classical trombone concerti. Both historical and modern writing,as well as extant classical cadenzas are used as a guide.
Date:
May 1991
Creator:
Bruenger, David
System:
The UNT Digital Library
The Cantatas of Jean-Philippe Rameau
By the early eighteenth century, French music was tangibly influenced by the Italian style which had already permeated much of Europe. The French Cantata is symptomatic of that often disparaged influx. The cantatas of Rameau are a significant contribution to an important form. Written almost entirely in the early years of the artist's career, they hold details of his stylistic development. In the present study of Rameau's cantatas several aspects of his style are discussed as they relate both to his theoretic writings and to the various influences of the time. Examples of those stylistic elements found in the cantatas are cited and discussed. There is, as well, a comparison of the works to the poetic form standardized by Rousseau.
Date:
May 1991
Creator:
McManus, Catherine
System:
The UNT Digital Library
Capacitance of edge plane of pyrolytic graphite in acetonitrile solutions
The capacitance of the edge plane of pyrolytic graphite electrodes, in acetonitrile solutions, is measured by recording the current response to an applied triangular voltage sweep; TVS, and then fitting the current response with an appropriate function, (via a set of adjustable parameters). The pretreatment of the electrodes, the supporting electrolyte concentration used, and the frequency of the input TVS, were all found to affect the measured capacitance. In these experiments, a background current was also seen and the shape of the current output for the TVS; the charging/discharging curve, is shown to correlate with the magnitude of this background current. In addition, the size of the background current was found to have some dependence on the type of electrode pretreatment procedure used. 60 refs., 49 figs., 3 tabs.
Date:
May 1, 1991
Creator:
Minick, S. K. & Ishida, Takanobu
System:
The UNT Digital Library
Cellular Biomarkers for Measuring Toxicity of Xenobiotics: Effects of PCBs on Earthworm Lumbricus Terrestris Coelomocytes
The research presented herein provides information on coelomocyte (leukocyte) collection, function and immunotoxicity from polychlorinated biphenyls (PCB) in the earthworm Lumbricus terrestris. Research was undertaken as part of an overall goal to develop a well-documented and scientifically valid non-mammalian surrogate immunoassay with the earthworm Lumbricus terrestris to assess immunotoxic potential of xenobiotics. The principal objectives were to: (1) Develop an extrusion model for analyzing immunotoxicity of xenobiotics; (2) determine if coelomocytes can be collected repeatedly without obvious harm to the earthworm or change in immune response of the coelomocytes harvested and (3) validate the response sensitivity profiles of a panel of biomarkers {differential and total cell counts, erythrocyte rosette (ER) and secretory rosette (SR) formation with, and phagocytosis of antigenic rabbit red blood cells} in earthworms after acute exposure to a known mammalian and L. terrestris immunotoxin, the PCB Aroclor 1254.
Date:
May 1991
Creator:
Eyambe, George Sona
System:
The UNT Digital Library
Chemical Ionization (CI) GC/MS Analysis of Underivatized Amphetamines Followed by Chiral Derivatization to Identify d and l-Isomers with Ion Trap Mass Spectrometry
An efficient two step procedure has been developed using CI GC/MS for analyzing amphetamines and related compounds. The first step allows the analysis of underivatized amphetamines with the necessary sensitivity and specificity to give spectral identification, including differentiation between methamphetamine and phentermine. The second step involves preparing a chiral derivative of the extract to identify d and 1-isomeric composition.
Date:
May 1991
Creator:
Tarver, John A. (John Arthur)
System:
The UNT Digital Library
Circulatory and Respiratory Responses to Cycle Ergometry at Different Pedal Rates
The effects of moderate workload exercise at different pedal rates on circulatory and respiratory parameters were studied. Five subjects performed seven discontinuous constant-load cycle ergometer tests of 30 minutes duration at pedal rates of 40, 50, 60, 70, 80, 90 and 100 rpm. Oxygen uptake and carbon dioxide production were determined by standard open circuit spirometry, while heart rate was recorded by electrocardiograph. The CO₂ rebreathing procedure was administered during the exercise bout in order to determine cardiac output. Blood pressure was determined for each test, and total peripheral resistance was calculated. The findings indicate that progressive increases in pedal frequency during discontinuous constant-load cycle ergometry produce progressive increases in cardiovascular, respiratory and metabolic responses and a decrease in gross exercise mechanical efficiency. The results indicate that oxygen uptake, cardiac output, heart rate, ventilation and arterial-venous oxygen difference increases curvilinearly as pedal rate increases, possibly as a result of increases in recruitment of muscle fibers and/or muscle groups. These findings suggest that circulatory and respiratory responses are due to "central command" which sets the basic efferent response pattern. However, this effector pattern is modulated by afferent input originating from the legs during progressive increases in pedal rate.
Date:
May 1991
Creator:
Hernandez, Raymundo
System:
The UNT Digital Library