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O-Acetylserine Sulhydralase-A from Salmonella typhimurium LT-2: Thermodynamic Properties and SPectral Identification of Intermediates

Description: O-Acetylserine Sulfhydrylase (OASS) is a pyridoxal phosphate enzyme that catalyzes the reaction of O-acetyl-Lserine with sulfide to give L-cysteine. OASS is present as two isoforms, designated -A and -B. The kinetic mechanism of OASS-A is well known and there is also much known concerning the acid-base chemistry of the enzyme. However, little is known concerning the location of the rate determining steps, the sequencing of chemical steps that occur at the active site, or the nature of the rate determining transition states. The studies performed to help elucidate these aspects of the OASS-A mechanism included determination of the thermodynamics of both half reactions, along with studies utilizing substrate analogs of OAS halting the reaction at specific points along the reaction pathway allowing the identification of reaction intermediates. The free energy change of the first half reaction was shown to be -5.7 Kcal/mole while the second half reaction was shown to be, for all intents and purposes, irreversible. Intermediates along the reaction pathway that have been previously identified include the internal Schiff base and the a-aminoacrylate. The external Schiff base was identified using the analogs cysteine, alanine, and glycine while the geminal diamine was identified using the analog serine. Formation of the external aldimine was shown to be pH dependent with a pK of 8.1 ± 0.3 most likely representing a general base that accepts a proton from the a-amine of cysteine to facilitate a nucleophilic attack on C4r of the PLP imine. Formation of the geminal diamine was also shown to be pH dependent with two pK values having an average value of 8.1. One of the groups most likely represents the general base which accepts a proton from the a-amine of cysteine while the second group likely interacts with the amino acid side chain to orientate the amino acid ...
Date: August 1993
Creator: Simmons, James Walter
Partner: UNT Libraries

A Theoretical Network Model and the Incremental Hypercube-Based Networks

Description: The study of multicomputer interconnection networks is an important area of research in parallel processing. We introduce vertex-symmetric Hamming-group graphs as a model to design a wide variety of network topologies including the hypercube network.
Date: May 1995
Creator: Mao, Ai-sheng
Partner: UNT Libraries

A Study of the Literature Pertaining to the Areas of Health Education, Physical Education, and Recreation that is Available to Students and Faculty Members in the Class B, A, and AA Senior High Schools of Texas

Description: The investigator made a study of the literature pertaining to the areas of health education, physical education and recreation that is available to students and to faculty members in the class B, A, and AA senior high school libraries of Texas during the school year 1949-1950.
Date: 1950
Creator: Smith, Anna
Partner: UNT Libraries

A Study of How Business Education Conferences Can Promote Better Business Education in the State of Texas

Description: This is a study of business education conferences in Texas made in an effort to improve business training in Texas secondary schools. Many young people leave high school intending to enter the business world. Business is ready to accept those who are competent. The educational preparation of students, however, is often insufficient to permit their seizing the opportunities offered to them.
Date: 1950
Creator: Smith, Woodie McConnell
Partner: UNT Libraries

A Beginning Program of Vocational Guidance through the Commercial Department of Sweetwater High School

Description: The purpose of this thesis is to present a beginning program of vocational guidance through the commercial department of the small high school. Guidance, whether in the field of personality, education, health, financial, or occupational guidance, must be developed over a period of months and years. This study will deal only with the personnel, activities, and materials needed to introduce such a vocational guidance program.
Date: 1950
Creator: Sivells, Leila Mae
Partner: UNT Libraries

The Present Practices of School Business Managers in the Schools of Texas

Description: The purpose of this study is to determine the present practices with respect to business managers in the school systems of Texas. This study attempts to determine from present practices what the business manager's duties and qualifications are; what the scholastic population of a school should be in order to employ a business manager; what the relationship of the business manager to the superintendent and the school board is; what experience and training the business managers have had; what the salaries of business managers are; what the trends in the employment of business managers are; and from what fields business managers are drawn.
Date: 1950
Creator: Sivells, C. Graves, Jr.
Partner: UNT Libraries

Orality-Literacy Theory and the Victorian Sermon

Description: In this study, I expand the scope of the scholarship that Walter Ong and others have done in orality-literacy relations to examine the often uneasy juxtaposition of the oral and written traditions in the literature of the Victorian pulpit. I begin by examining the intersections of the oral and written traditions found in both the theory and the practice of Victorian preaching. I discuss the prominent place of the sermon within both the print and oral cultures of Victorian Britain; argue that the sermon's status as both oration and essay places it in the genre of "oral literature"; and analyze the debate over the extent to which writing should be employed in the preparation and delivery of sermons.
Date: May 1995
Creator: Ellison, Robert H. (Robert Howard)
Partner: UNT Libraries

The Effect of Auditor Knowledge on Information Processing during Analytical Review

Description: Auditors form judgments by integrating the evidence they gather with information stored in memory (knowledge). As they acquire experience, auditors have the opportunity to learn how different patterns of evidence are associated with particular audit problems. Research in experimental psychology has demonstrated that individuals with task-specific experience can match the cues they encounter with patterns they have learned, and form judgments without consciously analyzing the individual cues. Accounting researchers have suggested that auditors develop judgment templates through task-specific experience, and that these knowledge structures automatically provide decisions in familiar situations. I examined whether auditor knowledge leads to reliance on judgment templates. To test this thesis, I synthesized a theoretical framework and developed research hypotheses that predict relationships between task-specific experience (my surrogate for knowledge) and (1) measures of cognitive effort, (2) accuracy of residual memory traces, and (3) performance with respect to identifying potential problems. To test these predictions, I provided senior auditors with comprehensive case materials for a hypothetical client and asked them to use analytical procedures to identify potential audit problems. Subjects acquired information and documented their findings on personal computers using software that I developed to record their activities.
Date: February 1995
Creator: O'Donnell, Ed
Partner: UNT Libraries

A Measurement of the Popularity of the Extra-Curricular Activities in Cleburne High School, Cleburne, Texas, with the Relationships of Certain Factors to that Popularity

Description: The purposes of this study are: (1) to determine the popularity of extra-curricular organizations existing in the school as a means of indicating the successful and the unsuccessful groups in the school, (2) to establish the relationships of certain factors to the popularity of the activities so that efforts may be made to improve less successful activities, (3) to discover the extent and the popularity of social activities provided by the city of Cleburne, Texas, for the high school students in order that administrators of the school may have more insight into the extent of the need of high school students for social activities sponsored by the school.
Date: 1950
Creator: Watson, Katie Maxine
Partner: UNT Libraries

Some Effects of Color on Personnel in Industry

Description: The problem of this study is to determine some effects of color on personnel in industry. Consideration is given to management-employee relationship, employee's physical and mental health, and the resulting increase of both quality and quantity of production.
Date: 1950
Creator: Wages, Morris L.
Partner: UNT Libraries

A Comparative Study of the Scholastic Achievement of Junior High School Boys Who Work after School and Those Who Do Not

Description: In this particular study the problem is to determine the influence working after school hours has upon a group of junior high school boys. This study is concerned with comparisons in subject matter achievement, self and social adjustment, and behavior records and ratings. It is the purpose of this study to make these comparisons with boys who work after school and those who do not.
Date: 1950
Creator: Trusty, Ruby
Partner: UNT Libraries

John Christopher Stevens: a Study of his Presidential Administration at Abilene Christian University Abilene, Texas, 1969-1981

Description: The purpose of this study is to examine historically the presidential administration of John Christopher Stevens at Abilene Christian University from 1969 to 1981. During this time the institution grew in enrollment, faculty, facilities, endowment, and quality of educational opportunity. Limited to selected experiences and accomplishments, this dissertation examines Stevens' personal and administrative characteristics through interviews with him and those who worked with him. Materials were also used from Stevens' Presidential Archives in the Callie Faye Milliken Special Collections of the Herman and Margaret Brown Library at Abilene Christian University.
Date: December 1994
Creator: Roach, James Kenneth, 1935-
Partner: UNT Libraries

A Comparative Analysis of Adopted Textbooks in Social Studies in Texas from 1913 to 1949

Description: The purpose of this study is to make a comparative analysis of the adopted textbooks for the sixth and seventh grades in social studies in the public schools of Texas from 1913 until the present time, 1949, to determine changes in concepts of presenting and teaching social studies during this time.
Date: 1950
Creator: Thompson, Mary Alice
Partner: UNT Libraries

Relationships Between Physical Skills and Total Adjustment of Junior High School Boys

Description: The problem in this study is to show the possible relationship between improved physical skills and the total adjustment of boys at the junior high school level. A limited number of boys selected from the seventh and eighth grades who were without adequate physical skills were given special assistance for improving such skills, and a record was kept of the procedure and possible results of this instructional program.
Date: 1950
Creator: Taylor, William Richard
Partner: UNT Libraries

A Study of Dropouts in the Secondary Schools of Port Arthur, Texas

Description: The purpose of this study was to investigate the problem of dropouts or withdrawals among the pupils of the secondary schools of Port Arthur, Texas. It was hoped that some significant information could be compiled as to the reasons why such students in this particular city leave school before high-school graduation, and that academic, environmental, and personal factors might be identified in their relationship to the causation of dropouts or withdrawals.
Date: 1951
Creator: Arrington, Electa Carol
Partner: UNT Libraries

An Evaluation of the Gilmer-Aikin Law as to Its Soundness Financially and Administratively

Description: The problem of this study is to determine the soundness of the Gilmer-Aikin Law financially and administratively. No attempt will be made to apply the principles of the law to any particular area or school district, but the law will be considered as a whole as it will apply to the schools of Texas in general.
Date: 1950
Creator: Whitaker, Ernest B.
Partner: UNT Libraries

A Survey of Supervisory Practices to Determine the Extent to Which they Meet Recommended Practices and Procedures

Description: The purpose of this study is to make an investigation of the qualifications and supervisory practices of a selected number of supervisors in counties, cities, and special subjects, to determine the extent to which they meet recommended practices and procedures in supervision. Attention is directed to the types of supervisors, to training and experience, to planning the supervisory program, to methods of facilitating teacher growth, to methods of improving instruction, and to methods of evaluating instruction.
Date: 1950
Creator: Widtfeldt, Ruby Richards
Partner: UNT Libraries

An Analytical Study of the Physical Education Program for Junior and Senior High School Girls in Fort Worth, Texas with Recommendations for Future Cooperative Program Development in Physical Education in the Two School Levels

Description: The purpose of the study was to determine the relationship between the girls' physical education programs in the junior and senior high schools in the Fort Worth Public Schools and to determine to what extent these programs insure the complete development of the girl, physically, mentally and socially in the two school levels.
Date: 1950
Creator: White, Mary Nell
Partner: UNT Libraries