Degree Level

Accounting for Human Resources: Implications for Theory and Practice. (open access)

Accounting for Human Resources: Implications for Theory and Practice.

Knowledge workers are an important resource for the typical modern business firm, yet financial reporting ignores such resources. Some researchers contend that the accounting profession has stressed reliability in order to make the accounting appear objective. Others concur, noting that accounting is an insecure profession and adopts strict rules when faced with uncertainty. Accountants have promulgated a strict rule to expense human resource costs, although many know that such resources have future benefits. Some researchers suggest that any discipline must modify its language in order to initiate change toward providing useful social ameliorations. If accounting theorists extend this idea to the accounting lexicon.s description of investments in human resources, investors and other accounting user groups might gain greater insight into how a firm fosters and nourishes human capital. I tested three hypotheses related to this issue by administering an experiment designed to assess financial analysts. perceptions about alternative financial statement treatments of human resources in an investment recommendation task. I predicted that (1) analysts' perceptions of the reliability (relevance) of the information they received would decrease (increase) as the treatment of human resources increasingly violated GAAP (became more current-oriented), (2) analysts exposed to alternative accounting treatments would report a lower …
Date: December 2001
Creator: Stovall, Olin Scott
System: The UNT Digital Library
An Analysis of Sales People's Perceptions of Performance Appraisal Criteria at a Telecommunications Corporation. (open access)

An Analysis of Sales People's Perceptions of Performance Appraisal Criteria at a Telecommunications Corporation.

The purpose of this study was to identify and analyze sales people's perceptions of performance appraisal criteria in a telecommunications corporation. The study was prompted by the perceived disillusionment of the sales people with the current performance appraisal criteria. The perceptions of 67 sales people were assessed using a questionnaire developed by the researcher. One-way analysis of variance procedures (ANOVA) were used to determine if there were statistically significant differences in premise and telemarketing sales people's perceptions of performance appraisal criteria. Findings indicated that there were no statistically significant difference in premise and telemarketing sales people's perceptions of the 38 performance appraisal criteria statements. Findings did not indicate a statistically significant difference in premise and telemarketing sales people's perceptions of the performance criteria statements, the attitude or satisfaction statements, and the peripheral issue statements. Based on this study, the sales people appear to have clear perceptions of the performance appraisal criteria.
Date: December 2001
Creator: Harris, Ellen L.
System: The UNT Digital Library
Attitudes of American and Korean Early Childhood Educators Regarding Programs for Gifted/Talented Young Children. (open access)

Attitudes of American and Korean Early Childhood Educators Regarding Programs for Gifted/Talented Young Children.

The purpose of this research was to study the attitudes of Korean and American early childhood educators concerning gifted children and programs aimed specifically at meeting their needs. The study examined general attitudes towards giftedness and gifted education programs and factors that might affect those attitudes. The study also examined desirable environments for young gifted children. Twenty-item questionnaires were developed and logically divided into six sections (identification, teacher environment, classroom environment, parent environment, educational rights, and program). A systematic process of development, analysis, and refinement of the questionnaire was done. The questionnaires were given randomly to American educators attending the 1996 National Association for the Education of Young Children (NAEYC) conference. A random Korean sample included early childhood educators listed in the Korean Association for Early Childhood Education Directory (1995-1996) and the Korean Association for Child Care Directory (1995-1996). All subjects were members of one of three groups: (a) teacher educators, (b) teachers, and (c) administrators/directors. The surveys found agreement between Korean and American early childhood educators on the importance of knowing the strengths of individual gifted children, the need to stimulate higher order thinking skills, the rights of gifted children to an appropriate education, a perception of more work …
Date: December 2001
Creator: Song, Kyu-Woon
System: The UNT Digital Library
The Characteristics of Teacher-Directed Modeling Evidenced in the Practices of Three Experienced High School Choral Directors. (open access)

The Characteristics of Teacher-Directed Modeling Evidenced in the Practices of Three Experienced High School Choral Directors.

The purpose of this study was to analyze the characteristics of teacher directed modeling evidenced in the practices of three experienced high school choral directors. Research questions were: 1. What modeling activities were exhibited in each teacher's rehearsals? 2. When viewing a 45-minute composite tape of each teacher's instructional activities representative of all rehearsals, what instructional behaviors did each choral director recognize and identify as modeling? 3. What instructional episodes on the composite tape not identified by the teachers contained elements of modeling? 4. What other episodes from the remainder of each choral director's rehearsal practice contributed to an understanding of modeling? Videotapes of three high school choral directors were recorded over the course of one semester. Excerpts from rehearsals were combined to form a 45-minute composite tape of each choral director. A text transcription was made of the composite tape. Participant directors viewed their tape and identified instructional episodes that they recognized as examples of modeling. Identifications were analyzed, and descriptive categories of modeling behaviors were established. Modeling was found to be a teacher generated or delegated act of demonstration. Demonstrations were musical or non-musical and belonging to either of three distinct categories: audible, visible, or process modeling. Subdivisions …
Date: December 2001
Creator: Grimland, Fredna H.
System: The UNT Digital Library
Combat Reconsidered: A Statistical Analysis of Small-Unit Actions During the American Civil War (open access)

Combat Reconsidered: A Statistical Analysis of Small-Unit Actions During the American Civil War

Historians often emphasize the physical features of battleterrain, weaponry, troop formations, earthworks, etc.in assessments of Civil War combat. Most scholars agree that these external combat conditions strongly influenced battle performance. Other historians accentuate the ways in which the mental stresses of soldiering affected combat performance. These scholars tend to agree that fighting effectiveness was influenced by such non-physical combat conditions as unit cohesion, leadership, morale, and emotional stress. Few authors argue that combat's mental influences were more significant in determining success or failure than the physical features of the battlefield. Statistical analysis of the 465 tactical engagements fought by twenty-seven Federal regiments in the First Division of the Army of the Potomac's Second Corps throughout the American Civil War suggests that the mental aspects of battle affected fighting efficiency at least as muchand probably more thancombat's physical characteristics. In other words, the soldiers' attitudes, opinions, and emotions had a somewhat stronger impact on combat performance than their actions, positions, and weaponry.
Date: December 2001
Creator: Barloon, Mark C.
System: The UNT Digital Library

Comparative Morphology of Sensilla Styloconica on the Proboscis of North American Nymphalidae and Other Selected Taxa: Systematic and Ecological Considerations.

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Sensilla styloconica on the proboscis of 107 species of North American and tropical butterflies were comparatively studied using the scanning electron microscope. Focus was on 76 species of North American Nymphalidae representing 45 genera and 11 subfamilies. Nomenclature for generalized and specific types of nymphalid sensilla is proposed. Written descriptions and micrographs are presented for each species studied. Morphological features were generally consistent for all or most species within genera and sometimes within subfamilies, with specified exceptions. Statistical analysis revealed significant differences for six of eight variables tested between two distinct feeding guilds of North American Nymphalidae. Average number, density, extent of proboscis coverage with sensilla, their total length, and shoulder spine length were all significantly greater in the non-nectar feeding guild than in nectar feeders, and may indicate adaptation for greater efficiency in feeding on flat surfaces. The greater frequency of apical shoulder spines in non-nectar feeders may represent adaptation for protection of sensory pegs from mechanical abrasion during feeding, or for anchoring the flexible proboscis tip to the surface. Correlation analysis revealed 9 out of 28 positive correlations in nectar feeders and 5 out of 28 in non-nectar feeders. Results of preliminary cladistic analysis were not considered to …
Date: December 2001
Creator: Petr, Daniel
System: The UNT Digital Library
Death and Ethnicity: A Psychocultural Study-Twenty-Five Years Later. (open access)

Death and Ethnicity: A Psychocultural Study-Twenty-Five Years Later.

his study compares ethnic, age, and gender differences concerning attitudes and behaviors toward death, dying, and bereavement among Caucasian, African, Hispanic, and Asian American adult participants in north Texas with the results of a 1976 study by Kalish and Reynolds on death attitudes and behaviors of Caucasian, African, Mexican, and Japanese American adult participants in Los Angeles, California. A modified version of Kalish and Reynolds' study questionnaire was administered to 526 respondents (164 Caucasian, 100 African, 205 Hispanic, and 57 Asian Americans) recruited from community and church groups. Findings of this study were compared with those of Kalish and Reynolds in specific areas, including experience with death, attitudes toward one's own death, dying, and afterlife, and attitudes toward the dying, death, or grief of someone else. Data was analyzed employing the same statistical tools as those used by Kalish and Reynolds, i.e., chi square calculations, frequencies, percentages, averages, and analyses of variance. As compared with the earlier study, results indicated that this study's participants were less likely to have known as many persons who had died recently or to state they would try very hard to control grief emotions in public. Present study participants were more likely to have visited …
Date: December 2001
Creator: Peveto, Cynthia A.
System: The UNT Digital Library
A Descriptive Study of Accredited Counseling Programs. (open access)

A Descriptive Study of Accredited Counseling Programs.

The Council for Accreditation of Counseling and Related Education Programs (CACREP) is the accrediting body for the field of counselor education. Since the inception of the standards, several individuals have published journal articles reviewing the strengths and weaknesses of CACREP accreditation. The purpose of this study was to do a preliminary survey of the opinions of individuals within CACREP accredited programs to discover the effects of accreditation on programs. The survey of opinions from respondent CACREP accredited programs indicated interesting results. The eleven frequently held beliefs about improvements after accreditation was substantiated by the number, the percentage, and the Chi Square results from respondent programs. Therefore, after CACREP accreditation, most programs reported the opinion that: students have higher grade point averages and test scores; students are younger, learn better, and receive more employment opportunities; a higher percentage of students pass the licensed professional counselor examination; average scores are higher on the nationally certified counselor examination; programs receive more applicants and faculty is more professionally active, publishes more, and presents more. The second part of the survey indicated that a large percentage of respondent programs offer courses beyond the CACREP core curriculum experiences (91%) and that a variety of courses are …
Date: December 2001
Creator: Brew, Leah
System: The UNT Digital Library
An E-government Readiness Model (open access)

An E-government Readiness Model

The purpose of this study is to develop an e-government readiness model and to test this model. Consistent with this model several instruments, IS assessment (ISA), IT governance (ITG), and Organization-IS alignment (IS-ALIGN) are examined for their ability to measure the readiness of one organization for e-government and to test the instruments fit in the proposed e-government model. The ISA instrument used is the result of adapting and combining the IS-SERVQUAL instrument proposed by Van Dyke, Kappelman, and Pybutok (1997), and the IS-SUCCESS instrument developed by Kappelman and Chong (2001) for the City of Denton (COD) project at UNT. The IS Success Model was first proposed by DeLone and McLean (1992), but they did not validate this model. The ITG instrument was based on the goals of the COD project for IT governance and was developed by Sanchez and Kappelman (2001) from UNT. The ISALIGN instrument was also developed by Sanchez and Kappelman (2001) for the COD project. It is an instrument based on the Malcolm Baldrige National Quality Award (MBNQA) that measures how effectively a government organization utilizes IT to support its various objectives. The EGOV instrument was adapted from the study of the Action-Audience Model developed by Koh …
Date: December 2001
Creator: Liu, Shin-Ping
System: The UNT Digital Library
Effect of Individualized Curricular Accommodations, Incorporating Student Interest and the Impact on the Motivation and Occurrence/ Nonoccurrence of Disruptive Behavior Displayed By Students with Emotional/behavioral Disorders. (open access)

Effect of Individualized Curricular Accommodations, Incorporating Student Interest and the Impact on the Motivation and Occurrence/ Nonoccurrence of Disruptive Behavior Displayed By Students with Emotional/behavioral Disorders.

As a result of the reauthorization of the Individuals with Disabilities Education Act of 1997, schools must now consider positive behavioral interventions and strategies to address problem behavior of students with Emotional/Behavioral Disorders (E/BD). Given the poor behavioral, academic, and social outcomes for these students, there is a compelling need to identify effective, proactive interventions. Current literature has well established the ineffectiveness of traditional, punitive, and consequence-laden strategies to deal with behaviors. Research has shown the manipulation of antecedent stimuli, in the form of curricular adaptations, can provide a positive, proactive means of managing behavior. Specifically, curriculum modifications, based on student interest, are proposed as a positive, proactive strategy used to manipulate antecedent stimuli to improve the behavior of students with E/BD. The purpose of this study was to investigate the manipulation of antecedent stimuli through the implementation of individualized, curricular adaptations, based on student interest, to reduce the problem behavior of students exhibiting disruptive behaviors. A second purpose was to explore the effect of those adaptations on the behavior motivation of students with E/BD. In this study, curriculum modifications based on student interest were used to reduce disruptive behavior, increase desirable behavior, and effect change in the motivation for …
Date: December 2001
Creator: Teaff, Teresa L.
System: The UNT Digital Library
Effects of Teaching Reading Through Discussion of Text Structures. (open access)

Effects of Teaching Reading Through Discussion of Text Structures.

The purpose of this study was to investigate the effectiveness of teaching reading through discussion of text structures on students' reading comprehension. The design of the study was a Pretest-Posttest Control-Group Design. One hundred twenty-six sophomore and senior Thai college students majoring in English and attending afternoon English classes participated in the 10-week study and were randomly assigned to an experimental group and a control group. The experimental group received reading instruction in the characteristics of narrative and expository text structures and how to discuss the details of story by applying knowledge of text structures. The control group, on the other hand, read each story silently by themselves and answered comprehension questions. The posttest means of the two groups were compared, and a t test was used to test the significance difference of the means. The results did not reveal any differences between the means. The short time of the intervention may be a crucial factor that made the two strategies yield the same effects. However, the survey responses showed the participants liked reading through discussion of text structures more than reading by themselves.
Date: December 2001
Creator: Piyanukool, Surachai
System: The UNT Digital Library

The Effects of Web-Based Learning Versus Traditional Instructor-Based Learning on Student Knowledge and Satisfaction Based on Student Learning Styles

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The purpose of this study was to compare the effects of Web-based learning (WBL) versus those of traditional instructor-based learning (IBL) on student knowledge and satisfaction based on student learning styles. Other goals were to determine if WBL is more effective for those with a particular learning style. The study examined a sample of undergraduate students who were enrolled in the college algebra offered as both oncampus instructor-based (traditional) and Web-based at the university of North Texas (UNT). A total of 36 Web-based students and 58 instructor-based students participated in this study. This study utilized a posttest-only intact group. The Kolb Learning Style Inventory (LSI) measured the learning styles of students. This study used learning methods (Web-based learning (WBL), instructor-based learning (IBL)), and learning styles (Diverger, Converger, Assimilator, and Accommodator) as independent variables. Student knowledge and student satisfaction was measured at the end of the course as independent variables. Based upon the results of the LSI, post-learning exam, and satisfaction a series of two-way analysis of variance (ANOVA 4x2) techniques and independent variable tests was used for each of the dependent variables, knowledge and satisfaction, based on a student's learning styles. The results revealed that students' learning styles were statistically …
Date: December 2001
Creator: Manochehri, Naser
System: The UNT Digital Library

Electroencephalographic (EEG) biofeedback treatment for children with attention deficit disorders in a school setting.

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The purpose of this study was to explore the use of EEG biofeedback in a school setting to assist students who had attentional challenges. The equipment for implementing biofeedback was relatively inexpensive and was easily integrated into the school setting. Twenty students ranging in age from 7 to 17 were recruited for this study. Data was used from 14 subjects, 12 males (2 Hispanic, 1 African American, and 10 Caucasian) and 2 females (1 Hispanic, 1 Caucasian.) The subject pool was reduced due to non-compliance or the students. moving from the school district. Significant effect size was obtained in the treatment group in areas pertaining to visual perception and motor coordination. However, significant effect sizes in other areas were obtained when the control group scores worsened. The inclusion of student subjects who, perhaps, did not meet stringent criterion of attention deficit may have skewed the results. The small number of students in the study may have hindered accurate measures of statistical significance. Conversely, the information obtained from this study may offer insight to school districts in providing their students an alternate/adjunct to psychopharmacological medication and a non- invasive method of helping students with psycho-social challenges.
Date: December 2001
Creator: Mosse, Leah Kathryn
System: The UNT Digital Library
An entropic approach to the analysis of time series. (open access)

An entropic approach to the analysis of time series.

Statistical analysis of time series. With compelling arguments we show that the Diffusion Entropy Analysis (DEA) is the only method of the literature of the Science of Complexity that correctly determines the scaling hidden within a time series reflecting a Complex Process. The time series is thought of as a source of fluctuations, and the DEA is based on the Shannon entropy of the diffusion process generated by these fluctuations. All traditional methods of scaling analysis, instead, are based on the variance of this diffusion process. The variance methods detect the real scaling only if the Gaussian assumption holds true. We call H the scaling exponent detected by the variance methods and d the real scaling exponent. If the time series is characterized by Fractional Brownian Motion, we have H¹d and the scaling can be safely determined, in this case, by using the variance methods. If, on the contrary, the time series is characterized, for example, by Lévy statistics, H ¹ d and the variance methods cannot be used to detect the true scaling. Lévy walk yields the relation d=1/(3-2H). In the case of Lévy flights, the variance diverges and the exponent H cannot be determined, whereas the scaling d …
Date: December 2001
Creator: Scafetta, Nicola
System: The UNT Digital Library
Fifth Grade Students as Emotional Helpers with Kindergarten Children, Using Play Therapy Procedures and Skills (open access)

Fifth Grade Students as Emotional Helpers with Kindergarten Children, Using Play Therapy Procedures and Skills

This research study investigated the effectiveness of a filial therapy training model as a method to train fifth grade students in child-centered play therapy skills and procedures. Filial therapy is an intervention that focuses on strengthening and enhancing adult-child relationships. The fifth grade students were trained to be a therapeutic change agent for kindergarten children identified as having adjustment difficulties, by utilizing basic child-centered play therapy skills in weekly play sessions with the kindergarten children. Specifically, this research determined the effectiveness of filial therapy in increasing the fifth grade students': 1) empathic responses with kindergarten children; 2) communication of acceptance with kindergarten children; 3) allowance of self-direction with kindergarten children, and 4) involvement in play activities of kindergarten children. The experimental group of fifth grade students (N=12) received thirty-five minutes of training twice a week for 5 weeks and then once a week for the duration of the 10 weeks of play sessions. The control group (N=11) received no training during the 15 weeks of the project. Fifth grade student participants were videotaped playing with a kindergarten child identified as having adjustment difficulties in 20-minute play sessions before and after the training to measure empathic behavior in adult-child interactions. Analysis …
Date: December 2001
Creator: Robinson, Julianna M. Ziegler
System: The UNT Digital Library
Form and Lyricism as Elements of Neo-Romanticism in Summer Music Op. 31 by Samuel Barber (1957) with three recitals of selected works by Bach, Mozart, Hindemith, Handel, Gaubert, and others (open access)

Form and Lyricism as Elements of Neo-Romanticism in Summer Music Op. 31 by Samuel Barber (1957) with three recitals of selected works by Bach, Mozart, Hindemith, Handel, Gaubert, and others

The music of Samuel Barber is well known in the vocal, piano, and string literature; however, little of his chamber music involves woodwinds, and in particular, only one work involves the woodwind quintet. Summer Music, originally commissioned as a septet, developed after the premiere of the work into the woodwind quintet version, with the assistance of the New York Woodwind Quintet. Barber is considered a contemporary .romantic. composer, evidenced through his use of lyricism. Summer Music, a standard in the woodwind quintet literature, should be included in every professional flutist's repertoire. The intent of this dissertation is to consider Barber's use of lyricism as a determinant of the form of Summer Music, as well as to compare the differences between the manuscript and the published edition.
Date: December 2001
Creator: Grosklos, Hollie Jo
System: The UNT Digital Library
The Impact of Poverty on Comparable Improvement Ranking for Elementary Campuses in Texas (open access)

The Impact of Poverty on Comparable Improvement Ranking for Elementary Campuses in Texas

The problem was to determine how comparable is comparable improvement for campuses in Texas. An alternative strategy for determining comparable improvement was developed using 2000 comparable improvement data provided by the Texas Education Agency for 2,403 elementary campuses. Comparable improvement is a measure that shows how student performance has changed from one year to the next and then compares that growth to 40 schools that are demographically most similar to the target school. Instead of using the most dominant characteristic as in the current process, the percent of students in poverty was the initial sorting characteristic. The impact of sorting by poverty was reviewed in four areas: 1.) the impact on quartile placement, 2.) the TLI average growth for the comparison group, 3.) the award eligibility, and 4.) the changes in comparison group composition. No practical significant difference was found for research questions 1 and 3, however, a practical significant difference was found in group average TLI growth for math and in the comparison group composition. Overall, the alternative process had the greatest impact on campuses with 40-80% poverty. Three possible factors may have influenced the results. First, the middle poverty campuses had the most change in comparison group as …
Date: December 2001
Creator: Holland, Vicki Gay
System: The UNT Digital Library
An investigation of the effects of SFAS No.121 on asset impairment reporting and stock returns (open access)

An investigation of the effects of SFAS No.121 on asset impairment reporting and stock returns

Prior to Statement of Financial Accounting Standards No.121 (SFAS No.121): Accounting for the Impairment of Long-Lived Assets and Long-Lived Assets to Be Disposed Of, managers had substantial discretion concerning the amount and timing of reporting writedowns of long-lived assets. Moreover, the frequency and dollar amount of asset writedown announcements that led to a large “surprise” caused the Financial Accounting Standards Board (FASB) and the Securities and Exchange Commission (SEC) to consider the need for a new standard to guide the recording of impairment of long-lived assets. This study has two primary objectives. First, it investigates the effects of SFAS No.121 on asset impairment reporting, examining whether SFAS No.121 reduces the magnitude and restricts the timing of reporting asset writedowns. Second, the study compares the information content (surprise element) of the asset impairment loss announcement as measured by cumulative abnormal returns (CAR) before and after the issuance of SFAS No.121. The findings provide support for the hypothesis that the FASB's new accounting standard does not affect the magnitude of asset writedown losses. The findings also provide support for the hypothesis that SFAS No. 121 does not affect the management choice of the timing for reporting asset writedowns. In addition, the findings …
Date: December 2001
Creator: Alshabani, Waleed Mohammad
System: The UNT Digital Library
Investigations of neuronal network responses to electrical stimulation in murine spinal cultures. (open access)

Investigations of neuronal network responses to electrical stimulation in murine spinal cultures.

Spontaneous activity in neuronal networks in vitro is common and has been well documented. However, alteration of spontaneous activity in such networks via conditioning electrical stimulation has received much less experimental attention. Two different patterns of electrical stimulation were used to enhance or depress the level of spontaneous activity in spinal cord cultures. High-frequency stimulation (HFS), a method routinely shown to increase the efficacy of synaptic transmission, was employed to augment spontaneous activity. Low-frequency stimulation (LFS), the technique often applied to depress synaptic efficacy, was employed to decrease spontaneous activity. In addition, LFS was used to reverse the effect of HFS on spontaneous activity. Likewise, HFS was applied to counter the effect of LFS. Because these networks were grown on multi-microelectrode plates (MMEPs), this allowed the simultaneous stimulation of any combination of the 64 electrodes in the array. Thus, the possible differences in response to single versus multi-electrode stimulation were also addressed. Finally, test-pulses were delivered before and after the conditioning stimulation on the same stimulation electrode(s) in order to assess the change in mean evoked action potentials (MEAPs). Dissociated spinal tissue from embryonic mice was allowed to mature into self-organized networks that exhibited spontaneous bursting activity after two weeks …
Date: December 2001
Creator: Sparks, Christopher A.
System: The UNT Digital Library
IS-MBNQA: A new framework for the relationship between Information Systems and organizational quality. (open access)

IS-MBNQA: A new framework for the relationship between Information Systems and organizational quality.

Despite numerous frameworks and models proposed in the literature, Information Systems (IS) assessment still remains elusive. In addition, little agreement exists on the contribution of the IS function within an organization and on how IS is related to the other organizational dimensions. Frameworks that show the relationship between IS and the organization are in the developmental stage and this work proposes a more comprehensive framework to assist in better understanding the relationship between IS and organizational quality. This research examines two popular IS quality assessment frameworks - Malcolm Baldrige National Quality Award (MBNQA) and Information Systems Assessment (ISA) - and suggests a new framework, IS-MBNQA. This work integrates these two IS quality assessment frameworks into a single comprehensive model that provides a holistic view on how IS quality is interrelated to organizational quality. The existing two IS assessment frameworks attempted to measure IS quality at different levels within an organization. The MBNQA model is the most comprehensive quality framework because it takes an organization wide perspective. On the other hand, ISA employs an IS specific perspective and reflects the relationships of eight major IS success dimensions. ISA is a modified version of DeLone & McLean's model with the inclusion of …
Date: December 2001
Creator: Chong, Hyonsong
System: The UNT Digital Library

Mechanisms of Methoxide Ion Substitution and Acid- Catalyzed Z/E Isomerization of N-Methoxyimines

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The second order rate constants for nucleophilic substitution by methoxide of (Z)- and (E)-O-methylbenzohydroximoyl fluorides [C6H4C(F)=NOCH3] with various substituents on the phenyl ring [p-OCH3 (1h, 2h), p-CH3 (1g, 2g), p-Cl (1f, 2f), p-H (1e, 2e), (3,5)-bis-CF3 (1i, 2i)] in 90:10 DMSO:MeOH have been measured. A Hammett plot of these rate constants vs σ values gave positive ρ values of 2.95 (Z isomer) and 3.29 (E isomer). Comparison of these rates with methoxide substitution rates for Omethylbenzohydroximoyl bromide [C6H4C(Br)=NOCH3] and Omethylbenzohydroximoyl chloride [C6H4C(Cl)=NOCH3] reveal an element effect for the Z isomers of Br:Cl:F(1e) = 2.21:1.00:79.7 and for the E isomers of Cl:F(2e) = 1.00:18.3. With the p-OCH3-imidoyl halides the following element effects are found: Br:Cl:F(1h) = 2.78:1.00:73.1 for the Z isomer and Br:Cl:F(2h) = 1.97:1.00:12.1 for the E isomer. Measurement of activation parameters revealed ∆S≠ = -17 eu for 1e and ∆S≠ = -9.9 eu for 2e. Ab initio calculations (HF/6-31+G*, MP2/6-31+G*//HF/6-31+G*, B3LYP/6- 31+G*//HF/6-31+G*, HF-SCIPCM/6-31+G*//HF/6-31+G*) were performed to define the reaction surface. These calculations demonstrate a relatively large barrier for nucleophilic attack in relation to halogen loss and support the experimental findings that this reaction proceeds by an addition-elimination mechanism (AN# + DN). The imidoyl fluorides have been used to synthesize …
Date: December 2001
Creator: Dolliver, Debra D.
System: The UNT Digital Library
The mediating and moderating effects of women's attachment style on interrelationships among emotional abuse, physical aggression and relational stability. (open access)

The mediating and moderating effects of women's attachment style on interrelationships among emotional abuse, physical aggression and relational stability.

This purpose of this study was to combine two bodies of literature on relationships, attachment and violence. Given the impact of men's physical aggression and emotional abuse on women, it is likely that these behaviors would also affect attachment. A model proposing that women's attachment style mediated and moderated the relationship between partners' physical and emotional abuse and the stability of women's relationships was tested. Archival data were used from two waves of interviews with a sample of lowincome, ethnically diverse community women. Most (89%) of the initial 835 participants of Project HOW: Health Outcomes of Women completed at least one additional interview providing information on the status of their initial relationships. Of these women, 39% were African American, 30% were Euro-American, and 31% were Mexican American. The effects of men's psychological abuse and physical violence on women's attachment style were tested with regression analyses. The interrelationships between partners' abuse, attachment and relational stability were tested with SEM. Attachment style was expected to moderate the associations among variables and mediate the impact of partners' negative behavior on relational stability. In regression analyses, partners' psychological abuse predicted avoidant and anxious, but not secure attachment ratings. Violence, although significant, explained less variance …
Date: December 2001
Creator: Weston, Rebecca
System: The UNT Digital Library

A meta-analysis of service learning research in middle and high schools.

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This study examines the relationship between service learning innovations and improved academics, self-concept, and social or personal growth in middle and high school students. Meta-Analysis is employed to arrive at effect-size estimates for each construct. A historical overview of service learning is presented and a detailed description of the study selection process is provided. The data revealed a moderate relationship between service learning participation and academics, self-concept and social or personal growth in middle and high school students. The findings are presented, and some appropriate conclusions are drawn. A discussion of the implications of these findings and recommendations for future research are also provided.
Date: December 2001
Creator: White, Amy E.
System: The UNT Digital Library
Metal-Aluminum Oxide Interactions: Effects of Surface Hydroxylation and High Electric Field (open access)

Metal-Aluminum Oxide Interactions: Effects of Surface Hydroxylation and High Electric Field

Metal and oxide interactions are of broad scientific and technological interest in areas such as heterogeneous catalysis, microelectronics, composite materials, and corrosion. In the real world, such interactions are often complicated by the presence of interfacial impurities and/or high electric fields that may change the thermodynamic and kinetic behaviors of the metal/oxide interfaces. This research includes: (1) the surface hydroxylation effects on the aluminum oxide interactions with copper adlayers, and (2) effects of high electric fields on the interface of thin aluminum oxide films and Ni3Al substrate. X-ray photoelectron spectroscopy (XPS) studies and first principles calculations have been carried out to compare copper adsorption on heavily hydroxylated a- Al2O3(0001) with dehydroxylated surfaces produced by Argon ion sputtering followed by annealing in oxygen. For a heavily hydroxylated surface with OH coverage of 0.47 monolayer (ML), sputter deposition of copper at 300 K results in a maximum Cu(I) coverage of ~0.35 ML, in agreement with theoretical predictions. Maximum Cu(I) coverage at 300 K decreases with decreasing surface hydroxylation. Exposure of a partially dehydroxylated a-Al2O3(0001) surface to either air or 2 Torr water vapor results in recovery of surface hydroxylation, which in turn increases the maximum Cu(I) coverage. The ability of surface hydroxyl …
Date: December 2001
Creator: Niu, Chengyu
System: The UNT Digital Library