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Attitudes toward Research and Teaching: Differences Between Faculty and Administrators at Three Saudi Arabian Universities
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This study is an investigation of the perceived attitudinal differences between administrators and faculty toward research and teaching at three Saudi Arabian universities, King Saud University (KSU), King Fahd University of Petroleum and Minerals (KFUPM), and the Islamic University (IU). The researcher also investigated the effect of several variables, such as rank, university, and academic field on administrators and faculty members' attitudes toward teaching and research. Little Attention has been given to studies that examine the differences between faculty and administrators with regard to their attitudes toward the priorities of teaching and research in Saudi Arabian institutions. Also, little research has been conducted regarding the effects of rank and academic field on faculty attitudes in Saudi Arabian institutions. The author used a mail survey and collected 518 useable responses from a total of 710 questionnaires distributed. Factor analysis, MANCOVA, MANOVA, and ANOVA were the statistical methods employed in data analysis. Five attitudes were identified as a result of factor analysis: (a) attitudes toward teaching; (b) attitudes toward research; (c) mission; (d) promotion; and (e) interest. Results indicated that there was a significant difference between faculty and administrators regarding teaching and resea4rch. Administrators showed stronger attitudes toward teaching than faculty at …
Date:
May 2000
Creator:
Alsouhibani, Mohammed A.
System:
The UNT Digital Library
Evidentiary Value of Condoms: Comparison of Durable Physical and Chemical Characteristics of Condoms
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Condom trace evidence must not be overlooked in sexual assault cases; understanding the chemical and physical characteristics of condoms is imperative if condoms are to be useful evidence. Previous research shows that condom identification is possible, but it is equally important to evaluate durability of condom residues versus time. Using FT-IR, this study examined vaginal swabs from subjects who self-sampled at intervals for up to 72 hours after having intercourse with a condom. This study investigated whether age and the stage of the menstrual cycle affected the durability of residues in the vagina over time. This study revealed that condoms containing nonoxynol-9, silicone-based lubricants, and particulates provide valuable information for identification, and that nonoxynol-9 specifically withstands the vaginal environment for up to 72 hours. Additionally, age and menstrual cycle both appeared to have an effect on the durability of residues although larger sample size is desirable.
Date:
May 2000
Creator:
Belcher, Kelly Leigh
System:
The UNT Digital Library
Gunther Schuller and John Swallow: Collaboration, Composition, and Performance Practice in Eine Kleine Posaunenmusik, with Three Recitals of Selected Works by Berio, Bogle, Gregson, Pryor, Suderburg and Others
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Gunther Schuller is credited with coining the term Third Stream, meaning compositions where twentieth-century art music forms exist simultaneously with jazz. Furthermore, Schuller specifically states in the liner notes to the debut recording of Eine Kleine Posaunenmusik "The work is not a Third Stream piece." Yet the concerto alludes to jazz through a multitude of slide glissandi and plunger mute effects, Solotone mute passages, specific references to the jazz trombone styles of Tommy Dorsey and Lawrence Brown, musical quoting or indirect reference, and the use of a walking bass line in Movement V, Finale. What makes one piece Third Stream and another simply a modern composition with jazz implications? Is Third Stream primarily a compositional designation or a performance practice stipulation? How does a celebrated trombone soloist inspire and collaborate with a distinguished composer in the creation of a major work? The somewhat conspicuous title, Eine Kleine Posaunenmusik, seems to point towards Mozart's famous string serenade Eine Kleine Nachtmusik. What connection to Mozart, if any, does Schuller's title suggest? All of these questions are elucidated in this study through careful investigation and research of Gunther Schuller's Eine Kleine Posaunenmusik. New interviews with John Swallow and Gunther Schuller are included.
Date:
May 2000
Creator:
Bogle, James Michael
System:
The UNT Digital Library
Microstructure and Electronic Structures of Er-Doped Si Nano-particles Synthesized by Vapor Phase Pyrolysis
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Si nanoparticles are new prospective optoelectronic materials. Unlike bulk Si cry-stals, Si nanoparticles display intriguing room-temperature photoluminescence. A major challenge in the fabrication of Si nanoparticles is the control of their size distribution. The rare-earth element Er has unique photo emission properties, including low pumping power, and a temperature independent, sharp spectrum. The emission wavelength matches the transmission window of optical fibers used in the telecommunications industry. Therefore, the study of Er-doped Si nanoparticles may have practical significance. The goals of the research described in this dissertation are to investigate vapor phase pyrolysis methods and to characterize the microstructure and associated defects, particles size distributions and photoluminescence efficiencies of doped and undoped Si nanoparticles using analytical transmission electron microscopy, high resolution electron microscopy, and optical spectroscopy. Er-doped and undoped Si nanoparticles were synthesized via vapor-phase pyrolysis of disilane at Texas Christian University. To achieve monodisperse size distributions, a process with fast nucleation and slow growth was employed. Disilane was diluted to 0.48% with helium. A horizontal pyrolysis oven was maintained at a temperature of 1000 °C. The oven length was varied from 1.5 cm to 6.0 cm to investigate the influence of oven length on the properties of the nanoparticles. …
Date:
May 2000
Creator:
Chen, Yandong
System:
The UNT Digital Library
Wayward Women, Virtuous Violence: Feminine Violence in Restoration and Eighteenth-Century British Literature by Women
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This dissertation examines the role of "acceptable" feminine violence in Restoration and eighteenth-century drama and fiction. Scenes such as Lady Davers's physical assault on Pamela in Samuel Richardson's Pamela (1740) have understandably troubled recent scholars of gender and literature. But critics, for the most part, have been more inclined to discuss women as victims of violence than as agents of violence. I argue that women in the Restoration and eighteenth century often used violence in order to maintain social boundaries, particularly sexual and economic ones, and that writers of the period drew upon this tradition of acceptable feminine violence in order to create the figure of the violent woman as a necessary agent of social control. One such figure is Violenta, the heroine of Delarivier Manley's novella The Wife's Resentment (1720), who murders and dismembers her bigamous husband. At her trial, Violenta is condemned to death "notwithstanding the Pity of the People" and "the Intercession of the Ladies," who believe that although the "unexampled Cruelty [Violenta] committed afterwards on the dead Body" was excessive, the murder itself is not inexcusable given her husband's bigamy. My research draws upon diverse archival materials, such as conduct manuals, criminal biographies, and legal records, …
Date:
May 2000
Creator:
Collins, Margo
System:
The UNT Digital Library
Playing Jonah's Hand: Poems
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Playing Jonah's Hand: Poems is a collection of poems with a critical introduction. The introduction consists of two independent essays, both of which examine intersections between poetry and Christian theology. In the first essay I identify the imaginative faculty as the primary source of agency for the speaker in John Donne's "Holy Sonnets." Working upon Barbara Lewalski's assertion that these sonnets represent "the Protestant paradigm of salvation in its stark, dramatic, Pauline terms," I consider the role of the imagination in the spiritual transformation represented within the sequence. Donne foregrounds a Calvinistic theology that posits both humanity's total depravity and God's grace and mercy as the only avenue of transcendence. Whatever agency the speaker exhibits is generated by the exercise of his imagination, which leads him to a recognition of his sinfulness and the necessity of God's grace. In the second essay I investigate the presence of a negative theology within "Lachrimae, or Seven Tears Figured in Seven Passionate Pavans," a sonnet sequence by Geoffrey Hill. In this sequence, Hill demonstrates the possibilities that surface through an integration of negative theology with postmodern theories of language, both of which have been influenced by the philosophical writings of Martin Heidegger. The …
Date:
May 2000
Creator:
Dyer, Gregory A.
System:
The UNT Digital Library
Parents' Beliefs and Knowledge Regarding Child Development and Appropriate Early Childhood Classroom Practices
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The intent of this study was to assess low-income parents knowledge and beliefs regarding child development and appropriate classroom practice and to compare their responses with those obtained from a previous survey of upper-income parents (Grebe, 1998). This study group (N=21) consisted of parents or guardians with children in a federally subsidized child-care center. Results indicated a high level of knowledge regarding developmentally appropriate practice and child development. Overall, there were no significant differences in the knowledge between the two income-levels, however, responses to several questions revealed slight differences in beliefs.
Date:
May 2000
Creator:
Hughes, Tina M.
System:
The UNT Digital Library
Depression, Anxiety, Self-Esteem, and Coping in Children and Adolescents Newly Diagnosed with Cancer and Children and Adolescents on Cancer Treatment for a Period of Seven Months or Longer
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Differences in self-reported depression, anxiety, self-esteem, and coping were evaluated in two groups of pediatric oncology patients: newly diagnosed (less than six months post-diagnosis) (n=5) and patients on cancer treatment for seven months or longer (n=5). Participants (6 males, 4 females, ages 7-17 years) completed the Children's Depression Inventory (CDI), the State-Trait Anxiety Inventory for Children (STAIC), and the Culture-Free Self-Esteem Inventory (CFSEI-2); nine of the ten participants discussed in a semi-structured interview their personal experiences and feelings about having cancer. Although the newly diagnosed group had a higher mean score on the CDI than the 7 months or greater group, the difference was not significant (p = .054). The newly diagnosed group also had higher mean state and trait anxiety scores on the STAIC, indicating higher anxiety levels, and a slightly lower CFSEI-2 mean score, indicating slightly lower self-esteem than the 7 months or greater group, but differences were not at a statistically significant level (p>.05).
Date:
May 2000
Creator:
Jones, Tracy L.
System:
The UNT Digital Library
An Analysis of the Composition Process of Bartók's Eight Improvisations on Hungarian Peasant Songs, Op. 20
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This is a study of Bartók's compositional process as it relates to the Improvisations, Op. 20. The study, which focuses on the analysis of the draft manuscript 50PS1, compares the draft and other relevant sources with the final composition. Bartók's framework for the entire Improvisations is based on a compositional strategy of pairing individual improvisations combined with systematic revision of the draft copy by the introduction of tritones as tonal equivalents and movement by fifths from semitones, to achieve structural coherence in the individual improvisations. The tonic-dominant relationship is used to rearrange the individual improvisations in the draft and tritones as tonal equivalents are used to propel the movement between the improvisations to produce a coherent whole.
Date:
May 2000
Creator:
Kochbeck, Olivia M.
System:
The UNT Digital Library
Empirical Evidence of Pricing Efficiency in Niche Markets
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Unique and proprietary data of the illiquid, one-year non cancelable for three month Bermudan swaps (1Y NC 3M swaps) and one-year non callable for three months Bermudan CDs (1Y NC 3M CDs), provides evidence of market efficiency. The 1Y NC 3M swap and 1Y NC 3M CD markets efficiently reflected unexpected economic information. The 1Y NC 3M swaption premiums also followed the European one-year into three-month (1Y into 3M) swaption volatilities. Swaption premiums were computed by pricing non-optional instruments using the quoted 1Y NC 3M swap rates and the par value swap rates and taking the difference between them. Swaption premiums ranged from a slight negative premium to a 0.21 percent premium. The average swaption premium during the study period was 0.02 percent to 0.04 percent. The initial swaption premiums were over 0.20 percent while the final swaption premiums were 0.02 percent to 0.04 percent. Premiums peaked and waned throughout the study period depending on market uncertainty as reflected in major national economic announcements, Federal Reserve testimonies and foreign currency devaluations. Negative swaption premiums were not necessarily irrational or quoting errors. Frequently, traders obligated to provide market quotes to customers do not have an interest and relay that lack of …
Date:
May 2000
Creator:
Koch, Sandra Idelle
System:
The UNT Digital Library
Young-Jo Lee's Variations on the theme of Baugogae: In search of his own language, a lecture recital, together with three recitals of selected works of J. Haydn, S. Rachmaninoff, R. Schumann, O. Messiaen, and F. Liszt
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The objective of the dissertation is to examine Young-Jo Lee's (b. 1943) musical language as exhibited in his piano composition, Variations on the theme of Baugogae. Subjects of discussion include Lee's use of direct and indirect musical borrowings from past European composers and traditional Korean folk idioms. Also included are a biographical sketch of the composer and historical overview of modern Korean composers. This dissertation investigates Lee's effort to synthesize traditional Korean music and Western music in one art form and ultimately, to create his own musical language.
Date:
May 2000
Creator:
Kwon, Suk-Rahn
System:
The UNT Digital Library
Utilization of the family medical leave act: A case study
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American businesses have confronted a changing world economy marked by increasing competition , technological innovation, and instability. Many more women have entered the labor force. Many families' caregiving needs are now being met by family members who also are holding down jobs. This, in turn, has fueled the rising need among employees for workplace policies that enable them to meet the often competing demands of job and home. In 1993, Congress passed the Family and Medical Leave Act (FMLA of the Act) to provide a national policy that supports families in their efforts to strike a workable balance between the competing demands of the workplace and the home. The objective of this study is to examine the amount of FMLA lost time at one particular company in order to determine a demographic and job characteristic profile of employees who take time away from their jobs for reasons that are protected by the Act.
Date:
May 2000
Creator:
Mahdi, Taalib-Din N.
System:
The UNT Digital Library
The Reformation-Era Church Courts of England: A Study of the Acta of the Archidiaconal and Consistory Court at Chester, 1540-1542
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Much work has been done over the last fifty years in the study of the English ecclesiastical courts. One court that thus far has escaped much significant scholarly attention, however, is the one located in Chester, England. The author analyzes the acta of that court in order to determine what types of cases were being heard during the years 1540-42. His analysis shows that the Chester court did not deviate significantly from the general legal and theological structure and function of Tudor church courts of the period.
Date:
May 2000
Creator:
Mitchener, Donald Keith
System:
The UNT Digital Library
A Study of Graphically Chosen Features for Representation of TREC Topic-Document Sets
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Document representation is important for computer-based text processing. Good document representations must include at least the most salient concepts of the document. Documents exist in a multidimensional space that difficult the identification of what concepts to include. A current problem is to measure the effectiveness of the different strategies that have been proposed to accomplish this task. As a contribution towards this goal, this dissertation studied the visual inter-document relationship in a dimensionally reduced space. The same treatment was done on full text and on three document representations. Two of the representations were based on the assumption that the salient features in a document set follow the chi-distribution in the whole document set. The third document representation identified features through a novel method. A Coefficient of Variability was calculated by normalizing the Cartesian distance of the discriminating value in the relevant and the non-relevant document subsets. Also, the local dictionary method was used. Cosine similarity values measured the inter-document distance in the information space and formed a matrix to serve as input to the Multi-Dimensional Scale (MDS) procedure. A Precision-Recall procedure was averaged across all treatments to statistically compare them. Treatments were not found to be statistically the same and …
Date:
May 2000
Creator:
Oyarce, Guillermo Alfredo
System:
The UNT Digital Library
Sorry Guard
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Sorry Guard is a collection of poems with a critical introduction on poetic form. Form in poetry can be revealed vocally (how the poem sounds), temporally (how the poem makes use of time), and spatially (how the poem is visualized, both physically on the page due to typography and imagistically due to the shape and movement of its subject matter). In this preface, I will address these three aspects of form in relation to three distinct twentieth century poets: Robert Hass, W.S. Merwin, and W.H. Auden. I am most interested in how particular formal decisions shape meaning and value in poetry. My aesthetic approach here primarily dwells on what Helen Vendler calls, "the music of what happens." The urgency of Robert Hass's spoken word is important to me because I wish to make poems that should be spoken aloud and remembered. While W.S. Merwin's rejection of punctuation is not my own aesthetic outlook, I strive to achieve through close attention to temporal form the mythic voice of his poemsthe immediacy of his lines and images, especially in his second four books. And Auden's deft use of spatial form is only a small aspect of his remarkable verse. All three poets …
Date:
May 2000
Creator:
Poch, John
System:
The UNT Digital Library
Exogenous Influences and Paths To Activism
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The focus of this research was to ascertain the indirect effects upon activism of intervening variables and recognized exogenous influences upon activism. In addition, this research also focused upon the differences and similarities of a recruited activist model and spontaneous activist model. Regression and path analysis were used to measure the direct and indirect effects of the exogenous and intervening variables. This research found that when the intervening variables, political interest, political awareness, exposure to media, altruism, and self-interest were introduced to both the recruited and spontaneous models, the direct effects of the variables were enhanced.
Date:
May 2000
Creator:
Ray, Grady Dale
System:
The UNT Digital Library
An Online Academic Support Model for Students Enrolled in Internet-Based Classes
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This doctoral dissertation describes a research study that examined the effectiveness of an experimental Supplemental Instruction (SI) program that utilized computer-mediated communication (CMC) rather than traditional SI review sessions. During the Spring 1999 semester, six sections of an introductory computer course were offered via the Internet by a suburban community college district in Texas. Using Campbell and Stanley's Nonequivalent Control Group model, the online SI program was randomly assigned to four of the course sections with the two remaining sections serving as the control group. The students hired to lead the online review sessions participated in the traditional SI training programs at their colleges, and received training conducted by the researcher related to their roles as online discussion moderators. Following recommendations from Congos and Schoeps, the internal validity of the groups was confirmed by conducting independent t-tests comparing the students' cumulative credit hours, grade point averages, college entrance test scores, and first exam scores. The study's four null hypotheses were tested using multiple linear regression equations with alpha levels set at .01. Results indicated that the SI participants earned better course grades even though they had acquired fewer academic credits and had, on average, scored lower on their first course …
Date:
May 2000
Creator:
Rockefeller, Debra J.
System:
The UNT Digital Library
Work-family responsiveness in organizations: The influence of resource dependence and institutionalization on program adaptation
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Changes in workforce demographics, employee sentiments, and working conditions have increased attention on employees' needs to balance the demands of work life and family life. Despite apparent growing interest among companies to be responsive to these needs, the number of companies demonstrating high levels of work-family responsiveness is relatively small. The frameworks of resource dependence theory and institutional theory were used to develop a model to explain differences in work-family responsiveness among for-profit companies. The theoretical models were tested on survey data collected through a stratified random sample of 692 for-profit companies. The data were further enhanced with secondary data sources. While the institutional model explained more variance in work-family responsiveness than the resource dependence model, a model combining both theories best explains work-family responsiveness among for-profit companies. High industry-region diffusion of family-friendly benefits was one of several strong predictors of work-family responsiveness. Also, the greater the proportion of professionals in a company's industry, the greater was the level of work-family responsiveness. Companies that measured effectiveness outcomes were more likely to offer family-friendly benefits. The same was true for companies with more positive assessments regarding the impact of their family-friendly benefits. Organizations that were large, publicly traded, or had human …
Date:
May 2000
Creator:
Ruggiere, Paul
System:
The UNT Digital Library
Virginia Carter Smith: Her Career and Contributions to Advancement in Higher Education
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Most research studies of women in the college and university advancement profession measure the number of women in advancement positions, report their corresponding salaries and reflect on the differences between male and female employees in the same position. Little research explores how women achieve high ranking advancement positions and very few provide an analysis of the characteristics, influences and careers of successful female advancement professionals. This dissertation describes the life and work of Virginia Carter Smith, founding editor of the Council for Advancement and Support of Education's award winning publication CURRENTS. The career and contributions of Virginia Carter Smith are relevant and helpful to advancement professionals in colleges, universities and K-12 institutions. This study explores Smith's formative years as a child, describes her educational and extra-curricular preparation and identifies individuals who influenced her life and provided direction for her future. It also examines Smith's role in the formation and direction of CASE and CURRENTS. Smith successfully launched CURRENTS in 1975 when few women held senior-level positions in advancement-related fields. With Smith's contributions, CASE became the dominate professional organization for advancement professionals working in educational institutions, and CURRENTS continues to be an exemplary professional development periodical for individuals working in advancement. …
Date:
May 2000
Creator:
Russell, Kimberly A.
System:
The UNT Digital Library
Macroinvertebrate Community Structure as an Indicator of Watershed Health in the Upper Trinity River Basin, North Central Texas
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This study describes macroinvertebrate community structure and assesses its potential in detecting point and non-point sources of disturbance associated with rural and urban areas in the Upper Trinity River Basin. Geospatial techniques were used to quantify landuse within the watershed in a GIS. At rural sites near the headwaters of the Trinity River, collector-gathering burrowers that are adapted to minimal flow comprised the majority of taxa. Destinies of taxa compositions at downstream sites increased and shifted toward psammophilic and rheophilic invertebrates, including primarily collector-filtering clingers, that are characteristic of shifting sand habitats in large prairie rivers. Benthic community structure generally benefited from point source impacts including wastewater treatment plant effluents that maintained higher flow. Community indices were negatively associated with forest landuse and positively associated with urban landuse. Partial CCA determined that flow and landuse contributed equally to species dispersions. Comparisons with historical biomonitoring studies in upper Trinity River Basin indicate improved watershed health.
Date:
May 2000
Creator:
Stephenson, Jaynie M.
System:
The UNT Digital Library
Scanning Tunneling Microscopy of Homo-Epitaxial Chemical Vapor Deposited Diamond (100) Films
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Atomic resolution images of hot-tungsten filament chemical-vapor-deposition (CVD) grown epitaxial diamond (100) films obtained in ultrahigh vacuum (UHV) with a scanning tunneling microscope (STM) are reported. A (2x1) dimer surface reconstruction and amorphous atomic regions were observed on the hydrogen terminated (100) surface. The (2x1) unit cell was measured to be 0.51"0.01 x 0.25"0.01 nm2. The amorphous regions were identified as amorphous carbon. After CVD growth, the surface of the epitaxial films was amorphous at the atomic scale. After 2 minutes of exposure to atomic hydrogen at 30 Torr and the sample temperature at 500° C, the surface was observed to consist of amorphous regions and (2x1) dimer reconstructed regions. After 5 minutes of exposure to atomic hydrogen, the surface was observed to consist mostly of (2x1) dimer reconstructed regions. These observations support a recent model for CVD diamond growth that is based on an amorphous carbon layer that is etched or converted to diamond by atomic hydrogen. With further exposure to atomic hydrogen at 500° C, etch pits were observed in the shape of inverted pyramids with {111} oriented sides. The temperature dependence of atomic hydrogen etching of the diamond (100) surface was also investigated using UHV STM, and …
Date:
May 2000
Creator:
Stallcup, Richard E.
System:
The UNT Digital Library
The Cluster Hypothesis: A Visual/Statistical Analysis
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By allowing judgments based on a small number of exemplar documents to be applied to a larger number of unexamined documents, clustered presentation of search results represents an intuitively attractive possibility for reducing the cognitive resource demands on human users of information retrieval systems. However, clustered presentation of search results is sensible only to the extent that naturally occurring similarity relationships among documents correspond to topically coherent clusters. The Cluster Hypothesis posits just such a systematic relationship between document similarity and topical relevance. To date, experimental validation of the Cluster Hypothesis has proved problematic, with collection-specific results both supporting and failing to support this fundamental theoretical postulate. The present study consists of two computational information visualization experiments, representing a two-tiered test of the Cluster Hypothesis under adverse conditions. Both experiments rely on multidimensionally scaled representations of interdocument similarity matrices. Experiment 1 is a term-reduction condition, in which descriptive titles are extracted from Associated Press news stories drawn from the TREC information retrieval test collection. The clustering behavior of these titles is compared to the behavior of the corresponding full text via statistical analysis of the visual characteristics of a two-dimensional similarity map. Experiment 2 is a dimensionality reduction condition, in …
Date:
May 2000
Creator:
Sullivan, Terry
System:
The UNT Digital Library
The Validity of Health Claims on the World Wide Web: A Case Study of the Herbal Remedy Opuntia
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The World Wide Web has become a significant source of medical information for the public, but there is concern that much of the information is inaccurate, misleading, and unsupported by scientific evidence. This study analyzes the validity of health claims on the World Wide Web for the herbal Opuntia using an evidence-based approach, and supports the observation that individuals must critically assess health information in this relatively new medium of communication. A systematic search by means of nine search engines and online resources of Web sites relating to herbal remedies was conducted and specific sites providing information on the cactus herbal remedy from the genus Opuntia were retrieved. Validity of therapeutic health claims on the Web sites was checked by comparison with reports in the scientific literature subjected to two established quality assessment rating instruments. 184 Web sites from a variety of sources were retrieved and evaluated, and 98 distinct health claims were identified. 53 scientific reports were retrieved to validate claims. 25 involved human subjects, and 28 involved animal or laboratory models. Only 33 (34%) of the claims were addressed in the scientific literature. For 3% of the claims, evidence from the scientific reports was conflicting or contradictory. Of …
Date:
May 2000
Creator:
Veronin, Michael A.
System:
The UNT Digital Library
Conformational Studies of Myosin and Actin with Calibrated Resonance Energy Transfer
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Resonance energy transfer was employed to study the conformational changes of actomyosin during ATP hydrolysis. To calibrate the technique, the parameters for resonance energy transfer were defined. With conformational searching algorithms to predict probe orientation, the distances measured by resonance energy transfer are highly consistent with the atomic models, which verified the accuracy and feasibility of resonance energy transfer for structural studies of proteins and oligonucleotides. To study intramyosin distances, resonance energy transfer probes were attached to skeletal myosin's nucleotide site, subfragment-2, and regulatory light chain to examine nucleotide analog-induced structural transitions. The distances between the three positions were measured in the presence of different nucleotide analogs. No distance change was considered to be statistically significant. The measured distance between the regulatory light chain and nucleotide site was consistent with either the atomic model of skeletal myosin subfragment-1 or an average of the three models claimed for different ATP hydrolysis states, which suggested that the neck region was flexible in solution. To examine the participation of actin in the powerstroke process, resonance energy transfer between different sites on actin and myosin was measured in the presence of nucleotide analogs. The efficiencies of energy transfer between myosin catalytic domain and actin …
Date:
May 2000
Creator:
Xu, Jin
System:
The UNT Digital Library