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Mechanical Properties of Polymer Modified Mortar

Mechanical Properties of Polymer Modified Mortar

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Date: August 2002
Creator: Palos, Artemio
Description: The mechanical properties of the polymer-modified mortar are markedly improved over conventional cement mortar. We utilized recycled ABS in powder form and a polymer latex emulsion, polymer percentage ranges from 0 to 25 percent by polymer/cement ratio were investigated. The mechanical properties investigated were compression strength and adhesion strength. Compression strength effects did not have an impact on adhesion strength. Adhesion strength was calculated with pullout testing apparatus designed by the author. Results indicate that recycled ABS had a lower adhesive strength than the acrylic latex emulsion and the base mortar, but did increase in adhesive strength when mixed with maleic-anhydride. The adhesive strength was investigated for a Fiber Reinforced Polymer (FRP) made of an "E" glass fiber that is a continuous strand roving oriented and pre-tensioned longitudinally in an isopthalic polyester matrix material. The FRP rebar was compared to standard steel rebars, and found that the standard steel corrugated rebar had a higher adhesive strength, due to mechanical interlocking. This was clarified by measurements using a smooth steel rebar. Characterization of the polymer-modified mortar was conducted by pore analysis and scanning electron microscopy. Scanning Electron Microscopy was implemented to view the polymer particles, the cement fibrils formed by the ...
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Mechanisms of rapid receptive field reorganization in rat spinal cord

Mechanisms of rapid receptive field reorganization in rat spinal cord

Date: August 2002
Creator: Vu, Hung
Description: Rapid receptive field (RF) reorganization of somatosensory neurons in the rat dorsal horn was examined using extracellular single unit recording. Subcutaneous injection of lidocaine into RFs of dorsal horn neurons results in expansion of their RFs within minutes. The expanded RFs appear adjacent to or/and proximal to original RFs. Out of 63 neurons tested, 36 (58%) show RF reorganization. The data suggest that dorsal horn of spinal cord is one of the initial sites for RF reorganization. The neural mechanisms of this effect are not well understood. We propose that changes in biophysical properties (membrane conductance, length constant) of the neurons resulting from lidocaine injection contribute to RF reorganization. Iontophoretic application of glutamate onto dorsal horn neurons that show lidocaine induced RF's expansion were used to test the model. Application of glutamate produced reduction of reorganized RFs in 9 of 20 (45%) tested cells. Application of NBQX produced no effect on either original or expanded RFs indicate that RF shrinkage effects of glutamate involve NMDA receptors. The results are consistent with the prediction of the proposed model. Subcutaneous injection of capsaicin into tactile RFs of low threshold mechanoreceptive dorsal horn neurons produced no effect on the RF sizes that are ...
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Mental Health Professionals' Comparative Evaluations of the Integral Intake, The Life-Style Introductory Interview, and the Multimodal Life History Inventory

Mental Health Professionals' Comparative Evaluations of the Integral Intake, The Life-Style Introductory Interview, and the Multimodal Life History Inventory

Date: August 2002
Creator: Marquis, Andre
Description: This research study was performed in an attempt to fill an apparent void regarding the relative utility and comprehensiveness of three published, theoretically-based, idiographic, initial assessment inventories: Integral Intake (II), Life-Style Introductory Interview (LI), and Multimodal Life History Inventory (MI). “Experts” -- defined as professors of counseling or psychology and licensed practitioners who have been practicing as counselors or psychologists for at least five years - read through the inventories and then evaluated them by responding to both (qualitative) open-ended questions as well (quantitative) rankings and ratings. The researcher posed three primary research questions: 1) how do participants' evaluations differ regarding the overall helpfulness of the three inventories; 2) how do participants' evaluations differ regarding the comprehensiveness -- both relative to each of the eight dimensions of the client (thoughts, emotions, behaviors, physical aspects of the client, physical aspects of the client's environment, culture, spirituality, and what is most meaningful to the client) and overall -- of the three inventories; and 3) how do participants' evaluations differ regarding the efficiency with which the three inventories assessed the eight dimensions. Results indicated that participants consistently evaluated the II and MI as more helpful, comprehensive, and efficient than the LI - both ...
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A model for the development of disordered eating among lesbians

A model for the development of disordered eating among lesbians

Date: August 2002
Creator: Joshua, Michelle D.
Description: It has only been in recent years that eating disorder researchers have begun focusing on sexual orientation as a variable that may affect prevalence rates. Heeding the call for studies that extend beyond identification of fixed eating disorder risk factors (e.g., gender), this study was designed to explore factors that contribute to the development of disordered eating among lesbians. In this study, a hypothesized Lesbian Model of Disordered Eating was tested using structural equation modeling. Lesbian Sexual Identity and Social Supports were hypothesized to positively influence Psychological Health. In addition, Internalization of U.S. Societal Norms of beauty and attractiveness was hypothesized to negatively affect Psychological Health. Psychological Health, in turn, was hypothesized to negatively influence Body Image Concerns. Body Image Concerns was then hypothesized to positively affect Disordered Eating. The fit of the model was evaluated and one of the hypothesized pathways, Internalization of Norms was moved to directly predict Body Image Concerns. After adjusting the model, the model accounted for 54% of the variance in disordered eating. Most notably, the results highlight the potential affects of adopting a positive lesbian identity on disordered eating and underscore the importance of including sexual identity as a demographic variable in studies of ...
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Neuronal Network Analyses in vitro of Acute Individual and Combined Responses to Fluoxetine and Ethanol

Neuronal Network Analyses in vitro of Acute Individual and Combined Responses to Fluoxetine and Ethanol

Date: August 2002
Creator: Xia,Yun
Description: Embryonic murine neuronal networks cultured on microelectrode arrays were used to quantify acute electrophysiological effects of fluoxetine and ethanol. Spontaneously active frontal cortex cultures showed highly repeatable, dose-dependent sensitivities to both compounds. Cultures began to respond to fluoxetine at 3 µM and were shut off at 10-16 µM. EC50s mean ± S.D. for spike and burst rates were 4.1 ± 1.5 µM and 4.5 ± 1.1 µM (n=14). The fluoxetine inhibition was reversible and without effect on action potential wave shapes. Ethanol showed initial inhibition at 20 mM, with spike and burst rate EC50s at 52.0 ± 17.4 mM and 56.0 ± 17.0 mM (n=15). Ethanol concentrations above 100 -140 mM led to cessation of activity. Although ethanol did not change the shape and amplitude of action potentials, unit specific effects were found. The combined application of ethanol and fluoxetine was additive. Ethanol did not potentiate the effect of fluoxetine.
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The Nineteenth Century Oboe Concertino: An Overview of its Structure with Two Performance Guides

The Nineteenth Century Oboe Concertino: An Overview of its Structure with Two Performance Guides

Date: August 2002
Creator: Murray, Lauren Baker
Description: Music written for oboe and orchestra in the nineteenth century falls into three categories: Classical Concerto, Opera Fantasy, and Concertino. The classical, or standard, three movement, sonata-ritornello format was only sparingly used. Instead, composers chose more the experimental forms of the Opera Fantasy and Concertino. The Opera Fantasy was used as a way for oboe players to play popular opera arias of the time, while showcasing their virtuosity and expression. It is in the Concertino where composers expanded the oboe repertoire to its highest form in the nineteenth century, experimenting with structure, and using the oboe to the height of its expressive powers. In addition to discussion on the Concertino in general, performance guides have been provided for two concertinos, Concertino for Oboe and Winds, by Carl Maria von Weber and Concertino for Oboe and Orchestra, Op. 18, by August Klughardt. Information is provided regarding composer biography, compositional/historical perspective, technical and stylistic considerations, and structure. By examining the two very different pieces, one from the beginning of the nineteenth century and one from the end, the evolution of the Concertino can be seen, as well as gaining an understanding of the wide variety of repertoire written for the oboe in ...
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Occupational therapy academic program faculty attitudes toward tenure as measured by the Tenure Attitude Scale

Occupational therapy academic program faculty attitudes toward tenure as measured by the Tenure Attitude Scale

Date: August 2002
Creator: Brown, Diane Peacock
Description: This study explored attitudes of occupational therapy faculty toward tenure and selected alternatives to tenure. A survey method was employed, and the Tenure Attitude Survey Instrument, (TASI), was created for use in the study. Additionally, a questionnaire sought information regarding respondents' rank, tenure and administrative status, institutional type, and years in academia. Participants were accredited occupational therapy professional program faculty who identified their primary work setting as "Academic" on the 2000-2001 American Occupational Therapy Association membership survey. Factor analysis of 577 surveys examined the structure of scores on the TASI, and the instrument consisted of 4 scales, and 18 items, as follows: Scale One: Attitude toward academic freedom and job security protection, 7 items; Scale Two: Attitude toward tenure in general, 6 items; Scale Three: Attitude toward stop-the-tenure clock provisions, 2 items; and Scale Four: Attitude toward post-tenure review, 3 items. Cronbach's alpha was conducted, as follows: TASI overall alpha = .7915; Scale 1 alpha = .7884; Scale 2 alpha = .8420; Scale 3 alpha = .7020; Scale 4 alpha = .4229. Proportional analysis showed that most respondents were full time faculty (88.1%); taught full time at public institutions (52.8%); were tenured or tenure-track (55.5%); had no administrative duties (70.5%); ...
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A Performance Guide to Tomas Svoboda's Duo Concerto for Trumpet and Organ, Op. 152

A Performance Guide to Tomas Svoboda's Duo Concerto for Trumpet and Organ, Op. 152

Date: August 2002
Creator: Murray, Robert
Description: The Duo Concerto Trumpet and Organ, Op.152 by Tomas Svoboda was written in memory of and commissioned by the friends of the late Richard Thornburg, second trumpet of the Oregon Symphony. Through the use of primary sources, Tomas Svoboda, composer and organist at the premiere, and Fred Sautter, principal trumpet of the Oregon Symphony and trumpeter at the premiere, the performance guide illuminates the piece with a discussion of five different topics. Chapter 2 of the guide reveals the circumstances of the commission and the initial compositional process. Chapter 3 discusses the performance history of the concerto, including the premiere. Chapter 4 provides analytical insights with programmatic titles accompanying the formal layout of the piece. Chapter 5 presents the piece from the standpoint of performance preparation. Chapter 6 concludes the guide with final thoughts of the composer, Tomas Svoboda. The guide provides the performer studying this piece the historical context of the concerto and highlights programmatic elements of the piece not apparent in its published form.
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Performing the Trumpet works of Donald Erb; A Guide to Preparation, Interpretation and Practices: A Lecture Recital, Together with Three Recitals of Selected Works by Purcell, Hindemith, Holmes, Friedman, Koetsier and Others

Performing the Trumpet works of Donald Erb; A Guide to Preparation, Interpretation and Practices: A Lecture Recital, Together with Three Recitals of Selected Works by Purcell, Hindemith, Holmes, Friedman, Koetsier and Others

Date: August 2002
Creator: Spencer, David W.
Description: This study is a guide to the performer on practices associated with the trumpet music of Donald Erb. It examines the following solo and duo compositions for trumpet: the as yet unpublished Sonatina for Trumpet and Piano (1954); Four Duets for Trumpets (1960); Diversion for Two for trumpet & percussion (1966); Concerto for Trumpet and Orchestra (1980); Remembrances for two trumpets (1994); and Dance, You Monster, To My Soft Song for solo trumpet (1998). A history of each composition and information concerning the performers who premiered them are documented. An examination of particular harmonic, melodic and rhythmic elements found frequently in these pieces follow. The pieces are further assessed for difficulty through an investigation of extended technical demands, range, endurance and articulation. Additional discussion focuses on the use of mutes, tempos and dynamics as well as suggestions for the preparation and performance of these works. The dissertation concludes with a review of Donald Erb's legacy as a composer and teacher. A comprehensive discography and complete list of Mr. Erb's compositions are included in appendices.
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Peter Lieberson's First Piano Concerto:    A Buddhist-inspired poetic vision realized through twelve-tone language, other contemporary compositional techniques, together with three recitals of works by Bach, Chopin, Mozart, Albéniz, Grieg, Ginastera and Paderecki

Peter Lieberson's First Piano Concerto: A Buddhist-inspired poetic vision realized through twelve-tone language, other contemporary compositional techniques, together with three recitals of works by Bach, Chopin, Mozart, Albéniz, Grieg, Ginastera and Paderecki

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Date: August 2002
Creator: Méndez-Flanigan, Maria Gisela
Description: The main objective of this document is to explore the life and spiritual convictions of composer Peter Lieberson, and the creation of his Piano Concerto. Lieberson is a sought after composer who has won many awards and commissions. His works have been premiered and performed by some of the best musical artists of the late twentieth- and early twenty-first-century, such as Peter Serkin, Emmanuel Ax, Yo-Yo Ma, and Pierre Boulez. This study is divided into six chapters. After the Introduction, a biographical summary of Peter Lieberson's life, his spiritual beliefs and compositional style is presented. Chapter II contains background information on the Piano Concerto, along with biographical sketches of Peter Serkin, for whom the work was written, and Seiji Ozawa, music director of the Boston Symphony Orchestra and conductor of both the premier performance and Serkin's recording of the piece. Chapter III is a selective survey of the compositional techniques used in Lieberson's Concerto, in terms of the application of twelve-tone theory and the resulting octatonic, pentatonic, and whole-tone scales. Chapter IV introduces a general overview of the influence of Buddhism as a source of inspiration in the Piano Concerto. Chapter V examines aspects of performance practice issues. Chapter VI ...
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