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- Temporally Correct Algorithms for Transaction Concurrency Control in Distributed Databases
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Many activities are comprised of temporally dependent events that must be executed in a specific chronological order. Supportive software applications must preserve these temporal dependencies. Whenever the processing of this type of an application includes transactions submitted to a database that is shared with other such applications, the transaction concurrency control mechanisms within the database must also preserve the temporal dependencies. A basis for preserving temporal dependencies is established by using (within the applications and databases) real-time timestamps to identify and order events and transactions. The use of optimistic approaches to transaction concurrency control can be undesirable in such situations, as they allow incorrect results for database read operations. Although the incorrectness is detected prior to transaction committal and the corresponding transaction(s) restarted, the impact on the application or entity that submitted the transaction can be too costly. Three transaction concurrency control algorithms are proposed in this dissertation. These algorithms are based on timestamp ordering, and are designed to preserve temporal dependencies existing among data-dependent transactions. The algorithms produce execution schedules that are equivalent to temporally ordered serial schedules, where the temporal order is established by the transactions' start times. The algorithms provide this equivalence while supporting currency to the extent out-of-order commits and reads. With respect to the stated concern with optimistic approaches, two of the proposed algorithms are risk-free and return to read operations only committed data-item values. Risk with the third algorithm is greatly reduced by its conservative bias. All three algorithms avoid deadlock while providing risk-free or reduced-risk operation. The performance of the algorithms is determined analytically and with experimentation. Experiments are performed using functional database management system models that implement the proposed algorithms and the well-known Conservative Multiversion Timestamp Ordering algorithm.
- Teen ages: Youth market romance in Hollywood teen films of the 1980s and 1990s
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This thesis examines the differences between teen romantic comedy films marketed to Generation X teenagers in the 1980s and Generation Y teenagers in the 1990s, focusing on the presentation of gender roles, consumptive behavior, and family. The 1980s films are discussed within the social context of the Reagan era and the conservatism of the New Right. The 1990s films are examined as continuing a conservative sensibility, but they additionally posit consumption as instrumental to achieving an idealized romance. Romantic comedy is traditionally a conservative genre, but these films illustrate female liberation through consumption. The source of difference between the cycles of teen romantic comedy is attributed to the media's attempt to position Generation Y teenagers as ideal consumers.
- A Collapsing Result Using the Axiom of Determinancy and the Theory of Possible Cofinalities
- Assuming the axiom of determinacy, we give a new proof of the strong partition relation on ω1. Further, we present a streamlined proof that J<λ+(a) (the ideal of sets which force cof Π α < λ) is generated from J<λ+(a) by adding a singleton. Combining these results with a polarized partition relation on ω1
- Isolation and analysis of cotton genomic clones encompassing a fatty acid desaturase (FAD2) gene
- Polyunsaturated fatty acids are major structural components of plant chloroplast and endoplasmic reticulum membranes. Two fatty acid desaturases (designated FAD2 and FAD3) desaturate 75% of the fatty acids in the endoplasmic reticulum. The w -6 fatty acid desaturase (FAD2) may be responsible for cold acclimation response, since polyunsaturated phospholipids are important in helping maintain plant viability at lowered temperatures. To study regulation of FAD2 gene expression in cotton, a FAD2 gene was isolated from two genomic libraries using an Arabidopsis FAD2 hybridization probe and a cotton FAD2 5¢ -flanking region gene-specific probe, respectively. A cotton FAD2 gene was found to be in two overlapping genomic clones by physical mapping and DNA sequencing. The cloned DNA fragments are identical in size to cotton FAD2 genomic DNA fragments shown by genomic blot hybridization. The cotton FAD2 coding region has 1,155 bp with no introns and would encode a putative polypeptide of 384 amino acids. The cotton FAD2 enzyme has a high identity of 75% with other plant FAD2 enzymes. The enzyme has three histidine-rich motifs that are conserved in all plant membrane desaturases. These histidine boxes may be the iron-binding domains for reduction of oxygen during desaturation. To confirm that this FAD2 enzyme is functional, a plasmid construct containing the cotton FAD2 coding region was transformed into Saccharomyces cerevisiae. The transformed yeast cells were able to catalyze the conversion of oleic acid (C18:1) into linoleic acid (C18:2). The FAD2 gene contains an intron of 2,967 bp in its 5¢ -flanking region, 11 bp upstream from the initiation codon. The intron could be essential for transcriptional regulation of FAD2 gene expression. Several putative promoter elements occur in the 5¢ -flanking region of this gene. A potential TATA basal promoter element occurs at 41 bp upstream from the cap site. Two presumptive helix-loop-helix (bHLH) motifs that may be seed-specific promoter elements are located at 109 bp and 135 bp upstream from the potential cap site.
- Unique applications of cultured neuronal networks in pharmacology, toxicology, and basic neuroscience
- This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related compounds, and reveal information about their probable physiological effects that are not attainable through biochemical characterization alone. Chapter 2 shows how neuronal networks may be used to classify and characterize an unknown compound. The compound, trimethylol propane phosphate (TMPP) elicited changes in network activity that resembled those induced by bicuculline, a known epileptogenic. Further work determined that TMPP produces its effects on network activity through a competitive inhibition of the GABAA receptor. This demonstrates that neuronal networks can provide rapid, reliable warning of the presence of toxic substances, and from the manner in which the spontaneous activity changes provide information on the class of compound present and its potential physiological effects. Additional simple pharmacological tests can provide valuable information on primary mechanisms involved in the altered neuronal network responses. Chapter 3 explores the effects produced by a radical simplification of synaptic driving forces. With all synaptic interactions pharmacologically limited to those mediated through the NMDA synapse, spinal cord networks exhibited an extremely regular burst oscillation characterized by a period of 2.9 ± 0.3 s, with mean coefficients of variation of 3.7, 4.7, and 4.9 % for burst rate, burst duration, and inter-burst interval, respectively (16 separate cultures). The reliability of expression of this oscillation suggests that it may represent a fundamental mechanism of importance during periods of NMDA receptor dominated activity, such as embryonic and early postnatal development. NMDA synapse mediated activity produces a precise oscillatory state that allows the study of excitatory-coupled network dynamics, burst mechanisms, emergent network properties, and structure-function relationships.
- Language Policy, Protest and Rebellion
- The hypothesis that language discrimination contributes to protest and/or rebellion is tested. Constitutional language policy regarding administrative/judicial, educational and other matters is measured on three separate scales developed for this study; the status of each minority group's language under its country's policy is measured by another set of scales. Protest and rebellion variables are taken from Gurr's Minorities at Risk study. Findings include an indication that group language status contributes positively to protest and rebellion until a language attains moderate recognition by the government, at which point status develops a negative relationship with protest and rebellion, and an indication that countries with wider internal variations in their treatment of language groups experience higher levels of protest and rebellion on the part of minority groups.
- Distribution and Probable Sources of Nitrate in the Seymour Aquifer, North Central Texas, USA
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This study utilized GIS and statistical methods to map the spatial variability of nitrate and related groundwater constituents in 30 counties above the Seymour Aquifer, analyze temporal patterns of nitrate pollution, identify probable sources of pollution, and recommend water development strategies to minimize exposure to nitrate and reduce future aquifer contamination. Nitrate concentrations in excess of 44 mg/L (US EPA limit) were commonly observed in the Seymour Aquifer region, especially in the central agricultural belt. Data indicated that this is an ongoing problem in the Seymour Aquifer and that agricultural activity and rural septic systems are the likely sources of the nitrate. Inconclusive results emphasized the need for a more comprehensive spatial and temporal water quality monitoring.
- Intentions and Implementation of the Professional Development and Appraisal System in Texas
- The purpose of this study was to describe the intentions of the designers of the Professional Development and Appraisal System (PDAS) in Texas and the perceptions of teachers regarding its implementation. Information for the study was gathered in two phases using two methodologies. The first was a semi-structured interview with four expert informants instrumental in the design and implementation of the PDAS at the state level. The second component of the study was conducted with teachers using a 37-item Likert survey. The population for this phase of the study was 150 elementary and 150 secondary teachers chosen randomly from three school districts in North Central Texas. The districts were selected to represent a variety of sizes in regard to student population and represent diverse student population characteristics and socioeconomic levels. Data from the semi-structured interviews and the returned surveys were analyzed to determine the designers' intentions and areas of emphasis and to describe the alignment the teachers' perceptions and the designers' intentions. Quantitative data gathered from the surveys were analyzed using descriptive statistics as well as a correlation and function analysis and analysis based on a Cronbach alpha coefficient. The analysis of data revealed the following: 1. Teachers perceived that the implementation of the PDAS has a high level of effect in the areas of learner-centered instruction; classroom management; support for all students; the professional growth of teachers; communication; learning application; and, TAAS improvement. 2. Teachers' perceptions were not affected by years of experience. 3. Teachers' perceptions were not affected by their field of instruction. One implication of this study is that the final design represents the intentions of designers, although the area of student achievement is not weighted as heavily in teachers' evaluations as was originally intended. Furthermore, education leaders in Texas may conclude that teachers perceive a high level of impact upon their classroom practices as a result of implementation of the PDAS instrument. If future research reveals that the perceived impact is accurate and that classroom practices of teachers did change as a result of the instrument's implementation to the degree perceived, then this is a model for policy implementation at the state level that is extremely effective. Furthermore, additional researchers may investigate the link between classroom practices and student achievement. This research study is a first step toward describing effective, replicable practices.
- An exploration of parental sensitivity and child cognitive and behavioral development.
- The current study attempted to show the relationship of paternal sensitivity and maternal sensitivity and their possible influences on child cognitive and behavioral development. This study used data collected as part of the National Institute for Child Health and Human Development (NICHD) Study of Early Child Care, which is a longitudinal, multi-site study. Correlation and regression analyses were computed to examine relationships between the variables at child age 6 and 36 months. Results indicated paternal sensitivity was a significant positive predictor of child cognitive abilities and a negative predictor of both fathers' reports of children's externalizing and internalizing behaviors. Maternal sensitivity was a significant negative predictor of mothers' reports of children's externalizing behaviors. Interpretations of these results and directions for future research are discussed.
- "This Beautiful Evil": The Connection between Women, the Natural World, Female Sexuality, and Evil in Western Tradition
- Female archetypes reflect a social construction of reality, expressing expected modes of behavior, beliefs, and assumptions about women and are reinforced by repetition of common patterns and themes. Often female archetypes take on the physical characteristics of animals, commune with nature, engage in sexual promiscuity, and possess special powers to bewitch and control men into doing their bidding. Four prevalent archetypes include: the Predatory Woman, who with her bestial nature becomes the hunter of men; the Sacrificial Woman, who dutifully negates herself for the sake of men; the Bad Mother, who is cold, unnatural, and challenges men; and les enfants terrible seductive girl-women who at once tempt and torment men. This research traces the development and evolution of female archetypes and explores how images of women, nature, sexuality, and evil are structured within a cultural framework of Western tradition: myths and folktales, religious, philosophical, and scientific works, and film.
- Virtual teams: The relationship between organizational support systems and effectiveness
- This study investigates the effects of eight organizational support systems on virtual team effectiveness in five areas: communication, planning tasks and setting goals, solving problems and making decisions, resolving conflict, and responding to customer requirements. One hundred and eighty surveys were sent to information technology managers and collaborative team members, representing 43 companies. The results indicated that developing new roles for IT professionals and senior managers significantly increased virtual team effectiveness in several areas. The findings support the theory that organizations that utilize virtual teams must create high-level structures, policies, and systems to support the teams and the information tools they use.
- Age-Dependent Effects Of Chronic GABAA Receptor Blockade In Barrel Cortex
- GABAA receptor binding is transiently increased in rat whisker barrels during the second postnatal week, at a time when neurons in the developing rat cortex are vulnerable to excitotoxic effects. To test whether these GABAA receptors might serve to protect neurons from excessive excitatory input, polymer implants containing the GABAA receptor antagonist bicuculline were placed over barrel cortex for a 4-day period in young (postnatal days 8 - 12) and adult rats. In the cortex of young, but not adult rats, the chronic blockade of GABAA receptors resulted in substantial tissue loss and neuron loss. The greater loss of neurons in young rats supports the hypothesis that a high density of GABAA receptors protects neurons from excessive excitatory input during a sensitive period in development.
- Jules Massenet's Musical Prosody Focusing on His Eight Song Cycles And A Collection, Expressions Lyriques: A Lecture Recital, Together with Recitals of Selected Works of W. A. Mozart, F. Schubert, C. Debussy, R. Strauss, D. Argento, V. Bellini, J. Marx, W. Walton, C. Gounod, A. Scarlatti, G. Fauré, J. Rodrigo, H. Wolf, and Others
- Jules Massenet's mélodies feature a distinct vocal treatment regarding musical prosody through his eight song cycles, including Poëme d'Avril, Poëme Pastoral, Poëme du Souvenir, Poëme d'Amour, Poëme d'Hiver, Poëme d'un Soir, and Quelques Chansons Mauves, and a collection, Expressions Lyriques. These mélodies show the influence of the trend of salon music and the high-level poetry from the poetic movements of romanticism, Parnassianism, and symbolism. This study deals with Massenet's mélodies relating to the prosody idea, which is conspicuous in his vocal treatment. His melodic styles feature four distinct aspects of vocal treatment including lyrical, recitative or parlando, melodramatic, and déclamation rhythmée, and represent the idea of musical prosody of phonetic, syntactic, and semantic aspects. Massenet's other musical idioms such as harmony, form, and piano treatment, are also closely related to the prosody matter as a semantic aspect, reinforcing the poetic mood and content. In this study, each melodic style related to French versification is examined in detail. The musical analysis regarding the other musical idioms on selected examples presents the semantic feature of prosody idea. The brief review of French versification and opinions regarding the performance are included. Massenet's contribution to the genre of mélodie, with the prose melody and treatment of piano as an equal partner of voice line, is clearly demonstrated. With this contribution, Massenet should be recognized as the most influential composer to the climatic time of French mélodie led by Fauré, and Debussy, and Duparc.
- The Stabat Mater of Herbert Howells: The Agony and the Ecstasy
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Herbert Howells composed three large works for chorus and orchestra: a requiem (Hymnus Paradisi), Latin mass (Missa Sabrinensis) and finally a Stabat Mater. Writings, performances and recordings of the Stabat Mater, however, have been few. As the Stabat Mater is believed to be the culmination of his musical prowess, it is important to bring this major work to light. Chapter 1 begins with a brief introduction to Herbert Howells, then continues as a brief biographical sketch. Howells's life is discussed from birth, as organ scholar, student at the Royal College of Music, his teaching professorship at the same institution, and important compositions by decade until his death. Chapter 2 is an overview of the Hymnus Paradisi and Missa Sabrinensis. The chapter gives historical information on each work, including reasons for commission, dates of composition and performance, orchestration and choral composition, type of soloists, conductor and recordings. Chapter 3 is an in depth study of the Stabat Mater. The chapter includes reasons for the genesis of the work, current and past events that affected the composition, musical influences, and the death of his son Michael Kendrick Howells. A second section to this chapter addresses the text of the Stabat Mater, including the history of the poem, liturgical use from the 11th century to the present, the rhythmic scheme of the poem, and variant stanzas used in the Howells's setting. Chapter 4 is a thorough musical analysis of the Stabat Mater. After a short introduction explaining the architecture of the work as a whole, each of seven movements is examined, including the introduction, main themes, musical elements and use of Latin text. A concluding final chapter restates the importance of Herbert Howells as a composer in the British musical renaissance of the 20th century, in addition to a supposition that this final large orchestral/choral work be considered the culmination of his life's work.
- Riparian Forest Width and the Avian Community in a Greenbelt Corridor Setting
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The forest avian community of the Ray Roberts Greenbelt (Denton Co., Texas) was characterized for two years using point count station sampling, from fall 1998 to summer 2000. Richness data for both breeding seasons were correlated with two-spatial metrics: width of the riparian forest and distance to the nearest edge. There were significant correlations between forest interior species richness and both spatial metrics, for both breeding seasons. Based on these data, a minimum riparian forest width threshold of 400-meters is suggested to provide habitat for forest interior species, which have lost considerable habitat through forest fragmentation. Partners in Flight breeding bird priority concern scores were used to create a habitat priority index for the Trinity River bottomland hardwood forest system
- A Qualitative Research Study of How Extended Field Experience Prepares Special Education Teachers of Students with Emotional and Behavioral Disorders
- A well-prepared and qualified special education teacher is crucial to the performance of students with emotional and behavioral disorders (EBD). The prominent educators and federal government encourage the use of extended field experiences in preparing qualified special education teachers. The study examined the strengths and weaknesses of extended field experience in terms of the perceptions of the prospective teachers and teachers of students with EBD. Both individual interviews and a focus group were used to collect data. The results revealed that extended field experience benefits prospective teachers in showing the reality of the teachers' world, self-motivation assessment, and professional development. However, there were some improvements that could be made, including more placement selections and more practical knowledge.
- Automated Low-cost Instrument for Measuring Total Column Ozone
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Networks of ground-based and satellite borne instruments to measure ultraviolet (UV) sunlight and total column ozone have greatly contributed to an understanding of increased amounts of UV reaching the surface of the Earth caused by stratospheric ozone depletion. Increased UV radiation has important potential effects on human health, and agricultural and ecological systems. Observations from these networks make it possible to monitor total ozone decreases and to predict ozone recovery trends due to global efforts to curb the use of products releasing chemicals harmful to the ozone layer. Thus, continued and expanded global monitoring of ozone and UV is needed. However, existing automatic stratospheric ozone monitors are complex and expensive instruments. The main objective of this research was the development of a low-cost fully automated total column ozone monitoring instrument which, because of its affordability, will increase the number of instruments available for ground-based observations. The new instrument is based on a high-resolution fiber optic spectrometer, coupled with fiber optics that are precisely aimed by a pan and tilt positioning mechanism and with controlling programs written in commonly available software platforms which run on a personal computer. This project makes use of novel low-cost fiber optic spectrometer technology. A cost advantage is gained over available units by placing one end of the fiber outdoors to collect sunlight and convey it indoors, thereby allowing the spectrometer and computer to be placed in a controlled environment. This reduces the cost of weatherproofing and thermal compensation. Cost savings also result from a simplified sun targeting system, because only a small pan and tilt device is required to aim the lightweight fiber optic ends. Precision sun-targeting algorithms, optical filter selection, and software to derive ozone from spectral measurements by the spectrometer are a major contribution of this project. This system is a flexible platform which may be adapted to study other atmospheric constituents such as sulfur dioxide, nitrous oxides, and haze.
- Mechanical Properties of Polymer Modified Mortar
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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 hydration, and to prove Ohama's theory of network structure.
- The impact of US-China relations on Taiwan's military spending (1966-1992).
- Previous research has shown that Taiwan's military spending is affected either by China's military buildup or the US's military pipeline. This study investigates whether it is also true an ongoing US-China relationship has dynamic effects. Three major findings are obtained from the statistical analyses. First and foremost, the level of US-China conflict has a contemporaneous positive effect on Taiwan's military spending. Second, the analyses also indicate that the volatility of US-China relations has negative effects on Taiwan's military spending. This finding suggests that instability in US-China relations will prompt Taiwan to decrease its military spending due to a higher amount of perceived security on the one hand, and Taiwan wants to avoid further provoking China on the other. Third, analyses indicate that an error correction model fares better than a simple budgetary incremental model in explaining the re-equilibrating effects of GNP growth on Taiwan's military spending. Overall, the results demonstrate the interplay of domestic and international constraints and may help to predict what will be the expected military spending when Taiwan's economy changes. I suggest that Taiwan's military spending is likely to be influenced by US-China relations as well as by foreign investment and domestic economic constraints as long as the United States policy toward the Taiwan problem remains unchanged.
- Kinetic Studies of Hydroxyl and Hydrogen Atom Reactions
- Gas phase kinetics of the reactions involving hydroxyl radical and hydrogen atom were studied using experimental and ab initio theoretical techniques. The rate constant for the H + H2S reaction has been measured from 298 to 598 K by the laser photolysis/resonance fluorescence (LP-RF) technique. The transition state theory (TST) analysis coupled with the measurements support the suggestion that the reaction shows significant curvature in the Arrhenius plot. The LP-RF technique was also used to measure the rate constant of the H + CH3Br reaction over the temperature range 400-813 K. TST and density functional theory (DFT) calculations show that the dominant reaction channel is Br-abstraction. The reaction H + CF2=CF-CF=CF2 was first studied by flash photolysis/resonance fluorescence (FP-RF) method. The experiments of this work revealed distinctly non-Arrhenius behavior, which was interpreted in terms of a change in mechanism. DFT calculations suggest that the adduct is CF2H-CF•-CF=CF2. At lower temperatures a mixture of this molecule and CF2•-CFH-CF=CF2 is likely. The theoretical calculations show that H atom migrates in the fluoroethyl radicals through a bridging intermediate, and the barrier height for this process is lower in the less fluorinated ethyl radical. High level computations were also employed in studies of the rate constants of OH + chloroethylenes reactions. VTST calculations indicate that, except the reaction of OH + C2Cl4, these reactions present a complex behavior. For OH + C2Cl4, conventional TST calculation shows a simple positive temperature-dependence behavior.
- The Use of Genetic Polymorphisms and Discriminant Analysis in Evaluating Genetic Polymorphisms as a Predictor of Population
- Discriminant analysis is a procedure for identifying the relationships between qualitative criterion variables and quantitative predictor variables. Data bases of genetic polymorphisms are currently available that group such polymorphisms by ethnic origin or nationality. Such information could be useful to entities that base financial determinations upon predictions of disease or to medical researchers who wish to target prevention and treatment to population groups. While the use of genetic information to make such determinations is unlawful in states and confidentiality and privacy concerns abound, methods for human “redlining” may occur. Thus, it is necessary to investigate the efficacy of the relationship of certain genetic information to ethnicity to determine if a statistical analysis can provide information concerning such relationship. The use of the statistical technique of discriminant analysis provides a tool for examining such relationship.
- 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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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 provides conclusions. The aim of this study is to further establish Peter Lieberson's stature as an important modern American composer. It is hoped that this study will encourage further research and interest in his works.
- La Primavera: Concertino for English Horn and Chamber Orchestra
- La Primavera: Concertino for English Horn and Chamber Orchestra is a work in a traditional chamber orchestra instrumentation: single woodwinds (flute, oboe, clarinet, and bassoon), two French horns, trumpet, timpani and strings. A through-composed work of 14 minutes in duration, the Concertino is conceptually based on the idea that spring is not the first of the seasons, but rather the last. As a result, all of its motivic materials are organically linked to one another, and function as paired forces that struggle for supremacy. The introduction of the third motive functions as a motivic synthesis, since it contains intrinsic elements of previous motives. There are several important compositions based on the topic of the seasons among them we find: Vivaldi's Concerto Grosso Le Quatro Staggione, Haydn's oratorio The Seasons, and Piazzola's chamber work Las Estaciones. While researching this topic, the conceptual dilemma of spring as the last season was considered. This became a turning point in the compositional process strong enough to consider the spring as a singular topic of interest. The analysis of this work through Derrida's Deconstruction theory first came to me while reading Rose Rosengerd Subotnick's Deconstructive Variations: Music and Reason in Western Society. The Linguistic approach, was inspired in part by Leonard Bernstein's lecture “The Unanswered Question,” and Jean J. Nattiez's Music and Discourse: Toward a Semiology of Music.
- The Effects of Selective Serotonin Reuptake Inhibitors (SSRI) on Auditory Measures in Women
- This study examined the relationship between selective serotonin reuptake inhibitor (SSRI) medication and auditory measures in clinically depressed women. Experimental subjects were tested in both a medicated and unmedicated condition. Experimental subjects were compared to a normal control group; additionally intrasubject comparison was made within the experimental group. Test measures included: audiometry, tympanometry, otoacoustic emissions, uncomfortable loudness level, masking level difference, SCAN-A, Synthetic Sentence Identification (SSI), and the low predictability section of the Revised Speech in noise (RSPIN). The unmedicated group scored significantly less favorably than the control group on the following tests; SCAN-A (composite, filtered words, and auditory figure ground), R-SPIN (0MCR condition in both the right and left ears). Additionally, the unmedicated group scored significantly less favorably than the medicated group on the SSI (-20MCR condition right ear only) and of the R-SPIN (0MCR condition right ear only). Other test measures indicated consistent trends but did reach significance.
- An investigation of the current status of fund raising activities and training within student affairs divisions in Texas colleges and universities.
- The primary focus of this study was to discover the depth of involvement with fundraising by student affairs professionals in Texas. It sought to determine the predominance of chief student affairs officers trained in development and the types of training that they received. Cooperation between student affairs divisions and development offices was also studied and whether there was a correlation between a cooperative relationship and the number of successful fundraising goals. This study includes a review of related literature on student affairs fundraising, a description of the methodology, results of the survey, conclusions, implications, and recommendations that may assist in future decision-making concerning future involvement in fundraising. The surveys were mailed to 149 four-year (public and private) institutions and two-year public institutions in Texas. The senior staff members of both the student affairs office and development office were asked to complete a survey. There was a 60.7% return rate consisting of responses from 72 development offices and 95 student affairs offices for a total of 167 usable responses. The study found that 59% of the student affairs officers had some formal training and/or on the job training. Involvement in fundraising was reported by 62.1% of the chief student affairs officers. Eighteen percent reported that they employed a development officer exclusively for student affairs fundraising, and another 30% had a development officer assigned to student affairs. Most development officers and student affairs officers perceived the other officer as cooperative rather than competitive in raising funds. Recommendations from this study include studying community college fundraising structures separately for more depth, conducting qualitative interviews with student affairs development officers, making a comparison of student affairs offices that have full-time development officers, and comparing the differences in fundraising success between development officers and chief student affairs officers. Recommendations for the professions include resource development training for student affairs officers and student affairs education for development officers.
- Smoothing the information seeking path: Removing representational obstacles in the middle-school digital library.
- Middle school student's interaction within a digital library is explored. Issues of interface features used, obstacles encountered, search strategies and search techniques used, and representation obstacles are examined. A mechanism for evaluating user's descriptors is tested and effects of augmenting the system's resource descriptions with these descriptors on retrieval is explored. Transaction log data analysis (TLA) was used, with external corroborating achievement data provided by teachers. Analysis was conducted using quantitative and qualitative methods. Coding schemes for the failure analysis, search strategies and techniques analysis, as well as extent of match analysis between terms in student's questions and their search terms, and extent of match analysis between search terms and controlled vocabulary were developed. There are five chapters with twelve supporting appendixes. Chapter One presents an introduction to the problem and reviews the pilot study. Chapter Two presents the literature review and theoretical basis for the study. Chapter Three describes the research questions, hypotheses and methods. Chapter Four presents findings. Chapter Five presents a summary of the findings and their support of the hypotheses. Unanticipated findings, limitations, speculations, and areas of further research are indicated. Findings indicate that middle school users interact with the system in various sequences of patterns. User groups' interactions and scaffold use are influenced by the teacher's objectives for using the ADL. Users preferred to use single word searches over Boolean, phrase or natural language searches. Users tended to use a strategy of repeating the same exact search, instead of using the advanced scaffolds. A high percent of users attempted at least one search that included spelling or typographical errors, punctuation, or sequentially repeated searches. Search terms matched the DQ's in some instantiation 54% of all searches. Terms used by the system to represent the resources do not adequately represent the user groups' information needs, however, using student generated keywords to augment resource descriptions can have a positive effect on retrieval.
- Lucca in the Signoria of Paolo Guinigi, 1400-1430
- This study analyzes the once great medieval Tuscan capital of Lucca's struggle for survival at the beginning of the fifteenth century. This was the age of the rise of regional states in Italy, and the expansionistic aims of Milan, Florence and others were a constant challenge to city-states such as Lucca which desired a political and cultural status quo. Yet, it was a challenge that was successfully met; unlike Pisa, Siena, Perugia, and various other major Tuscan cities, Lucca did not succumb to Milanese or Florentine aggression in the early Quattrocento. Why it did not is a major topic of discussion here. One of the means in which the Lucchese faced the new political and military realities of the time was the establishment of a monarchial system of government in the signoria of Paolo Guinigi (r. 1400-1430). The Guinigi Signoria was not characterized by the use of intimidation and violence, but rather by clientage, kinship and neighborhood bonds, marriage alliances, and the general consent of the people. Paolo garnered the consent of the people at first because his wealth allowed him to protect Lucca and its contado to a greater extent than would have been possible otherwise, and because of his family's long ties with the powerful Visconti of Milan; he held it later because he provided the city-state with capable leadership. This study extends the evidence of recent scholars that every Italian Renaissance city was unique based on its particular geography, alliances, civic wealth, and a number of other factors. Lucca in the period of Paolo Guinigi, a monarchy in the setting of one of the traditionally most republican cities of Italy, provides a most interesting example. “Civic humanism,” for example, has a decidedly different slant in Lucca than elsewhere, and is best exemplified in the figure of Giovanni Sercambi. This study also provides new perspectives from which to view Florence and Milan during the period of “crisis” at the beginning of the fifteenth century, and thus contributes to the mass of scholarship concerning the Baron thesis.
- A Computational Study on 18+δ Organometallics
- The B3LYP density functional has been used to calculate properties of organometallic complexes of Co(CO)3 and ReBr(CO)3, with the chelating ligand 2,3-bisphosphinomaleic anhydride, in 19- and 18-electron forms. The SBKJC-21G effective core potential and associated basis set was used for metals (Co/Re) and the 6-31G* basis set was used for all other elements. The differences of bond angles, bond distances, natural atomic charges and IR vibrational frequencies were compared with the available experimental parameters. The differences between the 19- and 18-electron systems have been analyzed. The results reveal that the 19th electron is mostly distributed over the ligand of 2,3-bisphosphinomaleic anhydride, although partially localized onto the metal fragment in 1 and 2*. Two different methods, IR-frequencies and natural atomic charges, were used to determine the value of δ. Present computed values of δ are compared with available experimental values, and predictions are made for unknown complexes.
- Establishing the utility of a classroom effectiveness index as a teacher accountability system.
- How to identify effective teachers who improve student achievement despite diverse student populations and school contexts is an ongoing discussion in public education. The need to show communities and parents how well teachers and schools improve student learning has led districts and states to seek a fair, equitable and valid measure of student growth using student achievement. This study investigated a two stage hierarchical model for estimating teacher effect on student achievement. This measure was entitled a Classroom Effectiveness Index (CEI). Consistency of this model over time, outlier influences in individual CEIs, variance among CEIs across four years, and correlations of second stage student residuals with first stage student residuals were analyzed. The statistical analysis used four years of student residual data from a state-mandated mathematics assessment (n=7086) and a state-mandated reading assessment (n=7572) aggregated by teacher. The study identified the following results. Four years of district grand slopes and grand intercepts were analyzed to show consistent results over time. Repeated measures analyses of grand slopes and intercepts in mathematics were statistically significant at the .01 level. Repeated measures analyses of grand slopes and intercepts in reading were not statistically significant. The analyses indicated consistent results over time for reading but not for mathematics. Data were analyzed to assess outlier effects. Nineteen statistically significant outliers in 15,378 student residuals were identified. However, the impact on individual teachers was extreme in eight of the 19 cases. Further study is indicated. Subsets of teachers in the same assignment at the same school for four consecutive years and for three consecutive years indicated CEIs were stable over time. There were no statistically significant differences in either mathematics or reading. Correlations between Level One student residuals and HLM residuals were statistically significant in reading and in mathematics. This implied that the second stage of the model was consistent for all students. Much is still unknown concerning teacher effect on student achievement, especially when confined to teacher activity within one school year. However, results indicate the utility of using statistical modeling of student achievement within the context of teacher accountability.
- And Drops of Rain Fall Like Tears: A Composition for Electroacoustic Music and Video
- And Drops of Rain Fall Like Tears is a composition for electroacoustic music with an optional ambient video component. The composition consists of a single movement electroacoustic work twenty-two minutes in duration. The piece creates an immersive sonic environment within the confines of a typical concert space, thereby recreating the powerful temper and subtle beauty of nature from different sonic perspectives. The paper is divided into four chapters, each discussing an element of the piece in detail. The introduction presents background information and compositional approach for the composition. Chapters 1 through 4 present detailed information related to the creation of both the electroacoustic music and video elements of the piece. Chapter 4 contains relevant information to the performance of the piece.
- Neuronal Network Analyses in vitro of Acute Individual and Combined Responses to Fluoxetine and Ethanol
- 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.
- Adolescent Psychopathy in an Adjudicated Male Population: The Role of Sensation Seeking, Impulsivity, and Externalizing Disorders
- Psychopathy, as conceptualized by Cleckley (1941), describes a constellation of psychological and behavioral correlates including superficial charm, untruthfulness, lack of remorse or shame, poor judgment, and failure to learn from experience. Based on Cleckley's initial work, Hare (1991) developed a two-factor model of psychopathy. The purpose of this study was to investigate the roles that sensation seeking, impulsivity, ADHD, conduct disorder, and oppositional defiant disorder have on adolescents classified as psychopaths. The participants consisted of 79 adjudicated male adolescents in a maximum-security facility. As hypothesized, adolescent male psychopaths had higher levels of sensation seeking, impulsivity, conduct disorder and oppositional defiant disorder. A discriminant function analysis found that sensation seeking, impulsivity, ADHD, Conduct Disorder, and Oppositional Defiant Disorder was moderately useful in classifying adolescent psychopathy. The results suggest that behavioral dysregulation is an important aspect of adolescent psychopathy. The relationship of these data to theories of adolescent psychopathy is discussed.
- Strategic Versus Sincere Behavior: The Impact of Issue Salience and Congress on the Supreme Court Docket
- The theory proposed here is that the Supreme Court behaves in a strategic manner at the agenda-setting stage in order to vote sincerely on the merits. To test this, I measure the impact issue salience and ideological distance between Congress and the Supreme Court has on the agenda. The results indicate that whether the Supreme Court behaves either sincerely or strategically depends on the policy area. The strategic nature of the Supreme Court at the agenda-setting phase may be in large part why some research shows that the Court behaves sincerely when voting on the merits. By behaving strategically at the agenda-setting phase, the Court is free to vote sincerely in later parts of the judicial process.
- The Piano as an Orchestra: The Accompanist and the Twentieth-Century Orchestral Reduction
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The musical developments of the 20th century have expanded the role of the accompanist. As the compositional output of our time increases, and the opportunity to perform as soloist with an orchestra diminishes, piano reductions of an orchestral score are becoming the most frequent vehicle for concerto performances of twentieth and twenty-first century instrumental literature. While the current state of research provides solid support to many accompanists, it is in the area of instrumental accompanying, especially with regard to the challenges of playing a reduction of an orchestral score with an instrumental soloist, that the lack of discourse becomes strikingly evident. It is the goal of this study to provide the instrumental accompanist with concrete, practical approaches and considerations in order to perform an orchestral reduction in a manner consistent with the integrity of the score. Problems such as identifying the represented orchestral instruments, delineating importance of musical lines, and basic uses and misuses of pedal, articulation, and rubato are discussed. The pianist is led through ways of deciphering and negotiating specific passages, in order to guide the accompanist through the possible pitfalls and challenges unique to many orchestral reductions. By focusing on twentieth century reductions, providing examples of problems and discussing ways to solve them, the pianist will able to apply these to any reduction encountered, not just those specifically illustrated here. These basic principles of discerning common problems and appropriately reconciling them are then applied in a more advanced form to Robert Nelson's Concertino for Baritone Saxophone (1996). Through commentary from the composer, and a comparison of the orchestral score to the reduced piano score, the accompanist will explore detailed techniques of performing this work in a manner that upholds the original “orchestral” intent of the music.
- Team performance: Using financial measures to evaluate the effect of support systems on team performance.
- Organizations invest in team-based systems in order to generate innovative practices that will give them a competitive edge. High-performing teams require training and other support systems to gain the skills they need as well as to create and maintain an environment conducive to their success. The challenge for managers is to make resource allocation decisions among investment alternatives to maximize team effectiveness and still ensure a financial return for company investors. This study has three objectives. The first objective is to investigate whether there is a positive relationship among organizational environment, team potency (the team's collective belief it will succeed) and team performance. Results indicate that the presence of four organizational support systems influences team potency and performance. These support systems are the Design and Measurement, Rewards, Training and Communications Systems. In addition, results indicate that team potency is a mediating variable between the Design and Measurement and Communications Systems and team performance. These results suggest that companies are able to influence team performance by investing in environmental support systems. The second objective is to examine whether team members and managers view the organizational environment differently. Results indicate that managers view the Training and Communications Systems as more important, while teams perceive the Design and Measurement System and the Rewards System to be more important to their success. Since the systems that team managers view as important may influence their investment decisions, these differences may suggest a resource alignment issue. Third, a measure of team effectiveness based on financial measures is introduced. Published literature emphasizes attitudinal, behavioral and operational measures of performance. A financial measure offers a method of evaluating performance that is similar to methods used in capital budgeting and may be consistently applied across different types of teams with different purposes. The data collection process was performed by persons external to the team and covered a 12-month period. This method led to a loss of information and did not accurately portray team performance. However, the teams that were successful in calculating project savings were different types of teams from both manufacturing and service industries. This result is encouraging and warrants further investigation.
- Synthesis of Crown Ether/Ammonium Salt for Electron Transfer Study
- The theoretical model of Beratan and Onuchic predicts a large attenuation of ET rates through hydrogen bonds; however, the effect of individual hydrogen bond on electron transfer reaction has not been systematically studied. The organic complexes in this study are a series of crown ether/ammonium salt, which incorporate a redox partner on each component of the complex. The dimethoxynaphthalene redox donor was attached to the crown ether and a series of ammonium salts was synthesized which bear substituted quinone and naphthoquinone acceptor. The complexes characterization and preliminary electron transfer rate measurement were completed with UV/Vis and steady-state emission spectroscopy.
- Mechanisms of rapid receptive field reorganization in rat spinal cord
- 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 consistent with other studies. Following the injection, the original RFs were completely silenced (46%) or remained responsive (54%).
- Reflections of Other/Reflections of Self
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This Thesis collection contains a critical preface and five stories. The preface, “Reflejos y Reflexiones” (translated: Images and Thoughts), addresses the issues of writing the cultural or gendered Other; these issues include methodology, literary colonialism, a dialogue between works, and creating distance through defamiliarizing the self. “Perennials” is the story of Noemi Tellez, an immigrant to the U.S. who must choose between working and taking care of her family. In “Load Bearing” Luis, the eldest child, faces his family and friends on one of his last days before moving away to college. “La Monarca” deals with Lily's, the youngest daughter, struggle to mediate a place between her friends and her family. In “Reflections in the River,” Arabela, the second youngest, faces the ghost of an unwanted pregnancy and La Llorona. “La Cocina de Su Madre” is the story of Magda, the oldest daughter, and her own teenage girl, Natalia, as they attempt to find themselves in a new town after moving a thousand miles from home.
- Leadership Frames of Female Presidents of American Research Universities
- This study used case studies to examine the leadership frames of female presidents of four-year, public and private, coeducational research institutions both from the Intensive and Extensive Carnegie classifications within the United States. The population (N=30) surveyed was sent the Leadership Orientation Questionnaire (Self) developed from the previous research conducted by Lee Bolman and Terrance Deal. The Bolman and Deal leadership frame theory condensed existing organizational theories into a four-frame perspective consisting of a structural, human resource, political, and symbolic frame. Bolman and Deal theorized that the ability to use more than one frame is considered to be critical to the success of leaders and intensify that leader's capacity for making decisions and taking effective actions. The Leadership Orientation Questionnaire (Self) contains five sections that include rating scales for personal demographics, the four frames, eight leadership dimensions, and management and leadership effectiveness. The research questions sought to identify the demographic characteristics and academic histories of the survey participants and the associations between these variables, the leadership frames represented among the survey participants, and how many, and which, of the four frames the survey participants use collectively. This study allowed its participants to examine their perceptions of their own leadership frames in order to analyze the frame that dominates the way certain universities communicate. Thirteen of the thirty presidents (43%) completed and returned the survey. Survey participants who had 20 or more years of experience were more likely to exhibit the human resource or symbolic frame as their dominant style; presidents whose years of experience numbered less than 20 years exhibited a mulitframe perspective in their decision-making process. Overall, this research found that the survey participants exhibited most often the human resource frame, followed by the symbolic, structural, and political frames.
- Ability Estimation Under Different Item Parameterization and Scoring Models
- A Monte Carlo simulation study investigated the effect of scoring format, item parameterization, threshold configuration, and prior ability distribution on the accuracy of ability estimation given various IRT models. Item response data on 30 items from 1,000 examinees was simulated using known item parameters and ability estimates. The item response data sets were submitted to seven dichotomous or polytomous IRT models with different item parameterization to estimate examinee ability. The accuracy of the ability estimation for a given IRT model was assessed by the recovery rate and the root mean square errors. The results indicated that polytomous models produced more accurate ability estimates than the dichotomous models, under all combinations of research conditions, as indicated by higher recovery rates and lower root mean square errors. For the item parameterization models, the one-parameter model out-performed the two-parameter and three-parameter models under all research conditions. Among the polytomous models, the partial credit model had more accurate ability estimation than the other three polytomous models. The nominal categories model performed better than the general partial credit model and the multiple-choice model with the multiple-choice model the least accurate. The results further indicated that certain prior ability distributions had an effect on the accuracy of ability estimation; however, no clear order of accuracy among the four prior distribution groups was identified due to an interaction between prior ability distribution and threshold configuration. The recovery rate was lower when the test items had categories with unequal threshold distances, were close at one end of the ability/difficulty continuum, and were administered to a sample of examinees whose population ability distribution was skewed to the same end of the ability continuum.
- The Relationship Among Gender, Gender Role Attitudes, and the Anticipated Commitment to Career, Marriage, Family, and Housework
- The relationships between gender, gender role attitudes, and participants' anticipation of future life roles (career, marriage, family, and homecare) were examined. Participants consisted of 297 single college students between the ages of 17-29 years (M = 20). Females reported significantly (p< .01) more egalitarian gender role attitudes than males. Significant results were found for the relationship between gender and anticipated life roles (p< .01) as well as between gender role attitudes and anticipated life roles (career role value, r = .14 and marital role value, r = - .18). The study findings suggest a possible gender conflict for females with more egalitarian gender role attitudes and behavior intentions and their male counterparts.
- Managerial self-awareness and its impact on leadership in high-performing managers.
- Managerial self-awareness is thought to impact leadership. A multi-rater feedback instrument was used to gather performance data on 70 managers in a large multi-national airline in regards to five leadership dimensions: making sound decisions, driving for results, effective communication, self-management, and innovation. Difference scores between self and direct reports were calculated and used as the operational definition of managerial self-awareness. T-tests were run to examine the difference between high performers and average performers. No significant differences were found. Additionally, correlational measures between the five leadership competencies and the managerial self-awareness measure indicated statistically weak relationships.
- Filial Therapy with Immigrant Korean Parents in the United States
- This study was designed to determine the effectiveness of filial therapy training in: (a) increasing immigrant Korean parents' empathic behavior with their children; (b) increasing immigrant Korean parents' acceptance level toward their children; and (c) reducing immigrant Korean parents' stress related to parenting.The experimental group, consisting of 17 immigrant Korean parents in the United States, received 10 weekly 2-hour filial therapy training sessions and participated in weekly 30-minute play sessions with one of their children. The control group, consisting of 15 immigrant Korean parents in the United States, received no treatment during the ten weeks. All the parents were videotaped playing with their child before and after the training as a means of measuring change in empathic behavior. The two written self-report instruments completed for pretesting and posttesting purposes were the Porter Parental Acceptance Scale and the Parenting Stress Index. Analyses of covariance revealed that the immigrant Korean parents in the experimental group had significant changes in 10 of 12 hypotheses, including (a) a significant increase in their level of empathic interactions with their children; (b) a significant increase in their attitude of acceptance toward their children; and (c) a significant reduction in their level of stress related to parenting. This study supports the use of filial therapy for promoting the parent-child relationship in immigrant Korean families in the United States. Filial therapy helps immigrant Korean parents to be therapeutic agents for their children. It helps them regain their own power as parents and restore positive relationships with their children.
- Hydrogen terminated silicon surfaces: Development of sensors to detect metallic contaminants and stability studies under different environments
- Hydrogen terminated silicon surfaces have been utilized to develop sensors for semiconductor and environmental applications. The interaction of these surfaces with different environments has also been studied in detail. The sensor assembly relevant to the semiconductor industry utilizes a silicon-based sensor to detect trace levels of metallic contaminants in hydrofluoric acid. The sensor performance with respect to two non-contaminating reference electrode systems was evaluated. In the first case, conductive diamond was used as a reference electrode. In the second case, a dual silicon electrode system was used with one of the silicon-based electrodes protected with an anion permeable membrane behaving as the quasi reference electrode. Though both systems could function well as a suitable reference system, the dual silicon electrode design showed greater compatibility for the on-line detection of metallic impurities in HF etching baths. The silicon-based sensor assembly was able to detect parts- per-trillion to parts-per-billion levels of metal ion impurities in HF. The sensor assembly developed for the environmental application makes use of a novel method for the detection of Ni2+using attenuated total reflection (ATR) technique. The nickel infrared sensor was prepared on a silicon ATR crystal uniformly coated by a 1.5 micron Nafion film embedded with dimethylglyoxime (DMG) probe molecules. The detection of Ni2+ was based on the appearance of a unique infrared absorption peak at 1572 cm-1 that corresponds to the C=N stretching mode in the nickel dimethylglyoximate, Ni(DMG)2, complex. The suitable operational pH range for the nickel infrared sensor is between 6-8. The detection limit of the nickel infrared sensor is 1 ppm in the sample solution of pH=8. ATR - FTIR spectroscopy was used to study the changes that the hydride mode underwent when subjected to different environments. The presence of trace amounts of Cu2+ in HF solutions was found to roughen the silicon surface as observed ATR-IR spectroscopy. The initial stages of oxidation in UPW and Cu2+ / UPW was studied. Trace amounts of Cu2+ were found to drastically increase the rate of oxidation, while the rate of oxidation was found to be retarded on removing dissolved oxygen that was present in UPW.
- Layered Double Hydroxides: Morphology, Interlayer Anion, and the Origins of Life
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The preparation of layered double hydroxides via co-precipitation of a divalent/trivalent metal solution against a base results in 1 mm LDH particles with a disorganized metal lattice. Research was performed to address these morphological issues using techniques such as Ostwald ripening and precipitation via aluminate. Another interesting issue in layered double hydroxide materials is the uptake and orientation of anions into the interlayer. Questions about iron cyanide interlayer anions have been posed. Fourier transform infared spectroscopy and powder x-ray diffraction have been used to investigate these topics. It was found that factors such as orientation, anion charge, and anion structure depended on the divalent/trivalent metal ratio of the hydroxide layer and reactivity time. The cyanide self-addition reaction is an important reaction of classical prebiotic chemistry. This reaction has been shown to give rise to amino acids, purines and pyrimidines. At cyanide concentrations similar to that expected on the early earth, hydrolysis to formamide rather than self-addition occurs. One theory to alleviate this side reaction is the use of minerals or clays that are thought to concentrate and catalyze prebiotics of interest. Layered double hydroxides have been studied as a catalyst for this reaction.
- Comparing Five Empirical Biodata Scoring Methods for Personnel Selection
- A biodata based personnel selection measure was created to improve the retention rate of Catalog Telemarketing Representatives at a major U.S. retail company. Five separate empirical biodata scoring methods were compared to examine their usefulness in predicting retention and reducing adverse impact. The Mean Standardized Criterion Method, the Option Criterion Correlation Method, Horizontal Percentage Method, Vertical Percentage Method, and Weighted Application Blank Method using England's (1971) Assigned Weights were employed. The study showed that when using generalizable biodata items, all methods, except the Weighted Application Blank Method, were similar in their ability to discriminate between low and high retention employees and produced similar low adverse impact effects. The Weighted Application Blank Method did not discriminate between the low and high retention employees.
- Working Whiteness: Performing And Transgressing Cultural Identity Through Work
- Early in Richard Wright's Native Son, we see Bigger and his friend Gus “playing white.” Taking on the role of “J. P. Morgan,” the two young black men give orders and act powerful, thus performing their perceived role of whiteness. This scene is more than an ironic comment on the characters' distance from the lifestyle of the J. P. Morgans of the world; their acts of whiteness are a representation of how whiteness is constructed. Such an analysis is similar to my own focus in this dissertation. I argue that whiteness is a culturally constructed identity and that work serves as a performative space for defining and transgressing whiteness. To this end, I examine work and its influence on the performance of middle class and working class whiteness, as well as how those outside the definitions of whiteness attempt to “play white,” as Bigger does. Work enables me to explore the codes of whiteness and how they are performed, understood, and transgressed by providing a locus of cultural performance. Furthermore, by looking at novels written in the early twentieth century, I am able to analyze characters at a historical moment in which work was of great import. With the labor movement at its peak, these novels, particularly those which specifically address socialism, participate in an understanding of work as a performative act more than a means to end. Within the context of this history and using the language of whiteness studies, I look at how gendered whiteness is transgressed and reinforced through the inverted job-roles of the Knapps in Dorothy Canfield's The Home-Maker, how work can cause those who possess the physical attributes of whiteness to transgress this cultural identity, as the Joads in The Grapes of Wrath demonstrate, and how the ascribed identities as non-white for Sara in The Bread Givers, Jurgis in The Jungle, and Bigger in Native Son are by far more compelling than their performative acts.
- Developmental Stressors and Associated Coping Skills in the Development of Disordered Eating in College Females
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There is a lack of clarity in the current literature in how potential etiological factors interact and result in disordered eating. The purpose of this study was to examine an expanded model of Personality, Social Support, Appraisal/Coping Processes, Abuse History, Internalization of Sociocultural Standards, Psychological Disturbances, and Body Disparagement in the development of disordered eating. The current model was evaluated using 276 women in their transition to college, a time period highly associated with symptoms believed to increase a woman's risk for the development of disordered eating including perceived difficulty coping, weight gain, and negative affect. Structural equation modeling was used to allow simultaneous examination of the causal relationships between the factors. Structural analyses confirmed that college women with previous stressful experiences appraised the adjustment to college as more stressful and reported feeling less able to cope with the transition. Those women who identified the transition as overwhelming were also aware of increased negative mood and psychological states since beginning the school semester. Further, women with previous traumatic sexual experiences appeared to be at additional risk for increased negative affective symptoms. The resulting model confirmed that those women who experience negative mood states and those that endorse strong internalization of cultural values regarding attractiveness encountered increased dissatisfaction and disapproval of their bodies. Finally, women with higher levels of body concern engaged in more eating behaviors associated with disordered eating. The roles of personality functioning and perceived social support could not be identified in the developmental model. The predictive links between constructs in the resulting model provide meaningful information regarding the transition to college and associated risks for development of disordered eating. Validation of the model in an independent sample would provide confirmation of these relationships and longitudinal research examining females' attitudes across crucial developmental periods might provide important information regarding which individuals are most at risk for development of disordered eating.
- Water Quality Aspects of an Intermittent Stream and Backwaters in an Urban North Texas Watershed
- Pecan Creek flows southeast through the City of Denton, Texas. Characterized as an urban watershed, the basin covers approximately 63.5 km2. Pecan Creek is an intermittent stream that receives nonpoint runoff from urban landuses, and the City of Denton's wastewater treatment plant, Pecan Creek Water Reclamation Plant, discharges effluent to the stream. Downstream from the City of Denton and the wastewater treatment plant, Pecan Creek flows about 6,000 m through agricultural, pasture, and forested landscapes into Copas Cove of Lake Lewisville, creating backwater conditions. Pecan Creek water quality and chemistry were monitored from August 1997 to October 2001. Water quality was influenced by seasonal, spatial, climatic, and diurnal dynamics. Wastewater effluent discharged from the Pecan Creek Water Reclamation Plant had the greatest influence on water quality of the stream and backwaters. Water quality monitoring of Pecan Creek demonstrated that dissolved oxygen standards for the protection of aquatic life were being achieved. Water quality modeling of Pecan Creek was completed to assess future increases in effluent flow from the Pecan Creek Water Reclamation Plant. Water quality modeling indicated that dissolved oxygen standards would not be achieved at the future effluent flow of 21 MGD and at NPDES permitted loadings. Model results with application of a safety factor indicated that the maximum allowable concentrations for a 21 MGD discharge would be 2.3 mg/L of ammonia and 7.0 mg/L of biochemical oxygen demand at summer conditions. Drought conditions that occurred from 1998 to 2001 reduced water levels in Lake Lewisville and impacted dissolved oxygen water quality in Pecan Creek. Water quality observations made during the period of drought allowed for the development of a model to estimate the zone of the dissolved oxygen sag in Pecan Creek based on reservoir elevation. Finally, monitoring results were analyzed with nonparametric statistical procedures to detect water quality changes in the backwater area of Pecan Creek, as influenced by storm events.
- Civil Asset Forfeiture in the Fight Against Drugs (Policy Analysis)
- Even if the main criminals of an organization are incarcerated, they will be replaced by others who would continue illegal activities, unless their financial assets are removed. Thus, civil forfeiture intends to dismantle the economic infrastructure of drug trafficking networks. Civil forfeiture considers the property as guilty, rather than the owner, and it may exist even if there is not a criminal action. Therefore, it is claimed that police agencies have chosen easy targets, such as wealthy drug users rather than major drug traffickers. Consequently, it has been particularly challenged on the basis of the Excessive Fines, Double Jeopardy, and Due Process Clauses. The use of criminal forfeiture instead of civil forfeiture and the elimination of the equitable sharing provision are considered to be the primary solutions.