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Acculturation and Sociocultural Influences as Predictors of Family Relationships and Body Image Dissatisfaction in African American, Hispanic American, and European American Women

Description: Ethnic differences in etiological factors linked to body image dissatisfaction and eating disorders were examined. In addition, the interaction of acculturation and body image dissatisfaction in influencing minority women's relationships with their parents was investigated. Participants consisted of 302 undergraduates from three ethnic groups: Caucasian, Hispanic American, and African American women who were administered self-report measures. Differences were not found between the groups in body image dissatisfaction. Low self-esteem, internalization of the thin ideal, and family emphasis on weight and appearance were all related to more body image dissatisfaction for each of these groups; however, differences in degree of endorsement were also noted between the ethnic groups on these factors. Based on the interaction findings (body image x acculturation) separation from one's mother was found in the area of attitudes and emotions for the Hispanic sample but not for the African American sample on any of the parent scales. Areas for future research and implications for diagnosis and treatment of minority populations are also discussed.
Date: December 2006
Creator: Garcia-Rea, Elizabeth Ann

Accuracy Variations in Human Facial Identification Based on Time of Exposure.

Description: This study examined the relationship between time of exposure to the human face and accurate subsequent photo line-up identification. A volunteer group of 124 undergraduate students was divided into three approximately equal sized subgroups. The three groups were then exposed to a video or a portion of a video depicting a theft. Exposure times ranged from two minutes to 30 seconds. The subjects were then given a questionnaire and shown a photo line-up of the mock perpetrator and five foils. Subjects were asked to identify the perpetrator and mark that identification on the questionnaire. Results of the experiment indicated that the longer a subject was exposed the greater the possibility of an accurate identification.
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Date: December 2006
Creator: Cowle, Kenneth M.

Adolescent Insomnia as a Predictor of Early Adulthood Outcomes

Description: Recent research found insomnia is a risk factor for psychiatric disorders in adults. To see if the same would be true in adolescents, the current study re-analyzed data from a national longitudinal study collected by ADDHealth that evaluated health behaviors in 4552 adolescents (mean age 14.9 years [SD 1.7]) at baseline and again 7-8 years later (n = 3489) during young adulthood. Insomnia was reported by 9.2% of the adolescents. Cross-sectionally, adolescent insomnia was associated with alcohol, cannabis, non-cannabis drugs, and tobacco use, and depression after controlling for gender and ethnicity. Prospectively, adolescent insomnia was a significant risk factor for depression diagnosis, suicidal ideation, and the use of depression and stress prescription medications in young adulthood after controlling for gender, ethnicity, and significant baseline variable. In addition, a trend was noted for suicidal attempts.
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Date: December 2006
Creator: Roane, Brandy Michelle

The American Doctrine for the Use of Naval Gunfire in Support of Amphibious Landings: Myth vs. Reality in the Central Pacific of World War II.

Description: The United States Marine Corps and the United States Navy developed during the interwar period a doctrine that addressed the problems inherent in the substitution of naval gunfire for artillery support in an amphibious assault. The invasion of Betio Islet, Tarawa Atoll, in November of 1943 was the first test of this doctrine. It has been said many times since the war that the doctrine basically passed this test and that lessons learned at Tarawa increased the efficiency with which the Marine Corps and Navy applied the prewar doctrine during the rest of the war. An analysis of the planning and execution of naval bombardments in the Central Pacific Campaign, after the invasion of the Gilberts, does not support this claim. This analysis leads the researcher to three conclusions. First, the Japanese developed defenses against many of the effects of the gunfire support doctrine that blunted much of the force of American firepower. American planners were slow to recognize the implications of these changes and, consequently, were slow to react to them. Second, many naval commanders responsible for providing naval gunfire support for Central Pacific operations still equated tonnage of ordnance to effectiveness of bombardment, regardless of their frequent references to "the lessons of Tarawa." Finally, strategic concerns and outright ignorance played a large part in determining the use of naval gunfire, the first taking precedence over the "lessons" and the second leading to the ignoring of the "lessons" all together.
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Date: December 2006
Creator: Mitchener, Donald Keith

Animals That Die

Description: The thesis has two parts. Part I is a critical essay entitled "Lessons Under the Amfalula." Part II is the collection of poems entitled "Animals That Die."
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Date: December 2006
Creator: Campbell, Susan Maxwell

An Approach Towards Self-Supervised Classification Using Cyc

Description: Due to the long duration required to perform manual knowledge entry by human knowledge engineers it is desirable to find methods to automatically acquire knowledge about the world by accessing online information. In this work I examine using the Cyc ontology to guide the creation of Naïve Bayes classifiers to provide knowledge about items described in Wikipedia articles. Given an initial set of Wikipedia articles the system uses the ontology to create positive and negative training sets for the classifiers in each category. The order in which classifiers are generated and used to test articles is also guided by the ontology. The research conducted shows that a system can be created that utilizes statistical text classification methods to extract information from an ad-hoc generated information source like Wikipedia for use in a formal semantic ontology like Cyc. Benefits and limitations of the system are discussed along with future work.
Date: December 2006
Creator: Coursey, Kino High

The Athlete Leader Role: Interaction of Gender, Sport Type, and Coaching Style.

Description: Effective leadership is a concept shown to be important for successful team performance in the fields of business, education, and sport. In sport, the role of the athlete leader has been under-examined and specifically, how coaching behaviors can affect athlete leader behaviors and how various leadership models (e.g., trait, behavioral, situational) relate to the athlete leader role has never been studied. The present study examined how autocratic, democratic, and collaborative coaching styles affect the athlete leader behavior preferences of athletes of different genders and sport types. Three coach scenarios reflecting the three aforementioned coaching styles were created so that athletes could imagine that they were coached by the individual presented in the scenario and then rate what type of athlete leader behaviors that they would prefer given the style of the coach that they read about. Results showed that the coach scenarios failed to have a significant impact; however, significant differences were discovered between men and women and between individual and team sport athletes on variables measuring preferred performance/task, relationship, motivation, and representation behaviors. Data were gathered on the style of athletes' current coach and this variable also produced significant differences for such behaviors as resolving conflict, providing positive reinforcement, and acting respectfully towards others. In addition, exploratory analyses showed that athletes who hold different leadership positions prefer different athlete leader behaviors. The current study seemed to offer concrete evidence on how coaching style can affect athlete leader preferences and how the athlete leader role can be explained by trait, behavioral, and situational leadership theories; however, future studies will have to further explore the impact that a coach's style can have on the behavior of athlete leaders as well as analyzing the relationship between athlete leaders and teammates utilizing the transformational leadership approach.
Date: December 2006
Creator: Wildman, Jonathan C. Jr.

Athletic Trainers and Psychological Disorders Among Athletes: An Examination of Their Abilities to Recognize, Diagnose and Intervene.

Description: Utilizing an analogue research design conducted via the Internet, this study assessed athletic trainers' abilities to recognize, diagnose, and intervene with a hypothetical athlete experiencing depression, and examined the impact of their gender, athlete gender, and athlete's presenting problem on their decisions. Athletic trainers' perceived competency in using psychosocial interventions with athletes, history of referring athletes to psychology professionals, and training backgrounds in psychology also were examined. Participants (270 male and 370 female certified athletic trainers) were randomly assigned to one of six conditions (Athlete Gender X Presenting Problem). After reading the appropriate vignette, they completed questions related to the athlete's psychological symptoms and diagnosis, referral recommendations, and use of psychosocial interventions if working with the athlete. The vignettes were identical except for the athlete's gender and problem. Overall, athletic trainers accurately identified the athlete's depressive symptoms/diagnosis and need for psychological referral. They rated the athlete significantly higher in Depressive Symptoms than in Anger/Agitation Symptoms and Compulsive Behavioral Symptoms, and as more likely to be experiencing a depressive disorder compared to an adjustment disorder, anxiety disorder, sleep disorder, or substance abuse disorder. Female athletic trainers provided significantly higher ratings of Depressive Symptoms than males and the injured athlete was rated significantly higher in Anger/Agitation than the performance problem athlete. Diagnosis ratings were not influenced by athlete gender, athletic trainer gender, or type of problem. Athletic trainers were most likely to refer the athlete to a psychology professional compared to an allied health professional, treating the athlete themselves, or doing nothing. Presenting problem significantly impacted referral recommendations. If treating the athlete themselves, athletic trainers were significantly more likely to use supportive interventions than cognitive-behavioral techniques; they felt significantly more competent in providing supportive interventions. Competency in both interventions was significantly enhanced if athletic trainers completed psychology coursework. Findings suggest that athletic ...
Date: December 2006
Creator: Albinson, Courtney Brooks

Attachment Processes, Stress Processes, and Sociocultural Standards in the Development of Eating Disturbances in College Women

Description: Minimal empirical research using longitudinal data to explore integrative models of eating disorder development exists. The purpose of this study was to further explore multidimensional models incorporating parental attachment, history of stress, appraisal/coping processes, internalization of the thin-ideal, negative affect, body image, and eating disordered behavior using prospective, longitudinal data. The models were evaluated using 238 participants who completed an initial series of self-report questionnaires during their first semester in college and completed follow-up questionnaires 6 months and 18 months later. Structural equation modeling was used to examine the relationships among the factors. Analyses confirmed that college freshman with insecure parental attachment relationships and those with a history of previous stressful experiences appraised the adjustment to college as more stressful and reported feeling less able to cope with the transition; these conditions predicted increased negative affect and increased eating disturbances. Women who reported experiencing negative affect and those that endorsed internalization of the thin-ideal also reported higher levels of body dissatisfaction; these women engaged in more disordered eating attitudes and behaviors. A second model investigating negative affect as mediating the relationship between the appraisal/coping process and eating disturbances also revealed that experiencing difficulties with the transition to college predicted later negative mood states. Further, women who reported increased negative affect also reported increased eating disturbances. Finally, cross-lagged and simultaneous effects between selected factors were evaluated. Results from these analyses are mixed, but they provide additional information about the predictive relationships among factors that play a role in the development of eating disorders. The results of this study provide valuable information about the development of eating disorders that can be used to aid prevention and treatment. Examination of these models in a large independent sample might provide confirmation of these relationships, and investigation of the models during different developmental periods might ...
Date: December 2006
Creator: Bradford, Jennifer Wolf

Attachment Styles in a Sample from a Correctional Drug Treatment Facility

Description: Substance abuse and dependence causes many problems in our society. Attachment style may be useful in the etiology of this problem. Using archival data, this study hypothesizes men in a court-ordered facility will be more likely to have an insecure attachment style. The participants were 73 males ages 18-49. The Adult Attachment Scale (AAS) was used to measure adult romantic attachment style. Through cluster analysis and conversion of the subscales of the AAS, four attachment styles were measured. Men were more likely to have an insecure attachment style especially a Fearful style. The study concludes with limitations of the results and a discussion about possible interventions based on attachment style.
Date: December 2006
Creator: Shivpuri, Michelle Yvonne

Bank Loans as a Financial Discipline: A Direct Agency Cost of Equity Perspective

Description: In a 2004 study, Harvey, Lin and Roper argue that debt makers with a commitment to monitoring can create value for outside shareholders whenever information asymmetry and agency costs are pronounced. I investigate Harvey, Lin and Roper's claim for bank loans by empirically testing the effect of information asymmetry and direct agency costs on the abnormal returns of the borrowers' stock around the announcement of bank loans. I divide my study into two main sections. The first section tests whether three proxies of the direct agency costs of equity are equally significant in measuring the direct costs associated with outside equity agency problems. I find that the asset utilization ratio proxy is the most statistically significant proxy of the direct agency costs of equity using a Chow F-test statistic. The second main section of my dissertation includes and event study and a cross-sectional analysis. The event study results document significant and positive average abnormal returns of 1.01% for the borrowers' stock on the announcement day of bank loans. In the cross sectional analysis of the borrowers' average abnormal stock returns, I find that higher quality and more reputable banks/lenders provide a reliable certification to the capital market about the low level of the borrowers' direct agency costs of equity and information asymmetry. This certification hypothesis holds only for renewed bank loans. In other words, in renewing the borrowers' line of credit, the bank/lender is actually confirming that the borrower has a low level of information asymmetry and direct costs of equity. Given such a certificate from the banks/lenders, shareholders reward the company/borrower by bidding the share price up in the capital market.
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Date: December 2006
Creator: Hijazi, Bassem

The "Beethoven Folksong Project" in the Reception of Beethoven and His Music

Description: Beethoven's folksong arrangements and variations have been coldly received in recent scholarship. Their melodic and harmonic simplicity, fusion of highbrow and lowbrow styles, seemingly diminished emphasis on originality, and the assorted nationalities of the tunes have caused them to be viewed as musical rubble within the heritage of Western art music. The canonic composer's relationship with the Scottish amateur folksong collector and publisher George Thomson, as well as with his audience, amateur music lovers, has been largely downplayed in the reception of Beethoven. I define Beethoven's engagement with folksongs and their audience as the "Beethoven Folksong Project," evaluating it in the history of Beethoven reception as well as within the cultural and ideological contexts of the British Isles and German-speaking lands at the turn of the nineteenth century. I broaden the image of Beethoven during his lifetime by demonstrating that he served as an ideal not only for highly educated listeners and performers but also for amateur music lovers in search of cultivation through music. I explore the repertory under consideration in relation to the idea of Bildung ("formation" or "education" of the self or of selves as a nation) that pervaded contemporary culture, manifesting itself in music as the tradition of Bildungsmusik ("music for self-improvement"). Drawing on both contemporary reviews and recent studies, I show that the music's demanding yet comprehensible nature involved a wide range of elements from folk, popular, and chamber music to Hausmusik ("house music"), Unterhaltungsmusik ("music for entertainment"), Alpenmusik ("music of the Alps"), and even Gassenhauer ("street music"). Within the tradition of Bildungsmusik, adaptation of folksongs for domestic music-making, recomposition of pre-existing materials, collaboration between professionals and amateurs, and incorporation of musics familiar to and popular with contemporaries served as significant means for the composer to communicate with a middle-class audience. The hybrid and flexible ...
Date: December 2006
Creator: Lee, Hee Seung

Beethoven's Opus 18 String Quartets: Selected First Movements in Consideration of the Formal Theories of Heinrich Koch as Expressed in Versuch Einer Anleitung Zur Composition

Description: Heinrich Koch completed his treatise in 1793, a pioneering work regarding the musical phrase as well as a sonata form description (lacking that term). Composition of Opus 18 began in 1798, a momentous project for several reasons in Beethoven's early career. Here, the theories expressed in Koch's Versuch are taken as an analytic springboard into a thorough analysis of the first movement of the quartet published no. 3, which was the first composed; additionally, nos. 1 and 6 are explored to a lesser degree. This study in phrase-analysis demonstrates significance in the fundamental ideas of Koch as applied to a masterwork of the turn of the 19th century.
Date: December 2006
Creator: Tompkins, Robert

Between the Waves: Truth-Telling, Feminism, and Silence in the Modernist Era Poetics of Laura Riding Jackson and Muriel Rukeyser

Description: This paper presents the lives and early feminist works of two modernist era poets, Laura Riding Jackson and Muriel Rukeyser. Despite differences of style, the two poets shared a common theme of essentialist feminism before its popularization by 1950s and 60s second wave feminists. The two poets also endured periods of poetic silence or self censorship which can be attributed to modernism, McCarthyism, and rising conservatism. Analysis of their poems helps to remedy their exclusion from the common canon.
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Date: December 2006
Creator: Cain, Christina

Characterization, Properties and Applications of Novel Nanostructured Hydrogels.

Description: The characterization, properties and applications of the novel nanostructured microgel (nanoparticle network and microgel crystal) composed of poly-N-isopropylacrylanmide-co-allylamine (PNIPAM-co-allylamine) and PNIPAM-co-acrylic acid(AA) have been investigated. For the novel nanostructured hydrogels with the two levels of structure: the primary network inside each individual particle and the secondary network of the crosslinked nanoparticles, the new shear modulus, drug release law from hydrogel with heterogeneous structure have been studied. The successful method for calculating the volume fraction related the phase transition of colloid have been obtained. The kinetics of crystallization in an aqueous dispersion of PNIPAM particles has been explored using UV-visible transmission spectroscopy. This dissertation also includes the initial research on the melting behavior of colloidal crystals composed of PNIPAM microgels. Many new findings in this study area have never been reported before. The theoretical model for the columnar crystal growth from the top to bottom of PNIPAM microgel has been built, which explains the growth mechanism of the novel columnar hydrogel colloidal crystals. Since the unique structure of the novel nanostructured hydrogels, their properties are different with the conventional hydrogels and the hard-sphere-like system. The studies and results in this dissertation have the important significant for theoretical study and valuable application of these novel nanostructured hydrogels.
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Date: December 2006
Creator: Tang, Shijun

Chen Yi and Her Choral Music: A Study of the Composer's Ideal of Fusing Chinese Music and Modern Western Choral Traditions

Description: Chen Yi's music is well accepted and recognized nationally and internationally through an increasing number of commissions and performances. Major symphony orchestras, choruses, institutions and companies request her compositions on many occasions in order to increase understanding and exploration of Chinese influences on western classical idioms. This study provides the first detailed discussion of her compositional mastery and her fusion of Chinese music with the language of western choral traditions. Chen Yi's reputation as a prominent orchestral composer does not restrain her passion to apply instrumental techniques and materials to her quality choral compositions. This study focuses on (1) how hardship and various life experiences during the ten-year Cultural Revolution shaped Chen Yi's musical inspirations; (2) how the influences of major musical genres, such as traditional Chinese folksong, jingju, model play, 19th-20th century nationalism, impressionism, and serialism are consolidated in her kaleidoscopic compositional techniques; and (3) the application of Chinese languages, pedagogical concepts, and extra-musical elements, such as Chinese poems, paintings, and calligraphies, revealed in her original, intelligent and resourceful choral creations.
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Date: December 2006
Creator: Yeung, Hin-Kei

CLUE: A Cluster Evaluation Tool

Description: Modern high performance computing is dependent on parallel processing systems. Most current benchmarks reveal only the high level computational throughput metrics, which may be sufficient for single processor systems, but can lead to a misrepresentation of true system capability for parallel systems. A new benchmark is therefore proposed. CLUE (Cluster Evaluator) uses a cellular automata algorithm to evaluate the scalability of parallel processing machines. The benchmark also uses algorithmic variations to evaluate individual system components' impact on the overall serial fraction and efficiency. CLUE is not a replacement for other performance-centric benchmarks, but rather shows the scalability of a system and provides metrics to reveal where one can improve overall performance. CLUE is a new benchmark which demonstrates a better comparison among different parallel systems than existing benchmarks and can diagnose where a particular parallel system can be optimized.
Date: December 2006
Creator: Parker, Brandon S.

Coelomic Fluid Protein Profile in Earthworms Following Bacterial Challenge.

Description: Proteomic techniques were used to evaluate the protein profile of the earthworm, (Lumbricus terrestris), following a bacterial challenge. One control group received no injection; a second control group received injections of phosphate buffer solution (PBS). The experimental group received injections of PBS containing (Aeromonas hydrophila). After incubation for 12 hours at 20°C, coelomic fluid was collected from each group for analysis by 2-D electrophoresis. There were significant differences in spot appearance and density between control and experimental groups. Sixteen spots showed a two-fold increase in density and 63 showed at least a two-fold decrease in density between samples from control and bacteria-challenged earthworms, respectively, suggesting up- and down-modulation of proteins potentially involved in the earthworm's response to bacterial challenge.
Date: December 2006
Creator: Brooks, Geoffrey Lance

Cognitive Complexity and Construct Extremity in Social and Life Event Construing in Persons with Varied Trauma History

Description: The purpose of this study was to examine cognitive complexity, extremity, and the relationship between social repertory grids and life events repertory grids (LERG) in people who report a history of trauma. Effects of type of trauma on complexity and extremity scores of each type of grid were examined. Prior research into repertory grids and trauma has used only one type of grid, predominantly social grids or LERGs. Therefore, a natural, progressive step in the grid research involved investigating how individuals integrate social and life event constructs. It was hypothesized, and results show, that there is a positive correlation between complexity scores and extremity scores of social grids and LERGs. However it was not found that there was a negative correlation between trauma history and complexity scores, and that trauma acts as a moderator for cognitive complexity. Instead, it appears that the social facet of experience is key to understanding perception of traumatic experiences. Additionally, number of traumas experienced might affect social construct elaboration.
Date: December 2006
Creator: Shafenberg, Stacey

Compact Operators and the Schrödinger Equation

Description: In this thesis I look at the theory of compact operators in a general Hilbert space, as well as the inverse of the Hamiltonian operator in the specific case of L2[a,b]. I show that this inverse is a compact, positive, and bounded linear operator. Also the eigenfunctions of this operator form a basis for the space of continuous functions as a subspace of L2[a,b]. A numerical method is proposed to solve for these eigenfunctions when the Hamiltonian is considered as an operator on Rn. The paper finishes with a discussion of examples of Schrödinger equations and the solutions.
Date: December 2006
Creator: Kazemi, Parimah

Comparative Study of RSS-Based Collaborative Localization Methods in Wireless Sensor Networks

Description: In this thesis two collaborative localization techniques are studied: multidimensional scaling (MDS) and maximum likelihood estimator (MLE). A synthesis of a new location estimation method through a serial integration of these two techniques, such that an estimate is first obtained using MDS and then MLE is employed to fine-tune the MDS solution, was the subject of this research using various simulation and experimental studies. In the simulations, important issues including the effects of sensor node density, reference node density and different deployment strategies of reference nodes were addressed. In the experimental study, the path loss model of indoor environments is developed by determining the environment-specific parameters from the experimental measurement data. Then, the empirical path loss model is employed in the analysis and simulation study of the performance of collaborative localization techniques.
Date: December 2006
Creator: Koneru, Avanthi

Comparison and Evaluation of Existing Analog Circuit Simulator using Sigma-Delta Modulator

Description: In the world of VLSI (very large scale integration) technology, there are many different types of circuit simulators that are used to design and predict the circuit behavior before actual fabrication of the circuit. In this thesis, I compared and evaluated existing circuit simulators by considering standard benchmark circuits. The circuit simulators which I evaluated and explored are Ngspice, Tclspice, Winspice (open source) and Spectre® (commercial). I also tested standard benchmarks using these circuit simulators and compared their outputs. The simulators are evaluated using design metrics in order to quantify their performance and identify efficient circuit simulators. In addition, I designed a sigma-delta modulator and its individual components using the analog behavioral language Verilog-A. Initially, I performed simulations of individual components of the sigma-delta modulator and later of the whole system. Finally, CMOS (complementary metal-oxide semiconductor) transistor-level circuits were designed for the differential amplifier, operational amplifier and comparator of the modulator.
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Date: December 2006
Creator: Ale, Anil Kumar

A Comparison of Written Composition Assessment Using Standard Format Versus Alternate Format Among College-Bound Students with Learning Disabilities and/or Attention-Deficit/Hyperactivity Disorder.

Description: The purpose of this study was to explore the efficacy of using a computer word processing program in the assessment of written expression with college-bound individuals who had been diagnosed with a learning disability (LD) and/or attention-deficit/hyperactivity disorder (ADHD). Fifty-six (35 eleventh and 21 twelfth) graders, attending a private college-preparatory school for students with LD and/or ADHD, were administered the Spontaneous Writing composite of the Test of Written Expression - Third Edition (TOWL-3). The TOWL-3 has equivalent forms, Form A and Form B. One form was administered in accordance with the test manual, using paper and pencil (standard format). The other form (i.e., alternate format) was administered with word processing access. Paired samples tests (repeated measure) and bivariate correlation designs were computed to explore the relationships between measures. Results of the study revealed significant increases (p<.01) in the subtest and composite scores when participants were administered the test in the alternate format. Other components of the research study did not reveal strong meaningful relationships when cognitive ability, graphomotor speed, and keyboarding rate were compared with the standard and/or alternative formats of the writing composite. A high rate of comorbity was exhibited with the majority of participants (75%) having two or more LD and/or ADHD diagnoses. On an informal questionnaire, the participants endorsed a strong preference for the use of word processors in the majority of their written academic tasks. The study concludes that for students who are accustomed to producing written work on a word processor, restriction from this writing tool can adversely affect the results of their product, leaving a false impression, underestimating their writing skills, ability, creativity, and subject knowledge. In addition, having access to a word processor during high stakes testing is paramount. Inaccurate results can affect future opportunities, such as admission to postsecondary educational settings. In ...
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Date: December 2006
Creator: Morris, Mary Ann

Computational Studies of Coordinatively Unsaturated Transition Metal Complexes

Description: In this research the validity of various computational techniques has been determined and applied the appropriate techniques to investigate and propose a good catalytic system for C-H bond activation and functionalization. Methane being least reactive and major component of natural gas, its activation and conversion to functionalized products is of great scientific and economic interest in pure and applied chemistry. Thus C-H activation followed by C-C/C-X functionalization became crux of the synthesis. DFT (density functional theory) methods are well suited to determine the thermodynamic as well as kinetic factors of a reaction. The obtained results are helpful to industrial catalysis and experimental chemistry with additional information: since C-X (X = halogens) bond cleavage is important in many metal catalyzed organic syntheses, the results obtained in this research helps in determining the selectivity (kinetic or thermodynamic) advantage. When C-P bond activation is considered, results from chapter 3 indicated that C-X activation barrier is lower than C-H activation barrier. The results obtained from DFT calculations not only gave a good support to the experimental results and verified the experimentally demonstrated Ni-atom transfer mechanism from Ni=E (E = CH2, NH, PH) activating complex to ethylene to form three-membered ring products but also validated the application of late transition metal complexes in respective process. Results obtained supported the argument that increase in metal coordination and electronic spin state increases catalytic activity of FeIII-imido complexes. These results not only encouraged the fact that DFT and multi-layer ONIOM methods are good to determine geometry and thermodynamics of meta-stable chemical complexes, but also gave a great support to spectroscopic calculations like NMR and Mossbauer calculations.
Date: December 2006
Creator: Vaddadi, Sridhar