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The Mercury-Sensitized Photochemical Reactions of Isopropyl Benzene and Methylcyclohexane
This thesis describes the theoretical results of mercury-sensitized photochemical reactions of isopropyl benzene and methylcyclohexane. The reactions are carried out and the results are analyzed. digital.library.unt.edu/ark:/67531/metadc97017/
Merging Departments, Service Desks and Staff: Managing Change While Improving Customer Service and Staff Morale
Presentation for the 2014 Oklahoma Library Association Annual Conference. This presentation discusses merging departments, service desks and staff and managing change while improving customer service and staff morale. digital.library.unt.edu/ark:/67531/metadc306980/
The message and ministry of Howard G. Hendricks in Christian higher education
Howard G. Hendricks influenced generations of leaders in Christian education during the last half of the 20th century through the practical communication of his unique message and the personal nature of his teaching ministry. This study explored his life through interpretive biography, compared his message with current models of secular and religious education, and evaluated his ministry through case study research. Hendricks has contributed to the field of Christian higher education through the publication of several books and periodical articles, as well as film series, audiotapes, and videotapes. He has presented thousands of messages across America and in over 75 countries worldwide. Hendricks has spent his entire 50-year educational career at Dallas Theological Seminary, teaching in the classroom, mentoring his students, and modeling positive values of Christian leadership. Chapter 1 introduces the study, explains the purpose and significance of the project, and defines key terms. Chapter 2 describes the methodology employed for the study. Chapter 3 provides an interpretive biography of Hendricks, and chapter 4 compares the educational philosophy of Hendricks with secular and Christian models. Chapter 5 examines the ministry of Hendricks in a case study approach. Chapter 6 summarizes the study and offers conclusions and implications for future research. digital.library.unt.edu/ark:/67531/metadc2791/
Message from United States Senator John Cornyn for the 2015 Open Access Symposium
Video message delivered by United States Senator John Cornyn for the 2015 UNT Open Access Symposium, hosted by the UNT Dallas College of Law. digital.library.unt.edu/ark:/67531/metadc505016/
The Messenger in Shakespeare
The messenger genus is a broad one. It contains several species and sub-species, some of which will hardly seem to belong to the group until they are examined from a functional or structural standpoint. An attempt will be made to break this great group into three species. digital.library.unt.edu/ark:/67531/metadc130421/
A Meta-analysis of Burnout and Occupational Stress
The relationship between occupational stress and burnout was investigated through a meta-analysis of 81 studies and 364 correlations. Occupational stress was measured by role conflict, role ambiguity, workload, cumulative role stress, job specific stress/stressors, and work setting characteristics. Burnout was measured by the Maslach Burnout Inventory, 1981 and 1986 versions, emotional exhaustion, depersonalization, and reduced personal accomplishment components of burnout, measures of tedium, and the Staff Burnout Scale for Health Professionals. Thirty occupations in human and non-human service organizations throughout four publication periods were examined. Results indicated occupational stress strongly predicts burnout in non-human service organizations like industry and manufacturing as well as the human services. Job specific stressors most strongly predict burnout across organization types and occupation. Occupational stress predicts emotional exhaustion and depersonalization more than perceptions of reduced personal accomplishment. The findings support the use of transactional models of stress which consider occupational context as a precipitator of burnout, especially emotional exhaustion. digital.library.unt.edu/ark:/67531/metadc278263/
Meta-Analysis of Meditation Outcomes in Counseling and Psychtherapy
Meditation includes a variety of techniques that share a common conscious effort to focus attention in a non-analytic way. In terms of its goals, meditation is a state of completely focused attention devoid of external thoughts--a state of heightened choice-less awareness. This study was designed to: (1) Identify and critically review professional literature on the effectiveness of meditation; (2) Provide an overall measure of effectiveness through the statistical meta-analysis technique; (3) Provide a classification of findings through the voting method; and (4) summarize and integrate highlights and major findings for the purpose of generating implications for future research and practice in counseling and psychotherapy. digital.library.unt.edu/ark:/67531/metadc278465/
Meta-Analysis of Reading Interventions for Students with Learning and Emotional Disabilities
Developing effective literacy skill has become an increasingly critical skill in today's information age. Students with emotional/behavioral disorders (E/BD) routinely lack these skills and are not being taught how to read effectively. The field of special education needs more comprehensive and specific information about how to most effectively teach reading skills to students with E/BD. When reading interventions are conducted using student with E/BD, the interventions are generally drawn from the LD field. The assumption is that the reading interventions that have worked with students with LD will work equally well with the E/BD population. This study performed a meta-analysis to examine whether reading interventions are equally effective on the E/BD and LD populations. In addition, it will examine whether the instruction mode (e. g., peer, self, or teacher directed), gender, or grade group affects the success of the intervention. The meta-analysis found that the reading interventions for both disability groups had high effect sizes. In addition, neither disability group, teaching method, gender, nor grades were predictive of the variance in the effect size. These results indicate that reading programs that have been designed for students with LD are also effective for students with E/BD and furthermore, reading programs can improve the academic achievement of students with behavioral disorders. Recommendations for teacher training and future research are given based on these results. digital.library.unt.edu/ark:/67531/metadc4866/
A meta-analysis of service learning research in middle and high schools.
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This study examines the relationship between service learning innovations and improved academics, self-concept, and social or personal growth in middle and high school students. Meta-Analysis is employed to arrive at effect-size estimates for each construct. A historical overview of service learning is presented and a detailed description of the study selection process is provided. The data revealed a moderate relationship between service learning participation and academics, self-concept and social or personal growth in middle and high school students. The findings are presented, and some appropriate conclusions are drawn. A discussion of the implications of these findings and recommendations for future research are also provided. digital.library.unt.edu/ark:/67531/metadc2995/
Meta-Analysis of the Impact of After-School Programs on Students Reading and Mathematics Performance
The purpose of this study employing meta-analysis was to assess the impact that after-school programs have on reading and mathematics outcomes. The participants in the primary studies were students in Grades K through 8; years 200 through 2009. The study utilized the theory of change as its theoretical basis. This meta-analysis used the effect size as the standard measure. It began with an overall Cohen's d of .40 for the impact that after-school programs have on reading and mathematics outcomes, and then proceeded to analyze three moderator variables: subject, time periods, and grade level.The findings of the meta-analysis, both overall and sub analyses, show that the independent variable, after-school programs, has an impact on the dependent variable, reading and mathematics. The overall results indicated that after-school programs are educationally significant in the areas of reading and mathematics combined. As for the moderator variable, the results for the areas of (a) subject (reading and mathematics), (b) time period (2000-2002, 2003-2005 and 2006-2009), and (c) grade (middle, and middle plus elementary combined), all indicated educationally significant results. The notable exception was the grade moderator, elementary.This study provides more information for researchers, practitioners and policy makers upon which to make practical research based decisions about after-school programs for the purpose of determining the applicability of such in their educational setting. digital.library.unt.edu/ark:/67531/metadc67972/
Meta-Parenting in Parents of Infants and Toddlers
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Meta-parenting, defined as parents thinking about their parenting, has been identified and is a new field of research. The purposes of this study were to add to the existing knowledge of meta-parenting and to compare the influences of gender, work status, and parenting experience on meta-parenting occurring in parents of infants and toddlers. Sixty parents participated either electronically or by completing a written survey and reported engaging from "sometimes" to "usually" in four domains of meta-parenting: anticipating, assessing, reflecting, and problem-solving. Gender, work status, and parenting experience did not significantly influence participants' meta-parenting scores. Parents were found to have a higher sense of satisfaction and overall sense of competence when they engaged in higher levels of meta-parenting. digital.library.unt.edu/ark:/67531/metadc5566/
MetaArchive: Final Report
This report provides summary information about the goals, activities, and results of this project, focusing on January 2008-December 2011. Section One will provide a brief summary of the outcomes of the project work based on the authors' project's performance objectives. Section Two will offer a brief reiteration of the authors' project's original goals and ambitions and an in-depth discussion of the authors' findings and development activities. Section Three will describe plans for the program's continuation and its long-term impact. Section Four will provide a list of the staff who have worked on various aspects of this project during the project period. digital.library.unt.edu/ark:/67531/metadc109710/
Metabolic, cardiac and ventilatory regulation in early larvae of the South African clawed frog, Xenopus laevis.
Early development of O2 chemoreception and hypoxic responses under normoxic (150 mmHg) and chronically hypoxic (110 mmHg) conditions were investigated in Xenopus laevis from hatching to 3 weeks post fertilization. Development, growth, O2 consumption, ventilatory and cardiac performance, and branchial neuroepithelial cells (NEC) density and size were determined. At 3 days post fertilization (dpf), larvae started gill ventilation at a rate of 28 ± 4 beats/min and showed increased frequency to 60 ± 2 beats/min at a PO2 of 30 mmHg. Also at 3 dpf, NECs were identified in the gill filament buds using immunohistochemical methods. Lung ventilation began at 5 dpf and exhibited a 3-fold increase in frequency from normoxia to a PO2 of 30 mmHg. Hypoxic tachycardia developed at 5 dpf, causing an increase of 20 beats/min in heart rate, which led to a 2-fold increase in mass-specific cardiac output at a PO2 of 70 mmHg. At 10 dpf, gill ventilatory sensitivity to hypoxia increased, which was associated with the increase in NEC density, from 15 ± 1 to 29 ± 2 cells/mm of filament at 5 and 10 dpf, respectively. Unlike the elevated rate, cardiac and ventilatory volumes were independent of acute hypoxia. Despite increased cardioventilatory frequency, larvae experienced an average of 80% depression in during acute hypoxia. Chronic hypoxia (PO2 of 110 mmHg) decreased mass-specific cardiac performance before 10 dpf. In older larvae (10 to 21 dpf), chronic hypoxia decreased acute branchial and pulmonary hypoxic hyperventilation and increased NEC size. Collectively, these data suggest that larvae exhibit strong O2-driven acute hypoxic responses post-hatching, yet are still O2 conformers. All acute hypoxic responses developed before 5 dpf, and then the effects of chronic hypoxia started to show between 7 and 21 dpf. Thus, the early formation of acute hypoxic responses is susceptible to the environment and can be shaped by the ambient PO2. digital.library.unt.edu/ark:/67531/metadc12175/
Metabolic Engineering in Plants to Control Source/sink Relationship and Biomass Distribution
Traditional methods like pruning and breeding have historically been used in crop production to divert photoassimilates to harvested organs, but molecular biotechnology is now poised to significantly increase yield by manipulating resource partitioning. It was hypothesized that metabolic engineering in targeted sink tissues can favor resource partitioning to increase harvest. Raffinose Family Oligosaccharides (RFOs) are naturally occurring oligosaccharides that are widespread in plants and are responsible for carbon transport, storage and protection against cold and drought stress. Transgenic plants (GRS47, GRS63) were engineered to generate and transport more RFOs through the phloem than the wild type plants. The transgenic lines produced more RFOs and the RFOs were also detected in their phloem exudates. But the 14CO2 labeling and subsequent thin layer chromatography analysis showed that the RFOs were most likely sequestered in an inactive pool and accumulate over time. Crossing GRS47 and GRS63 lines with MIPS1 plants (that produces more myo-inositol, a substrate in the RFO biosynthetic pathway) did not significantly increase the RFOs in the crossed lines. For future manipulation of RFO degradation in sink organs, the roles of the endogenous α-galactosidases were analyzed. The alkaline α-galactosidases (AtSIP1 and AtSIP2 in Arabidopsis) are most likely responsible for digesting RFOs in the cytoplasm and may influence the ability to manipulate RFO levels in engineered plants. Atsip1/2 (AtSIP1/AtSIP2 double-knockout plants) were generated and phenotypically characterized based on seed germination patterns, flowering time, and sugar content to observe the impact on RFO sugar levels. The observations and analysis from these lines provide a basis for further insight in the manipulation of resource allocation between source and sink tissues in plants for future research. digital.library.unt.edu/ark:/67531/metadc283836/
Metabolic Engineering of Raffinose-Family Oligosaccharides in the Phloem Reveals Alterations in Patterns of Carbon Partitioning and Enhances Resistance to Green Peach Aphid
Phloem transport is along hydrostatic pressure gradients generated by differences in solute concentration between source and sink tissues. Numerous species accumulate raffinose-family oligosaccharides (RFOs) in the phloem of mature leaves to accentuate the pressure gradient between source and sinks. In this study, metabolic engineering was used to generate RFOs at the inception of the translocation stream of Arabidopsis thaliana, which transports predominantly sucrose. To do this, three genes, GALACTINOL SYNTHASE, RAFFINOSE SYNTHASE and STACHYOSE SYNTHASE, were expressed from promoters specific to the companion cells of minor veins. Two transgenic lines homozygous for all three genes (GRS63 and GRS47) were selected for further analysis. Sugars were extracted and quantified by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), and 21-day old plants of both lines had levels of galactinol, raffinose, and stachyose approaching 50% of total soluble sugar. All three exotic sugars were also identified in phloem exudates from excised leaves of transgenic plants whereas levels were negligible in exudates from wild type leaves. Differences in starch accumulation or degradation between wild type and GRS63 and GRS47 lines were not observed. Similarly, there were no differences in vegetative growth between wild type and engineered plants, but engineered plants flowered earlier. Finally, since the sugar composition of the phloem translocation stream is altered in these plants, we tested for aphid feeding. When green peach aphids were given a choice between WT and transgenic plants, WT plants were preferred. When aphids were reared on only WT or only transgenic plants, aphid fecundity was reduced on the transgenic plants. When aphids were fed on artificial media with and without RFOs, aphid reproduction did not show differences, suggesting the aphid resistance is not a direct effect of the exotic sugars. digital.library.unt.edu/ark:/67531/metadc30441/
Metabolic Syndrome and Psychosocial Factors
Metabolic syndrome is a constellation of risk factors, including abdominal obesity, hypertriglyceridemia, low HDL cholesterol, high blood pressure, and high fasting glucose, that commonly cluster together and can result in cardiovascular disease. The prevalence of metabolic syndrome and the components that comprise the syndrome vary by age and by racial/ethnic group. In addition, previous research has indicated that the risk factors contributing to metabolic syndrome may be exacerbated by exposure to perceived stress. This study utilized data from the 2002, 2004, and 2006 Health and Retirement Study (HRS) and National Health and Nutrition Examination Survey (NHANES) data sets. It was hypothesized that depression and anxiety (conceptualized as stress in this study) increase the risk of presenting with metabolic syndrome while social support decreases the risk of metabolic syndrome. While results of cross-sectional analysis do not indicate a significant relationship between depression and metabolic syndrome (t = -.84, ns), longitudinal analysis does indicate a significant relationship between depression and metabolic syndrome over time (t = -5.20, p <.001). However, anxiety is not significantly related to metabolic syndrome when the relationship is examined through cross-sectional analysis (t = -1.51, ns) and longitudinal analysis (&#967;² = 13.83, ns). Similarly, social support is not significantly related to metabolic syndrome when examined in cross-sectional (&#967;² = .63, ns) and longitudinal (t = 1.53, ns) analysis. Although level of stress is not significantly related to metabolic syndrome as a whole, there is a significant relationship between stress and both triglyceride level (t = -2.94, p = .003) and blood glucose level (t = -3.26, p = .001). digital.library.unt.edu/ark:/67531/metadc11005/
Metabolism of Hydrocortisone by X-Irradiated Rat Liver Tissue as Determined by the Porter-Silber Chromagen Method
The present study may be considered endocrinological and radiobiological in nature. The endocrinology phase was concerned with studying the changes in endocrine function following the application of a stress agent. X-irradiation was chosen as the stressor in order to determine any difference in effect of this stressor from others which have been studied, e. g. heat, cold, metabolic poisons. Liver slices taken from rats at various time intervals following whole body X-irradiation were tested for their ability to metabolize hydrocortisone from a Krebs-Ringer solution. digital.library.unt.edu/ark:/67531/metadc108062/
Metabolism of Methylglyoxal by Scenedesmus Quadricauda
The purpose of this study was to investigate the metabolic pathways of methylglyoxal in S. quadricauda. digital.library.unt.edu/ark:/67531/metadc131263/
Metacognition, Motivation, and Learning: A Study of Sixth-Grade Middle School Students' Use and Development of Self-Regulated Learning Strategies
This study investigated whether students can be taught to use self-regulated strategies. digital.library.unt.edu/ark:/67531/metadc278191/
The MetaCombine Project
This poster presentation discusses the MetaCombine project, a Mellon-funded effort based at Emory University, with the goal of discovering and developing systems and methods to more meaningfully combine digital libraries, digital library resources, and digital library services. digital.library.unt.edu/ark:/67531/metadc81391/
Metadata Analysis at the Command-Line
This article discusses metadata analysis tools, processes, and methodologies aimed at helping to focus limited quality control resources on the areas of the collection where they might have the most benefit. digital.library.unt.edu/ark:/67531/metadc157309/
Metadata and XML
This presentation discusses how XML can help store metadata. The University of North Texas (UNT) Digital Projects Unit developed the UNTL metadata element set with IndexData that tailored the data to meet their needs. digital.library.unt.edu/ark:/67531/metadc28339/
A Metadata Approach to Preservation of Digital Resources: The University of North Texas Libraries' Experience
Article discussing metadata approaches to preservation of digital resources and the experiences of the University of North Texas (UNT) Libraries. digital.library.unt.edu/ark:/67531/metadc29308/
Metadata: Batch Editing of MARC Records (work area D)
Report for an Institute of Museum and Library Sciences (IMLS) Grant Partner Uplift Project. This reports workflows developed for the conversion of two sets of metadata records and serves the following objectives: research different avenues for the batch import and export of MARC records from popular integrated library systems, identify tools/software which aids in batch editing of MARC records, and document workflow for batch editing MARC records. digital.library.unt.edu/ark:/67531/metadc29820/
Metadata Enhancements and Quality Assurance Mechanisms
Abstract document accompanying a poster presentation for the 2008 ALISE Annual Conference (Work in Progress session. The topic is maintaining usable and sustainable digital collections using a complex set of actions and some of the tools and quality assurance mechanisms used at the University of North Texas (UNT) Libraries. digital.library.unt.edu/ark:/67531/metadc39334/
Metadata Enhancements and Quality Assurance Mechanisms [Poster]
This poster presentation was presented at the 2008 Association for Library and Information Science Education (ALISE) conference (Work in Progress session). The poster discusses that maintaining usable and sustainable digital collections requires a complex set of actions, and demonstrates some of the tools and quality assurance mechanisms used at the UNT Libraries. digital.library.unt.edu/ark:/67531/metadc39319/
Metadata for ETD Lifecycle Management
Chapter from Guidance Documents for Lifecycle Management of ETDs. This chapter describes the roles of metadata in facilitating the ETD lifecycle, methods to capture metadata manually and automatically, examples of programs using metadata to enhance ETD access, and strategies to manage metadata over time. digital.library.unt.edu/ark:/67531/metadc279711/
Metadata Madness: Quality Issues in Metadata Management
This presentation provides an introductory discussion on metadata quality issues. It outlines factors that influence metadata quality including the resource types, local requirements, collaborators' requirements, and cost issues and addresses how to manage metadata quality. digital.library.unt.edu/ark:/67531/metadc29295/
Metadata Quality: A Phased Approach to Ensuring Long-Term Access to Digital Resources
Paper accompanying a poster presentation at the 2009 ASIS&T Annual Meeting. This paper discusses metadata quality and a phased approach to ensuring long-term access to digital resources. digital.library.unt.edu/ark:/67531/metadc29318/
Metadata Quality: A Phased Approach to Ensuring Long-Term Access to Digital Resources [Poster]
Poster presented at the 2009 ASIS&T Annual Meeting. This poster discusses how an effective metadata management approach can help institutions improve consistency, clarity of lineage, and relationships to that they can better use, reuse, and integrate resources. digital.library.unt.edu/ark:/67531/metadc29287/
Metadata Quality Assurance: The University of North Texas Libraries' Experience
Presentation on issues related to metadata quality management and demonstrates a number of tools, workflows, and quality assurance mechanisms employed by the University of North Texas (UNT) Libraries' Digital Projects Unit. digital.library.unt.edu/ark:/67531/metadc29301/
Metadata Quality Assurance: The University of North Texas Libraries' Experience
Article on metadata quality assurance and the experience of the University of North Texas (UNT) Libraries. digital.library.unt.edu/ark:/67531/metadc29320/
Metadata Quality Enhancement for Large Digital Collections: Web Browser Automation with Selenium IDE
Poster presented at the 2012 TCDL Annual Conference. This poster discusses metadata quality enhancement for large digital collections. digital.library.unt.edu/ark:/67531/metadc86138/
Metadata to fit your needs... How much is too much?
This presentation briefly introduces the University of North Texas (UNT) Libraries and their mission. It explains the structure of the Digital Projects Unit having the Digital Library and The Portal to Texas History, and discusses their metadata structure and its role in Digital Projects. digital.library.unt.edu/ark:/67531/metadc28356/
Metadata Tools and Workflows at the University of North Texas
This presentation illustrates the metadata tools, workflows, and quality control measures at the University of North Texas (UNT) Libraries' Digital Projects Unit. digital.library.unt.edu/ark:/67531/metadc29304/
Metadata Training Needs Assessment: Final Report
Report prepared for the Texas Digital Library (TDL) Metadata Working Group (MWG). In this report, the focus is on the project that was tasked in creating metadata course/modules for beginners and experts alike. digital.library.unt.edu/ark:/67531/metadc226885/
Metal-Aluminum Oxide Interactions: Effects of Surface Hydroxylation and High Electric Field
Metal and oxide interactions are of broad scientific and technological interest in areas such as heterogeneous catalysis, microelectronics, composite materials, and corrosion. In the real world, such interactions are often complicated by the presence of interfacial impurities and/or high electric fields that may change the thermodynamic and kinetic behaviors of the metal/oxide interfaces. This research includes: (1) the surface hydroxylation effects on the aluminum oxide interactions with copper adlayers, and (2) effects of high electric fields on the interface of thin aluminum oxide films and Ni3Al substrate. X-ray photoelectron spectroscopy (XPS) studies and first principles calculations have been carried out to compare copper adsorption on heavily hydroxylated a- Al2O3(0001) with dehydroxylated surfaces produced by Argon ion sputtering followed by annealing in oxygen. For a heavily hydroxylated surface with OH coverage of 0.47 monolayer (ML), sputter deposition of copper at 300 K results in a maximum Cu(I) coverage of ~0.35 ML, in agreement with theoretical predictions. Maximum Cu(I) coverage at 300 K decreases with decreasing surface hydroxylation. Exposure of a partially dehydroxylated a-Al2O3(0001) surface to either air or 2 Torr water vapor results in recovery of surface hydroxylation, which in turn increases the maximum Cu(I) coverage. The ability of surface hydroxyl groups to enhance copper binding suggests a reason for contradictory experimental results reported in the literature for copper wetting of aluminum oxide. Scanning tunneling microscopy (STM) was used to study the high electric field effects on thermally grown ultrathin Al2O3 and the interface of Al2O3 and Ni3Al substrate. Under STM induced high electric fields, dielectric breakdown of thin Al2O3 occurs at 12.3 } 1.0 MV/cm. At lower electric fields, small voids that are 2-8 A deep are initiated at the oxide/metal interface and grow wider and deeper into the metal substrate, which eventually leads to either physical collapse or dielectric breakdown of the oxide film on top. digital.library.unt.edu/ark:/67531/metadc3039/
Metal Complexes of 2,3-Quinoxalinedithiol
A series of new planar complexes with the dianion of 2,3-quinoxalinedithiol ligand has been prepared. The complexes have been characterized from the study of their analyses, magnetic moment, conductance, polarograms, electron spin resonance spectra, and electronic spectra, and compared with the available data on the corresponding maleonitriledithiolene and toluene-3,4-dithiolene complexes. digital.library.unt.edu/ark:/67531/metadc164322/
Metal (II) Complexes with N-Salicylideneamino Acids
Transition metal complexes derived from Schiff bases have rendered an important contribution to the development of modern coordination chemistry. Various stable compounds have been prepared having synthetic, biological, and physicochemical interest. In particular, complexes of salicylaldimines, B-ketoamines, and closely related ligand systems have been investigated. digital.library.unt.edu/ark:/67531/metadc164341/
Metal Oxide Reactions in Complex Environments: High Electric Fields and Pressures above Ultrahigh Vacuum
Metal oxide reactions at metal oxide surfaces or at metal-metal oxide interfaces are of exceptional significance in areas such as catalysis, micro- and nanoelectronics, chemical sensors, and catalysis. Such reactions are frequently complicated by the presence of high electric fields and/or H2O-containing environments. The focus of this research was to understand (1) the iron oxide growth mechanism on Fe(111) at 300 K and 500 K together with the effect of high electric fields on these iron oxide films, and (2) the growth of alumina films on two faces of Ni3Al single crystal and the interaction of the resulting films with water vapor under non-UHV conditions. These studies were conducted with AES, LEED, and STM. XPS was also employed in the second study. Oxidation of Fe(111) at 300 K resulted in the formation of Fe2O3 and Fe3O4. The substrate is uniformly covered with an oxide film with relatively small oxide islands, i.e. 5-15 nm in width. At 500 K, Fe3O4 is the predominant oxide phase formed, and the growth of oxide is not uniform, but occurs as large islands (100 - 300 nm in width) interspersed with patches of uncovered substrate. Under the stress of STM induced high electric fields, dielectric breakdown of the iron oxide films formed at 300 K occurs at a critical bias voltage of 3.8 ± 0.5 V at varying field strengths. No reproducible result was obtained from the high field stress studies of the iron oxide formed at 500 K. Ni3Al(110) and Ni3Al(111) were oxidized at 900 K and 300 K, respectively. Annealing at 1100 K was required to order the alumina films in both cases. The results demonstrate that the structure of the 7 Å alumina films on Ni3Al(110) is k-like, which is in good agreement with the DFT calculations. Al2O3/Ni3Al(111) (γ'-phase) and Al2O3/Ni3Al(110) (κ-phase) films undergo drastic reorganization and reconstruction, and the eventual loss of all long-range order upon exposure to H2O pressure > 10-5 Torr. Al2O3/Ni3Al(110) film is significantly more sensitive to H2O vapor than the Al2O3/Ni3Al(111) film, and this may be due to the incommensurate nature of the oxide/Ni3Al(110) interface. STM measurements indicate that this effect is pressure- rather than exposure- dependent, and that the oxide instability is initiated at the oxide surface, rather than at the oxide/metal interface. The effect is not associated with formation of a surface hydroxide, yet is specific to H2O (similar O2 exposures have no effect). digital.library.unt.edu/ark:/67531/metadc4843/
Metallization and Modification of Low-k Dielectric Materials
Aluminum was deposited onto both Teflon AF and Parylene AF surfaces by chemical vapor deposition of trimethylaluminum. This work shows that similar thin film (100 Angstroms) aluminum oxide adlayers form on both polymers at the low temperature dosing conditions used in the studies. Upon anneal to room temperature and above, defluorination of the polymer surfaces increased and resulted in fluorinated aluminum oxide adlayers; the adlayers were thermally stable to the highest temperatures tested (600 K). Angle-resolved spectra showed higher levels of fluorination toward the polymer/adlayer interface region. Copper films were also deposited at low temperature onto Teflon AF using a copper hexafluoroacetylacetonate-cyclooctadiene precursor. Annealing up to 600 K resulted in the loss of precursor ligands and a shift to metallic copper. As with aluminum adlayers, some polymer defluorination and resulting metal (copper) fluoride was detected. Parylene AF and polystyrene films surfaces were modified by directly dosing with water vapor passed across a hot tungsten filament. Oxygen incorporation into polystyrene occurred exclusively at aromatic carbon sites, whereas oxygen incorporation into parylene occurred in both aromatic and aliphatic sites. Oxygen x-ray photoelectron spectra of the modified polymers were comparable, indicating that similar reactions occurred. The surface oxygenation of parylene allowed enhanced reactivity toward aluminum chemical vapor deposition. Silicon-carbon (Si-Cx) films were formed by electron beam bombardment of trimethylvinylsilane films which were adsorbed onto metal substrates at low temperatures in ultra-high vacuum. Oxygen was also added to the films by coadsorbing water before electron beam bombardment; the films were stable to more than 700 K, with increasing silicon-oxygen bond formation at elevated temperatures. Copper metal was sputter deposited in small increments onto non-oxygenated films. X-ray photoelectric spectra show three-dimensional copper growth (rather than layer-by-layer growth), indicating only weak interaction between the copper and underlying films. Annealing at elevated temperatures caused coalescence or growth of the copper islands, with spectra indicating metallic copper rather than copper oxide. digital.library.unt.edu/ark:/67531/metadc9754/
Metals in Chemistry and Biology: Computational Chemistry Studies
Numerous enzymatic reactions are controlled by the chemistry of metallic ions. This dissertation investigates the electronic properties of three transition metal (copper, chromium, and nickel) complexes and describes modeling studies performed on glutathione synthetase. (1) Copper nitrene complexes were computationally characterized, as these complexes have yet to be experimentally isolated. (2) Multireference calculations were carried out on a symmetric C2v chromium dimer derived from the crystal structure of the [(tBu3SiO)Cr(µ-OSitBu3)]2 complex. (3) The T-shaped geometry of a three-coordinate β-diketiminate nickel(I) complex with a CO ligand was compared and contrasted with isoelectronic and isosteric copper(II) complexes. (4) Glutathione synthetase (GS), an enzyme that belongs to the ATP-grasp superfamily, catalyzes the (Mg, ATP)-dependent biosynthesis of glutathione (GSH) from γ-glutamylcysteine and glycine. The free and reactant forms of human GS (wild-type and glycine mutants) were modeled computationally by employing molecular dynamics simulations, as these currently have not been structurally characterized. digital.library.unt.edu/ark:/67531/metadc3678/
Metamodeling-based Fast Optimization of Nanoscale Ams-socs
Modern consumer electronic systems are mostly based on analog and digital circuits and are designed as analog/mixed-signal systems on chip (AMS-SoCs). the integration of analog and digital circuits on the same die makes the system cost effective. in AMS-SoCs, analog and mixed-signal portions have not traditionally received much attention due to their complexity. As the fabrication technology advances, the simulation times for AMS-SoC circuits become more complex and take significant amounts of time. the time allocated for the circuit design and optimization creates a need to reduce the simulation time. the time constraints placed on designers are imposed by the ever-shortening time to market and non-recurrent cost of the chip. This dissertation proposes the use of a novel method, called metamodeling, and intelligent optimization algorithms to reduce the design time. Metamodel-based ultra-fast design flows are proposed and investigated. Metamodel creation is a one time process and relies on fast sampling through accurate parasitic-aware simulations. One of the targets of this dissertation is to minimize the sample size while retaining the accuracy of the model. in order to achieve this goal, different statistical sampling techniques are explored and applied to various AMS-SoC circuits. Also, different metamodel functions are explored for their accuracy and application to AMS-SoCs. Several different optimization algorithms are compared for global optimization accuracy and convergence. Three different AMS circuits, ring oscillator, inductor-capacitor voltage-controlled oscillator (LC-VCO) and phase locked loop (PLL) that are present in many AMS-SoC are used in this study for design flow application. Metamodels created in this dissertation provide accuracy with an error of less than 2% from the physical layout simulations. After optimal sampling investigation, metamodel functions and optimization algorithms are ranked in terms of speed and accuracy. Experimental results show that the proposed design flow provides roughly 5,000x speedup over conventional design flows. Thus, this dissertation greatly advances the state-of-the-art in mixed-signal design and will assist towards making consumer electronics cheaper and affordable. digital.library.unt.edu/ark:/67531/metadc115081/
Metamorphosis: William Faulkner's Incorporation of Short Stories into Longer Narratives
This study analyzes these stories in their original and later forms, both to discover the types of changes Faulkner made and to determine whether or not he followed any pattern in the revisions. digital.library.unt.edu/ark:/67531/metadc108116/
“A Metaphor for the Impossibility of Togetherness”: Expansion Processes in Gubaidulina’s First String Quartet
This thesis illustrates how I hear processes of expansion organizing musical materials in the First String Quartet. By employing a flexible approach to expansion and developing models of wedge and additive expansions beyond the bounds of specific voice-leading or rhythmic augmentation procedures, expansion processes can be understood in each of the varied episodes of the quartet. Gubaidulina’s use of expansion processes, embodied organically in pitch, rhythm, form, and physical space, unifies the episodic materials of the First String Quartet and provides an inevitable conclusion to the work’s loose narrative. digital.library.unt.edu/ark:/67531/metadc149671/
Metaphors, Myths, and Archetypes: Equal Paradigmatic Functions in Human Cognition?
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The overview of contributions to metaphor theory in Chapters 1 and 2, examined in reference to recent scholarship, suggests that the current theory of metaphor derives from long-standing traditions that regard metaphor as a crucial process of cognition. This overview calls to attention the necessity of a closer inspection of previous theories of metaphor. Chapter 3 takes initial steps in synthesizing views of domains of inquiry into cognitive processes of the human mind. It draws from cognitive models developed in linguistics and anthropology, taking into account hypotheses put forth by psychologists like Jung. It sets the stage for an analysis that intends to further understanding of how the East-West dichotomy guides, influences, and expresses cognitive processes. Although linguist George Lakoff denies the existence of a connection between metaphors, myths, and archetypes, Chapter 3 illustrates the possibility of a relationship among these phenomena. By synthesizing theoretical approaches, Chapter 3 initiates the development of a model suitable for the analysis of the East-West dichotomy as exercised in Chapter 4. As purely emergent from bodily experience, however, neither the concept of the East nor the concept of the West can be understood completely. There exist cultural experiences that may, depending on historical and social context, override bodily experience inclined to favor the East over the West because of the respective connotations of place of birth of the sun and place of death of the sun. This kind of overriding cultural meaning is based on the &#8220;typical, frequently recurring and widely shared interpretations of some object, abstract entity, or event evoked in people as a result of similar experiences. To call these meanings &#8216;cultural meanings' is to imply that a different interpretation is evoked in people with different characteristic experiences. As such, various interpretations of the East-West image-schema exist simultaneously in mutually exclusive or competing forms, as the analysis of Gatsby and the reversal of the values of East and West in the context of colonizing and counter-colonizing attitudes suggests. digital.library.unt.edu/ark:/67531/metadc3284/
A Method for Approximating the Distributed Loads of an Airplane by Sets of Point Loads
This paper gives the derivation of a method for determining the forces to be applied to these points which will simulate the load distributed over all the airplane. digital.library.unt.edu/ark:/67531/metadc107936/
A Method for Calculating Foil Depression Factors
As disc-shaped detectors are one of the primary means of measuring the neutron density, a better solution is desirable if the error due to the depression factor is to be made negligible. In this paper, an attempt is made to solve this problem in the oblate spheroidal co-ordinate system which most nearly describes the disc-shaped detector, so that solutions may be obtained that describe depression factors for detectors of varying thicknesses and radii. digital.library.unt.edu/ark:/67531/metadc130315/
A Method of Analyzing Linear Perspective for Presentation to Junior and Senior High School Students
The general purpose of this study is to develop a series of peep shows, or visual models, which will enable the young student to understand what the laws of perspective are, how they were found, and why his drawings will appear to have three dimensions if he follows the rules. The study is based upon a widely accepted idea--that it is much easier for most people to understand and remember a principle when they can actually see how it works. When rules are merely memorized, one is not assisted by reason, which is essential for useful retention. digital.library.unt.edu/ark:/67531/metadc96896/
A Method of Analyzing Trends in Modern Painting for Presentation to High-School Students
In developing the study, the writer has attempted to devise a method whereby high-school students may gain an understanding of certain trends in modern abstract and non-objective painting. digital.library.unt.edu/ark:/67531/metadc75684/