Degree Level

Lipidomic Analysis of Single Cells and Organelles Using Nanomanipulation Coupled to Mass Spectrometry (open access)

Lipidomic Analysis of Single Cells and Organelles Using Nanomanipulation Coupled to Mass Spectrometry

The capability to characterize disease states by way of determining novel biomarkers has led to a high demand of single cell and organelle analytical methodologies due to the unexpected heterogeneity present in cells of the same type. Lipids are of particular interest in the search for biomarkers due to their active roles in cellular metabolism and energy storage. Analyzing localized lipid chemistry from individual cells and organelles is challenging however, due to low analyte volume, limited discriminate instrumentation, and common requirements of separation procedures and expenditure of cell sample. Using nanomanipulation in combination with mass spectrometry, individual cells and organelles can be extracted from tissues and cultures in vitro to determine if heterogeneity at the cellular level is present. The discriminate extraction of a single cell or organelle allows the remainder of cell culture or tissue to remain intact, while the high sensitivity and chemical specificity of mass spectrometry provides structural information for limited volumes without the need for chromatographic separation. Mass analysis of lipids extracted from individual cells can be carried out in multiple mass spectrometry platforms through direct-inject mass spectrometry using nanoelectrospray-ionization and through matrix-assisted laser/desorption ionization.
Date: May 2016
Creator: Bowman, Amanda
System: The UNT Digital Library
Application of the Correlation Consistent Composite Approach to Biological Systems and Noncovalent Interactions (open access)

Application of the Correlation Consistent Composite Approach to Biological Systems and Noncovalent Interactions

Advances in computing capabilities have facilitated the application of quantum mechanical methods to increasingly larger and more complex chemical systems, including weakly interacting and biologically relevant species. One such ab initio-based composite methodology, the correlation consistent composite approach (ccCA), has been shown to be reliable for the prediction of enthalpies of formation and reaction energies of main group species in the gas phase to within 1 kcal mol-1, on average, of well-established experiment, without dependence on experimental parameterization or empirical corrections. In this collection of work, ccCA has been utilized to determine the proton affinities of deoxyribonucleosides within an ONIOM framework (ONIOM-ccCA) and to predict accurate enthalpies of formation for organophosphorus compounds. Despite the complexity of these systems, ccCA is shown to result in enthalpies of formation to within ~2 kcal mol-1 of experiment and predict reliable reaction energies for systems with little to no experimental data. New applications for the ccCA method have also been introduced, expanding the utility of ccCA to solvated systems and complexes with significant noncovalent interactions. By incorporating the SMD solvation model into the ccCA formulation, the Solv-ccCA method is able to predict the pKa values of nitrogen systems to within 0.7 pKa unit (less …
Date: May 2015
Creator: Riojas, Amanda G.
System: The UNT Digital Library

Forging Pathways: A Multi-Case Study of Individuals with Intellectual Disability Pursuing Postsecondary Education at the Community College

This multi-case study sought to better understand how students with intellectual disability (ID) are forging pathways to higher education via the community college. Five individuals with ID who accessed higher education via the community college and their parents/guardians were interviewed. Each case provided insight into personal pathways with results given in case descriptions and individual case themes. Cross-case analysis revealed four themes positively impacting the college-going pathway for students with ID: value-driven grit, pathway knowledge, community support, and accessibility. Based on findings from this study, families appear to be the primary systems forging pathways to the community college for individuals with ID. Local education agencies and community colleges can assist these families by engaging in interagency collaboration, evaluating their systems, and aligning practices to the goal of students with ID accessing and engaging in higher education.
Date: December 2021
Creator: Jackson, Amanda O.
System: The UNT Digital Library
Relevance Thresholds: A Conjunctive/Disjunctive Model of End-User Cognition as an Evaluative Process (open access)

Relevance Thresholds: A Conjunctive/Disjunctive Model of End-User Cognition as an Evaluative Process

This investigation identifies end-user cognitive heuristics that facilitate judgment and evaluation during information retrieval (IR) system interactions. The study extends previous research surrounding relevance as a key construct for representing the value end-users ascribe to items retrieved from IR systems and the perceived effectiveness of such systems. The Lens Model of user cognition serves as the foundation for design and interpretation of the study; earlier research in problem solving, decision making, and attitude formation also contribute to the model and analysis. A self reporting instrument collected evaluative responses from 32 end-users related to 1432 retrieved items in relation to five characteristics of each item: topical, pertinence, utility, systematic, and motivational levels of relevance. The nominal nature of the data collected led to non-parametric statistical analyses that indicated that end-user evaluation of retrieved items to resolve an information problem at hand is most likely a multi-stage process. That process appears to be a cognitive progression from topic to meaning (pertinence) to functionality (use). Each step in end-user evaluative processing engages a cognitive hierarchy of heuristics that includes consideration (of appropriate cues), differentiation (the positive or negative aspects of those cues considered), and aggregation (the combination of differentiated cue aspects needed to …
Date: December 2000
Creator: Greisdorf, Howard F.
System: The UNT Digital Library
Glucose and Altered Ceramide Biosynthesis Impact the Transcriptome and the Lipidome of Caenorhabditis elegans (open access)

Glucose and Altered Ceramide Biosynthesis Impact the Transcriptome and the Lipidome of Caenorhabditis elegans

The worldwide rise of diabetes and obesity has spurred research investigating the molecular mechanisms that mediate the deleterious effects associated with these diseases. Individuals with diabetes and/or obesity are at increased risk from a variety of health consequences, including heart attack, stroke and peripheral vascular disease; all of these complications have oxygen deprivation as the central component of their pathology. The nematode Caenorhabditis elegans has been established as a model system for understanding the genetic and molecular regulation of oxygen deprivation response, and in recent years methods have been developed to study the effects of excess glucose and altered lipid homeostasis. Using C. elegans, I investigated transcriptomic profiles of wild-type and hyl-2(tm2031) ( a ceramide biosynthesis mutant) animals fed a standard or a glucose supplemented diet. I then completed a pilot RNAi screen of differentially regulated genes and found that genes involved in the endobiotic detoxification pathway (ugt-63 and cyp-25A1) modulate anoxia response. I then used a lipidomic approach to determine whether glucose feeding or mutations in the ceramide biosynthesis pathway or the insulin-like signaling pathway impact lipid profiles. I found that gluocose alters the lipid profile of daf-2(e1370) (an insulin-like receptor mutant) animals. These studies indicate that a transcriptomic …
Date: August 2016
Creator: Ladage, Mary Lee
System: The UNT Digital Library
Consequences of Coworker Bullying: A Bystander Perspective (open access)

Consequences of Coworker Bullying: A Bystander Perspective

Previous research on workplace bullying primarily focuses on two main actors – the bully and the victim – while neglecting a third actor: the bystander of the bullying. The prevalence of workplace bullying is increasing across organizations, resulting in more employees becoming subjected to the effects of workplace bullying. Furthermore, witnessing coworker-on-coworker bullying is likely to influence the relationships that the bystander has with the two coworkers involved in the bullying episode. Two areas are proposed to investigate their effect on the coworker bystander: coworker interpersonal justice and personal identification with coworkers. Coworker interpersonal justice involves the perceived fairness between coworkers, while personal identification refers to how these bystanders identify with the specific actors of the bullying event. In addition to work-related outcomes, bystanders are affected at a personal level. That is, being exposed to bullying situations causes these bystanders to alter their anxiety levels and their core affect, with core affect being a precursor to moods and emotions. In addition to the aforementioned outcomes of witnessing a coworker bullying incident, there are also contextual aspects which may influence these relationships. Personal-level factors, such as a bystander's empathy and sense of coherence (i.e., coping mechanisms), may influence the effect of …
Date: May 2017
Creator: Medina, Michele N.
System: The UNT Digital Library
Rebellion and Reconciliation: Social Psychology, Genre, and the Teen Film 1980-1989 (open access)

Rebellion and Reconciliation: Social Psychology, Genre, and the Teen Film 1980-1989

In this dissertation, I bring together film theory, literary criticism, anthropology and psychology to develop a paradigm for the study of teen films that can also be effectively applied to other areas of pop culture studies as well as literary genres. Expanding on Thomas Doherty's discussion of 1950s teen films and Ian Jarvie's study of films as social criticism, I argue that teen films are a discrete genre that appeals to adolescents to the exclusion of other groups. Teen films subvert social mores of the adult world and validate adolescent subculture by reflecting that subculture's values and viewpoints. The locus of this subversion is the means by which teenagers, through the teen films, vicariously experience anxiety-provoking adult subjects such as sexual experimentation and physical violence, particularly the extreme expressions of sex and violence that society labels taboo. Through analyzing the rhetoric of teen lifestyle films, specifically the teen romance and sex farce, I explore how the films offer teens vicarious experience of many adolescent "firsts." In addition, I claim that teen films can effectively appropriate other genres while remaining identifiable as teen films. I discuss hybrid films which combine the teen film with the science fiction genre, specifically Back to …
Date: December 1996
Creator: Hubbard, Christine Karen Reeves
System: The UNT Digital Library
Comparison and Application of Verismo Singing Concepts to Trumpet Performance through Aria Transcription and Emulation (open access)

Comparison and Application of Verismo Singing Concepts to Trumpet Performance through Aria Transcription and Emulation

The link between trumpet playing and emulation of the human voice has been acknowledged by a number of prominent teachers, authors, and composers since the inception of the trumpet as a melodic instrument. This dissertation is a pedagogical guide to lyrical trumpet performance based on the verismo style of singing consistent with the authentic interpretations of operatic soprano arias by Pietro Mascagni, Ruggero Leoncavallo, and Giacomo Puccini. Included are chapters that examine various aspects of the verismo style, as well as comparison and application of late 19th-century voice pedagogy to trumpet practice and performance. This resource examines six recordings of sopranos who created or popularized operatic roles during the verismo period. Included are transcriptions of the six arias for trumpet and piano, with performance notes based on dramatic and textual contexts, as well as interpretive aspects, namely tempo, dynamics, and vibrato.
Date: May 2021
Creator: Pratt, William (Trumpeter)
System: The UNT Digital Library
Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces (open access)

Biodiversity of Dragonflies and Damselflies (Odonata) of the South-Central Nearctic and Adjacent Neotropical Biotic Provinces

The south-central United States serves as an important biogeographical link and dispersal corridor between Nearctic and Neotropical elements of western hemisphere odonate faunas. Its species are reasonably well known because of substantial collections, but there has been no concerted effort to document the extent of biodiversity and possible geographic affinities of dragonflies and damselflies of this region. The recent discoveries of Argia leonorae Garrison, Gomphus gonzalezi Dunkle and Erpetogomphus heterodon Garrison from southern and western Texas and northern Mexico suggest that Odonata species remain to be discovered in this area, particularly from far south Texas and northern Mexico. I have documented a total of 12,515 records of Odonata found in 408 counties within the south-central U.S. A total of 73 species of damselflies and 160 species of dragonflies was revealed in the region. The 233 (197 in Texas) Odonata species are distributed among 10 families and 66 genera. Illustrated family, generic, and species-level keys are provided. Since the beginning of this work in the Fall of 1993, one species has been added each to the Louisiana and Oklahoma faunas, and 12 species have been added, previously unreported from Texas, including four new to the U.S. The area of highest Odonata …
Date: May 1999
Creator: Abbott, John C.
System: The UNT Digital Library

Exploring Enactments of Agency in Children's Literature from School Libraries

The purpose of this study was to analyze student-selected library books for how, if at all, agency is enacted by the characters. This study uses tenets from critical multicultural analysis (CMA) and elements of visual analysis (VA) to guide a critical content analysis of enactments of agency in the most circulated books from three school libraries during the 2019-2020 school year. This study builds on and extends the existing research on agency development in children and demonstrations of agency in children's literature. Data revealed a variety of characters, genre, and contexts within the identified books. Analysis provided evidence that characters in these child-selected books demonstrated enactments of agency in varying ways and degrees across all titles. Following a discussion that is organized around the themes created from the findings, characters are identified as belonging within one of the following agentic groups: activists, survivors, problem solvers, and friends. Implications for practice and research include further study of agency in characters of popular books, how children perceive enactments of agency of the characters, and the need for school librarians and other educators to understand agency development and acknowledging the agency of children as they make choices in the literature they read.
Date: August 2021
Creator: Loomis, Kathryn Barkley
System: The UNT Digital Library
Protesting the "Right" Way: Exploring Respectability Politics and Support for Black Lives Matter (open access)

Protesting the "Right" Way: Exploring Respectability Politics and Support for Black Lives Matter

Black Lives Matter gained elevated levels of support following the death of George Floyd at the hands of the Minneapolis Police Department. Despite temporary elevated levels of support, large segments of the populous are still reluctant and critical of the movement. This work aims to assess what role notions of respectability politics play in Black American support of Black Lives Matter. Respectability politics is consistently weaponized against members of oppressed groups including racial minorities, women, the LGBTQ community, and their related social movements. Analyzing the role of respectability politics in this context is a needed addition to the scholarly literature regarding social movement mobilization, as well as the interdisciplinary literature that has previously examined respectability in myriad forms. I hypothesize that unwillingness to support Black Lives Matter will be dependent on respectability politics as it relates to the perceived comportment and behavior police violence victims. This work included experimental analysis of the perceived respectability of a police brutality victim's "respectable" behavior being varied in the experimental treatment. I found support for my primary hypotheses that adherence to respectability politics correlated with diminished support for Black Lives Matter.
Date: July 2023
Creator: Goodwin, Alexander Isaac
System: The UNT Digital Library
Student preferences in screen design factors for Internet delivered college courses. (open access)

Student preferences in screen design factors for Internet delivered college courses.

Colleges and universities throughout the world are offering many of their courses via the Internet. Some institutions offer entire degrees online. This has ushered in a renewed interest in the debate on the effectiveness of non-traditional course delivery method. Numerous educational research studies have been conducted in an attempt to quantify that effectiveness. In any form of experimental research, control of variables is paramount. The rich multimedia capabilities of the World Wide Web give educators a wide variety of delivery media. However, with the exception of advice from artisans on design factors of the media, little research has been conducted with regard to the aesthetics of Web page design as viewed by the student. This study was conducted in an effort to establish student preferences with regard to two factors of Web page design as they might be used on those Web pages, background color and typeface used for text. In addition, it contains an analysis of whether or not there is an interaction between the two factors. Use of the results of this study should prove beneficial to both educators and educational researchers in their future endeavors.
Date: May 2003
Creator: Pineau, Joseph Roy
System: The UNT Digital Library
The Relationship of Sex and Age at Entrance to School to Second Grade Achievement (open access)

The Relationship of Sex and Age at Entrance to School to Second Grade Achievement

This investigation compared achievement of boys and girls in second grade who were seven years old in June, July, and August of 1983 to the boys and girls in second grade who were eight years old in September, October, and November of 1983. The students were tested using the Iowa Test of Basic Skills using the following areas: reading, total math, and composite scores. The study also looked at the correlation of sex and age of students who had been retained in first grade. A comparison of teacher grades to standardized test scores and ability grouping was also presented. One way analysis of variance was applied to the test results. A chi square test of independence was conducted on students retained in the first grade to determine if interaction between sex and age was indicated. Older children scored higher in all three areas measured, while girls scored higher in reading. This may seem contradictory, but is not. Age was significant beyond the .05 level, while sex was significant beyond the .001 level. This difference is explained by the extremes in means for younger boys and older girls. Since first grade curriculum emphasizes reading, this gave girls a definite advantage over …
Date: December 1986
Creator: Jernigan, Sharon Reynolds
System: The UNT Digital Library
Primary revenue streams of Hispanic-serving community colleges in Texas. (open access)

Primary revenue streams of Hispanic-serving community colleges in Texas.

This study examined the extent and sources of primary revenue for Hispanic-, African-American-, and Caucasian-serving public community colleges in Texas. The study also examined differences between and among primary revenue streams for these institutions. The public community colleges were identified as Hispanic-, African-American-, and Caucasian-serving based upon the percentage of enrollments for each ethnic classification. A comparative model was developed for the primary revenue streams of in-district student tuition, out-of-district student tuition differentials, out-of-state student tuition differentials, ad valorem property tax revenue per in-district contact hour, and state appropriations. Statistical Packages for the Social Sciences (SPSS) was utilized to conduct multiple-factor analysis of variance (ANOVA) on the data set to examine differences between and among the several variables. Post hoc tests were performed where necessary. Difference was identified in in-district student tuition. Post hoc analysis demonstrated that difference existed between Hispanic-serving and African-American-serving community colleges. No difference was identified in the remaining primary revenue streams.
Date: May 2005
Creator: Waller, Lee
System: The UNT Digital Library

Morale in the Western Confederacy, 1864-1865: Home Front and Battlefield

Access: Use of this item is restricted to the UNT Community
This dissertation is a study of morale in the western Confederacy from early 1864 until the Civil War's end in spring 1865. It examines when and why Confederate morale, military and civilian, changed in three important western states, Mississippi, Alabama, and Tennessee. Focusing on that time frame allows a thorough examination of the sources, increases the opportunity to produce representative results, and permits an assessment of the lingering question of when and why most Confederates recognized, or admitted, defeat. Most western Confederate men and women struggled for their ultimate goal of southern independence until Federal armies crushed those aspirations on the battlefield. Until the destruction of the Army of Tennessee at Franklin and Nashville, most western Confederates still hoped for victory and believed it at least possible. Until the end they drew inspiration from battlefield developments, but also from their families, communities, comrades in arms, the sacrifices already endured, simple hatred for northerners, and frequently from anxiety for what a Federal victory might mean to their lives. Wartime diaries and letters of western Confederates serve as the principal sources. The dissertation relies on what those men and women wrote about during the war - military, political, social, or otherwise - …
Date: May 2006
Creator: Clampitt, Brad R.
System: The UNT Digital Library
Some Things Change and the News Stays the Same: Contextual Factors of Mainstream News Viewing and Racial Attitudes (open access)

Some Things Change and the News Stays the Same: Contextual Factors of Mainstream News Viewing and Racial Attitudes

Considerable media research has established that much of mainstream, United States based news is historically rife with content that both implicitly and explicitly reinforces popular cultural norms. Combined with a history full of inequities towards marginalized groups, many of which were based on race, consumption of mainstream news has been linked to increased hostility and more negative attitudes towards non-Whites in the United States. That said, much of this work views news from a monolithic perspective of news programming, irrespective of the differences in political orientation or broadcast integrity. By using quantitative assessments of how various mainstream news programs score on both left/right and fact/opinion-based dichotomies, the purpose of the present study is to address these gaps. As models for how mainstream news consumption is related to existing race-related attitudes, theoretical foundations of cultivation theory (how long viewers watch), the motivation and opportunities model (if viewers are motivated in their viewing) and social ecology theory (who viewers are), were used in relation to these dichotomies. However, overall results suggest that, while time spent with news, race, and gender appear to affect news consumption's relationship with race-related attitudes, preference for left vs. right wing news and fact vs. opinion-based was less …
Date: August 2022
Creator: Archibald, Audon
System: The UNT Digital Library
The One Electron Basis Set: Challenges in Wavefunction and Electron Density Calculations (open access)

The One Electron Basis Set: Challenges in Wavefunction and Electron Density Calculations

In the exploration of chemical systems through quantum mechanics, accurate treatment of the electron wavefunction, and the related electron density, is fundamental to extracting information concerning properties of a system. This work examines challenges in achieving accurate chemical information through manipulation of the one-electron basis set.
Date: May 2016
Creator: Mahler, Andrew
System: The UNT Digital Library
A Philosophy and an Approach to Teaching Non-professional-track Violin Students (open access)

A Philosophy and an Approach to Teaching Non-professional-track Violin Students

The aim of this dissertation is to lay the groundwork for an integrated approach to violin instruction for children who are not being groomed explicitly for professional careers as instrumentalists. The study presents a particular focus on the age of middle school children, in order to showcase a more specialized and definitive result of research without, however, distinguishing between advantages and limitations of different age groups of children who study music and learn to play the violin. My first goal is to craft a sample method of teaching with a premise that not all students studying music must or need to become professional musicians in their future. I promote an approach based on the premise that music has universal value available to all and that any kind of music education encourages the growth, personality development, and imagination of children. My second goal is to explore how music education functions in 21st century western culture. Research is based on teachings and methods established by Suzuki, Kodaly, Jaques-Dalcroze, and Orff, among others.
Date: May 2014
Creator: Bard-Schwarz, Anna Ewa
System: The UNT Digital Library

Ethics in Technical Communication: Historical Context for the Human Radiation Experiments

Access: Use of this item is restricted to the UNT Community
To illustrate the intersection of ethical language and ethical frameworks within technical communication, this dissertation analyzes the history and documentation of the human radiation experiments of the 1940s through the 1970s. Research propositions included clarifying the link between medical documentation and technical communication by reviewing the literature that links the two disciplines from the ancient period to the present; establishing an appropriate historiography for the human radiation experiments by providing a context of the military, political, medical, and rhetorical milieu of the 1940s to the 1970s; closely examining and analyzing actual human radiation experiment documentation, including proposals, letters, memos, and consent forms, looking for established rhetorical constructions that indicate a document adheres to or diverts from specific ethical frameworks; and suggesting the importance of the human radiation documents for studying ethics in technical communication. Close rhetorical analysis of the documents included with this project reveals consistent patterns of metadiscourse, passive and nominal writing styles, and other rhetorical constructions, including negative language, redundancies, hedges, and intensifiers, that could lead a reader to misunderstand the writer's original ethical purpose. Ultimately this project finds that technical communicators cannot classify language itself as ethical or unethical; the language is simply the framework with which …
Date: August 2005
Creator: Audrain, Susan Connor
System: The UNT Digital Library
Group 10 Catalyzed Olefin Hydroarylation (open access)

Group 10 Catalyzed Olefin Hydroarylation

Alkyl-arenes are important industry feedstock chemicals that are used as solvents, pharmaceutical precursors, and polymer monomer units. One alkyl-arene, ethylbenzene, is the main focus of this dissertation, and is produced in the million ton a year scale. As alkyl-arenes are important commodity chemicals, catalytic olefin hydroarylation is a lucrative alternative for their production rather than Friedel-Crafts alkylation or various coupling reactions that have lower atom economy, require strong acids, or are energetically demanding. Currently catalytic olefin hydroarylation still suffers from decomposition pathways of the active catalytic complexes, side reactions that lead to waste products, and unfavorable activation barriers, which represent high temperature and pressure. Modifications to the catalytically active system bipyridine platinum(II) (bpyPtII), through computational methods, are explored herein. The work presented here investigates catalytic olefin hydroarylation in order to mitigate the aforementioned difficulties. Included in this study are changes to the electronic profile of the supporting ligand, bpy, through the addition of electron withdrawing or electron donating R groups (methoxy, nitro), definite ligand replacements such as bpy to hydridotris(pyrazolyl)borate (Tp), changes in metal oxidation (II to IV), and replacing the metal center from Pt to Ni. Nickel was selected as a possible alternative to platinum as it is more …
Date: December 2012
Creator: Gonzalez, Hector Emanuel
System: The UNT Digital Library
Quantum Chemistry Calculations of Energetic and Spectroscopic Properties of p- and f-Block Molecules (open access)

Quantum Chemistry Calculations of Energetic and Spectroscopic Properties of p- and f-Block Molecules

Quantum chemical methods have been used to model a variety of p- and f-block chemical species to gain insight about their energetic and spectroscopic properties. As well, the studies have provided understanding about the utility of the quantum mechanical approaches employed for the third-row and lanthanide species. The multireference ab initio correlation consistent Composite Approach (MR-ccCA) was utilized to predict dissociation energies for main group third-row molecular species, achieving energies within 1 kcal mol-1 on average from those of experiment and providing the first demonstration of the utility of MR-ccCA for third-row species. Multireference perturbation theory was utilized to calculate the electronic states and dissociation energies of NdF2+, providing a good model of the Nd-F bond in NdF3 from an electronic standpoint. In further work, the states and energies of NdF+ were determined using an equation of motion coupled cluster approach and the similarities for both NdF2+ and NdF were noted. Finally, time-dependent density functional theory and the static exchange approximation for Hartree-Fock in conjunction with a fully relativistic framework were used to calculate the L3 ionization energies and electronic excitation spectra as a means of characterizing uranyl (UO22+) and the isoelectronic compounds NUO+ and UN2.
Date: August 2016
Creator: South, Christopher James
System: The UNT Digital Library
The Multi-reference Correlation Consistent Composite Approach: A New Vista In Quantitative Prediction Of Thermochemical And Spectroscopic Properties (open access)

The Multi-reference Correlation Consistent Composite Approach: A New Vista In Quantitative Prediction Of Thermochemical And Spectroscopic Properties

The multi-reference correlation consistent composite approach (MR-ccCA) was designed to reproduce the accuracy of more computationally intensive ab initio quantum mechanical methods like MR-ACPF-DK/aug-cc-pCV?Z-DK, albeit at a significantly reduced cost. In this dissertation, the development and applications of the MR-ccCA method and a variant of its single reference equivalent (the relativistic pseudopotential ccCA method) are reported. MR-ccCA is shown to predict the energetic properties of reactive intermediates, excited states species and transition states to within chemical accuracy (i.e. ±1.0 kcal mol 1) of reliable experimental values. The accuracy and versatility of MR-ccCA are also demonstrated in the prediction of the thermochemical and spectroscopic properties (such as atomization energies, enthalpies of formation and adiabatic transition energies of spin-forbidden excited states) of a series of silicon-containing compounds. The thermodynamic and kinetic feasibilities of the oxidative addition of an archetypal arylglycerol ?-aryl ether (?-O-4 linkage) substructure of lignin to Ni, Cu, Pd and Pt transition metal atoms using the efficient relativistic pseudopotential correlation consistent composite approach within an ONIOM framework (rp-ccCA-ONIOM), a multi-level multi-layer QM/QM method formulated to enhance the quantitative predictions of the chemical properties of heavy element-containing systems larger than hitherto attainable, are also reported.
Date: December 2011
Creator: Oyedepo, Gbenga A.
System: The UNT Digital Library
A Comparison Study of Student Academic Performance by Male African American Students in a Traditional Public School and Male African American Students in a Single Gender Academy (open access)

A Comparison Study of Student Academic Performance by Male African American Students in a Traditional Public School and Male African American Students in a Single Gender Academy

A quantitative, causal-comparative study between single gender and traditional mixed gender schools was conducted to examine how single gender schooling affected the academic achievement of African American males in a high-poverty urban community. This study examined the differences in TSI and EOC scores between African American males who attended a single gender male high school and a traditionally mixed gender high school serving students in the same community in Fort Worth, Texas. A two sample t-test was used to compare the STAAR and TSI scores of the two groups of African American males. Microsoft Excel was used to collect the descriptive statistical data and analysis was conducted in SPSS version 25.0 for Windows. A detailed description of the participants, the research design that was used in the study, a description of instruments that was used to analyze the data, research problem, research questions on which the study was based, and a description of data analysis methods that was used. This quantitative research compared the STAAR and TSI scores in language arts, math, and reading. The findings of study indicate the single-gender school model impacts the academic achievement of African American males in a particular community in Fort Worth, Texas. The …
Date: May 2020
Creator: Walker, Carlos L
System: The UNT Digital Library
Exploring Naming Behavior in Personal Digital Image Collections: the Iconology and Language Games of Pinterest (open access)

Exploring Naming Behavior in Personal Digital Image Collections: the Iconology and Language Games of Pinterest

As non-institutional digital image collections expand into social media, independent non-professional image curators are emerging, actively constructing alternative naming conventions to suit their needs in a social collecting environment. This project considers how independent user-curators are developing particular sense-making behaviors as they actively contribute names to large, unstructured social image collections. In order to capture and explore this evolving language adaptation, Pinterest names are analyzed using a matrix composed of Panofsky’s three strata of subject matter, Rosch’s levels of categorical abstraction, Shatford Layne’s image attributes and Wittgenstein’s language game constructions. Analyzing Pinterest image names illuminates previously unnoticed behaviors by independent user-curators as they create shared collections. Exploring the various language choices which user-curators select as they apply this new curating vocabulary helps identify underlying user needs not apparent in traditionally curated collections restricted to traditional naming conventions.
Date: December 2014
Creator: Sutcliffe, Tami
System: The UNT Digital Library