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Design, Synthesis and Screening of Homoleptic and Heteroleptic Platinum(ii) Pyridylazolate Complexes for N-type Semiconducting and Light-emitting Devices
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A series of heteroleptic and homoleptic platinum(II) complexes has been synthesized and characterized towards their use in thin film devices such as organic light-emitting diodes (OLEDs) and organic thin film transistors (OTFTs). Pyridylpyrazolate- and pyridyltetrazolate-containing ligands were selected due to their structural rigidity and ease of functionalization. Single-crystal x-ray diffraction studies of two selected heteroleptic complexes show strong aggregation with preferential stacking into vertical columns with a varying degree of overlap of the neighboring square planar molecular units. It is shown that the close proximity of the molecules to one another in the stack increases semiconducting character, phosphorescence quantum yields, and shorter radiative lifetimes. The potential for these materials towards incorporation into high-efficiency doping free white OLEDs (DFW-OLEDs) for solid-state lighting and display applications has been realized and will be expanded upon by present and future embodiments of materials in this thesis. digital.library.unt.edu/ark:/67531/metadc283853/
Corrosion Protection of Aerospace Grade Magnesium Alloy Elektron 43™ for Use in Aircraft Cabin Interiors
Magnesium alloys exhibit desirable properties for use in transportation technology. In particular, the low density and high specific strength of these alloys is of interest to the aerospace community. However, the concerns of flammability and susceptibility to corrosion have limited the use of magnesium alloys within the aircraft cabin. This work studies a magnesium alloy containing rare earth elements designed to increase resistance to ignition while lowering rate of corrosion. The microstructure of the alloy was documented using scanning electron microscopy. Specimens underwent salt spray testing and the corrosion products were examined using energy dispersive spectroscopy. digital.library.unt.edu/ark:/67531/metadc283846/
Media and Corporate Social Responsibility: How Leading Business Magazines Frame a Controversial Concept
Corporate social responsibility (CSR) is an emerging concept that continues to play a controversial role in the business world. Different CSR theories and ethical foundations inform different approaches to embedding socially responsible behavior into today's business functions. As technology, globalization, and economic challenges change the corporate world, the meaning and application of CSR also changes. While no empirical evidence of CSR's impact on performance exists, many corporations operate under the assumption that CSR holds significant value. This study examines the framing of CSR in stories published by leading business magazines between 2008 and 2012. By examining the presentation of CSR concepts, the resulting analysis can provide important conclusions for corporations, public relations practitioners, mass media, and consumers. This study resulted in a hierarchical pyramid of frames that organizes the framing of CSR in business magazines into three layers: category, motivation, and classification as either responsible behavior or irresponsible behavior. These results lead to recommendations for future CSR research, including the need for quantitative evidence of a connection or disconnection between CSR and profitability. digital.library.unt.edu/ark:/67531/metadc283861/
Is It More Advantageous to Administer Libqual+® Lite Over Libqual+®? an Analysis of Confidence Intervals, Root Mean Square Errors, and Bias
The Association of Research Libraries (ARL) provides an option for librarians to administer a combination of LibQUAL+® and LibQUAL+® Lite to measure users' perceptions of library service quality. LibQUAL+® Lite is a shorter version of LibQUAL+® that uses planned missing data in its design. The present study investigates the loss of information in commonly administered proportions of LibQUAL+® and LibQUAL+® Lite when compared to administering LibQUAL+® alone. Data from previous administrations of LibQUAL+® protocol (2005, N = 525; 2007, N = 3,261; and 2009, N = 2,103) were used to create simulated datasets representing various proportions of LibQUAL+® versus LibQUAL+® Lite administration (0.2:0.8, 0.4:0.6. 0.5:0.5, 0.6:0.4, and 0.8:0.2). Statistics (i.e., means, adequacy and superiority gaps, standard deviations, Pearson product-moment correlation coefficients, and polychoric correlation coefficients) from simulated and real data were compared. Confidence intervals captured the original values. Root mean square errors and absolute and relative biases of correlations showed that accuracy in the estimates decreased with increase in percentage of planned missing data. The recommendation is to avoid using combinations with more than 20% planned missing data. digital.library.unt.edu/ark:/67531/metadc283825/
Confirming the Constructs of the Adlerian Personality Priority Assessment (Appa)
The primary purpose of this study was to confirm the four-factor structure of the 30-item Adlerian Personality Priority Assessment (APPA) using a split-sample cross-validation confirmatory factor analysis (CFA). The APPA is an assessment, grounded in Adlerian theory, used to conceptualize clients based on the four personality priorities most commonly used in the Adlerian literature: superiority, pleasing, control, and comfort. The secondary purpose of this study was to provide evidence for discriminant validity, examine predictive qualities of demographics, and explore the prevalence of the four priorities across demographics. For the cross validation CFA, I randomly divided the sample, 1210 undergraduates, at a large public research university (53% Caucasian, 13.1% Hispanic/Latino(a), 21.4% African American, 5.4% American Indian, and 5.8% biracial; mean age =19.8; 58.9% females), into two equal subsamples. I used Subsample 1 (n = 605) to conduct the initial CFA. I held out Subsample 2 (n = 605) to test any possible model changes resulting from Subsample 1 results and to provide further confirmation of the APPA's construct validity. Findings from the split-sample cross-validation CFA confirmed the four-factor structure of the APPA and provided support for the factorial/structure validity of the APPA's scores. Results also present initial evidence of discriminant validity and support the applicability of the instrument across demographics. Overall, these findings suggest Adlerian counselors can confidently use the APPA as a tool to conceptualize clients. digital.library.unt.edu/ark:/67531/metadc283856/
Military-diplomatic Adventurism: Communist China's Foreign Policy in the Early Stage of the Korean War (1950-1951)
The thesis studies the relations of Communist China's foreign policy and its military offensives in the battlefield in Korean Peninsula in late 1950 and early 1951, an important topic that has yet received little academic attention. As original research, this thesis cites extensively from newly declassified Soviet and Chinese archives, as well as American and UN sources. This paper finds that an adventurism dominated the thinking and decision-making of Communist leaders in Beijing and Moscow, who seriously underestimated the military capabilities and diplomatic leverages of the US-led West. The origin of this adventurism, this paper argues, lays in the CCP's civil war experience with their Nationalist adversaries, which featured a preference of mobile warfare over positional warfare, and an opportunist attitude on cease-fire. This adventurism ended only when Communist front line came to the verge of collapse in June 1951. digital.library.unt.edu/ark:/67531/metadc283814/
A Performer's Guide to Béla Bartók's Violin Concerto No 1, Opus Posthumous, 1907–1908
Despite Bartók's lasting international fame, some of his works remain unjustly lesser-known. One of the pieces that still resides in relative obscurity is his Violin Concerto No.1—a gem of the violin repertoire that must be brought to the broader public's attention. The fact that the concerto was hidden definitely contributed to its little–known status at first. However, the most important cause for the lack of enthusiasm to tackle this terrific work lies in the unorthodox demands it puts on the violinist. The purpose of this paper is to provide musical and technical suggestions based on Bartók's performing style and on his requirements for performer, which will help to create a more persuasive interpretation of the piece. The guide covers the questions of character, articulation, dynamics, and other performance aspects, and also provides practical suggestions, such as fingerings and bowings. It is hoped that this study will help violin performers to gain additional knowledge and insight into this composition and encourage more frequent performances of it. digital.library.unt.edu/ark:/67531/metadc283828/
Synthetic and Structural Chemistry of Ligand-substituted Triosmium Clusters and a Rhenium(i) Complex
The reaction of 2-[(diphenylphosphino)methyl]-6-methylpyridine (PN) with Os3(CO)12-n(MeCN)n [where n = 0 (1), 1 (2), 2 (3)] has been investigated. Os3(CO)12 reacts with PN in the presence of Me3NO to afford the clusters Os3(CO)11(1-PN) (4) and 1,2-Os3(CO)10(1-PN)2 (5). X-ray diffraction analyses confirm the equatorial coordination of the phosphine(s) in 4 and 5, with the two phosphines in the latter cluster exhibiting a 1,2-trans orientation about the Os-Os vector that contains the two ligands. Treatment of the MeCN-substituted cluster Os3(CO)11(MeCN) and PN (1:1 ratio) in CH2Cl2 gives clusters 4 and 5, in addition to HOs3(η1-Cl)(CO)10(1-PN) (6) as a result of competitive activation of the reaction solvent. Cluster 6 contains 48e- and the diffraction structure reveals the presence of axial chloride and equatorial phosphine ligands which are located on adjacent osmium atoms. The bridging hydride ligand in 6 spans the Cl,P-substituted Os-Os vector. The reaction of Os3(CO)10(MeCN)2 with PN furnishes 5, 6, and 1,1-Os3(CO)10(2-PN) (7) in yields that are dependent on the reagent stoichiometry and reaction solvent. The solid-state structure of 7 confirms the chelation of the PN ligand to a single osmium atom via the pyridine and phosphine moieties at axial and equatorial sites, respectively. The bonding in 7 relative to other possible stereoisomers has been explored by DFT calculations, and the diffraction structure is computed as the thermodynamically most stable form of this cluster. Cluster 4 is photosensitive and CO loss gives 7, in addition to the formation of the dihydride H2Os3(CO)8[µ-CH(NC5H3)CH2PPh2] (8), whose origin derives from the double metalation of the C-6 methyl group of the PN ligand in 7. Photolysis of 7 yields 8 without detectable observation of the expected intermediate hydride HOs3(CO)9[µ-CH2(NC5H3)CH2PPh2]. The PN ligand in 7 undergoes P-C bond activation in toluene at 110 °C to afford the 50e cluster Os3(CO)9(µ-C6H4)(µ-PPh), which contains face-capping benzyne and phosphinidene moieties. The bonding between the benzyne moiety and the opened Os3 frame in 9 has been examined computationally, and these data are discussed relative to and π bonding contributions from the metalated aryl ring to the cluster polyhedron. Thermolysis of BrRe(CO)5 with 4-(2,2-dimethylhydrazino)dimethylhydrazone-3(Z)-penten-2-one in toluene at 70 °C furnishes the new β-diketimine-substituted complex fac-BrRe(CO)3[(Me2NNCMe)2CH2] (1) in 50-70 isolated yield. Product 1 is also obtained in comparable yield when the same reactants are irradiated at 366 nm at room temperature in fluid solution. Treatment of the parent ligand with the "lightly stabilized" rhenium compound fac-BrRe(CO)3(THF)2 affords 1 as the sole observable rhenium product. Complex 1 has been characterized in solution by IR and 1H NMR spectroscopy, and the molecular structure has been determined by single-crystal X-ray diffraction analysis. digital.library.unt.edu/ark:/67531/metadc283850/
Fear of Alzheimer's Disease in Middle to Late Adulthood: a Two Year Investigation of Change Versus Stability
The term dementia refers to a progressive decline in cognitive functioning resulting in a significant impairment in daily living. Given the devastating impacts of the disease and lack of a cure, it is reasonable to expect people fear developing a dementia. Alzheimer's disease ranks high among the most feared diseases in national samples of the American population. As a topic of study, little is known about the determinants of fear of Alzheimer's disease and how this fear may change as a function of aging, time, or experience. The current study sought to fill this gap by investigating the nature of changes in fear of Alzheimer's disease by following participants (N = 227) over the course of two years. Volunteers completed measures on fear of dementia, knowledge about Alzheimer's disease, knowledge about the aging process, personality traits, memory self-efficacy, anxiety about aging, and Alzheimer's-related experiences (i.e., family history, caregiving experience, number of people known with the disease, personal diagnosis, etc.). Results supported the notion that fear for becoming a burden to others, a component of fear of dementia, decreased over the two years. In addition, personality traits and memory self-efficacy mediated the two-year change in concerns about perceived symptoms of cognitive decline. In predicting fear for various aspects of Alzheimer's disease, anxiety about aging and experience/exposure to the disease emerged as prominent predictors. These results highlight dementia concerns and offer guidance for early interventions, such as an open communication with family and health care providers about fear of dementia. digital.library.unt.edu/ark:/67531/metadc283854/
Female Psychopathy Predictors: Cluster B Traits and Alexithymia
Psychopathy has long been lauded as a premier predictor of negative behavioral outcomes because of its demonstrated associations with violence, antisocial conduct, and institutional maladjustment. Traditional conceptualizations of psychopathy highlight the relatively equal importance placed on personality features (i.e., a grandiose, deceitful interpersonal style and deficits in affective experience) and behavioral elements (i.e., an impulsive and irresponsible lifestyle marked by social deviance) of the syndrome. However, little research to date has investigated psychopathy dimensions in female samples, particularly as they relate to maladaptive behaviors beyond forensic settings. The current study comprehensively examined personality (i.e., Axis II Cluster B traits and alexithymia) and behavioral (i.e., suicide-related behavior and aggression) expressions of psychopathy in a sample of female inpatients recruited from trauma and dual-diagnosis units at a psychiatric hospital in Dallas, Texas. Contrary to expectations, the essential components of psychopathy in female psychiatric patients emphasized APD and NPD traits over features of HPD and BPD, which were relatively similar to elements traditionally highlighted in male psychopathy. On this point, two latent dimensions comprehensively addressed female psychopathy in the current sample: impulsive antisociality and narcissistic and histrionic interpersonal style. Interestingly, psychopathy (M r = .01) and Cluster B traits (M r = .05) were virtually unrelated to suicide-related behavior in female patients with trauma and substance use histories, but APD and BPD traits were more discerning for impulsive and premeditated aggression than variants of psychopathy. Aggression's relationship to BPD traits is at least partially mediated by alexithymia. These results are discussed in terms of improving evaluation and intervention efforts aimed at identifying and managing psychopathic females beyond forensic settings. digital.library.unt.edu/ark:/67531/metadc283811/
The Enemy of My Enemy Is What, Exactly? the British Flanders Expedition of 1793 and Coalition Diplomacy
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The British entered the War of the First Coalition against Revolutionary France in 1793 diplomatically isolated and militarily unprepared for a major war. Nonetheless, a French attack on the Dutch Republic in February 1793 forced the British to dispatch a small expeditionary force to defend their ally. Throughout the Flanders campaign of 1793, the British expeditionary force served London as a tool to end British isolation and enlist Austrian commitment to securing British war objectives. The 1793 Flanders campaign and the Allied war effort in general have received little attention from historians, and they generally receive dismissive condemnation in general histories of the French Revolutionary Wars. This thesis examines the British participation in the 1793 Flanders campaign a broader diplomatic context through the published correspondence of relevant Allied military and political leaders. Traditional accounts of this campaign present a narrative of defeat and condemn the Allies for their failure to achieve in 1793 the accomplishments of the sixth coalition twenty years later. Such a perspective obscures a clear understanding of the reasons for Allied actions. This thesis seeks to correct this distortion by critically analyzing the relationship between British diplomacy within the Coalition and operations in Flanders. Unable to achieve victory on their own strength, the British used their expeditionary force in Flanders as diplomatic leverage to impose their objectives on the other powers at war with France. digital.library.unt.edu/ark:/67531/metadc283820/
An Examination of the Similarities and Differences Between Transformational and Authentic Leadership and Their Relationship to Followers' Outcomes
To date there is no comprehensive understanding of what leadership is, nor is there an agreement among different theorists on what a good or effective leader should be. The purpose of this dissertation is to examine the theoretical and empirical similarities and differences of two styles of leadership – transformational and authentic leadership. Follower outcomes, as well as, the effects of trust and psychological capital within these paradigms are of particular interest. Although theoretical differences are proposed for the leadership style, the extent of overlap suggests the need to more closely examine each theory. Pilot studies were created to validate original scenarios created for the study as well as to examine the validity and reliability of new measurement instruments. The dissertation is designed to determine whether the relationships between authentic leadership and a variety of follower outcomes including performance, affective commitment, satisfaction, trust, and organizational citizenship behavior are similar to those between transformational leadership and these outcomes. In addition, variables more unique to authentic leadership research including psychological capital and follower well-being were examined within both paradigms to determine whether their relationships are similar to each type of leadership style. An experimental study using Qualtrics was used to collect the data with the expectation that there would be significant differences in the two styles of leadership such that each explains unique variance in follower behavior. The results of this dissertation support the lack of perceptual difference between the two theories of leadership. The results of this experiment do not come completely unexpected because of the ethical overlap between the two styles of leadership. Although subjects in the experiment could differentiate authentic leadership from transformational leadership based on the manipulations, authentic leadership effects were not significantly different when compared to transformational leadership effects. As a result, analyses in my research do not support previous theoretical development of authentic leadership as a separate theory from transformational leadership. Consequently, lack of support for my hypotheses actually provides valuable information to the study of leadership and calls into question the continued pursuit of research on authentic leadership. Although this dissertation was constructed to investigate the differences between authentic leadership and transformational leadership relative to follower outcomes, results found for gender differences may highlight an additional component to these leadership paradigms not previously considered. digital.library.unt.edu/ark:/67531/metadc283823/
Mist and Microstructure Characterization in End Milling Aisi 1018 Steel Using Microlubrication
Flood cooling is primarily used to cool and lubricate the cutting tool and workpiece interface during a machining process. But the adverse health effects caused by the use of flood coolants are drawing manufacturers' attention to develop methods for controlling occupational exposure to cutting fluids. Microlubrication serves as an alternative to flood cooling by reducing the volume of cutting fluid used in the machining process. Microlubrication minimizes the exposure of metal working fluids to the machining operators leading to an economical, safer and healthy workplace environment. In this dissertation, a vegetable based lubricant is used to conduct mist, microstructure and wear analyses during end milling AISI 1018 steel using microlubrication. A two-flute solid carbide cutting tool was used with varying cutting speed and feed rate levels with a constant depth of cut. A full factorial experiment with Multivariate Analysis of Variance (MANOVA) was conducted and regression models were generated along with parameter optimization for the flank wear, aerosol mass concentration and the aerosol particle size. MANOVA indicated that the speed and feed variables main effects are significant, but the interaction of (speed*feed) was not significant at 95% confidence level. The model was able to predict 69.44%, 68.06% and 42.90% of the variation in the data for both the flank wear side 1 and 2 and aerosol mass concentration, respectively. An adequate signal-to-noise precision ratio more than 4 was obtained for the models, indicating adequate signal to use the model as a predictor for both the flank wear sides and aerosol mass concentration. The highest average mass concentration of 8.32 mg/m3 was realized using cutting speed of 80 Surface feet per minute (SFM) and a feed rate of 0.003 Inches per tooth (IPT). The lowest average mass concentration of 5.91 mg/m3 was realized using treatment 120 SFM and 0.005 IPT. The cutting performance under microlubrication is five times better in terms of tool life and two times better in terms of materials removal volume under low cutting speed and feed rate combination as compared to high cutting speed and feed rate combination. Abrasion was the dominant wear mechanism for all the cutting tools under consideration. Other than abrasion, sliding adhesive wear of the workpiece materials was also observed. The scanning electron microscope investigation of the used cutting tools revealed micro-fatigue cracks, welded micro-chips and unusual built-up edges on the cutting tools flank and rake side. Higher tool life was observed in the lowest cutting speed and feed rate combination. Transmission electron microscopy analysis at failure for the treatment 120 SFM and 0.005 IPT helped to quantify the dislocation densities. Electron backscatter diffraction (EBSD) identified 4 to 8 µm grain size growth on the machined surface due to residual stresses that are the driving force for the grain boundaries motion to reduce its overall energy resulting in the slight grain growth. EBSD also showed that (001) textured ferrite grains before machining exhibited randomly orientated grains after machining. The study shows that with a proper selection of the cutting parameters, it is possible to obtain higher tool life in end milling under microlubrication. But more scientific studies are needed to lower the mass concentration of the aerosol particles, below the recommended value of 5 mg/m3 established by Occupational Safety and Health Administration (OSHA). digital.library.unt.edu/ark:/67531/metadc283858/
Quantifying Forest Vertical Structure to Determine Bird Habitat Quality in the Greenbelt Corridor, Denton, Tx
This study presents the integration of light detection and range (LiDAR) and hyperspectral remote sensing to create a three-dimensional bird habitat map in the Greenbelt Corridor of the Elm Fork of the Trinity River. This map permits to examine the relationship between forest stand structure, landscape heterogeneity, and bird community composition. A biannual bird census was conducted at this site during the breeding seasons of 2009 and 2010. Census data combined with the three-dimensional map suggest that local breeding bird abundance, community structure, and spatial distribution patterns are highly influenced by vertical heterogeneity of vegetation surface. For local breeding birds, vertical heterogeneity of canopy surface within stands, connectivity to adjacent forest patches, largest forest patch index, and habitat (vegetation) types proved to be the most influential factors to determine bird community assemblages. Results also highlight the critical role of secondary forests to increase functional connectivity of forest patches. Overall, three-dimensional habitat descriptions derived from integrated LiDAR and hyperspectral data serve as a powerful bird conservation tool that shows how the distribution of bird species relates to forest composition and structure at various scales. digital.library.unt.edu/ark:/67531/metadc283803/
A Vehicle-collision Learning System Using Driving Patterns on the Road
Demand of automobiles are significantly growing despite various factors, steadily increasing the average number of vehicles on the road. Increase in the number of vehicles, subsequently increases the risk of collisions, characterized by the driving behavior. Driving behavior is influenced by factors like class of vehicle, road condition and vehicle maneuvering by the driver. Rapidly growing mobile technology and use of smartphones embedded with in-built sensors, provides scope of constant development of assistance systems considering the safety of the driver by integrating with the information obtained from the vehicle on-board sensors. Our research aims at learning a vehicle system comprising of vehicle, human and road by employing driving patterns obtained from the sensor data to develop better systems of safety and alerts altogether. The thesis focusses on utilizing together various data recorded by the in-built embedded sensors in a smartphone to understand the vehicle motion and dynamics, followed by studying various impacts of collision events, types and signatures which can potentially be integrated in a prototype framework to detect variations, alert drivers and emergency responders in an event of collision. digital.library.unt.edu/ark:/67531/metadc283807/
Synthetic Peptides Model Instability of Cardiac Myosin Subfragment-2
Hypertrophic cardiomyopathy (HCM), a heart-related abnormality, is the most prevalent cause of sudden death in young athletes at sporting events. A cluster of cardiomyopathy mutations are localized in β-cardiac myosin at the N-terminal region of subfragment-2. Using resonance energy transfer probes, a synthetic peptide model system was developed to study stability of the coiled coil (S2 fragment) structure by determining monomer-dimer equilibrium of the peptide. Fluorescence resonance energy transfer and MacroModel software suite were used to obtain distance measurements along with measurement of coiled coil formation. The model peptide was used to characterize the effects of disease-causing-mutations and examine potential candidate drugs (polyamines) to counteract effects of mutations causing HCM. Distance measurements between donor and acceptor probes obtained by computational simulation and fluorescence resonance energy transfer (FRET) were consistent. Measurements also agreed with simulations of unlabeled wildtype, indicating coiled coil structural stability of the peptide. Interaction of the site-specific antibody with the peptide strongly inhibited dimerization and destabilized coiled coil structure of the peptide. Presence of negatively charged glutamate residues in the region of subfragment-2 strongly suggested a potential interaction site for positively charged polyamines. Binding of certain polyamines, such as poly-L-Lysine 11 residues and poly-D-Lysine 17 residues, demonstrated the ability to enhance dimerization and improve stability of the coiled coil structure, while some other polyamines were shown to have insignificant impact on the structure. In an attempt to characterize the effect of HCM-causing-mutations, peptides containing E924K mutation and lethal mutation E930 deletion were synthesized. Fluorescence resonance probes were conjugated to the mutant peptides to determine coiled coil formation. Results obtained from both dynamic simulations and resonance energy transfer experiments indicated that these mutations strongly inhibit dimerization, and thus, destabilize coiled coil structure of the peptide. Further experiments were conducted using heterodimers containing a chain of wildtype and a chain of mutant peptide. Both E924K & Edel930 mutations destabilized coiled coil formation and prevented dimerization. This peptide model system would provide a promising tool for drug development targeting HCM-causing-mutations along the S2 region of myosin. digital.library.unt.edu/ark:/67531/metadc283844/
Blueline Concerto: Critical Essay
The purpose of this critical essay is two-fold. First, the essay presents a detailed critical analysis of my original composition, Blueline Concerto for bass trombone and wind ensemble. Second, using Blueline Concerto, the essay presents preliminary findings of my study to develop an approach to composing that takes into account the musicians' health, specifically regarding noise induced hearing loss (NIHL). Through various hypothesized composition- and orchestral-based approaches, I test effectiveness on changes in NIHL risk while also noting that artistic merit and compositional integrity is preserved. digital.library.unt.edu/ark:/67531/metadc283800/
A Study of Mechanisms to Engineer Fine Scale Alpha Phase Precipitation in Beta Titanium Alloy, Beta 21S
Metastable b-Ti alloys are titanium alloys with sufficient b stabilizer alloying additions such that it's possible to retain single b phase at room temperature. These alloys are of great advantage compared to a/b alloys since they are easily cold rolled, strip produced and can attain excellent mechanical properties upon age hardening. Beta 21S, a relatively new b titanium alloy in addition to these general advantages is known to possess excellent oxidation and corrosion resistance at elevated temperatures. A homogeneous distribution of fine sized a precipitates in the parent b matrix is known to provide good combination of strength, ductility and fracture toughness. The current work focuses on a study of different mechanisms to engineer homogeneously distributed fine sized a precipitates in the b matrix. The precipitation of metastable phases upon low temperature aging and their influence on a precipitation is studied in detail. The precipitation sequence on direct aging above the w solvus temperature is also assessed. The structural and compositional evolution of precipitate phase is determined using multiple characterization tools. The possibility of occurrence of other non-classical precipitation mechanisms that do not require heterogeneous nucleation sites are also analyzed. Lastly, the influence of interstitial element, oxygen on a precipitation during the oxidation of Beta 21S has been determined. The ingress of oxygen and its influence on microstructure have also been correlated to measured mechanical properties. digital.library.unt.edu/ark:/67531/metadc283838/
José Antonio Gómez´s Versos Para Órgano (Section I): a Practical Guide for Performance
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José Antonio Gómez is an important figure in Mexican music history and his works are considered representative of the beginning of Mexico´s Independent era. Some musicians are familiar with Gómez´s choral output but his organ music is rarely considered. Due to the lack of an edition of Gómez´s Versets for Organ, a practical guide was found needed to aid its performance. This study is based on performance, analysis, and direct work on the only known source for it. The first chapter, Introduction, presents the argument for an edited version of the first part of the manuscript as a performance guide. The second provides biographical information on the composer. The third chapter discusses the background for the original performance of the Versets for Organ. Chapter 4 provides performance considerations for the works. The edition of the manuscript is included in chapter 5. digital.library.unt.edu/ark:/67531/metadc283837/
Exploring Aspects of Korean Traditional Music in Young Jo Lee's Piano Honza Nori
Since the 1960s, several gifted Korean composers, including perhaps most notably Young Jo Lee (b. 1943), have been internationally acclaimed for their work. In Western countries, however, there has been a scarcity of academic studies examining the artistry of the music of these Korean composers. Nonetheless, as one of today's most recognized composers in Korea, Young Jo Lee has been invited to numerous international concerts, conferences, and festivals where his works have been played and discussed. A salient feature of his compositions is the fusion of Korean traditional music and the elements of Western compositions, such as in, for one distinctive example, his piano composition, Piano Honza Nori. This musical study describes and analyzes how Lee integrates Korean traditional elements with Western musical ideas in Piano Honza Nori. Results of this study will contribute to the limited literature on the analysis of contemporary piano composition that integrates Korean traditional elements. digital.library.unt.edu/ark:/67531/metadc283809/
Design and Application of Phased Array System
Since its invention, phased array has been extensively applied in both military and civil areas. The applications include target detecting and tracking, space probe communication, broadcasting, human-machine interfaces, and remote sensing. Although the phased array applications show a broad range of potential market, there are some limitations of phased array's development: high cost, complex structure, narrow bandwidth, and high power consumption. Therefore, novel ideas are needed to reduce these constraints. In this thesis, several new approaches about the design and application of phased array are presents. First, the principle of phased array and fundamental design equations are introduced. Second, a new application of phased array antenna for radar respiration measurement is presented. By integrating a 4×4 Butler matrix with four-element antenna array, there will be four distinct main beams in radiation pattern. This new approach can improve the measurement accuracy and realize a high detecting rate. Third, a compact phased array antenna system based on dual-band operations is introduced. Dual-band function can make N-antenna system obtain 2N unique radiation beams (N is an integer) and achieve a significant size reduction compared to the conventional single-band system. To verify the design concept, a four-element phased array antenna working at 5GHz and 8GHz is designed and fabricated. The measurement results make a good agreement with the simulations. Finally, a novel architecture of steering phase feeding network by using bi-directional series-fed topology is presented. This bi-directional series-fed network needs less phase shifters and realizes steering phase function by applying control voltage. digital.library.unt.edu/ark:/67531/metadc283830/
An Investigation of the Phase Model of Psychotherapy Across Therapeutic Orientations: Are Different Approaches Actually All That Different?
The current study investigated the process of change underlying two different evidence-based treatments that yield similar outcome effectiveness in the treatment of depression: Cognitive Therapy (CT) and Interpersonal Therapy (IPT). The phase model of psychotherapeutic change (Howard et al., 1993) change is used to provide both a theoretical and practical framework in which to assess different patterns of change across the treatment modalities. The phase model posits that recovery from distress occurs in three sequential stages: remoralization, remediation and rehabilitation. CT can be conceptualized as a treatment in which the primary focus is on the treatment of symptoms (remediation), whereas IPT can typically be conceptualized as focusing on interpersonal conflicts and functioning (rehabilitation). The study utilized the TDCRP dataset (Elkin et al., 1985). Survival analysis indicated no significant difference in terms of onset or pattern of improvement across treatment orientations. Chi square analyses indicated individuals treated with IPT spend significantly more time engaged in rehabilitation compared to their CT counterparts. Taken together, these findings represent evidence that the process of therapeutic change is similar, if not virtually identical, across therapeutic orientation. The analyses also indicate that the phases of therapy may not necessarily be mutually exclusive and sequential, but may instead represent co-occurring patterns of improvement which are not sequentially determined. digital.library.unt.edu/ark:/67531/metadc283862/
Development of Novel Semi-conducting Ortho-carborane Based Polymer Films: Enhanced Electronic and Chemical Properties
A novel class of semi-conducting ortho-carborane (B10C2H12) based polymer films with enhanced electronic and chemical properties has been developed. The novel films are formed from electron-beam cross-linking of condensed B10C2H12 and B10C2H12 co-condensed with aromatic linking units (Y) (Y=1,4-diaminobenzene (DAB), benzene (BNZ) and pyridine (PY)) at 110 K. The bonding and electronic properties of the novel films were investigated using X-ray photoelectron spectroscopy (XPS), UV photoelectron spectroscopy (UPS) and Mulliken charge analysis using density functional theory (DFT). These films exhibit site-specific cross-linking with bonding, in the pure B10C2HX films, occurring at B sites non-adjacent to C in the B10C2H12 icosahedra. The B10C2H12:Y films exhibit the same phenomena, with cross-linking that creates bonds primarily between B sites non-adjacent to C in the B10C2H12 icosahedra to C sites in the Y linking units. These novel B10C2HX: Y linked films exhibit significantly different electron structure when compared to pure B10C2HX films as seen in the UPS spectra. The valence band maxima (VBM) shift from - 4.3 eV below the Fermi level for pure B10C2HX to -2.6, -2.2, and -1.7 for B10C2HX:BNZ, B10C2HX:PY, and B10C2HX:DAB, respectively. The top of the valence band is composed of states derived primarily from the Y linking units, suggesting that the bottom of the conduction band is composed of states primarily from B10C2H12. Consequently these B10C2HX:Y films may exhibit longer electron-hole separation lifetimes as compared to pure B10C2HX films. This research should lead to an enhancement of boron carbide based neutron detectors, and is of potential significance for microelectronics, spintronics and photo-catalysis. digital.library.unt.edu/ark:/67531/metadc283826/
The Useful Arts
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This creative nonfiction dissertation is a series of braided narratives that chronicle the author's career as a trombonist in the John Smith Ensemble. As an amateur trombonist, the author is shocked to be hired as a professional musician for an orchestra that plays on PBS and at Carnegie Hall. She quickly realizes, however, that the job requires her to play the trombone quietly in front of an unplugged microphone while a CD recording of another, more talented trombonist is blasted out toward an unknowing audience. The job also requires the author to tour around America. The scenes of from this tour are braided with scenes wherein she reflects on her life as a professional fake musician and her past failed attempts at getting a job. digital.library.unt.edu/ark:/67531/metadc283812/
A Relationship-based Cross National Customer Decision-making Model in the Service Industry
In 2012, the CIA World Fact Book showed that the service sector contributed about 76.6% and 51.4% of the 2010 gross national product of both the United States and Ghana, respectively. Research in the services area shows that a firm's success in today's competitive business environment is dependent upon its ability to deliver superior service quality. However, these studies have yet to address factors that influence customers to remain committed to a mass service in economically diverse countries. In addition, there is little research on established service quality measures pertaining to the mass service domain. This dissertation applies Rusbult's investment model of relationship commitment and examines its psychological impact on the commitment level of a customer towards a service in two economically diverse countries. In addition, service quality is conceptualized as a hierarchical construct in the mass service (banking) and specific dimensions are developed on which customers assess their quality evaluations. Using, PLS path modeling, a structural equation modeling approach to data analysis, service quality as a hierarchical third-order construct was found to have three primary dimensions and six sub-dimensions. The results also established that a country's national economy has a moderating effect on the relationship between service quality and investment size, and service satisfaction on investment size. This study is the first to conceptualize and use the hierarchical approach to service quality in mass services. Not only does this study build upon the investment model to provide a comprehensive decision model for service organizations to increase their return on investment but also, provides a congruence of work between service quality and the investment model in the management and decision sciences discipline. digital.library.unt.edu/ark:/67531/metadc283834/
The Effects of the Texas Reading First Response to Intervention Program on Student Achievement and Campus Special Education Rates
The purpose of this study was to examine special education populations, special education reading achievement, and regular education reading achievement in relation to the implementation of the Reading First three-tiered model as a response to Intervention platform. The population for this study focused on rural schools with Grades K-3 in attendance. Schools participated in the reading first grant period of the 2003-2009 school years. Forty-seven Texas Reading First schools were compared to 47 campuses having similar populations, socioeconomic makeups, and grade structures. This study utilized quantitative research measures to evaluate the level of special education populations on Reading First campuses using a response to intervention model. Quantitative measures were also used to evaluate those same campuses achievement rates of both special education and regular education students on the Texas Assessment of Knowledge and Skills reading tests. The study's outcome data showed little to no statistic significance for the three research questions. However, the inferential statistics showed a decrease in the special education population of the Reading First schools. Inferential statistics also indicated both the special education and the regular education students showed growth on the Texas Assessment of Knowledge and Skills reading tests. The use of a response to intervention program can be effective in the reduction of special education students identified on school campuses. Response to intervention programs can boost achievement levels of students receiving special education services. Students not enrolled in special education can benefit from effective response to intervention services. digital.library.unt.edu/ark:/67531/metadc283855/
Endocrine Disruption of Levonorgestrel in Early-life Stages of Fathead Minnows, Pimephales Promelas
Pharmaceuticals have routinely been detected in the environment resulting in a growing concern about whether these drugs could elicit effects on aquatic organisms. The concerns are centered on the highly conserved nature of mammalian therapeutic targets in fish. These pharmaceuticals are found at very low levels in the environment, which can result in sub-lethal effects in aquatic organisms. Therefore, 28 d early-life stage studies were conducted on six pharmaceuticals to assess their impacts on survival and growth fathead minnow larvae. Two pharmaceuticals tested, carbamazepine and fenofibrate, resulted in no alterations to survival and growth. However, amiodarone, clozapine, dexamethasone, and levonorgestrel (LNG) reduced survival at concentrations tested with LNG being the most potent at 462 ng/L. Survival was increased with amiodarone and clozapine; however LNG significantly decreased growth at 86 ng/L. Therefore, the most potent pharmaceutical tested was the synthetic progestin LNG with survival and growth impacts at concentrations less than 1 μg/L. Further analysis was conducted by measuring specific endocrine related mRNA transcript profiles in FHM larvae following the 28 d ELS exposure to LNG. Transcripts of 3β-HSD, 20β-HSD, and FSH were significantly down-regulated following 28 d exposure to both 16.3 and 86.9 ng/L LNG. Also, CYP19a expression was significantly down-regulated at 86.9 and 2392 ng/L LNG. Subsequently, a second study examined time periods that may be most sensitive (e.g., windows of sensitivity) for FHM larvae exposed to LNG. Larvae were exposed to a single concentration of LNG (i.e. LOECgrowth of 86.2 ng/L as determined in the 28 d ELS study) for different time periods starting with fertilized egg through 28 dph. Growth and mRNA expression of the four differentially expressed transcripts from the first study were measured. Regardless of the duration of exposure, LNG significantly decreased growth in fathead minnow larvae at day 28. For both 20β-HSD and CYP19a, mRNA expression was decreased following exposure to LNG; however, these transcripts returned to baseline levels after removal of LNG. 3β-HSD and FSH showed similar trends after exposure to LNG with 7-14 d and 14-28 d exposures exhibiting a decrease in expression; however, FSH expression returned to baseline once removed for LNG exposure. Based on these data, 3β-HSD was the only transcript to remain down regulated after LNG exposure. Together these data suggest LNG can negatively impact FHM larval survival and growth, with significant alterations in endocrine related responses. However, these changes in endocrine related responses may not directly correlate to the changes in growth demonstrated with LNG exposure to fathead minnows. Therefore, additional research is warranted to ascertain additional mechanisms, either endocrine related or non-endocrine functions, related to changes in growth of larval fathead minnows. digital.library.unt.edu/ark:/67531/metadc283848/
Student Experiences and Expectations Related to the Vertical Transfer Process From Two Feeder Community Colleges of a Senior Institution
The purpose of this study was to understand the experiences and expectations of community college students attending Temple College and Central Texas College regarding what they may expect as part of the vertical transfer process in order to improve the likelihood of their persistence to graduation at Texas A&M University-Central Texas (TAMUCT). The target population was approximately 700 students enrolled in two feeder Texas community colleges who had expressed intent to transfer to TAMUCT. The response rate was 19%, and 136 useable surveys were used for analysis. The sample was 74% female, 45% White with the majority minority. To assess the relationships between community college experiences and transfer expectation variables, correlations and logistic regression were used. No linear relationships were found regarding gender, age, ethnicity, highest level of parents' education, the aspirational variables of highest academic degree intend to obtain at any college or university and at TAMUCT, and the feeder community college attended and the two scales. A statistically significant relationship was found between parental income level and reported community college experiences (F(4, 79) = 2.612, p = .042) and vertical transfer expectations (F(4, 52) = 3.318, p = .017). Community college students from lower socioeconomic backgrounds may utilize the community college to upper-level institution vertical transfer pathway as a way to obtain an affordable baccalaureate degree. Community colleges and university administrators need to continue working together to establish unique and creative ways to create seamless transitions for vertical transfer students utilizing the community college to upper-level institution pathway to degree completion. digital.library.unt.edu/ark:/67531/metadc283801/
Glucose As an Energy Source to Increase Self-control in Restrained Eaters
Research evidence is suggestive of a strength model of self-control, also known as ego depletion, in social psychological literature. Engaging in an initial task of self-control depletes a limited resource, resulting in less self-control on a subsequent, unrelated task. The strength model of self-control has been applied to many practical, everyday situations, such as eating behaviors among dieters. Newer studies suggest that blood glucose is the resource consumed during acts of self-control. Consuming glucose seems to "replete" individuals who have been depleted, improving performance and self-control. The current study aimed to examine the effects of ego-depletion on restrained eaters. The hypothesis was that restrained eaters who were depleted by a task of self-control would exhibit more disinhibition on a taste-test task than would restrained eaters who were not depleted. However, if the participants were given glucose following the depletion task, then their self-control would be "repleted" and they would exhibit similar control to that of the non-depleted participants. Contrary to expectations there were no differences between the groups in terms of total amount of cookies consumed. These results are inconsistent with a glucose model of self-control. Suggestions for future research and implications of the findings are discussed. digital.library.unt.edu/ark:/67531/metadc283842/
Values and Valuing in a College Population
Values and valuing behavior have many conceptualizations. Despite how they are defined, values have a significant impact on behavior and are idiosyncratic in nature. The present study reviewed values research and sought to explore values identification and successful valued living among an archived sample of university students. Specifically, in a convenience sample of 282 undergraduate students, variables that affect values identification and behavior such as ethnicity, gender, psychological distress, and psychological flexibility were identified. Results indicated that university students identified with more than one valued living domain (as measured by the PVQ) and that contextual factors such as ethnicity, gender, age, and religiosity/spirituality were associated with specific values endorsed. Furthermore, psychological distress, including depression and anxiety (as measured by the DASS) was negatively correlated with values purity – the extent to which values are freely chosen. Finally, psychological flexibility (low experiential avoidance as measured by the AAQ-2), predicted values purity and successful living in accordance with identified values, and the relationship between these two variables was mediated by psychological flexibility. digital.library.unt.edu/ark:/67531/metadc283808/
Environmental Philosophy and the Ethics of Terraforming Mars: Adding the Voices of Environmental Justice and Ecofeminism to the Ongoing Debate
Questions concerning the ethics of terraforming Mars have received some attention from both philosophers and scientists during recent decades. A variety of theoretical approaches have been supplied by a number of authors, however research pursuant to this thesis has indicated at least two major blindspots in the published literature on the topic. First, a broad category of human considerations involving risks, dangers, and social, political, and economic inequalities that would likely be associated with efforts to terraform Mars have been woefully overlooked in the published literature to date. I attempt to rectify that oversight by employing the interpretive lens of environmental justice to address questions of environmental colonialism, equality in terms of political participation and inclusion in decision making structures, risks associated with technological progressivism, and responses to anthropogenic climate change. Only by including the historically marginalized and politically disenfranchised "voices," of both humans and nonhumans, can any future plan to terraform Mars be deemed ethical, moral or just according to the framework provided by environmental justice. Furthermore, broader political inclusion of this sort conforms to what ecofeminist author Val Plumwood calls the "intentional recognition stance" and provides an avenue through which globally societies can include nonanthropocentric considerations in decision making frameworks both for questions of terraforming Mars and also for a more local, contemporary set of environmental issues. The second blindspot I seek to correct concerns motivations for attempting terraforming on Mars previously inadequately philosophically elaborated in the published discourse. Specifically, the nonanthropocentric considerations postulated in the second chapter by various authors writing about terraforming, and elaborated in third with regard to environmental justice, reach their culmination in an ecofeminist ethic of care, sustainability, reproduction, and healthy growth which I uniquely elaborate based on a metaphorical similarity to the relationship between a gardener and a garden. Although at first glance, this metaphor may appear overly domineering, or uncritically paternalistic, I argue a deep understanding of its implications will be eminently beneficial for discussions of what is moral, good, right, and just to do regarding not only whether or not to terraform Mars, but for contemporary environmental concerns as well. Ultimately, extreme caution and a robust precautionary principle are the moral prescriptions arrived at in this thesis for the near term future. Until a sustainable civilization and just society can be established and effectively maintained, efforts to terraform and colonize another planet are practically certain to produce as much that is undesirable as that which might be good. digital.library.unt.edu/ark:/67531/metadc283810/
Learning From Each Other: Narrative Explorations of Art Museum Self-guided Materials
By engaging in collaborative arts-based and arts-informed narrative inquiry with my six-year-old daughter, we explored self-guided materials in art museums in the North Texas area. Though the field of art museum education is becoming increasingly participatory, most academic research related to self-guided materials has fallen short of exploring visitors' experiences with these materials. Furthermore, the perspectives of children have been long overlooked in academic and, at times, institutional research about family experiences in museums. Over the course of nine months, my daughter and I visited art museums and engaged with their self-guided materials, ranging from audio tours to interactive galleries. During this time we created collaborative works of art based on our experiences, which acted as both data collection and analysis in preparation for writing narratives. Our narrative explorations allowed us each to better understand our collective experiences. Though this research specifically targets self-guided materials in art museums, any educator interested in intergenerational or collaborative family learning may find both our methodologies and our conclusions to be helpful in better understanding how narratives are essential to this type of learning. digital.library.unt.edu/ark:/67531/metadc283845/
Reliability of an On-line System to Assess Physical Activity Behaviors in an Active Group of Kinesiology Undergraduate Students
Engaging in muscle strengthening activities (MSA) as part of a physical activity program offers health benefits. Although the merits of physical activity are well documented, many adults fail to meet appropriate levels as recommended in the 2008 Physical Activity Guidelines for Americans (PAGA). To get a more complete understanding on an individual's physical activity behaviors, the Tracking Resistance Exercise and Strength Training (TREST) internet based survey was developed. The purpose of the current study was to determine the test-retest reliability of TREST items. Additionally, the prevalence of participants meeting the 2008 PAGA was reported by gender. The survey was completed approximately two weeks apart by 224 (52% male) undergraduate kinesiology students. Analysis of the survey items presented TREST as a reliable instrument in assessing an individual's physical activity behavior with a focus on MSA. Among the convenience sample of 445 participants (56% male) that completed the survey in assessment #1, 73% met the 2008 PAGA minimum recommendations for MSA (>=2 days/week) and aerobic activity (>= 150 min MVPA). A more complete MSA and MVPA criteria was established (requiring MSA of all seven major muscle groups) and only 32% of participants met this guideline. In general, men engaged in aerobic exercise and MSA more than women. These results cannot be generalized due the age, activity level, and education of the study's participants. Future studies should investigate the validity of TREST items among a sample of varying fitness levels, races/ethnicities, ages, and educational levels. digital.library.unt.edu/ark:/67531/metadc283847/
Tax Compliance in a Social Setting: the Influence of Norms, Perceptions of Fairness, and Trust in Government on Taxpayer Compliance
Many taxing authorities, including those in the United States (U.S.), rely on voluntary tax compliance and continually search for ways to increase tax revenues. Most of these methods are costly and labor intensive, such as audits and penalties for noncompliance. Prior tax compliance research has heavily investigated the influence that economic factors, such as tax rates and penalties, have on individual compliance intentions. However, economic models fail to fully predict individual tax compliance. Psychology literature suggests that social factors may also play an important role in individual tax compliance decisions. The purpose of this study is to examine the influence that social and psychological factors have on individuals' tax compliance intentions. Specifically, a model of taxpayer compliance is hypothesized that suggests that norms, perceived fairness of the tax system, and trust in government have a significant influence on compliance intentions. Results of a survey of 217 U.S. taxpayers found support for the influence of social factors on tax compliance. This research concludes that social norms have an indirect influence on compliance intentions through internalization as personal norms. Specifically, as the strength of social norms in favor of tax compliance increase, personal norms of tax compliance also increase, and this leads to a subsequent increase in compliance intentions. This dissertation also finds that trust in government and the perceived fairness of the tax system have a significant influence on compliance intentions. Supplemental analyses indicate that trust in government fully mediates the relationship between perceived fairness of the tax system and compliance intentions. This research offers several contributions to accounting literature and provides valuable insight for taxing authorities. First, this study examines taxpayer compliance from a psychological, rather than an economics driven, perspective. The suggested model of taxpayer compliance posits that social norms have a significant influence on compliance intentions. This information may help taxing authorities develop less costly and more effective strategies for increasing taxpayer compliance. This study also examines the influence that perceived fairness of the tax system has on compliance intentions. This is a widely debated topic in the media and social settings and may have a particularly strong influence on compliance intentions during these times of political and social arguments regarding tax equity. Finally, trust in government around the world has seen a continual decline. The results indicate that decreased trust in government and decreased perceived fairness of the tax system lead to decreased intention to comply with tax laws. Such information may help governments understand actions they can take to improve tax compliance. digital.library.unt.edu/ark:/67531/metadc283805/
Innovations in Musical Texture and Aural Perspective: Steven Mackey's See Ya Thursday for Solo Marimba
This dissertation and accompanying lecture recital explore the unique textural features in the works of Steven Mackey as exhibited in See Ya Thursday (1993).A rigorous formal, harmonic, and motivic analysis will highlight the compositional characteristics of textural structure and aural perspective that exist in the work. Illumination of these compositional elements can help to identify and minimize the technical complexities that exist within this piece for the performer. In addition, this document provides brief biographical information on Steven Mackey and his works, and on See Ya Thursday as it relates to other pieces in the advanced marimba literature. Finally, it is the aim of the author to add a resource to the relatively limited amount of research on Steven Mackey with this analysis of See Ya Thursday. digital.library.unt.edu/ark:/67531/metadc283817/
An Exploration of Teachers' Adoption of the Bring Your Own Technology Program
The purpose of this study was to explore teachers' concerns, use, and actual practices in their adoption of the bring your own technology (BYOT) initiative. Twelve secondary teachers in a private school setting participated in this study. The participants represented all content areas including reading, math, science, and electives. The private school was in its third year of implementing BYOT. This case study incorporated multiple methods to collect data to gain a better understanding of teachers' adoption of an innovation, BYOT. The concerns-based adoption model (CBAM) was used as a theoretical framework. All three CBAM tools provided data: the Stages of Concern Questionnaire (SoCQ), levels of use interview protocol (LoUIP), and the innovation configuration (IC) map. Twelve of the participants completed the SoCQ across three different points in time. Six of the twelve teachers participated in three one-on-one interviews, including the LoUIP. Additionally, six teachers were observed in their classrooms during instruction. After triangulating all pieces of data, the majority of teachers had highest concerns related to self. Teachers were concerned about their ability to implement the innovation and managing BYOT in their classroom. Four of the six teachers had a level of use (LoU) at mechanical, and two teachers had a LoU at routine. The teachers' LoU indicated that they are using BYOT in the classroom; however, the majority of teachers observed had adoption practices mostly in the non-ideal variations of IC. The teachers' LoU and IC indicated that teachers had implemented BYOT in their own way and not necessarily in alignment with the campus' vision or expectations. This case study had several limitations, including the small number of participants and the brevity of classroom observations. Additionally, this study was limited to one school setting. Recommendations for future research include exploring teachers' adoption of BYOT in various school settings (i.e., both public and private schools) and teachers at the elementary, middle, and high school levels. Researchers should consider exploring the impact of specific interventions and support on teachers' adoption. digital.library.unt.edu/ark:/67531/metadc283863/
The Integration of Western Techniques with East Asian Philosophies in Isang Yun's Quartett Für Horn, Trompete, Posaune Und Klavier
Korean composer Isang Yun (1917-1995) was one of the few successful Asian avant-garde composers to blend philosophical elements from East Asia with Western techniques such as the twelve-tone method, Hauptton, Hauptklang, and Umspielung. In addition to the integration of Western and Eastern influences, a significant feature of Yun´s compositional language, found throughout his oeuvre, is the application of East Asian philosophical tenets into his works. The purpose of this dissertation is to develop a greater understanding of Isang Yun's life and music, more specifically the Quartett für Horn, Trompete, Posaune und Klavier. The dissertation is divided into five chapters. The first chapter of the dissertation presents introductory data, including the purpose and significance of the study. The second chapter provides pertinent biographical facts about Isang Yun and his works, obtained through research of authoritative books, journal articles, and interviews. The third chapter offers references to traditional Korean brass instruments in terms of their historical background, structure, and timbre. In addition, it also focuses on the processes by which Yun incorporated the compositional techniques of Hauptton, Hauptklang, and Umspielung to the work and their relation to Tao philosophy. The fourth chapter consists of an analytical and stylistic study of the Quartett; Yun's compositional language and formal structure are examined based on a stylistic assessment of selected examples from the work. The fifth and last chapter is a conclusion. digital.library.unt.edu/ark:/67531/metadc283829/
Detection of Temporal Events and Abnormal Images for Quality Analysis in Endoscopy Videos
Recent reports suggest that measuring the objective quality is very essential towards the success of colonoscopy. Several quality indicators (i.e. metrics) proposed in recent studies are implemented in software systems that compute real-time quality scores for routine screening colonoscopy. Most quality metrics are derived based on various temporal events occurred during the colonoscopy procedure. The location of the phase boundary between the insertion and the withdrawal phases and the amount of circumferential inspection are two such important temporal events. These two temporal events can be determined by analyzing various camera motions of the colonoscope. This dissertation put forward a novel method to estimate X, Y and Z directional motions of the colonoscope using motion vector templates. Since abnormalities of a WCE or a colonoscopy video can be found in a small number of frames (around 5% out of total frames), it is very helpful if a computer system can decide whether a frame has any mucosal abnormalities. Also, the number of detected abnormal lesions during a procedure is used as a quality indicator. Majority of the existing abnormal detection methods focus on detecting only one type of abnormality or the overall accuracies are somewhat low if the method tries to detect multiple abnormalities. Most abnormalities in endoscopy images have unique textures which are clearly distinguishable from normal textures. In this dissertation a new method is proposed that achieves the objective of detecting multiple abnormalities with a higher accuracy using a multi-texture analysis technique. The multi-texture analysis method is designed by representing WCE and colonoscopy image textures as textons. digital.library.unt.edu/ark:/67531/metadc283849/
Computational Studies of Inorganic Systems with a Multiscale Modeling Approach: From Atomistic to Continuum Scale
Multiscale modeling is an effective tool for integrating different computational methods, creating a way of modeling diverse chemical and physical phenomena. Presented are studies on a variety of chemical problems at different computational scales and also the combination of different computational methods to study a single phenomenon. The methods used encompass density functional theory (DFT), molecular dynamics (MD) simulations and finite element analysis (FEA). The DFT studies were conducted both on the molecular level and using plane-wave methods. The particular topics studied using DFT are the rational catalyst design of complexes for C—H bond activation, oxidation of nickel surfaces and the calculation of interaction properties of carbon dioxide containing systems directed towards carbon dioxide sequestration studies. Second and third row (typically precious metals) transition metal complexes are known to possess certain electronic features that define their structure and reactivity, and which are usually not observed in their first-row (base metal) congeners. Can these electronic features be conferred onto first-row transition metals with the aid of non-innocent and/or very high-field ligands? Using DFT, the impact of these electronic features upon methane C—H bond activation was modeled using the dipyridylazaallyl (smif) supporting ligand for late, first-row transition metal (M) imide, oxo and carbene complexes (M = Fe, Co, Ni, Cu; E = O, NMe, CMe2). To promote a greater understanding of the process and nature of metal passivation, first-principles analysis of partially oxidized Ni(111) and Ni(311) surface and ultra-thin film NiO layers on Ni(111) was performed. A bimodal theoretical strategy that considers the oxidation process using either a fixed GGA functional for the description of all atoms in the system, or a perturbation approach, that perturbs the electronic structure of various Ni atoms in contact with oxygen by application of the GGA+U technique was applied. Binding energy of oxygen to the nickel surfaces, charge states of nickel and oxygen, and the preferred binding mode of oxygen to nickel were studied to gain a better understanding of the formation of oxide layers. Using density functional theory, the thermodynamic properties for developing interaction potentials for molecular dynamics simulations of carbon dioxide systems were calculated. The interactions considered are Ni + H2O, Ni + Ni, Ni + CO2, CO2 + CO2, CO2 + H2O and H2O + H2O. These systems were chosen as the possible interactions that can occur when carbon dioxide is stored in the ocean. Molecular dynamics simulations using the results from the DFT studies were also conducted. Finally, thermal conduction analysis was performed on layered functionally graded materials (FGM) subjected to thermal shock by sudden cooling of the material in order to investigate the results obtained from three different mixing laws: linear, quadratic, and half-order. The functionally graded material considered was a composite of nickel and carbon nanotubes at different compositions varying from two to five layers. The middle layers for the three to five layers are composed of graded (i.e., gradually changing) percentages of nickel and carbon nanotube. The thermal conductivity, specific heat and density for the composites were calculated depending on the percentages of materials in each layer, and assuming different rules of mixture. digital.library.unt.edu/ark:/67531/metadc283802/
Privacy Management for Online Social Networks
One in seven people in the world use online social networking for a variety of purposes -- to keep in touch with friends and family, to share special occasions, to broadcast announcements, and more. The majority of society has been bought into this new era of communication technology, which allows everyone on the internet to share information with friends. Since social networking has rapidly become a main form of communication, holes in privacy have become apparent. It has come to the point that the whole concept of sharing information requires restructuring. No longer are online social networks simply technology available for a niche market; they are in use by all of society. Thus it is important to not forget that a sense of privacy is inherent as an evolutionary by-product of social intelligence. In any context of society, privacy needs to be a part of the system in order to help users protect themselves from others. This dissertation attempts to address the lack of privacy management in online social networks by designing models which understand the social science behind how we form social groups and share information with each other. Social relationship strength was modeled using activity patterns, vocabulary usage, and behavioral patterns. In addition, automatic configuration for default privacy settings was proposed to help prevent new users from leaking personal information. This dissertation aims to mobilize a new era of social networking that understands social aspects of human network, and uses that knowledge to honor users' privacy. digital.library.unt.edu/ark:/67531/metadc283816/
Cooperation-induced Criticality in Neural Networks
The human brain is considered to be the most complex and powerful information-processing device in the known universe. The fundamental concepts behind the physics of complex systems motivate scientists to investigate the human brain as a collective property emerging from the interaction of thousand agents. In this dissertation, I investigate the emergence of cooperation-induced properties in a system of interacting units. I demonstrate that the neural network of my research generates a series of properties such as avalanche distribution in size and duration coinciding with the experimental results on neural networks both in vivo and in vitro. Focusing attention on temporal complexity and fractal index of the system, I discuss how to define an order parameter and phase transition. Criticality is assumed to correspond to the emergence of temporal complexity, interpreted as a manifestation of non-Poisson renewal dynamics. In addition, I study the transmission of information between two networks to confirm the criticality and discuss how the network topology changes over time in the light of Hebbian learning. digital.library.unt.edu/ark:/67531/metadc283813/
Altruism and Depression: Exploring This Relationship and the Mechanisms Behind It
The impact of environmental influences on depression has been well established by research. In particular, it is known that receiving/perceiving adequate social support has a protective influence on depression. Less is known about the protective benefits of providing support to others, namely in the form of altruistic, empathetic, or prosocial behavior. While research has shown that having altruistic attitudes and engaging in altruistic behaviors has a positive impact on physical health and mental well-being, studies on the association between altruistic attitudes and/or behavior and depression are limited. The present study examined the relationship between altruism and depression, and hypotheses were tested that allow for explanation of why altruism may protect against depression. A sample of 303 participants was recruited from the University of North Texas and the surrounding community. Participants completed an online survey that examined their altruistic activities, details regarding these activities, their prosocial attitudes, and their current level of depression. Results did not support that level of involvement in altruistic activities is directly related to depression severity. However, outcomes from involvement in altruistic activities, including sense of overburden from participating in altruistic activities, level of social interaction with other helpers and those helped during altruistic activities, and sense of life satisfaction and purpose gained from participating in altruistic activities, were significantly related to depression severity. These results suggest that participating in altruistic activities that are not perceived as overburdening may lead to outcomes that could positively impact depression. Limitations and directions for future research are discussed. digital.library.unt.edu/ark:/67531/metadc283819/
Automated Real-time Objects Detection in Colonoscopy Videos for Quality Measurements
The effectiveness of colonoscopy depends on the quality of the inspection of the colon. There was no automated measurement method to evaluate the quality of the inspection. This thesis addresses this issue by investigating an automated post-procedure quality measurement technique and proposing a novel approach automatically deciding a percentage of stool areas in images of digitized colonoscopy video files. It involves the classification of image pixels based on their color features using a new method of planes on RGB (red, green and blue) color space. The limitation of post-procedure quality measurement is that quality measurements are available long after the procedure was done and the patient was released. A better approach is to inform any sub-optimal inspection immediately so that the endoscopist can improve the quality in real-time during the procedure. This thesis also proposes an extension to post-procedure method to detect stool, bite-block, and blood regions in real-time using color features in HSV color space. These three objects play a major role in quality measurements in colonoscopy. The proposed method partitions very large positive examples of each of these objects into a number of groups. These groups are formed by taking intersection of positive examples with a hyper plane. This hyper plane is named as 'positive plane'. 'Convex hulls' are used to model positive planes. Comparisons with traditional classifiers such as K-nearest neighbor (K-NN) and support vector machines (SVM) proves the soundness of the proposed method in terms of accuracy and speed that are critical in the targeted real-time quality measurement system. digital.library.unt.edu/ark:/67531/metadc283843/
Ability of Offenders with Psychopathic Traits to Simulate Cognitive and Affective Empathy
The accurate assessment of psychopathy constitutes a critical component of forensic assessments addressing offender populations. Among the core characteristics of psychopathy, the interpersonal component of deception and empathic deficits are prominently observed in offenders with psychopathic traits. Given the negative consequences of being classified as a psychopath, offenders may be likely to minimize their psychopathic traits. In particular, no research has investigated whether offenders with psychopathic traits are able to simulate empathy in an effort to mask their cognitive or affective empathy deficits (e.g., lack of remorse about offenses). The present study aims to contribute to the literature with regard to the simulation of empathy. Using a mixed between- and within-subjects design, 81 male detainees were placed into (a) a low psychopathy group, (b) a moderate psychopathy group, or (c) a high psychopathy group based on the Psychopathy Checklist – Revised. For the within-subjects component, all offenders answered empathy questionnaires under genuine and simulation conditions. Results indicate the sample possessed cognitive empathy, but did not display affective empathy under genuine instructions. Under simulation instructions, participants significantly increased their scores on several empathy measures. The implications of simulated empathy and comparisons between groups regarding simulation abilities are discussed. digital.library.unt.edu/ark:/67531/metadc283859/
Challenge the Silence
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This collection of personal essays about incest, abuse, and depression explores the lasting effects of an invisible childhood. The essays follow the protagonist from the age of five to her early twenties. Her brother, at a young age, becomes sexually abusive of her and her sisters, and her parents fail to protect their daughters. The family is divided as the older girls strive to defend their little sisters, while their parents attempt to excuse their son. When her brother is finally sent away, the protagonist is left to salvage what remains of her relationships with her parents. digital.library.unt.edu/ark:/67531/metadc283840/
Between Comancheros and Comanchería: a History of Fort Bascom, New Mexico
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In 1863, Fort Bascom was built along the Canadian River in the Eroded Plains of Territorial New Mexico. Its unique location placed it between the Comanches of Texas and the Comancheros of the Sangre de Cristo Mountains. This post was situated within Comanchería during the height of the United States Army's war against the Southern Plains Indians, yet it has garnered little attention. This study broadens the scholarly understanding of how the United States Army gained control of the Southwest by examining the role Fort Bascom played in this mission. This includes an exploration of the Canadian River Valley environment, an examination of the economic relationship that existed between the Southern Plains Indians and the mountain people of New Mexico, and an account of the daily life of soldiers posted to Fort Bascom. This dissertation thus provides an environmental and cultural history of the Canadian River Valley in New Mexico, a social history of the men stationed at Fort Bascom, and proof that the post played a key role in the Army's efforts to gain control of the Southern Plains Indians. This study argues that Fort Bascom should be recognized as Texas' northern-most frontier fort. Its men were closer to the Comanche homeland than any Texas post of the period. Its records clearly show that the Army used Fort Bascom as a key forward base of operations against Comanches and Kiowas. An examination of Bascom's post returns, daily patrols, and major expeditions allows its history to provide a useful perspective on the nineteenth-century American Southwest. digital.library.unt.edu/ark:/67531/metadc283832/
Analyzing Patterns Within Academic and Legal Definitions: a Qualitative Content Analysis of the Term "Cyberbullying"
Regardless of culture or nation, students today are experiencing bullying via technology. With the rise of technology, this abuse has the ability to become more far-reaching, and more pervasive than ever. These students face oppression, and in some cases severe imbalances of power. Current research is being conducted and laws created based on varying operational and conception definitions of the term "cyberbullying." This study aims to analyze and provide a coherent definition for the term "cyberbullying" as it is used in research and legislation, especially in the context of today's educational environments. The results help shed light on the large variances in the term and suggestions are made to clarify the definition as the field continues to move forward. digital.library.unt.edu/ark:/67531/metadc283860/
Southern Roots, Western Foundations: the Peculiar Institution and the Livestock Industry on the Northwestern Frontier of Texas, 1846-1864
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This dissertation challenges Charles W. Ramsdell's needless war theory, which argued that profitable slavery would not have existed west of the 98th meridian and that slavery would have died a natural death. It uses statistical information that is mined from the county tax records to show how slave-owners on the northwestern frontier of Texas raised livestock rather than market crops, before and during the Civil War. This enterprise was so strong that it not only continued to expand throughout this period, but it also became the foundation for the recovery of the Texas economy after the war. digital.library.unt.edu/ark:/67531/metadc283818/
A Survey of the Solo and Chamber Works for Trumpet, Horn, Trombone, Euphonium and Tuba By the Hungarian Composer Frigyes Hidas
Hidas composed more than 135 compositions. Of these 135 compositions 67 feature the trumpet, horn, trombone, euphonium, and tuba in a solo setting, a homogenous chamber setting, or a heterogeneous chamber setting. The first section of this project presents the significance of the topic, state of research, and methodology. Chapter one provides a narrative detailing the collaboration of Hidas with Gusztáv Höna and László Szabó, Sr. Chapter two provides a brief description of characteristics found in Hidas' compositions. Appendix A and B provides a survey of the 67 works for brass instruments that Hidas composed. Included in this survey is information pertaining to the title, editor, publisher and date of publication, total measures, duration, ranges, degree of difficulty, clefs, special effects/techniques, instrumentation, dedications, analytical information, general comments, recordings, and rental details. digital.library.unt.edu/ark:/67531/metadc283827/
Resilience Among Middle School Students
Resilience is the ability to survive and persevere during difficult times. Resilient people also thrive after overcoming adversity. Adolescents have many developmental tasks to overcome in their quest to becoming adults. Difficulty with these tasks can lead to academic and personal failures. Adolescents with low resilience often struggle with low self-esteem. If students are identified early as having lower levels of resilience, professional school counselors have an opportunity to provide resilience-enhancing activities. Prior to middle school, students are assigned all of their classes. During middle school, students begin to select their elective courses which may be representative of their interests and current emotional status. By looking at students' elective courses, I looked for patterns of resilience that may help professional school counselors proactively identify students in need of additional guidance in order to be academically successful. This study utilized a convenience sample of middle school students enrolled in the 8th grade (N = 190) of a large suburban school district located in the southwest United States to measure levels of resilience and elective course enrollment. Gender of the participants was 107 females and 83 males. The students reported their ethnicity as 5.8% African American/Black, 11.1% Asian, 12.6% Hispanic, 1.1% Native American, 1.6% Pacific Islander, 59.5% Caucasian/White, and 8.4% multiracial. I measured resilience in this study using the Resilience Scale and comparisons based on elective course. Data analyses include descriptive statistics and ANOVAs. Based on a statistical significance criterion of p < .05, students enrolled in athletics scored significantly higher in resilience than did non-athletics students enrolled in physical education/outdoor education (p = .035). Additionally, Caucasian females were significantly less resilient than Caucasian males (p = .031). Limitations of the study, implications of the results for practice, and recommendations for future research are presented. digital.library.unt.edu/ark:/67531/metadc283857/