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 Collection: UNT Theses and Dissertations
Hispanic Representation in the Superintendency: Perceived Competencies and Organizational Outcomes That Benefit School Districts
This study assessed 40 factors often cited in literature to determine the extent that Hispanic superintendents perceive them as influential when accessing the superintendency. Eight Hispanic superintendents in Texas participated in this qualitative study, which was based on interviews as well as written responses to a survey. This study found that the factors considered most influential to these superintendents were their ability to communicate, self-perception/self-efficacy, and level of overall preparedness. These findings contrast with previous research indicating that race or ethnicity, mentoring, and career path are most influential. The study also identified factors related to race and ethnicity that most influenced a Hispanic's ability to access the superintendency, albeit to a lesser degree. These factors were the ability to serve as a Hispanic role model to students, ability to increase Hispanic students' academic performance, and the ability to speak a second language. Moreover, through analysis of a large number of survey responses the study examined the extent to which a superintendent's race or ethnicity is significant to addressing the needs of Hispanics. To assure this question a comparative analysis of Hispanics' and non-Hispanics competencies and organizational outcome was conducted. The results indicate that superintendents, in general, regardless of race or ethnicity, can acquire knowledge about the Hispanic culture, develop cultural competence, and produce outcomes that affect Hispanics. A Hispanic, however, who possesses the ability to speak Spanish and has authentic cultural experiences, can potentially provide unique competencies in serving Hispanics. Cultural competence with Hispanics, however, does not supersede the importance of a superintendent's overall effectiveness and ability to meet the needs of all students. Whereas other studies have addressed the significance of cultural competency in other institutions that serve the public, such as the healthcare industry, this study addressed cultural competency in public education. Progressive definitions of cultural competency included the extent to which outcomes met constituent needs for measuring cultural competency. The overall findings in this study suggest a need to develop preparation programs that result in culturally competent leaders, a need to revise state required certification requirements to reflect a need for cultural competence, and a need to revise locally-developed job postings/descriptions to indicate that the superintendent must provide culturally competent leadership. digital.library.unt.edu/ark:/67531/metadc283806/
Repetition and Difference: Parodic Narration in Kander and Ebb's "The Scottsboro Boys"
The American musical team John Kander and Fred Ebb created many celebrated works, yet musicologists have carried out little research on those works. This study examines the role of music in the parodic narration of Kander and Ebb's final collaboration, The Scottsboro Boys. Kander and Ebb use minstrelsy to tell the story of the historic Scottsboro Boys trials with actors portraying the Scottsboro Boys as minstrels; at the same time, they employ a number of devices to subvert minstrelsy stereotypes and thereby comment on racism. Drawing on African American literary theory, sociolinguistics, and Bakhtin's dialogism, this study illuminates how Signifyin(g), a rhetorical tradition used to encode messages in some African American communities, is the primary way the actors playing the Scottsboro Boys subvert through minstrelsy. This study not only contributes to the discussion of Signifyin(g) in African American musicals and theatre as a tool of subversion, but also provides an example of non-African American creators—Kander and Ebb—using Signifyin(g) devices. They use these in the music and the book; in particular, Kander and Ebb do some Signifyin(g) on Stephen Foster's plantation melodies. digital.library.unt.edu/ark:/67531/metadc283804/
Metabolic Engineering in Plants to Control Source/sink Relationship and Biomass Distribution
Traditional methods like pruning and breeding have historically been used in crop production to divert photoassimilates to harvested organs, but molecular biotechnology is now poised to significantly increase yield by manipulating resource partitioning. It was hypothesized that metabolic engineering in targeted sink tissues can favor resource partitioning to increase harvest. Raffinose Family Oligosaccharides (RFOs) are naturally occurring oligosaccharides that are widespread in plants and are responsible for carbon transport, storage and protection against cold and drought stress. Transgenic plants (GRS47, GRS63) were engineered to generate and transport more RFOs through the phloem than the wild type plants. The transgenic lines produced more RFOs and the RFOs were also detected in their phloem exudates. But the 14CO2 labeling and subsequent thin layer chromatography analysis showed that the RFOs were most likely sequestered in an inactive pool and accumulate over time. Crossing GRS47 and GRS63 lines with MIPS1 plants (that produces more myo-inositol, a substrate in the RFO biosynthetic pathway) did not significantly increase the RFOs in the crossed lines. For future manipulation of RFO degradation in sink organs, the roles of the endogenous α-galactosidases were analyzed. The alkaline α-galactosidases (AtSIP1 and AtSIP2 in Arabidopsis) are most likely responsible for digesting RFOs in the cytoplasm and may influence the ability to manipulate RFO levels in engineered plants. Atsip1/2 (AtSIP1/AtSIP2 double-knockout plants) were generated and phenotypically characterized based on seed germination patterns, flowering time, and sugar content to observe the impact on RFO sugar levels. The observations and analysis from these lines provide a basis for further insight in the manipulation of resource allocation between source and sink tissues in plants for future research. digital.library.unt.edu/ark:/67531/metadc283836/
The Role of Attachment in Perceptions of Interparental Conflict and Behavior Problems in Middle Childhood
The current study investigated the association of interparental conflict, parent-child attachment, and children's behavior problems in middle childhood. Although the effects of interparental conflict have been studied extensively, there has been little research done in the developmental period of middle childhood. This study examined the potential mediating role of the attachment relationship between parents and children in a community sample consisting of 86 two-parent families with at least one child between the ages of 8-11. Path modeling procedures indicated that attachment security serves as a mediator between interparental conflict and child behavior problems based on child reports. In particular, child-reported attachment security to the mother significantly mediated the association between children's perceptions of threat from interparental conflict and child-reported internalizing and inattentive/hyperactive symptoms. Child-reported attachment security to the father was not a significant mediator and mediation was not supported in parent-report models. The current findings have implications for families experiencing conflict and speak to the importance of attachment in the parent-child relationship when explaining the association between instances of interparental conflict and child behavioral outcomes. In particular, parents who engage in conflict can prevent the damaging effects of that conflict by making the conflict less overt, explaining to children the reasons for the conflict, and providing children with some assurance that a secure parent-child and interparental relationship is still present, despite the conflict. digital.library.unt.edu/ark:/67531/metadc283822/
Mutual Influences in Romantic Attachment, Religious Coping, and Marital Adjustment
This study examined associations among romantic attachment anxiety and avoidance, positive and negative religious coping, and marital adjustment in a community sample of 81 heterosexual couples. Both spouses completed the Experiences in Close Relationships Scale (ECR), a brief measure of religious coping (Brief RCOPE), the Dyadic Adjustment Scale (DAS), and a demographic questionnaire as part of a larger study. Multilevel modeling (MLM) for the actor-partner interdependence model (APIM) was used. Attachment avoidance was inversely related to positive religious coping. In contrast, attachment anxiety was directly related to negative religious coping. Positive religious coping buffered the relationship between attachment avoidance and marital adjustment. In contrast, attachment anxiety was detrimental to marital adjustment regardless of positive religious coping, and positive religious coping was related to higher marital adjustment only in the context of low attachment anxiety. Surprisingly, the spouse's attachment anxiety was inversely related to the respondent's marital adjustment only when the respondent reported low levels of negative religious coping, whereas in the context of high negative religious coping, the partner's attachment anxiety was related to higher marital adjustment. Results support using attachment theory to conceptualize religious coping and the consideration of both attachment and religious coping constructs in counseling. digital.library.unt.edu/ark:/67531/metadc283784/
Synthesis and Design of Microwave Filters and Duplexers with Single and Dual Band Responses
In this thesis the general Chebyshev filter synthesis procedure to generate transfer and reflection polynomials and coupling matrices were described. Key concepts such as coupled resonators, non-resonant nodes have been included. This is followed by microwave duplexer synthesis. Next, a technique to design dual band filter has been described including ways to achieve desired return loss and rejection levels at specific bands by manipulating the stopbands and transmission zeros. The concept of dual band filter synthesis has been applied on the synthesis of microwave duplexer to propose a method to synthesize dual band duplexers. Finally a numerical procedure using Cauchy method has been described to estimate the filter and duplexer polynomials from measured responses. The concepts in this thesis can be used to make microwave filters and duplexers more compact, efficient and cost effective. digital.library.unt.edu/ark:/67531/metadc283787/
An Examination of Resnick's Model of Malingering: a Pai Study of Feigned Ptsd
Malingered posttraumatic stress disorder (PTSD) poses a formidable clinical challenge in personal injury and disability cases because of the apparent ease in feigning PTSD and the supposed link (proximate cause) to the claimed damages. The effective assessment of feigned PTSD is particularly challenging because this diagnosis is both easier to fake than other Axis I disorders and more difficult to detect. As an additional confound, some patients with genuine PTSD produce highly variable, elevated profiles on multiscale inventories that are difficult to distinguish from feigned PTSD. The current study examined whether the Personality Assessment Inventory (PAI) can effectively differentiate between genuine and feigned PTSD in 109 inpatients from a trauma unit. The two most effective scales were the MAL and the NDS scales. As a primary focus, the current study was the first empirical investigation of Resnick's model of malingered PTSD that is comprised of three subtypes: pure malingering (pure-M), partial malingering (partial-M), and false imputation (false-I). The primary goal was to evaluate whether each feigning group was able to (a) effectively simulate PTSD symptoms and diagnoses and (b) avoid being classified as feigning. The partial-M group proved to be the best feigning group in achieving these two goals. Furthermore, the use of well-defined groups, including an indeterminate band (i.e., unclassified) around each cut score, was explored. Overall, the use of well-defined groups improved accuracy in classification and reduced the number of false-positives. digital.library.unt.edu/ark:/67531/metadc283796/
Preschool Teachers' Self-reported Levels of Preparation for Classroom Behavior Management
Research indicates that serious behavior problems begin during the early childhood years. The study examined the perceived preparedness of teachers related to behavior management as well as preschool teachers' usage of evidence-based prevention and intervention strategies. The data indicates that preschool teachers feel prepared for managing aggression in their classrooms and report utilizing evidence-based prevention and intervention strategies regularly. Additionally, the data shows a weak relationship between teacher variables and the likelihood of feeling prepared for managing aggression or utilizing evidence-based strategies. The results can be used to gain a better understanding of special education preschool teachers' training needs in regard to behavior management and managing behavior problems in the preschool classroom. digital.library.unt.edu/ark:/67531/metadc283797/
An Investigation of Malingering and Defensiveness Using the Spanish Pai Among Spanish-speaking Hispanic American Outpatients
For response styles, malingering describes the deliberate production of feigned symptoms by persons seeking external gain such as financial compensation, exemption from duty, or leniency from the criminal justice system. In contradistinction, defensiveness occurs when patients attempt to downplay their symptoms of psychological impairment. Both of the aforementioned response styles can markedly affect the accuracy of diagnosis, especially on self-reports, such as multiscale inventories. As an important oversight, no studies have been conducted to examine the effect of culturally specific response styles on profile validity and the classification of malingering among Hispanic American clinical populations. The current study investigated whether the Spanish Personality Assessment Inventory (PAI) effectively distinguished between Spanish-speaking outpatient groups randomly assigned to honest, feigning, and defensive experimental conditions. In examining the results, PAI malingering indicators utilizing Rare Symptoms strategies (NIM and MAL) demonstrated moderate to large effect sizes. For defensiveness, Spanish PAI indicators also demonstrated moderate to very large effect sizes (M d = 1.27; range from 0.94 to 1.68). Regarding psychometric properties, Spanish PAI validity scales, provide adequate to good data on reliability and discriminant validity. Clinical utility of the Spanish PAI increases as different cut scores are employed. digital.library.unt.edu/ark:/67531/metadc283782/
A Performance Guide to Arvo Pärt's Concerto Piccolo Über B-A-C-H for Trumpet, Strings, Harpsichord, and Piano
Arvo Pärt's Concerto Piccolo über B-A-C-H for trumpet, strings, harpsichord, and piano is a brief yet challenging work in the trumpet repertoire. A carefully articulated performance guide is necessary to aid trumpeters in overcoming the numerous musical challenges presented in this piece. Currently, there is no resource that helps in solving performance choices and difficulties in this work. This first section of this document provides historical and contextual information on Arvo Pärt, his compositional output during his experimental period, and subsequently, Concerto Piccolo. The second section includes a performance analysis of the work, while the third gives trumpet players pedagogical suggestions and practical exercises for proper preparation of Concerto Piccolo. This guide presents performers with relevant background, analytical, and pedagogical information required for an informed and high-level performance. digital.library.unt.edu/ark:/67531/metadc283781/
Accuracy and Interpretability Testing of Text Mining Methods
Extracting meaningful information from large collections of text data is problematic because of the sheer size of the database. However, automated analytic methods capable of processing such data have emerged. These methods, collectively called text mining first began to appear in 1988. A number of additional text mining methods quickly developed in independent research silos with each based on unique mathematical algorithms. How good each of these methods are at analyzing text is unclear. Method development typically evolves from some research silo centric requirement with the success of the method measured by a custom requirement-based metric. Results of the new method are then compared to another method that was similarly developed. The proposed research introduces an experimentally designed testing method to text mining that eliminates research silo bias and simultaneously evaluates methods from all of the major context-region text mining method families. The proposed research method follows a random block factorial design with two treatments consisting of three and five levels (RBF-35) with repeated measures. Contribution of the research is threefold. First, the users perceived a difference in the effectiveness of the various methods. Second, while still not clear, there are characteristics with in the text collection that affect the algorithms ability to extract meaningful results. Third, this research develops an experimental design process for testing the algorithms that is adaptable into other areas of software development and algorithm testing. This design eliminates the bias based practices historically employed by algorithm developers. digital.library.unt.edu/ark:/67531/metadc283791/
Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp
Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were determined utilizing a 14-day continuous flow-through study. Samples were analyzed using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) running in positive ion mode. Kinetic BCF was estimated at 0.538, while proportional BCF was estimated at 0.485. Kinetic BCF for the amiodarone study was estimated at 23.033, whereas proportional BCF was estimated at 41.340. Possible contamination of the C18 column and peristaltic pump failure may have impacted uptake results. In light of variability and current lack of research in the field, this work should be considered exploratory rather than conclusive. digital.library.unt.edu/ark:/67531/metadc283798/
Correlates Between Adult Romantic Attachment Patterns and Dimensional Personality Pathology
Previous research has suggested that adult attachment disturbance is related to maladaptic interaction patterns and personality disorder constructs. Specifically, research indicates that those with attachment disturbance are significantly more likely to meet criteria for a number of personality disorders, including borderline personality disorder, narcissistic personality disorder, and antisocial personality disorder. The purpose of this study was to investigate the associations between adult attachment and the new dimensional model of personality disorders scheduled to be released in the Diagnostic and Statistical Manual for Mental Health Diosrders (5th ed.) in spring 2013. Participants completed the Schedule for Adaptive and Nonadaptive Personality (SNAP) to measure dimensional personality functioning and the Experiences in Close Relationships (ECR-R) and the Attachment Prototypes to measure adult attachment patterns. Additionally, select scales from the Personality Assessment Inventory (PAI) and the Five Factor Model (FFM) will be utilized as secondary measures of personality patterns. The results suggest strong associations between adult attachment orientations and specific maladaptive personality characteristics. digital.library.unt.edu/ark:/67531/metadc283794/
Transition Metal Mediated C-o Bond Cleavage: From Co2 Activation to Lignin Degradation
CO2 activation and conversion mediated by transition metal (TM) catalysts were investigated. Homogeneous catalysis of the reverse water gas shift reaction CO2+H2→H2O+CO was studied as a means to reduce CO2.  β-diketiminato metal models L'MI ( L' =C3N2H5-; M = first-row TMs) were considered as potential catalysts. The thermodynamics of prototypical reaction pathways were simulated using B3LYP/aug-cc-pVTZ. Results show that middle series metal complexes result in more thermodynamically favorable properties; therefore, more detailed thermodynamic and kinetic studies were carried out for Mn, Fe, and Co complexes. On the other hand, heterogeneous catalysis of the reduction of CO2 to CO was carried out on Fe, Co, Ni, and Cu surfaces, using the PBE functional. Reaction barriers were calculated using the climbing image nudged elastic band method. Late 3d and 4d transition metal ion (Fe, Co, Ni, Cu, Ru, Rh, Pd, and Ag) mediated activation of dimethyl ether was studied to investigate the intrinsic catalytic properties of metals for C-O bond cleavage. A set of density functional theory (DFT) methods (BLYP, B3LYP, M06, M06-L, B97-1, B97-D, TPSS, and PBE) with aug-cc-pVTZ basis sets was calibrated with CCSD(T)/CBS calculations on reaction energies and barriers. digital.library.unt.edu/ark:/67531/metadc283790/
The Masculinity Masquerade: the Portrayal of Men in Modern Advertising
The depiction of gender in advertising is a topic of continuous discussion and research. The present study adds to past findings with an updated look at how men are represented in U.S. advertising media and the real effects these portrayals have on the male population under the theoretical framework of hegemony and social cognitive theory. This research is triangulated with a textual analysis of the ads found in the March 2013 editions of four popular print publications and three focus group sessions separated by sex (two all-male, one all-female), each of which is composed of a racially diverse group of undergraduate journalism and communications students from a large Southwestern university. The results of the textual analysis reveal little ethnic or physical diversity among male figures in advertising and distinguish six main profiles of masculinity, the most frequent of which is described as the "sophisticated man." The focus groups identify depictions of extreme muscularity and stereotypical male incompetence as the most negative representations, while humorous and hyperbolic portrayals of sexual prowess and hyper-masculinity are viewed positively as effective means of marketing to men. digital.library.unt.edu/ark:/67531/metadc283789/
Deconstructing Webern's Op 25, Drei Lieder: a Multidimensional Assessment
Webern scholarship has not comprehensively examined op. 25, drei lieder. If the selection of text for op. 25 is viewed as one work in three movements they create a ternary form (A-B-A1). To show how this form is developed in the music the author creates a new analytical system based on Schoenberg's Grundgestalt which is defined by three basic ideas: symmetry, liquidation, and variation. The relationship between the voice and accompaniment and Webern's deliberate manipulation of the text is used to reveal the use of a program which is then tied to the numerical symbolism of 2 and 3. digital.library.unt.edu/ark:/67531/metadc283780/
Mechanics and Mechanisms of Creep and Ductile Fracture
The main aim of this dissertation is to relate measurable and hopefully controllable features of a material's microstructure to its observed failure modes to provide a basis for designing better materials. The understanding of creep in materials used at high temperatures is of prime engineering importance. Single crystal Ni-based superalloys used in turbine aerofoils of jet engines are exposed to long dwell times at very high temperatures. In contrast to current theories, creep tests on Ni-based superalloy specimens have shown size dependent creep response termed as the thickness debit effect. To investigate the mechanism of the thickness debit effect, isothermal creep tests were performed on uncoated Ni-based single crystal superalloy sheet specimens with two thicknesses and under two test conditions: a low temperature high stress condition and a high temperature low stress condition. At the high temperature, surface oxidation induced microstructural changes near the free surface forming a layered microstructure. Finite element calculations showed that this layered microstructure gave rise to local changes in the stress state. The specimens also contained nonuniform distribution of initial voids formed during the solidification and homogenization processes. The experiments showed that porosity evolution could play a significant role in the thickness debit effect. This motivated a basic mechanics study of porosity evolution in single crystals subjected to creep for a range of stress states. The study was performed using three-dimensional finite deformation finite element analysis of unit cells containing a single initially spherical void in a single crystal matrix. The materials are characterized by a rate-dependent crystal plasticity constitutive relation accounting for both primary and secondary creep. The effect of initial void spacing and creep exponent was also explored. Based on the experimental observations and results of finite element calculations a quantitative mechanistic model is proposed that can account for both bulk and surface damage effects and assess their relative roles in the observed thickness debit effect. Another set of calculations aim at relating the crack growth resistance and fracture surface morphology to material microstructure for ductile structural metals. The process that governs the ductile fracture of structural materials at room temperature is one of nucleation, growth and coalescence of micron scale voids, and involves large plastic deformations. Experimental studies have shown that fracture surfaces in a wide variety of materials and under a wide variety of loading conditions have remarkable scaling properties. For thirty years, the hope to relate the statistical characterization of fracture surfaces to a measure of a material's crack growth resistance has remained unfulfilled. Only recently has the capability been developed to calculate sufficient amounts of three dimensional ductile crack growth in heterogeneous microstructures to obtain a statistical characterization of the predicted fracture surfaces. This development has enabled the exploration of the relation of both fracture toughness and fracture surface statistics to material properties and microstructure when the fracture mechanism is one of void nucleation, growth and coalescence. The relation of both toughness and the statistical properties of fracture surfaces in calculations of heterogeneous microstructures to various microstructural features is discussed and a remarkable correlation between fracture surface roughness and fracture toughness is shown for the first time. digital.library.unt.edu/ark:/67531/metadc283799/
The Phantom Menace: the F-4 in Air Combat in Vietnam
The F-4 Phantom II was the United States' primary air superiority fighter aircraft during the Vietnam War. This airplane epitomized American airpower doctrine during the early Cold War, which diminished the role of air-to-air combat and the air superiority mission. As a result, the F-4 struggled against the Soviet MiG fighters used by the North Vietnamese Air Force. By the end of the Rolling Thunder bombing campaign in 1968, the Phantom traded kills with MiGs at a nearly one-to-one ratio, the worst air combat performance in American history. The aircraft also regularly failed to protect American bombing formations from MiG attacks. A bombing halt from 1968 to 1972 provided a chance for American planners to evaluate their performance and make changes. The Navy began training pilots specifically for air combat, creating the Navy Fighter Weapons School known as "Top Gun" for this purpose. The Air Force instead focused on technological innovation and upgrades to their equipment. The resumption of bombing and air combat in the 1972 Linebacker campaigns proved that the Navy's training practices were effective, while the Air Force's technology changes were not, with kill ratios becoming worse. However, the last three months of the campaign introduced an American ground radar system that proved more effective than Top Gun in improving air-to-air combat performance. By the end of the Vietnam War, the Air Force and Navy overcame the inherent problems with the Phantom, which were mostly of their own making. digital.library.unt.edu/ark:/67531/metadc283785/
Programming for the Latino Youth: a Content Analysis of Prime Time Television Programs By Three Spanish-language Broadcast Networks
This study reviews U.S. Spanish-language broadcast networks' prime time programming content targeted to the Latino youth audience. It explores the relationship between the Latino youth and prime time programming by Spanish-language broadcast networks and how they seek to attract this market as is reflected in the characteristics and quantity of their content and preferred formats by using the strategic management theory. This study identifies the amount and type of prime time programming that was catered to the Latino youth audience between 2003 and 2012 by the three major Spanish-language networks: Univision, Telemundo, and Telefutura. An observed pattern reveals that prime time programming targeting Latino teenagers is relatively smaller and older in comparison to programming delivered through the general programming. digital.library.unt.edu/ark:/67531/metadc283795/
Shared Norms, Hierarchical Maintenance, and International Hierarchy
The dissertation studies two aspects of international hierarchy. The world of international politics is not one of completely sovereign states competing in anarchy. Patterns of hierarchy, where a dominant state has legitimate control over some actions of a subordinate state, color the globe. First, I look at shared norms and hierarchy. Most studies concerning hierarchy focus on material maximization as an explanation for hierarchy--if hierarchy increases the wealth and security of two states, then hierarchy is more likely. I argue that shared norms held by two states facilitate hierarchy. Shared norms produce a common in-group community, generate common interests, create common ways of doing business, and give rise to common values that increase subordinate states' ability to persuade the dominant state. These factors ease the creation and maintenance of international hierarchical relationships. Second, I study interstate behaviors that can be explained as actions of maintenance by dominant states over subordinates to preserve or increase a level of hierarchy. I theorize that sticks and carrots from a dominant state (like economic sanctions, military interventions, and foreign aid) help sustain a dominant state's rule by convincing subordinate states to follow the dominant state's commands and expectations. Using data on U.S. hierarchies from 1950 to 2010, I utilize multivariate regressions to test hypotheses drawn from these theories. I find that shared norms associate with hierarchy, and maintenance actions uncommonly associate with compliance. digital.library.unt.edu/ark:/67531/metadc283783/
Alchemies
This thesis consists of a collection of poems and a critical preface. The preface is a discussion of Elizabeth Bishop's descriptive mode, as demonstrated by three of her poems: "Sandpiper," "The Monument," and "Santarém." I argue for Bishop's descriptions as creative acts, and examine the gestures that help her make the reader aware of the shaping power she exercises. digital.library.unt.edu/ark:/67531/metadc283793/
Manipulating Sucrose Proton Symporters to Understand Phloem Loading
Phloem vascular tissues transport sugars synthesized by photosynthesis in mature leaves by a process called phloem loading in source tissues and unloading in sink tissues. Phloem loading in source leaves is catalyzed by Suc/H+ symporters (SUTs) which are energized by proton motive force. In Arabidopsis the principal and perhaps exclusive SUT catalyzing phloem loading is AtSUC2. In mutant plants harboring a T-DNA insertion in each of the functional SUT-family members, only Atsuc2 mutants demonstrate overtly debilitated phloem transport. Analysis of a mutant allele (Atsuc2-4) of AtSUC2 with a T-DNA insertion in the second intron showed severely stunted phenotype similar to previously analyzed Atsuc2 null alleles. However unlike previous alleles Atsuc2-4 produced viable seeds. Analysis of phloem specific promoters showed that promoter expression was regulated by Suc concentration. Unlike AtSUC2p, heterologous promoter CoYMVp was not repressed under high Suc conc. Further analysis was conducted using CoYMVp to test the capacity of diverse clades in SUT-gene family for transferring Suc in planta in Atsuc2 - / - mutant background. AtSUC1 and ZmSUT1 from maize complemented Atsuc2 mutant plants to the highest level compared to all other transporters. Over-expression of the above SUTs in phloem showed enhanced Suc loading and transport, but against expectations, plants were stunted. The implications of SUT over-expression to enhance phloem transport and loading are discussed and how it induces a perception of phosphate imbalance is presented. digital.library.unt.edu/ark:/67531/metadc283792/
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/
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/
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/
Central Office Administrators' Perceptions of the Professional Learning Community Process
This study provides a qualitative interpretation of the work done by central office administrators in a school district in Texas as they supported and built capacity for the professional learning community (PLC) process over a five year time period. Literature by PLC scholars, especially R. DuFour, R.B. DuFour, Eaker, Hord, Hipp, Huffman, and Olivier, informed development of the study. In a school district of 19,000 students and 2,000 staff members, ten central office administrators were interviewed to gain their perceptions of their roles in the PLC process. Interviews were analyzed through the processes of initial, focused, and theoretical coding. Documents were examined and used as supplemental sources of data to corroborate the perspectives provided. Findings revealed the story of central office administrators who worked interdependently to support and build capacity in the implementation and sustainment of the PLC process. A thick description of the work based on their perceptions offers actions and behaviors of administrators specific to their roles and practices and protocols developed to hold the work together. A grounded theory was developed with regard to central office administrators' support and capacity-building for the PLC process. From the administrators' perceptions, six theoretical categories relating to central office support and capacity building of the PLC process emerged: 1) establishment, 2) deployment, 3) accountability for implementation, 4) adult learning, 5) collaboration, and 6) leadership development. The study contributes an interpretivist description of the involvement of central office in the PLC process and confirms the importance of the change process in the implementation of the PLC framework. digital.library.unt.edu/ark:/67531/metadc283851/
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/
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