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  Partner: UNT Libraries
 Decade: 2010-2019
 Language: English
 Collection: UNT Theses and Dissertations
9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress
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The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head blight (FHB) disease in wheat and other small grain crops. Loss of LOX1 and LOX5 function resulted in enhanced resistance to F. graminearum infection. Similarly in wheat, RNA interference mediated silencing of the 9-LOX homolog TaLpx1, resulted in enhanced resistance to F. graminearum. Experiments in Arabidopsis indicate that 9-LOXs promote susceptibility to this fungus by suppressing the activation of salicylic acid-mediated defense responses that are important for basal resistance to this fungus. the lox1 and lox5 mutants were also compromised for systemic acquired resistance (SAR), an inducible defense mechanism that is systemically activated throughout a plant in response to a localized infection. the lox1 and lox5 mutants exhibited reduced cell death and delayed hypersensitive response when challenged with an avirulent strain of the bacterial pathogen Pseudomonas syringae pv tomato. LOX1 and LOX5 functions were further required for the synthesis as well as perception of a SAR-inducing activity present in petiole exudates collected from wild-type avirulent pathogen-challenged leaves. Taken together, results presented here demonstrate that 9-LOX contribute to host susceptibility as well as defense against different biotic stressors. digital.library.unt.edu/ark:/67531/metadc115127/
161 Glass: Site Specific Music in an Artistic Context
The composition 161 Glass is a 17-minute musical work with percussion, wind and brass instruments in which the intersection of mid-century architecture, and the art and culture of a dynamic city are inextricably linked. Through this paper, I explore the process of composing a musical work in relationship to the significance of site specific context. The paper begins by defining the concept of site specific art works; then reviews the discourse of the intersection of art, music and architecture. I then delve into the cultural and geographic context surrounding this project from the modern era through the present, and how those perspectives apply to the building and my piece. I reveal how the composition relates the musical ideas to the site. Finally, I describe the collaborative process between myself, the musicians and the Dallas Contemporary staff. digital.library.unt.edu/ark:/67531/metadc28472/
A 018μm Cmos Transmitter for Ecg Signals
Electrocardiography (ECG) signal transmitter is the device used to transmit the electrical signals of the heart to the remote machine. These electrical signals are ECG signals caused due to electrical activities in the heart. ECG signals have very low amplitude and frequency; hence amplification of the signals is needed to strengthen the signal. Conversion of the amplified signal into digital information and transmitting that information without losing any data is the key. This information is further used in monitoring the heart. digital.library.unt.edu/ark:/67531/metadc407805/
The 1896 Vienna Tonkünstler-verein Competition: the Three Award-winning Works and Seven Anonymous Submissions with Clarinet
The Vienna Tonkünstler-Verein (1885-1929) was established for the sole purpose of providing extensive support to the music and musicians of Vienna. The society became renowned in Vienna for its outstanding performances of chamber music and counted among its members many of the city’s foremost musicians and composers. Johannes Brahms had a significant influence on the society as its honorary president and assisted in establishing its composition competitions, aimed at promoting and reviving under-developed chamber genres. Of particular interest to clarinetists is the Verein’s competition of 1896, which aspired to promote chamber music literature for wind instruments. Brahms’s recently completed chamber works for clarinet were clearly influential in fin-de-siècle Vienna; for of the twelve works chosen as finalists in the competition, ten included the clarinet in the chamber combination.The purpose of this document is to provide an English-language history of the Vienna Tonkünstler-Verein and a thorough account of its1896 competition based on my study of the society’s annual reports. In addition, this document will provide the first published account of the anonymous submissions for the 1896 competition. It is my hope that this paper will serve as a springboard for future endeavors aimed at uncovering the identities of the anonymous finalists for this competition. digital.library.unt.edu/ark:/67531/metadc699919/
3D Reconstruction Using Lidar and Visual Images
In this research, multi-perspective image registration using LiDAR and visual images was considered. 2D-3D image registration is a difficult task because it requires the extraction of different semantic features from each modality. This problem is solved in three parts. The first step involves detection and extraction of common features from each of the data sets. The second step consists of associating the common features between two different modalities. Traditional methods use lines or orthogonal corners as common features. The third step consists of building the projection matrix. Many existing methods use global positing system (GPS) or inertial navigation system (INS) for an initial estimate of the camera pose. However, the approach discussed herein does not use GPS, INS, or any such devices for initial estimate; hence the model can be used in places like the lunar surface or Mars where GPS or INS are not available. A variation of the method is also described, which does not require strong features from both images but rather uses intensity gradients in the image. This can be useful when one image does not have strong features (such as lines) or there are too many extraneous features. digital.library.unt.edu/ark:/67531/metadc177193/
3GPP Long Term Evolution LTE Scheduling
Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number of UEs attached to the eNodeB. To evaluate the proposed scheduler algorithm, we assumed two different scenarios based on a number of UEs. When the number of UE is lower than the number of PRBs, the UEs with highest Channel Quality Indicator (CQI) will be assigned PRBs. Otherwise, the scheduler will assign PRBs based on a given proportional fairness metric. The eNodeB’s throughput is increased when the proposed algorithm was implemented. digital.library.unt.edu/ark:/67531/metadc490046/
Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation
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In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empirical dispersion corrections, as well as some lower-level ab initio methods. Basis set convergence is found to be relatively slow due to internal C-H…O and C-H…N contacts. Absent dispersion corrections, many DFT functionals will transpose the two lowest conformers. Dispersion corrections resolve the problem for most functionals. Double hybrids yield particularly good performance, as does MP2.5. In the second project, we propose a simple DFT-based diagnostic for nondynamical correlation effects. Aλ= (1-TAE [ΧλC]/TAE[XC])/λ where TAE is the total atomization energy, XC the “pure” DFT exchange-correlation functional, and ΧλC the corresponding hybrid with 100λ% HF-type exchange. The diagnostic is a good predictor for sensitivity of energetics to the level of theory, unlike most of the wavefunction-based diagnostics. For GGA functionals, Aλ values approaching unity indicate severe non-dynamical correlation. The diagnostic is only weakly sensitive to the basis set (beyond polarized double zeta) and can be applied to problems beyond practical reach of wavefunction ab-initio methods required for other diagnostics. digital.library.unt.edu/ark:/67531/metadc500195/
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/
Absorptive Capacity: An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities
The field of strategic management addresses challenges that firms encounter in an attempt to remain competitive. The ability to explain variation in firm success through examination of knowledge flows has become a prominent focus of research in the strategic management literature. Specifically, researchers have sought to further examine how firms convert knowledge, a phenomenon conceptualized as absorptive capacity. Absorptive capacity is the firm’s ability to acquire, assimilate, transform, and exploit knowledge. Few studies have captured the richness and multi-dimensionality of absorptive capacity, and it remains to be understood how the dimensions of the phenomenon convert knowledge. Furthermore, how absorptive capacity influences the firm remains to be understood. To address these research gaps, this dissertation seeks to (1) determine how absorptive capacity converts knowledge, and (2) determine how absorptive capacity influences firm capabilities. The research questions are investigated using structural modeling techniques to analyze data collected from software-industry firms. The findings offer contributions to the absorptive capacity and capability literatures. For example, absorptive capacity is hypothesized to consist of complex relationships among its internal dimensions. However, findings of this study suggest the relationships among the dimensions are linear in nature. This finding is in line with the theoretical foundations of and early literature on absorptive capacity but contrary to recent conceptualizations, which suggests relationships among the dimensions are more closely related to the theoretical origins of absorptive capacity. Additionally, to examine how absorptive capacity influences the firm, a capability-based perspective is used to hypothesize the influence of absorptive capacity on firm capabilities. Findings suggest absorptive capacity positively influences each dimension of firm capabilities (e.g., operational, customer, and innovation capabilities); thus, absorptive capacity influences the firm by altering firm capabilities. Given the richness of the findings, numerous fields are likely to benefit from this investigation. Through an examination of absorptive capacity and capabilities, this study contributes to the understanding of the absorptive capacity phenomenon and offers insight into how the phenomenon influences the firm. Furthermore, practical implications are offered for managers interested in enhancing firm competitiveness. digital.library.unt.edu/ark:/67531/metadc115064/
Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?
There were two main purposes of this quantitative study. The first purpose was to identify characteristics associated with the selected sample of academic advisors that comprise study. Secondly, the study sought to determine how well work related activities of a selected population of academic advisors correlate with professional characteristics constructs and professional standards constructs of academic advising as a profession. The study used Habley’s (1986) characteristics of a profession to derive the studies professional characteristic construct, education activities, research activities, and professional development activities as it relates to a selected group of academic advisors work related activities. The studies professional standards construct was derived from five Council for the Advancement of Standards (CAS) professional standards for academic as it relates to a selected group of academic advisors work related activities. The study of 78 out of 210 identified full-time academic advisors at two-and four-year public colleges and universities in the North Texas Region utilized a multidimensional researcher-developed Web survey instrument designed to measure professional standards and characteristic within the field of academic advising. Study results reinforced current criticism of research and education activities within the field of academic advising showing that the lack of scholarly research and education activities among academic advisors decreases significantly their efforts towards professionalization. Also, professional standards construct results suggest that the utilization of CAS standards for academic advising as an evaluation tool may enhance an academic advisor’s knowledge of professional standards within the field. digital.library.unt.edu/ark:/67531/metadc500023/
The Academic and Athletic Experiences of African-american Males in a Division I (Fbs) Football Program
This study investigated the academic and athletic experiences of African-American males in a Division I football bowl subdivision football program. Critical race theory, identity development model, and social learning model were the theoretical frameworks used as the critical lenses in a qualitative design to examine the participants. The participants’ responses were analyzed and interpreted using thematic analysis. A qualitative research design, which included individual interviews with 10 second year African-American male football players, was used to address this research problem. The goal was to bring together both the psychological and sociological perspectives and to challenge participants to candidly describe their academic and athletic experiences and attitudes toward obtaining an undergraduate degree. Four themes were determined in the data analysis: differential treatment and determining oneself, time management, relationships, and career aspirations. In relation to the theoretical frameworks, the development of self-confidence and knowledge of balancing their academic and athletic schedules was critical for all participants. The sense of feeling different and challenged because of the differences in culture and experience was evident. From this study, university and collegiate athletics administrators may better understand the backgrounds, challenges, and learning needs of this population. As a result, higher education personnel may improve the services they provide these young men in hopes of educating and developing whole persons—physically, emotionally, intellectually, socially, and spiritually—to become well-rounded and functional in contemporary society. digital.library.unt.edu/ark:/67531/metadc407844/
Academic Reading Online: Digital Reading Strategies of Graduate-level English Language Learners
English language learners (ELLs) face many linguistic and cultural challenges in their attempts to succeed academically. They encounter complex academic text, which is increasingly presented online. Although some research has addressed the challenges that university-level ELLs face when reading online texts, almost all of this prior work has focused on undergraduates. The purpose of the current study was to investigate the reading strategies employed by graduate-level ELLs when reading an academic English text online. Participating in the study were four foreign-born doctoral students from different first-language backgrounds—Arabic, Korean, Urdu, and Vietnamese—and the focus was on commonalities as well as differences among them. All four were enrolled in the same doctoral-level course, which included the reading of a specific online academic article as a course requirement. When reading this text individually, each student participated in a think-aloud procedure, followed by post-reading and discourse-based interviews. Analyses included unitizing data from the think-aloud protocols, coding units for strategies employed, and considering related interview commentary and classroom contributions. In their reading, these students made major use of problem-solving strategies, especially reading segments aloud and questioning. They also employed evaluative strategies as well as metacognitive strategies, which included affirming their understanding or indicating lack of understanding. With respect to global strategies, all made use of the article’s abstract and used the cursor to scroll forward to preview the article. In contrast to previous research with undergraduates, these students made little use of support strategies that involved translation websites. Instead, their major support strategies were navigating to web-based tools, particularly online encyclopedias in English. Despite prior theory and research suggesting the importance of sociorhetorical strategies in academic reading, only one student directed much attention to the authors of the article and to authorial intent. Although all four participants were students in the same doctoral course and were reading the same contextualized article, their strategy use differed in ways that seemed to be related to their educational and cultural backgrounds. Through its detailed analyses of these acts of academic reading, the study contributes to research into the sociocultural nature of ELL students’ reading process. digital.library.unt.edu/ark:/67531/metadc801951/
Academic Self-efficacy of Adult First-generation Students Enrolled in Online Undergraduate Courses
This study examined differences between adult first-generation (AFG) and adult-continuing generation (ACG) students’ academic self-efficacy with regard to the online courses in which they were currently enrolled. The study used an online survey methodology to collect self-reported quantitative data from 1,768 undergraduate students enrolled in an online course at a mid-sized, four-year public university in the southwestern United States; 325 cases were usable for the study. The t-tests revealed no statistically significant differences between the academic self-efficacy of the AFG and ACG students. Parents’ level of educational attainment was unrelated to adult students’ academic self-efficacy with online courses. Ordinary least-squares analysis was used to evaluate student characteristics that might be associated with academic self-efficacy in the online environment. A combination of gender, GPA, age, race/ethnicity (White, Black, Hispanic, and other), and number of previous online courses predicted a statistically significant 12% of the variance in academic self-efficacy in an online environment (p < .001). Age (p < .001) and self-efficacy were positively correlated, meaning that adult students reported greater academic self-efficacy than did younger students; and number of previous online courses (p < .001) was also positively correlated to academic self-efficacy, indicating that students with greater experience with online courses reported a greater sense of academic self-efficacy in that environment than students who had completed fewer online courses. This study has implications of providing additional insight for higher education practitioners working with adult learners. Identifying additional factors influencing adult learners’ academic self-efficacy in an online academic environment may be useful when building effective strategies to improve online retention and completion rates for these students. Future research should examine a wider variety of variables beyond demographic characteristics. External and internal factors, along with existing theories of behaviors should be investigated to help explain adult persistence and retention online and in face-to-face courses. digital.library.unt.edu/ark:/67531/metadc700075/
Academic, Social and Emotional Functioning of College Students with Attention Deficit/hyperactivity Disorder (Adhd)
Attention deficit/hyperactivity disorder (ADHD) is frequently associated with negative occupational, social and psychological outcomes among community samples of adults; as such, it is expected that college students with ADHD face similar struggles. The research targeting this group of individuals, however, is sparse and tempered by significant limitations. The current study aimed to address methodological limitations in the current literature by including instruments to formally diagnosis ADHD and comorbid disorders, utilizing psychometrically sound instruments and comparing functioning of college students with ADHD across gender and subtype. It was hypothesized that participants with ADHD would report lower GPAs, higher levels of emotional distress and negative relationship characteristics than participants without ADHD. It was also hypothesized that participants with ADHD-combined type (ADHD-C) would report higher levels of substance and alcohol use than participants with ADHD-predominately inattentive type (ADHD-I), and that participants with ADHD-I would report higher levels of anxiety and depression than participants with ADHD-C. Women diagnosed with ADHD were expected to report higher levels of anxiety and depression than men diagnosed with ADHD; whereas, men diagnosed with ADHD were expected to report higher levels of substance and alcohol use than women. MANOVA, ANOVA and Mann-Whitney U tests were conducted to test hypotheses. Results revealed no significant differences between the ADHD and comparison group on GPA and relationship characteristics. Participants diagnosed with ADHD did report significantly higher emotional distress than participants in the comparison group. No differences in GPA or relationship characteristics were found across ADHD subtype or gender. Overall, these findings provide evidence to suggest that college students with ADHD are functioning relatively well compared to their non-ADHD peers. digital.library.unt.edu/ark:/67531/metadc804887/
The Academic Steroid: Nonmedical Use of Prescription Stimulants at a North Texas University
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The goal of this study was to determine the extent, motivations, and justifications of nonmedical prescription stimulant use among the population at a large public university in the North Texas region. Participants consisted of 526 undergraduate students enrolled at the studied university during the spring and summer 2014 semesters. The findings of the study suggest that the nonmedical use by students was higher than the findings in much of the current literature, but was within the parameters established in the literature. The primary motivation for nonmedical use was academic in nature and was justified by moderation of nonmedical use to strategic academic times. digital.library.unt.edu/ark:/67531/metadc699893/
Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers
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The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide the industry with a better understanding of heat exchanger design and heat exchanger material selection. The worth in this is preventing overdesign and producing more efficient heat exchangers. Furthermore, ASHRAE members and the corrosion community will find value in a defined corrosion system and corrosion test procedure. The information gained through past research has progressed assessment of material performance; however, the methods improperly simulate and expedite natural weathering. The most common method being used is the ASTM (American Society of Testing Materials) Sea Water Acetic Acid Test. The research discussed in this paper was focused on improving a standard corrosion system by implementing system modifications to simulate heat exchanger operation while performing a modified wet-dry cyclic test (e.g. ASTM G85 Annex 5). The goal is to produce results that are more representative of natural corrosion behavior and its forms. Current results were gathered from five of ten samples that underwent initial testing. Finally, possible improvements towards the chamber system and the test method, including the salt solution, are discussed. digital.library.unt.edu/ark:/67531/metadc849775/
Accelerated Degree Program Faculty: Motivation to Teach
Adult educators are a growing part of American higher education. Because of their increasing prominence in adult education, it is essential to understand what roles these educators play and what motivates them to remain in the profession despite poor work prospects and conditions. Research to date, however, focuses primarily on the adult learner and not the adult educator. The purpose of this qualitative, multiple-case study was to explore the role and motivation for teaching of adult educators employed as adjunct faculty in an accelerated degree program at a small, liberal arts college in the northwest United States. Purposeful sampling was used to select the five participants for the study. All participants taught in the program for more than five years and were considered to be successful in their positions by peers, students, and administrators. The study employed a preliminary demographic survey to solicit initial background data on the instructors. Other data collection included in-depth, open-ended, face-to-face interviews, document analysis, and classroom observation. The results showed that all five participants identified the following roles and assumed them in the classroom: (a) facilitator, (b) listener, (c) specialist, (d) guide, (e) adviser, and (f) co-learner or colleague. Further results showed that all five participants were motivated to teach in the program for reasons other than monetary compensation. Although participants shared different levels of personal commitment to the institution, they all expressed extensive commitment to teaching, their discipline, and students. Motivating factors for teaching were (a) opportunity to teach part time, (b) love for the subject, (c) opportunity to gain more expertise in the field, (d) opportunity to grow and learn, (e) opportunity to give back, and (f) student success and growth. A major practical implication of this study is that adjunct faculty in an adult education program are motivated to teach for different reasons, but the primary motivation can be seen as altruistic versus monetary and practical. If college administrators want to produce and retain successful adjunct faculty, they must recruit and hire those individuals whose motivation for teaching is altruistic with a desire to enrich the lives of students. digital.library.unt.edu/ark:/67531/metadc849699/
An Accelerometer-based Gesture Recognition System for a Tactical Communications Application
In modern society, computers are primarily interacted with via keyboards, touch screens, voice recognition, video analysis, and many others. For certain applications, these methods may be the most efficient interface. However, there are applications that we can conceive where a more natural interface could be convenient and connect humans and computers in a more intuitive and natural way. These applications are gesture recognition systems and range from the interpretation of sign language by a computer to virtual reality control. This Thesis proposes a gesture recognition system that primarily uses accelerometers to capture gestures from a tactical communications application. A segmentation algorithm is developed based on the accelerometer energy to segment these gestures from an input sequence. Using signal processing and machine learning techniques, the segments are reduced to mathematical features and classified with support vector machines. Experimental results show that the system achieves an overall gesture recognition accuracy of 98.9%. Additional methods, such as non-gesture recognition/suppression, are also proposed and tested. digital.library.unt.edu/ark:/67531/metadc822779/
Acceptance Theories for Behavior in Conducting Research: Instructors in the Rajabhat University System, Thailand
Responding to globalization and its effects on education and research development, the Thai government decided to push all public universities to become autonomous and establish a system of quality assurances. The establishment of quality assurances has had a large impact on many Thai instructors, especially in new public universities. Thai instructors are now forced to more focus on conducting research because the number of research publications is regarded as one of the main criteria for quality universities. The purpose of this study is to investigate the key factors, at the individual and university levels, which impact on the instructors' behavior in conducting research of the full-time instructors in the faculty of Management Science from the Rajabhat Universities in Thailand. The current study will help explain how and why the instructors accept or refuse to conduct research and provide insight into the salient factors motivating the instructors to produce more research by conducting HLM. Data were collected from 694 participants at 37 institutions via a questionnaire survey. The findings revealed that there was no difference among these 37 universities on behavior in conducting research. The key factors statistically influencing behavior in conducting research of the instructors were facilitating conditions, academic degree, social influence, and usefulness as well as ease of conducting research that the instructors perceived. This study gained 46% of effect size. digital.library.unt.edu/ark:/67531/metadc848155/
Acceptor-sensitizers for Nanostructured Oxide Semiconductor in Excitonic Solar Cells
Organic dyes are examined in photoelectrochemical systems wherein they engage in thermal (rather than photoexcited) electron donation into metal oxide semiconductors. These studies are intended to elucidate fundamental parameters of electron transfer in photoelectrochemical cells. Development of novel methods for the structure/property tuning of electroactive dyes and the preparation of nanostructured semiconductors have also been discovered in the course of the presented work. Acceptor sensitized polymer oxide solar cell devices were assembled and the impact of the acceptor dyes were studied. The optoelectronic tuning of boron-chelated azadipyrromethene dyes has been explored by the substitution of carbon substituents in place of fluoride atoms at boron. Stability of singlet exited state and level of reduction potential of these series of aza-BODIPY coumpounds were studied in order to employ them as electron-accepting sensitizers in solid state dye sensitized solar cells. digital.library.unt.edu/ark:/67531/metadc699927/
Accessing the Power of Aesthetics in Human-computer Interaction
In information systems design there are two schools of thought about what factors are necessary to create a successful information system. The first, conventional view holds that system performance is a key, so that efficiency characteristics such as system usability and task completion time are primary concerns of system designers. The second, emerging view holds that the visual design is also the key, so that visual interface characteristics such as visual appeal, in addition to efficiency characteristics, are critical concerns of designers. This view contends that visual design enhances system use. Thus, this work examines the effects of visual design on computer systems. Visual design exerts its influence on systems through two mechanisms: it evokes affective responses from IT users, such as arousal and pleasure and it influences individuals’ cognitive assessments of systems. Given that both affective and cognitive reactions are significant antecedents of user behaviors in the IT realm, it is no surprise that visual design plays a critical role in information system success. Human-computer-interaction literature indicates that visual aesthetics positively influences such information success factors as usability, online trust, user satisfaction, flow experience, and so on. Although academic research has introduced visual design into the Information Systems (IS) field and validated its effects, visual design is still very limited in three contexts: product aesthetics in e-commerce, mobile applications and commercial emails. This dissertation presents three studies to help fill these theoretical gaps respectively. digital.library.unt.edu/ark:/67531/metadc500128/
Accomplished Teachers' Instructional Decisions About Shakespeare
Teachers' decisions are a powerful influence on student learning and it is important to fully document accomplished teachers' instructional decisions, as well as to investigate possible influences on those decisions. Shakespearean dramas are central to high school curricula across the U.S. and pose particular instructional challenges, therefore teachers' decisions about teaching these texts are of particular interest. There is limited empirical research, however, about these instructional decisions. Thus, the purpose of this study was to describe how four accomplished high school English teachers working on a single campus make instructional decisions about teaching a Shakespearean play. Specifically, research questions addressed teachers' decisions regarding the teaching of a Shakespearean play and various influences on those decisions (self-reports and inferences from the data). Case study methodology was used, including an inductive analysis of individual teacher interviews, classroom observations, focus group, instructional artifacts, and researcher's journal. The findings revealed that instructional activities described by these teachers addressed support for meaning-making during four stages of reading instruction: (a) before, during, and after; (b) before; (c) during; and (d) after. Comparison of these cases suggests that, although each teacher brings personal preferences and unique background knowledge to her instructional decisions, all make decisions to promote student engagement and student construction of meaning. Regarding influences on these teachers' decisions about teaching the Shakespearean play, four categories were identified: (a) response to students; (b) aspects of the text; (c) response to contextual constraints and supports; and (d) personal preferences and background experiences. Individual teacher differences are clearly a strong influence, even among this group of colleagues on the same campus. Also, two influences not reported explicitly by the teachers suggest a complex integration of these influences. One is their intuitive thinking, which deserves a closer investigation in future research. The other proposes that each teacher's decisions are influenced by her instructional interaction working model (IIWM), a conceptual framework that shapes each teacher's conversational patterns, non-verbal behaviors, and other interactional patterns. Further research should explore the use of such a model to describe and explain the complexity of teachers' decisions, particularly when teaching complex, challenging tasks and texts. digital.library.unt.edu/ark:/67531/metadc271873/
Accountability in Schools: a Study of High School Accountability Ratings and College Success
The purpose of this study was to determine the relationship between high school campus accountability ratings, college readiness indicators, and the percent of students who achieved first year college success. Correlation and multiple regression analyses were used to analyze the relationship between the variables. Data was analyzed for two-year and four-year postsecondary educational institutions which were divided by eight school district types. Regression analysis of the relationship between high school campus accountability ratings and the percent of students who achieved first year college success for four- year post secondary educational institutions revealed statistically significant results ranging from R2 =.179 to R2 = .220. Similar results were found for two-year post secondary educational institutions with statistically significant results ranging from R2 = .049 to R2 = .218. The results indicated negligible to small relationships between the variables. Regression results of the analysis for the relationship between college readiness indicators and the percent of students who achieved first year college success revealed statistically significant results for 2 - year post secondary educational institutions ranging from R2 = .077 to R2 = .596 and for 4 -year post secondary educational institutions ranging from R2 = .048 to R2 = .304. These results indicated small to moderate relationships between college readiness indicators and the percent of students who achieve first year college success. digital.library.unt.edu/ark:/67531/metadc283865/
Accreditation Facilitation Projects: Supporting High Quality Early Childhood Education and Care
High-quality early childhood education and care (ECEC) are linked to positive developmental outcomes for children. Systems have been created to define, measure and promote high-quality ECEC. National accreditation status is deemed the gold standard of a high-quality program, yet many centers are unable to achieve this without assistance. With the help of Accreditation Facilitation Projects (AFPs), many low-income centers are able to achieve accreditation. Centers collaborating with an AFP reap many benefits including financial support, ongoing training and mentoring, and guidance through the accreditation process. AFPs invest greatly in the centers they collaborate with and the longer the center takes to achieve accreditation, the more resources an AFP must expend. The purposes of this study were to understand if the educational level of center director, the total enrollment of a center, or the percentage of children receiving government subsidies could predict the time it takes for a center to complete the accreditation process while receiving assistance from an AFP, and to determine if there are differences in attitudes about program accreditation between center directors and early learning specialists who serve as accreditation mentors to the directors. Findings revealed that a) the higher educational level of program directors is associated with a quicker time to program accreditation, b) both the total enrollment of the center and the percentage of children receiving government subsidies do not predict time to accreditation, c) the number of total staff in a center is associated with a quicker time to accreditation, and d) there is no significant difference between the directors' attitudes and early learning specialists' attitudes toward accreditation and accreditation facilitation projects. AFPs looking to streamline their accreditation process and provide accountability to their stakeholders regarding their investments over time can use these findings to choose to collaborate with centers that have directors who have at least a bachelor's degree in order to shorten the time to accreditation. digital.library.unt.edu/ark:/67531/metadc271887/
Acculturation, Acculturative Stress, and Anxiety Among Hispanic Undergraduates
First generation college students face some unique challenges in the pursuit of higher education. Aside from academic stressors, there are stressors related to social and cultural transitions which may exacerbate pre-existing emotional or psychological distress. Research suggests that acculturation influences psychological well-being and development. The current study examined the relationships between acculturation, acculturative stress, socio-economic status, and symptoms of anxiety among first-generation college students of Hispanic origin. Participants (N = 125) included those who were first in their family to attend college and were primarily female, of traditional college age, and of Mexican heritage. All measures were self-report and were completed online. Overall, this study was inconclusive as most analyses were underpowered. The present study failed to support a relationship between style of acculturation and symptoms of anxiety, although, experiencing Anglo marginality was related to high levels of acculturative stress and anxiety. Finally, regression analysis revealed that acculturative stress, age, and Anglo marginalization were significant predictors of anxiety and accounted for 31% of variance in anxiety. Implications of the present study were discussed. Further study with adequate power is highly recommended. digital.library.unt.edu/ark:/67531/metadc68072/
Acculturation and Depression in Older Mexican American Adults: the Role of Social Support
Despite socioeconomic disadvantages, less acculturated Mexican Americans tend to exhibit better mental health than their more acculturated counterparts. However, in the case of older Mexican American adults, research has demonstrated the opposite to be true (Gonzalez, Haan, & Hinton, 2001). A variable of interest potentially responsible for this difference is social support. Thus, the current study proposed to investigate the mediation and moderation effects that social support has on the relationship between acculturation and depression in older Mexican American adults age 60 or older. Data from the Health and Retirement Study (HRS) was analyzed. Results showed that the mediating effect of contact with one’s children (-.109*) and the moderating effect of total social support and contact with one’s children (-.127*; -.103*) were statistically significant in the relationship between acculturation and depression. Although these effects are small they may still hold important implications for better understanding this population. digital.library.unt.edu/ark:/67531/metadc149567/
Acculturation and Feminist Endorsement on Control of Health and Health Behaviors in Hispanic Females
Hispanic women are the fastest growing population in the United States. Thus, it is important to explore health disparities that affect this population and better understand potential causes. Several explanations have been proposed for disparities that exist including turning to cultural alternatives rather than conventional medicine, low numbers of health insurance enrollments among Hispanics, and acculturation. However, little attention has been given to explanations that take into account the unique experiences of Hispanic women. The present study explored these experiences through investigation of endorsement of feminist attitudes (e.g., gender role adherence and beliefs that men and women should be treated equally in society) and level of acculturation. Undergraduate Hispanic women (18-24 years of age, M = 20.25, SD = 1.51) at the University of North Texas completed measures including the Multidimensional Health Questionnaire, the Acculturation Rating Scale for Mexican Americans-II, and the Liberal Feminist Attitude and Ideology Scale. Although results indicate that acculturation was not significant in the sample, feminist endorsement was found to be positively correlated with health-esteem, health-efficacy, and internal-health locus of control. Limitations and recommended directions for future research are explored. digital.library.unt.edu/ark:/67531/metadc500136/
Accuracy and Efficiency in Computational Chemistry: The Correlation Consistent Composite Approach
One of the central concerns of computational chemistry is that of efficiency (i.e. the development of methodologies which will yield increased accuracy of prediction without requiring additional computational resources – RAM, disk space, computing time). Though the equations of quantum mechanics are known, the solutions to these equations often require a great deal of computing power. This dissertation primarily concerns the theme of improved computational efficiency (i.e. the achievement of greater accuracy with reduced computational cost). Improvements in the efficiency of computational chemistry are explored first in terms of the correlation consistent composite approach (ccCA). The ccCA methodology was modified and this enhanced ccCA methodology was tested against the diverse G3/05 set of 454 energetic properties. As computational efficiency improves, molecules of increasing size may be studied and this dissertation explored the issues (differential correlation and size extensivity effects) associated with obtaining chemically accurate (within 1 kcal mol-1) enthalpies of formation for hydrocarbon molecules of escalating size. Two applied projects are also described; these projects concerned the theoretical prediction of a novel rare gas compound, FKrOH, and the mechanism of human glutathione synthetase’s (hGS) negative cooperativity. The final work examined the prospect for the parameterization of the modified embedded atom method (MEAM) potential using first principles calculations of dimer and trimer energies of nickel and carbon systems. This method of parameterization holds promise for increasing the accuracy of simulations for bulk properties within the field of materials science. digital.library.unt.edu/ark:/67531/metadc84300/
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/
Accurate and Reliable Prediction of Energetic and Spectroscopic Properties Via Electronic Structure Methods
Computational chemistry has led to the greater understanding of the molecular world, from the interaction of molecules, to the composition of molecular species and materials. Of the families of computational chemistry approaches available, the main families of electronic structure methods that are capable of accurate and/or reliable predictions of energetic, structural, and spectroscopic properties are ab initio methods and density functional theory (DFT). The focus of this dissertation is to improve the accuracy of predictions and computational efficiency (with respect to memory, disk space, and computer processing time) of some computational chemistry methods, which, in turn, can extend the size of molecule that can be addressed, and, for other methods, DFT, in particular, gain greater insight into which DFT methods are more reliable than others. Much, though not all, of the focus of this dissertation is upon transition metal species – species for which much less method development has been targeted or insight about method performance has been well established. The ab initio approach that has been targeted in this work is the correlation consistent composite approach (ccCA), which has proven to be a robust, ab initio computational method for main group and first row transition metal-containing molecules yielding, on average, accurate thermodynamic properties, i.e., within 1 kcal/mol of experiment for main group species and within 3 kcal/mol of experiment for first row transition metal molecules. In order to make ccCA applicable to systems containing any element from the periodic table, development of the method for second row transition metals and heavier elements, including lower p-block (5p and 6p) elements was pursued. The resulting method, the relativistic pseudopotential variant of ccCA (rp-ccCA), and its application are detailed for second row transition metals and lower p-block elements. Because of the computational cost of ab initio methods, DFT is a popular choice for the study of transition metals. Despite this, the most reliable density functionals for the prediction of energetic properties (e.g. enthalpy of formation, ionization potential, electron affinity, dissociation energy) of transition metal species, have not been clearly identified. The examination of DFT performance for first and second row transition metal thermochemistry (i.e., enthalpies of formation) was conducted and density functionals for the study of these species were identified. And, finally, to address the accuracy of spectroscopic and energetic properties, improvements for a series of density functionals have been established. In both DFT and ab initio methods, the harmonic approximation is typically employed. This neglect of anharmonic effects, such as those related to vibrational properties (e.g. zero-point vibrational energies, thermal contributions to enthalpy and entropy) of molecules, generally results in computational predictions that are not in agreement with experiment. To correct for the neglect of anharmonicity, scale factors can be applied to these vibrational properties, resulting in better alignment with experimental observations. Scale factors for DFT in conjunction with both the correlation and polarization consistent basis sets have been developed in this work. digital.library.unt.edu/ark:/67531/metadc500071/
Accurate Energetics Across the Periodic Table Via Quantum Chemistry
Greater understanding and accurate predictions of structural, thermochemical, and spectroscopic properties of chemical compounds is critical for the advancements of not only basic science, but also in applications needed for the growth and health of the U.S. economy. This dissertation includes new ab initio composite approaches to predict accurate energetics of lanthanide-containing compounds including relativistic effects, and optimization of parameters for semi-empirical methods for transition metals. Studies of properties and energetics of chemical compounds through various computational methods are also the focus of this research, including the C-O bond cleavage of dimethyl ether by transition metal ions, the study of thermochemical and structural properties of small silicon containing compounds with the Multi-Reference correlation consistent Composite Approach, the development of a composite method for heavy element systems, spectroscopic of compounds containing noble gases and metals (ArxZn and ArxAg+ where x = 1, 2), and the effects due to Basis Set Superposition Error (BSSE) on these van der Waals complexes. digital.library.unt.edu/ark:/67531/metadc822822/
Across Borders and Barlines: Chicana/o Literature, Jazz Improvisation, and Contrapuntal Solidarity
In this study, I examine Chicana/o writings and Black and Brown musical traditions as they entwine in urban centers and inform local visions of inclusion and models of social change. By analyzing literature and music from South Texas, Southern California, and Northeastern Michigan, I detail how the social particularities of each zone inform Chicana/o cultural productions rooted in the promise of empowerment and the possibility of cross-cultural solidarity. I assert that highlighting localized variations on these themes amplifies contrapuntal solidarities specific to each region, the relationship between different, locally conceived conceptions of Chicana/o identity, and the interplay between Brown and Black aesthetic practices in urban centers near national borders. Through literary critical and ethnomusicological frameworks, I engage the rhetorical patterns that link poetry, jazz improvisation, essays, musical playlists, and corridos to illumine a web of discourses helping to establish the idiosyncratic yet complimentary cultural mores that shape localized social imaginaries in the United States. digital.library.unt.edu/ark:/67531/metadc500033/
Act Like a Punk, Sing Like a Feminist: a Longitudinal Content Analysis of Feminist Themes in Punk Rock Song Lyrics, 1970-2009
Punk rock music has long been labeled sexist as copious media-generated accounts and reports of the genre concentrate on male artists, hyper-masculine performances, and lyrics considered to be aggressive, sexist, and misogynist. However, scholars have rarely examined punk rock music longitudinally, focusing heavily on 1980s and 1990s manifestations of the genre. Furthermore, few systematic content analyses of feminist themes in punk rock song lyrics have been conducted. The present research is a longitudinal content analysis of lyrics of 600 punk rock songs released for four decades between 1970 and 2009 to examine the prevalence of and longitudinal shifts in antiestablishment themes, the prevalence of and longitudinal shifts in sexist themes relative to feminist themes, the prevalence of and longitudinal shifts in specific feminist branches, and what factors are related to feminism. Using top-rated albums retrieved from Sputnik Music’s “Best Punk Albums” charts, systematic random sampling was applied to select 50 songs for each combination of three gender types and four decades. Sexism and feminism were then operationalized to construct a coding sheet to examine relevant dimensions. While the present study found no significant patterns of longitudinal increase or decrease in feminist or sexist themes, it revealed that feminist themes were consistently high across four decades and, furthermore, indicated a phenomenon of post-modern hybridity. digital.library.unt.edu/ark:/67531/metadc801944/
An Action Research Study of Community Building with Elementary Students in a Title I School
“In what ways does teaching with folk arts inspired visual arts-based instruction enhance community building among elementary students in a Title I school?” was the primary research question in this study. Agreeing with past and present day research that the construct of community is vital to social and cultural capital, this research attempts to determine how the notion of community benefits both students and teachers in the elementary art classroom. Folk art was utilized because this genre was accessible in terms of locality and familiarity among students and teachers. The purpose of this investigation was to produce teaching strategies and methods that show how community can be formed in the art classroom. The participants were elementary students, Grades 2 and 3, in a Title I school located in Denton, Texas. This investigation was conducted under an action research methodology. This approach to research is intended to be transformational, emergent, and accommodating. I recorded observations, field notes, and conversations from the participants. Emergent themes were discovered through content analysis and conceptual maps. Results from this investigation concluded transformation is only possible if the person wants change to happen. Data also showed that community and art education are symbiotic. Transformation, growth, and cultivation are demands that must be met in order for this relationship to flourish. In addition, data suggested that the role of folk arts-based lessons played a significant role in building community among second and third graders. digital.library.unt.edu/ark:/67531/metadc500214/
Actions Taken by Texas School Districts to Prevent Fraud
This research is a descriptive analysis answering the question, what measures are currently taken by the leadership&#8213;boards of trustees and superintendents of schools&#8213;of Texas school districts to prevent embezzlement? The research perspective utilized was quantitative with a descriptive, cross-sectional design. Data collection was accomplished through a survey with questions constructed from the most commonly recommended strategies discovered through the review of literature. The survey was distributed to the 1031 superintendents of school districts in Texas via email. The response rate was 33% or 339 returned surveys. The data set created concentrates on the four most common preventive measures: policy and procedure, management, auditing, and ethics. These measures are considered as they function to interrupt the principles of the fraud triangle. Comparisons were completed regarding region, district size, superintendent tenure and superintendent experience. Policy adoption was found to be extremely widespread. Procedures written to fully implement policy were less prevalent. Review of management practices found problems concerning credit cards, personnel evaluations, and password access to multiple computer finance recordkeeping systems concentrated in one employee. External auditing programs were universal due to statutory mandate but internal auditors and internal audit committees were few. Ethics training for business office personnel existed but with little consistent application across districts. The adoption of a code of ethics for business office personnel was rare. Recommendations made were that school leaders should be educated concerning appropriate actions in the common prevention areas. They need an to understand the importance of internal auditing, know the language in local policy, and they need to write procedures. digital.library.unt.edu/ark:/67531/metadc68052/
Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses
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The purpose of this study is to find out that if antibiotic streptomycin decreases neuronal network activity or affects the pharmacological responses. The experiments in this study were conducted via MEA (multi-electrode array) technology which records neuronal activity from devices that have multiple small electrodes, serve as neural interfaces connecting neurons to electronic circuitry. The result of this study shows that streptomycin lowered the spike production of neuronal network, and also, sensitization was seen when neuronal network pre-exposed to streptomycin. digital.library.unt.edu/ark:/67531/metadc700026/
The Acute Hormonal Response to the Kettlebell Swing Exercise
The purpose of this investigation was to examine the acute hormonal response to a bout of kettlebell swing exercise. Ten healthy men (19-30 y, 23.6 ± 3.5 y, 174.6 ± 5.7 cm, 78.7 ± 9.9 kg) who were engaged in resistance training at least twice per week but were inexperienced with kettlebell swings participated in this study. Participants were familiarized with the kettlebell swing exercise during an initial visit. During the subsequent experimental protocol visit, participants performed 12 rounds of 30 seconds of 16-kg kettlebell swings alternated with 30 seconds of rest. Heart rate (HR) and rating of perceived exertion (RPE) were measured at the end of every round of swings. Fasted blood samples were collected pre-exercise (PRE), immediately post (IP), 15 minutes post (P15), and 30 minutes post exercise (P30) and analyzed for total testosterone (T), growth hormone (GH), cortisol, and lactate concentrations. Participants completed a total of 227 ± 23 swings (average swings per round: 19 ± 2). HR and RPE increased significantly (P < 0.05) throughout the exercise protocol. Lactate concentrations were significantly increased at all post exercise time points compared to PRE. T was significantly increased at IP compared to PRE. GH was significantly increased at IP, P15, and P30 compared to PRE. Cortisol was significantly increased at IP and P15 compared to PRE. 12 rounds of 30 seconds of kettlebell swing exercise induced an acute increase in T, GH, and cortisol concentrations in resistance trained men. Additionally, this exercise protocol induced a large increase in HR and lactate concentration. Thus, the kettlebell swing exercise might provide an effective method for simultaneous endurance and resistance training. digital.library.unt.edu/ark:/67531/metadc407736/
The Adagio of Mahler's Ninth Symphony: A Schenkerian Analysis and Examination of the Farewell Story
Mahler's Ninth Symphony, since its premier in 1912, has sparked much debate about its programmatic meaning. This thesis provides an in-depth analysis of the Adagio and an examination of the controversy of the farewell story. In the process of the analysis I have compared my findings to some of the important authors in Mahler's field such as Vera Micznik, Henry-Louis de La Grange, and Christopher Orlo Lewis. Some of the conclusions are that a closer investigation of the music is necessary and that the programmatic reading of the farewell story can be appropriate. digital.library.unt.edu/ark:/67531/metadc68028/
Adapting on the Plains: the United States Army's Evolution of Mobile Warfare in Texas, 1848-1859
The Army, despite having been vexed for a century on how to effectively fight the Plains Indians, ultimately defeated them only a decade after the Civil War. This thesis will bring to the forefront those individuals who adapted fighting techniques and ultimately achieved victories on the Texas frontier before the Civil War. The majority of these victories came as a result of mounted warfare under the direction of lower ranking officers in control of smaller forces. The tactic of fighting Indians from horseback was shown to be effective by the Rangers and later emulated by the Army. digital.library.unt.edu/ark:/67531/metadc271787/
Adaptive Advantages of Carotenoid Pigments in Alpine and Subalpine Copepod Responses to Polycyclic Aromatic Hydrocarbon Induced Phototoxicity
Alpine zooplankton are exposed to a variety of stressors in their natural environment including ultraviolet radiation. Physiological coping mechanisms such as the accumulation of photoprotective compounds provide these zooplankton protection from many of these stressors. Elevated levels of carotenoid compounds such as astaxanthin have been shown to help zooplankton survive longer when exposed to ultraviolet radiation presumably due to the strong antioxidant properties of carotenoid compounds. This antioxidant capacity is important because it may ameliorate natural and anthropogenic stressor-induced oxidative stress. While previous researchers have shown carotenoid compounds impart increased resistance to ultraviolet radiation in populations of zooplankton, little work has focused on the toxicological implications of PAH induced phototoxicity on zooplankton containing high levels of carotenoid compounds. This thesis discusses research studying the role that carotenoid compounds play in reducing PAH induced phototoxicity. By sampling different lakes at elevations ranging from 9,500' to 12,700' in the front range of the Colorado Rocky Mountains, copepod populations containing different levels of carotenoid compounds were obtained. These populations were then challenged with fluoranthene and ultraviolet radiation. Results discussed include differences in survival and levels of lipid peroxidation among populations exhibiting different levels of carotenoid compounds, and the toxicological and ecological implications of these results. digital.library.unt.edu/ark:/67531/metadc28444/
Adaptive Power Management for Autonomic Resource Configuration in Large-scale Computer Systems
In order to run and manage resource-intensive high-performance applications, large-scale computing and storage platforms have been evolving rapidly in various domains in both academia and industry. The energy expenditure consumed to operate and maintain these cloud computing infrastructures is a major factor to influence the overall profit and efficiency for most cloud service providers. Moreover, considering the mitigation of environmental damage from excessive carbon dioxide emission, the amount of power consumed by enterprise-scale data centers should be constrained for protection of the environment.Generally speaking, there exists a trade-off between power consumption and application performance in large-scale computing systems and how to balance these two factors has become an important topic for researchers and engineers in cloud and HPC communities. Therefore, minimizing the power usage while satisfying the Service Level Agreements have become one of the most desirable objectives in cloud computing research and implementation. Since the fundamental feature of the cloud computing platform is hosting workloads with a variety of characteristics in a consolidated and on-demand manner, it is demanding to explore the inherent relationship between power usage and machine configurations. Subsequently, with an understanding of these inherent relationships, researchers are able to develop effective power management policies to optimize productivity by balancing power usage and system performance. In this dissertation, we develop an autonomic power-aware system management framework for large-scale computer systems. We propose a series of techniques including coarse-grain power profiling, VM power modelling, power-aware resource auto-configuration and full-system power usage simulator. These techniques help us to understand the characteristics of power consumption of various system components. Based on these techniques, we are able to test various job scheduling strategies and develop resource management approaches to enhance the systems' power efficiency. digital.library.unt.edu/ark:/67531/metadc804939/
Addressing Multicultural Issues in the Counselor Education Classroom: a Phenomenological Analysis
Multicultural education in counselor education is a popular topic among counselor educators and scholars. To date, scholars have focused on understanding the experiences of counselor educators who teach dedicated multicultural courses. However, less attention has been given to other counselor educators who are required by ethical and training standards to address multicultural issues across the curriculum. The purpose of this study was to understand counselor educators’ experiences addressing multicultural issues in courses that do not have a specific multicultural or diversity focus. I used phenomenological methodology to explore the experiences of counselor educators who hold doctoral degrees in counseling or a related field, have taken a multicultural/diversity course in their graduate training, are full-time clinical or tenure-line faculty members in CACREP-accredited programs, and have never taught courses dedicated to multicultural or diversity issues. Twelve participants (six men and six women), ranging in age ranged from 31 to 65, participated in the study. Ten participants identified as White, one African-American, and one Hispanic. The research team identified eight themes: (1) reasons for avoidance, (2) constraints, (3) qualities and practices, (4) educator as a factor in student development, (5) infusion, (6) personal background, (7) awareness of biases and assumptions, and (8) counselor educator responsibility/gatekeeping. Findings from this study will add to the literature regarding infusion of multicultural issues across the curriculum. Additionally, the implications offered will serve as a resource for counselor educators as they experience unique personal and professional challenges when addressing multicultural issues in classrooms beyond the main multicultural or diversity course offered in counseling programs. Implications for this study may lead to development of more focused guidelines on how to increase the increase the comfort of counselor educators as they facilitate multicultural discussions and assist counselors-in-training in working toward cultural competence. digital.library.unt.edu/ark:/67531/metadc822760/
Addressing Social Elements of Wildfire: Risk, Response, and Recovery in Highland Village, TX
Representatives of the City of Highland Village expressed concern over the risk of wildfires for their community. Anthropology provides many tools for and examples of disaster assessment of preparedness, response, recovery, and mitigation. These tools combined with Geographic Information Systems (GIS) can provide a holistic, cultural ecological look at how such a disaster may take place in the city. The project's methods included a detailed survey of preparedness steps which was analyzed using SPSS and also imported into ArcGIS for spatial analysis, and semi-formal, in-depth interviews with residents of the community regarding preparedness, response, and recovery. Residents fell into a middle category of preparedness, with the majority of participants considering or implementing a few recommended preparedness steps. Interview participants expressed respect for and trust of the city and first-responders, as well as a willingness to volunteer their help during response and recovery stages. Finally the American Community Survey showed that resident socioeconomic vulnerability was considerably low, and no action needed to be taken to advocate for at-risk individuals. Overall, the City of Highland Village showed a high resiliency to disaster. A wildfire likely will not have a major impact on the community as a whole, though the city may reduce the impact even further by informing the public of their risk, clearing natural areas of dead brush, sharing preparedness and evacuation information via social media and newsletters, and planning relief stations for those who may have been impacted. digital.library.unt.edu/ark:/67531/metadc849756/
ADHD Symptomology and Overweight Among College Men
Attention deficit/hyperactivity disorder (ADHD) is a childhood disorder that often persists into adulthood. Among adults, ADHD is highly comorbid with addictive behaviors (e.g., substance abuse and dependence), and depressive disorders. Recently, an association between ADHD and obesity has been reported in the literature; emotional and binge eating may be “addictive behaviors” that contribute to weight gain in this population. The purpose of this study was to test competing models of the hypothesized link between ADHD symptomology and overweight. Specifically, in Model 1, symptoms of depression are expected to mediate the relationship between symptoms of impulsivity and inattention and emotional and binge eating which, in turn, leads to weight gain (i.e., increased BMI). In Model 2, however, the impulsive symptoms have direct relationships with emotional and binge eating in addition to being mediated by depressive symptoms. Structural equation modeling (SEM) was employed to test how the models fit the data of 790 college men. Both models fit the data well, with Model 2 being preferred because of its greater connection to theory. All paths were significant indicating that increased impulsive and inattentive symptoms predicted increased symptoms of depression that, in turn, predicted increased emotional/binge eating, which has a direct and positive relationship with increased BMI. Moreover, impulsive symptoms were also directly related to emotional/binge eating, suggesting different paths to overweight across ADHD subtypes. The findings of the current study elucidate the links between ADHD symptoms and overweight (i.e., increased BMI). digital.library.unt.edu/ark:/67531/metadc103337/
Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods
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Two-dimensional (2D) transition metal dichalcogenides (TMDs) show great potential for the future electronics, optoelectronics and energy applications. But, the studies unveiling their interactions with the host substrates are sparse and limits their practical use for real device applications. We report the facile nano-scratch method to determine the adhesion energy of the wafer scale MoS2 atomic layers attached to the SiO2/Si and sapphire substrates. The practical adhesion energy of monolayer MoS2 on the SiO2/Si substrate is 7.78 J/m2. The practical adhesion energy was found to be an increasing function of the MoS2 thickness. Unlike SiO2/Si substrates, MoS2 films grown on the sapphire possess higher bonding energy, which is attributed to the defect-free growth and less number of grain boundaries, as well as less stress and strain stored at the interface owing to the similarity of Thermal Expansion Coefficient (TEC) between MoS2 films and sapphire substrate. Furthermore, we calculated the surface free energy of 2D MoS2 by the facile contact angle measurements and Neumann model fitting. A surface free energy ~85.3 mJ/m2 in few layers thick MoS2 manifests the hydrophilic nature of 2D MoS2. The high surface energy of MoS2 helps explain the good bonding strength at MoS2/substrate interface. This simple adhesion energy and surface energy measurement methodology could further apply to other TMDs for their widespread use. digital.library.unt.edu/ark:/67531/metadc849762/
Adlerian Play Therapy: Effectiveness on Disruptive Behaviors of Early Elementary-Aged Children
Approximately 20% of children experience serious mental health problems severe enough to meet diagnosis criteria, and less than one third of these children receive the services they need. Identifying effective school-based counseling interventions provides a viable and accessible solution, especially for families with financial barriers. This randomized, controlled outcome study examined the effectiveness of Adlerian play therapy (AdPT) compared to reading mentoring (RM) with 58 kindergarten through third grade students who qualified with clinical levels of disruptive behavior in the classroom. Participants were identified as 48% Latino, 33% European American, and 19% African American. Approximately four-fifths of participants were male. Children were randomly assigned to AdPT (experimental group) or RM (active control group) for 16 sessions of treatment. Children in both groups participated in twice weekly, individual, 30-minute interventions that took place in their schools. Results from a two (group) by two (repeated measures) split plot ANOVA indicated that, compared to the RM group over time, the AdPT group demonstrated statistically significant improvement on (a) disruptive behaviors in the classroom, as directly observed by objective raters and as reported by teachers, and (b) stress in the teacher-child relationship, as reported by teachers. Teachers and observers were blinded to children's treatment group assignment. AdPT demonstrated moderate to large effect sizes on all measures, indicating the practical significance of treatment. Further, 72% of children receiving AdPT improved from clinical/borderline levels of disruptive behavior problems to more normative functioning post-intervention, demonstrating the clinical significance of results. Whereas further research is warranted, results from this preliminary study are promising and support the use of AdPT in elementary schools to meet the needs of children exhibiting disruptive classroom behavior. digital.library.unt.edu/ark:/67531/metadc30494/
Adolescent Behavior Problems and Interparental Conflict: the Moderating Role of Parent-child Attachment
The current study examined the role that parent-child attachment plays in the relationship between marital conflict and the development of behavior problems in adolescents. To evaluate the hypothesis that attachment moderates this relationship, 57 families were recruited via e-mail invitation sent to families that participated in local church youth groups, school organizations, and a treatment program designed for adolescents with behavior problems. One custodial parent and his/her adolescent child completed an online or paper version of a survey consisting of the Achenbach’s Behavior Checklists, the Inventory of Parent and Peer Attachment, and the Children’s Perception of Interparental Conflict Scale. Hypotheses were evaluated using Baron and Kenny’s (1986) procedures to test moderating effects with multiple regression analyses. Mother attachment demonstrated a significant moderation effect between the intensity of interparental conflict and the parent’s report of externalizing behavior problems. Specifically, at low conflict intensity levels, relative to low attachment security, high attachment security was associated with fewer externalizing behavior problems, whereas at high intensities of interparental conflict high attachment security was associated with more externalizing behavior problems. digital.library.unt.edu/ark:/67531/metadc407793/
Adolescent Task Management: Multitasking and Social Media in the Student Search Process
This study examines adolescent students at an American international school and observes student use of social networking programs as well as physical actions in the search process. The study specifically observed multitasking behavior and organizational skills among students, as well as linkages made through social networking sites. Student observations, student interviews, analysis of Facebook entries, and a survey on multitasking yielded rich data. Students appear to be far more organized than previously suggested in the literature, and in this study, the organization proved to be largely self-taught. Students used their social networks to build a kind of group expertise that compensated for their youthful naivety. Students exhibited self-control within the search to the degree that they could focus on what they wanted to find, and they used heuristics—mental shortcuts—to achieve what they needed. Searches also suggest creativity in that students were flexible in their search methods and used a number of tools to gather information. Students could balance the needs of the academic or imposed search with their own online lives, meaning that they made compensations for social media and media multitasking when it was deemed necessary. digital.library.unt.edu/ark:/67531/metadc500064/
The Adoption, Management, and Performance of Local Government Investment Pools: A Comparative Analysis of State Practices
This dissertation examines the factors influencing a state’s decision to adopt a local government investment pool (LGIP), the institutional arrangements used in managing them, and the effect of the institutional types on LGIP performance. The dissertation extends the policy adoption theory with insights from investment theory to demonstrate that management credibility influences the likelihood of a state’s LGIP adoption. The study finds that the quality of financial management, the quality of professional leadership, proximate state neighbors who have previously adopted an LGIP, and economic factors determine a state’s proclivity to policy adoption. The dissertation also describes the institutional arrangements used in managing LGIPs and develops typologies based on their institutional arrangements. The dissertation compares LGIPs depending on the risk aversion of their institutional arrangements. The research extends the risk-return tradeoff in investment theory to LGIP institutional arrangements. The empirical findings show that LGIP institutional arrangement that has greater risk report higher performance. The dissertation also finds that competition in the LGIP market due to multiple vendors, and periods of economic recession account for higher performance because of higher risk-taking behaviors associated with them. This dissertation promotes public funds investment laws that emphasize prudent management of government finances and guides managers of the public purse on the types of institutional choices that optimize returns with minimal risk. digital.library.unt.edu/ark:/67531/metadc849621/
The Adoption of Open Source Software in Uganda: a Pragmatist Approach to the Formation of a National Information Policy for a New Technology
This exploratory research examined an information policy formation process for the adoption of open source software (OSS) in Uganda. Grounded in a pragmatist tradition, this theoretical and empirical study pursued a qualitative research approach with a triangulation of theoretical concepts, data collection, and analysis techniques in an iterative and interactive process. The design provided a powerful context to develop and conduct field activities in Kampala with a purposeful sample of 22 participants, 20 in interviews and 5 in a focus group discussion. The research design enhanced consistency in the evidence from the data, increased robustness in the results, and confidence in the findings. The results highlighted a vibrant ICT sector in Uganda, underlined the multiple stakeholders and their competing interests in the policy, revealed a lack of consensus between the government and OSS promoters on the meaning of OSS, and illuminated the benefits in the OSS model over proprietary software. The stakeholders' conflicting perceptions appear to be too far apart to allow meaningful progress and are derailing the policy. Unless their conflicting perceptions are resolved, the OSS policy will continue stagnating. The study fills critical information gaps in Uganda’s policy formation processes, provides timely and relevant information to holistically understand a complex policy formation stage to enable stakeholders to resolve their impasse and enact a law to embrace OSS. It breaks ground in information policy research in framing policy formation processes for new ICTs, such as OSS, as ideologically-oriented. The findings offer ideas to scholars and African countries to draw applicable lessons. digital.library.unt.edu/ark:/67531/metadc500076/
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