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9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

Description: 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 ...
Date: May 2012
Creator: Nalam, Vamsi J.
Partner: UNT Libraries

The 1896 Vienna Tonkünstler-verein Competition: the Three Award-winning Works and Seven Anonymous Submissions with Clarinet

Description: 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.
Date: August 2014
Creator: Harrell, Andrea
Partner: UNT Libraries

The 1986 National Endowment for the Arts Commission: An Introspective Analysis of Two Marimba Works

Description: The marimba is rapidly achieving greater importance as a solo percussion instrument. Solo compositions for the marimba have been commissioned and performed only in the last sixty years. The 1986 National Endowment for the Arts Solo Marimba Commission is considered one of the most important commissioning projects in the history of marimba literature. Two compositions created through this project, Velocities by Joseph Schwantner and Reflections on the Nature of Water by Jacob Druckman have become two of the most influential works in contemporary marimba music. This thesis will focus on a historical perspective of the project, as well as theoretical aspects and performance issues related to these two compositions. The National Endowment for the Arts (NEA) issued a consortium commissioning grant through the Percussive Arts Society (PAS) in 1986 to three internationally renowned marimbists, William Moersch, Leigh Howard Stevens and Gordon Stout. Three Pulitzer Prize winners were brought together to compose three new works for the marimba. The resulting pieces were: Reflections on the Nature of Water by Jacob Druckman, Velocities by Joseph Schwantner, and Islands from Archipelago: Autumn Island by Roger Reynolds. A brief history of the classical concert marimba and the development of solo marimba literature is provided in the second chapter. The fourth and fifth chapters provide individual information about the pieces, including concise biographical information about the composers and an analysis of the two compositions.
Date: August 2005
Creator: Fang, I-Jen
Partner: UNT Libraries

2D and 3D Fabrication Devices: Can They Improve Spatial Reasoning Skills in Children?

Description: The purpose of this study is to evaluate the potential benefit of two hours of activities involving 2D and 3D fabricators on the spatial reasoning skills of children in Grades 4 and 5, ages 9 to 10, from a private school in Southeast Texas. Can the introduction to hands-on activities with products created with these devices and learning about how these devices operate improve spatial reasoning skills? The research also evaluates the use of the Shapes Test as a valid measure of the spatial reasoning skills of children. The Cube Design and Spatial Memory subtests of the UNIT (Universal Nonverbal Intelligence Tests) were used for evaluating the spatial reasoning skills of the participants, based on their respected validity, along with a Shapes Test that is in development. Discussion regarding gender, language, and experiential theories of spatial reasoning skill development are included in the literature review.
Date: August 2016
Creator: Zimmerman, Ellen L
Partner: UNT Libraries

3D Reconstruction Using Lidar and Visual Images

Description: 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.
Date: December 2012
Creator: Duraisamy, Prakash
Partner: UNT Libraries

Aaron Copland's Concerto for Clarinet: A Lecture Recital, Together with Three Recitals of Music by Mozart, Rossini, Schumann, Brahms, and Contemporary European and American Composers

Description: The dissertation consists of four recitals: one chamber music recital, two solo recitals, and one lecture recital. The repertoire of these programs was chosen with the intention of demonstrating the capability of the performer to deal with problems arising in works of varying types and of different historical periods. The lecture recital, Aaron Copland's Concerto for Clarinet, begins with biographical information, followed by a discussion of various other works of the composer and of important stylistic traits that are contained therein. After thus setting the Concerto in perspective to other major works, an investigation is made into various aspects of form and style which make the Concerto atypical in some respects to the composer t total body of works. Particular emphasis is given to rhythmic and melodic characteristics of the piece which are related to jazz and Latin-American popular music. The formal and stylistic analysis is followed by a discussion of problems involved in performing the Concerto with a piano reduction of the orchestral part, and the lecture concludes with a survey of interpretative problems posed by the work. At the conclusion of the lecture portion of the presentation, the Concerto was performed.
Date: August 1971
Creator: Bullock, Bruce Lloyd
Partner: UNT Libraries

Ability Estimation Under Different Item Parameterization and Scoring Models

Description: A Monte Carlo simulation study investigated the effect of scoring format, item parameterization, threshold configuration, and prior ability distribution on the accuracy of ability estimation given various IRT models. Item response data on 30 items from 1,000 examinees was simulated using known item parameters and ability estimates. The item response data sets were submitted to seven dichotomous or polytomous IRT models with different item parameterization to estimate examinee ability. The accuracy of the ability estimation for a given IRT model was assessed by the recovery rate and the root mean square errors. The results indicated that polytomous models produced more accurate ability estimates than the dichotomous models, under all combinations of research conditions, as indicated by higher recovery rates and lower root mean square errors. For the item parameterization models, the one-parameter model out-performed the two-parameter and three-parameter models under all research conditions. Among the polytomous models, the partial credit model had more accurate ability estimation than the other three polytomous models. The nominal categories model performed better than the general partial credit model and the multiple-choice model with the multiple-choice model the least accurate. The results further indicated that certain prior ability distributions had an effect on the accuracy of ability estimation; however, no clear order of accuracy among the four prior distribution groups was identified due to an interaction between prior ability distribution and threshold configuration. The recovery rate was lower when the test items had categories with unequal threshold distances, were close at one end of the ability/difficulty continuum, and were administered to a sample of examinees whose population ability distribution was skewed to the same end of the ability continuum.
Date: May 2002
Creator: Si, Ching-Fung B.
Partner: UNT Libraries

Ability Grouping in College Beginning Media Writing Classes

Description: The problem with which this investigation is concerned is that students of unequal writing ability are frequently placed in the same beginning media writing classes in college journalism. It is difficult for a teacher to be effective when the ability of the students ranges from those who cannot write clear complete sentences to others whose work already appears in newspapers and magazines. The purpose of this study is to determine whether students who are ability grouped into slow—average and advanced groups do the same, better, or worse than heterogeneously grouped students. In the spring semester of 1987, students in Journalism 1345, Media Writing laboratory, at the University of Texas at Arlington, were given a pretest to determine how well they wrote a simple news story and a simple feature story. On the basis of that test, which was graded by three raters, the students were placed in two separate ability groups in three classes. The fourth class contained students with heterogeneous abilities who were not placed in groups. At the end of the semester a posttest was given in news and feature writing. A two-way analysis of variance was used to analyze the posttest scores of sixty-seven students. There was no significant difference in the posttest scores of students who were grouped homogeneously and those who were grouped heterogeneously. The difference in the scores of heterogeneously grouped advanced students and homogeneously grouped advanced students was not significantly different from the difference between the posttest scores of heterogeneously grouped slow-average students and homogeneously grouped slow-average students.
Date: December 1987
Creator: Haber, Marian Wynne
Partner: UNT Libraries

The Ability of Selected Economically Disadvantaged Black Children to Comprehend the Non-Identity Requirement of Pronominalization

Description: The problem with which this investigation is concerned is that of determining the ability of economically disadvantaged black children to comprehend a specific grammatical operation, the non-identity requirement of pronominalization. In addition, the study is also concerned with describing selected characteristics of the language of the subjects in the study through the utilization of a task of imitation. The subjects of the study were forty-eight black children who were between the ages of four and ten years. All subjects were from families in which the natural parents were living together in the same household. The parents and children were native residents of the area and were recipients of federal welfare aid. None of the subjects in the study had histories of physiological, psychological, neurological, or auditory problems, and none were presently enrolled in rehabilitative language programs. A general estimate of intelligence was provided by the administration of the Columbia Mental Maturity Scale.
Date: December 1973
Creator: Bountress, Nicholas George
Partner: UNT Libraries

Absalom, Absalom! A Study of Structure

Description: The conclusion drawn from this study is that the arrangement of material in Absalom, Absalom! is unified and purposeful. The structure evokes that despair that is the common denominator of mankind. It reveals both the bond between men and the separation of men; and though some of the most dramatic episodes in the novel picture the union of men in brotherly love, most of the material and certainly the arrangement of the material emphasize the estrangement of men. In addition, by juxtaposing chapters, each separated from the others by its own structural and thematic qualities, Faulkner places a burden of interpretation on the reader suggestive of the burden of despair that overwhelms the protagonists of the novel.
Date: August 1973
Creator: Major, Sylvia Beth Bigby
Partner: UNT Libraries

Absorption, Relaxation, and Imagery Instruction Effects on Thermal Imagery Experience and Finger Temperature

Description: A skill instruction technique based on cognitive behavioral principles was applied to thermal imagery to determine if it could enhance either subjective or physiological responsiveness. The effects of imagery instruction were compared with the effects of muscle relaxation on imagery vividness, thermal imagery involvement, and the finger temperature response. The subjects were 39 male and 29 female volunteers from a minimum security federal prison. The personality characteristic of absorption was used as a classification variable to control for individual differences. It was hypothesized that high absorption individuals would reveal higher levels of imagery vividness, involvement, and finger temperature change; that imagery skill instruction and muscle relaxation would be more effective than a control condition; and that the low absorption group would derive the greatest benefit from the imagery task instruction condition. None of the hypotheses was supported. Finger temperature increased over time during the experimental procedure but remained stable during thermal imagery. The results suggest that nonspecific relaxation effects may best account for finger temperature increases during thermal imagery. Results were discussed in relation to cognitive-behavioral theory and the characteristic of absorption.
Date: December 1986
Creator: Durrenberger, Robert Earl, 1951-
Partner: UNT Libraries

Absorptive Capacity: An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities

Description: 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 ...
Date: May 2012
Creator: Daspit, Josh
Partner: UNT Libraries

Academic Achievement and the Ability of Post-Secondary Students to Read Assigned Materials

Description: This study provides a rationale for adopting course materials. It demonstrates the relationship between ability to read assigned materials and academic achievement, and that selection of materials creates two groups having different probabilities of success. The sample was selected from a population of all students enrolled in Principles of Economics courses at North Texas State University in the spring semester of 1986. The Nelson-Denny Reading Test was used to determine reading ability. Assigned materials were analyzed for readability. A frustration level was determined and used to divide the sample: the group of interest, those with reading abilities below the frustration level who underwent the treatment of reading materials written above their ability to comprehend; and the comparison group, those with reading abilities above the frustration level who did not undergo the treatment.
Date: August 1987
Creator: Cohick, Mikel William
Partner: UNT Libraries

The Academic Achievement of College Freshmen with Regard to Demographic Variables and College Admissions Test Scores

Description: The problem with which this study is concerned was that of examining the relationship between academic achievement of college freshmen students and selected demographic variables. The purpose was to compare the grade point average of selected freshmen at North Texas State University and determine if geographic location, high school size, gender, racial heritage and college admission test scores affect academic achievement during the first year of college.
Date: May 1987
Creator: Bradford, Cindy L.
Partner: UNT Libraries

Academic Achievement of National Social Fraternity Pledges Compared to Non-Fraternity Students

Description: This study examined the academic achievement of national social fraternity pledges compared to non-fraternity students at the University of Texas at Arlington. It was done to determine whether significant differences existed between the grade point averages of pledges of social fraternities and those of students who did not pledge a social fraternity, and to determine whether significant differences existed among fraternities when compared with each other with respect to academic achievement. This study was meant to provide a research design that could be used by other colleges and universities with fraternities to conduct the same comparison of academic performance. In the fall semester of 1989, 164 pledges were selected as the population for the study to be matched with non-fraternity students based on Scholastic Aptitude Test (SAT) scores, age, sex, classification, academic major, and number of hours attempted. A T-test of like groups was performed on the entire population with no significant difference found at the .05 level between all the fraternity pledges and all the matched pairs. A T-test of like groups was performed on the pledges from each separate organization and there was a significant difference among three of the fraternities. Two of the fraternities had significantly higher grade point averages than those of their matched pairs, and one group of matched pairs had a significantly higher grade point average than the fraternity. Of the 17 fraternities, 12 had higher grade point averages than their matched pairs and five of the matched pairs had higher grade point averages than the fraternities. The results of this study show that objective data can be collected to address the issue of academic excellence comparing fraternity and non-fraternity populations. It is recommended that further study be conducted in this area to establish longitudinal data, with specific examination of the scholarship programs of ...
Date: August 1990
Creator: Gardner, Kent Lee
Partner: UNT Libraries

Academic Advising Professional Characteristics and Standards: Do Academic Advisors Follow Recognized Professional Standards in Their Work?

Description: 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.
Date: May 2014
Creator: Shelton, Kiesha R.
Partner: UNT Libraries

The Academic and Athletic Experiences of African-american Males in a Division I (Fbs) Football Program

Description: 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.
Date: December 2013
Creator: Salinas, Silvia M.
Partner: UNT Libraries

Academic, Behavioral, and Social Competency Characteristics of Non-Handicapped, Learning Disabled, and Emotionally/Behaviorally Disordered Adjudicated Juveniles

Description: The juvenile justice system is society's response to juvenile misconduct. In spite of numerous federal, state, and local programs, the problem of juvenile delinquency persists. An increasing number of juveniles are being taken into custody and placed in institutional settings. Although juvenile delinquents share a number of common general characteristics (e.g., sex, minority, lower socioeconomic status, a history of school failure), they are not a homogeneous group. Effective educational interventions with delinquent juveniles can meet their unique academic, vocational, and social skills deficits. Handicapped juveniles are disproportionately represented among juvenile correctional facility populations. The identification of handicapped juveniles among delinquent populations is compounded as they share many of the same general characteristics. Federal statutes require individualized educational programs for all handicapped juveniles. This research investigated academic, behavioral, and social competencies of non-handicapped and handicapped adjudicated youth. Specifically, this investigation assessed measures of academic performance, classroom behavior, self-esteem, and social behavior. ANOVA indicated statistically significant differences between non-handicapped, learning disabled, and emotionally/behaviorally disordered adjudicated juveniles in reading achievement, mathematics achievement, and teacher generated measures of classroom behavior.
Date: August 1990
Creator: Campbell, Robert E. (Robert Eugene)
Partner: UNT Libraries

Academic Dishonesty: Attitudes and Behaviors of Fundamentalist Christian College Students

Description: This study was designed to examine: (1) the extent to which cheating occurs in fundamentalist Christian colleges; (2) the attitudes of fundamentalist Christian college students toward cheating; (3) attitudes of fundamentalist Christian college students toward cheating among their peers; (4) the kinds of cheating practices of fundamentalist Christian college students; (5) the degree to which students engage in neutralizing behavior to justify cheating; (6) differences in cheating behaviors according to gender; (7) differences in cheating behaviors according to ethnicity; and (8) differences in cheating behaviors according to the length of duration of Christian commitment. Based upon the responses of 337 students attending 3 different Christian colleges, it was concluded that: (1) most Christian fundamentalist students do not engage in cheating; (2) respondents believe that each of 17 self-reported cheating behaviors are serious forms of cheating; (3) respondents are unlikely to report cheating among peers; (4) plagiarism is the most common cheating behavior; (5) most respondents justify cheating on the basis of the workload at school and the pressure to obtain good grades; (6) there are no differences in cheating behavior according to gender; (7) there are differences in cheating behavior according to groups; and (8) most respondents do not cheat regardless of the self-reported duration of Christian commitment.
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Date: December 2000
Creator: Sunday, William G.
Partner: UNT Libraries

Academic excellence and instructional expenditures in Texas.

Description: Public school per pupil costs and demands for better performance have increased over the past several decades. While the overall per pupil expenditures have increased, the percent of the educational dollar directed toward instructional activities has remained at approximately 60%. A grass-roots movement known as the "65% Solution" caught national attention by claiming that schools are not efficiently allocating resources into areas that have the greatest link to student achievement, such as instruction. Proponents of the 65% Solution claim that per pupil expenditures can be increased by shifting funds from areas considered non-instructional to areas that directly impact student instruction, such as teachers and instructional materials. The purpose of this study was to determine the relationship between district Panel Recommended and Commended Performance TAKS Reading/ELA and Math results and three measurements of instructional expenditures, Instructional Staff Percent; TEA Instructional Expenditure Ratio; and the NCES Instructional Expenditure Ratio (65% Solution), in Texas public schools. Data was collected from the 2003-2004 AEIS report. Multiple regression was used to conduct the analyses. In most instances, there was little, if any, relationship between TAKS Reading/ELA and TAKS Math, and the Instructional Staff Percent (ISP), TEA Instructional Expenditure Ratio (TIER), and NCES Instructional Expenditure Ratio (NIER). However, a low to moderate relationship was discovered in the comparison of TAKS Reading/ELA, and the ISP and TIER. This result was the same for both the Panel Recommended and Commended Performance. In every instance, the ISP and TIER showed positive, statistically significant, relationships to TAKS results. The NIER, or 65% Solution, had the lowest correlation and was statistically insignificant in three out of four analyses.
Date: August 2006
Creator: Helvey, Jearl Kenton
Partner: UNT Libraries