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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

Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

Description: 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.
Date: August 2013
Creator: Fogueri, Uma
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.
Date: December 2000
Creator: Sunday, William G.
Partner: UNT Libraries

The Academic Steroid: Nonmedical Use of Prescription Stimulants at a North Texas University

Description: 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.
Date: December 2014
Creator: Pennington, Cody W.
Partner: UNT Libraries

Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers

Description: 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.
Date: May 2016
Creator: Vaughan, Haydn
Partner: UNT Libraries

Accuracy of Self-Reported Height, Weight, and Calculated BMI and Resulting FITNESSGRAM® Healthy Fitness Zone Classification

Description: The determination of adiposity in adolescents is often assessed with calculations of body mass indices (BMI). Researchers often obtain these measurements from self-reported (SR) values. The purpose of this study was to determine the accuracy of SR height, weight, and calculated BMI (from height and weight). SR and actual measured (ME) BMI values were compared with standards from the FITNESSGRAM® Healthy Fitness Zone (HFZ) classifications. SR height and calculated BMI were found to be accurate while SR weight was, on average, underreported by 4.77 lbs. Because of these errors in SR height and weight, accuracy of classification into the FITNESSGRAM® HFZ was compromised. Consequently, it is important that researchers ascertain actual values of height and weight when measuring adolescents rather than use those from self-reports.
Date: May 2006
Creator: Rowell, Chelsie Joyce
Partner: UNT Libraries

Accuracy Variations in Human Facial Identification Based on Time of Exposure.

Description: This study examined the relationship between time of exposure to the human face and accurate subsequent photo line-up identification. A volunteer group of 124 undergraduate students was divided into three approximately equal sized subgroups. The three groups were then exposed to a video or a portion of a video depicting a theft. Exposure times ranged from two minutes to 30 seconds. The subjects were then given a questionnaire and shown a photo line-up of the mock perpetrator and five foils. Subjects were asked to identify the perpetrator and mark that identification on the questionnaire. Results of the experiment indicated that the longer a subject was exposed the greater the possibility of an accurate identification.
Date: December 2006
Creator: Cowle, Kenneth M.
Partner: UNT Libraries

Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses

Description: 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.
Date: December 2014
Creator: Zeng, Wei Rong
Partner: UNT Libraries

Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods

Description: 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.
Date: May 2016
Creator: Wu, Min
Partner: UNT Libraries

Adolescent Insomnia as a Predictor of Early Adulthood Outcomes

Description: Recent research found insomnia is a risk factor for psychiatric disorders in adults. To see if the same would be true in adolescents, the current study re-analyzed data from a national longitudinal study collected by ADDHealth that evaluated health behaviors in 4552 adolescents (mean age 14.9 years [SD 1.7]) at baseline and again 7-8 years later (n = 3489) during young adulthood. Insomnia was reported by 9.2% of the adolescents. Cross-sectionally, adolescent insomnia was associated with alcohol, cannabis, non-cannabis drugs, and tobacco use, and depression after controlling for gender and ethnicity. Prospectively, adolescent insomnia was a significant risk factor for depression diagnosis, suicidal ideation, and the use of depression and stress prescription medications in young adulthood after controlling for gender, ethnicity, and significant baseline variable. In addition, a trend was noted for suicidal attempts.
Date: December 2006
Creator: Roane, Brandy Michelle
Partner: UNT Libraries

African Refugee Parents' Involvement in Their Children's Schools: Barriers and Recommendations for Improvement

Description: The purpose of this study was to examine involvement of African refugee parents in the education of their elementary school children. The setting of the study was Northern and Southern Texas. African refugee parents and their children's teachers completed written surveys and also participated in interviews. In the study's mixed-method design, quantitative measures provided data about parent involvement at home, parent involvement at school, frequency of parent-teacher contact, quality of parent-teacher relationship, parent endorsement of children's schools, and barriers to parent involvement. Qualitative data from the open-ended questions provided data on barriers and strategies to improve involvement. Sixty-one African refugee parents responded to the survey and also participated in an in-depth face-to-face or telephone interview. Twenty teacher participants responded to an online survey. Quantitative data gathered from the parent and teacher surveys were analyzed using frequency distributions and analyses of variance. Qualitative data were analyzed by summarizing and sorting information into different categories using Weft QDA, an open-source qualitative analysis software. From these data, I identified barriers to African refugee parent involvement in their children's schools, as well as challenges that teachers face as they try to involve African refugee parents. Results of analyses of variance revealed statistically significant differences in parent involvement between African refugee parents with limited English proficiency and those with high English proficiency. A key finding of the research was that, whereas the overall level of parent involvement for African refugee parents was low, a major barrier to involvement was language. Teachers and parents cited enrolment in English as a second language programs as the best strategy to enhance parent involvement of African refugees. Additionally, parents who reported higher education levels were more involved in their children's education both at home and at school. All groups of African refugee parents reported high endorsement of their children's ...
Date: December 2009
Creator: Githembe, Purity Kanini
Partner: UNT Libraries

The Afro-British Slave Narrative: The Rhetoric of Freedom in the Kairos of Abolition

Description: The dissertation argues that the development of the British abolition movement was based on the abolitionists' perception that their actions were kairotic; they attempted to shape their own kairos by taking temporal events and reinterpreting them to construct a kairotic process that led to a perceived fulfillment: abolition. Thus, the dissertation examines the rhetorical strategies used by white abolitionists to construct an abolitionist kairos that was designed to produce salvation for white Britons more than it was to help free blacks. The dissertation especially examines the three major texts produced by black persons living in England during the late eighteenth centuryIgnatius Sancho's Letters of the Late Ignatius Sancho (1782), Ottobauh Cugoano's Thoughts and Sentiments on the Evil of Slavery (1787), and Olaudah Equiano's The Interesting Narrative of the Life of Olaudah Equiano, or Gustavus Vassa, the African (1789)to illustrate how black rhetoric was appropriated by whites to fulfill their own kairotic desires. By examining the rhetorical strategies employed in both white and black rhetorics, the dissertation illustrates how the abolitionists thought the movement was shaped by, and how they were shaping the movement through, kairotic time. While the dissertation contends that the abolition movement was rhetorically designed to provide redemption, and thus salvation, it illustrates that the abolitionist's intent was not merely to save the slave, but to redeem blacks first in the eyes of white Christians by opening blacks to an understanding and acceptance of God. Perhaps more importantly, abolitionists would use black salvation to buy back their own souls and the soul of their nation in the eyes of God in order to regain their own salvation lost in the slave trade. But ironically, they had to appear to be saving others to save themselves. So white abolitionists used the black narratives to persuade their overwhelmingly white audience ...
Date: December 1999
Creator: Evans, Dennis F.
Partner: UNT Libraries

Alexander Johnson's Ni' Concerto (1994) - Concerto no. 1 for Piano and Orchestra: a Discussion of Influences from Africa, Eastern and Western Europe

Description: In the new generation of artists emerging in South Africa, Alexander Johnson is considered the most prolific young composer of his day. In a recent review in the Pretoria News, Johnson has been praised by eminent critic Paul Boekkooi as a composer who has “an ear for the exotic and knows exactly how to bring it off....” He continued by noting that his music is “mentally engrossing, pleasurable to the senses and seems refreshingly free from dogmatic formulas." Johnson writes for musicians and the general public to equal satisfaction. His accessible compositions and catching use of melodic materials have made his writings very popular both in South Africa and abroad. During his residency in Belgrade in 1993-94, Johnson met Croatian pianist Dorian Leljak. Impressed with Johnson's compositional ideas and output, Leljak commissioned a work from Johnson for piano and orchestra. The result was the Niš Concerto, which Johnson completed in April 1994. The world premiere took place on June 23, 1994 with the Niš Philharmonic Orchestra conducted by Anatoli Nowiestski with Dorian Leljak as soloist. The Niš Concerto received its South African premiere in 1995 during a simultaneous celebration for “Europe Day” and the new democracy of the Republic of South Africa. The Delegation of the European Commission of South Africa sponsored the celebration, which took place in the Aula Auditorium on the campus of the University of Pretoria. The performers included the Artium Symphony Orchestra, conducted by Dutch-born Prof. Henk Temmingh and Johnson himself as piano soloist.
Date: August 2001
Creator: Malan, Petronel
Partner: UNT Libraries

Alternative Information Processing Formats for Overcoming Information Processing Deficits in Senior Adults

Description: The objective of this study was to examine the effectiveness of alternative advertising presentation formats, and the quantity of information presented in advertisements in overcoming possible information-processing deficits in senior adults that could affect their recall of ad attributes and brand name, the cognitive responses generated, and attitude toward the ad. In addition, the study examined the effectiveness of retirement status as a classification or segmentation variable in comparison with the use of the more traditional classification variable, chronological age. A convenience sample of senior adult volunteers from church groups, social clubs, and civic organizations from the local area were randomly assigned to one of nine experimental conditions. The experiment utilized a simulated magazine to test the effects of presentation formats (3 levels), and quantity of information (3 levels) on senior adult's recall, cognitive responses and attitude toward the test ads. Covariates (gender, wealth, education, activity level, health, and income) were used to reduce variance. The findings clearly indicate that the presentation format of the can ad adversely affected the memory of some senior adults. In addition, the results were significantly different across the different age levels. Retirement status was less beneficial than chronological age in the current study, but did reveal a marginally significant difference between seniors due to the number of attributes contained in the test ads. The implication of findings for advertisers and those who design marketing communications for seniors are numerous, and relate to the marketer's communication goals. Senior adults may prefer print media, but the inappropriate use of presentation format and the number of product attributes in the ads could have an adverse and significant impact when communicating with senior adults. Recognition of the information-processing differences of senior adults would result in more effective marketing communications for this rapidly growing and important segment of our ...
Date: December 2000
Creator: Muller, Lynn F.
Partner: UNT Libraries

American Blitzkrieg: Courtney Hodges and the Advance Toward Aachen (August 1 - September 12, 1944)

Description: This is an analysis of combat operations of US First Army under the command of Courtney Hodges, between August 1 and September 12, 1944, with an emphasis upon 1st, 4th, 9th, and 30th Divisions. However, other formations are necessarily discussed in order to maintain context. Indeed, many historians have failed to emphasize the complex interdependent nature of these efforts, and the traditional narrative has been distorted by inadequate situational awareness. This study argues that the army's operations were exceedingly difficult, resulting in approximately 40,000 casualties over a six week period. Although historians claim that the Germans were essentially defeated by the end of July, and that the Allied advance was subsequently halted by logistical difficulties, the official combat records clarify that logistical shortages were a tertiary factor, as the enemy remained capable of strong resistance. Consequently, defensive efforts were the primary factor hindering the advance, in conjunction with deteriorating weather conditions, rugged terrain, and surprisingly severe traffic congestion. Although this was mobile warfare, military theorists have overestimated the effectiveness of mechanization and underestimated the potential for antitank defenses. Ultimately, this study asserts that First Army was the primary American combat formation, and historians have exaggerated the importance of George Patton's Third Army. Therefore, in order to understand an American way of war, the combat operations of First Army deserve far more attention than they have previously received. This narrative thus emphasizes forgotten battles, including: Tessy, St. Sever, Tete, Perriers, Mayenne, Ranes, Flers, Mace, Elbeuf, Mantes, Corbeil, Sevran, Mons, Cambrai, Philippeville, Dinant, and Aubel.
Date: December 2012
Creator: Rinkleff, Adam J.
Partner: UNT Libraries

The American Doctrine for the Use of Naval Gunfire in Support of Amphibious Landings: Myth vs. Reality in the Central Pacific of World War II.

Description: The United States Marine Corps and the United States Navy developed during the interwar period a doctrine that addressed the problems inherent in the substitution of naval gunfire for artillery support in an amphibious assault. The invasion of Betio Islet, Tarawa Atoll, in November of 1943 was the first test of this doctrine. It has been said many times since the war that the doctrine basically passed this test and that lessons learned at Tarawa increased the efficiency with which the Marine Corps and Navy applied the prewar doctrine during the rest of the war. An analysis of the planning and execution of naval bombardments in the Central Pacific Campaign, after the invasion of the Gilberts, does not support this claim. This analysis leads the researcher to three conclusions. First, the Japanese developed defenses against many of the effects of the gunfire support doctrine that blunted much of the force of American firepower. American planners were slow to recognize the implications of these changes and, consequently, were slow to react to them. Second, many naval commanders responsible for providing naval gunfire support for Central Pacific operations still equated tonnage of ordnance to effectiveness of bombardment, regardless of their frequent references to "the lessons of Tarawa." Finally, strategic concerns and outright ignorance played a large part in determining the use of naval gunfire, the first taking precedence over the "lessons" and the second leading to the ignoring of the "lessons" all together.
Date: December 2006
Creator: Mitchener, Donald Keith
Partner: UNT Libraries

American Indian Worldviews, Risk Perceptions and Disaster Planning: an Exploratory Study

Description: It is commonly assumed that when confronted with an imminent hazard that people will react rationally, and prepare for, or at least attempt to avoid, danger from pending disasters. However, this conventional wisdom is not as evident as it appears. People prepare for, react to, or take social action to avoid hazards when they perceive the risk of danger to be threatening enough to warrant action, providing one has the will, insight and resources to do so. However, not all people perceive risks similarly. Risk is perceived differently by different people which affects risk perception and responses to hazards. This dissertation explores the relationships between American Indian worldviews, risk perceptions and disaster planning. To carry out this research 28 American Indians were interviewed. The sample consists of 14 American Indians residing in a rural are on the northern plains and 14 urban American Indians. The results only partially support that worldview is linked to risk perception and subsequent disaster planning. Other factors found to relate to risk perception and disaster planning for this non-representative sample of American Indians include various forms of social vulnerability.
Date: December 2013
Creator: Bales, Rodney A.
Partner: UNT Libraries

Americans Who Would Not Wait: The American Legion of the Canadian Expeditionary Force, 1915-1917

Description: This dissertation examines the five battalions of the Canadian Expeditionary Force designated as the American Legion. Authorized in Canada between 1915 and 1917, these units were formed to recruit volunteers from the United States to serve in the Canadian Overseas Contingent during the First World War. This work reviews the organization of Canada’s militia and the history of Anglo-American relations before examining the Canadian war effort, the formation of the American Legion, the background of its men, and the diplomatic, political, and constitutional questions that it raised. Much of the research focuses on the internal documents of its individual battalions (the 97th, 211th, 212th, 213th and 237th) and the papers of Reverend Charles Bullock now housed at the Public Archives of Canada. Documentation for the diplomatic furor the American Legion caused comes largely through the published diplomatic documents, British Foreign Office records held at the Public Record Office at Kew, and United States Department of State files at the National Archives at College Park, Maryland. The most useful sources for American Legion correspondence are the Beaverbrook papers held at the House of Lords Record Office, the papers of Canadian Prime Minister Sir Robert Laird Borden, and those of the Governor-General, the Duke of Connaught found in the Public Archives of Canada. During its brief existence the American Legion precipitated diplomatic and political problems in the United States, the United Kingdom, and the Dominion of Canada. Among the issues raised by the controversy surrounding the American Legion were: the relationship between the dominion government in Canada and the British government; the structural problems of imperial communications; the rise of a Canadian national identity and the desire for greater autonomy; and, the nature of citizenship and expatriation. This dissertation is also a long overdue account of the thousands of United States citizens ...
Date: August 2012
Creator: Smylie, Eric Paul
Partner: UNT Libraries

Analysis and Optimization of Graphene FET based Nanoelectronic Integrated Circuits

Description: Like cell to the human body, transistors are the basic building blocks of any electronics circuits. Silicon has been the industries obvious choice for making transistors. Transistors with large size occupy large chip area, consume lots of power and the number of functionalities will be limited due to area constraints. Thus to make the devices smaller, smarter and faster, the transistors are aggressively scaled down in each generation. Moore's law states that the transistors count in any electronic circuits doubles every 18 months. Following this Moore's law, the transistor has already been scaled down to 14 nm. However there are limitations to how much further these transistors can be scaled down. Particularly below 10 nm, these silicon based transistors hit the fundamental limits like loss of gate control, high leakage and various other short channel effects. Thus it is not possible to favor the silicon transistors for future electronics applications. As a result, the research has shifted to new device concepts and device materials alternative to silicon. Carbon is the next abundant element found in the Earth and one of such carbon based nanomaterial is graphene. Graphene when extracted from Graphite, the same material used as the lid in pencil, have a tremendous potential to take future electronics devices to new heights in terms of size, cost and efficiency. Thus after its first experimental discovery of graphene in 2004, graphene has been the leading research area for both academics as well as industries. This dissertation is focused on the analysis and optimization of graphene based circuits for future electronics. The first part of this dissertation considers graphene based transistors for analog/radio frequency (RF) circuits. In this section, a dual gate Graphene Field Effect Transistor (GFET) is considered to build the case study circuits like voltage controlled oscillator (VCO) and low ...
Date: May 2016
Creator: Joshi, Shital
Partner: UNT Libraries

An Analysis of EC-4 Pre-Service Teacher Perceptions of Knowledge and Use of Classroom Discipline Techniques

Description: The purpose of this study was to examine the perceptions of pre-service Texas Wesleyan University teachers' knowledge and use of classroom discipline techniques. The study was conducted to obtain data utilized for the evaluation of the research questions. A non-experimental, mixed research design using survey methodology was used. Part one of the Allen Classroom and Discipline Management Instrument (ACDMI) consisted of demographic information: current position, ethnicity, level of education, gender, age, teaching certification obtained, teaching certification anticipated to be obtained, type of teacher certification training, and number of clock hours received in discipline management. The demographic information was used as independent variables for comparing responses to survey items. Part two contained discipline management techniques from Skinner, Canter, Dreikurs, Gathercoal, Glasser, Faye and Funk, Curwin and Mendler, and Berne and Harris. These techniques were used to determine mean differences with the independent variables. Finally, part three was the qualitative section which consisted of four questions requesting information about helpful discipline techniques. The sample population consisted of 150 pre-service teachers from a small liberal arts university in Texas. Findings from the study indicated that EC-4 pre-service teachers' predicted use of discipline management techniques were the ones in which they were most knowledgeable. Furthermore, EC-4 pre-service teachers reported to be most knowledgeable of the following discipline management techniques: "Student Input in Developing Classroom Rules," "Social Reinforcement and Praise," and "Direct Teach and Model Appropriate Behavior." In addition, certified EC-4 pre-service teachers had more knowledge of classroom discipline techniques than non-certified EC-4 pre-service teachers. The qualitative analysis revealed a consensus among all EC-4 pre-service teachers with regard to their training in discipline management. All EC-4 pre-service teachers indicated that their overall training was inadequate in the area of classroom discipline management and that more was needed.
Date: May 2006
Creator: Short, Selena Gutierrez
Partner: UNT Libraries

An Analysis of Major American Riots: Issues in Riots and Riot Control

Description: By conducting sound research to understand the concepts surrounding rioting and efficient riot response tactics, professionals, especially whose main job is to ensure the tranquility in the society, will be better prepared to deal with all kinds of civil movements. The purpose of this study, consequently, is to meet the growing need for educational materials in this area and to provide riot response case studies, which demonstrate the numerous administrative challenges faced by law enforcement decision makers. In this study, seven major riots from throughout the United States are discussed including the Hay Market Riot of 1886, the Watts Riot of 1965, and Los Angeles Riots of 1992. Each riot case is studied in five different and independent stages: the setting and pre-disturbance situation, basic causes of the event, the disturbance situation, the response to the riot, and the aftermath of the incident. The study of all of these stages is intended to help police administrators acquire a general perspective on collective violence, and help them prevent future occurrences in their jurisdictions. In this thesis a special reference is given to the deficiencies of American riot policing and some recommendations were formed accordingly. Therefore, the study concludes with a list of general recommendations, which are crucially important for concerned officials to pay attention before, during, and after a riot.
Date: August 2001
Creator: Cinoglu, Huseyin
Partner: UNT Libraries

An Analysis of Motivational Cues in Virtual Environments.

Description: Guiding navigation in virtual environments (VEs) is a challenging task. A key issue in the navigation of a virtual environment is to be able to strike a balance between the user's need to explore the environment freely and the designer's need to ensure that the user experiences all the important events in the VE. This thesis reports on a study aimed at comparing the effectiveness of various navigation cues that are used to motivate users towards a specific target location. The results of this study indicate some significant differences in how users responded to the various cues.
Date: December 2003
Creator: Voruganti, Lavanya
Partner: UNT Libraries

An Analysis of the Composition Process of Bartók's Eight Improvisations on Hungarian Peasant Songs, Op. 20

Description: This is a study of Bartók's compositional process as it relates to the Improvisations, Op. 20. The study, which focuses on the analysis of the draft manuscript 50PS1, compares the draft and other relevant sources with the final composition. Bartók's framework for the entire Improvisations is based on a compositional strategy of pairing individual improvisations combined with systematic revision of the draft copy by the introduction of tritones as tonal equivalents and movement by fifths from semitones, to achieve structural coherence in the individual improvisations. The tonic-dominant relationship is used to rearrange the individual improvisations in the draft and tritones as tonal equivalents are used to propel the movement between the improvisations to produce a coherent whole.
Date: May 2000
Creator: Kochbeck, Olivia M.
Partner: UNT Libraries

An analysis of the effects of high school student concurrent enrollment at Collin County Community College District.

Description: As efforts to provide seamless transitions from high school to college grow, so do the numbers of high school students who concurrently enroll in college courses across the country. The purpose of this study was to evaluate the effectiveness of various aspects of the concurrent enrollment program at Collin County Community College District in Texas. Six research questions were designed to address student success and continuing enrollment patterns after high school graduation, as well as evaluate differences in the various models of dual credit classes offered by the college. Literature related to concurrent enrollment and dual credit programs, senior year of high school, and part-time faculty effectiveness was reviewed. Student issues addressed include: grade performance of concurrent enrollment students compared to the general college population; the percentage of concurrent enrollment students who continue at the college after high school graduation; and a comparison of continuing concurrent enrollment students with a matched sample (based on high school class rank), on the student success factors of fall-to-spring retention rates, fall-to-fall retention rates, grade point averages, and completion rates. Findings were generally positive related to the impact of concurrent enrollment on students and their subsequent success at the college. Various models of offering concurrent enrollment courses were also evaluated as measured by student performance in subsequent courses. Analysis of variance was used to determine differences based on the location at which the courses were taught (high school, college campus, or a college center); differences based on the mix of students in the class (all from one high school; all high school representing several schools; or a mix of high school and college students); and differences based on the employment status of the instructor (full-time college instructor; part-time college instructor; or high school teacher). Differences were examined for the entire sample, and for the ...
Date: December 2003
Creator: Swanson, Kathrine Bridgett
Partner: UNT Libraries