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9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

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Date: May 2012
Creator: Nalam, Vamsi J.
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 ...
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Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

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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Date: August 2013
Creator: Fogueri, Uma
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 ...
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Academic Dishonesty:  Attitudes and Behaviors of Fundamentalist Christian College Students

Academic Dishonesty: Attitudes and Behaviors of Fundamentalist Christian College Students

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Date: December 2000
Creator: Sunday, William G.
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 ...
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The Academic Steroid: Nonmedical Use of Prescription Stimulants at a North Texas University

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

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Date: December 2014
Creator: Pennington, Cody W
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.
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Accuracy of Self-Reported Height, Weight, and Calculated BMI and Resulting FITNESSGRAM® Healthy Fitness Zone Classification

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

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Date: May 2006
Creator: Rowell, Chelsie Joyce
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.
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Accuracy Variations in Human Facial Identification Based on Time of Exposure.

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

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Date: December 2006
Creator: Cowle, Kenneth M.
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.
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Acute Effects of the Antibiotic Streptomycin on Neural Network Activity and Pharmacological Responses

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

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Date: December 2014
Creator: Zeng, Wei Rong
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.
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Adherence and Haemagglutination of Moraxella Catarrhalis.

Adherence and Haemagglutination of Moraxella Catarrhalis.

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Date: August 2000
Creator: Kosterman, Edward, III
Description: M. catarrhalis is a gram-negative diplococci frequently associated with infections of the upper respiratory tract. During the past decade, some preliminary studies have attempted to elucidate mechanisms of adherence and haemagglutination of M. catarrhalis. These studies have reported, in many cases, inconsistent results. There are two purposes of this research. First, identify mechanisms that may potentially be associated with the adherence and haemagglutination of M. catarrhalis. Second, suggest research directions that may be fruitful in clarifying these mechanisms.
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Adolescent Insomnia as a Predictor of Early Adulthood Outcomes

Adolescent Insomnia as a Predictor of Early Adulthood Outcomes

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Date: December 2006
Creator: Roane, Brandy Michelle
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.
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African Refugee Parents' Involvement in Their Children's Schools: Barriers and Recommendations for Improvement

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

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Date: December 2009
Creator: Githembe, Purity Kanini
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 ...
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