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Nonlinear UV Laser Build-up Cavity: An Efficient Design

Nonlinear UV Laser Build-up Cavity: An Efficient Design

Date: May 2009
Creator: Rady, Nicholas Henry
Description: Using the concept of the build-up cavity for second harmonic generation to produce 243nm laser light, an innovative cavity is theoretically explored using a 15mm length CLBO crystal. In order to limit the losses of the cavity, the number of effective optical surfaces is kept to only four and the use of a MgF2 crystal is adopted to separate the harmonic and fundamental laser beam from each other. The cavity is shown to have an expected round trip loss of five tenths of a percent or better, resulting in a conversion efficiency greater than 65%.
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Nonparametric Estimation of Receiver Operating Characteristic Surfaces Via Bernstein Polynomials

Nonparametric Estimation of Receiver Operating Characteristic Surfaces Via Bernstein Polynomials

Access: Use of this item is restricted to the UNT Community.
Date: December 2012
Creator: Herath, Dushanthi N.
Description: Receiver operating characteristic (ROC) analysis is one of the most widely used methods in evaluating the accuracy of a classification method. It is used in many areas of decision making such as radiology, cardiology, machine learning as well as many other areas of medical sciences. The dissertation proposes a novel nonparametric estimation method of the ROC surface for the three-class classification problem via Bernstein polynomials. The proposed ROC surface estimator is shown to be uniformly consistent for estimating the true ROC surface. In addition, it is shown that the map from which the proposed estimator is constructed is Hadamard differentiable. The proposed ROC surface estimator is also demonstrated to lead to the explicit expression for the estimated volume under the ROC surface . Moreover, the exact mean squared error of the volume estimator is derived and some related results for the mean integrated squared error are also obtained. To assess the performance and accuracy of the proposed ROC and volume estimators, Monte-Carlo simulations are conducted. Finally, the method is applied to the analysis of two real data sets.
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Nontraditional name changes for men: Attitudes of men and women.

Nontraditional name changes for men: Attitudes of men and women.

Date: May 2008
Creator: Millspaugh, Jennifer Diane
Description: Recently, some men have taken their wives' last names upon marriage rather than following tradition. The goal of this study was to examine the attitudes that men and women have toward these nontraditional men. Ideological hegemony and social identity theory comprised the framework for examining participants' beliefs. A survey first elicited participants' extant sexist beliefs about men and the characteristics of a nontraditional man compared to a traditional man. An open-ended question further explored participants' opinions. The results indicated that benevolent sexism influences respondents' attitudes towards nontraditional men and that most respondents view nontraditional men as more nurturing and committed to their marriage than traditional men. The results further revealed a dichotomy of positive and negative attitudes towards nontraditional men indicating that society's feelings about nontraditional men are changing.
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Nontraditional students in community colleges and the model of college outcomes for adults.

Nontraditional students in community colleges and the model of college outcomes for adults.

Date: December 2005
Creator: Philibert, Nanette
Description: The purpose of this study was to examine three components of Donaldson and Graham's (1999) model of college outcomes for adults: (a) Prior Experience & Personal Biographies, (b) the Connecting Classroom, and (c) Life-World Environment, and to assess their application to traditional and nontraditional students in community colleges in both technical and nontechnical courses. The study sample was comprised of 311 community college students enrolled in technical and nontechnical courses during fall 2005. A survey instrument was developed based on the three model components through a review of the literature. Demographic data collected were utilized to classify students into a technical or nontechnical grouping as well as four classifications of traditionalism: (a) traditional, (b) minimally nontraditional, (c) moderately nontraditional, and (d) highly traditional. This study found that nontraditional students vary from traditional students in regards to the three model constructs. A post hoc descriptive discriminate analysis determined that the Life-World Environment component contributed the most to group differences with the minimally nontraditional group scoring the highest on this construct.
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Nopalita: A Mythology of Cultural Self-Representation

Nopalita: A Mythology of Cultural Self-Representation

Date: August 2004
Creator: Medina, Cristina Blasa
Description: The first segment introduces the background information on the use of paños as art by prisoners and how I appropriate the same materials to create and record my own cultural mythology. The Statement of Problem and Questions are about how and what cultural information is chosen in creating a visual mythology. The second segment explains the invention of the mythology by describing why certain experiences were chosen, specifically those of the graduate school experience. Also the development of self-representation through self-portraits is described. The third segment explains the symbolism used in the imagery, such as the cacti as cultural indicator and palimpsest. The fourth segment is a conclusion involving the realization that feeling caught within a hybrid culture is an important part of my identity.
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North American Indian Mythology and Folklore for Secondary School Students

North American Indian Mythology and Folklore for Secondary School Students

Date: January 1970
Creator: Jackson, Sarah
Description: Through a study of North American Indian folklore and mythology, the non-Indian can at last begin to know the Indian with whom he has shared a continent and to find out something of his religion, traditions, history, humor, and tribal peculiarities. The approach to this study through motifs, already familiar to the students from other literature, offers a practical approach and one that can be adapted to classroom use, perhaps either in the study of myth, the study of literary types, the study of literature per se, or perhaps in the study of cultural differences.
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A Novel Mechanism for Site-Directed Mutagenesis of Large Catabolic Plasmids Using Natural Transformation

A Novel Mechanism for Site-Directed Mutagenesis of Large Catabolic Plasmids Using Natural Transformation

Date: August 2001
Creator: Williamson, Phillip C.
Description: Natural transformation is the process by which cells take up DNA from the surrounding medium under physiological conditions, altering the genotype in a heritable fashion. This occurs without chemical or physical treatment of the cells. Certain Acinetobacter strains exhibit a strong tendency to incorporate homologous DNA into their chromosomes by natural transformation. Transformation in Acinetobacter exhibits several unique properties that indicate this system's superiority as a model for transformation studies or studies which benefit from the use of transformation as an experimental method of gene manipulation. Pseudomonas putida is the natural host of TOL plasmids, ranging between 50 kbp and 300 kbp in size and encoding genes for the catabolism of toluene, meta-toluate, and xylene. These very large, single-copy plasmids are difficult to isolate, manipulate, or modify in vitro. In this study, the TOL plasmid pDKR1 was introduced into Acinetobacter calcoaceticus strains and genetically engineered utilizing natural transformation as part of the process. Following engineering by transformation, the recombinant DNA molecule was returned to the native genetic background of the original host P. putida strain. Specific parameters for the successful manipulation of large plasmids by natural transformation in Acinetobacter were identified and are outlined. The effects of growth phase, total ...
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A Novel Process for GeSi Thin Film Synthesis

A Novel Process for GeSi Thin Film Synthesis

Date: December 2007
Creator: Hossain, Khalid
Description: A unique process of fabricating a strained layer GexSi1-x on insulator is demonstrated. Such strained heterostructures are useful in the fabrication of high-mobility transistors. This technique incorporates well-established silicon processing technology e.g., ion implantation and thermal oxidation. A dilute GeSi layer is initially formed by implanting Ge+ into a silicon-on-insulator (SOI) substrate. Thermal oxidation segregates the Ge at the growing oxide interface to form a distinct GexSi1-x thin-film with a composition that can be tailored by controlling the oxidation parameters (e.g. temperature and oxidation ambient). In addition, the film thickness can be controlled by implantation fluence, which is important since the film forms pseudomorphically below 2×1016 Ge/cm2. Continued oxidation consumes the underlying Si leaving the strained GeSi film encapsulated by the two oxide layers, i.e. the top thermal oxide and the buried oxide. Removal of the thermal oxide by a dilute HF etch completes the process. Strain relaxation can be achieved by either of two methods. One involves vacancy injection by ion implantation to introduce sufficient open-volume within the film to compensate for the compressive strain. The other depends upon the formation of GeO2. If Ge is oxidized in the absence of Si, it evaporates as GeO(g) resulting in spontaneous ...
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Novel Role of Trypsin in Zebrafish

Novel Role of Trypsin in Zebrafish

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Date: May 2013
Creator: Alsrhani, Abdullah Falleh
Description: It has been shown previously in our laboratory that zebrafish produce trypsin from their gills when they are under stress, and this trypsin is involved in thrombocyte activation via PAR2 during gill bleeding. In this study, I investigated another role of the trypsin that is secreted from zebrafish. This investigation has demonstrated a novel role of trypsin in zebrafish. Not only did this investigation demonstrate the role of trypsin in zebrafish behavior, but also it showed that PAR2 might be the receptor that is involved in trypsin-mediated behavioral response. In addition, we have shown that Gq and ERK inhibitors are able to block the trypsin pathway and prevent the escaping behavior. Finally, the results of this investigation suggest that the cells that respond to trypsin are surface cells, which have an appearance similar to that of neuromast cells.
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Las Novelas de Gregorio López y Fuentes

Las Novelas de Gregorio López y Fuentes

Date: 1951
Creator: Fulwider, James H.
Description: This thesis considers the novels of Gregorio Lopez Y Fuentes.
Contributing Partner: UNT Libraries