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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

The immobilization of plant cells

Mak, A. L. January 1986 (has links)
No description available.
202

Metagenomic approaches to gene discovery.

Meyer, Quinton Christian January 2006 (has links)
<p>The classical approach to gene discovery has been to culture micro-organisms demonstrating a specific enzyme activity and then to recover the gene of interest through shotgun cloning. The realization that these standard microbiological methods provide limited access to the true microbial biodiversity and therefore the available microbial genetic diversity (collectively termed the Metagenome) has resulted in the development of environmental nucleic acid extraction technologies designed to access this wealth of genetic information, thereby avoiding the limitations of culture dependent genetic exploitation. In this work several gene discovery technologies was employed in an attempt to recover novel bacterial laccase genes (EC 1.10.3.2), a group of enzymes in which considerable biotechnological interest has been expressed. Metagenomic DNA extracted from two organic rich environmental samples was used as the source material for the construction of two genomic DNA libraries. The small insert plasmid based library derived from compost DNA consisted of approximately 106 clones at an average insert size of 2.7Kbp, equivalent to 2.6 Gbp of cloned environmental DNA. A Fosmid based large insert library derived from grape waste DNA consisted of approximately 44000 cfu at an average insert size of 25Kbp (1.1 Gbp cloned DNA). Both libraries were screened for laccase activity but failed to produce novel laccase genes. As an alternative approach, a multicopper oxidase specific PCR detection assay was developed using a laccase positive Streptomyces strain as a model organism. The newly designed primers were used to detect the presence of bacterial multicopper oxidases in environmental samples. This resulted in the identification of nine novel gene fragments showing identity ranging from 37 to 94% to published putative bacterial multicopper oxidase gene sequences. Three clones pMCO6, pMCO8 and pMCO9 were significantly smaller than those typically reported for bacterial laccases and were assigned to a recently described clade of Streptomyces bacterial multicopper oxidases.</p> <p><br /> Two PCR based techniques were employed to attempt the recovery of flanking regions for two of these genes (pMCO7 and pMCO8). The use of TAIL-PCR resulted in the recovery of 90% of the pMCO7 ORF. As an alternative approach the Vectorette&trade / system was employed to recover the 3&rsquo / downstream region of pMCO8. The complexity of the DNA sample proved to be a considerable technical challenge for the implementation of both these techniques. The feasibility of both these approaches were however demonstrated in principle. Finally, in an attempt to expedite the recovery of fulllength copies of these genes a subtractive hybridization magnetic bead capture technique was adapted and employed to recover a full &ndash / length putative multicopper oxidase gene from a Streptomyces strain in a proof of concept experiment. The StrepA06pMCO gene fragment was used as a &lsquo / driver&rsquo / against fragmented Streptomyces genomic DNA (&lsquo / tester&rsquo / ) and resulted in the recovery of a 1215 bp open reading frame. Unexpectedly, this ORF showed only 80% identity to the StrepA06pMCO gene sequence at nucleotide level, and 48% amino acid identity to a putative mco gene derived from a Norcardioides sp JS614.</p>
203

Detection of rabies virus in selected tissues of naturally infected skunks

Howard, Dennis Ray January 2011 (has links)
Digitized by Kansas Correctional Industries
204

The high finger piano technique in China: past, present, and future

Xu, Mo 01 May 2018 (has links)
The high finger piano technique is an approach to playing the piano which focuses on training the fingers to have extreme independence. The fingers are required to function in the extreme ranges of motion, lifting high before each strike of the key. This is an outdated technique from nineteenth century Europe, where the Lebert-Stark high finger school successfully promoted this technique in European conservatories. It was introduced to China at the beginning of the twentieth century, shortly after pianos began to be imported. From that point forward, this technique became the standard for Chinese pianists. Meanwhile, the high finger technique was abandoned by most pianists in the West in the twentieth century. Instead, the modern piano technique, which focuses on anatomical and scientific analysis, became the mainstream. In order to establish China’s place in the history of piano playing and technique, I will provide a brief overview of the history and how China developed from it. I will demonstrate evidence for why the high finger school became popular and why it persisted throughout the twentieth century. Finally, I will discuss current trends in Chinese piano pedagogy and provide a guide for how the future development of a healthy, informed technique might look.
205

VISUALISATION OF SPATIAL DATA QUALITY FOR DISTRIBUTED GIS

Yang, Ting, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2007 (has links)
Nowadays a substantial trend occurs that vast amounts of geospatial data are supplied, managed, and processed over distributed GIS. It is important to provide users with the capability of visualising spatial data quality information in a meaningful way for distributed GIS, since it will significantly enhance user understanding of data quality and aid them in assessing the data fitness for their application requirements. This thesis investigates the issue of visualisation of spatial data quality for distributed GIS. Based on a review of core concepts associated with spatial data quality, metadata standards, and major research areas related to data quality, the limitations of current data quality presentation are highlighted. To overcome some of these limitations, the research topic of this thesis is proposed, namely, adding visualisation functionality to the presentation of spatial data quality to convey uncertainty information to users in an interactive and graphical manner. Based on a review of the theories on visualisation and the frameworks developed for visualisation of spatial data quality in literature, an extended framework is developed incorporating several aspects of visualisation such as contexts, contents, and techniques, where the hierarchical nature of data quality and error models are two main parts of the visualisation contents. A brief framework of visualisation of spatial data quality for distributed GIS is proposed, where data storage with quality information and web services for visualising data quality are two key components. To satisfy a series of requirements for representing spatial data quality, a new object-oriented data model is proposed based on the review of developments of data models. This data model can specifically deal with the hierarchical nature of data quality and error propagation, recognising data quality as a dynamic process. Further, The implementation of the data model using GML and SVG is discussed. The details of a web service for visualising spatial data quality are addressed. After proposing the requirements on building a system for spatial data quality visualisation for distributed GIS, the design of a prototype visualisation system for distributed GIS is addressed in detail. The prototype visualisation system for spatial data quality is developed and implemented with an example data set, where SVG and JavaScript are used to illustrate how various graphic methods such as animation, data quality filters, and colour gradients can be used for distributed GIS. In addition to the visualisation of positional accuracy at the feature level, in this pilot system, the hierarchical structure of data quality information is also presented. Limitations of the research in this thesis are also addressed. However, in general, this research is of great significance for the contributions made to a relatively new research area in terms of theories, procedures, and software developments.
206

Development Of High Throughput Epigenomic Profiling Technologies And Their Application To Twin Based DNA Methylation Studies

Kaminsky, Zachary 24 September 2009 (has links)
Epigenetic studies hold the promise of addressing some of the fundamental questions of human biology including development, cell differentiation, and the aetiological mechanisms of complex disease. Over the last years, several new large scale high throughput technologies have been developed to allow genome wide profiling of epigenetic signals such as DNA methylation and histone modifications. Two of such technologies were developed in our laboratory enabling a genome wide microarray based profiling of DNA methylation signatures and a high throughput method for the site specific interrogation of the density of methylated cytosine. Using these techniques, we identified a DNA methylation difference in the 3’UTR of the DLX1 gene with potentially functional implications to discordance in risk taking behavior in a single pair of MZ twins. We modeled a power analysis on the effect size of the detected difference and determined that approximately 6~25 discordant twin pairs will be adequate to yield 80% power across the entire 12 K CpG island microarray platform using our epigenomic microarray profiling technique. We performed a DNA methylome analysis of MZ twins in white blood cells (WBC), buccal epithelial cells, and gut (rectum) biopsies (N=57 pairs in total) using 12K CpG island microarrays providing the basis for the first annotation of epigenetic metastability of ~6,000 unique genomic regions in MZ twins. We performed a classical twin study on DNA methylation differences in WBC and buccal epithelial cells from 39 pairs of MZ twins to 40 pairs of DZ twins. DZ co-twins exhibited significantly higher epigenetic difference compared to the MZ co-twins in buccal cells (p=1.2x10-294). While such higher epigenetic discordance in DZ twins can result from DNA sequence differences, our in silico SNP analyses and comparison of methylomes in inbred vs. outbred mice favour the hypothesis that this is due to epigenomic differences in the zygotes. This study suggests that molecular mechanisms of heritability may not be limited to DNA sequence differences.
207

Kinematic analysis of male olympic cross-country skiers using the open field skating technique

Heagy, Brian S. 15 September 1992 (has links)
The kinematic characteristics of 17 elite male cross-country skiers competing in the 50 km race of the 1992 Winter Olympic Games were determined. Each skier used the open field skating technique, one of four skating techniques used in free technique cross-country ski races. Skiers were filmed by the use of three video cameras, placed at a filming site on a flat portion of the racing course. Digitized data from the video were used to determine selected kinematic parameters which included: cycle velocity; cycle length; cycle rate; center of mass (CM) velocity vector angle; CM lateral displacement; CM lateral velocity; CM horizontal velocity; ski angles; ski edging angles; several types of pole angles; and hip, knee, and trunk angles. Temporal characteristics including strong side and weak side ski and pole phase times were also calculated. Cycle velocity and cycle length were found to be significantly related as were cycle velocity and the maximum strong side knee angle (r > .48, p < .05). Cycle velocity and the CM velocity vector angle were found to have only a moderate non-significant relationship as did cycle velocity and the strong and weak side ski angles. For those skiers using the open field skating technique, CM lateral motion (as measured by the CM velocity vector angle and the ski angles) did not seem to be a distinguishing factor between faster and slower skiers, as hypothesized. However, cycle length and the maximum strong side knee angle did seem to distinguish faster from slower skiers. Skiers who covered more distance throughout a cyde tended to have faster cycle velocities. Contributing to this increased distance could have been the thrust of the strong side ski. Skiers with the most strong side knee extension tended to ski the fastest. Thus, it seems that greater leg extension results in greater propulsive forces and greater velocity. / Graduation date: 1993
208

Development Of High Throughput Epigenomic Profiling Technologies And Their Application To Twin Based DNA Methylation Studies

Kaminsky, Zachary 24 September 2009 (has links)
Epigenetic studies hold the promise of addressing some of the fundamental questions of human biology including development, cell differentiation, and the aetiological mechanisms of complex disease. Over the last years, several new large scale high throughput technologies have been developed to allow genome wide profiling of epigenetic signals such as DNA methylation and histone modifications. Two of such technologies were developed in our laboratory enabling a genome wide microarray based profiling of DNA methylation signatures and a high throughput method for the site specific interrogation of the density of methylated cytosine. Using these techniques, we identified a DNA methylation difference in the 3’UTR of the DLX1 gene with potentially functional implications to discordance in risk taking behavior in a single pair of MZ twins. We modeled a power analysis on the effect size of the detected difference and determined that approximately 6~25 discordant twin pairs will be adequate to yield 80% power across the entire 12 K CpG island microarray platform using our epigenomic microarray profiling technique. We performed a DNA methylome analysis of MZ twins in white blood cells (WBC), buccal epithelial cells, and gut (rectum) biopsies (N=57 pairs in total) using 12K CpG island microarrays providing the basis for the first annotation of epigenetic metastability of ~6,000 unique genomic regions in MZ twins. We performed a classical twin study on DNA methylation differences in WBC and buccal epithelial cells from 39 pairs of MZ twins to 40 pairs of DZ twins. DZ co-twins exhibited significantly higher epigenetic difference compared to the MZ co-twins in buccal cells (p=1.2x10-294). While such higher epigenetic discordance in DZ twins can result from DNA sequence differences, our in silico SNP analyses and comparison of methylomes in inbred vs. outbred mice favour the hypothesis that this is due to epigenomic differences in the zygotes. This study suggests that molecular mechanisms of heritability may not be limited to DNA sequence differences.
209

The production of a limited hand-printed edition of a children's story book

Donelan, Martha Anne 03 June 2011 (has links)
There is no abstract available for this thesis.
210

An identification of policies and practices that hinder and facilitate the admission and retention of Hispanics in institutions of higher education

Cantu, Linda Valdez 12 April 2006 (has links)
The purpose of this study was to identify policies and practices that impact the admission and retention of Hispanics in higher education. The study did this by identifying those policies and practices that are currently being used and that facilitate or hinder institutions of higher education in the recruitment, admission, retention, and graduation of students, particularly Hispanic students. The researcher utilized the Delphi method to conduct the study. This research method produces a consensus of opinion from a group of individuals identified as experts in a given field. Three structured surveys were conducted. Each round of surveys had two questionnaires: (a) policies and practices that positively or negatively impact the admission of Hispanics in higher education and (b) policies and practices that positively or negatively impact the retention of Hispanics in higher education. Conclusions The Texas Academic Skills Program (TASP) is negatively affecting Hispanic students’ admission into Texas colleges and universities. Further, it is affecting the retention of Hispanic students in Texas institutions. If students do poorly on the TASP, they are placed in remedial courses. Even though students successfully complete all remediation courses (even with A’s & B’s), if they do not pass the TASP after remediation, they cannot continue college level work. This causes many students to become discouraged and leave college. Although college test makers, such as the Educational Testing Service (ETS), state that the SAT should be used as an assessment instrument, many Texas college’s continue to use it for admissions and awarding scholarships; both of which are contrary to test-makers’ recommendations. College admission tests are hindering the admission of Hispanic students into colleges and universities. Tuition costs, particularly where students depend heavily on loans, are keeping students from entering college, from continuing in college, and from pursuing graduate and post-graduate degrees.

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