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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.
331

A Linkage Study of Chromosome IV in Barley

Smith, Earl William 01 May 1953 (has links)
Barley (Hordeum sp.) is a principal cereal crop throughout much of the world and is of great economic importance in the United States. Spring barley is a leading cereal crop in Utah. Barley has many desirable characteristics which make it an excellent plant for genetic studies. Some of these characteristics are low chromosome number, almost complete self-fertilization, relative ease of hybridization, and easily classified hereditary characters. The establishment of genes or factors at definite loci in linkage groups is a valuable aid in furthering breeding programs and the ultimate improvement of barley. All seven linkage groups have been established although the location of only a small number of genes is known in some of them and most of these genes were mapped from information obtained from crosses involving only two or three factor pairs. Theis thesis deals with determining the location of five genes belived to be in linkage group IV and to establish new linkages if possible. specifically planned crosses involving from tow to five of these genes were used in this study.
332

Biochemical and molecular genetic analysis of mutant androgen receptors in humans

Mhatre, Anand N. January 1992 (has links)
No description available.
333

Structural Topology Optimization Using a Genetic Algorithm and a Morphological Representation of Geometry

Tai, Kang, Wang, Shengyin, Akhtar, Shamim, Prasad, Jitendra 01 1900 (has links)
This paper describes an intuitive way of defining geometry design variables for solving structural topology optimization problems using a genetic algorithm (GA). The geometry representation scheme works by defining a skeleton that represents the underlying topology/connectivity of the continuum structure. As the effectiveness of any GA is highly dependent on the chromosome encoding of the design variables, the encoding used here is a directed graph which reflects this underlying topology so that the genetic crossover and mutation operators of the GA can recombine and preserve any desirable geometric characteristics through succeeding generations of the evolutionary process. The overall optimization procedure is tested by solving a simulated topology optimization problem in which a 'target' geometry is pre-defined with the aim of having the design solutions converge towards this target shape. The procedure is also applied to design a straight-line compliant mechanism : a large displacement flexural structure that generates a vertical straight line path at some point when given a horizontal straight line input displacement at another point. / Singapore-MIT Alliance (SMA)
334

Effects of X and Y chromosomes on body size and shape : anthropometric studies of 45,X females, 46,XY females, 46,XX males, 47,XXY males, and 47,XYY males /

Varrela, Juha. January 1984 (has links)
Thesis--University of Turku, 1984. / At head of title: From the Institute of Dentistry and the Institute of Biomedicine, University of Turku. Extra t.p. with thesis statement inserted. Also published in: Proceedings of the Finnish Dental Society, Vol. 80, 1984, Suppl. V. Includes bibliographical references.
335

X chromosome upregulation and its biological significance in mammals /

Nguyen, Di Kim. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 77-87).
336

Genomic analysis of sorghum by fluorescence in situ hybridization

Kim, Jeong-Soon 15 November 2004 (has links)
The reliability of genome analysis and proficiency of genetic manipulation in vivo and in vitro are increased by assignment of linkage groups to specific chromosomes, placement of centromeres, orientation with respect to telomeres, and linear alignment with respect to chromosomal features and dimensions. I undertook five studies aimed at integrating sorghum genomics and cytogenetics at several levels. The results help establish an entirely new "cyto-genomics" resource, impacts of which are likely to be broad. In the first study, I developed a FISH-based karyotyping system for Sorghum bicolor Moench. I used integrated structural genomic resources, including linkage maps and large-insert clonal libraries of sorghum genomic DNA to develop a 17-locus probe cocktail for simultaneous fluorescent in situ hybridization (FISH). This probe enabled facile identification of all chromosome pairs in mitotic chromosome spreads. Perhaps just as important, I established time-efficient means to select sorghum BAC clones for multi-probe FISH. Thus, an integrated cyto-genomics system for sorghum can be constructed without need of chromosome flow sorting or microdissection, both of which are difficult and costly. In the second study, hybridization of DNA clones from 37 different genomic regions enabled the assignment of linkage groups and orientation of linkage maps to chromosomes. Comparisons between genetic and physical distances throughout the genome enabled a new nomenclature for linkage group designation in sorghum. The results provide an integrated nomenclature system of Sorghum bicolor chromosomes and linkage groups. In the third study, I created high-resolution maps by FISH to pachytene bivalents for two linkage groups (B and H), and defined relationships between pericentromeric heterochromatin, centromeres, mapped markers and recombination rates. These relationships will help guide the development and use of sorghum genomics. In the fifth study, I used FISH in two ongoing gene-targeted efforts. For the maturity gene ma5 and fertility restoration gene rfl, I estimated physical lengths between currently available flanking molecular markers. This enables estimation of recombination densities in these regions and assessment of the applicability of map-based and -assisted cloning.
337

Analysis of the origin and spread of the domestic dog using Y-chromosome DNA and mtDNA sequence data

Oskarsson, Mattias January 2012 (has links)
The domestic dog was probably the first domesticated animal, and the only one to spread to all continents in ancient times. The dog is one of the most phenotypically diverse animals, a result of human selection throughout dog history. Studies of the genetic origins and early spread of domestic dogs is important to gather information about biological and cultural mechanisms behind domestication but also to investigate early human history. The step from a hunter and gatherer lifestyle to farming is one of the most important steps in human history. In this thesis I will present work aimed at understanding both domestic dog origins and dispersal. In order to be able to investigate dog origins based on a second haploid chromosome we identified 14,437 bp of Y-chromosomal DNA sequence. Based on this we show that dogs in Asia south of Yangtze River (ASY) has the highest genetic diversity and was founded from a large number of wolf founders confirming earlier mtDNA results. Early dog dispersal is tightly coupled to human history with the dog brought along as a cultural item. We have for the first time investigated the dog dispersal into Polynesia and Australia and our data can be used as evidence for a more complex settlement of Polynesia than earlier indicated from archaeological and linguistic studies. Analysis of Y-chromosome SNPs in Australian dingoes confirms earlier mtDNA genetic studies that the dingo is part of the domestic dog phylogeny and was founded from a small population of domestic dogs. We have also for the first time investigated the dog population on Madagascar and our data strongly indicates a mainland African origin for the Madagascan dogs. Finally, we have investigated the American dog population sampled from throughout the continent and also for the first time included putative indigenous breed dogs such as Chihuahua and Pero Sín Pelo del Peru, and the free-ranging Carolina dogs from southern USA. Our data clearly indicates a primarily Old World origin for the indigenous breed dogs and also for the free-ranging Carolina dogs in USA. We can also for the first time present evidence for continuity between the ancient and extant dog population with e.g. exclusive sharing of a haplotype between a modern sample of Chihuahua and an ancient Mexican sample. / QC 20120510
338

A quantitative survey of aberrant chromosome behavior in the Rhoeo spathacea population at Ball State University

Robinson, Sandra Kay 03 June 2011 (has links)
Using the acetocarmine squash technique to examine pollen mother cells, the meiotic chromosome behavior of each of 16 Rhoeo spathacea plants housed in the Ball State University greenhouse was analyzed with respect to the frequencies of several types of atnormalities and documented with suitable photomicrographs. Among the aberrant types of chromosome behavior resulting from multiple translocations among the 12 chromosomes of each plant were the followings ring and chain formation of chromosomes at diakinesis and metaphase I, adjacent versus alternate chromosome alignment patterns at metaphse I and anaphase I, various abnormal anaphase I and telophase I disjunction patterns, and the presence of excluded chromosomes and micronuclei at telophase I. As a further consequence of the multiple translocations and abnormal chromosome disjunction, many of the pollen grains formed by meiosis were found to be defective and non-viable.Ball State UniversityMuncie, IN 47306
339

Chromosome cytology of variegated and anthocyaninless varieties of Rhoeo Spgthacea (Swartz) Stearn

Baker, Robert F. 03 June 2011 (has links)
Pollen mother cells from each of eleven Rhoeo specimen plants housed in the Ball State University greenhouse were analyzed for meiotic chromosome behavior and were found to display multiple reciprocal translocations characteristic of the species. Seven of the eleven plants are classified as Rhoeo soathacea var. variegata, while the remaining four plants are classified as Rhoeo spathacea var. concolor. Using the acetocarmine squash technique, 5362 pollen mother cells from the eleven Rhoeo specimen plants were examined and photomicrographs of representative pollen mother cells were used to document data reported. Among the types of aberrant chromosome behavior resulting from multiple reciprocal translocations in the twelve chromosomes of Rhoeo were ring and chain formation at diakinesis, alternate versus adjacent chromosome alignment at metaphase I, atypical segregation patterns at anaphase I and the presence of micronuclei or chromosomes excluded from the daughter nuclei at telophase I. Many prophase I/metaphase I chromosome configurations and a number of anaphase I segregation patterns not previously reported in the literature were observed in this study. As a consequence of aberrant chromosome behavior many of the pollen grains formed during meiosis were defective and non-viable.Ball State UniversityMuncie, IN 47306
340

The Concordance between Immunohistochemical Staining and Silver In Situ Hybridization for HER2 Status in Breast Cancer Tissue Samples

Kardeby, Caroline January 2011 (has links)
The human epidermal growth factor receptor-2 (HER2) protein has been associated with breast cancer progression and the HER2 status can be used to determine the type of treatment for each breast cancer patient. The purpose of this study was to examine the HER2 protein and gene statuses in breast cancer tissue samples using two methods and analyze the concordance between them. Ten paraffin-embedded, formaldehyde-fixed breast cancer tissue samples from the Biobank at the Department of Pathology and Cytology at Sundsvall Hospital were analyzed in this study. All samples were from women born between 1931 and 1976. The methods used were immunohistochemistry (IHC) to visualise the HER2 protein and silver in situ hybridization (SISH) to detect gene amplification. The IHC staining method is an indirect detection of the HER2 protein using antibodies. The SISH method used in this study is a Dual ISH which detects both the HER2 gene and the centromere region of Chromosome 17 on the same tissue slide. A HER2 gene/Chromosome 17 ratio was calculated according to the manufacturer’s instructions. This ratio was used to determine HER2 gene status. Out of ten samples, seven were positive with IHC and three were negative. The results from the SISH staining exposed a gene amplification in three of the IHC positive samples, while seven samples did not contain any amplified HER2 genes. The conclusion was that the concordance between IHC and SISH for HER2 was 60 percent.

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