Search for dissertations about: "aberration"

Showing result 1 - 5 of 87 swedish dissertations containing the word aberration.

  2. 1. Transverse Chromatic Aberration and Vision: Quantification and Impact across the Visual Field

    Author : Simon Winter; Linda Lundström; Stephen Burns; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; transverse chromatic aberration; lateral chromatic aberration; visual optics; peripheral vision; central vision; dispersion; ophthalmic optics and devices; optical effects on vision; retinal imaging; myopia; human eye; Fysik; Physics;

    Abstract : The eye is our window to the world. Human vision has therefore been extensively studied over the years. However, in-depth studies are often either limited to our central visual field, or, when extended to the periphery, only correct optical errors related to a narrow spectrum of light. READ MORE

  4. 2. Image Analysis Techniques for Segmentation, Classification and Presentation of High-Resolution Prometaphase Chromosome

    Author : Stefan Nivall; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aberration; segmentation; digital image analysis; high-resolution CCD camera; classification; prometaphase; chromosome; database;

    Abstract : The extraction, analysis, and presentation of integrated optical density (IOD) profiles from banded prometaphase chromosome material is an increasingly important clinical method for the detection and analysis of structural aberrations. Particular translocations, duplications, or deletions of genetic material have been shown to be implicated in specific mental or physical disorders. READ MORE

  5. 3. MULTIFOCAL SPHERICAL FISH LENSES

    Author : Yakir Gagnon; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Multifocal Lens; Adaptation; Dispersion; Spherical lens; Model; Fish; Ray-trace; Longitudinal Chromatic Aberration; Longitudinal Spherical Aberration; Modulation Transfer Function; Point Spread Function; Refractive Index Gradient;

    Abstract : Vision is an important source of information for many animals. The lens plays a central role in the visual pathway and hence the ecology of these animals. Fish have spherically shaped crystalline lenses that contain a gradient of refractive index. Like all refracting elements, lens performance depends on the wavelength of the refracted light. READ MORE

  6. 4. Manipulation of Ocular Aberrations in Myopes

    Author : Baskar Theagarayan; Jörgen Gustafsson; Frank Schaeffel; Linnéuniversitetet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Myopia; Spherical aberration; Accommodation; Contact lens; Visual acuity; Peripheral aberrations; Optometry; Optometri; Optometry; Optometri;

    Abstract : Myopia is a major cause of vision loss throughout the world. High myopia is associated with severe eye diseases like maculopathy, retinal detachment and glaucoma. The prevalence of myopia is increasing, and varies by country and by ethnic group. In some Asian populations the prevalence is 70%-80%. READ MORE

  7. 5. Genetic and epigenetic characterization of pediatric high hyperdiploid acute lymphoblastic leukemia

    Author : Josef Davidsson; Avdelningen för klinisk genetik; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; high hyperdiploid ALL; children; chromosome aberration; methylation profiling; array CGH; relapse; SNP array; clonal relationship; dup 1q ;

    Abstract : The aim of this thesis was to analyze the genetic and epigenetic characteristics of pediatric high hyperdiploid acute lymphoblastic leukemia (HeH ALL), the most common type of childhood malignancy. The three original articles presented in this thesis have addressed three major questions regarding HeH ALL: what are the genetic characteristics of the most common structural abnormality – dup(1q)? Are aberrant methylation patterns involved in leukemogenesis? How do diagnostic and relapse samples relate to each other genetically? In article I we found that the proximal breakpoints of dup(1q)-positive Burkitt lymphomas (BL) and pediatric HeH ALLs cluster close to the centromere, suggesting this region to be breakprone, and that five genes on 1q were significantly overexpressed and thus potentially pathogenetically important. READ MORE