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Přínos molekulárně genetických a cytogenetických analýz k diagnostice a predikci léčebné odpovědi u pacientů s non-Hodgkinskými lymfomy / The role of molecular genetic and cytogenetic analyses in the diagnosis and prediction of treatment response in patients with non-Hodgkin lymphomasBerková, Adéla January 2014 (has links)
Malignant lymphoproliferative disorders include highly heterogeneous entities, i.e. lymphomas (Non-Hodgkin - NHL, as well Hodgkin's lymphoma), lymphoid leukemias, multiple myeloma and others. As currently many chromosomal aberrations with diagnostic and prognostic significance are known, molecular cytogenetic analyses of tumor cell genome has become a substantial examination also in lymphoproliferative disorders. This thesis focuses primarily on chronic lymphocytic leukemia (CLL), which is one of the mature B-cell neoplasms and represents the most common type of leukemia. We analyzed four most frequently found aberrations (13q14 deletion, ATM and TP53 gene deletion, and trisomy 12) by fluorescence in situ hybridization (FISH) and also IgH gene aberrations in some patients. We compared the findings with other factors and clinical characteristics. This work shows that the conventional G-banding is analysis relatively little relevant. FISH was more effective in detecting aberrations in CLL. Although none of the four aforementioned changes is specific to CLL, the prognostic impact is significant, particularly that of TP53 deletion. Next, detection of some IgH gene translocations is essential in differential diagnosis of CLL and other NHL (follicular, mantle cell, diffuse large B cell, Burkitt's...
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Přínos molekulárně genetických a cytogenetických analýz k diagnostice a predikci léčebné odpovědi u pacientů s non-Hodgkinskými lymfomy / The role of molecular genetic and cytogenetic analyses in the diagnosis and prediction of treatment response in patients with non-Hodgkin lymphomasBerková, Adéla January 2014 (has links)
Malignant lymphoproliferative disorders include highly heterogeneous entities, i.e. lymphomas (Non-Hodgkin - NHL, as well Hodgkin's lymphoma), lymphoid leukemias, multiple myeloma and others. As currently many chromosomal aberrations with diagnostic and prognostic significance are known, molecular cytogenetic analyses of tumor cell genome has become a substantial examination also in lymphoproliferative disorders. This thesis focuses primarily on chronic lymphocytic leukemia (CLL), which is one of the mature B-cell neoplasms and represents the most common type of leukemia. We analyzed four most frequently found aberrations (13q14 deletion, ATM and TP53 gene deletion, and trisomy 12) by fluorescence in situ hybridization (FISH) and also IgH gene aberrations in some patients. We compared the findings with other factors and clinical characteristics. This work shows that the conventional G-banding is analysis relatively little relevant. FISH was more effective in detecting aberrations in CLL. Although none of the four aforementioned changes is specific to CLL, the prognostic impact is significant, particularly that of TP53 deletion. Next, detection of some IgH gene translocations is essential in differential diagnosis of CLL and other NHL (follicular, mantle cell, diffuse large B cell, Burkitt's...
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Ocular accommodation control and adaptive optics. The development of monocular and binocular adaptive optics instrumentation for the study of accommodation and convergence, and study of the monocular accommodative response to rapid changes in dioptric stimuli.Curd, Alistair P. January 2014 (has links)
The relationship between accommodation and myopia has been under investigation for many years, and the effort to understand it is ongoing.
In this thesis, an introduction to the state of myopia research is given first, with particular reference to studies of accommodation and higher-order ocular aberrations, which feature in the subsequent chapters.
Following a brief introduction to the general technique of aberrometry and visual stimulus control using adaptive optics, the development of a monocular adaptive optics instrument for this purpose is described. The instrument is used to vary a dioptric stimulus and record the accommodation response in pilot studies and a detailed experiment, which has also been published elsewhere. It is found, among other things, that accommodation can respond to more than one different input level during its latency period, and that such inputs can be stored until components of the accommodation control system are free to process them. Indications of a minimum halting time for accommodation, of around 0.6 s, are presented.
In later chapters, the development and testing of a new, binocular adaptive optics apparatus will be found. As well as binocular aberrometry and adaptive optics control of stimulus aberrations, this instrument displaces images to allow for and stimulate ocular convergence in binocular accommodation experiments. It is the first instrument in the world with its combined functionalities.
Finally, the contribution of this thesis is summarised, and further instrumentation development and experiments are put forward for the continuation of this branch of accommodation and myopia research.
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Mean curvature mapping: application in laser refractive surgeryTang, Maolong 12 October 2004 (has links)
No description available.
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Visual Optics: AstigmatismCox, Michael J. January 2010 (has links)
No
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Effect of temporal location of correction of monochromatic aberrations on the dynamic accommodation responseHampson, Karen M., Chin, Sem Sem, Mallen, Edward A.H. January 2010 (has links)
No / Dynamic correction of monochromatic aberrations of the eye is known to affect the accommodation response to a step change in stimulus vergence. We used an adaptive optics system to determine how the temporal location of the correction affects the response. The system consists of a Shack-Hartmann sensor sampling at 20 Hz and a 37-actuator piezoelectric deformable mirror. An extra sensing channel allows for an independent measure of the accommodation level of the eye. The accommodation response of four subjects was measured during a +/- 0.5 D step change in stimulus vergence whilst aberrations were corrected at various time locations. We found that continued correction of aberrations after the step change decreased the gain for disaccommodation, but increased the gain for accommodation. These results could be explained based on the initial lag of accommodation to the stimulus and changes in the level of aberrations before and after the stimulus step change. Future considerations for investigations of the effect of monochromatic aberrations on the dynamic accommodation response are discussed.
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Développement d'une nouvelle méthode de caryotypage chez le porcPoisson, William 13 December 2023 (has links)
Les chromosomes sont étudiés dans plusieurs domaines de la génétique. L'architecture chromosomique permet notamment de mieux comprendre l'évolution des espèces ou de documenter l'impact d'un réarrangement sur l'expression des phénotypes. Grâce aux analyses cytogénétiques, des anomalies chromosomiques ont été répertoriées et associées à une baisse de fertilité chez plusieurs espèces d'élevage dont le porc. La présence de ces aberrations au sein des verrats reproducteurs, dont la semence est largement disséminée, est problématique puisqu'elle peut induire des pertes économiques estimées à plus de 4,6M$ au Canada. Il semble donc important d'effectuer une analyse chromosomique rigoureuse avant leur entrée en service pour l'insémination. Plusieurs méthodes ont été développées pour effectuer des analyses cytogénétiques, mais peu offrent à la fois un faible coût, une bonne résolution et une simplicité d'analyse. Dans la dernière décennie, l'hybridation in situ en fluorescence utilisant des oligonucléotides a gagné en popularité. La première hypothèse présentée au sein de cet ouvrage est qu'il est possible d'utiliser ce type de marquage pour générer un patron de bandes fluorescentes afin d'évaluer l'intégrité des chromosomes tout en alliant simplicité, précision et faible coût d'analyse. Cette hypothèse a été validée au chapitre 2 par le développement d'une méthode qui a permis l'identification de cinq réarrangements chromosomiques grâce à 96 bandes fluorescentes marquant spécifiquement l'ensemble des chromosomes porcins. Une deuxième hypothèse soulevée est qu'il est possible d'adapter cette méthode pour assembler un génome au niveau chromosomique, pour détecter des erreurs d'assemblage et pour étudier l'évolution chromosomique entre espèces apparentées. Le chapitre 3 valide cette hypothèse par l'assemblage de 78% du génome de Rangifer tarandus au niveau chromosomique, la correction de six échafaudages génomiques et l'observation de réarrangements chromosomiques dans le processus évolutif de certains cervidés et bovidés. / Chromosomes are studied in several fields of genetics. The chromosomal architecture makes it possible to better understand the evolution of species or to document the impact of a rearrangement on the expression of phenotypes. Thanks to cytogenetic analyses, chromosomal abnormalities have been identified and associated with a decline in fertility in several livestock species, including pigs. The presence of these aberrations in nucleus herd boars, whose semen is widely disseminated, is problematic since it can induce economic losses estimated at more than $4.6M in Canada. It therefore seems important to carry out a rigorous chromosomal analysis before they enter service for insemination. Several methods have been developed to perform cytogenetic analyses, but few offer both low cost, good resolution and simplicity of analysis. In the last decade, fluorescence in situ hybridization using oligonucleotides has gained popularity. The first hypothesis presented in this work is that it is possible to use this type of labelling to generate a pattern of fluorescent bands in order to assess the integrity of chromosomes while combining simplicity, precision and low cost of analysis. This hypothesis was validated in chapter 2 by the development of a method which allowed the identification of five chromosomal rearrangements thanks to 96 fluorescent bands labelling specifically all the porcine chromosomes. A second hypothesis raised is that it is possible to adapt this method to assemble a genome build at the chromosome level, to detect assembly errors and to study chromosomal evolution between related species. Chapter 3 demonstrates the veracity of this hypothesis by the assembly of 78% of the Rangifer tarandus genome at the chromosome level, the correction of six genomic scaffolds and the observation of chromosomal rearrangements in the evolutionary process of certain cervids and bovids.
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A Monte-Carlo optical workbench for radiometric imaging system designWalkup, Michael D. 29 August 2008 (has links)
The objective of this research is to study the field of optical engineering and to combine this knowledge with radiation heat transfer analysis to create a radiometric imaging design tool. In particular, the tool is aimed at design of reflective radiometric imaging telescopes, capable of highly accurate heat flux measurements, to be used in space-borne satellite applications. A concise reference guide is provided to aid in the design of somewhat generic reflective radiometric imaging systems. Also developed is a Monte-Carlo virtual optical workbench that models one- and two-mirror reflective radiometric telescopes. The virtual optical workbench is capable of performing optical analyses and generating radiometric images based on temperatures of scene components and telescope structures. The workbench model allows simulation of surfaces with different absorptivities, along with simulation of surfaces that have diffuse as well as specular components of reflectivity. Results from the virtual optical workbench are presented to show the myriad of functions incorporated in this powerful new tool. / Master of Science
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Thermally Deformable Mirrors : a new Adaptive Optics scheme for Advanced Gravitational Wave Interferometers / Miroirs Thermiquement Déformables : un nouveau schéma d’Optique Adaptative pour les Interféromètres Gravitationnels AvancésKasprzack, Marie 26 September 2014 (has links)
L’objectif de la thèse est de développer une nouvelle technique d’optique adaptive pour les interferomètres gravitationels avancés, basée sur un nouveau type de miroir pour le faisceau d’injection de l’interferomètre. Le miroir déformable, basé sur une actuation thermique, doit etre un outil compatible ultra-vide, qui fonctionne sans bruit électronique ou mécanique, bon marché et permettre la correction des modes d’ordre supérieurs afin d’améliorer le matching des faisceaux de haute puissance dans les cavités laser du détecteur sous ultra-vide. Un montage experimental de caractérisation du miroir déformable a été mis en place afin d’effectuer les tests de validation du premier prototype sous air. L’élaboration d’une procédure de caractérisation des propriétés du miroir et d’une boucle de controle a permis de développer une approche efficace pour déterminer les possibilités et les limites du miroir. Nous avons ainsi pu faire la démonstration de sa capacite a corriger les aberrations de phase d’un faisceau laser infrarouge a différentes fréquences spatiales. Nous avons également démontré que le miroir vérifie les performances de stabilité, de reproductibilité et de linearité attendues. Nous avons ensuite validé l’amélioration du mode matching d’un faisceau laser sur une cavité de réference par le miroir thermiquement déformable / In this thesis we develop a new technique of adaptive optics for the Advanced Gravitational Interferometers, based on a new type of deformable mirror for the injection beam of the interferometer. This deformable mirror, based on a thermal actuation, has to be a high vacuum compatible and low-cost device, that is working without any electronic or mechanic noise. It has to allow the correction of high order modes to improve the matching of high power laser beams in the interferometer.An experimental setup has been made to characterize the first prototype on air. An efficient process and a control loop have allowed to determine the possibilities and limits of the device. We have demonstrated its ability to correct high order modes of an infrared laser beam. Afterwards, we have validated the improvement of mode matching into a fixed cavity.
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Une nouvelle méthode de décomposition polynomiale d’un front d’onde oculaire / A new polynomial decomposition method for ocular wavefrontGatinel, Damien 12 July 2017 (has links)
Les défaut de la vision sont analysés et classés à partir des caractéristiques mathématiques du front d’onde de l’oeil considéré. Après avoir présenté la méthode actuelle basée sur la décomposition du front d’onde dans la base orthonormale de Zernike ainsi que certaines de ses limitations, on propose ici une nouvelle base de décomposition. Celle-ci repose sur l’utilisation del’espace des fronts d’onde polynomiaux de valuation supérieure ou égale à L + 1 (où L est un entier naturel) et permet de décomposer de manière unique un front d’onde polynomial en la somme d’un front d’onde polynomial de bas degré (inférieur ou égal à L) et un front d’onde polynomial de haute valuation (supérieure ou égal à L + 1). En choisissant L = 2, une nouvelle décomposition est obtenue, appelée D2V3, où le front d’onde polynomial de haut degré ne comporte pas de termes de degré radial inférieur ou égal à deux. Cette approche permet de dissocier parfaitement les aberrations optiques corrigibles ou non par le port de lunettes. Différents cas cliniques présentés dans la dernière section permettent de mettre en évidence l’intérêt de cette nouvelle base de décomposition. / The eye vision defaults are analyzed and classified by studyingthe corresponding eye wavefront. After presenting the orthogonal basis, called the Zernike basis, that is currently used for the medical diagnosis, a new decomposition basis is built. It is based on the use of the space of polynomials of valuation greater or equal to L+1 (for L a natural integer). It allows to uniquely decompose a polynomial wavefront into the sum of a polynomial of low degree (lesser or equal to L) and a polynomial of high valuation (greater or equal to L +1). By choosing L = 2, a new decomposition, called D2V3, is obtained where the polynomial wavefront of high degree does not include terms of radial degree lesser or equal to 2. In particular, it allows to quantify perfectly the aberrations that can be corrected by eyeglasses or not. Various clinical examples clearly show the interest of this new basis compared to a diagnosis based on the Zernike decomposition.
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