Made available in DSpace on 2014-10-09T12:34:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:51Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:34:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:51Z (GMT). No. of bitstreams: 0 / Este trabalho desenvolve uma metodologia para a automação da análise morfológica de imagens de cromossomos humanos irradiados no reator nuclear IEA-R1 (localizado no Instituto de Pesquisas Energéticas e Nucleares, IPEN, em São Paulo, Brasil) e, portanto, sujeitos a aberrações morfológicas. Esta metodologia se propõe a auxiliar na identificação, caracterização e classificação de cromossomos pelo profissional citogeneticista. O desenvolvimento da metodologia inclui a elaboração de um aplicativo baseado em técnicas de inteligência artificial utilizando Lógica Fuzzy e técnicas de processamento de imagens. O aplicativo desenvolvido foi denominado de CHRIMAN e é composto de módulos que contêm etapas metodológicas que suprem aspectos importantes para a obtenção de uma análise automatizada. A primeira etapa é a padronização dos procedimentos de aquisição das imagens digitais bidimensionais de metáfases através do acoplamento de uma câmera fotográfica digital comercial comum à ocular do microscópio utilizado na análise metafásica convencional. A segunda etapa é relativa ao tratamento das imagens obtidas através da aplicação de filtros digitais, armazenamento e organização das informações tanto do conteúdo da imagem em si, como das características extraídas e selecionadas, para posterior utilização nos algoritmos de reconhecimento de padrões. A terceira etapa consiste na utilização do banco de imagens digitalizadas e informações extraídas e armazenadas para a identificação dos cromossomos, sua caracterização, contagem e posterior classificação. O acerto no reconhecimento das imagens cromossômicas é de 93,9%. Esta classificação é baseada nos padrões encontrados classicamente em Buckton [1973], e possibilita o auxílio ao geneticista no procedimento de análise dos cromossomos com diminuição do tempo de análise e criando condições para a inclusão deste método num sistema mais amplo de avaliação de danos causados às células pela exposição à radiação ionizante. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

nÃo hà / O elevado consumo de pesticidas no Brasil e no mundo tem levado grupos de pesquisadores a relacionar essa exposiÃÃo a possÃveis danos genÃticos e agravos a saÃde do trabalhador rural. Estudos revelam que o cÃncer à considerado doenÃa genÃtica, vez que resulta do acÃmulo de mutaÃÃes em genes comprometidos com o controle da proliferaÃÃo e da diferenciaÃÃo celular ou de mutaÃÃes em genes envolvidos com os mecanismos de reparo do DNA. O objetivo dessa estudo foi realizar um biomonitoramento genÃtico em indivÃduos expostos ocupacionalmente a pesticidas avaliando a ocorrÃncias de danos cromossÃmicos, atravÃs do teste do MicronÃcleo em cÃlulas esfoliadas da mucosa bucal, teste Cometa e teste de AberraÃÃes CromossÃmicas em linfÃcitos de sangue perifÃrico. Como tambÃm alteraÃÃes hematolÃgicas e hepÃticas. A populaÃÃo estudada incluiu 32 agricultores moradores do povoado Vila Bessa, ConceiÃÃo do JacuÃpe, Bahia, expostos ocupacionalmente a pesticidas e 30 indivÃduos controle, sem historia de exposiÃÃo a pesticidas. O material para anÃlise do teste do micronÃcleo foi coletado por raspagem da mucosa bucal com escova cytobrush, confeccionado um esfregaÃo e posteriormente fixado em soluÃÃo de metanol/Ãcido acÃtico (3:1) e corados pelo mÃtodo FeÃlgen/Fast Green, as lÃminas foram analisadas em teste cego sob microscopia Ãptica em um mÃnimo de 1000 cÃlulas/indivÃduo. Para realizaÃÃo do teste Cometa e de AberraÃÃes, cromossÃmicas e das alteraÃÃes hematolÃgicas e hepÃticas foram coletadas 10 mL de sangue perifÃrico. O teste Cometa foi executado de acordo com a metodologia descrita por por Singh et al. (1988), foram contados 100 cometas por lÃmina e classificados, por anÃlise visual, dentre cinco categorias de danos (0, 1, 2, 3 e 4), e calculado o Ãndice e a FreqÃÃncia de dano. O teste de AberraÃÃes CromossÃmicas foi realizada atravÃs de culturas de linfÃcitos e obtenÃÃo de metÃfases pela interrupÃÃo da citocinese das cÃlulas. Foram analisados o hemograma, e as transaminases TGO, TGP E GGT que foram processados pelo laboratÃrio de anÃlise bioquÃmica de Escola Bahiana de Medicina e SaÃde PÃblica. NÃo houve diferenÃa significativa na ocorrÃncia de micronÃcleos entre os grupos avaliados (p = 0,163), mas alteraÃÃes nucleares indicativos de apoptose e necrose foram encontradas significantemente no grupo exposto a pesticidas (p = 0,001), indicando que uma maior injÃria celular do que simplesmente uma resposta a diferenciaÃÃo e maturaÃÃo do epitÃlio. AberraÃÃes CromossÃmicas numÃricas (3,3%) foi encontrada significantivamente para o grupo exposto (p = 0,001), foram encontrados danos ao DNA avaliados pelo teste Cometa no escore 1 (p< 0.001) no grupo exposto; alÃm do Ãndice de Dano cromossÃmico com mÃdia  SEM 4.032  0.3336 para o grupo controle e mÃdia  SEM 41.05  3.227 para o grupo exposto a pesticida (p<0,0001); e FreqÃÃncia de Dano: mÃdia  SEM grupo controle 4.081  0.3667 e mÃdia  SEM grupo exposto a pesticida 38.44  2.664, com diferenÃas significativas para o grupo exposto (p<0,0001). Os indivÃduos pesquisados estÃo expostos ao glifosato e ao paration-metÃlico, ambos tÃxicos para o organismo humano, e apresentavam-se anÃmicos (p=0,004) e com leucopenia (p < 0,001), porÃm sem alteraÃÃes nas avaliaÃÃes hepÃticas. ConcluÃmos que esses indivÃduos estÃo expostos a agentes potencialmente genotÃxicos, alÃm de apresentarem alteraÃÃes hematolÃgicas, e que a persistÃncia desse contato com os pesticidas poderà levar a desencadeamento dos fenÃmenos envolvidos na iniciaÃÃo e promoÃÃo do cÃncer. / The high consumption of pesticides in Brazil and all over the world have lead researches to relate this exposition to possible genetic and health damages in rural workers. Studies reveal that cancer is considered a genetic disease, once it results of the mutation accrual in genes involved with control of proliferation and cellular differentiation or mutations in genes involved with the DNA repair. The aim of this study was realize a genetic biomonitoring in individuals occupationally exposed to pesticides evaluating the occurrence of chromosomal damages, by the Micronucleus assay in exfoliated cells of buccal mucosa, Comet assay and Chromosome Aberration assay in peripheral blood lymphocytes. Hematologic and hepatic alterations were also evaluated. The studied population included 32 agriculturists living in the village of Vila Bessa, ConceiÃÃo do JacuÃpe, Bahia, occupationally exposed to pesticides, and 30 control individuals, with no history of pesticides exposition. For the micronucleus assay, the material was collected by scaling buccal mucosa with a cytobrush, the smear was made and then fixed in methanol/acetic acid solution (3:1) and colored by FeÃlgen/Fast Green Method, slides were analyzed in blind test by optic microscopy in a minimum of 1000 cells/individual. To realize the assay of Comet and Aberration, Chromosomal and hematologic and hepatic alterations, were collected 10 mL of peripheral blood. Comet test was made according the methodology described by Singh et al. (1988), were counted 100 comet by slides and classified, by visual analyses, into five categories of damages (0, 1, 2, 3 e 4), and then calculated the index and frequency of damage. Chromosome Aberration test was realized with a lymphocytes culture and obtaining of metaphases by interrupting the cells cytokinesis. The hemogram and the transaminases TGO, TGP and GGT were analyzed; those were processed by the biochemical analyses laboratory of Escola Bahiana de Medicina e SaÃde PÃblica. That wasnÂt statistical difference in the occurrence of micronucleus among the evaluated groups (p = 0.163), but nuclear alterations, indicative of apoptosis and necrosis, were significantly found in the pesticide exposed group (p = 0.001), indicating a major cellular injury than a simple answer to epitheliumÂs differentiation and maturation. Numeric Chromosome Aberrations (3.3%) were significantly found in the exposed group (p = 0.001), were found DNA damages evaluated by the Comet assay in score 1 (p<0.001) in the exposed group; as also index of chromosomal damage with media  SEM 4.032  0.3336 to the control group and media  41.05  3.227 to the pesticide exposed group (p<0.0001); and frequency of damage: media  SEM control group 4.081  0.3667 and media  SEM pesticide exposed group 38.44  2.664, with significant differences in the exposed group (p<0.0001). The studied individuals are exposed to glifosate and methyl parathion, both toxic to the human organism, and were anemics (p=0.004) and with leukopenia (p<0.001), however with no alterations in hepatic evaluations. We conclude that these individuals are exposed to potentially genotoxic agents, besides present hematologic alterations, and that the persistence of this contact with the pesticides can trigger to phenomenonâs involved with cancer initiation and promotion.

An edge response characterization technique to predict the ITF of an interferometer using non- interferometric measurements has been shown to be effective. This technique eliminates the need for phase objects to be used in the characterization process. Using coherent imaging with an irradiance sensitive detector and an irradiance step as a characterization artifact to determine an interferometer's ITF was proven viable for diffraction limited, defocused, astigmatic, and spherically aberrated systems. Simulations and collected data demonstrated agreement between the interferometric edge response characterization technique results and coherent imaging edge response characterization technique results. The effect that aberrations have on ITF curves has been investigated in this thesis and an understanding of the system behavior under aberrated conditions was investigated.

The principal work in this thesis describes the investigation of the impact that alterations to ocular aberrations following refractive surgery have on the accommodative mechanism. A series of prospective studies were conducted with healthy adults (n=36) that had chosen to undergo refractive surgery at Manchester Royal Eye Hospital. A variety of monocular accommodative functions were assessed prior to surgery and then at one and three months following surgery on the same cohort of patients. Accommodative functions included amplitude of accommodation, accommodative facility (at 6m and 0.4m) including positive and negative response times, and accommodative stimulus-response functions. Dynamic accommodation responses were examined in a subgroup (n=10) at three months following refractive surgery and compared to an age-matched emmetropic control group (n=10) to evaluate differences in latency, amplitude, time constant and peak velocity of accommodation and disaccommodation. During the studies, ocular aberrations were concurrently measured to determine whether alterations to aberrations could help explain any observed changes in accommodative functions. Evaluation of visual, refractive and questionnaire outcome measures indicated that the patient cohort underwent successful surgery. Following surgery, significant alterations to a number of accommodative functions were discovered. Mean subjective ocular amplitude of accommodation increased by approximately 0.50D (p<0.05), mean stimulus-response function gradient decreased by approximately 10% (p<0.05) and distance facility rate increased by approximately 2-3 cycles/minute (p<0.05). Significant correlation was found between the change in accommodative stimulus-response function gradient, and the change in spherical aberration following surgery (p<0.05). Significant differences were also found in the parameters of accommodative dynamics, although some of these factors may be explained by refractive error differences between the refractive surgery patients (pre-operative myopes) and the emmetropic control group. The results suggest that alterations to aberrations following refractive surgery may be capable of influencing elements of the accommodation response. Additional studies were conducted to investigate the changes in aberrations during accommodation (n=31 subjects), and explore the contribution of the tear film (n=19 subjects) to higher order aberrations in eyes that have undergone refractive surgery. The results suggested that the rate of change in aberrations during accommodation is not affected by refractive surgery, but that the pattern of aberrations induced by post-blink tear film changes may differ in patients that have undergone refractive surgery. A further study is presented which investigated the form of the accommodative stimulus-response function to grating target of different spatial frequencies in groups of myopic (n=10) and emmetropic (n=10) participants recruited from among the staff and students at The University of Manchester. Both refractive groups appeared to show similar accommodative behavior, however the dominant feature of the data in both groups was between subject variation.

During the screening process 5,20 8 X chromosomes of -Drosophila melanogaster were analyzed for the presence of temperature-sensitive (ts) lethal mutations (i.e. mutants which die at 29°C but are viable at 22°C) in short proximal and distal segments of the chromosome. Seven ts and 16 non-ts lethals were recovered in both regions combined. A new class of mutations (class-3), which failed to survive at 29°C with either proximal or distal duplication and showed ts lethality with one, was found and extensively analyzed. These mutants were initially interpreted to be dominant ts's, although the heterozygotes of each mutant showed this not to be so. It was decided that these might more probably be chromosomes carrying a lethal mutation covered by the duplication, and a ts lethal mapping elsewhere. By masking the non-conditional lethal with a duplication, developmental studies of the ts mutant were made. The temperature-sensitive period (TSP) and lethal phase (LP) were characterized for each. All TSP’s spanned the early pupal interval, though an individual TSP might extend to either side of this interval. The pattern of temperature-sensitivity of C3-3 suggested that once formed at permissive temperature, its product was not affected by 29°C. The experiments suggest that the temperature-sensitive process occurs at transcription or translation. A lethal allele of the dor locus was recovered, and, in analysis of this mutant with other dor alleles and several variegating duplications, dor itself was found to be a ts lethal. "Warped" wing, a new phenotype of the dor locus which occurred only with the variegating duplications, was described. This paper further describes a method for developmental analysis of non-ts lethal mutations, involving the use of variegating rearrangements. / Science, Faculty of / Zoology, Department of / Graduate

The present study was initiated with the view of achieving two goals: 1) to establish a suitable genetic assay system for measuring the frequency of spontaneous and induced structural and numerical aberrations of autosomes during meiosis in females and 2) to provide a better understanding of the mechanisms responsible for the production of the aberrant classes recovered. By selective exclusion of all regular meiotic products this system enabled the recovery of large numbers of aberrant products. The multiplier system served as an internal dosimeter and provided an estimate of the population size from which the aberrancies arose which in turn provided a measure of the frequencies of each event. The four different classes of exceptional meiotic products were named according to the source or the structural nature of the chromosomes: reductional nondisjunction as "matroclinous"; equational nondisjunction as "equationals"; loss of chromosome 2 as "patroclinous"; and the attachment of homologous arms as "compounds". The results suggest that two main factors affect the recovery of induced aberrations: of most importance is isosequentiality and of lesser importance is genetic background. The three classes of simultaneously recovered progeny (excluding equational nondisjunctions) arise from a common mechanism of induction; a mechanism which also accounts for free arm formation. The location of the breaks, the position of the chromatids and the method of reconstitution determine the type of aberration produced. The reconstitution of these breaks in aberrant ways are referred to as interchanges. Furthermore, it would appear that the reconstitutions are restricted in that euchromatic breaks attach to euchromatic breaks and heterochromatic to heterochromatic. Interchanges resulting from breaks on opposite sides of the centromeres of homologues result in the formation of non-sister compound chromosomes and from breaks on opposite sides of the centromeres of sister chromatids result in the formation of sister compound chromosomes. The interchange, if between heterologues, could lead to the nondisjunction of a pair of chromosomes and be recovered, as in the present study, as matroclinous progeny. The reciprocal product of the interchange between heterologues would produce an equal number of nullo eggs observed as patroclinous progeny, but if the dyad so formed is heteromorphic, i.e. chromatids of different length, it would result in the greater recovery of patroclinous progeny because of the preferential inclusion of the shorter chromatid. The evidence for interchange mediated aberrations is provided by the recovery of free arms of chromosome 2. Experimental support for these events is provided by the unequivocal identification of the centromeres involved, which, as in this study, is made possible through the use of metacentric autosomes. / Science, Faculty of / Zoology, Department of / Graduate

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Un défi important pour les futurs collisionneurs linéaires électron-positron est de pouvoir focaliser le faisceau à des tailles transverses de l’ordre du nanomètre au point d’interaction (IP), permettant d’atteindre la luminosité de conception. Le système délivrant les faisceaux d’e- et de e + de la sortie du Linac principal vers le point d’interaction, le Beam Delivery System (BDS), réalise les fonctions critiques requises pour atteindre l’objectif de luminosité, tel que la collimation et la focalisation du faisceau. Le faisceau est focalisé par le système de focalisation finale (FFS) tout en corrigeant les aberrations d’ordre supérieur propagées le long du système. Les effets chromatiques contribuant à l’élargissement de la taille du faisceau, sont amplifiés par la force de focalisation des deux derniers quadripôles QF1 et QD0, ou doublet final (FD), et par la longueur de la distance focale finale L* entre QD0 et l’IP. L’approche de correction de la chromaticité retenue pour les deux grands projets actuels de collisionneurs linéaires, CLIC et ILC, est fondée sur la correction locale de la chromaticité générée par le doublet final. Ce schéma est actuellement testé à l’ATF2 au KEK (Japon). Ce travail de thèse se concentre sur les problématiques liées au système de focalisation finale du projet CLIC re-optimisé avec un plus long L*, dans le cadre de la simplification de l’interface machine-détecteur (MDI), ainsi que sur le travail expérimental conduit à l’ATF2 pour l’optimisation et l’étude des optiques du système de focalisation finale à ultra-bas β* incluant les tout premiers est in situ des octupôles à l’ATF2. / The future machines considered to carry out high precision physics in the TeV energy regime are electron-positron (e+e−) linear colliders. Future linear colliders feature nanometer beam spot sizes at the Interaction Point. The Beam Delivery System (BDS) transports the e + and e− beams from the exit of the linacs to the IP by performing the critical functions required to meet the CLIC luminosity goal such as beam collimation and focusing. The beam is focused through the Final Focus System while correcting higher order transport aberrations in order to deliver the design IP beam sizes. The chromatic contributions are amplified by the focusing strength of the two last quadrupoles named QD0 and QF1, reffered to as the Final Doublet (FD), and by the length of the final focal distance L* between QD0 and the IP. The chromaticity correction approach chosen for the CLIC FFS is based on the Local chromaticity correction scheme which uses interleaved pairs of sextupole magnets in the FD region in order to locally and simultaneously correct horizontal and vertical chromaticity. The current linear collider projects, the Compact Linear Collider (CLIC) and the International Linear Collider (ILC) have FFS lattices based on the Local Chromaticity correction scheme. This scheme is being tested in the Accelerator Test Facility 2 (ATF2) at KEK (Japan). This thesis concentrates on problems related to the optimization of BDS lattices for the simplification of the CLIC Machine Detector Interface (MDI) and on the experimental work for the implementation and study of a CLIClike FFS optics for the ATF2, referred to as ultra-low β* optics.

Depuis plusieurs années, les détecteurs courbes ont été proposés comme étant une nouvelle approche pour améliorer les performances des caméras. En courbant les détecteurs, une des aberrations optiques, la courbure de champ, peut en effet être annulée, ce qui permet d’avoir une meilleure résolution ou d’utiliser moins de lentilles pour une même qualité d’image.Ce travail de thèse propose d’étudier cette approche, en essayant de prendre en compte les aspects mécaniques, optiques et technologiques du système final. Tout d’abord, le lien entre la scène et la courbure des capteurs est théorisé. Ainsi, la position et la forme de l’objet par rapport au système optique influent sur la valeur de courbure du capteur optimale. Une forte compacité est permise pour les systèmes optiques possédant cette courbure. Ces études théoriques permettent de créer une nouvelle méthodologie de conception optique. Celle-ci débute par la détermination des limites mécaniques du capteur, pouvant casser lorsque la courbure est élevée. Intégrant ces limites et les changements théoriques observés, une architecture optique est choisie, donnant de hautes performances en compacité, résolution et champ de vue. De nouvelles tolérances sont établies pour la courbure. Ce système est ensuite fabriqué pour être caractérisé. La forme des montre un léger écart à la sphère. La courbure n’a pas d’impact significatif sur les performances électro-optiques des détecteurs. La qualité de l’image caractérisée est perturbée par des tilts ou décentrements probables. Enfin une caractérisation utilisant un capteur plan et l’optique imageant sur une surface courbe permet d’obtenir des informations sur la courbure idéale / In the past few years, curved sensors have been proposed to enhance optical systems. The curvature of these sensors improves off-axis aberrations, such as field curvature, which provides a better resolution and less complex optical systems.This work studies deformable and curved sensors development in a multidisciplinary approach. Firstly, scene and curved sensors are theoretically linked. The form and the position of the object change the curvature of the best image plane, leading to new relations adapted to optical systems with deformable sensors. Gains in compactness are also demonstrated. These investigations merge into a new methodology adapted to optical systems based on curved sensors that has been developed. The first step is to determine mechanical limits of the sensor such as maximum bending without breakage. Based on these limits, a new compact architecture is developed, providing high resolution and good field of view. New tolerances are determined to manufacture a system with its opto-mechanical mount. Finally, the entire imaging system is characterized. The form of the curved sensor is analyzed, showing few deviations from the ideal sphere. Electro-optical characterizations are realized and the image quality is determined according to the object distance, showing the effects of the deformable curvature. The ideal curved focal plane is also determined by combining a flat sensor to the manufactured optical system