Le sujet de ma thèse est l’étude de la diffraction par des trous sub-longueur percés dans des films métalliques, ainsi que la compréhension du rôle des plasmons de surface (SPs) dans la diffraction en champ lointain. Nous avons construit un goniomètre « fait maison » de haute qualité. Une série de trous unique percés dans un film opaque et variant continûment de k • r >> 1 à k • r << 1 ont été explorées. Ici, k est le vecteur d'onde de l'onde incidente et r est le rayon du trou. Les résultats expérimentaux indiquent que la diffraction de la lumière par un trou unique peut être séparée en quatre régimes, dépendant de la polarisation incidente. Une expression analytique simple révèle pour la première fois, l’implication de deux facteurs compétitifs: l'un lié aux plasmons de surface, et l'autre provenant du couplage du champ aux modes de guide d'onde de l'ouverture. Lorsque le trou est entouré par des corrugations concentriques (structure d'oeil de boeuf), et est illuminé avec les rainures sur le côté de sortie, l'effet de collimation est observé: la diffraction en champ lointain est confinée dans un très petit angle solide. L’influence des paramètres géométrique sur la figure de diffraction de l’œil de bœuf a été étudié et des motifs de diffraction dont la largeur est inférieure à 1 ° dans le champ lointain ont été atteints. Un autre mode de surface (CWs), différent des SPs, a été étudié sur des films de tungstène. Il a été démontré que les CWs permettent également d’obtenir un effet de collimation. À titre de comparaison, nous avons montré que la transmission exaltée est bien plus faible pour les CWs que pour les SPs sur nanostructures. / The theme of my thesis is to investigate the diffraction behavior of subwavelength holes in metal films, and to understand the surface plasmons’ (SPs) role in aperture far-field diffraction. We have built a home-made goniometer setup with high-level quality. A series of single hole continuously ranging from k•r>>1 to k•r<<1 in a flat opaque film were explored, where k is the wavevector of the incident wave and r is the radius of the hole. The experimental results indicated that the diffraction of single hole can be classified into four regimes, depending on the input polarization. A simple analytical expression reveals for the first time the subtle interplay of two competing factors: one related to surface plasmon excitation and the other originating in the coupling of the field to the waveguide mode of the aperture. When the hole is surrounded by concentric grooves (bull’s eye structure) and is illuminated with the grooves on the output side, the beaming effect occurs: far-field diffraction is confined in very small solid angle. The effects of geometrical parameters on bull’s eye diffraction have been studied and the diffraction patterns with the width less than 1° in the far field have been achieved. Another surface waves (CWs) different from SPs on tungsten films were studied. It was demonstrated that the CWs have beaming effect as well. By comparison we showed that CWs display much weaker enhancement in transmission than SPs through nanostructures.

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Ultraviolet colouration of flowers varies both among and within species. The significance of these patterns and differences among them was usually associated with a visual per- ception of pollinators. In this study we examine the variation of marsh marigold's (Caltha palustris) bull's-eye pattern on a basis of 289 observed individuals from 32 distinct locati- ons. The variation of this pattern is shown to be quite large within separate locations and the pattern is predictably changing according to latitude. This trend of darker colouration towards the equator is an another example of a more widely understood Gloger's rule in the plant kingdom. The effect of ultraviolet radiation appears to be one of the most likely causes of this phenomenon. Hereafter we analyse the weakness of this explanation, the gaps in current knowledge and propose possible directions of further research. Keywords: ultraviolet, bull's-eye, marsh marigold, Caltha palustris, Gloger's rule

Tomografia computadorizada por emissão de fóton único (SPECT) é uma modalidade da medicina nuclear baseada na medida da distribuição espacial de um radionuclídeo. Esta técnica é amplamente utilizada em cardiologia para avaliar problemas de perfusão miocárdica, relacionados ao fluxo sanguíneo nas artérias coronárias. As imagens SPECT proporcionam melhor separação das regiões do miocárdio e facilitam a localização e a definição dos defeitos de perfusão. Um dos grandes desafios em estudos SPECT é a eficiente apresentação da informação, uma vez que um único estudo pode gerar imagens de centenas de cortes a serem analisados. Para resolver este problema, são utilizados mapas polares (também conhecidos como gráficos Bulls Eye). Mapas polares são construídos a partir de cortes tomográficos do ventrículo esquerdo e apresentam as informações dos exames de forma sumarizada, em uma imagem bidimensional. Essa dissertação apresenta um método para segmentação do ventrículo esquerdo em estudos SPECT do miocárdio e a construção de mapas polares. A segmentação do ventrículo esquerdo é realizada para facilitar o processo de geração automática de mapas polares. O método desenvolvido utiliza a transformada watershed, no contexto do paradigma de Beucher-Meyer. Para visualização dos resultados, foi desenvolvida uma aplicação, chamada Medical Image Visualizer (MIV). O MIV será disponibilizado como projeto Open Source, podendo ser livremente utilizado e/ou modificado pela comunidade de usuários, desenvolvedores e pesquisadores. / Single photon emission computed tomography (SPECT) is a nuclear medicine tomographic imaging technique based on the measurement of spatial distribution of a radionuclide. This technique is widely used in cardiology to assess myocardial perfusion problems related to blood flow in coronary arteries. SPECT images provide better separation of regions of the myocardium and facilitate the location and definition of perfusion defects. One of the major challenges in SPECT studies is the efficient presentation of information, since a single study can generate hundreds of images of slices to be analyzed. To address this issue, polar maps (also known as Bulls Eye display) are used. Polar maps are built from slices of the left ventricle and provide summarized information of exams in a two dimensional image. This dissertation presents a method for the segmentation of the left ventricle in myocardial SPECT studies and the construction of polar maps. The segmentation of the left ventricle is performed to facilitate the process of automatic generation of polar maps. The method uses the watershed transform, in the context of the Beucher-Meyer paradigm. To display the results, it was developed an application called Medical Image Visualizer (MIV). MIV will be available as an Open Source project and the communities of users, developers and researchers will be able to freely use and/or modify the application.

Tomografia computadorizada por emissão de fóton único (SPECT) é uma modalidade da medicina nuclear baseada na medida da distribuição espacial de um radionuclídeo. Esta técnica é amplamente utilizada em cardiologia para avaliar problemas de perfusão miocárdica, relacionados ao fluxo sanguíneo nas artérias coronárias. As imagens SPECT proporcionam melhor separação das regiões do miocárdio e facilitam a localização e a definição dos defeitos de perfusão. Um dos grandes desafios em estudos SPECT é a eficiente apresentação da informação, uma vez que um único estudo pode gerar imagens de centenas de cortes a serem analisados. Para resolver este problema, são utilizados mapas polares (também conhecidos como gráficos Bulls Eye). Mapas polares são construídos a partir de cortes tomográficos do ventrículo esquerdo e apresentam as informações dos exames de forma sumarizada, em uma imagem bidimensional. Essa dissertação apresenta um método para segmentação do ventrículo esquerdo em estudos SPECT do miocárdio e a construção de mapas polares. A segmentação do ventrículo esquerdo é realizada para facilitar o processo de geração automática de mapas polares. O método desenvolvido utiliza a transformada watershed, no contexto do paradigma de Beucher-Meyer. Para visualização dos resultados, foi desenvolvida uma aplicação, chamada Medical Image Visualizer (MIV). O MIV será disponibilizado como projeto Open Source, podendo ser livremente utilizado e/ou modificado pela comunidade de usuários, desenvolvedores e pesquisadores. / Single photon emission computed tomography (SPECT) is a nuclear medicine tomographic imaging technique based on the measurement of spatial distribution of a radionuclide. This technique is widely used in cardiology to assess myocardial perfusion problems related to blood flow in coronary arteries. SPECT images provide better separation of regions of the myocardium and facilitate the location and definition of perfusion defects. One of the major challenges in SPECT studies is the efficient presentation of information, since a single study can generate hundreds of images of slices to be analyzed. To address this issue, polar maps (also known as Bulls Eye display) are used. Polar maps are built from slices of the left ventricle and provide summarized information of exams in a two dimensional image. This dissertation presents a method for the segmentation of the left ventricle in myocardial SPECT studies and the construction of polar maps. The segmentation of the left ventricle is performed to facilitate the process of automatic generation of polar maps. The method uses the watershed transform, in the context of the Beucher-Meyer paradigm. To display the results, it was developed an application called Medical Image Visualizer (MIV). MIV will be available as an Open Source project and the communities of users, developers and researchers will be able to freely use and/or modify the application.

Traditional readings of George Bernard Shaw's texts suggest that he is not a pure Marxist socialist because of the spiritual and nationalist aspects of his vision. This thesis attempts to confront Shaw's politics in order to demonstrate that he indeed offers a viable socialist program. Overlaying his socialism with Louis Althusser's concepts of "overdetermination," "structural causality," and "ideology" reveals that Shaw uses relatively autonomous instances of the superstructure toward socialist ends. This reevaluation of Shaw is best achieved through a combined reading of three of his major plays -- John Bull's Other Island, Man and Superman, and Major Barbara. In John Bull, Shaw incorporates the controversy of nationalism into his socialist vision by explaining it as an inevitable step in the development of an oppressed nation toward socialism. Man and Superman discusses the need for spirituality in the form of Shaw's concepts of Creative Evolution and the Life Force, which drive toward the development of a consciousness that recognizes socialism as the only sustainable internationalist program. Major Barbara combines Shaw's socialist and spiritual views by showing that both stand in reciprocal relation to each other; they are equally necessary to the Shavian world, one providing the ideal social system, the other the most enlightened human sensibility. This project demonstrates that Shaw's integration of these elements usually considered contradictory to Marxism becomes a way to understand him as practicing the Althusserian idea that any displacements of the infrastructure are economic in the last instance. / Graduation date: 1999

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-05T13:57:00Z No. of bitstreams: 1 PGPV10MA231.pdf: 289994 bytes, checksum: f6f6518eed8d4a3460fcad5b1cca7663 (MD5) / Made available in DSpace on 2018-03-05T13:57:00Z (GMT). No. of bitstreams: 1 PGPV10MA231.pdf: 289994 bytes, checksum: f6f6518eed8d4a3460fcad5b1cca7663 (MD5) Previous issue date: 2010-05-28 / Capes / Brazil is one of the main world producers of fruit, but much of the production is lost due to the high incidence of postharvest rots. The control with fungicides has been suffering restrictions by consumers and fruit importing countries. The benefits and viability of hot water spraying and UV-C radiation was shown in other countries and in Brazil to control rots caused by Botryosphaeria dothidea and Penicillium expansum on apples. This project aimed to assess the effect of heat treatment and/or UV-C radiation to control at postharvest bull’seye rot caused by Cryptosporiopsis perennans on apples, and to evaluate equipments for the implementation of these treatments. In the laboratory, the sensitivity of conidia of the pathogen to heat treatment was evaluated at temperatures of 28, 45, 50 and 55ºC, for 15 and 30 seconds, and to UV-C radiation at doses of 0.018 x 104, 0.037 x 104, 0.075 x 104, 0.150 x 104, 0.375 x 104, 0.750 x 104, 1.500 x 104 and 3.000 x 104 ergs mm-2. There was a reduction of more than 99% in the viability of conidia of C. perennans treated at or above 50°C for 15 seconds, and with UV-C radiation at doses 0.75 x 104 ergs mm-2. The combinations between heat treatment exposure time and UV-C radiation were also evaluated on apples inoculated with C. perennans in an experimental packing line. In this case, the spraying of hot water at 50°C for 15 seconds, and the treatment with UV-C radiation at the dose of 0.375 x 104 ergs mm-2, were effective in controlling the epiphytic population of C. perennans on 'Gala', 'Fuji' and 'Pink Lady' apples. Apples inoculated and naturally infected with the pathogen, after different periods of cold storage under controlled atmosphere (CA), were assessed for the effects of physical treatments to control bull's-eye rot in a commercial packing line. On 'Fuji' apples, stored for one, four and eight months under CA, and 'Gala', stored for five months under CA, the spraying of hot water at 50ºC for 12 seconds and/or treatment with UV-C radiation at 0.0069 x 104 ergs mm-2 reduced in more than 45% the incidence of bull's-eye rot. Therefore, the physical treatments tested reduced the postharvest losses on apples caused by bull’s-eye rot, providing competitiveness gain to the industry / O Brasil é um dos principais produtores mundiais de frutos, mas grande parte da produção é perdida devido à elevada incidência de podridões pós-colheita. O controle com fungicidas vem sofrendo restrições pelos consumidores e pelos países importadores de frutos. O benefício e a viabilidade do uso da aspersão do fruto com água aquecida e da radiação UV-C foi demonstrada no exterior e também no Brasil no controle de podridões em maçãs causadas por Penicillium expansum e Botryosphaeria dothidea. Este projeto visou determinar o efeito do tratamento térmico e/ou com radiação UV-C para o controle pós-colheita da podridão olho-de-boi em maçãs, causada por Cryptosporiopsis perennans, e avaliar equipamentos para a execução destes tratamentos. Em laboratório, foi avaliada a sensibilidade dos conídios do patógeno ao tratamento térmico nas temperaturas de 28, 45, 50 e 55ºC, por 15 e 30 segundos, e à radiação UV-C, nas doses de 0,018 x 104, 0,037 x 104, 0,075 x 104, 0,150 x 104, 0,375 x 104, 0,750 x 104, 1,500 x 104 e 3,000 x 104 ergs mm-2. Ocorreu redução superior a 99% na viabilidade dos conídios de C. perennans tratados com temperatura igual ou superior a 50ºC por 15 segundos, e com radiação UV-C na dose igual ou superior a 0,75 x 104 ergs mm-2. Posteriormente, foram avaliadas combinações de tempos de exposição ao tratamento térmico e à radiação UV-C em maçãs previamente inoculadas com C. perennans numa linha de seleção experimental. Neste caso, a aspersão de água aquecida, na temperatura de 50ºC por 15 segundos, e o tratamento com radiação UV-C, na dose de 0,375 x 104 ergs mm-2, mostraramse eficientes no controle da população epífita de C. perennans em maçãs 'Gala', 'Fuji' e 'Pink Lady'. Por fim, avaliou-se o efeito dos tratamentos, aplicados numa linha de seleção comercial, na incidência da podridão olho-de-boi em maçãs inoculadas e com infecção natural, com diferentes períodos de armazenamento em condição de atmosfera controlada (AC). Em maçãs 'Fuji' armazenadas por um, quatro e oito meses em AC, e 'Gala' armazenada por cinco meses em AC, o uso da aspersão de água aquecida a 50ºC durante 12 segundos e/ou da radiação UV-C na dose de 0,0069 x 104 ergs mm-2 reduziu em mais de 45% a incidência da podridão olho-de-boi. Assim, os tratamentos físicos testados reduzem as perdas pós-colheita ocasionadas pela podridão olho-de-boi em maçãs, proporcionando ao setor ganho em competitividade

The theme of my thesis is to investigate the diffraction behavior of subwavelength holes in metal films, and to understand the surface plasmons' (SPs) role in aperture far-field diffraction. We have built a home-made goniometer setup with high-level quality. A series of single hole continuously ranging from k*r>>1 to k*r<