Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-03-21T20:56:51Z No. of bitstreams: 2 Dissertação - Ana Paula Rodrigues de Magalhães - 2014.pdf: 1363967 bytes, checksum: f5dfff9110b37529ad94b507a41dae6b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-03-22T14:22:48Z (GMT) No. of bitstreams: 2 Dissertação - Ana Paula Rodrigues de Magalhães - 2014.pdf: 1363967 bytes, checksum: f5dfff9110b37529ad94b507a41dae6b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-03-22T14:22:48Z (GMT). No. of bitstreams: 2 Dissertação - Ana Paula Rodrigues de Magalhães - 2014.pdf: 1363967 bytes, checksum: f5dfff9110b37529ad94b507a41dae6b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-12-20 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / This study aims to evaluate the antibacterial effect of resin luting cements with and without NAg addition, and their influence on color, sorption and solubility. NAg were incorporated to two dual-cured resin luting cements (RelyX ARC - color A1 - and RelyX U200 - color A2 -) in two concentrations (0.05% and 0.07%) and the disc specimens obtained were tested for bacteria inhibition growth against Streptococcus mutans through optical density readings and scanning electron microscopy (SEM) analysis, for color changes with a spectrophotometer and for sorption and solubility after storage in water or 75% ethanol for 28 days, according to the ISO 4049:2010 specifications. Data were subjected to statistycal analysis with ANOVA and Tukey (p=0.05). The optical density of the culture broth indicated bacterial growth, but on SEM the only species identified was Bacillus subtilis. NAg produced significant color change on the resin cements, especially in the lighter color (RelyX ARC). Solubility values were very low for all groups, while sorption values were raised with NAg addition. The resin luting cements with NAg addition did not show antibacterial activity against S. mutans. They also showed perceptible color change and higher sorption than the materials without Nag. / O objetivo deste trabalho foi avaliar o efeito antibacteriano de cimentos resinosos com e sem adição de NAg, e a influência das mesmas na cor, sorção e solubilidade. Soluções de NAg foram incorporadas a dois cimentos resinosos de dupla polimerização (RelyX ARC - cor A1- e RelyX U200 – cor A2) em duas concentrações (0,05% e 0,07%) e os espécimes confeccionados em forma de discos foram testados quanto: à inibição de crescimento bacteriano (Streptococcus mutans) por meio de leituras de densidade ótica e análise em microscopia eletrônica de varredura (MEV); quanto à mudança de cor com um espectrofotômetro e quanto a sorção e solubilidade após armazenamento em água ou etanol 75% por 28 dias, de acordo com as normas da ISO 4049:2010. Os dados obtidos foram tabulados e submetidos a ANOVA e Tukey com p=0,05. A densidade ótica medida nos meios de cultura indicou crescimento bacteriano, mas a análise em MEV somente revelou a bactéria Bacillus subtilis. A NAg induziu mudança de cor significante nos cimentos resinosos, especialmente no de cor mais clara (RelyX ARC). Os valores de solubilidade foram muito baixos para todos os grupos, enquanto a sorção aumentou com a adição de NAg. Os cimentos resinosos adicionados de NAg não apresentaram efeito antibacteriano contra S mutans. Também apresentaram mudança de cor perceptível e maior sorção do que os materiais sem NAg.

Mesmo antes do estabelecimento de retinopatia detectável no exame clínico, a visão de cores e a sensibilidade ao contraste podem estar afetadas (Dean e cols., 1997; Kurtenbach e cols., 1999). Os déficits sensoriais têm sido atribuídos a alterações vasculares e da função de fotorreceptores (Greenstein e cols., 2000; Lieth e cols., 2000). Contudo, poucas conclusões acerca dos mecanismos fisiopatológicos têm sido obtidas. Este trabalho teve por objetivo identificar - em pacientes diabéticos tipo 2 com fundo de olho normal - possíveis alterações na visão de cores e sensibilidade ao contraste cromático e acromático e correlacionar os prejuízos sensoriais com a função eletrofisiológica da retina. A avaliação sensorial foi feita utilizando o Teste de Cores de Cambridge e o teste de sensibilidade ao contraste Psycho (Ventura e cols., 2003a, Ventura e cols., no prelo) e a função eletrofisiológica foi avaliada usando o eletrorretinograma de campo total (ERG). Os resultados dos pacientes diabéticos (n= 40; idade= 56 anos ± 9 e tempo de diabetes= 7 anos ± 9) foram comparados aos de grupos equiparado por idade. O limiar de discriminação de cores no eixo protan foi superior ao limite normal em 50% dos pacientes, no eixo deutan em 37% e tritan em 28%. A sensibilidade ao contraste cromático nos eixo vermelho/verde e azul/amarelo dos pacientes entre as freqüências espaciais de 0,2 a 2 cpg foi em média 10 dB menor que a dos pacientes, enquanto que na função de sensibilidade ao contraste acromático entre as freqüências espaciais de 0,3 a 20 cpg, a sensibilidade dos pacientes foi apenas 6 dB menor que a dos controles. No ERG, os componentes mais alterados foram os relacionados à atividade da retina interna. A amplitude da onda-b na resposta de bastonetes e dos potenciais oscilatórios foi inferior aos limites normais para 24% e 39% dos pacientes, respectivamente, e as latências correspondentes foram mais lentas em 45% e 76% dos pacientes. A perda da discriminação de cores dos pacientes teve padrão difuso; contrariando relatos anteriores de que a diabete provoca defeito da visão de cores no eixo tritan. Os resultados de sensibilidade ao contraste mostraram que o processamento cromático foi claramente mais afetado que os sistemas relacionados ao processamento acromático. Os dados do ERG indicaram haver alteração da atividade da retina interna. Estes achados confirmam e ampliam dados anteriores e sua aplicação clínica pode mudar o conceito de retinopatia diabética. / Before the establishment of retinopathy detectable in the ophthalmologic examination, color vision and contrast sensitivity may be altered in diabetic patients. (Dean e cols., 1997; Kurtenbach e cols., 1999). The sensory deficits have been attributed to vascular alterations and to (Greenstein e cols., 2000; Lieth e cols., 2000). However, there are no definite conclusions about the pathological mechanisms involved in the vision losses. The objective of this work was to identify in patients with type 2 diabetes and normal fundus, possible alterations in color vision and chromatic and achromatic contrast sensitivity, and to correlate the sensory losses with the electrophysiological function of the retina. The psychophysical evaluation was made using the computerized Cambridge Colour Test and PSYCHO contrast sensitivity test. (Ventura e cols., 2003a, Ventura e cols., in press). Electrophysiological function was assessed using the full field electroretinogram (ERG). Patient\'s results (n= 40; age= 56 years ± 9 time of diabetes= 7 years ± 9) with results obtained with age-matched controls. The color discrimination threshold was higher than the normal limit in 50% of the patients in the protan axis, in 37% in the deutan axis and in 28% in the tritan axis. Chromatic contrast sensitivity in both the red/green and the blue yellow axes showed a loss of about 10 dB in patients as compared to controls throughout the frequencies tested (0.2 to 2cpd). In the achromatic contrast sensitivity function the loss found in patients was smaller, of about 6 dB throughout the frequency range tested (3 to 20 cpd). In the ERG b-wave and in the oscillatory potentials the amplitudes were smaller, respectively, in 24% and 39% of the patients compared to controls. The corresponding latencies were longer in 45% and 76% of the patients. The pattern of color discrimination losses of the patients indicates that there is a diffuse loss of color vision, as opposed to most previous results indicating that tritan losses. The contrast sensitivity results showed that the chromatic pathways were more affected than the achromatic pathways. The alterations found in the full field ERG are suggestive of inner retina losses. The present findings confirm and extend previous reports. Their clinical application may change the concept of diabetic retinopathy.

No / Area V3A was identified in five human subjects on both a functional and retinotopic basis using functional magnetic resonance imaging techniques. V3A, along with other visual areas responsive to motion, was then targeted for disruption by repetitive transcranial magnetic stimulation (rTMS) whilst the participants performed a delayed speed matching task. The stimuli used for this task included chromatic, isoluminant motion stimuli that activated either the L-M or S-(L+M) cone-opponent mechanisms, in addition to moving stimuli that contained only luminance contrast (L+M). The speed matching task was performed for chromatic and luminance stimuli that moved at slow (2 degrees/s) or faster (8 degrees/s) speeds. The application of rTMS to area V3A produced a perceived slowing of all chromatic and luminance stimuli at both slow and fast speeds. Similar deficits were found when rTMS was applied to V5/MT+. No deficits in performance were found when areas V3B and V3d were targeted by rTMS. These results provide evidence of a causal link between neural activity in human area V3A and the perception of chromatic isoluminant motion. They establish area V3A, alongside V5/MT+, as a key area in a cortical network that underpins the analysis of not only luminance but also chromatically-defined motion.

In this paper, we investigate how controlled changes to image properties and orientation affect eye movements for repeated viewings of images of natural scenes. We make changes to images by manipulating low-level image content (such as luminance or chromaticity) and/or inverting the image. We measure the effects of these manipulations on human scanpaths (the spatial and chronological path of fixations), additionally comparing these effects to those predicted by a widely used saliency model (L. Itti & C. Koch, 2000). Firstly we find that repeated viewing of a natural image does not significantly modify the previously known repeatability (S. A. Brandt & L. W. Stark, 1997; D. Noton & L. Stark, 1971) of scanpaths. Secondly we find that manipulating image features does not necessarily change the repeatability of scanpaths, but the removal of luminance information has a measurable effect. We also find that image inversion appears to affect scene perception and recognition and may alter fixation selection (although we only find an effect on scanpaths with the additional removal of luminance information). Additionally we confirm that visual saliency as defined by L. Itti and C. Koch's (2000) model is a poor predictor of real observer scanpaths and does not predict the small effects of our image manipulations on scanpaths.

Approved for public release; distribution in unlimited. / Traditionally, digital imaging systems rely on the use of dedicated photodetectors to capture specific wavelengths in the visible spectrum. These photodetectors, which are commonly made of silicon, are arranged as arrays to capture the red, green and blue wavelengths. The signal captured by the individual photodetectors must then be interpolated and integrated to obtain the closest color match and the finest possible resolution with reference to the actual object. The use of spatially separated detectors to sense primary colors reduces the resolution by a factor of three compared to black and white imaging. The FOVEON detector technology greatly improves the color and resolution of the image through its vertically arranged, triple well photodetector. This is achieved by exploiting the variation of absorption coefficient of silicon with wavelength in the visible spectrum. Hence, in a silicon detector, the shorter wavelength (e.g. blue) would be mainly absorbed at a shallow depth. A longer wavelength (e.g. red) would penetrate the material deeper than the shorter wavelengths and be primarily absorbed at a greater depth. By producing a layered silicon detector, all three primary colour wavelengths of red, green and blue can be captured simultaneously. This thesis aims to study the FOVEON camera's ability to image light from the near Infrared (NIR) to the Ultra-Violet (UV) range of the electromagnetic spectrum. The imaged obtained using a set of bandpass filters show that the camera has response both in the UV as well as NIR regions. / Major, Singapore Armed Forces

Este trabalho foi desenvolvido com o intuito de se estabelecer uma metodologia para a classificação das cores de imagens digitais em cores perceptuais para se gerar um vetor de características que permita recuperar imagens através de seu conteúdo em uma base de dados. Em trabalhos e estudos correlatos analisados, as metodologias de agrupamento das diversas cores possíveis de uma imagem não permitem uma associação entre a cor digitalizada e a cor percebida por seres humanos. Estudos mostram que a maioria das culturas humanas associam às cores apenas onze termos: vermelho, amarelo, violeta, azul, verde, rosa, marrom, preto, branco, laranja e cinza. Este trabalho propõe, portanto, uma metodologia baseada em regras da lógica fuzzy, que permite associar a todas as possíveis cores de imagens digitais uma das onze cores culturais definidas, criando assim um histograma perceptual de cores. Isso permitiu a geração de um vetor de características para a recuperação de imagens baseada em conteúdo em uma base de dados. / This work aims at establishing a digital image classification methodology based on perceptual colors, by generating a feature vector that allows retrieving images from a database by their content. In related works the methodologies of grouping the diverse possible colors of an image do not allow associate digitized colors and those colors perceived by human beings. Studies show that the majority of human being culture associates only eleven terms to all the possible colors: red, yellow, blue, green, pink, brown, black, white, purple, orange and gray. This work purpose a methodology based on fuzzy logic that allows to associate the eleven cultural color terms with all of digitized colors by a perceptual color histogram. The image color quantization generates a feature vector used for content-based image retrieval. The results show that it is possible to use the perceptual color histogram for CBIR and in the semantic gap reduction.

No description available.

Este trabalho foi desenvolvido com o intuito de se estabelecer uma metodologia para a classificação das cores de imagens digitais em cores perceptuais para se gerar um vetor de características que permita recuperar imagens através de seu conteúdo em uma base de dados. Em trabalhos e estudos correlatos analisados, as metodologias de agrupamento das diversas cores possíveis de uma imagem não permitem uma associação entre a cor digitalizada e a cor percebida por seres humanos. Estudos mostram que a maioria das culturas humanas associam às cores apenas onze termos: vermelho, amarelo, violeta, azul, verde, rosa, marrom, preto, branco, laranja e cinza. Este trabalho propõe, portanto, uma metodologia baseada em regras da lógica fuzzy, que permite associar a todas as possíveis cores de imagens digitais uma das onze cores culturais definidas, criando assim um histograma perceptual de cores. Isso permitiu a geração de um vetor de características para a recuperação de imagens baseada em conteúdo em uma base de dados. / This work aims at establishing a digital image classification methodology based on perceptual colors, by generating a feature vector that allows retrieving images from a database by their content. In related works the methodologies of grouping the diverse possible colors of an image do not allow associate digitized colors and those colors perceived by human beings. Studies show that the majority of human being culture associates only eleven terms to all the possible colors: red, yellow, blue, green, pink, brown, black, white, purple, orange and gray. This work purpose a methodology based on fuzzy logic that allows to associate the eleven cultural color terms with all of digitized colors by a perceptual color histogram. The image color quantization generates a feature vector used for content-based image retrieval. The results show that it is possible to use the perceptual color histogram for CBIR and in the semantic gap reduction.

No description available.

Through two books and a series of video documentations of live performances Mette Ingvartsen makes choreography into a territory of physical, artistic and social experimentation. The Artificial Nature Series focusses on how relations between human and non-human agency can be explored and reconfigured through choreography. By investigating and creating a ‘nonhuman theater’ questions regarding material agency, ecology, natural disasters, the Anthropocene and non-subjective performativity are posed. The resulting reflections are closely related to the poetic principles utilized to create the performances, while also drawing connections to territories outside theater. By contrast, 69 positions inscribes itself into a history of human performance with afocus on nudity, sexuality and how the body historically has been a site for political struggles. By creating a guided tour through sexual performances – from the naked protest actions of the 1960’s, through an archive ofpersonal performances into a reflection on contemporary sexual practice – this solo work rethinks audience participation and proposes a notion of soft and social choreography. The contrasting performative strategiesarticulate a twofold notion of expanded choreography: on the one hand movement is extended beyond the human body by including the agency of nonhuman performers, and on the other hand, movement is expanded into animaginary and virtual space thanks to ‘language choreography’. / <p>LINKS</p><p>https://vimeo.com/164552586</p><p>https://vimeo.com/164558381</p>