Orientador: Silvana Artioli Schellini / Banca: Eliana Chaves Jorge / Banca: Antonio Carlos Rodrigues / Resumo: O objetivo do estudo foi avaliar a influência do diabetes sobre os vasos da íris, corpo ciliar e retina. Para isto, foi realizado estudo experimental, utilizando 20 ratos da raça Wistar, divididos em dois grupos: Grupo Controle (GC) e Grupo Diabético (GD). A indução do diabetes foi feita por injeção de aloxana, 42 mg/Kg de peso. Os animais foram observados em 3 momentos experimentais: M1-15 dias após a indução do diabetes, M2 -1 mês após M1 e M3 -12 meses após M1. Foram considerados para o estudo os animais do GD que em M1 apresentavam diabetes grave. Realizou-se acompanhamento diário de parâmetros clínicos (peso, diurese, ingestão hídrica e ingestão alimentar) e avaliação mensal de glicemia e glicose urinária. Nos momentos experimentais M2 e M3 foram realizadas enucleação e preparo dos olhos para avaliação sob microscopia eletrônica de transmissão. Os resultados obtidos mostraram que os animais diabéticos tiveram importante redução de peso, aumento de ingestão hídrica, aumento de ingestão alimentar e aumento de diurese, em relação aos animais controle. Na avaliação morfológica os três grupos de vasos tiveram alterações similares, com espessamento da membrana basal nas células endoteliais e pericitos, maior número de corpos densos, lisossomos, vesículas, vacúolos e "figuras de mielina", que estavam presentes em GCM2 e foram mais acentuadas nos grupos diabéticos. Não foram observados microaneurismas na parede vascular. A análise morfométrica mostrou aumento significativo na espessura da membrana basal de vasos irianos nos animais diabéticos. Concluí-se que os vasos da íris, corpo ciliar e retina sofrem a influência do estado diabético. As alterações são progressivas, afetando tanto as células endoteliais, como as pericíticas. / Abstract: The purpose of this study was to evaluate the influence of diabetes on vessels of iris, ciliary's body and retina. For this, prospective experiment was accomplished, using 20 Wistar rats, divided in two groups: Control Group (CG) and Diabetic Group (DG). The diabetes induction was made by aloxana injection, 42 mg/Kg of weight. The animals had been observed at 3 experimental moments: M1-15 days after the diabetes induction, M2 - 1 month M1 and M3 -12 months after M1. They were considered for the study the animals of the DG that presented serious diabetes in M1. Clinical parameters had daily been followed (weight, diuresis, water ingestion and alimentary ingestion) and monthly evaluation of glycemia and urinary glucose. At the experimental moments M2 and M3 it was realized enucleation and preparation of the eyes for optic microscopy and electronic transmission microscopy evaluation. The gotten results had shown that the diabetic animals had had important weight reduction, water ingestion increase, alimentary ingestion increase and diuresis increase, compared to the animals of the CG. In the morphologic evaluation it has been observed that the three groups of vessels have had similar alterations, with thickening of the basal membrane in the endothelial cells and pericytes, greater number of dense bodies, lysosomes, vesicles, vacuoles and "myelin figures" that they were in GCM2 and had been accentuated in diabetic groups. Microaneurysms in the vascular wall had not been observed. The morphometric analysis showed significant increase in the thickness of the basal membrane of iris vessels in diabetic animals. We conclude that iris, ciliary's body and retina vessels suffer the influence from the diabetic state. The alterations are gradual, affecting in such a way the endothelial cells, as the pericytes. / Doutor

Orientador: Roberto de Andrade Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica "Gleb Wataghin." / Made available in DSpace on 2018-07-21T13:19:17Z (GMT). No. of bitstreams: 1 Silva_CibelleCelestino_M.pdf: 5402297 bytes, checksum: 0108f6d015b5fbee35a786d9aec59a46 (MD5) Previous issue date: 1996 / Resumo: Esta dissertação analisa a estrutura e fundamentação da teoria das cores de Newton através de um estudo detalhado das proposições e dos experimentos do Livro I do Opticks, publicado em 1704. A análise aqui apresentada leva em conta outros estudos de Newton sobre óptica, tais como seu caderno de anotações de 1664-65, o artigo em que Newton publicou pela primeira vez a sua teoria em 1672 nas Philosophical Transactions of lhe Royal Society, as críticas que Hooke, Pardies, Huygens e outros pesquisadores fizeram a esse artigo, e as respostas de Newton a essas críticas. A dissertação analisa os argumentos usados por Newton e mostra que nem sempre ele seguiu o método indutivista que se propunha seguir. Contrariamente à visão tradicional que via nesse trabalho de Newton um uso exemplar do método experimental, a dissertação aponta vários problemas dos experimentos e da argumentação de Newton. Em particular, mostra que ele não apresentou (nem poderia ter apresentado) uma prova experimental da composição da luz branca solar / Abstract: This dissertation analyses the structure and foundation of Newton's theory of colours through a detailed study of the propositions and experiments of Book I of Opticks, published in 1704. The analysis presented here takes into account some other of Newton's studies on optics, including his Notebook (1664-65), the paper published in 1672 in the Philosophical Transactions of the Royal Society, where Newton made public for the first time his theory , the critical remarks by Hooke, Pardies, Huygens and other researchers to that paper, and Newton's answers to his critics. The dissertation analyses the arguments used by Newton and shows that sometimes he failed to follow the inductivist method the tried to follow. The dissertation points out several difficulties behind Newton's experiments and arguments. In particular, it is shown that he did not present (nor could have presented) an experimental proof of the composition of the white light from the Sun / Mestrado / Física / Mestre em Física

Um dos fatores imprescindíveis no resultado estético satisfatório do tratamento reabilitador protético ocular é a reprodução fiel da íris do olho remanescente na íris protética. É a dissimulação da perda para os pacientes afetados. Este trabalho apresenta duas novas técnicas de confecção da íris protética, utilizando imagem digitalizada da íris remanescente, obtida por meio de imagem fotográfica impressa em etiqueta autocolante e em adesivo. Em função da fotodegradação que compromete a longevidade das próteses oculares, decidiu-se avaliar a estabilidade das cores, comparando-se ambas as técnicas, através de teste de envelhecimento acelerado. Para os ensaios foram confeccionados corpos de prova simulando a íris protética, divididos em dois grupos: adesivo e etiqueta autocolante, nas cores verde, azul, marrom e preto. A variação do grau de degradação foi avaliada por leitura colorimétrica inicial e, em três intervalos semanais durante o envelhecimento artificial com radiação ultravioleta. A análise estatística sugere que quando as cores foram avaliadas em função do período de ensaio de envelhecimento artificial, somente na cor azul no grupo adesivo houve diferença estatisticamente significante. Quando avaliadas em função do grupo e período de ensaio, os testes estatísticos indicam que não houve diferença entre as cores entre adesivo. Nenhuma das cores entre os grupos apresentou uma degradação de cor acima do nível clinicamente aceitável. / One of the essential factors in satisfactory final result of ocular prosthetic rehabilitation treatment is a faithful reproduction of the iris of the eye remaining in prosthetic iris. It concealment loss for affected patients. This paper presents two new techniques to manufacture prosthetic iris, using the remaining iris scanned image, obtained by photographic image printed sticker and adhesive. Depending on the photo degradation that compromises the longevity of artificial eyes, decided to evaluate the stability of colors, comparing both techniques, through accelerated aging test. For the tests were prepared specimens simulating prosthetic iris, divided into two groups: adhesive sticker and, in green, blue, brown and black. The variation of the degree of degradation was evaluated by colorimetric reading before and after and three weekly intervals during aging with artificial ultraviolet radiation. Statistical analysis suggests that when the colors were evaluated according to the period of artificial aging test, only in blue color in the adhesive group difference was statistically significant. When evaluated as a function of group and trial period, the statistical tests indicate no difference between the colors of adhesive. None of the colors between the groups showed color degradation above the clinically acceptable level.

A reprodução fiel da íris do olho remanescente na confecção da prótese ocular é fator fundamental no resultado estético e na dissimulação da perda para os pacientes afetados. Este trabalho apresenta uma nova técnica de confecção da íris protética, substituindo a pintura tradicional da mesma, pela imagem digitalizada da íris remanescente, obtida através de fotografia impressa em papel fotográfico. Decidiu-se avaliar a estabilidade das cores, comparando-se a técnica de pintura com a obtida através da fotografia digital, sob a ação de dois fatores: ação térmica do ciclo de polimerização da resina acrílica na confecção da prótese e a incidência da luz solar, principal agente de fotodegradação que compromete a longevidade das próteses oculares, através de teste de envelhecimento acelerado. Foram assim, confeccionados corpos de prova simulando a íris protética, divididos em dois grupos: pintura e fotografia, nas cores azul, amarelo, preto, marrom e verde. Foi realizada leitura colorimétrica inicial e após submetê-los às condições térmicas de polimerização. Posteriormente os corpos de prova foram testados durante três semanas através de ensaio de envelhecimento acelerado artificialmente com radiação ultravioleta A, com leituras colorimétricas semanais. A análise estatística sugere que, após a polimerização, as cores amarelo e marrom apresentaram diferenças significativas entre os grupos, sendo que, a cor amarelo na amostra pintura apresentou uma degradação um pouco acima do nível clinicamente aceitável. Após o ensaio de envelhecimento, não houve diferença significativa entre as amostras pintura e fotografia para as cores verde e amarelo, com alteração um pouco acima do nível clinicamente aceitável. Para as cores marrom e preto ocorreram diferenças significantes, com variações em níveis clinicamente aceitáveis; para a cor azul em níveis elevados, inviáveis clinicamente tanto na fotografia como na pintura. / The accurate iris reproduction in the making of ocular prosthesis for the remaining eye is a fundamental factor for the loss dissimulation aesthetic result in affected patients. This paper presents a new technique for the making of prosthetic iris that consists in substituting the traditional painting of the prosthesis for a digitalized image of the remaining iris, obtained through a picture printed in a photographic paper. It was decided to evaluate the stability of the colors by comparing the painting technique with the digital picture, for this two factors were considered: thermal conditions of the acrylic resin polymerization cycle in the prosthesis making and incidence of the sun light, which is the main photo degradation agent that affect the longevity of the ocular prosthesis, through the accelerated aging test. Then proof bodies simulating the prosthetic iris were made and divided into two groups: painted (in the colors blue, yellow, black, brown and green) and picture. An initial colorimetric scanning was made before and after submitting the bodies to the thermal conditions of the polymerization process. The proof bodies were then tested artificially for three weeks using the accelerated aging with A-ultraviolet radiation technique and proceeding to colorimetric scans weekly. Statistical analysis suggests that after the temperature action in the polymerization cycle, the yellow and brown color presented significative alteration between both groups and the yellow color in the painted presented degradation slightly above the acceptable clinical level. After the aging test, there was no significant difference between the samples in both groups for the green and yellow colors, however, for the brown and black colors significant differences were observed, with variations in clinically acceptable levels, and for blue color in high levels, clinically impracticable, in both groups.

This master thesis evaluates the use of off-the-shelf standard cameras for biometric identification of the human iris. As demands on secure identification are constantly rising and as the human iris provides with a pattern that is excellent for identification, the use of inexpensive equipment could help iris recognition become a new standard in security systems. To test the performance of such a system a review of the current state of the research in the area was done and the most promising methods were chosen for evaluation. A test environment based on open source code was constructed to measure the performance of iris recognition methods, image quality and recognition rate. In this paper the image quality of a database consisting of images from a standard camera is assessed, the most important problem areas identified, and the overall recognition performance measured. Iris recognition methods found in literature are tested on this class of images. These together with newly developed methods show that a system using standard equipment can be constructed. Tests show that the performance of such a system is promising.

Memoria para optar al título de Ingeniero Agrónomo, mención Producción Agrícola

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This dissertation develops an innovative approach towards less-constrained iris biometrics. Two major contributions are made in this research endeavor: (1) Designed an award-winning segmentation algorithm in the less-constrained environment where image acquisition is made of subjects on the move and taken under visible lighting conditions, and (2) Developed a pioneering iris biometrics method coupling segmentation and recognition of the iris based on video of moving persons under different acquisitions scenarios. The first part of the dissertation introduces a robust and fast segmentation approach using still images contained in the UBIRIS (version 2) noisy iris database. The results show accuracy estimated at 98% when using 500 randomly selected images from the UBIRIS.v2 partial database, and estimated at 97% in a Noisy Iris Challenge Evaluation (NICE.I) in an international competition that involved 97 participants worldwide involving 35 countries, ranking this research group in sixth position. This accuracy is achieved with a processing speed nearing real time. The second part of this dissertation presents an innovative segmentation and recognition approach using video-based iris images. Following the segmentation stage which delineats the iris region through a novel segmentation strategy, some pioneering experiments on the recognition stage of the less-constrained video iris biometrics have been accomplished. In the video-based and less-constrained iris recognition, the test or subject iris videos/images and the enrolled iris images are acquired with different acquisition systems. In the matching step, the verification/identification result was accomplished by comparing the similarity distance of encoded signature from test images with each of the signature dataset from the enrolled iris images. With the improvements gained, the results proved to be highly accurate under the unconstrained environment which is more challenging. This has led to a false acceptance rate (FAR) of 0% and a false rejection rate (FRR) of 17.64% for 85 tested users with 305 test images from the video, which shows great promise and high practical implications for iris biometrics research and system design.

Personal identity refers to a set of attributes (e.g., name, social insurance number, etc.) that are associated with a person. Identity management is the process of creating, maintaining and destroying identities of individuals in a population. Biometric technologies are technologies developed to use statistical analysis of an individual’s biological or behavioral traits to determine his identity. Biometrics based authentication systems offer a reliable solution for identity management, because of their uniqueness, relative stability over time and security (among other reasons). Public acceptance of biometric systems will depend on their ability to ensure robustness, accuracy and security. Although robustness and accuracy of such systems are rapidly improving, there still remain some issues of security and balancing it with privacy. While the uniqueness of biometric traits offers a convenient and reliable means of identification, it also poses the risk of unauthorized cross-referencing among databases using the same biometric trait. There is also a high risk in case of a biometric database being compromised, since it’s not possible to revoke the biometric trait and re-issue a new one as is the case with passwords and smart keys. This unique attribute of biometric based authentication system poses a challenge that might slow down public acceptance and the use of biometrics for authentication purposes in large scale applications. In this research we investigate the vulnerabilities of biometric systems focusing on template security in iris-based biometric recognition systems. The iris has been well studied for authentication purposes and has been proven accurate in large scale applications in several airports and border crossings around the world. The most widely accepted iris recognition systems are based on Daugman’s model that creates a binary iris template. In this research we develop different systems using watermarking, bio-cryptography as well as feature transformation to achieve revocability and security of binary templates in iris based biometric authentication systems, while maintaining the performance that enables widespread application of these systems. All algorithms developed in this research are applicable on already existing biometric authentication systems and do not require redesign of these existing, well established iris-based authentication systems that use binary templates.

Memoria para optar al Título Profesional de ingeniero Agrónomo. Mención: Producción Animal / El color de la carne de salmónidos es uno de los parámetros de calidad más importante, pero su medición es compleja. En el presente estudio se evaluaron los sistemas de medición visual (cartilla Roche™ y regla Salmofan) e instrumental (fotocolorímetro triestímulo Minolta Chroma Meter) del color de la carne en salmónidos. Se estudió la precisión (repetibilidad y reproducibilidad) de ambos métodos, la relación entre estos y la relación entre la medición de color con el contenido de pigmento y lípidos. Además, se comparó la variabilidad entre dos fotocolorímetros con distinta área de medición. La precisión de ambos métodos se evaluó en tres plantas de proceso ubicadas en Chiloé, midiendo filetes de trucha arcoíris (Oncorhynchus mykiss) y salmón del Atlántico (Salmo salar) en forma repetida y aleatoria. Las mediciones se hicieron con la luz normal de la planta y luz D65 en cabina de iluminación controlada. El efecto del área de medición de los fotocolorímetros se evaluó sobre filetes de salmón del Atlántico en el centro Colaco de la empresa EWOS S.A. La relación entre contenido de pigmento, de grasa y color se midió en filetes de salmón Coho (Oncorhynchus kisutch) con ambos sistemas en el laboratorio de la empresa CETECSAL S.A. Además se analizó un set de datos de un proyecto FONDEF previo, en el cual se midió color, astaxantina y lípidos en “steaks” de salmón Coho. La repetibilidad del instrumento fue significativamente mayor a la cartilla Roche™ en la medición de trucha arcoíris y salmón del Atlántico. Las mediciones de salmón del Atlántico con regla SalmoFan no presentaron diferencias significativas con el instrumento. La reproducibilidad de la medición visual no presentó diferencias significativas al cambiar operarios ni al variar el tipo de luz. Las correlaciones entre ambos sistemas de medición de color, y de estos con el contenido de astaxantina y lípidos fueron de baja a mediana magnitud fluctuando entre 0 a 0,62, 0,07 a 0,57 y 0,01 a 0,63 respectivamente. Se concluye que la medición de color es un mal predictor del contenido de astaxantina, independiente del método utilizado. El fotocolorímetro de 50 mm de área de medición, para a*, b* y C* presentó una variabilidad (C.V. a* = 6%, b* = 7% y C* = 6%) significativamente menor al de 8 mm (C.V. a* = 20%, b* = 16% y C* = 16%). Para comparar resultados de medición de color, debe tomarse en cuenta el área de medición del fotocolorímetro utilizado, pues estos no son equivalentes. / Visual color with Roche™ card and Roche Salmofan™ ruler was compared with instrumental color (Minolta Chroma Meter™) measured in salmonid fillets. Precision (as repeatability and reproducibility) of methods, relationship between visual and instrumental measurements, and relationship between color, astaxanthin and lipid content were studied. In addition, variability between two colorimeters with different measurement area was compared. Repeatability of instrumental method was significantly higher to Roche ™ card in rainbow trout and Atlantic salmon samples. Measurements of Atlantic salmon fillet using Salmofan™ ruler did not show significant differences with the instrumental color measurements. There was not significant differences in reproducibility of visual measurement in rainbow trout and Atlantic salmon when changing personnel neither when varying illumination source. The relationship between both color systems, and between color systems, astaxanthin and fat content in Coho salmon ranged from low to medium magnitude (0-0.62, 0.07- 0.57 and 0.01-0.63 respectively). It was concluded that fillet color is a bad predictor of astaxanthin content, irrespective of the method used. Colorimeter with 50mm of measurement area, for a*, b* and C* showed a significant smaller variability compared with the 8mm area (C.V. a*=6, b*= and C*=7 v/s C.V. a*=16, b*=16 and C*=20). Measurement colorimeter area must be taken into account in order to compare results of color measurement .