The aim of the present thesis is to give a comparision on sex determination of phenotypically undifferentiated birds species focused on the Long-eared Owl (Asio otus). Compared to other species of owls is relatively a few researches on the Long-eared Owl and researches on sex differences have not led to the quantified results yet. Attention is focused on characteristics and mechanisms of birds coloration. This work includes the methods and results of colour perception and interpretation in sexual dimorphism. It focuses primarily on the differences in color of certain parts of the bird, such as the alula, secondary remiges and lower part of the wing. For those pieces is further evaluating color differences in sex and proposes solutions that could help in further researches on sex determination of the Long-eared Owl.

One of the main objectives in digital imaging is to mimic the capabilities of the human eye, and perhaps, go beyond in certain aspects. However, the human visual system is so versatile, complex, and only partially understood that no up-to-date imaging technology has been able to accurately reproduce the capabilities of the it. The extraordinary capabilities of the human eye have become a crucial shortcoming in digital imaging, since digital photography, video recording, and computer vision applications have continued to demand more realistic and accurate imaging reproduction and analytic capabilities. Over decades, researchers have tried to solve the colour constancy problem, as well as extending the dynamic range of digital imaging devices by proposing a number of algorithms and instrumentation approaches. Nevertheless, no unique solution has been identified; this is partially due to the wide range of computer vision applications that require colour constancy and high dynamic range imaging, and the complexity of the human visual system to achieve effective colour constancy and dynamic range capabilities. The aim of the research presented in this thesis is to enhance the overall image quality within an image signal processor of digital cameras by achieving colour constancy and extending dynamic range capabilities. This is achieved by developing a set of advanced image-processing algorithms that are robust to a number of practical challenges and feasible to be implemented within an image signal processor used in consumer electronics imaging devises. The experiments conducted in this research show that the proposed algorithms supersede state-of-the-art methods in the fields of dynamic range and colour constancy. Moreover, this unique set of image processing algorithms show that if they are used within an image signal processor, they enable digital camera devices to mimic the human visual system s dynamic range and colour constancy capabilities; the ultimate goal of any state-of-the-art technique, or commercial imaging device.

A Catarata Congênita (CC) é definida como a opacidade do cristalino, que está presente no nascimento ou surge logo após. Pode ser classificada de acordo com sua morfologia, posição, densidade e seu prognóstico varia conforme a morfologia e precocidade do diagnóstico e tratamento. Devido à privação visual na Catarata Congênita, ocorre o impedimento da evolução orgânica e funcional de maneira adequada do sistema visual, levando a alterações que resultam na baixa visão, além afetar componentes da retina e áreas do cérebro relacionados com o processamento de cores. O objetivo deste trabalho foi verificar o impacto da no desenvolvimento da visão de cores e acuidade visual entre crianças tratadas da catarata congênita. Foram avaliados 2 grupos: 16 crianças do grupo controle e 16 crianças do grupo CC. Foi utilizado os Cartões de Acuidade de Teller para avaliar a acuidade visual e uma versão adaptada para avaliação de crianças do Cambridge Colour Test (CCT) para a avaliação dos três eixos de visão de cores (protan, deutan e tritan). Houve redução de Acuidade visual de todas as crianças do grupo CC além de redução nos eixos deutan e protan quando comparados com o grupo controle, principalmente o eixo protan. Foi encontrada correlação entre o eixo protan e acuidade visual, inferindo assim que há uma alteração na retina central e na via parvocelular em crianças com CC / Congenital Cataracts (CC) is defined as lens opacity, present at birth or appearing soon after. This condition can be classified according to morphology, position and density, and the prognosis varies according to morphology and early diagnosis and treatment. Due to visual deprivation in Congenital Cataracts, the organic and functional evolution of the visual system is impaired, leading to changes that result in poor vision, while also affecting retina components and brain areas related to color processing. The aim of this study was to verify the impact on the development of color vision and visual acuity among children who underwent congenital cataracts treatment. Two groups were evaluated: 16 children in the control group and 16 in the CC group. Teller\'s Acuity Cards were used to evaluate visual acuity, and an adapted version of the Cambridge Color Test (CCT) was applied to evaluate the three color vision axes (protan, deutan and tritan). Decreased visual acuity was observed for all children in the CC group, as well as in the deutan and protan axes when compared to the control group, primarily the protan axis. A correlation was detected between the protan axis and visual acuity, thus inferring that changes in the central retina and the parvocellular pathway in children with CC do indeed occur

Zunächst wurden mit Hilfe eines neuen Injektionssystems die Vorteile der Bolusgabe und der kontinuierlichen Applikation d-galaktosehaltiger Ultraschallsignalverstärker kombiniert und an einem klein- (Æ 0,86mm) und einem großlumigen (Æ 16 mm) Gefäßmodell die optimale Basis- und Bolusflußratenkombination für die Powerdopplersonographie evaluiert. Der Powerdopplersignalintensitätsverlauf verschiedener Infusionsprotokolle wurde subjektiv von drei Beobachtern einer sechsstufigen Skala zugeordnet. Objektive Intensitätsmeßdaten wurden mit einer CW-Dopplersonde und einem Computersystem gewonnen. Die 1 ml/min.-Basisinfusionsrate kam dem Optimalzustand am nächsten (Großlumenmodell: 70 %, Kleinlumenmodell: 100 % Grad-4-Plateau trotz geringer Standardabweichung der mittleren Spektraldopplerverstärkungsmeßwerte im Plateaubereich). Sie ermöglichte eine annähernd optimale Gefäßdarstellung mit ausreichendem Spielraum für mehrfache, optisch gut wahrnehmbare Bolusgaben (Optimalbolus: 300mg/ml, 2 ml/s, 1 s Injektionsdauer). Diese Ergebnisse lassen eine medizinische und ökonomische Optimierung des Signalverstärkereinsatzes in der Powerdopplersonographie erwarten. Anhand von tierexperimentellen Untersuchungen wurde die Zuverlässigkeit der nativen und der signalverstärkten Farbdopplersonographie bei der Visualisierung der intratumorösen Angioneogenese im Vergleich zur histologischen Vaskularisationsquantifizierung evaluiert. Zu diesem Zweck wurden Melanomzellen des Typs B16-F1 Mäusen intra- bzw. subkutan imjiziert und nach einer Wachstumsperiode in 54 Fällen sonographisch im B-Modus bezüglich Größe, Homogenität, Echogenität und Grenzechoschärfe und in der Farbdopplersonographie bezüglich intratumorös erkennbarer Gefäßzahl, Gefäßarchtektur und Gefäßanteil an der Tumorquerschnittsfläche (= percentage vessel area, PVA) analysiert. Die anschließende histologische Aufarbeitung erbrachte Vergleichsdaten hinsichtlich Größe, Nekrotisierung und Vaskularisation der Tumoren. Es fand sich eine signifikante Korrelation (p < 0,01) zwischen den makroskopisch und den sonographisch ermittelten Tumordurchmessern, jedoch zwischen Histologie und Sonographie bezüglich sonographisch erkannter Nekrosen nur, wenn diese mehr als 40 % des Tumors erfaßten. Nach Signalverstärkerapplikation stiegen die sonographisch erkennbare Tumorgefäßzahl, -architektur und die PVA signifikant an (p < 0,01), letztere bei den intrakutanen Tumoren um 483 % und bei den subkutanen um 373 %. Der histologische Vaskularisationsgrad korrelierte am stärksten (r = 0,686) von allen Farbdopplerparametern mit der signalverstärkten PVA (p < 0,01). Somit trug die Signalverstärkergabe zur Verbesserung der Korrelation der Ergebnisse der sonographischen und histologischen Vaskularisations- und Angioneogenesebeurteilung bei. Im klinisch-experimentellen Teil wurde prospektiv bei 83 malignitätssuspekten, kutan oder subkutan lokalisierten Raumforderungen unterschiedlichen, meist epithelialen Ursprungsgewebes mittels nativer und signalverstärkter Farbduplexsonographie eine Dignitätseinschätzung vorgenommen. Als Einstufungskriterien wurden diverse B-Modus- und Farbdopplerkriterien, u.a. intratumorös erkennbare Gefäßzahl und PVA, verwendet. Die Diagnosesicherung erfolgte durch Histologie oder Verlaufskontrolle. Während weder die B-Modus-Kriterien noch die Dopplerspektralanalyse für die Dignitätseinschätzung geeignet erschienen, trugen die Farbdopplerparameter und besonders die PVA nach Signalverstärkergabe zur Dignitätsbestimmung bei, wobei die erkennbare Gefäßzahl nach Signalverstärkergabe signifikant (p < 0,01) zunahm. Als ungeeignet erwiesen sich diese Kriterien jedoch bei entzündlichen und angiomatösen Raumforderungen und epithelialen Rezidivtumoren. Insgesamt liefert die signalverstärkte Farbdopplersonographie wesentliche zusätzliche Informationen bezüglich Angioneogenese und Dignität von Raumforderungen der Haut und ihrer Anhangsgebilde, insbesondere die signalverstärkte semiquantitative Vaskularisationsanalyse. Sie ist der B-Modus-Sonographie und der Spektraldoppleranalyse überlegen. Die Signalverstärkergabe führt zu einer deutlichen Sensitivitätserhöhung. / A new injection system combines the advantages of bolus and of continuous application of ultrasound contrast agents. This study evaluated the optimal combination of basic and bolus flow rates in power Doppler sonography using two different types of vitro vessel models. The flow of an in vitro circulation model consisting of a wide or small lumen vessels was visualized by power Doppler ultrasound. The intensity of colour Doppler signal was assessed subjectively by three observers using a six step scale (optimal: degree 5). The objective signal intensity was measured by a CW-Doppler probe and a computed sytem. Using a basic flow rate of 1 ml/min., approximately optimal results were reached. This basic flow rate enabled an almost optimal visualization of the vessel lumen with sufficient free range for repeated, well visible bolus injections. Thus, the use of the new injection system combining bolus and continous injection of contrast agent improves medical and economic use of signal enhancing agents in power Doppler sonography. The aim of the next study was to evaluate the reliability of plain and enhanced colour Doppler sonography in visualization of intratumoral vascularization as a sign of malignant angioneogenesis. Therefore, malignant melanomas of the histological type B16-F1 which had been implanted in mice were examined by sonography. The majority of these tumours was localized intracutaneously, the minority subcutaneously. Various B-mode aspects, colour Doppler criteria, and spectral Doppler parameter were evaluated before and after i.v.-application of an ultrasound signal enhancer. After sonographic examination, all tumors were analyzed histologically with semiquantitative grading of tumoral vascularization. Despite the higher mean volume of the subcutaneous tumours, the percentage of tumors with visible intratumoral vessels was not higher than in intracutaneous tumors on plain images. Enhanced, the sonographical vascularization of subcutaneous tumors seemed to be superior to this of the intracutaneous. The signal enhanced mode was definitely superior to plain Doppler in showing the intratumoral vessels as a sign of angioneogenesis. The intratumoral vascular structure could be sufficiently analyzed the minority of all tumors by plain Doppler, but in more than 90 % after application of the signal enhancing agent. Intracutaneous tumors had a more compact vascular structure than subcutaneous. Despite the missing direct correlation between the sonographically and the histologically determined degree of tumour vascularization the correlation was improved after application of the signal enhancer. Only the enhanced colour Doppler sonography provides valuable noninvasive information about angioneogenetic hypervascularization in experimental melanomas. The third study evaluated colour Doppler criteria to differentiate between malignant and benign skin tumors determining the extent of the intratumorous vascularization. The B-mode sonomorphology and the extent of the vascularization in color Doppler of clinically potentially malignant tumours of the cutaneous and subcutaneous structures were analyzed and quantified by different methods. After application of the signal enhancing agent, counting the intratumoral vessels visible on one ultrasound slice led to the highest sensitivity of all used criteria but the specificity was poor. The highest specificity and diagnostic accuracy of all used criteria were obtained using the criterion "percentage vessel area > 5,0 %" after excluding all inflamed lesions by clinical aspects. Plain colour Doppler increased the specificity but the sensitivity decreased to a not acceptable level. The analysis of the B-mode morphology and spectral Doppler parameter of intratumoral vessels did not contribute to differential diagnosis. Signal enhanced colour Doppler sonography is a valuable tool in pretherapeutic assessment of cutaneous lesions. This method can be relevant for therapy and prognosis. The application of the signal enhancing agent increases significantly (p < 0.01) the sensitivity. This method is not useful in assessing benignity or malignancy of inflamed lesions and angiomas.

O objetivo deste trabalho foi analisar o uso da cor em ambientes internos industriais, sendo regidos por legislação e normatização específicas, uma vez que envolvem atividade de trabalho humano. Numa primeira etapa é apresentada pesquisa bibliográfica com intuito de caracterizar as exigências legais que definem o uso da cor para estes ambientes. Identifica-se a legislação relacionada à Segurança do Trabalho, de abrangência nacional -- em conformidade com o Ministério do Trabalho e Emprego; e outras de abrangência mais restrita. Por exemplo, o contexto estadual de São Paulo, que disciplina orientações do Corpo de Bombeiros e Centro de Vigilância Sanitária da Secretaria de Estado da Saúde. Sob a ótica da Segurança do Trabalho, são avaliadas a aplicação de cores em: máquinas, equipamentos, elementos construtivos, indicação de localização de equipamentos e sinalização de segurança. O uso de vários matizes para situações distintas propicia ao trabalhador o reconhecimento de vários cenários por meio de padronização de informação; possibilitando-lhe tomar ciência da presença de um material e os riscos e perigos a ele relacionados. Paralelamente, o presente estudo compreendeu pesquisa de campo para efeito de registros fotográficos de ambientes de trabalho: isto foi feito para exemplificar os tópicos estudados. Ao considerar a presença do trabalhador, percebe-se que entender visão de cores torna-se primordial para melhor avaliar a eficácia da sinalização e de outras informações relativas à cor existentes no ambiente de trabalho. Assim, foram analisadas a resposta fisiológica do organismo diante da cor para pessoas de visão normal e exigências relativas às atividades ou tarefas desempenhadas pelo trabalhador em condições de exposição à sinalização. Neste percurso foram ainda verificados aspectos relativos à classificação e nomenclatura das cores. Como resultado, a análise sustentou -- ou não --a aplicação de determinado matiz para situações específicas. Nas considerações finais, o foco está na obrigatoriedade do uso da cor relacionado à Segurança e a sinalização recomendada para advertir sobre os riscos existentes, sem considerar a particularidades das atividades e tarefas a serem desempenhadas e as características de cada indivíduo. Conclui-se que quanto mais informação houver a respeito dos agentes que compõem um determinado sistema, mais assertivamente será possível indicar soluções de aplicação de cor no ambiente de trabalho. / The objective of this work was to analyze the usage of colour at industrial environments which follow strict rules because there are workers involved in. At first a bibliographical research was developed to recognize the legal requirement that define the use of colours in such environments. There are rules related to Occupational Safety that are mandatory nationwide, according to the Ministry of Labor and Employment, and other rules which are more restrict. For example, in the State of Sao Paulo, there are rules that instruct the Fire Department and the Health Surveillance Center. Under the perspectives of Occupational Safety, the use of colours on machines, equipments, building components and safety systems and principles of signaling were evaluated. The use of hues in different situations enables the worker the recognition sceneries due to the standardized information, making him be aware of the presence of a certain material and the risks and hazard that are related to it. This work also embodied a practical research to take photographs of different work rooms to show the studied topics. When the presence of a worker is considered, it is possible to realize that understanding about colour vision is essential to verify signallig performance and more information about colour where people work. So, the physiological answers to colour were studied considering people with normal vision and their necessary behaviour in certain situations that involved signaling while they were working. During this study the qualification of colours and their given names were verified. As a result, the analysis sustained - or not - the application of a certain hue in a certain situation. In the final analysis the focus was on the compulsory use of colour related to Occupational Safety and the recommended signaling to advise workers against existing risks without considering the specific aspect of each task that a worker can develop and his particular characteristics. The conclusion shows that the more available information a professional can get about a system, the more assertive solutions about the use of colour at work environment will be reached.

Atualmente o digluconato de clorexidina (CHX) constitui o agente antimicrobiano de uso bucal mais utilizado na Odontologia devido ao seu amplo espectro de ação contra bactérias, fungos e vírus e efeito residual. No entanto, este agente apresenta efeitos colaterais quando utilizado por longo período, podendo causar coloração extrínseca nos dentes e restaurações, alteração no paladar, sensibilidade na língua e descamação das mucosas. Estes efeitos adversos conduzem à pesquisa de novas formulações. Entretanto, até o momento, nenhum agente antimicrobiano substituiu a clorexidina. Assim, o objetivo deste estudo foi desenvolver uma nova formulação antimicrobiana à base de um extrato de planta derivado do chá verde, a epigalocatequina-3-galato (EGCG), avaliar sua ação antimicrobiana contra microrganismos cariogênicos, in vitro e in vivo, e a possibilidade de alteração de cor dental, in vitro. A atividade antimicrobiana in vitro contra S. mutans, S. sobrinus e L. casei foi avaliada por meio da determinação da concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM), e, posteriormente sua concentração antimicrobiana de uso clínico foi determinada in vivo, após seu uso por crianças com alto risco e atividade da doença cárie. A concentração de microrganismos cariogênicos foi determinada na saliva das crianças, antes e após a realização do bochecho em diferentes concentrações, até se obter a máxima ação antimicrobiana. A clorexidina a 0,12% (Periogard®) e a água destilada foram utilizadas como controle positivo e negativo, respectivamente. A possível alteração de cor dental foi avaliada na coroa de dentes decíduos e permanentes humanos anteriores recém-extraídos, por meio de espectrofotometria (Easy Shade) e obtenção dos valores absolutos de L*, a* e b* (Sistema CIELab). Foi determinada a cor inicial e após a realização de 1, 5, 10 e 30 simulações de bochechos com cada solução testada durante 1 minuto. Os resultados dos ensaios de CIM e CBM in vitro mostraram que a formulação de EGCG inibiu o crescimento de todos os microrganismos cariogênicos avaliados. A CIM de EGCG contra S. mutans, S. sobrinus e para o L. casei foi obtida nas concentrações de 125, 750 e 750 &mu;g/mL, respectivamente. A CBM de EGCG contra o S. mutans, S. sobrinus e para o L. casei foi verificada nas concentrações de 250, 1000 e 1000 &mu;g/mL, respectivamente. A CBM em comum entre os 3 microrganimos foi utilizada como concentração inicial para a avaliação da atividade antimicrobiana in vivo. A partir desse valor a concentração foi sendo dobrada até atingir o valor de 4000 &mu;g/mL, que foi considerada a concentração de EGCG de uso clínico que causou redução da microbiota salivar cariogênica (86,48%) que mais se assemelhou à clorexidina (89,89%). A simulação de bochechos com a formulação de EGCG desenvolvida (4000 &mu;g/mL) causou alteração no valor absoluto das coordenadas L*, a* e b* em dentes decíduos e permanentes, de forma semelhante à causada pela solução de clorexidina. A alteração dos valores absolutos de L* e b* foram reversíveis após a realização de profilaxia dental. Com base nas metodologias e nos resultados obtidos no presente estudo pode-se concluir que a formulação desenvolvida, à base de EGCG, apresenta efeito antimicrobiano contra microrganismos cariogênicos, in vitro e in vivo, e causa alteração de cor dental reversível. / Currently the digluconate of chlorhexidine (CHX) is the antimicrobial agent for oral use most often used in dentistry due to its broad spectrum of activity against bacteria, fungi and viruses, and residual effect. However, this agent has side effects when used for long periods, and may cause extrinsic staining on teeth and restorations, change in taste, tenderness in the language and peeling of the mucous membranes. These adverse events lead to research into new formulations. However, to date, no antimicrobial agent has replaced the chlorhexidine. The objective of this study was to develop a new antimicrobial formulation based of green tea extract, epigallocatechin-3-gallate (EGCG), evaluate their antimicrobial activity against cariogenic microorganisms in vitro and in vivo, and possibility of dental color change in vitro. The in vitro antimicrobial activity against S. mutans, S. sobrinus e L. casei was evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and subsequently its antimicrobial concentration was determined in clinical use, after its use for children at high risk and activity of caries. The concentration of cariogenic microorganisms was determined in the saliva of children before and after performing the mouthwash at different concentrations to obtain maximum antimicrobial activity. The chlorhexidine 0.12% (Periogard®) and distilled water were used as positive and negative controls, respectively. The possible dental color change was evaluated on the crown of deciduous and permanent teeth freshly extracted human anterior by means of spectrophotometry (Easy Shade) and obtaining the absolute values of L *, a * and b * (CIELab system). The color was determined in the beginning and after the completion of 1, 5, 10 and 30 mouthwash simulations for 1 minute of each solution tested. In vitro results of MIC and CBM tests showed that formulation EGCG inhibited the growth of all cariogenic microorganisms evaluated similarly to chlorhexidine. The MIC of EGCG against S. mutans, S. sobrinus and L. casei was observed at concentrations of 125, 750 and 750 &mu;g/ml, respectively. EGCG MBC against S. mutans, S. sobrinus and L. casei was observed at concentrations of 250, 1000 and 1000 &mu;g/ml, respectively. The common CBM between the three microbes was used as initial concentration for the evaluation of the antimicrobial activity in vivo. From this value the concentration was being folded up to the value of 4000 &mu;g/mL, which was considered the concentration of EGCG clinical use which caused reduction in salivary microbiota cariogenic (86.48%) that most resembled the chlorhexidine (89.89%). The simulation of mouthwash with the developed formulation EGCG (4000 &mu;g/ml) caused change in the absolute value of the coordinates L *, a * and b * in deciduous and permanent teeth, similar to that caused by chlorhexidine . The changes of the absolute values of L* and b* were reversible after performing dental prophylaxis. Accordance with the procedures and the results obtained in this study it can be concluded that the formulation developed, based on EGCG, has antimicrobial effect against cariogenic microorganisms in vitro and in vivo, and causes reversible change dental color.

Atualmente o digluconato de clorexidina (CHX) constitui o agente antimicrobiano de uso bucal mais utilizado na Odontologia devido ao seu amplo espectro de ação contra bactérias, fungos e vírus e efeito residual. No entanto, este agente apresenta efeitos colaterais quando utilizado por longo período, podendo causar coloração extrínseca nos dentes e restaurações, alteração no paladar, sensibilidade na língua e descamação das mucosas. Estes efeitos adversos conduzem à pesquisa de novas formulações. Entretanto, até o momento, nenhum agente antimicrobiano substituiu a clorexidina. Assim, o objetivo deste estudo foi desenvolver uma nova formulação antimicrobiana à base de um extrato de planta derivado do chá verde, a epigalocatequina-3-galato (EGCG), avaliar sua ação antimicrobiana contra microrganismos cariogênicos, in vitro e in vivo, e a possibilidade de alteração de cor dental, in vitro. A atividade antimicrobiana in vitro contra S. mutans, S. sobrinus e L. casei foi avaliada por meio da determinação da concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM), e, posteriormente sua concentração antimicrobiana de uso clínico foi determinada in vivo, após seu uso por crianças com alto risco e atividade da doença cárie. A concentração de microrganismos cariogênicos foi determinada na saliva das crianças, antes e após a realização do bochecho em diferentes concentrações, até se obter a máxima ação antimicrobiana. A clorexidina a 0,12% (Periogard®) e a água destilada foram utilizadas como controle positivo e negativo, respectivamente. A possível alteração de cor dental foi avaliada na coroa de dentes decíduos e permanentes humanos anteriores recém-extraídos, por meio de espectrofotometria (Easy Shade) e obtenção dos valores absolutos de L*, a* e b* (Sistema CIELab). Foi determinada a cor inicial e após a realização de 1, 5, 10 e 30 simulações de bochechos com cada solução testada durante 1 minuto. Os resultados dos ensaios de CIM e CBM in vitro mostraram que a formulação de EGCG inibiu o crescimento de todos os microrganismos cariogênicos avaliados. A CIM de EGCG contra S. mutans, S. sobrinus e para o L. casei foi obtida nas concentrações de 125, 750 e 750 &mu;g/mL, respectivamente. A CBM de EGCG contra o S. mutans, S. sobrinus e para o L. casei foi verificada nas concentrações de 250, 1000 e 1000 &mu;g/mL, respectivamente. A CBM em comum entre os 3 microrganimos foi utilizada como concentração inicial para a avaliação da atividade antimicrobiana in vivo. A partir desse valor a concentração foi sendo dobrada até atingir o valor de 4000 &mu;g/mL, que foi considerada a concentração de EGCG de uso clínico que causou redução da microbiota salivar cariogênica (86,48%) que mais se assemelhou à clorexidina (89,89%). A simulação de bochechos com a formulação de EGCG desenvolvida (4000 &mu;g/mL) causou alteração no valor absoluto das coordenadas L*, a* e b* em dentes decíduos e permanentes, de forma semelhante à causada pela solução de clorexidina. A alteração dos valores absolutos de L* e b* foram reversíveis após a realização de profilaxia dental. Com base nas metodologias e nos resultados obtidos no presente estudo pode-se concluir que a formulação desenvolvida, à base de EGCG, apresenta efeito antimicrobiano contra microrganismos cariogênicos, in vitro e in vivo, e causa alteração de cor dental reversível. / Currently the digluconate of chlorhexidine (CHX) is the antimicrobial agent for oral use most often used in dentistry due to its broad spectrum of activity against bacteria, fungi and viruses, and residual effect. However, this agent has side effects when used for long periods, and may cause extrinsic staining on teeth and restorations, change in taste, tenderness in the language and peeling of the mucous membranes. These adverse events lead to research into new formulations. However, to date, no antimicrobial agent has replaced the chlorhexidine. The objective of this study was to develop a new antimicrobial formulation based of green tea extract, epigallocatechin-3-gallate (EGCG), evaluate their antimicrobial activity against cariogenic microorganisms in vitro and in vivo, and possibility of dental color change in vitro. The in vitro antimicrobial activity against S. mutans, S. sobrinus e L. casei was evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and subsequently its antimicrobial concentration was determined in clinical use, after its use for children at high risk and activity of caries. The concentration of cariogenic microorganisms was determined in the saliva of children before and after performing the mouthwash at different concentrations to obtain maximum antimicrobial activity. The chlorhexidine 0.12% (Periogard®) and distilled water were used as positive and negative controls, respectively. The possible dental color change was evaluated on the crown of deciduous and permanent teeth freshly extracted human anterior by means of spectrophotometry (Easy Shade) and obtaining the absolute values of L *, a * and b * (CIELab system). The color was determined in the beginning and after the completion of 1, 5, 10 and 30 mouthwash simulations for 1 minute of each solution tested. In vitro results of MIC and CBM tests showed that formulation EGCG inhibited the growth of all cariogenic microorganisms evaluated similarly to chlorhexidine. The MIC of EGCG against S. mutans, S. sobrinus and L. casei was observed at concentrations of 125, 750 and 750 &mu;g/ml, respectively. EGCG MBC against S. mutans, S. sobrinus and L. casei was observed at concentrations of 250, 1000 and 1000 &mu;g/ml, respectively. The common CBM between the three microbes was used as initial concentration for the evaluation of the antimicrobial activity in vivo. From this value the concentration was being folded up to the value of 4000 &mu;g/mL, which was considered the concentration of EGCG clinical use which caused reduction in salivary microbiota cariogenic (86.48%) that most resembled the chlorhexidine (89.89%). The simulation of mouthwash with the developed formulation EGCG (4000 &mu;g/ml) caused change in the absolute value of the coordinates L *, a * and b * in deciduous and permanent teeth, similar to that caused by chlorhexidine . The changes of the absolute values of L* and b* were reversible after performing dental prophylaxis. Accordance with the procedures and the results obtained in this study it can be concluded that the formulation developed, based on EGCG, has antimicrobial effect against cariogenic microorganisms in vitro and in vivo, and causes reversible change dental color.

Cette thèse interroge et analyse comment la lumière, en tant que phénomène naturel et physique, est devenue un phénomène proprement pictural. Si la lumière, qu’elle soit naturelle ou artificielle, est la force mettant en acte la visibilité du monde pour la majorité des êtres vivants, elle est également à l’origine des couleurs qui sont les effets de son action spécifique sur l’œil. En interagissant directement avec la matière, la lumière produit la couleur et penser philosophiquement le concept de lumière dans l’art pictural revient donc tout d’abord à comprendre le cheminement des voies propres de la couleur qui fut progressivement reconnue comme la spécificité même de la peinture. Intrinsèquement liées au sein de toute expérience perceptive, lumière et couleur impliquent un processus physiologique dont les paradigmes évoluèrent au fil des siècles. La couleur révèle un monde visible dont l’origine lumineuse échappe pourtant à la perception et les peintres œuvrèrent à dégager l’origine invisible du visible : la lumière, essence de la visibilité. Le sujet percevant, découvert comme l’agent actif de l’expérience optique impliqua une transformation radicale et le monde du visible, qui constituait jusqu’alors une forme privilégiée de connaissance, fut reconsidéré en fonction des caractéristiques subjectives de l’œil. En devenant objet de connaissance, la vision pénétra ainsi dans le champ de la philosophie et des sciences expérimentales. C’est plus particulièrement à travers l’analyse de l’œuvre de Mark Rothko et de celle de Pierre Soulages que nous orienterons la seconde partie de notre recherche tant le concept de lumière y rencontre de riches problématiques esthétiques qui entrent en résonance avec les paradigmes artistiques propres à l’histoire de la peinture. / This doctoral thesis suggests questionning how light, a natural and physical phenomenon has also become a concept in the field of painting. Light, artifical or natural, is not only the mere driving force behind vision for the majority of beings in this world, it is also at the origin of colors, which result from the action of light on the eye. By interacting directly with the material, light produces color. Therefore, to think philosophically the concept of light in pictorial art would thus means first to understand the inner ways of color, which have been gradually recognized as the true specificity of painting. Intrinsically connected within any perceptive experience, light and color involve a physiological process paradigm which evolved in the course of the centuries. Color reveals a visible world whose bright origin still cannot be grasped by our perception, and painters have worked to release the invisible origin of the visible: light, the essence of the visibility. The role of the perceiving subject is then profoundly transformed as it becomes regarded as the active agent of the optical experience. The visible world, thus far a privileged shape of knowledge, is reconsidered according to the subjective characteristics of the eye. By becoming an object of knowledge, vision became associated to the fields of philosophy and experimental sciences. Most precisely, since the concept of light meets in their works such rich aesthetic problems which resonate with the artistic paradigms that belong to the history of painting, it is throughout an analysis of Mark Rothko’s and Pierre Soulages’s work that the research work has been focused in a second part.

It is well known that the colour preferences of ganglion and LGN cells do not match the four perceptually simple colours red, green blue and yellow. It is also known that although colour perception is distorted in the peripheral visual field, there are four hues that appear stable with eccentricity. These are defined as peripherally invariant hues. Both of these observations must in some way reflect the physiological substrate of neurons at different stages of the primary visual pathway. The experiments described here are aimed at understanding the link between the physiology and the perception of colour by studying the characteristics of peripheral colour visionThe following questions have been addressed; i) to what extent does colour matching rely on the retinal physiological substrate? ii) what is the reason for the discrepancy between invariant and unique green and how is cone contrast linked to this paradox? iii) how are the `special' hues (invariant and unique) related to human evolution? iv) how does peripheral colour vision vary between males and females?An asymmetric colour matching paradigm and a colour naming task have been employed. In the colour matching task, 24 chromatic axes of variable purity are used. Observers match the chromaticity of a 3 degree peripheral spot with that of a 1 degree parafoveal spot. The results are expressed in terms of hue rotation, saturation match and cone contrast. In the colour naming experiment the observers name 40 chromatic axes as either red, blue, green or yellow and colour naming functions are derived. The central maxima of these functions are defined as the unique hues. The results suggest that colour matching and cone opponency reflect the characteristics of the retinal neural network as they exhibit nasal-temporal asymmetries, similar to known physiological asymmetries. Although three of the peripherally invariant hues match the unique counterparts, invariant and unique green are markedly different for all observers. In an important control experiment unique hues are shown to be stable with eccentricity and purity. This confirms that these attributes are not confounding factors for the observed discrepancy between invariant and unique green. Unlike for the other 'special' hues the RMS cone contrast of invariant green differs markedly between parafoveal and peripheral targets. It is likely that the cone contrast remains unchanged only if the stimuli excite the same number of cones. Two invariant and two unique hues (blue and yellow) fall on the daylight locus suggesting that discrimination in these regions of the colour space is strongly influenced by terrestrial illumination. Moreover, the inter-individual variability is found to be minimised around the daylight locus showing that the blue-yellow system is more stable across colour normal populations than the red-green system. A statistically significant difference is demonstrated between the peripheral colour vision of males and females. This may be attributed to the M-cone polymorphism which in addition to X-chromosome inactivation, results in more than three cone types in the female retina.

Cet écrit traverse l'encre de la peinture par la sienne propre. Elle a ce corps en partage, à la fois fraternel et inconciliable. L'encre de l'écrit a voulu ici se frayer un chemin de liquidité dans la peinture, donnant à son mouvement l'ébranlement de la couleur, qui est un geste de la matière elle-même. Mon geste, lui, bu par le papier et retiré dans des plis de vagues, opère un glissement jusqu'au blanc d'une page sur la table qui se déploie jusqu'à cet objet singulier qu'est la thèse en arts. De fait, comme la peinture accompagne dans son sillage d'ombres le questionnement d'un regard, son itinéraire sans tracé, l'écrit depuis la peinture, se retourne sur son propre objet — d'une encre à l'autre. La construction d'une parole en prise avec une errance d'atelier est délicate. Elle mêle son corps résonant d'images à celui des mots des poètes, travaillant un langage inconnu au creux de l'impasse même que constituent les mots, la prise de parole. La voix du peintre est la seule que je connaisse. Elle est issue de l'abandon et du dessaisissement à l’œuvre. Elle engage la pensée dans le faire, au milieu d'une déposition qui est celle, multiple, d'un corps d'encre, d'une peinture en éclat, d'un geste et sa dépose, d'une voix et de ses fragments. La déposition appelle le sol. C'est bien de ce sol dont il est question tout au long de cet écrit. Un fondement, comme fondation mais aussi comme ce qui fond sous les pas. Liquide, fluide, mouvante. Une déprise qui est aussi un ancrage, une attache qui est aussi un débord. / This writing goes through the ink of painting through its own. It has this body to share, both fraternal and irreconcilable. Here the ink of writing sought to pave a liquid way in painting, giving to its movement the trembling of color, which is a gesture of matter itself. As for my gesture, drunk by the paper and withdrawn in folds of waves, operates a drift to the white of a page on the table, that unfolds to this singular object that is the thesis in fine arts. In fact, as painting accompanies in its shadowy wake the questioning of a gaze, its course without outline, writing from painting, turns on its own object - from one ink to another. The construction of a discourse in touch with the wandering of the studio is delicate. It merges its body resonant with images with that of words from poets, working an unknown language in the very core of the impasse that constitutes words, access to speech. The painter's voice is the only one I know. It is the result of the abandonment and divestment at work. It engages thought in making, in the midst of a deposition which is, multiple, that of a body of ink, of a radiant painting, of a gesture and its removal, of a voice and its fragments. Deposition calls for the ground. It is that very ground that is being discussed throughout this writing. A grounding, as foundation but also as what melts under the steps. Liquid, fluid, moving. A release that is also an anchor, a tie that is also an overflow.