829 resultados para color difference
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http://digitalcommons.winthrop.edu/dacusfocus/1023/thumbnail.jpg
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Durante o exercício, indivíduos com diabetes tipo 1 podem necessitar um aporte maior de carboidratos (CHO), do que os contidos nas bebidas esportivas, para manter os níveis de glicose sanguínea. OBJETIVO: Verificar a resposta glicêmica em adolescentes diabéticos tipo 1, durante 60 minutos e após 60 minutos do término de exercício submáximo (55-65% do VO2max) em ciclo ergômetro em 2 situações: (1) com a utilização de bebida carboidratada a 8% (CHO 8%) e (2) com a utilização de bebida carboidratada a 10% (CHO 10%). MÉTODOS: Dezesseis adolescentes (10 meninos e 6 meninas – 16,25 ± 2,65 anos), com diabetes tipo 1 controlada (HbA1c< 7,31%) e sem complicações da doença, pedalaram a 55-65% do VO2max por 60 min em dois dias separados. Os sujeitos ingeriram tanto a bebida com CHO 8% como a CHO 10% (2,62 g e 3,28 g de frutose; e 5,38 g e 6,72 g de glicose em 100 ml, respectivamente) em cada uma das duas sessões de exercício. As duas bebidas eram similares na cor e no sabor. O volume ingerido das bebidas foi de 5 ml·kg-1 15 min antes do exercício, e 2 ml·kg-1 a cada 15 min de exercício, oferecidos de forma randomizada e duplo-cega. RESULTADOS: Após 60 min de bicicleta, houve uma redução não significativa de 20,06 mg·dL-1 (p>0,05) e a manutenção (-0,533 mg·dL- 1)(p>0,05) da glicemia capilar com a ingestão das bebida CHO 8% e CHO 10%, respectivamente. Durante o exercício, a diferença entre os deltas das bebidas também não foi significativa (p=0,056). No período de recuperação, não foram encontradas diferenças significativas na glicemia entre as sessões. Também não foram encontradas diferenças significativas entre as sessões na freqüência cardíaca, taxa de percepção ao esforço, peso pré e pós-exercício e nos sintomas gastrointestinais. CONCLUSÃO: A ingestão de bebida contendo 8% e 10% de CHO preveniu uma redução significativa na glicemia induzida por uma hora de exercício contínuo em adolescentes com diabetes tipo 1.
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O objetivo do estudo foi avaliar as características da dentina cariada remanescente de molares decíduos quanto à coloração, consistência e microdureza, após um período médio de 3 anos e 8 meses da realização do capeamento pulpar indireto. O estudo clínico constou de 27 dentes que apresentavam lesões cariosas ativas com expressão radiográfica em metade interna de dentina. Aleatoriamente, foi realizado o capeamento pulpar indireto e utilizado como material capeador o hidróxido de cálcio (HC) e o cimento de ionômero de vidro resinoso modificado (CIVRM). As crianças foram acompanhadas através de exames clínicos e radiográficos, e ao longo de um período médio de 3 anos e 8 meses, observou-se um índice de sucesso de 89% para o grupo do HC e de 93% para o CIVRM, não havendo diferença estatisticamente significante entre os dois grupos (p=0,62). Os dentes considerados como sucesso no estudo clínico foram agrupados em um único grupo (grupo teste), que constou de 13 dentes que sofreram esfoliação natural ou exodontia por motivos ortodônticos. Além disso, foram selecionados 15 molares decíduos hígidos (grupo controle positivo) e 15, portadores de lesões cariosas ativas em metade interna de dentina (grupo controle negativo). As amostras do grupo teste tiveram suas respectivas restaurações removidas, a profundidade medida e a dentina remanescente avaliada por um operador calibrado, seguindo critérios descritivos, quanto à consistência e a coloração. Nos dentes do grupo controle positivo, foram realizados preparos cavitários oclusais em até 4 mm de profundidade, enquanto que, no grupo controle negativo, o mesmo operador do estudo clínico realizou a remoção parcial de tecido cariado in vitro. A partir daí, todos os dentes foram preparados para análise de microdureza, que foi realizada por um examinador calibrado, que empregou o princípio de cegamento. Na análise da consistência, todos os dentes do grupo teste (n=13) apresentaram-se endurecidos, enquanto que 9, apresentaram coloração amarela-clara (8 do CIVRM e 1 do HC) e 4, castanho-escura (1 do CIVRM e 3 do HC). Para o teste de microdureza no grupo teste, obteve-se uma média KHN de 40,81 (±16,28) MPa, enquanto que nos grupos controles positivo e negativo, foram alcançados valores médios de 62,73 (±11,24) MPa e 19,15 (±6,99) MPa, respectivamente. A análise estatística mediante o teste ANOVA indicou que houve diferença significativa entre os 3 grupos. Foi constatada a remineralização da dentina de dentes decíduos em que foi realizada a técnica do capeamento pulpar indireto após um período médio de 3 anos e 8 meses, através de critérios clínico (consistência) e laboratorial (análise da microdureza).
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This work is divided in two parts. In the first part we develop the theory of discrete nonautonomous dynamical systems. In particular, we investigate skew-product dynamical system, periodicity, stability, center manifold, and bifurcation. In the second part we present some concrete models that are used in ecology/biology and economics. In addition to developing the mathematical theory of these models, we use simulations to construct graphs that illustrate and describe the dynamics of the models. One of the main contributions of this dissertation is the study of the stability of some concrete nonlinear maps using the center manifold theory. Moreover, the second contribution is the study of bifurcation, and in particular the construction of bifurcation diagrams in the parameter space of the autonomous Ricker competition model. Since the dynamics of the Ricker competition model is similar to the logistic competition model, we believe that there exists a certain class of two-dimensional maps with which we can generalize our results. Finally, using the Brouwer’s fixed point theorem and the construction of a compact invariant and convex subset of the space, we present a proof of the existence of a positive periodic solution of the nonautonomous Ricker competition model.
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Computer vision is a field that uses techniques to acquire, process, analyze and understand images from the real world in order to produce numeric or symbolic information in the form of decisions [1]. This project aims to use computer vision to prepare an app to analyze a Madeira Wine and characterize it (identify its variety) by its color. Dry or sweet wines, young or old wines have a specific color. It uses techniques to compare histograms in order to analyze the images taken from a test sample inside a special container designed for this purpose. The color analysis from a wine sample using an image captured by a smartphone can be difficult. Many factors affect the captured image such as, light conditions, the background of the sample container due to the many positions the photo can be taken (different to capture facing a white wall or facing the floor for example). Using new technologies such as 3D printing it was possible to create a prototype that aims to control the effect of those external factors on the captured image. The results for this experiment are good indicators for future works. Although it’s necessary to do more tests, the first tests had a success rate of 80% to 90% of correct results. This report documents the development of this project and all the techniques and steps required to execute the tests.
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AIRES, Kelson R. T.; SANTANA, André M.; MEDEIROS, Adelardo A. D. Optical flow using color information: preliminary results. In: ANNUAL ACM SYMPOSIUM ON APPLIED COMPUTING, 23., 2008, Fortaleza. Proceedings... Fortaleza: SAC, 2008.
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Composite resins have been subjected to structural modifications aiming at improved optical and mechanical properties. The present study consisted in an in vitro evaluation of the staining behavior of two nanohybrid resins (NH1 and NH2), a nanoparticulated resin (NP) and a microhybrid resin (MH). Samples of these materials were prepared and immersed in commonly ingested drinks, i.e., coffee, red wine and acai berry for periods of time varying from 1 to 60 days. Cylindrical samples of each resin were shaped using a metallic die and polymerized during 30 s both on the bottom and top of its disk. All samples were polished and immersed in the staining solutions. After 24 hours, three samples of each resin immersed in each solution were removed and placed in a spectrofotome ter for analysis. To that end, the samples were previously diluted in HCl at 50%. Tukey tests were carried out in the statistical analysis of the results. The results revealed that there was a clear difference in the staining behavior of each material. The nanoparticulated resin did not show better color stability compared to the microhybrid resin. Moreover, all resins stained with time. The degree of staining decreased in the sequence nanoparticulated, microhybrid, nanohybrid MH2 and MH1. Wine was the most aggressive drink followed by coffee and acai berry. SEM and image analysis revealed significant porosity on the surface of MH resin and relatively large pores on a NP sample. The NH2 resin was characterized by homogeneous dispersion of particles and limited porosity. Finally, the NH1 resin depicted the lowest porosity level. The results revealed that staining is likely related to the concentration of inorganic pa rticles and surface porosity
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The aim of the present study was to assess the effectiveness and adverse effects on dental enamel caused by nightguard vital bleaching with 10% carbamide peroxide. This was accomplished through the interaction of researchers from different areas such as dentistry, materials engineering and physics. Fifty volunteers took part in the doubleblind randomized controlled clinical trial. They were allocated to an experimental group that used Opalescence PF 10% (OPA) and a control group that used a placebo gel (PLA). Fragments of human dental enamel from the vestibular surface of healthy premolars, extracted for orthodontic reasons, were fixed to the vestibular surface of the first upper molars of the volunteers for in situ observation. Bleaching was performed at night for 21 days. The observation periods included Baseline (BL), T0 (21 days), T30 (30 days after treatment) and T180 (180 days after treatment, only for the OPA group). Tooth color was assessed by comparing it with the Vita® scale and by the degree of satisfaction expressed by the volunteer. We also assessed adverse clinical effects, dental sensitivity and gingival bleeding. The study of adverse effects on enamel was conducted in vivo and in situ, using the DIAGNOdent® laser fluorescence device to detect mineral loss. Scanning electron microscopy (SEM) was used to check for superficial morphological alterations, energy dispersive spectrophotometry (EDS) to semiquantitatively assess chemical composition using the Ca/P ratio, and the x-ray diffraction (XRD) technique to observe alterations in enamel microstructure. The results showed that nightguard vital bleaching with 10% carbamide peroxide was effective in 96% of the cases, versus 8% for the PLA group. Dental sensitivity was present in 36% (9/25) of the cases. There was no significant association between gingival bleeding and the type of gel used (p = 1.00). In vivo laser fluorescence analysis showed no difference in values for the control group, whereas in the OPA group there was a statistically significant difference between baseline values in relation to the subsequent periods (p<0.01), with lower mean values for post-bleaching times. There was a significant difference between the groups for times T0 and T30. Micrographic analysis showed no enamel surface alterations related to the treatment performed. No significant alteration in Ca/P ratio was observed in the OPA group (p = 0.624) or in the PLA group (p = 0.462) for each of the observation periods, nor between the groups studied (p=0.102). The XRD pattern for both groups showed the presence of three-phase Hydroxyapatite according to JCPDS files (9-0432[Ca5(PO4)3(OH)], 18-0303[Ca3(PO4)2.xH2O] and 25-0166[Ca5(PO4)3(OH, Cl, F)]). No other peak associated to other phases was found, independent of the group analyzed, which reveals there was no disappearance, nucleation or phase transformation. Neither was there any alteration in peak pattern location. With the methodology and protocol used in this study, nightguard vital bleaching with 10% carbamide peroxide proved to be an effective and safe procedure for dental enamel
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The objective of the present work was evaluate two techniques of smoking, the hot traditional and with use of smoke natural aroma or "liquid smoke", having as control Perna perna mussels vapor cooked. Sensorial characteristics were appraised (appearance, color, aroma, texture, flavor and salt tenor) and yield processing. The experimental design was completely randomized with three treatments (T1 = smoked with liquid smoke; T2 = traditional smoked and T3 = just cooked, control), with nine repetitions. For sensorial analysis 30 people were used, where each one was considered a block. There was significant difference for processing performance among treatments (P<0.05), however there was not significant difference independent of smoked technique applied. Nevertheless, smoking technique using smoke natural aroma was more attractive, presenting better results with relationship to sensorial characteristics and final product packaged for commercialization.
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Foi avaliado o efeito do processo de defumação a quente (45-90ºC/5 horas) e a frio (27-45ºC/10 horas) nas propriedades organolépticas, no rendimento e na composição dos filés de matrinxã (Brycon cephalus). Não houve diferença significativa no rendimento de filés defumados e não-defumados. As perdas no processo de defumação foram significativamente maiores para defumação a quente (19,37%) em comparação à defumação a frio (17,08%). O processo de defumação reduziu a umidade (in natura = 72,91%; defumado a quente = 58,51%; e defumado a frio = 59,68%) e aumentou os teores de proteína bruta, lipídios e cinzas. Houve diferença significativa somente nos teores de proteína no defumado a quente (28,07%) e defumado a frio (27,14%). O processo a frio resultou em melhor aparência e cor de filé, enquanto o processo a quente melhorou o sabor, o teor de sal e a aparência geral. O aroma e a textura não diferiram significativamente entre os processos. O processo de defumação a quente melhora as propriedades organolépticas e os níveis de proteína do filé de matrinxã.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This work proposes a kinematic control scheme, using visual feedback for a robot arm with five degrees of freedom. Using computational vision techniques, a method was developed to determine the cartesian 3d position and orientation of the robot arm (pose) using a robot image obtained through a camera. A colored triangular label is disposed on the robot manipulator tool and efficient heuristic rules are used to obtain the vertexes of that label in the image. The tool pose is obtained from those vertexes through numerical methods. A color calibration scheme based in the K-means algorithm was implemented to guarantee the robustness of the vision system in the presence of light variations. The extrinsic camera parameters are computed from the image of four coplanar points whose cartesian 3d coordinates, related to a fixed frame, are known. Two distinct poses of the tool, initial and final, obtained from image, are interpolated to generate a desired trajectory in cartesian space. The error signal in the proposed control scheme consists in the difference between the desired tool pose and the actual tool pose. Gains are applied at the error signal and the signal resulting is mapped in joint incrementals using the pseudoinverse of the manipulator jacobian matrix. These incrementals are applied to the manipulator joints moving the tool to the desired pose