Extração de vias combinando métodos de detecção de regiões e linhas em imagens de intensidade de pulso laser

This paper aims at extracting street centerlines from previously isolated street regions by using the image of laser scanning intensity. In this image, streets are easily identified, since they manifest as dark, elongate ribbons contrasting with background objects. The intensity image is segmented by using the region growing technique, which generates regions representing the streets. From these regions, the street centerlines are extracted in two manners. The first one is through the Steger lines detection method combined with a line length thresholding by which lines being shorter than a minimum length are removed. The other manner is by combining the skeletonization method of regions based on the Medial Axis Transform and with a pruning process to eliminate as much as possible the ramifications. Experiments showed that the Steger-based method provided results better than the method based on skeletonization.

Photodynamic inactivation of biofilm: Taking a lightly colored approach to stubborn infection

Microbial biofilms are responsible for a variety of microbial infections in different parts of the body, such as urinary tract infections, catheter infections, middle-ear infections, gingivitis, caries, periodontitis, orthopedic implants, and so on. The microbial biofilm cells have properties and gene expression patterns distinct from planktonic cells, including phenotypic variations in enzymic activity, cell wall composition and surface structure, which increase the resistance to antibiotics and other antimicrobial treatments. There is consequently an urgent need for new approaches to attack biofilm-associated microorganisms, and antimicrobial photodynamic therapy (aPDT) may be a promising candidate. aPDT involves the combination of a nontoxic dye and low-intensity visible light which, in the presence of oxygen, produces cytotoxic reactive oxygen species. It has been demonstrated that many biofilms are susceptible to aPDT, particularly in dental disease. This review will focus on aspects of aPDT that are designed to increase efficiency against biofilms modalities to enhance penetration of photosensitizer into biofilm, and a combination of aPDT with biofilm-disrupting agents. © 2013 Informa UK Ltd.

Recent mouse and rat methods for the study of experimental oral candidiasis

The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. © 2013 Landes Bioscience.

Photogrammetric refinement of laser-based building roof contours

In this paper a photogrammetric method is proposed for refining 3D building roof contours extracted from airborne laser scanning data. It is assumed that laser-derived planar faces of roofs are potentially accurate, while laser-derived building roof contours are not well defined. First, polygons representing building roof contours are extracted from a high-resolution aerial image. In the sequence, straight-line segments delimitating each building roof polygon are projected onto the corresponding laser-derived roof planes by using a new line-based photogrammetric model. Finally, refined 3D building roof contours are reconstructed by connecting every pair of photogrammetrically- projected adjacent straight lines. The obtained results showed that the proposed approach worked properly, meaning that the integration of image data and laser scanning data allows better results to be obtained, when compared to the results generated by using only laser scanning data. © 2013 IEEE.

Efeito do sistema de acabamento e polimento na rugosidade superficial e formação in situ de biofilme dentário inicial em cerâmica feldspática micro-particulada

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detecção de regiões de via integrando dados de varredura a LASER aerotransportado e imagens de alta resolução

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reconstrução de contornos e cumeeiras de telhados de edifícios a partir de imagens aéreas de alta-resolução e poliedros representativos de edifícios extraídos de dados LASER

Pós-graduação em Ciências Cartográficas - FCT

Estudo do desempenho de filmes de Ti02 como aceptor de elétrons e obtenção de fases puras de nanopartículas de Ti02: anatase e rutila, sintetizado por uma nova rota química

Pós-graduação em Ciência dos Materiais - FEIS

Refinamento geométrico de contornos e cumeeiras de telhados de edifícios extraídos de dados laser com uso de imagem aérea

In this paper, a method is proposed to refine the LASER 3D roofs geometrically by using a high-resolution aerial image and Markov Random Field (MRF) models. In order to do so, a MRF description for grouping straight lines is developed, assuming that each projected side contour and ridge is topologically correct and that it is only necessary to improve its accuracy. Although the combination of laser data with data from image is most justified for refining roof contour, the structure of ridges can give greater robustness in the topological description of the roof structure. The MRF model is formulated based on relationships (length, proximity, and orientation) between the straight lines extracted from the image and projected polygon and also on retangularity and corner injunctions. The energy function associated with MRF is minimized by the genetic algorithm optimization method, resulting in the grouping of straight lines for each roof object. Finally, each grouping of straight lines is topologically reconstructed based on the topology of the corresponding LASER scanning polygon projected onto the image-space. The results obtained were satisfactory. This method was able to provide polygons roof refined buildings in which most of its contour sides and ridges were geometrically improved.

Monitoramento e avaliação de processos erosivos marginais em reservatórios de usinas hidrelétricas por meio de varredura a laser

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito na adesão de pinos de fibra de vidro na dentina radicular após irrigação com diferentes formulações de ácido peracético e cimentação com RelyX U200

Pós-graduação em Odontologia - FOAR

Montagem e avaliação de um sistema de varredura a LASER embarcado em VANT

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Montagem e avaliação de um sistema de varredura a LASER embarcado em VANT

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microtensile bond strength of resin composite to dentin treated with Er:YAG laser of bleached teeth

The objective of this study was to evaluate the influence of Er:YAG laser (lambda = 2.94 mu m) on microtensile bond strength (mu TBS) and superficial morphology of bovine dentin bleached with 16% carbamide peroxide. Forty bovine teeth blocks (7 x 3 x 3 mm(3)) were randomly assigned to four groups: G1- bleaching and Er:YAG irradiation with energy density of 25.56 J/cm(2) (focused mode); G2 - bleaching; G3 - no-bleaching and Er:YAG irradiation (25.56 J/cm(2)); G4 - control, non-treated. G1 and G2 were bleached with 16% carbamide peroxide for 6 h during 21 days. Afterwards, all blocks were abraded with 320 to 600-grit abrasive papers to obtain flat standardized dentin surfaces. G1 and G3 were Er:YAG irradiated. Blocks were immediately restored with 4-mm-high composite resin (Adper Single Bond 2, Z-250-3 M/ESPE). After 24 h, the restored blocks (n = 9) were serially sectioned and trimmed to an hour-glass shape of approximately 1 mm(2) at the bonded interface area, and tested in tension in a universal testing machine (1 mm/ min). Failure mode was determined at a magnification of 100x using a stereomicroscope. One block of each group was selected for scanning electron microscope (SEM) analysis. mu TBS data was analyzed by two-way ANOVA and Tukey test (alpha = 0.05). Mean bond strengths (SD) in MPa were: G1- 32.7 (5.9)(A); G2- 31.1 (6.3)(A); G3- 25.2 (8.3)(B); G4- 36.7 (9.9).(A) Groups with different uppercase letters were significantly different from each other (p < .05). Enamel bleaching procedure did not affect mu TBS values for dentin adhesion. Er:YAG laser irradiation with 25.56 J/cm(2) prior to adhesive procedure of bleached teeth did not affect mu TBS at dentin and promoted a dentin surface with no smear layer and opened dentin tubules observed under SEM. On the other hand, Er:YAG laser irradiation prior to adhesive procedure of non-bleached surface impaired mu TBS compared to the control group.

Influence of low-level laser associated with osteogenic proteins recombinant human BMP-2 and Hevea brasiliensis on bone repair in Wistar rats

This study analyzed the newly formed bone tissue after application of recombinant human BMP-2 (rhBMP-2) and P-1 (extracted from Hevea brasiliensis) proteins, 2 weeks after the creation of a critical bone defect in male Wistar rats treated or not with a low-intensity laser (GaAlAs 780 nm, 60 mW of power, and energy density dose of 30 J/cm2). The animals were divided into two major groups: (1) bone defect plus low-intensity laser treatment and (2) bone defect without laser irradiation. The following subgroups were also analyzed: (a) 5 mu g of pure rhBMP-2; (b) 5 mu g of pure P-1 fraction; (c) 5 mu g of rhBMP-2/monoolein gel; (d) 5 mu g of P-1 fraction/monoolein gel; (e) pure monoolein gel. Comparisons of the groups receiving laser treatment with those that did not receive laser irradiation show differences in the areas of new bone tissue. The group treated with 5 mu g of rhBMP-2 and laser irradiation was not significantly different (P >0.05) than the nonirradiated group that received the same treatment. The irradiated, rhBMP-2/monoolein gel treatment group showed a lower area of bone formation than the nonirradiated, rhBMP-2/gel monoolein treatment group (P < 0.001). The area of new bone tissue in the other nonirradiated and irradiated groups was not significantly different (P > 0.05). Furthermore, the group that received the 5 mu g of rhBMP-2 application showed the greatest bone formation. We conclude that the laser treatment did not interfere with the area of new bone tissue growth and that the greatest stimulus for bone formation involved application of the rhBMP-2 protein. Microsc. Res. Tech. 2011. (c) 2011 Wiley Periodicals, Inc.