467 resultados para conformação


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Radiotherapy is a branch of medical physics related to the treatment of malignant neoplasm, being an important instrument in the fight against cancer, when combined with the effort of a multidisciplinary team, composed of, physicians, physicists, nurses and technicians. Every year more than 3.5 million new cases of cancer are recorded in the world, being the prostate cancer responsible for approximately 25% of this amount (INCA and IARC, 2008). In this type of cancer, radiotherapy is a method indicated for treatement. The technological advance in this area over years has allowed a greater accuracy in the tumor location, more conformation of the radiation beam around the tumor, reducing the dose in healthy tissues and a consequent dose increase on treatment (Bedford et al., 1999). A radiotherapy planning, in which the physicist develops an important role, is composed of several steps, including choosing the best configuration of treatment beams. This choice has a close relationship with success of therapy and is critical to achieve the best distribution of dose inside the tumor and expose the least as possible the healthy tissue to radiation. In this work, two options for setting up camps in the first phase in a treatment of prostate cancer were simulated in computer planning: 4 fields orthogonal or “Box” with gantry angles in 00, 1800, 2700 e 90° and 4 fields angled or “X” (1350, 450, 3150 e 2250). The percentage of the rectal volume exposed to 40, 50, 60, 72 and 76 Gy should be limited to 60, 50, 25, 15 and 5% respectively (Greco et al., 2003). The femoral toxicity have limited dose by 70% of the total dose prescribed in a prostate treatment (Bedford et al., 1999). The planning of 27 patients with prostate adenocarcinoma submitted to 3D conformal radiotherapy were accompanied. As a result, it was assessed that the best TCP (tumor control probability)... (Complete abstract click electronic access below)

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The mechanical forming processes are the main means of transformation. Among all processes, the most used is rolling and broken down into flat and non-flat products. In the flat products are classified plates, and products no plans bars and profiles. Thus laminating products, mostly, are the raw materials for other processes of transformation, as stamping, forging, machining, bending and more. This work has focused on non-flat products, classified as bars and rods, watching a key point in the proceedings that is the product quality. Here is demonstrated through metallographic analysis of steel bars, hot-rolled, the characteristics of surface cracks in these bars

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As enzimas estão presentes em todas as células vivas, onde exercem a função de catalisadores das reações que compõem as vias catabólicas e anabólicas do metabolismo celular. Esses biocatalisadores são moléculas de proteínas e seu poder catalítico está associado à conformação nativa, que depende de condições específicas de pH, temperatura e força iônica do meio. Os micro-organismos são bastante atrativos para a indústria, pois possibilitam a produção de enzimas por processos fermentativos em larga escala com regularidade necessária e simplicidade na requisição nutricional. Assim, embora alguns biocatalisadores sejam extraídos de tecidos animais e vegetais, as enzimas industriais são, em sua maior parte, obtidas a partir de micro-organismos. Este trabalho teve como objetivo a produção das enzimas lipase e β-glucanase a partir dos fungos Aspergillus niger e Trichoderma reesei, respectivamente, em diferentes meios de cultura, para determinar as condições de maior produção da enzima em questão. As enzimas produzidas em agitador orbital foram obtidas a partir da filtração do produto da fermentação, precipitação com sulfato de amônio e liofilização. Após a produção e precipitação a atividade das enzimas e a concentração de proteínas foram quantificadas, os parâmetros cinéticos foram determinados frente a diferentes pHs, temperaturas e força iônica do meio. A lipase apresentou melhor atividade a 30°C e em pH 6,0. A presença dos íons Mg2+ e Zn2+ levaram a um aumento na atividade da enzima. A β-glucanase apresentou maiores atividades quando submetidas a 37°C e pH 5,0. Os íons Mg2+, Cu2+ e Ca2+ induziram melhor a atividade enzimática.

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The plastic deformation is widely used in the metallurgical market due to its positive factors such as low prices and high speed production. Forming process products are obtained in high quality, both surface quality and mechanical properties. Friction is an importante factor in metal forming. Friction study in metal forming can be accomplished indirectly, such as the ring test of friction. Two samples of different materials being mild steel and copper alloy were used. The results showed the influence of friction in the flow behavior of the deformation of the second phase, as evidenced by standard metallography. It is observed that in the outer regions of the ring, plastic deformation occured in the radial direction. In the central region of the disc deformation occured in the direction of compression and the inner region of the ring flux lines showed a significant deformation in the radial direction towards the center of the ring

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The society continues demonstrating its need regarding the products and services, even though it becomes increasingly value the protection of the environment. In this context, environmental management is defined as a management method that emphasizes to continuously improve results and promote sustainable development. Moreover it has as a tool the laws which provide the benchmarks and mechanisms for companies to adapt their activities in such a way that does not alter the quality of the environment. In this sense, in order to propose improvements to a dairy aiming their environmental suitability, a present study was prepared by following the production activities of the enterprise, the raising of standards and applicable legal requirements and environmental assessment for the preparation of an array of aspects and impacts with the task of identifying the most significant according to MOREIRA (2006). The results indicated that some of the impacts of high relevance are related to the generation of wastewater and solid waste, which do not have treatment and / or proper disposal and indeed require intervention for their suitability. Through, these results were drawn up proposals for actions conformation. In addition, they were proposed meeting the requirement for health and safety at work, in accordance with the standard regulations. This study has the function, therefore, propose to the company in question, an environmental management plan that ensures the protection of the environment and health of employees and consequently the improvement of production processes and products

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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

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Among the sexual hormones the estrogens are receiving major attention due to their biological activity. Such biological response is atributed to the best conformation recognized by their receptors, resulting in maximum responses. The estrogens are also considered responsible for most of disruptor´s effects caused by their presence in aquatic ecosystems. The 17β-estradiol hormone is produced by vertebrates during the reproductive phase of their lives and its presence has been detected in superficial waters. The objective of this study was to evaluate the cause-effect of tilapia exposition to the hormone 17β-estradiol through the analysis of biotransformation enzymes in liver and gills, complemented with the quantification of 17β-estradiol and estrone in water samples collected from fish ponds integrated to swine production. The present study was conducted under laboratory conditions, in a randomized experimental design with three levels of 17β-estradiol (E2) (0, 5, 15 µg L-1), with three replicates. After 7 days of exposure time, liver and gills were extracted to analyze three isoforms of cytochrome P450: EROD, BROD, PROD and the activity of Glutathione S-Transferase (GST). The results showed that the EROD activity (CYP1A), normally induced by the metabolism of aromatic compounds, did not present statistical differences among the treatments exposed to E2, what means that the hormone did not induce isoform 1A in fish under these particular experimental conditions. PROD activity was significantly altered in both concentrations, by means of 5 and 15 µg L-1, when compared to control. This result can indicate an important role of PROD on the metabolism of E2 present in water. Regarding to the BROD activity, it could be observed differences statistically significant between control and both groups of treatments. Two or more CYP isoforms can contribute to the metabolism of the same compound, what makes BROD a candidate as a next bioindicator of the exposure to E2 in aquatic ecosystems. Analysis of variance could confirm the effect of E2 statistically significant on the GST activity in liver tissues with >90% of significance (Prob>F = 0.0753). Furthermore, it was possible to observe that the values of GSTs activities in liver and gills in both, control and treatments, follow a tendency, that means, enzymatic activity in gills increase as the increasing of the activity in the liver tissues. In this study, the 17β–estradiol was found in measurable concentrations in three sampled points, and these values were similar to the findings of other authors at different locations in Brazil. In addition, those values are much higher than the minimum concentration that presented observable effects (10 ng L-1).

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Several alloys present the shape memory effect and among them, the equiatomic NiTi alloy, nitinol, is the most important one. It is usually used in several engineering applications and also in biomedical devices, in the fabrication of orthodontic wire, stents and Judet staples. Although a considerable amount of these biomedical devices is utilized in Brazil and a fraction of it is already made here, all nitinol used is bought abroad. Thus, it is important to develop the necessary know-how to fabricate NiTi wire and sheet. It would mean less importation with job creation and wealth generation for the country. In this work nitinol was obtained powder metallurgy from elemental powders of Ti and Ni using uniaxial compression and uniaxial compression followed by isostatic compression. The final densities achieved were determined by the Archimedes method. The precipitation of intermetallic secondary phases was studied and the samples were characterized by metallographic analysis, optical microscopy and X-ray diffraction. Results indicated that 50 hours sintering route showed a low amount of intermetallics, and no trace of unreacted powder. XRD and metallography at room temperature indicated B19’ as the predominant phase, which corresponds to martensite. Although density results showed little dispersion, the most dense sample was compacted under uniaxial compression and presented 4.8 g/cm3, corresponding to 20.84% porosity. Density variation was considered normal to the measurement process and independent of the compaction mode

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

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This academic report presents results of the research developed between 2012 and 2015, and it had as main goal the development of new mapping possibilities of the central areas of the cities of Marília/SP, São Carlos/SP and São José do Rio Preto/SP. We developed this research using mostly the database from Cadastro Nacional de Endereços Para Fins Estatísticos (CNEFE), and after processing the information, it was added the typology established in the Cadastro Nacional de Atividades Econômicas (CNAE). This database, after the final treatment process, provided us information that made possible the production of thematic maps which are used to study central areas, allowing the analysis of spatial logics of companies, the identification of concentration and dispersion of economic activities, arrangement of specialized axis, expansion of the central area, reorganization of the city, among other process and phenomena

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This work approaches the main methods of plastic deformation of metals, with a focus on the deep drawing process. The mechanical properties were evaluated with the tension tests. It is presented the aluminum alloys designation, followed by applying heat treatments and the designation of tempers. The manufacture of aluminum beverage cans is described step by step, in general terms. The main objective is to analyze how different cans background geometries have great influence on the dome reversal. To be able to achieve the goal it was necessary to use cans of different manufacturers, which were used in buckle tests to obtain the reversal pressures, tensile tests and geometric analysis. Finally empirical equations were obtained correlating these variables, and it was observed that the conformation of reforming change significantly it's behavior

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Pressure vessels are equipments that require a great care because of their high cost and human life risk in case of fail, and its fabrication methods are different for each manufacturer. Normally, pressure vessels and its parts are fabricated by welding, which may change local properties of metals. The head of a pressure vessel is a very important structural component and it is fabricated by welding and mechanical conformation. Because its excellent mechanical properties, de steel A-516 Grade 70 is often used in manufacturing of large pressure vessels that are subjected to high pressure and temperature, but was verified that its mechanical resistance is decreased when submitted to a tension relief heat treatment. By experience it was defined that before mechanical conformation of the head of a large pressure vessel, the steel should be submitted to a stress relief heat treatment in order to facilitate the mechanical conformation, but there is no quantitative analysis to prove this method and study its possible risks. In the present work the steel A-516 Grade 70 demonstrated a decrease of its mechanical resistance when submitted to a stress relief heat treatment, but keeping above the minimum limit defined in the literature. By other side its ductility was substantially increased, being possible to deduce that the stress relief heat treatment before mechanical conformation is a viable e recommended technique, but with reservations. With the data acquired during the fabrication e preparation of the specimen and the result of the tests, it was possible to elaborate a welding procedure that provides the same results obtained in this present work

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