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Search Results: 1 - 10 of 32406 matches for " Roberto Heleno Lopes "
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Síndrome de Boerhaave: relato de caso Boerhaave′s syndrome: case report
Oswaldo Passos Filho,Heron Crusoé Cangussu,Roberto Heleno Lopes,Antonio Talvane Torres de Oliveira
Revista do Colégio Brasileiro de Cirurgi?es , 2013,
Abstract: Spontaneous esophageal rupture carries high morbidity and mortality. The main prognostic factor is early diagnosis, before 12 hours, and appropriate treatment. This is a case report of a 41-years-old man with late esophageal rupture diagnosis treated successfully with transmediatinal esophagectomy and esophageal-gastric tube cervical anastomosis.
A produ o bibliográfica em coautoria na área de educa o
ALICE CASIMIRO LOPES,HUGO HELENO CAMILO COSTA
Revista Brasileira de Educa??o , 2012,
Abstract:
Effects of isothermal treatment on microstructure and scratch test behavior of plasma sprayed zirconia coatings
Veloso, Guilherme;Alves, Heleno Rocha;Branco, José Roberto Tavares;
Materials Research , 2004, DOI: 10.1590/S1516-14392004000100026
Abstract: the increase of the petroleum cost in the last decades revitalized the interest for lighter and more economic vehicles. simultaneously, the demand for safe and unpolluted transports grows. the application of thermal barriers coatings (tbc) on combustion chamber and on flat surface of pistons reduces the thermal losses of the engines, resulting in higher temperatures in the combustion chamber. this fact contributes to the improvement of the thermal efficiency (performance) and for the reduction of incomplete combustion. supported on these initial ideas, thermal barriers coatings constituted by cao partially stabilized zirconia were produced and their microstructure examined. this coating still presents some drawbacks associated with thermal stresses and permeability to oxidizing gases, which will, eventually, lead to failure of the tbc by spallation. the failure may, in general, be associated to one of three factors: oxide growth at the ceramic-metal interface, formed during thermal cycling; stress build-up due to thermal cycling; and metal-oxide interface segregation, mainly of s. however, it is also relevant to understand the behavior of tbc's under isothermal oxidation. therefore, this paper investigates the effect of oxidation on the adherence of thermal sprayed coatings. the adherence was measured by linear scratching tests, widely used for thin coatings. plasma sprayed calcia partially stabilized zirconia was used as tbc and ni-5%al as bond coat, with al substrates. coated samples were submitted to heat treatments at 500 °c, for 50 h. the microstructures were examined by optical light microscopy, x-ray diffraction, profilometry and sem.
Effects of isothermal treatment on microstructure and scratch test behavior of plasma sprayed zirconia coatings
Veloso Guilherme,Alves Heleno Rocha,Branco José Roberto Tavares
Materials Research , 2004,
Abstract: The increase of the petroleum cost in the last decades revitalized the interest for lighter and more economic vehicles. Simultaneously, the demand for safe and unpolluted transports grows. The application of thermal barriers coatings (TBC) on combustion chamber and on flat surface of pistons reduces the thermal losses of the engines, resulting in higher temperatures in the combustion chamber. This fact contributes to the improvement of the thermal efficiency (performance) and for the reduction of incomplete combustion. Supported on these initial ideas, thermal barriers coatings constituted by CaO partially stabilized zirconia were produced and their microstructure examined. This coating still presents some drawbacks associated with thermal stresses and permeability to oxidizing gases, which will, eventually, lead to failure of the TBC by spallation. The failure may, in general, be associated to one of three factors: oxide growth at the ceramic-metal interface, formed during thermal cycling; stress build-up due to thermal cycling; and metal-oxide interface segregation, mainly of S. However, it is also relevant to understand the behavior of TBC's under isothermal oxidation. Therefore, this paper investigates the effect of oxidation on the adherence of thermal sprayed coatings. The adherence was measured by linear scratching tests, widely used for thin coatings. Plasma sprayed calcia partially stabilized zirconia was used as TBC and Ni-5%Al as bond coat, with Al substrates. Coated samples were submitted to heat treatments at 500 °C, for 50 h. The microstructures were examined by optical light microscopy, X-ray diffraction, profilometry and SEM.
Influence of CDW Recycled Aggregate on Drying Shrinkage of Mortar  [PDF]
Paulo Roberto Lopes Lima, Monica Batista Leite
Open Journal of Civil Engineering (OJCE) , 2012, DOI: 10.4236/ojce.2012.22009
Abstract: The use of fine recycled aggregates as raw material in the production of mortars appears as a good alternative to minimize waste disposal, so as to reduce natural resources consumption and to find and supply suitable substitutes for natural aggregates. However, the use of this alternative material in a safe way must be carried out by a wide investigation of its long term behavior. In this way, this paper will examine the mechanical strength, physical properties and drying shrinkage of mortar, which use recycled fine aggregates that have originated from construction and demolition waste (CDW) containing mortar (55%), ceramic (26%) and concrete (16%). Two natural mortars, made with natural sand, were produced with cement/sand ratios of 1:4 and 1:8 (by weight) and a fixed consistency index of 260 +10 mm. Recycled mortar was produced with 50% of substitution rate, in volume, of natural aggregate by recycled one. Results show that recycled mortars present higher total porosity, absorption rate and drying shrinkage than reference mortar.
Solu??o de problemas de planejamento florestal com restri??es de inteireza utilizando busca tabu
Rodrigues, Flávio Lopes;Leite, Helio Garcia;Santos, Heleno do Nascimentos;Souza, Agostinho Lopes de;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000500013
Abstract: this work aimed to develop and test an algorithm based on tabu search (ts) metaheuristics; to solve problems of forest management with integer constraints. ts was tested in five problems containing between 12 and 423 decision variables subjected to singularity constraints, minimum and maximum periodic productions. all the problems aimed at maximizing the net present value. ts was codified into delphi 5.0 language and the tests were performed in a microcomputer amd k6ii 500 mhz, ram memory 64 mb and hard disk 15gb. ts performance was evaluated according to efficacy and efficiency measures. the different values or categories for the ts parameters were tested and compared to their effects on algorithm efficacy. the best configuration of the parameters was selected by applying the l&o test at 1% probability and analyses via descriptive statistics. the best parameter configuration provided ts an average efficacy of 95.97%, a minimum value equal to 90.39%, a maximum value equal to 98.84%, with a variation coefficient of 2.48% of the mathematical optimum. for the most complex problem, ts efficiency of the exact algorithm branch and bound. thus, ts is a rrather attractive approach to solving important forest management problems.
Solu o de problemas de planejamento florestal com restri es de inteireza utilizando busca tabu
Rodrigues Flávio Lopes,Leite Helio Garcia,Santos Heleno do Nascimentos,Souza Agostinho Lopes de
Revista árvore , 2003,
Abstract: Este trabalho teve como objetivos desenvolver e testar um algoritmo com base na metaheurística busca tabu (BT), para a solu o de problemas de gerenciamento florestal com restri es de inteireza. Os problemas avaliados tinham entre 93 e 423 variáveis de decis o, sujeitos às restri es de singularidade, produ o mínima e produ o máxima periódicas. Todos os problemas tiveram como objetivo a maximiza o do valor presente líquido. O algoritmo para implementa o da BT foi codificado em ambiente delphi 5.0 e os testes foram efetuados em um microcomputador AMD K6II 500 MHZ, com memória RAM de 64 MB e disco rígido de 15GB. O desempenho da BT foi avaliado de acordo com as medidas de eficácia e eficiência. Os diferentes valores ou categorias dos parametros da BT foram testados e comparados quanto aos seus efeitos na eficácia do algoritmo. A sele o da melhor configura o de parametros foi feita com o teste L&O, a 1% de probabilidade, e as análises através de estatísticas descritivas. A melhor configura o de parametros propiciou à BT eficácia média de 95,97%, valor mínimo igual a 90,39% e valor máximo igual a 98,84%, com um coeficiente de varia o de 2,48% do ótimo matemático. Para o problema de maior porte, a eficiência da BT foi duas vezes superior à eficiência do algoritmo exato branch and bound, apresentando-se como uma abordagem muito atrativa para solu o de importantes problemas de gerenciamento florestal.
Compara??o de duas diferentes intensidades de alongamento na amplitude de movimento
Chagas, Mauro Heleno;Bhering, Elder Lopes;Bergamini, Juliana Castro;Menzel, Hans-Joachim;
Revista Brasileira de Medicina do Esporte , 2008, DOI: 10.1590/S1517-86922008000200003
Abstract: stretching is a usual practice in flexibility training; however, specific information on load is still scarce, mainly about what concerns the stretching intensity. the aim of the present study was to investigate the acute effect of two stretching intensities in the range of motion (rom) of knee extension, after a single training session. fourteen males participated in this study. both lower limbs of each volunteer were assessed, being one leg submitted to a submaximal stretching program (ssp) and the other to a maximal stretching program (msp). the training session consisted of four static-passive hamstring stretching repetition of fifteen seconds each. msp exhibited a significant difference between pre-test (68.0 ± 10.5) and post-test (74.0 ± 10.0) to the rom figures. however, significant difference was not found for the pre-test (68.8 ± 14.0) and post-test (70.9 ± 14.4) for the ssp. the results analyzed through two-way anova method showed significant interaction between the group and the test (f= 1.26; df= 8.62; p= 0.007). these findings demonstrated that the maximal stretching program causes an acute increase at rom. thus, the studies to assess the ideal training load components in order to improve flexibility should not take the stimulus intensity control for granted.
Catálogo dos Peixes Marinhos do Laboratório de Ictiologia da Universidade Federal do Rio de Janeiro. Parte I: Chondrichthyes (Rajiformes). Teleostei (Elopiformes a Dactylopteriformes)
Lopes, Paulo Roberto Duarte;
Revista Brasileira de Zoologia , 1989, DOI: 10.1590/S0101-81751989000200004
Abstract: the present paper is the first part of the catalogue of marine fishes belonging to the collection of the laboratory of ichthyology (universidade federal do rio de janeiro-rj) to be published. here are included chondrichthyes (rajiformes) and part of osteichthyes, teleostei (elopiformes to dactylopteriformes) in a total amount of 30 families, 52 genera and 62 species. the most part of the material have been collected at the littoral of the state of rio de janeiro. for each species considered is given the vulgar name (when known in southeastern brazil), the known distribution (in western atlantic ocean) and some data as collecting locality, total number of collected specimens and the register number in the collection. scorpaena isthmensis meek & hildebrand, 1928 (scorpaenidae) is for the first time mentioned for the southern littoral of brazil.
LOCALIZA O GEODéSICA DA LINHA DE PREAMAR MéDIA COM RELA O AO ANO DE 1831, NA PRAIA DO FUTURO/ FORTALEZA-CE, BRASIL - DOI 10.5216/bgg.v32i1.18954
Paulo Roberto Lopes Thiers
Boletim Goiano de Geografia , 2012,
Abstract: O presente trabalho tem por fim apresentar resultados, descri o de metodologia para a representa o cartográfica, em escala cadastral, da localiza o geodésica da Linha de Preamar Média (LPM) e Linha de Terrenos de Marinha (LTM), com referência ao ano de 1831, em área da Praia do Futuro, localizada na cidade de Fortaleza, Estado do Ceará. Para a realiza o do estudo, foram utilizados métodos que envolvem conceitos de geodésia, cartografia e técnicas de sensoriamento remoto. Ao longo de toda a linha da costa brasileira há situa es que descrevem a ocupa o da faixa de terrenos de marinha: terrenos pertencentes à Uni o. Os resultados da determina o da LPM possibilitam o posicionamento da LTM, que é a distancia horizontal de 33m, contados a partir da LPM. O estudo representa, graficamente, a ocupa o da faixa de terrenos de marinha da Praia do Futuro, por edifica es/barracas. Este trabalho, parte da perícia encomendada pela Justi a Federal no Estado do Ceará, conclui que, efetivamente, apenas parte de estruturas das barracas da Praia do Futuro ocupa terrenos da Uni o.
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