999 resultados para Poland. 1921 Mar. 18.
Resumo:
Os aços inoxidáveis supermartensÃticos (SMSS) são usados em ambientes agressivos devido à sua boa soldabilidade, boas propriedades mecânicas em temperaturas elevadas e superior resistência à corrosão sob tensão. Aplicações na exploração de petróleo demandam superior combinação de propriedades e os aços inoxidáveis duplex e superduplex têm sido aplicados nessa área, a despeito de seus custos elevados. Os SMSS consistem numa alternativa técnica e econômica ao uso daqueles aços. Nesse trabalho, adições de Nb e Ti foram realizadas com o intuito de minimizar o efeito de sensitização, promover o refino de grãos e foram estudados os aspectos microestruturais e a resistência à corrosão por pites em água do mar. A formação e a evolução dos pites foram acompanhadas por ensaios de corrosão, microscopia óptica e eletrônica, focalizando suas morfologias. O aço com Ti apresentou o melhor desempenho quanto à corrosão, com o maior potencial de corrosão e menor potencial de pite entre os aços em estudo. O aço com Nb, apesar de apresentar potencial de corrosão superior ao do aço sem adição, teve um potencial de pite inferior ao do mesmo.
Resumo:
The circulation and transport of suspended particulate matter in the Caravelas Estuary are assessed. Nearly-synoptic hourly hydrographic, current (ADCP velocity and volume transport) and suspended particulate matter data were collected during a full semidiurnal spring tide, on the two transects Boca do Tomba and Barra Velha and on longitudinal sections at low and high tide. On the first transect the peak ebb currents (-1.5 ms-1) were almost twice as strong as those of the wider and shallow Barra Velha inlet (-0.80 ms-1) and the peak flood currents were 0.75 and 0.60 ms-1, respectively. Due to the strong tidal currents both inlets had weak vertical salinity stratification and were classified with the Stratification-circulation Diagram as Type 2a (partially mixed-weakly stratified) and Type 1a (well mixed). Volume transports were very close, ranging from -3,500 to 3,100 m³s-1 at the ebb and flood, respectively, with a residual -630 m³s-1. The concentration of the suspended particulate matter was closely related to the tidal variation and decreased landwards from 50 mg.L-1 at the estuary mouth, to 10 mg.L-1 at distances of 9 and 16 km for the low and high tide experiments, respectively. The total residual SPM transport was out of the estuary at rates of -18 tons per tidal cycle.
Resumo:
O objetivo do presente estudo é caracterizar a hidrodinâmica e o transporte de material particulado em suspensão (MPS) no estuário de Caravelas sob diferentes condições de maré e vazão fluvial. Foram realizadas quatro campanhas hidrográficas durante ciclos completos de maré, sendo em condições de maré de sizÃgia e quadratura, e durante os perÃodos seco e chuvoso. Dados de nÃvel de água, velocidade e direção de correntes, salinidade, temperatura e turbidez foram obtidos em uma estação fixa próxima da desembocadura do estuário. A partir destes dados foram obtidos os transportes residuais de MPS e calculado os mecanismos de transporte. As maiores concentrações médias de material particulado em suspensão ocorreram em condições de sizÃgia. Em condições de maré de quadraturao transporte resultante de MPS foi com sentido estuário acima, porém de pequena intensidade. Em condições de sizÃgia o estuário é caracterizado por correntes mais intensas e assimétricas, com dominância de vazante. Durante a condição de sizÃgia o estuário pode atuar como importador ou exportador de MPS. O estuário do rio Caravelas foi classificado como bem misturado e fracamente estratificado. A hidrografia e o balanço sedimentar são principalmente modulados pela altura da marée o aporte de água doce é irrelevante.
Resumo:
Nyssomyia intermedia s. lat. tem sido citada por vários autores no Paraná. No entanto, alguns estudos apontam que esse táxon corresponde a Nyssomyia neivai (Pinto). Em coletas realizadas em galinheiro e em ambiente de mata, com armadilhas, entre novembro de 2005 e outubro de 2006, em Adrianópolis, Morretes e Pontal do Paraná, localizados na região de Mata Atlântica na Serra do Mar e no litoral do Paraná, sete fêmeas de Nyssomyia intermedia s. str. (Lutz & Neiva) foram encontradas juntamente com outras 14 espécies de flo ebotomÃneos, confirmando a ocorrência de N.intermedia em área de costa e de mata Atlântica do Paraná.
Resumo:
Every year, autochthonous cases of Plasmodium vivax malaria occur in low-endemicity areas of Vale do Ribeira in the south-eastern part of the Atlantic Forest, state of São Paulo, where Anopheles cruzii and Anopheles bellator are considered the primary vectors. However, other species in the subgenus Nyssorhynchus of Anopheles (e.g., Anopheles marajoara) are abundant and may participate in the dynamics of malarial transmission in that region. The objectives of the present study were to assess the spatial distribution of An. cruzii, An. bellator and An. marajoara and to associate the presence of these species with malaria cases in the municipalities of the Vale do Ribeira. Potential habitat suitability modelling was applied to determine both the spatial distribution of An. cruzii, An. bellator and An. marajoara and to establish the density of each species. Poisson regression was utilized to associate malaria cases with estimated vector densities. As a result, An. cruzii was correlated with the forested slopes of the Serra do Mar, An. bellator with the coastal plain and An. marajoara with the deforested areas. Moreover, both An. marajoara and An. cruzii were positively associated with malaria cases. Considering that An. marajoara was demonstrated to be a primary vector of human Plasmodium in the rural areas of the state of Amapá, more attention should be given to the species in the deforested areas of the Atlantic Forest, where it might be a secondary vector.
Resumo:
São apresentadas diferentes experiências e metodologias empregadas por registros informatizados de imunização (RII), no enfoque da saúde infantil. O levantamento bibliográfico abrangeu publicações de 1990 a 2006, existentes nas bases MEDLINE, SciELO, PubMed e EMBASE. Outros sÃtios eletrônicos de organizações nacionais e internacionais de saúde foram pesquisados. Em virtude da ausência de publicações sobre RII no Brasil, as fontes de informação foram a Coordenação Nacional e as Coordenações Estaduais do Programa Nacional de Imunizações, além do Departamento de Informática do Sistema Único de Saúde. Selecionaram-se apenas artigos que abordam RII em saúde infantil. Foram localizados 109 artigos publicados em 35 revistas especializadas. São apresentados aspectos históricos e conceituais, objetivos, funções, relevância e indicadores de desempenho e de custo-efetividade, além das próprias limitações dos RII, assim como experiências em paÃses selecionados, inclusive no Brasil. Os RII integrados a outros sistemas de informação vêm sendo aplicados como importante instrumento para a identificação de populações com menor acesso ou adesão aos programas de vacinação e em sistemas de vigilância ativa de eventos adversos pós-vacina
Resumo:
To identify natural infections by Leishmania spp. in insect vectors of cutaneous and visceral leishmaniasis, we performed field studies in natural and anthropic environments in the Guaicurus Settlement (Bodoquena Range) of the Bonito municipality, Mato Grosso do Sul state, Brazil. From October 2002 to October 2003, a total of 1395 sandfly females were captured with Shannon and light traps and dissected in search of flagellates. The sample is composed of a total of 13 species, with Lutzomyia almerioi (59.9%) and Lutzomyia longipalpis (31.4%) predominant. Infections by flagellates were directly observed in three of the dissected of Lu. almerioi females (0.36%). To increase the sensitivity of detection, DNA extracted from pools of the 1220 dissected females (Lu. almerioi 808, Lu. longipalpis 399 and Nyssomyia whitmani 13) was subjected to small subunit rRNA-based polymerase chain reactions (SSU-PCR). DNA from Leishmania (L.) infantum chagasi was detected in at least 0.37% of Lu. almerioi females and in 0.25% of Lu. longipalpis females. The DNA of the Leishmania (Viannia) sp. was detected in 0.12% of Lu. almerioi and in 0.70% of Lu. longipalpis. Leishmania (L.) amazonensis was found in 1.25% of Lu. longipalpis. Mixed infections of L. (Leishmania) sp. and L. (Viannia) sp. were found in 0.50% of Lu. longipalpis. When considering that each positive pool contained at least a single infected specimen, we found a 1.23% rate of Leishmania spp. infection among the total population of dissected female sand flies as determined by PCR. This is the first report of natural infection by L. (L.) infantum chagasi and L. (Viannia) sp. in Lu. almerioi. It is also the first report of infection by L. (Viannia) sp. in Lu. longipalpis. The observation that Lu. longipalpis and Lu. almerioi are naturally infected by agents of both cutaneous and visceral leishmaniases suggests that these two species play a role in the transmission (continua) (continuação) of these diseases within the study area. Furthermore, the finding that Lu. longipalpis has been naturally infected by L. (L.) amazonensis and L. (Viannia) sp., and Lu. almerioi by L. (L.) infantum chagasi and L. (Viannia), suggests their participation as permissive vectors
Resumo:
O estudo descreve as caracterÃsticas do padrão de atividade fÃsica da população adulta das capitais de Estados brasileiros e do Distrito Federal em 2006. Os dados foram coletados pelo sistema de vigilância de fatores de risco e proteção para doenças crônicas por inquérito telefônico (Vigitel) em uma amostra probabilÃstica da população com 18 ou mais anos de idade (n=54.369). Foram analisados dois indicadores: ativo no lazer; e sedentário. Os indivÃduos ativos no lazer foram 14,9%, a maioria homens. A caminhada é a modalidade mais comum, para ambos os sexos. A freqüência de ativos no lazer aumenta com a escolaridade e diminui com a idade. O sedentarismo já atingiu 29,2% da população adulta, com maior freqüência no sexo masculino, e aumenta com a idade e com a escolaridade. O perfil de atividade fÃsica é insatisfatório em todas as cidades, o que determina a necessidade de mais esforços no estÃmulo à prática da atividade fÃsica
Resumo:
A ação da Faculdade de Saúde Pública da Universidade de São Paulo na luta contra o tabagismo teve inÃcio em 1975, quando a instituição participou da III Conferência Mundial de Fumo e Saúde, realizada em New York (EUA). Depois de três décadas de trabalho ininterrupto, ela recebeu, em 2008, da Secretaria de Estado da Saúde de São Paulo, o selo prata de certificação de ambiente livre do tabaco. Nesse espaço de tempo, ao lado de um trabalho educativo, realizado corpo a corpo com docentes, funcionários e alunos, foram realizadas pesquisas, treinamentos e desenvolvido toda uma programação orientada pelo Ministério da Saúde / Instituto Nacional do Câncer. Foram também produzidas inúmeras monografias de mestrado, teses de doutorado e de livre docência, tendo como tema o tabagismo do ponto de vista educativo, social, médico e sanitário. Este artigo pretendeu fazer o relato dessa trajetória
Resumo:
Various methods are currently used in order to predict shallow landslides within the catchment scale. Among them, physically based models present advantages associated with the physical description of processes by means of mathematical equations. The main objective of this research is the prediction of shallow landslides using TRIGRS model, in a pilot catchment located at Serra do Mar mountain range, Sao Paulo State, southeastern Brazil. Susceptibility scenarios have been simulated taking into account different mechanical and hydrological values. These scenarios were analysed based on a landslide scars map from the January 1985 event, upon which two indexes were applied: Scars Concentration (SC - ratio between the number of cells with scars, in each class, and the total number of cells with scars within the catchment) and Landslide Potential (LP - ratio between the number of cells with scars, in each class, and the total number of cells in that same class). The results showed a significant agreement between the simulated scenarios and the scar's map. In unstable areas (SF <= 1), the SC values exceeded 50% in all scenarios. Based on the results, the use of this model should be considered an important tool for shallow landslide prediction, especially in areas where mechanical and hydrological properties of the materials are not well known.
Resumo:
The growing interest in solar twins is motivated by the possibility of comparing them directly to the Sun. To carry on this kind of analysis, we need to know their physical characteristics with precision. Our first objective is to use asteroseismology and interferometry on the brightest of them: 18 Sco. We observed the star during 12 nights with HARPS for seismology and used the PAVO beam-combiner at CHARA for interferometry. An average large frequency separation 134.4+/-0.3 mu Hz and angular and linear radiuses of 0.6759 +/- 0.0062 mas and 1.010 +/- 0.009 R(circle dot) were estimated. We used these values to derive the mass of the star, 1.02 +/- 0.03 M(circle dot).
Resumo:
The flowpaths by which water moves from watersheds to streams has important consequences for the runoff dynamics and biogeochemistry of surface waters in the Amazon Basin. The clearing of Amazon forest to cattle pasture has the potential to change runoff sources to streams by shifting runoff to more surficial flow pathways. We applied end-member mixing analysis (EMMA) to 10 small watersheds throughout the Amazon in which solute composition of streamwater and groundwater, overland flow, soil solution, throughfall and rainwater were measured, largely as part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia. We found a range in the extent to which streamwater samples fell within the mixing space determined by potential flowpath end-members, suggesting that some water sources to streams were not sampled. The contribution of overland flow as a source of stream flow was greater in pasture watersheds than in forest watersheds of comparable size. Increases in overland flow contribution to pasture streams ranged in some cases from 0% in forest to 27-28% in pasture and were broadly consistent with results from hydrometric sampling of Amazon forest and pasture watersheds that indicate 17- to 18-fold increase in the overland flow contribution to stream flow in pastures. In forest, overland flow was an important contribution to stream flow (45-57%) in ephemeral streams where flows were dominated by stormflow. Overland flow contribution to stream flow decreased in importance with increasing watershed area, from 21 to 57% in forest and 60-89% in pasture watersheds of less than 10 ha to 0% in forest and 27-28% in pastures in watersheds greater than 100 ha. Soil solution contributions to stream flow were similar across watershed area and groundwater inputs generally increased in proportion to decreases in overland flow. Application of EMMA across multiple watersheds indicated patterns across gradients of stream size and land cover that were consistent with patterns determined by detailed hydrometric sampling.
Resumo:
Rare species are one of the principal components of the species richness and diversity encountered in Dense Ombrophilous Tropical Forests. This study sought to analyze the rare canopy species within the Atlantic Coastal Forest in Rio de Janeiro State, Brazil. Six different communities were examined: Dense Ombrophilous alluvial Forest; Dense sub-montane Ombrophilous Forest; Dense Montane Ombrophilous in Serra do Mar and Serra da Mantiqueira. In each area the vegetation was sampled within forty 10 x 25 m plots alternately distributed along a linear transect. All trees with DBH (1.3 m above ground level) a parts per thousand yen5 cm were sampled. The canopy was characterized using the allometric relationship between diameter and height, and included all trees with BDH a parts per thousand yen10 cm and height a parts per thousand yen10 m. A total of 64 families, 206 genera, and 542 species were sampled, of which 297 (54.8%) represented rare species (less than one individual per hectare). The percentage of rare species varied from 34 to 50% in each of the different communities sampled. A majority of these rare trees belonged to the Rosidae, and a smaller proportion to the Dilleniidae. It was concluded that there was no apparent pattern to rarity among families, that rarity was probably derived from a number of processes (such as gap formation), and that a great majority of the rare species sampled were consistently rare. This indicates that the restricted geographic distribution and high degree of endemism of many arboreal taxa justifies the conservation of even small fragments of Atlantic Forest.
Resumo:
Multipulse rectifier topologies based on autoconnections are increasingly applied as interface stages between mains and power electronics converters. These topologies are attractive and cost-effective solutions for meeting the requirements of low total harmonic distortion of line current and high power factor. Furthermore, as only a small fraction of the total power required by the load is processed in the magnetic core, the overall resulting volume and weight are reduced. This paper proposes a mathematical analysis based on phasor diagrams that results in a single and general expression capable of unifying all delta and wye step-up or step-down autotransformer connections for 12-and 18-pulse ac-dc converters. The expression obtained allows the choice of a wide range of input/output voltage ratio for step-up or step-down autotransformer, and this general expression is also presented in a graphical form for each converter. Moreover, it simplifies the procedure for determining turn ratios and polarities for all windings of the autotransformer. A routine for easy and fast calculations is developed and validated by a design example. Finally, experimental results are presented along with comments on a 6-kW 220-V line voltage, 400-V rectified voltage, and 18-pulse delta-autoconnected prototype.
Resumo:
We studied the structure of a population of Hydromedusa maximiliani associated with a stream in Parque Estadual da Serra do Mar, Nucleo Itutinga-Piloes, southeastern Brazil, between October 2004 and October 2005. Twenty-five individuals were captured, and a population size of 43.72 +/- 23.7 individuals was estimated. This value is similar to that of the population of Parque Estadual Carlos Botelho, another Atlantic forest reserve of southeastern Brazil. Males were recaptured more frequently than females, suggesting higher activity and/or greater movement of males.