33 research outputs found

    Vehicle emissions and PM2.5 mass concentrations in six Brazilian cities

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    In Brazil, the principal source of air pollution is the combustion of fuels (ethanol, gasohol, and diesel). In this study, we quantify the contributions that vehicle emissions make to the urban fine particulate matter (PM2.5) mass in six state capitals in Brazil, collecting data for use in a larger project evaluating the impact of air pollution on human health. From winter 2007 to winter 2008, we collected 24-h PM2.5 samples, employing gravimetry to determine PM2.5 mass concentrations; reflectance to quantify black carbon concentrations; X-ray fluorescence to characterize elemental composition; and ion chromatography to determine the composition and concentrations of anions and cations. Mean PM2.5 concentrations in the cities of SĂŁo Paulo, Rio de Janeiro, Belo Horizonte, Curitiba, Porto Alegre, and Recife were 28, 17.2, 14.7, 14.4, 13.4, and 7.3 Όg/m3, respectively. In SĂŁo Paulo and Rio de Janeiro, black carbon explained approximately 30% of the PM2.5 mass. We used receptor models to identify distinct source-related PM2.5 fractions and correlate those fractions with daily mortality rates. Using specific rotation factor analysis, we identified the following principal contributing factors: soil and crustal material; vehicle emissions and biomass burning (black carbon factor); and fuel oil combustion in industries (sulfur factor). In all six cities, vehicle emissions explained at least 40% of the PM2.5 mass. Elemental composition determination with receptor modeling proved an adequate strategy to identify air pollution sources and to evaluate their short- and long-term effects on human health. Our data could inform decisions regarding environmental policies vis-Ă -vis health care costs

    Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil

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    Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30 years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars

    A taxonomic bibliography of the South American snakes of the Crotalus durissus complex (Serpentes, Viperidae)

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    Treatment of human acute schistosomiasis with oxamniquine induces an increase in interferon-Îł response to Schistosoma mansoni antigens

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    Patients with acute schistosomiasis were studied before and after oxamniquine treatment. They had been exposed to cercariae 5 to 9 weeks before, and presented compatible clinical manifestations, eosinophilia, and high levels of total IgE. Interferon-g (IFN-Îł) and interleukin-4 were measured by ELISA in whole blood samples under soluble egg antigen or soluble adult worm preparation stimulation. After treatment, the reduction of leukocytosis and eosinophilia were not significant, but total IgE levels decreased significantly, in contrast to IFN-Îł levels that were significantly increased. The oxamniquine treatment of acute schistosomiasis patients is followed by an improvement of a Th1 response in vitro. If this response has a protective aspect is unknown, and some investigations need to be realized

    Identificação de contaminação bacteriana no sabão líquido de uso hospitalar

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    O estudo realizou a anĂĄlise bacteriolĂłgica de sabĂ”es lĂ­quidos utilizados para lavagem das mĂŁos dos profissionais de saĂșde. Trata-se de estudo exploratĂłrio transversal, desenvolvido nas unidades de internação de hospital de mĂ©dio porte em Fortaleza/CE. Os dados foram colhidos no perĂ­odo de maio a julho de 2007. Do total de 59 frascos com sabĂŁo lĂ­quido, 33 continham os seguintes microorganismos: Burkholderia cepacia (n=14), Pseudomonas putidas (9), Pseudomonas aeruginosa (3), Klebsiella pneumoniae (3), Enterobacter cloacae (2), Pseudomonas luteola (2). As unidades com maior nĂșmero de amostras contaminadas foram a clĂ­nica cirĂșrgica (n=7) e a clĂ­nica dermatolĂłgica (n=4). A contaminação tambĂ©m foi verificada em frasco original do mesmo lote de sabĂŁo lĂ­quido usado para abastecer as saboneteiras. Podemos concluir ser necessĂĄrio disciplinar e controlar a qualidade desses produtos nas linhas de produção tanto quanto nas fases de uso nos serviços de saĂșde, sobretudo porque sua utilidade se presta Ă  prevenção de infecção hospitalar
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