1,453 research outputs found

    Dengue epidemic in Belém, Pará, Brazil, 1996-97.

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    We describe clinical and epidemiologic findings during the first epidemic of dengue fever in Belém, Pará State, Brazil, in 1996-97. Of 40,237 serum samples, 17,440 (43%) were positive for dengue by virus isolation or serologic testing. No hemorrhagic cases or deaths were reported. Mycobacterium tuberculosi

    Cell walls of the dimorphic fungal pathogens Sporothrix schenckii and Sporothrix brasiliensis exhibit bilaminate structures and sloughing of extensive and intact layers

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    This work was supported by the Fundação Carlos Chagas de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), grants E-26/202.974/2015 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), grants 229755/2013-5, Brazil. LMLB is a senior research fellow of CNPq and Faperj. NG acknowledged support from the Wellcome Trust (Trust (097377, 101873, 200208) and MRC Centre for Medical Mycology (MR/N006364/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Fuel Starvation: irreversible degradation mechanisms in PEM Fuel Cells

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    PEM fuel cell operates under very aggressive conditions in both anode and cathode. Failure modes and mechanism in PEM fuel cells include those related to thermal, chemical or mechanical issues that may constrain stability, power and lifetime. In this work, the case of fuel starvation is examined. The anode potential may rise to levels compatible with the oxidization of water. If water is not available, oxidation of the carbon support will accelerate catalyst sintering. Diagnostics methods used for in-situ and ex-situ analysis of PEM fuel cells are selected in order to better categorize irreversible changes of the cell. Electrochemical Impedance Spectroscopy (EIS) is found instrumental in the identification of fuel cell flooding conditions and membrane dehydration associated to mass transport limitations / reactant starvation and protonic conductivity decrease, respectively. Furthermore, it indicates that water electrolysis might happen at the anode. Cross sections of the membrane catalyst and gas diffusion layers examined by scanning electron microscopy indicate electrode thickness reduction as a result of reactions taking place during hydrogen starvation. Catalyst particles are found to migrate outwards and located on carbon backings. Membrane degradation in fuel cell environment is analyzed in terms of the mechanism for fluoride release which is considered an early predictor of membrane degradation

    Ocorrência recente de infecção humana por arbovirus Rocio na região do Vale do Ribeira

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    The presence of IgM antibodies to Rocio in sera of two children from rural area of Ribeira Valley, Brazil, was detected by MAC-ELISA. This new arbovirus of the Flaviviridae family was responsible for an extensive encephalitis epidemic that occurred in the region in 1975-1977. Since 1980 no human disease caused by this virus has been diagnosed. An improvement on surveillance of Rocio infections and on the researches for virus identification in suspected vectors and reservoirs is necessary.Descreve-se o achado sorológico de anticorpos IgM para vírus Rocio em duas crianças da área rural do Vale do Ribeira, Estado de São Paulo. O vírus Rocio foi responsável por extensa epidemia de encefalite na região em 1975-1977. Desde 1980 não têm sido diagnosticados casos de doença. Impõe-se a ativação de medidas dirigidas à vigilância epidemiológica desta arbovirose

    Adductor squeeze test and groin injuries in elite football players: A prospective study

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    during the competitive season of professional football teams. Design: Prospective Cohort study. Setting: Controlled laboratory environment. Participants: Seventy-one players volunteered to participate. Main outcome measures: In the pre-season, maximal hip adductor strength was measured by means of the isometric adductor squeeze test. Hip adductor strength, normalized by body mass, was compared between players who suffered a groin injury (n ¼ 18) vs uninjured players (n ¼ 53). Risk ratios (RR) were used to evaluate the likelihood of players to suffer this type of injury. Results: Most of the reported groin injuries occurred during competitive matches (5.5 per 1000 match hours). Maximal isometric hip adductor strength was lower in the groin-injured group compared with their uninjured counterparts (429.8 ± 100 vs 564 ± 58.7 N, d¼ 1.58 and 5.40 ± 1.27 vs 7.71 ± 0.89 N/kg, d¼ 1.88, respectively). Results revealed that values of maximal isometric adductor strength lower than 465.33 N increased the probability to suffer a groin injury by 72%. Furthermore, values of force relative to body mass lower than 6.971 N/kg increased the probability to suffer a groin injury by 83%. Conclusion: The assessment of Hip adductor strength, in addition to other measurements, might help practitioners to determine the probability of suffering an overuse groin injuries in elite football players.info:eu-repo/semantics/publishedVersio

    West Nile virus infection in the golden hamster (Mesocricetus auratus): a model for West Nile encephalitis.

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    This report describes a new hamster model for West Nile (WN) virus encephalitis. Following intraperitoneal inoculation of a New York isolate of WN virus, hamsters had moderate viremia of 5 to 6 days in duration, followed by the development of humoral antibodies. Encephalitic symptoms began 6 days after infection; about half the animals died between the seventh and 14th days. The appearance of viral antigen in the brain and neuronal degeneration also began on the sixth day. WN virus was cultured from the brains of convalescent hamsters up to 53 days after initial infection, suggesting that persistent virus infection occurs. Hamsters offer an inexpensive model for studying the pathogenesis and treatment of WN virus encephalitis

    LUCIS:a learning experience to improve lifetime and operating strategies in low power PEM fuel cells

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    LUCIS, a demonstration project co-financed by the Innovation Agency in Portugal (AdI), was carried out in the framework of the DEMTEC Programme (Incentives to Technologically Innovative Pilot Systems). Its main goals were: Validate the reliability of proton exchange membrane fuel cells (PEMFC) when used in practical situations and the competitive advantages that these solutions can represent compared to conventional solutions; Evaluate impacts associated with the use of hydrogen and the benefits to business competitiveness. This project allowed a learning experience in real applications of low power PEMFC. Demonstrations were grouped in two large categories that covered several applications of PEMFC. The prototypes used were produced by SRE (Portugal) and were specifically designed to be used in small power applications, portable, traction or stationary. In this work, the technological validation was carried out for different stacks with power from 10 to 100W. Hydrogen was supplied by compressed gas bottles and metallic hydrides. All the fuel cells were previously characterized in specialized laboratories. Recommendations were drawn for every application in order to improve fuel cell lifetime and operating strategies
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