Carbon fiber non-crimp multi-axial reinforcement and epoxy mono-component system composite: fatigue behavior

Fiber reinforced polymer composites have been widely applied in the aeronautical field. However, composite processing, which uses unlocked molds, should be avoided in view of the tight requirements and also due to possible environmental contamination. To produce high performance structural frames meeting aeronautical reproducibility and low cost criteria, the Brazilian industry has shown interest to investigate the resin transfer molding process (RTM) considering being a closed-mold pressure injection system which allows faster gel and cure times. Due to the fibrous composite anisotropic and non homogeneity characteristics, the fatigue behavior is a complex phenomenon quite different from to metals materials crucial to be investigated considering the aeronautical application. Fatigue sub-scale specimens of intermediate modulus carbon fiber non-crimp multi-axial reinforcement and epoxy mono-component system composite were produced according to the ASTM 3039 D. Axial fatigue tests were carried out according to ASTM D 3479. A sinusoidal load of 10 Hz frequency and load ratio R = 0.1. It was observed a high fatigue interval obtained for NCF/RTM6 composites. Weibull statistical analysis was applied to describe the failure probability of materials under cyclic loads and fractures pattern was observed by scanning electron microscopy. (C) 2010 Published by Elsevier Ltd.

Arranjo de plantas para diferentes híbridos de milho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The temperature coefficient of the optical path length as a function of the temperature in different optical glasses

An interferometric technique was used to determine the temperature coefficient of the optical path length (dS/dT) as a function of the temperature in several optical glasses. The temperature range was between 25degreesC and 180degreesC. The studied samples included undoped and doped oxide glasses, such as low silica calcium aluminosilicate, phosphates, borates and also chalcogenides. The oxide glasses had dS/dT between 10 X 10(-6) K-1 and 20x10(-6) K-1, while for the chalcogenides, these were around 70 x 10(-6)K(-1). The results showed that dS/dTs increased with the temperature in all samples. For samples doped with Nd the dS/dT values were found to be independent of concentration. on the other hand, for the phosphate glass doped with Cr, dS/dT increased about 5% when compared with the Nd doped one. In conclusion, the used interferometric method, which is a considerably simpler and a lower cost technique, and is a useful tool to measure dS/dT in semi-transparent glasses as a function of the composition and temperature. (C) 2004 Elsevier B.V. All rights reserved.

Conservative management of pituitary tumor apoplexy

A apoplexia pituitária é uma rara síndrome neuroendócrina causada, na maioria dos casos, pela hemorragia ou enfarte de um adenoma pituitário preexistente. O tratamento recomendado é variável; alguns autores defendem a descompressão cirúrgica do tumor em regime de urgência, enquanto outros sugerem que o tratamento conservador pode levar à recuperação da função neuroftalmológica. Descrevemos os casos de dois pacientes com apoplexia pituitária que apresentaram macroadenomas clinicamente não secretores e hipopituitarismo, incluindo hipogonadismo. Ambos foram submetidos ao tratamento conservador, sem cirurgia, e houve a remissão do tumor.

Identificação de enfermidades agudas causadas por animais e plantas em ambientes rurais e litorâneos: auxílio à prática dermatológica

FUNDAMENTOS: Nos últimos anos, existe um aumento progressivo do contato de moradores urbanos com ambientes selvagens devido a atividades de lazer. Com isso, algumas dermatites pouco conhecidas podem ser observadas nas clínicas privadas e ambulatórios dermatológicos, especialmente nos inícios de semana e finais de férias. OBJETIVOS: Obter e fornecer informações para dermatologistas sobre o problema. PACIENTES E MÉTODOS: O autor observou, em adultos e crianças, dermatites agudas associadas a plantas ou animais em Ubatuba, cidade litorânea de São Paulo, por dois meses (junho/julho de 2006) e na Faculdade de Medicina de Botucatu, também por dois meses (junho/julho de 2007). RESULTADOS: Foram observados 25 pacientes na área rural e 43 na área litorânea nas condições estabelecidas. em áreas rurais, foram mais observadas fitofotodermatites e picadas de insetos, enquanto em áreas litorâneas traumas por ouriços-do-mar e fitofotodermatites predominaram; entretanto, em ambas as áreas ocorreram outros acidentes de difícil identificação na prática diária. CONCLUSÕES: Devemos estar atentos ao fato de o paciente procurar o dermatologista somente após as fases agudas dos acidentes. Informações sobre as enfermidades mais comuns e suas características podem ser muito úteis para a prática nos consultórios. O autor sugere uma tabela algorítmica para auxílio diagnóstico.

Antioxidant supplementation and premature rupture of the membranes: a planned secondary analysis

OBJECTIVE: The purpose of this study was to determine if antioxidant supplementation during pregnancy reduces the incidence of premature rupture of the membranes (PROM).STUDY DESIGN: A placebo-controlled, double-blind trial was conducted. PROM and preterm PROM (PPROM) were planned secondary outcomes of the trial. Women between 12(0/7) and 19(6/7) weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomized to daily treatment with both vitamin C (1000 mg) and E (400 IU) or placebo.RESULTS: Outcome data for PROM were available for 697 of 739 patients. The rates of PROM (37/349 [10.6%] vs 19/348 [5.5%]; adjusted risk ratio [RR] 1.89 [95.42% CI, 1.11-3.23]; P = .015), and PPROM (16/349 [4.6%] vs 6/348 [1.7%]; RR 2.68 [1.07-6.71]; P = .025) were increased in the antioxidant group.CONCLUSION: Contrary to expectations, vitamins C and E supplementation in this dose combination may be associated with an increased risk of PROM and PPROM.

Revascularização clínica e intervencionista no acidente vascular cerebral isquêmico agudo: opinião nacional

The Brazilian Stroke Society constituted a committee composed by specialists from different areas of Brazil that emitted a viewpoint called National Opinion, considering the interventional procedures and thrombolysis in the treatment of the acute ischemic stroke. This study presents the conclusions of this committee.