16,629 research outputs found

    Low frequency measurements of synchrotron absorbing HII regions and modeling of observed synchrotron emissivity

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    Cosmic rays (CRs) and magnetic fields are dynamically important components in the Galaxy, and their energy densities are comparable to that of the turbulent interstellar gas. The interaction of CRs and Galactic magnetic fields produces synchrotron radiation clearly visible in the radio regime. Detailed measurements of synchrotron radiation averaged over the line-of-sight (LOS), so-called synchrotron emissivities, can be used as a tracer of the CR density and Galactic magnetic field (GMF) strength. Our aim is to model the synchrotron emissivity in the Milky Way using a 3 dimensional dataset instead of LOS-integrated intensity maps on the sky. Using absorbed HII regions we can measure the synchrotron emissivity over a part of the LOS through the Galaxy, changing from a 2 dimensional to a 3 dimensional view. Performing these measurements on a large scale is one of the new applications of the window opened by current low frequency arrays. Using various simple axisymmetric emissivity models and a number of GMF-based emissivity models we can simulate the synchrotron emissivities and compare them to the observed values in the catalog. We present a catalog of low-frequency absorption measurements of HII regions, their distances and electron temperatures, compiled from literature. These data show that the axisymmetric emissivity models are not complex enough, but the GMF-based emissivity models deliver a reasonable fit. These models suggest that the fit can be improved by either an enhanced synchrotron emissivity in the outer reaches of the Milky Way, or an emissivity drop near the Galactic center. State-of-the-art GMF models plus a constant CR density model cannot explain low-frequency absorption measurements, but the fits improved with slight (ad-hoc) adaptations. It is clear that more detailed models are needed, but the current results are very promising.Comment: 14 pages, 9 figures, accepted for publication in A&

    Case for diagnosis

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    Abstract We report a clinical case of a rare variant of pemphigus - pemphigus herpetiformis - which combines the clinical features of dermatitis herpetiformis with the immunological findings of pemphigus. Due to its atypical presentation, it is frequently misdiagnosed as dermatitis herpetiformis. It is basically characterized by the herpetiform pattern of skin lesions, severe pruritus and by the presence of eosinophilic spongiosis confirmed on histopathology. We call attention to the excellent response to dapsone

    Conversão de registro MARC 21 para Dublin Core na Agência de Informação Embrapa.

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    bitstream/CNPTIA/11543/1/ct80.pdfAcesso em: 28 maio 2008

    Saccharomyces cerevisiae UE-ME3 is a good strain for isoproturon biorremediation?

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    Isoproturon, an herbicide of pre- and pos-emergence of Autumn-Winter crops, persists occasionally in soil, groundwater and biological systems at levels above those established by European Directives. Saccharomyces cerevisiae UE-ME3 exposed in stationary phase to 50 and 100 mM isoproturon exhibit growth rates higher than control or exposed cells to 5 and 25 mM of this phenylurea. However, in S.cerevisiae UE-ME3 grown in the presence of 5 mM isoproturon, were observed a decrease of GSH/GSSG ratio, an increase of cytoplasmatic MDA level, GR and GPx activities, usual markers of cell damage and oxidative stress. Nevertheless, S.cerevisiae grown at 25, 50 and 100 mM isoproturon, have developed adaptive responses to this phenylurea by stabilization of its reducing environment, lipid peroxidation decrease and GR, GPx activities increase, events regulated by isoproturon level in culture medium, facts which suggest that this yeast strain can be useful on bioremediation

    Representação descritiva e temática de recursos de informação no Sistema Agência Embrapa: uso do padrão Dublin Core.

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    O artigo relata a experiência da Embrapa na utilização do padrão de metadados Dublin Core (DC) na representação descritiva e temática de recursos de informação eletrônicos. É apresentada uma descrição sucinta de cada elemento metadado, incluindo sua definição, qualificadores e valor. A adoção do padrão Dublin Core teve sua origem no âmbito de um projeto de pesquisa dedicado à organização e tratamento da informação eletrônica produzida pela Empresa, cujo produto principal é o website “Agência de Informação Embrapa”. Duas ferramentas de software foram desenvolvidas para dar suporte à atividade de representação descritiva e temática. Uma ferramenta é dedicada às rotinas de inserção, alteração, exclusão e consulta de registros na base de dados. Regras mínimas de representação descritiva, baseadas na AACR2, foram adotadas no tratamento da informação. A segunda ferramenta apóia as atividades relativas ao controle de autoridades, palavras-chaves e categorias de assunto. A representação descritiva e temática de recursos de informação utilizando o padrão Dublin Core contribui para aumentar a precisão da informação, além de diminuir as ambigüidades e inconsistências, fatores críticos de qualidade na recuperação e acesso aos conteúdos desejados

    Adult mastocytosis: a review of the Santo António Hospital 's experience and an evaluation of World Health Organization criteria for the diagnosis of systemic disease

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    BACKGROUND: Mastocytosis is a clonal disorder characterized by the accumulation of abnormal mast cells in the skin and/or in extracutaneous organs. OBJECTIVES: To present all cases of mastocytosis seen in the Porto Hospital Center and evaluate the performance of World Health Organization diagnostic criteria for systemic disease. METHODS: The cases of twenty-four adult patients with mastocytosis were reviewed. Their clinical and laboratorial characteristics were assessed, and the properties of the criteria used to diagnose systemic mastocytosis were evaluated. RESULTS: The age of disease onset ranged from 2 to 75 years. Twenty-three patients had cutaneous involvement and 75% were referred by dermatologists. Urticaria pigmentosa was the most common manifestation of the disease. One patient with severe systemic mast cell mediator-related symptoms showed the activating V560G KIT mutation. The bone marrow was examined in 79% of patients, and mast cell immunophenotyping was performed in 67% of the participants. Systemic disease was detected in 84% of cases, and 81% of the sample had elevated serum tryptase levels. All the diagnostic criteria for systemic mastocytosis had high specificity and positive predictive value. Bone marrow biopsy had the lowest sensitivity, negative predictive value and efficiency, while the highest such values were observed for mast cell immunophenotyping. Patients were treated with regimens including antihistamines, sodium cromoglycate, alpha-interferon, hydroxyurea and phototherapy. CONCLUSIONS: Cutaneous involvement is often seen in adult mastocytosis patients, with most individuals presenting with indolent systemic disease. Although serum tryptase levels are a good indicator of mast cell burden, bone marrow biopsy should also be performed in patients with normal serum tryptase, with flow cytometry being the most adequate method to diagnose systemic disease

    Atuação do bibliotecário no Sistema Agência de Informação da Embrapa: perfil profissional.

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    Catalogação de recursos. Integridade da informação. Clareza da informação. Precisão. Lógica. Consistência. Classificação e categorização de assunto. Indexação.bitstream/CNPTIA/9180/1/COMNICADOTEC7.pdfAcesso em: 29 maio 2008

    Sezary Syndrome presenting with leonine facies and treated with low-dose subcutaneous alemtuzumab

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    Cutaneous T-cell lymphomas (CTCL) comprise a group of diseases characterized by the accumulation of malignant T cells within the skin. Sezary syndrome represents an aggressive form of CTCL, in which the skin is diffusely affected and the peripheral blood is involved. It is characterized by the triad of generalized erythroderma, lymphadenopathy, and neoplastic T cells (Sezary cells) in the skin, lymph nodes, and peripheral blood. Leonine facies is rare and corresponds to the morphologic manifestation of diffuse dermal infiltration of the face. It can occur in cutaneous T-cell lymphomas that progress during years without therapy. We present the case of a 54-year-old man with Sezary syndrome presenting with leonine facies, unresponsive to conventional therapies; he exhibited a promising response to subcutaneous low-dose alemtuzumab
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