9 research outputs found

    Valorização do patrimônio científico e tecnológico brasileiro: descobrindo conjuntos de objetos de C&T pelo Brasil

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    Most of Brazil's science and technology (S&T) heritage has yet to be tracked down. The knowledge amassed on the topic is still limited, and there is a real risk that Brazilian science and technology objects may already have been modernized or discarded. A research project was developed in the last four years including several initiatives to preserve this kind of heritage, as such: a national survey to build up a picture of the current state of this heritage; studies concerning heritage protection legislation of some countries, including Brazil; and two case studies of collections of S&T objects (Observatório do Valongo and Colégio Pedro II). This paper presents an overview of the results obtained in the several initiatives of preservation undertaken. The survey is divided into different areas of knowledge and different time frames. As such, we are interested in sets of objects from the exact sciences, the different engineering specialties, as well as geography, geology and oceanography, which were manufactured in or before the 1960s. A registration form was prepared which was adapted from a form used in surveys of collections of this kind in Portugal. Sets of objects have been identified at museums, universities and research institutes. From the results, it could be observed that: the best preserved collections are at the few museums devoted to the area, but the universities hold most of the artifacts and the overwhelming majority of the objects were made in the twentieth century.A maior parte dos bens que constituem o patrimônio cultural da Ciência e Tecnologia (C&T) está para ser descoberta. O conhecimento acumulado sobre o tema ainda é limitado e há um risco real de que os objetos já tenham sido modernizados ou descartados. Nos últimos quatro anos, desenvolveu-se um projeto de pesquisa, envolvendo várias iniciativas para preservar este tipo de patrimônio: um levantamento nacional para construir um panorama do estado atual desse patrimônio; estudos sobre a legislação de proteção ao patrimônio de alguns países, inclusive o Brasil; e dois estudos de caso de coleções de objetos de C&T (Observatório do Valongo e Colégio Pedro II, ambos no Rio de Janeiro). Este artigo apresenta uma visão geral dos resultados obtidos e, em especial, dos levantamentos de conjuntos de objetos de C&T. Utilizou-se um recorte em relação a áreas do conhecimento e período histórico, compreendendo objetos pertencentes à s ciências exatas, à s diferentes especialidades de engenharia, bem como geografia, geologia e oceanografia, e fabricados até 1960. A partir da adaptação de um formulário usado em pesquisas similares em Portugal, elaborou-se uma ficha de registro, que permitiu identificar conjuntos de objetos em museus, universidades e institutos de pesquisa. Pôde-se, com isso, observar que as coleções mais bem preservadas estão nos poucos museus dedicados à área, enquanto as universidades detêm a maior parte dos artefatos, e que a esmagadora maioria dos objetos foi produzida no século XX

    Physique impériale: cabinet de physique du Lycée Impérial de Périgueux

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    La chevelure dans la littérature et l’art du Moyen Âge

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    Ce volume rassemble les 27 contributions des Actes du colloque du CUER MA (2003) dans divers domaines de la civilisation du Moyen Age : littérature, peinture, médecine, hygiène, cosmétique, mode, religion... Il n'est de chevelure qu'humaine. Située au chef du corps, elle est métonymique de celui ou celle qui l'offre naïvement aux regards ou bien en joue ou encore la couvre ou s'en prive. Sa couleur, la façon dont elle est arrangée ou dérangée, ornée ou tondue, sont des signes qu'on perçoit d'emblée ou qu'il faut interpréter. Elle dénote une nature, un âge, une appartenance au monde de la lumière ou des ténèbres. Fixée en boucles menues, retenue par une tresse, galonnée d'or, sagement (ou follement !) couverte, teinte ou postiche, déployée, déferlant parfois jusqu'aux pieds pour couvrir la nudité, sauvagement ébouriffée, arrachée en signe de deuil, rasée, blessée d'une tonsure, elle signale le rapport que l'individu entretient avec les normes de la société a laquelle il appartient. Parfois il suffit d'un cheveu (d'or !) pour dire l'amour d'une Dame ou, métaphoriquement, les subtilités d'un art d'écrire

    The LMP1 oncogene of EBV activates PERK and the unfolded protein response to drive its own synthesis

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    The oncogene latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) without a ligand drives proliferation of EBV-infected B cells. Its levels vary in cells of clonal populations by more than 100-fold, which leads to multiple distinct activities of the oncogene. At intermediate levels it drives proliferation, and at high levels it inhibits general protein synthesis by inducing phosphorylation of eukaryotic initiation factor 2α (eIF2α). We have found that LMP1 activates PERK to induce phosphorylation of eIF2α, which upregulates activating transcription factor 4 (ATF4) expression. ATF4, in turn, transactivates LMP1's own promoter. LMP1 activates not only PERK but also inositol requiring kinase 1 (IRE1) and ATF6, 3 pathways of the unfolded protein response (UPR). Increasing expression levels of LMP1 induced a dose-dependent increase in IRE1 activity, as measured by its “splicing” of XBP-1. These infected B cells secrete immunoglobins independent of the levels of LMP1, indicating that only a threshold level of XBP-1 is required for the secretion. These findings indicate that LMP1's activation of the UPR is a normal event in a continuum of LMP1's expression that leads both to stimulatory and inhibitory functions and regulates the physiology of EBV-infected B cells in multiple, unexpected modes

    Molecular Pathways in Virus-Induced Cytokine Production

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    Virus infections induce a proinflammatory response including expression of cytokines and chemokines. The subsequent leukocyte recruitment and antiviral effector functions contribute to the first line of defense against viruses. The molecular virus-cell interactions initiating these events have been studied intensively, and it appears that viral surface glycoproteins, double-stranded RNA, and intracellular viral proteins all have the capacity to activate signal transduction pathways leading to the expression of cytokines and chemokines. The signaling pathways activated by viral infections include the major proinflammatory pathways, with the transcription factor NF-κB having received special attention. These transcription factors in turn promote the expression of specific inducible host proteins and participate in the expression of some viral genes. Here we review the current knowledge of virus-induced signal transduction by seven human pathogenic viruses and the most widely used experimental models for viral infections. The molecular mechanisms of virus-induced expression of cytokines and chemokines is also analyzed
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