581 research outputs found

    Neurite Outgrowth Inhibitors in Gliotic Tissue

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    Erros em Testes e Medidas

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    Parece impraticável, ou demasiadamente idealista, esperar que pesquisas envolvendo testes e medidas sejam apresentadas totalmente livres de erros. o maior problema não é eliminar o erro, ao contrá­rio, é evitar o erro que possa resultar em má interpretação dos re­sultados. em uma consideração mais ampla, é possível classificar erros em pesquisa como sendo resultantes de : (a) falta de lógica; (b) generalizações sem justificativa; e (c) falta de exatidão nas medidas. cada um destes aspectos têm recebido consideração de alguma forma, por parte de vários autores (Brozek & Alexander, 1947; Cureton, Wickens & Elder, 1935). O propósito da presente discussão é o de, primeiramente, consi­derar o erro de medidas, sua avaliação e seu controle

    Generación de una Línea Transgénica de Pez Cebra para Estudiar la Remodelación de Uniones Adherentes

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    El remodelado dinámico de los contactos adhesivos intercelulares o uniones adherentes (UAs) mediado por la proteína cadherina epitelial E (cadh-E) es clave para coordinar los movimientos migratorios celulares durante la embriogénesis animal. Debido a la simplicidad estructural y a la accesibilidad experimental, el embrión de pez cebra (Danio rerio) se ha establecido como un modelo para estudiar migración celular y para entender la dinámica del tráfico vesicular y distribución de cadh-E en UAs. En el presente proyecto se propuso generar una línea transgénica estable de pez cebra (cadh-E-KikGR) para la expresión de cadh-E fusionada a la proteína fotoconvertible KikGR para visualizar in vivo la remodelación de UAs. En una primera etapa se analizó la expresión endógena nativa de cadh-E y se comparó con la expresión transgénica de cadh-E fusionada a la proteína reportera fluorescente GFP (Green Fluorescent Protein) como una primera estrategia de monitoreo. Se observó que cadh-E no se localiza en membranas como la cadh-E endógena por lo que la fusión no sería funcional una vez expresada en el embrión. El clonado de KikGR, de menor tamaño, en reemplazo de GFP en el vector final de expresión permitirá la obtención del embrión transgénico de interés

    Damage Function for Historic Paper: Part II

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    Background As a result of use of library and archival documents, defined as reading with handling in the context of general access, mechanical degradation (wear and tear) accumulates. In contrast to chemical degradation of paper, the accumulation of wear and tear is less well studied. Previous work explored the threshold of mechanical degradation at which a paper document is no longer considered to be fit for the purpose of use by a reader, while in this paper we explore the rate of accumulation of such damage in the context of object handling. Results The degree of polymerisation (DP) of historic paper of European origin from mid-19th–mid-20th Century was shown to affect the rate of accumulation of wear and tear. While at DP > 800, this accumulation no longer depends on the number of handlings (the process is random), a wear-out function could be developed for documents with DP between 300 and 800. For objects with DP < 300, one large missing piece (i.e. such that contains text) developed on average with each instance of handling, which is why we propose this DP value as a threshold value for safe handling. Conclusions The developed model of accumulation of large missing pieces per number of handlings of a document depending on DP, enables us to calculate the time required for an object to become unfit for use by readers in the context of general access. In the context of the average frequency of document use at The UK National Archives (Kew), this period is 60 years for the category of papers with DP 300, and 450 years for papers with DP 500. At higher DP values, this period of time increases beyond the long-term planning horizon of 500 years, leading to the conclusion that for such papers, accumulation of wear and tear is not a significant collection management concern

    Assessing the sensitivity of data-limited methods for resources in the Atlantic waters

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    ICES Annual Science Conference 2021, online 6-10 SeptemberLength-based methods have been widely applied to estimate biological parameters and to under-stand the dynamics of marine resource populations within the category of data-limited stocksThe authors thank the financial support of the project IMPRESS (RTI2018-099868-B-I00) project, ERDF, Ministry of Science, Innovation and Universities - State Research Agency, and also of GAIN (Xunta de Galicia), GRC MERVEX (nº IN607-A 2018-4)N

    Applying length-based assessment methods to fisheries resources of the Bay of Biscay and Atlantic Iberian Waters: stock status and parameters sensitivity

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    ASLO 2021 Aquatic Sciences Virtual Meeting, 22–27 June 2021Length-based methods have been widely applied to estimate biological parameters and to understand the dynamics of marine resource populations within the category of data-limited stocksProject IMPRESS (RTI2018-099868-B-I00), ERDF, Ministry of Science, Innovation and Universities - State Research Agency, and also of GAIN (Xunta de Galicia), GRC MERVEX (nº IN607-A 2018-4)N

    Cross‐sectional study about impact of parental smoking on rhinitis symptoms in children

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    [Abstract] Objective. Assess the prevalence of rhinitis and exposure to environmental tobacco smoke (ETS) of children in our community and its relationship with symptoms of rhinitis Methods (design, setting, participants, main outcome measures). Cross‐sectional study using questionnaire on rhinitis of the International Study of Asthma and Allergies in Childhood, in children (6‐7 years) and adolescents (13‐14 years). Categories: “rhinitis ever”, “recent rhinitis”, “recent rhinoconjunctivitis”, “severe rhinoconjunctivitis”. Parental smoking: (i) neither parent smokes; (ii) only the mother smokes; (iii) only the father smokes; and (iv) both parents smoke. Odds ratio of the prevalence of symptoms of rhinitis according to ETS exposure was calculated using logistic regression. Results. 10 690 children and 10 730 adolescents. The prevalence of “rhinitis ever” in children: 29.4%, “recent rhinitis” 24%, “recent rhinoconjunctivitis” 11.5% and “severe rhinoconjunctivitis” 0.1%. In adolescents: 46.2%, 34.5%, 16.2% and 0.2%, respectively. Environmental tobacco smoke exposure in the home occurred in 51% of cases. Parental smoking was associated with a higher prevalence of forms of rhinitis in adolescents when only the mother was a smoker. In children when both parents were smokers. Conclusion. Rhinitis is highly prevalent in our community. Environmental tobacco smoke exposure is still very common. The relationship between ETS and rhinitis symptoms in children of this community is not as robust as that found for asthma
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