Artigos Científicos - ICEN

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2557

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Análise de aproximações das concepções presentes em questões associadas ao ensino de química aplicadas no novo ENEM com as concepções do enfoque CTS
(Universidade Federal do Pará, 2019-06) SOUZA, Jorge Raimundo da Trindade; BRITO, Licurgo Peixoto de
The National High School Examination (Enem) comprehends the evaluation of skills and competences fundamental to the exercise of citizenship, one of the objectives of the Science, Technology and Society (STS) approach. This qualitative research, which also adopts quantitative standards, has the objective of analyzing STS concepts in the issues associated to the chemistry teaching of this exam, in the period between 2009 to 2015 (new Enem), and the factors that influence these relations. For this, it was necessary to analyze the content and the structure of the questions associated to the teaching of Chemistry, examining if and how occurred the approximation of these questions with the principles of the STS educational perspective, and what conditions determine the mediation of this relation of proximity. As an instrument for analyzing the questions, the Discursive Textual Analysis (ATD) was used. Among the 156 analyzed questions, which are pertinent to the teaching of Chemistry, 46.1% did not present an approximation with the principles of the STS approach; 32.1% showed an apparent relationship with these assumptions and 21.8% were associated with the principles of the STS approach. The results showed that the questions of the new Enem presented proximity, at different levels, to the theoretical principles of the STS approach.
Acesso aberto (Open Access)
Phytosterols isolated from endophytic fungus Colletotrichum gloeosporioides (Melanconiaceae)
(Instituto Nacional de Pesquisas da Amazônia, 2016-03) CARVALHO, Josiwander Miranda; PAIXÃO, Luanna Karyna Olimpio da; DOLABELA, Maria Fâni; MARINHO, Patrícia Santana Barbosa; MARINHO, Andrey Moacir do Rosário
Endophytic fungi are fungi that colonize internal tissues of plants. There are few studies of compounds isolated from endophytic fungi of Amazon plants. Thus, the aim this study was the isolation and structural identification of sitosterol (1), stigmasterol (2), sitostenone (3), squalene (4), ergosterol (5) and ergosterol peroxide (6) from fungus Colletotrichum gloeosporioides isolated as endophytic from Virola michelli, a typical Amazon plant, used in folk medicine against skin infection. Compounds were isolated by chromatography column on silica and identified by 1 H and 13C NMR and MS. The presence of phytosterols in fungi is rare and this is the first report of the isolation of the phytosterols sitosterol, stigmasterol and sitostenone from the genus Colletotrichum.

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