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Avaliação do potencial fitotóxico de frações e subfrações de folhas, cascas de caule e raízes de Ocotea pulchella e dos compostos salicilato de benzila e benzoato de benzila sobre espécies invasoras
(Universidade Federal de São Carlos, 2020-12-21) Fuentes, Luis Felipe García; Gualtieri, Sonia Cristina Juliano; https://lattes.cnpq.br/9973185407856723; https://lattes.cnpq.br/5723616089076998
Plants synthesize a wide variety of chemicals in response to biotic and abiotic stresses. These substances are usually associated with plant defense processes against herbivores and pathogens. These substances, derived from secondary metabolism are known as allelochemicals. The species of the Lauraceae family have the potential to produce secondary metabolites with herbicidal properties. Thus, the objective of this work was to evaluate the phytotoxic potential of extracts and subfractions of the species Ocotea pulchella, as well as of the synthetic compounds benzyl salicylate and benzyl benzoate on target species. For this, bioassays were carried out with coleoptiles of Triticum aestivum and bioassays of germination and initial growth of invasive species of agricultural crops. The concentrations of 0.8 mg.mL-1, 0.4 mg.mL-1 and 0.2 mg.mL-1 were used for hexane extracts, ethyl and aqueous acetates, of leaves, stem barks and roots as well as well as for the subfractions of the ethyl acetate extract of rainy season leaves from O. pulchella. For the synthetic compounds, concentrations of 10-3 M, 3•10-4 M, 10-4 M, 3•10-5 M and 10-5 M were used in bioassays with T. aestivum coleoptiles; whereas for the initial growth bioassays the concentrations of 10-3 M, 10-4 M e 10-5 M were used. All 18 extracts of O. pulchella inhibited the growth of T. aestivum coleoptiles at least in the highest concentration tested. In general, the group of ethyl acetate extracts (leaves, stem and root) from O. pulchella showed the highest phytotoxic activity in the target species. The benzyl salicylate and benzyl benzoate compounds showed strong inhibitory activity on the growth of T. aestivum coleoptiles, being even superior to the herbicide mainly at concentrations 3•10-5 M and 10-5 M. These compounds also showed an inhibitory effect on the bioindicator species Lactuca sativa, Solanum lycopersicum, Allium cepa and T. aestivum and on the invasive species Euphorbia heterophylla and Megathyrsus maximus. E. heterophylla was the species most affected by the action of both compounds in all evaluated parameters and in some parameters the inhibitory effect of these compounds was equal to that exerted by the herbicide, mainly in the root system. All eight subfractions obtained from the ethyl acetate extract of leaves from the rainy season significantly inhibited the growth of T. aestivum coleoptiles in the highest concentration (0.8 mg. ML-1) and seven of these also did in the other two concentrations (0, 4 mg. ML-1 and 0.2 mg. ML-1). In the initial growth bioassays, four subfractions were tested (A1, A2, A3 and A4) where subfractions A1 and A2 exerted the highest values of inhibition in the growth of the root and aerial part of the species E. heterophylla and M. maximus. In addition, in the species E. heterophylla, subfractions A1 and A2 exerted inhibition values statistically equal to those exerted by the herbicide in all concentrations tested both in the aerial part and in the root system. However, the highest concentration of subfraction A1 in the roots was higher than that observed by the herbicide at the same concentration. Thin layer chromatography was performed and the presence of benzyl salicylate and benzyl benzoate was verified in subfraction A1, such compounds are reported in the literature as compounds with phytotoxic potential responsible for the phytotoxic activity of O. pulchella. The reduction in the growth of the root system of E. heterophylla seedlings may be related to the decrease in the elongation of the metaxylem cells submitted to the subfractions of the ethyl acetate extract of leaves of the O. pulchella species. Therefore, it is possible to conclude that the O. pulchella species as well as the synthetic compounds benzyl salicylate and benzyl benzoate have phytotoxic potential.
A importância da Curadoria Digital para a gestão de dados de pesquisa
(Universidade Federal de São Carlos, 2020-12-21) Silva, Larissa Alves da; Arakaki, Ana Carolina Simionato; https://lattes.cnpq.br/9896600626524397; https://lattes.cnpq.br/5714545457389700
Period of technological advent from the information age. Time-space that, concomitantly leads to changes in science and in the elaboration of scientific research. Data generated in mass exponentially that encompass all areas of knowledge. By this parameter, the present research performs in qualitative scope of theoretical-applied nature, in order to correlate concepts of Digital Curation and Research Data Management. Indeed, data when managed, understood, treated, preserved and reused in a way proper, serve as informational resource for the dissemination of science and development of research and scientific knowledge. Intends to analyze and reflect on the question: how the two approaches correlate and together, link to the “data” domain for the dissemination of scientific information and knowledge? In that domain, under development, explains about Digital Curation and the importance for Research Data Management. Performs mapping about the concepts of Digital Curation and Research Data Management. As a result, it appears that the set of identified concepts along the mapping presents that these dialogue with each other and complement each other, as well as among the definitions of Research Data Management, highlights the great link with the performance of the librarian as highly relevant in relation to service offering, use of tools, in addition to plans and methods for research data management. It is observed that the analyzes suggest that there is growing interest in the scientific and academic community in relation to Digital Curation and Research Data Management, even though they are an evolving concept, manifesting during scientific propagation. It is concluded that recognition of the Digital Curation and its importance for Research Data Management which consists of the fact that methods used by the Digital Curation process, as stages of archiving and digital preservation, they also include steps in the process with the purpose of giving attention to the creation and effective management of research data, making data subject to interpretation, use, reuse and access and effective management and subsequent data sharing, increase scientific and technological progress, assist research and researchers to progress scientifically.
O ensino das partículas elementares a partir de uma sequência didática
(Universidade Federal de São Carlos, 2020-12-21) Moura Júnior, Orlando Leite de; Silva, Fernanda Keila Marinho da; https://lattes.cnpq.br/6390725197649567; Cruz, Tersio Guilherme de Souza; https://lattes.cnpq.br/0705292304279277; https://lattes.cnpq.br/7741040395733465
In this academic work we present the development of the study, elaboration, application and verification of the data of a Didactic Sequence (SD) that aims to assist students learning in the third year of high school (EM), in a state public school in the interior of São Paulo. The content to be studied are the Elementary Particles (PE) – basic components of matter – and their interactions, an integral part of the theme of Modern and Contemporary Physics (FMC). The SD was supported by the Theory of Meaningful Learning (TAS) and by the State of São Paulo High School Curriculum. The pedagogical activities present on the SD are clarified in four distinct Didactic Units (UD) that aim to mitigate the apparent difficulties of teaching and learning contents related to the subject of Physics, mainly FMC. The activities were followed by formative and summative assessments (taken at the end of the SD). We thus hope to be pertinent to the pedagogical context and to contribute to the continuous search for an increasingly adequate and effective teaching/learning relationship.