1,930 research outputs found

    Nectandra grandiflora By-Products Obtained by Alternative Extraction Methods as a Source of Phytochemicals with Antioxidant and Antifungal Properties

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    Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75–65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth.This research was financially supported by the Department of Education of Basque Government (IT1008-16) and by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq process 454447/2014-0). Authors would like to thanks the CNPq for research grants received by Berta Maria Heinzmann, Ph.D. scholarship (process 203796/2014-4) granted to Daniela Thomas da Silva and the Basque Government for scholarship of young researchers training granted to Rene Herrera

    EFEITO DA SAZONALIDADE SOBRE O RENDIMENTO DO ÓLEO ESSENCIAL DE Piper gaudichaudianum KUNTH

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    Piper gaudichaudianum Kunth (Piperaceae) is widely distributed throughout Brazil. In addition to its ecological importance, it is used in folk medicine and a great number of its biological activities have been already proved. Thus, the aim of this research was to investigate the effect of seasonality on the content of essential oil (EO) in leaves of Piper gaudichaudianum and ascertain the possible influence of the drying process of the plant material in the yield of this extractive. Leaves were randomly collected from individuals of a native population in Santa Maria, RS state, Brazil, along a year. The EO was extracted from fresh and dried leaves by hydrodistillation. When reproductive organs were observed, they were extracted in order to examine their influence on the yield of leaf EO. To determine the moisture content (MC%), 20 g of leaves and 10g of reproductive organs were dried separately in an oven at 50°C until constant weight. The yield of leaf EO (% w/ w) was calculated for the fresh material based on the dry weight considering the MC%, and for the dried material at room temperature. Only small seasonal variations in EO content was detected for the analyzed samples, with no statistical difference between them. The highest yield was observed in the spring for EO from the leaves (1.61 ± 0.09%), and from the reproductive organs (5.17%), while the lowest yields of leaf EO occurred in the summer (1.32 ± 0.14%), the only season which showed no presence of the reproductive organs. The absence of significant difference between the yields indicates no quantitative seasonal variability in production of EO in leaves of this population. However, yields did not differ statistically, indicating no seasonal variability of the EO content of the leaves of this population. Therefore, the collection of this plant organ can be performed at any time of the year in order to obtain this extractive. Since there was no decrease in the content of EO during the drying process at room temperature, this post-harvest processing can be adopted.Piper gaudichaudianum Kunth (Piperaceae) é uma planta com ampla distribuição no território brasileiro. Além de sua importância ecológica, é utilizada na medicina popular e muitas de suas atividades biológicas já foram comprovadas. O objetivo deste trabalho foi verificar o efeito da sazonalidade sobre o teor de óleo essencial (OE) em folhas de Piper gaudichaudianum e averiguar a possível influência do processo de secagem do material vegetal no rendimento deste extrativo. Foram coletadas aleatoriamente folhas de indivíduos de uma população nativa de Santa Maria - RS, Brasil, ao longo de um ano. O OE foi extraído de folhas frescas e secas à temperatura ambiente pelo método de hidrodestilação. Quando verificada a presença de órgãos reprodutivos, os mesmos foram extraídos, a fim de examinar a sua influência no rendimento do OE de folhas. Para determinação do teor de umidade (TU%), 20 g de folhas e 10 g de órgãos reprodutivos foram secos separadamente em estufa a 50°C até peso constante. O rendimento de OE de folhas (% m/m) foi calculado para o material fresco com base na massa seca, considerando o TU%, bem como para o material seco à temperatura ambiente. Apenas pequenas variações sazonais nos teores de OE foram detectadas para as amostras analisadas, não havendo diferença estatística entre eles. O maior rendimento foi observado na primavera, tanto para o OE de folhas (1,61±0,09%), quanto de órgãos reprodutivos (5,17%), enquanto o menor teor de OE em folhas ocorreu no verão (1,32±0,14%), a única estação em que não houve a presença de órgãos reprodutivos. A ausência de diferença significativa entre os rendimentos indica que não houve variabilidade sazonal quantitativa na produção de OE em folhas desta população. Portanto, a coleta deste órgão vegetal pode ser realizada em qualquer época do ano visando à obtenção deste extrativo. Uma vez que não foi verificada diminuição do teor de OE durante o processo de secagem à temperatura ambiente, esse processamento pós-colheita poderá ser adotado

    Arborização do campus da Universidade Federal de Santa Maria e conscientização da comunidade acadêmica

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    This work aimed to raise the academic community, at the Federal University of Santa Maria, regarding the importance of using appropriate tree species in public places. The tree density and species richness were evaluated. Conflicts were identified in afforestation and measures were proposed in order to solving it. The following data were collected: tree species, height (m), CAP (cm), presence or absence of overhead wires; list of examples of buildings with setback (m); existence of architectural elements, evaluation of the effect of the root system, and , presence or absence of adequate free area (1 m2). There was the presence of 1270 copies, distributed in 75 species, 60 genera and 32 botanical families. The most abundant species were Handroanthus chrysotrichus (Mart. ex DC) Mattos, Peltophorum dubium (Spreng.) Taub., Tipuana tipu (Benth.) Kuntze, Handroanthus heptaphyllus (Vell.) Mattos e Ligustrum japonicum Thunb. Through this work, conflicts related to the size of trees coupled with inadequate small free area, and the use of exotic species on native restriction, when used to add value to the landscape diversity, were observed. Environmental education is a fundamental technique of solving these problems, because it promotes the community awareness concerning the appropriate tree species and the correct way to do the planting in every situation.Este trabalho teve como objetivo a conscientização da comunidade acadêmica da Universidade Federal de Santa Maria, RS, no que se refere à importância da utilização de espécies arbóreas adequadas em espaços públicos. A densidade de árvores e a riqueza de espécies foram avaliadas. Foram identificados conflitos na arborização e propostas medidas para solucioná-los. Os seguintes dados foram levantados: espécie arbórea; altura (m), CAP (cm); existência ou não de fiação aérea; relação dos exemplares com recuo de edificações (m); existência de elementos arquitetônicos; avaliação do efeito do sistema radicular; e; presença ou ausência de área livre adequada (1 m2). Verificou-se a presença de 1270 exemplares, distribuídos em 75 espécies, 60 gêneros e 32 famílias botânicas. As espécies mais abundantes foram Handroanthus chrysotrichus, Peltophorum dubium, Tipuana tipu, Handroanthus heptaphyllus e Ligustrum japonicum. A partir deste trabalho, observaram-se conflitos em relação ao porte inadequado de árvores aliados à pequena dimensão de área livre, e a utilização de espécies exóticas em restrição de nativas, que quando utilizadas agregam valor de diversidade a paisagem. A educação ambiental técnica é fundamental na resolução destes problemas, pois promove a conscientização da comunidade a respeito das espécies arbóreas adequadas e da maneira correta de se realizar o plantio em cada situação

    COMPOSIÇÃO PAISAGÍSTICA E ARBORIZAÇÃO DO CAMPO DE INSTRUÇÃO DE SANTA MARIA

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    The Education Field of Santa Maria (CISM) is a private Army area, located in the district of SaintValentine and currently used for conducting military maneuvers and eventually serving as a placeto community visitation. At this place, there are fragments of native vegetation, as well asspecimens of this flowering composes the CISM surrounding landscape. This flora is preserved inpart due to lack of users awareness. This study aims to propose a planning and landscaping designwithin the precepts of environmental education techniques. According to the observations and evaluations, it was observed that the tropical garden composition is the most appropriated, sincethe most present species are used in these compositions. In this sense, the place was visited andthe photographic recording of the species, such as its correct identification and variables ofdendrometric interest surveys, were accomplished. Through environmental education techniques,it is possible to suggest a landscaping composition suitable for the existing species andarchitectural elementshttp://dx.doi.org/10.5902/223611703891O Campo de Instrução de Santa Maria (CISM) é uma área privada do Exército, localizada no Distrito de São Valentim e utilizada para realização de manobras militares e eventualmente servindo de local de visita à comunidade. Neste local, encontram-se fragmentos de vegetação nativa, assim como exemplares desta flora compõem a paisagem de entorno da sede do CISM. Essa flora encontra-se em parte preservada, devido à falta de conhecimento dos usuários. Este estudo tem como objetivo planejar e propor um projeto paisagístico dentro dos preceitos da educação ambiental técnica. De acordo com as observações e avaliações realizadas, observou-se que a composição de um Jardim Tropical é a mais adequada, visto que a maioria das espécies presentes são elementos utilizados nessas composições. Com este objetivo, foram realizadas visitas ao local, registro fotográfico das espécies, bem como sua correta identificação e levantamento de variáveis dendrométricas de interesse. Através da educação ambiental técnica, é possível sugerir uma composição paisagística adequada ao local e às espécies e elementos arquitetônicos já existentes

    Ultrafast Heat Flow in Heterostructures of Au Nanoclusters on Thin Films: Atomic Disorder Induced by Hot Electrons

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    We study the ultrafast structural dynamics, in response to electronic excitations, in heterostructures composed of size-selected Au nanoclusters on thin-film substrates with the use of femtosecond electron diffraction. Various forms of atomic motion, such as thermal vibrations, thermal expansion, and lattice disordering, manifest as distinct and quantifiable reciprocal-space observables. In photoexcited supported nanoclusters, thermal equilibration proceeds through intrinsic heat flow between their electrons and their lattice and extrinsic heat flow between the nanoclusters and their substrate. For an in-depth understanding of this process, we have extended the two-temperature model to the case of 0D/2D heterostructures and used it to describe energy flow among the various subsystems, to quantify interfacial coupling constants and to elucidate the role of the optical and thermal substrate properties. When lattice heating of Au nanoclusters is dominated by intrinsic heat flow, a reversible disordering of atomic positions occurs, which is absent when heat is injected as hot substrate phonons. The present analysis indicates that hot electrons can distort the lattice of nanoclusters, even if the lattice temperature is below the equilibrium threshold for surface premelting. Based on simple considerations, the effect is interpreted as activation of surface diffusion due to modifications of the potential energy surface at high electronic temperatures. We discuss the implications of such a process in structural changes during surface chemical reactions

    Formation of lipofuscin-like autofluorescent granules in the retinal pigment epithelium requires lysosome dysfunction

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    Funding Information: Supported by Funda??o para a Ciência e Tecnologia (FCT) ? Portugal co-funded by FEDER under the PT2020 Partnership Agreement (to MCS, including project PTDC/MED-PAT/30385/2017, iNOVA4Health-UIDB/04462/2020, research infrastructure PPBI-POCI-01-0145-FEDER-022122, M-ERA.NET 2/0005/2016), Boehringer Ingelheim (to MCS), Fight for Sight UK (to MCS), Wellcome Trust grant number 212216/Z/18/Z/ (to CEF). MJH was funded by Moor-fields Eye Charity with the Bill Brown 1989 Charitable Trust PhD studentship 538158, MLS was funded by FCT-CEECIND/01536/2018, ACF was funded by FCT PhD studentship (PD/BD/135503/2018). This work was developed with the support from the research infrastructure PPBI-POCI-01-0145-FEDER-022122, co-financed by FCT (Portugal) and Lisboa2020, under the PORTUGAL2020 agreement (European Regional Development Fund) and this article is supported by the LYSOCIL project funded by the European Union?s Horizon 2020 programme under grant agreement No. 811087. Funding Information: Supported by Fundação para a Ciência e Tecnologia (FCT) – Portugal co-funded by FEDER under the PT2020 Partnership Agreement (to MCS, including project PTDC/MED-PAT/30385/2017, iNOVA4Health-UIDB/04462/2020, research infrastructure PPBI-POCI-01-0145-FEDER-022122, M-ERA.NET 2/0005/2016), Boehringer Ingelheim (to MCS), Fight for Sight UK (to MCS), Wellcome Trust grant number 212216/Z/18/Z/ (to CEF). MJH was funded by Moor-fields Eye Charity with the Bill Brown 1989 Charitable Trust PhD studentship 538158, MLS was funded by FCT-CEECIND/01536/2018, ACF was funded by FCT PhD studentship (PD/BD/135503/2018). This work was developed with the support from the research infrastructure PPBI-POCI-01-0145-FEDER-022122, co-financed by FCT (Portugal) and Lisboa2020, under the PORTUGAL2020 agreement (European Regional Development Fund) and this article is supported by the LYSOCIL project funded by the European Union’s Horizon 2020 programme under grant agreement No. 811087. Publisher Copyright: Copyright 2021 The AuthorsPURPOSE. We aim to characterize the pathways required for autofluorescent granule (AFG) formation by RPE cells using cultured monolayers. METHODS. We fed RPE monolayers in culture with a single pulse of photoreceptor outer segments (POS). After 24 hours the cells started accumulating AFGs that were comparable to lipofuscin in vivo. Using this model, we used a variety of light and electron microscopical techniques, flow cytometry and Western blot to analyze the formation of AFGs. We also generated a mutant RPE line lacking cathepsin D by gene editing. RESULTS. AFGs seem to derive from incompletely digested POS-containing phagosomes and after 3 days are surrounded by a single membrane positive for lysosome markers. We show by various methods that lysosome-phagosome fusion is required for AFG formation, and that impairment of lysosomal pH or catalytic activity, particularly cathepsin D activity, enhances AF accumulation. CONCLUSIONS. We conclude that lysosomal dysfunction results in incomplete POS degradation and enhanced AFG accumulation.publishersversionpublishe

    Artistas sobre outras obras

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    Refletindo sobre a arte enfenta-se coisa difícil, e não raro temos de encarar o regresso à partida: é coisa antiga, ligação funda ao que diferencia o humano, assentando na arbitrariedade da sua cultura e na sua transmissão sígnica. A pergunta, na busca dos grandes signos, é quase simples: o que há de novo? Poderia dizer-se que a esta pergunta respondem, cada um a seu modo, os 16 artistas, agora autores, desafiados pela convocatória desta revista: no Estúdio se faz a Estúdio.info:eu-repo/semantics/publishedVersio
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