2,296 research outputs found

    Cryopreservation of Byrsonima intermedia embryos followed by room temperature thawing

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    Byrsonima intermedia is a shrub from the Brazilian Cerrado with medicinal properties. The storage of biological material at ultra-low temperatures (-196°C) is termed cryopreservation and represents a promising technique for preserving plant diversity. Thawing is a crucial step that follows cryopreservation. The aim of this work was to cryopreserve B. intermedia zygotic embryos and subsequently thaw them at room temperature in a solution rich in sucrose. The embryos were decontaminated and desiccated in a laminar airflow hood for 0-4 hours prior to plunging into liquid nitrogen. The embryo moisture content (% MC) during dehydration was assessed. Cryopreserved embryos were thawed in a solution rich in sucrose at room temperature, inoculated in a germination medium and maintained in a growth chamber. After 30 days, the embryo germination was evaluated. No significant differences were observed between the different embryo dehydration times, where they were dehydrated for at least one hour. Embryos with a MC between 34.3 and 20.3% were germinated after cryopreservation. In the absence of dehydration, all embryos died following cryopreservation. We conclude that B. intermedia zygotic embryos can be successfully cryopreserved and thawed at room temperature after at least one hour of dehydration in a laminar airflow bench

    Collective participation at the service of cultural heritage: user-generated content in Portuguese memory institutions

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    The 2030 Agenda, set at the 2015 UN Summit, sets out the Sustainable Development Goals covering economic, cultural, environmental and social development. These goals set out a plan for all countries to actively engage in making the world better. These are a set of 17 objectives that have a universal ambition, are integrated and indivisible and require a global partnership between public and private institutions, governments and civil society. Sustainable development is a fundamental and overarching goal on which people are based and their ability to aggregate into common and community goals. Around the heritage, regarding GLAM institutions, calls for the intervention of the people of the community in the virtual platforms, with the help of Web 2.0 that introduced new ways of relationship between the information services and their users (real and potential), paving the way for user-generated content. At the same time, the emergence and development of the citizen science movement has consolidated this trend of openness, availability of collections and unmediated liaison with citizens (users and non-users), contributing to the evolution of new ways of conceiving the representation of information. This trend is visible all over the GLAM sector, especially in the West, on various platforms (wikis, blogs, Flickr, websites, etc.) with very interesting results. The aim of this paper is to identify and map these trends in Portugal and to verify if they are (or not) in line with their foreign counterparts. It is concluded by the still incipient but growing trend in Portugal, which can be partly explained by the fact that the coordinating services of the GLAM areas do not take position or develop projects within the web 2.0

    As cores e a sua influência no processo projetual

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    Nos dias atuais, a tecnologia em materiais e compostos viabiliza a aplicação de uma grande gama de cores em qualquer processo de produção seja este gráfico ou produto. Antigamente, as limitações da produção em série permitiam uma pequena variedade de cores e motivos, e o consumidor tinha acesso a poucas opções na hora da compra. Hoje, as empresas fazem uso incessante das cores em produtos, a fim de os diferenciar dos concorrentes, o que desperta um alerta durante o processo criativo dos designer: Como aplicar adequadamente as cores aos produtos? Este artigo objetiva auxiliar estes profissionais a entenderem como funciona o espectro cromático na sua fisiologia e psicologia, de maneira a demonstrar um método de criar uma paleta de cores direcionada para o usuário que se pretende atingir. Essa sugestão métodologica, entre outras possíveis, deve facilitar o processo de escolha das cores pelo profissional durante o processo criativo e projetua

    Identidade visual e sua relação com a linguagem não verbal

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    A identidade visual assenta numa relação semântica de diversos signos que integram um sistema coerente. Uma linguagem bimédia de texto e imagem que se complementam de modo a criar uma mensagem compreensível. Este estudo visa o uso da linguagem não verbal no âmbito do projeto de identidade visual corporativa, contextualizando o papel do designer informacional enquanto mediador da mensagem corporativa para os seus públicos

    On the equivalence of the self-dual and Maxwell-Chern-Simons models coupled to Fermions

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    We study the exact equivalence between the self-dual model minimally coupled with a Dirac field and the Maxwell-Chern-Simons model with non-minimal magnetic coupling to fermions. We show that the fermion sectors of the models are equivalent only if a Thirring like interaction is included. Using functional methods we verify that, up to renormalizations, the equivalence persists at the quantum level.Comment: 8 pages, revte

    Anomalous diffusion and anisotropic nonlinear Fokker-Planck equation

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    We analyse a bidimensional nonlinear Fokker-Planck equation by considering an anisotropic case, whose diffusion coefficients are DxxθD_x \propto |x|^{-\theta} and DyyγD_y \propto |y|^{-\gamma} with θ,γR\theta, \gamma \in {\cal{R}}. In this context, we also investigate two situations with the drift force F(r,t)=(kxx,kyy)\vec{F}(\vec{r},t)=(-k_{x}x, -k_y y). The first one is characterized by kx/ky=(2+γ)/(2+θ)k_x/k_y=(2+\gamma)/(2+\theta) and the second is given by kx=kk_{x}=k and ky=0k_{y}=0. In these cases, we can verify an anomalous behavior induced in different directions by the drift force applied. The found results are exact and exhibit, in terms of the qq-exponentials, functions which emerge from the Tsallis formalism. The generalization for the DD-dimensional case is discussed.Comment: 6 pages, tex fil

    Preparation of hybrid organic-inorganic materials based on a di-ureasil matrix doped with lithium bis(trifluoromethanesulfonyl)imide

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    In this presentation we describe the preparation of solvent-free solid polymer electrolytes (SPEs) by the sol-gel route with the incorporation of controlled quantities of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) into the host matrix. The host framework of these xerogels, designated as di-ureasils and represented by d-U(900), contains oxyethylene oligomers with about 15 repeat units bonded at each end to a siliceous backbone through urea bridging links. Electrolytes were characterized by ionic conductivity measurements, cyclic voltammetry at a gold microelectrode and thermal analysis. The results obtained reveal that these hybrid materials are completely amorphous and exhibit appropriate electrochemical characteristics for a variety of applications.Fundação para a Ciência e a Tecnologia - POCI/QUI/59856/2004; POCTI/3/686; SFRH/BD/22707/2005

    Analytical strategies for determination of cadmium in Brazilian vinegar samples using ET AAS

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    AbstractThis paper proposes two methods for determination of cadmium in vinegar employing electrothermal atomic absorption spectrometry. The optimization step was performed using two-level full factorial and Box–Behnken designs, being that a new multiple response function was established. Under experimental conditions of pyrolysis temperature of 640°C and atomization temperature of 2000°C, the direct method allows the analysis using the external calibration technique, with limit of quantification of 14ngL−1 and characteristic mass of 1.2pg, having aluminium as chemical modifier. This method was applied in six samples of vinegar acquired from Salvador City, Brazil. The cadmium content varied from 20 to 890ngL−1. Other method was also proposed by digestion using nitric acid and hydrogen peroxide in reflux system employing cold finger, being cadmium determined by ETAAS. The results obtained with the complete digestion procedure were in agreement with those found by the direct method proposed herein

    Plano de Acção - Castelo Branco Agenda XXI

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    Considerando que é importante mobilizar os agentes locais para um caminho que deve ser comum, formataram-se vários momentos de reunião e discussão para, em conjunto, verter para "Castelo Branco Agenda XXI" um Plano de Acção com medidas que unam e co-responsabilizem todas as entidades neste processo de crescimento, sob o padrão inovador que o caráter prático e planeado de uma Agenda Local impõe. As reuniões sectoriais e de proximidade que foram promovidas e o período de consulta do Diagnóstico para a Sustentabilidade do concelho, possibilitaram identificar os caminhos da Sustentabilidade de Castelo Branco, que são apresentados neste relatório.info:eu-repo/semantics/publishedVersio

    In vitro culture of Annona emarginata: a rootstock for commercial annonaceae species

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    Annona emarginata is a native fruit tree in the Brazilian Cerrado which, unlike the commercial species, does not present a high fruit quality. On the other hand, it stands out based on its rootstock value. However, there are some problems that hinder the largescale production of Annona emarginata seedlings for use as a rootstock. In order to overcome these difficulties, micropropagation has become a viable alternative for the rapid and efficient propagation of Annona spp, but Annona emarginata micropropagation has not yet been reported. Therefore, the aim of this study was to initiate Annona emarginata in vitro growth. For axillary shoot proliferation, in vitro nodal segments of 0.5 cm were transferred to MS or WPM supplemented with BA at different concentrations. Nodal segments were also cultured on WPM medium with ranging concentrations of different plant growth regulators, aiming for either shoot elongation or rooting. The results showed that the use of 1 µM BA in WPM medium is recommended for in vitro multiplication of Annona emarginata. This is based on the low adventitious shoot formation, combined with a higher number of buds and leaves. The use of GA3 at any concentration tested induced the formation of malformed plants. Root formation could not be stimulated, regardless the duration of auxin treatment
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