4,362 research outputs found

    Using presence-absence data to establish reserve selection procedures that are robust to temporal species turnover

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    Previous studies suggest that a network of nature reserves with maximum efficiency (obtained by selecting the minimum area such that each species is represented once) is likely to be insufficient to maintain species in the network over time. Here, we test the performance of three selection strategies which require presence-absence data, two of them previously proposed (multiple representations and selecting an increasing percentage of each species' range) and a novel one based on selecting the site where each species has exhibited a higher permanence rate in the past. Multiple representations appear to be a safer strategy than selecting a percentage of range because the former gives priority to rarer species while the latter favours the most widespread. The most effective strategy was the one based on the permanence rate, indicating that the robustness of reserve networks can be improved by adopting reserve selection procedures that integrate information about the relative value of sites. This strategy was also very efficient, suggesting that the investment made in the monitoring schemes may be compensated for by a lower cost in reserve acquisition

    Contribuições da gestão de recursos humanos para a criatividade e inovação organizacional

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    Inovar é, hoje, um imperativo para as organizações. Desse modo, é importante promover a criatividade dos colaboradores e apoiar o processo que a transforma em inovação. O objetivo desta pesquisa foi compreender como a Gestão de Recursos Humanos (GRH) pode promover um ambiente de trabalho propício à criatividade, na perspectiva dos colaboradores. Para isso, realizou-se um estudo de caso exploratório em uma empresa portuguesa de médio porte da área das Tecnologias de Informação (TI). Recorreu-se a diferentes fontes de análise, como observação participante, documentos organizacionais e entrevistas. Os dados resultantes dessas fontes foram analisados e organizados com ajuda da template analysis. Os resultados revelaram que, para as chefias e colaborador entrevistados, a criatividade na organização pode ser promovida por meio da existência de suporte para as novas ideias, tolerância ao erro, autonomia, liberdade para que os colaboradores exerçam suas funções e debates para a partilha de ideias. A GRH pode criar condições, por meio das suas práticas (p. ex., formação, avaliação de desempenho, recrutamento e seleção), para a promoção da criatividade e inovação organizacional.Innovation is a key factor to organizations’ competitiveness. To achieve that, it is important to promote creativity among employees and support the transformational process from creativity to innovation. The main objective of this research was to understand how Human Resource Management (HRM) can promote a work environment favorable to creativity, from the perspective of the employees. A case study was carried out on a medium-sized Portuguese information technology (IT) enterprise. Various research techniques were used to collect data, including observation, document analysis, and interviews. Data were organized and analyzed using a template analysis. The results revealed that, for the respondents (managers and employee), creativity within the organization can be promoted by the existence of support for new ideas, error tolerance, autonomy, freedom for employees to perform their tasks, and discussions to share ideas. HRM can create conditions, through their practices (e.g., training, performance evaluation, recruitment, and selection), to promote organizational creativity and innovation

    Synthesis of novel psoralen analogues and their anti-proliferative effect on human cancer cell lines

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    We describe the synthesis of 3H-benzofuro[3,2-f]chromen-3-ones. The anti-proliferative effect on human cancer cell lines (MDA-MB231 and HeLa) was evaluated.FCT and FEDER, for National NMR Networ

    Cellulase stability, adsorption/desorption profiles and recycling during successive cycles of hydrolysis and fermentation of wheat straw

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    The potential of enzymes recycling after hydrolysis and fermentation of wheat straw under a variety of conditions was investigated, monitoring the activity of the enzymes in the solid and liquid fractions, using low molecular weight substrates. A significant amount of active enzymes could be recovered by recycling the liquid phase. In the early stage of the process, enzyme adsorb to the substrate, then gradually returning to the solution as the saccharification proceeds. At 50 °C, normally regarded as an acceptable operational temperature for saccharification, the enzymes (Celluclast) significantly undergo thermal deactivation. The hydrolysis yield and enzyme recycling efficiency in consecutive recycling rounds can be increased by using high enzyme loadings and moderate temperatures. Indeed, the amount of enzymes in the liquid phase increased with its thermostability and hydrolytic efficiency. This study contributes towards developing effective enzymes recycling strategies and helping to reduce the enzyme costs on bioethanol production.The authors acknowledge funding through FP7 KACELLE (Kalundborg Cellulosic Ethanol) project for supporting this work. We also thank Dra. Lucilia Domingues for supplying the yeast Saccharomyces cerevisiae CEN PK 113 wild type

    3-Aminopyrroles and their application in the synthesis ofpyrrolo[3,2-d]pyrimidine (9-deazapurine) derivatives

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    3-Aminopyrrole derivatives have been synthesized from 3-anilino-2-cyanoacrylonitrile using Thorpe-Ziegler cyclization. These substituted pyrroles are readily converted into 5H-pyrrolo[3,2- d]pyrimidine (9-deazapurines).FEDERFundação para a Ciência e Tecnologia (FCT

    Synthesis and characterization of psoralen analogues based on carbazoles

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    Novel psoralen analogues based on carbazoles were synthesized and characterized.Fundação para a Ciência e Tecnologia (FCT) and FEDER, for National NMR Networ

    Heterocyclic synthesis with nitriles: synthesis of pyridazine and pyridopyridazine derivatives

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    The reaction of MND with aryldiazonium chlorides followed by cyclization afforded the pyridazinimine derivatives. Reaction of the latter with another mole of malononitrile produce only pyrido[3,2-c]pyridazine derivatives. Reaction of 4-aminopyridazinone-3- carboxylic acid esters with malononitrile gave only pyridazine-3-carboxylic acid.Fundação para a Ciência e a Tecnologia (FCT) - POCTI-SFA-3-686, SFRH/BPD/31490/2006Fundo Europeu de Desenvolvimento Regional (FEDER

    Synthesis of novel benzofurocoumarin analogues and their anti-proliferative effect on human cancer cell lines

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    The synthesis of five new tetracyclic benzofurocoumarin (benzopsoralen) analogues is described. Their inhibitory effects on the growth of three human tumour cell lines (MDA MB 231 (breast adenocarcinoma), HeLa (cervix adenocarcinoma) and TCC-SUP (bladder transitional cell carcinoma)) were evaluated, and discussed in terms of structure–activity relationship.FCT and FEDER, for National NMR Network (Bruker Avance II 400), REEQ/630/QUI/2005 (LC/MS instrument) and the PhD grant (SFRH/BD/48636/2008)

    Synthesis of novel psoralen analogues and in vitro antitumor activity

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    Psoralens are natural products present in several plant families that are extremely toxic to a wide variety of prokaryotic and eukaryotic organisms. They are potentially active in diseases such as vitiligo, psoriasis, and several types of cancer. Following our interest on this type of compounds 1 four new psoralen analogues were prepared, 1a-1c and 1e. To synthesize 1a (R = H) the method of Harayama and Ishii was used where the cinnamate was obtained by the Wittig reaction followed by ring closure. Condensation of 1-formyl-2-hydroxycarbazole with diethyl malonate gave 1b which by basic hydrolysis yielded compound 1c. Compound 1d was prepared before.2 Condensation of the 2-hydroxycarbazole with ethyl acetoacetate gave 1e. The products were characterized by elemental analysis, 1H and 13C NMR. Moreover, the anti-proliferative effect of compounds 1a-1e on human cancer cell lines (MDA-MB 231, HeLa and TCCSUP) was evaluated. Results suggest that these psoralen analogues possess a potent cytotoxic effect against the cell lines studied. Computational and molecular docking studies are being carried out.Fundação para a Ciência e a Tecnologia (FCT)(PEst-C/QUI/UI0686/2011), FEDER-COMPET
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