220 research outputs found

    A viticultura das Arribas do Douro Internacional – uma história para contar, um futuro a reflectir

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    A actual Denominação de Origem (DO) Trás-os-Montes, sub-região Planalto Mirandês (PM) (Diário da República, 1ª série - Nº 216 – 9 de Novembro de 2006), situa-se no Nordeste de Portugal, distrito de Bragança, região natural Miranda- Mogadouro (Taborda, 1932). Inicialmente designada Ribadouro (1986) e posteriormente por Indicação de Proveniência Regulamentada do Planalto Mirandês (Decreto-Lei 341/89), a actual designação de sub-região Planalto Mirandês deve-se ao facto de grande parte da sua área estar incluída no conjunto dos planaltos de Miranda e de Mogadouro. Apesar de ser uma região relativamente pequena em termos de área de vinha (cerca de 4000 hectares), apresenta significativa diversidade mesoclimática, devida à fisiografia e hidrografia que determinam diversas exposições e declives e igualmente diversidade pedológica, em função dos materiais originários. Com efeito,é possível registar neste território diferentes origens e constituições, as quais se reflectem particularmente pela diversidade dos ecossistemas de vegetação natural: “O revestimento vegetal traz impressa a marca desta dupla natureza” (Taborda 1932)

    Poly(vinylidene fluoride) and copolymers as porous membranes for tissue engineering applications

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    Poly(vinylidene fluoride) (PVDF) and its main copolymers - poly(vinylidene fluoride-co-hexafluoropropene), P(VDF-HFP), and poly(vinylidene fluoride-co-trifluoroethylene), P(VDF-TrFE) - were processed by solvent casting at room temperature in the form of porous membranes. Copolymer membranes showed higher degree of porosity than PVDF, the average pore size being larger for P(VDF-TrFE) than for P(VDF-HFP) and PVDF. All membranes show high hydrophobicity with water contact angles in the range 94° to 115°, and electroactive beta phase contents above 90%. The adhesion and proliferation of both C2C12 myoblast and MC3T3-E1 pre-osteoblast cells on the membranes were investigated. It is demonstrated that PVDF membranes promote higher cell proliferation while P(VDF-HFP) membranes show the lowest proliferation for both kinds of cell. The proliferation on P(VDF-TrFE) membranes is cell dependent, higher for MC3T3-E1 cells but lower for C2C12 cells, related to the effect of the highly porous structure on the preferred morphology of each cell type, as the higher pore size and porosity of the P(VDF-TrFE) membrane induce cell elongation, which is preferred just by the C2C12 muscle cells.Funded by FEDER funds through the “Programa Operacional Fatores de Competitividade e COMPETE” and by national funds arranged by FCT Fundação para a Ciência e a Tecnologia, project references PTDC/CTM-NAN/112574/2009 and PEST-C/FIS/UI607/2014. Funding from “MateproOptimizing Materials and Processes”, ref. NORTE-07-0124-FEDER-000037”, co-funded by the “Programa Operacional Regional do Norte” (ON.2 e O Novo Norte), under the “Quadro de Referência Estrategico Nacional” (QREN), through the “Fundo Europeu de Desenvolvimento Regional” (FEDER). FCT for the SFRH/BPD/90870/2012 grant

    Impact of a Tutored Theoretical-Practical Training to Develop Undergraduate Students’ Skills for the Detection of Caries Lesions: Study Protocol for a Multicenter Controlled Randomized Study

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    Background: Tutored laboratorial activities could be a manner of improving the competency development of students. However, its impact over conventional theoretical classes has not yet been tested. Additionally, different university contexts could influence this issue and should be explored. Objective: To assess the impact of a tutored theoretical-practical training for teaching undergraduate students to detect caries lesions as compared with theoretical teaching activities. The impact of these teaching/learning activities will be assessed in terms of efficacy, cost/benefit, retention of knowledge/acquired competences, and student acceptability. Methods: Sixteen centers (7 centers from Brazil and 9 centers from other countries throughout the world) are involved in the inclusion of subjects for this protocol. A randomized controlled study with parallel groups will be conducted. One group (control) will be exposed to a 60- to 90-minute conventional theoretical class and the other group (test) will be exposed to the same theoretical class and also a 90-minute laboratory class, including exercises and discussions based on the evaluation of a pool of images and extracted teeth. The mentioned outcomes will be evaluated immediately after the teaching activities and also in medium- and long-term analyses. To compare the long-term outcomes, students who enrolled in the university before the participating students will be interviewed for data collection and these data will be used as a control and compared with the trained group. This stage will be a nonrandomized phase of this study, nested in the main study. Appropriate statistical analysis will be performed according to the aims of this study. Variables related to the centers will also be analyzed and used to model adjustment as possible sources of variability among results. Results: This ongoing study is funded by a Brazilian national funding agency (CNPq- 400736/2014-4). We expect that the tutored theoretical-practical training will improve the undergraduate students’ performance in the detection of caries lesions and subsequent treatment decisions, mainly in terms of long-term retention of knowledge. Our hypothesis is that tutored theoretical-practical training is a more cost-effective option for teaching undergraduate students to detect caries lesions. Conclusions: If our hypothesis is confirmed, the use of laboratory training in conjunction with theoretical classes could be used as an educational strategy in Cariology to improve the development of undergraduate students’ skills in the detection of caries lesions and clinical decision-making

    Avaliação da embebição e do desenvolvimento inicial das estruturas embrionárias de sementes de milho submetidas a diferentes potenciais hídricos

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    Substrates with water potentials between O and -12atm, were used to evaluate the behavior of corn seeds during the germination process. Water deficiency treatments were compared with the control (adequate available water) using seeds with and without fungicide treatment. The analysis and the interpretation of the results permitted to conclude that the absorption of water, the emergency and the initial development of the embryonic structures are interdependent and vary with the water deficit. For these cases the reduction of water potential promotes difficulties in the evolution of the processes. The presence of fungicide treatment may not influence quantitatively the processes occurring in the beginning of the germination.Empregando substratos com potenciais hídricos variáveis entre 0 e -12atm, o presente trabalho objetivou avaliar o comportamento das sementes de milho postas a germinar. As situações de deficiência hídrica foram diretamente comparadas à testemunha (plena disponibilidade de água), usando sementes com e sem tratamento fungicida. A análise e a interpretação dos resultados permitiram concluir que a absorção de água, a emergência e o desenvolvimento inicial das estruturas embrionárias são interdependentes e reagem no mesmo sentido ao déficit hídrico; para esses casos, a redução do potencial hídrico promove dificuldades na evolução dos processos. Paralelamente, a presença de tratamento fungicida pode não influenciar, quantitativamente, os fenômenos envolvidos no início da germinação
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