2,970 research outputs found

    Reflexão sobre uma experiência pedagógica interdisciplinar no ensino do desenho num curso de design

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    A função do desenho na metodologia projectual do designer tem merecido o interesse de vários autores. Nessas abordagens, está presente a afirmação de que o desenho é essencial no processo de investigação do design para o registo de diversas variantes e de várias soluções ao longo da metodologia projectual (Cross, 2007). As profundas alterações da natureza do Design provocadas pelo contexto histórico actual (Norman, 2011) justificam a pertinência de uma reflexão alargada em torno do papel do desenho nos cursos de design, adaptado a esta nova realidade. Este é um desafio colocado hoje às instituições de ensino e seus intervenientes, na organização de estruturas curriculares e métodos pedagógicos. Conceitos como colaboração ou design multidisciplinar, entre outros, têm sido debatidos como estratégias para o ensino do design (Heller and Talarico, 2011, pp. 82-85). Neste contexto, e enquanto docentes nas áreas do Desenho e do Design, importa-nos abordar as seguintes questões: - de que forma é possível enquadrar métodos do desenho ao ensino do design actual? - de que forma poderá o Desenho ser pensado enquanto prática interdisciplinar? - que contributos podem essas práticas trazer para o processo de ensino/aprendizagem? Com base nestas preocupações, desenvolveu-se um projecto interdisciplinar entre as unidades curriculares de Desenho e de Estética e Teoria do Design no Curso de Design Gráfico, na Instituição onde leccionamos. Neste artigo, apresentaremos os objectivos e o processo desenvolvido, assim como a análise e conclusões desta experiência pedagógica

    Quasinormal modes of asymptotically flat rotating black holes

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    We study the main properties of general linear perturbations of rotating black holes in asymptotically flat higher-dimensional spacetimes. In particular, we determine the quasinormal mode (QNM) spectrum of singly spinning and equal angular momenta Myers-Perry black holes (MP BHs). Emphasis is also given to the timescale of the ultraspinning and bar-mode instabilities in these two families of MP BHs. For the bar-mode instabilities in the singly spinning MP BH, we find excellent agreement with our linear analysis and the non-linear time evolution of Shibata and Yoshino for d=6,7 spacetime dimensions. We find that d=5 singly spinning BHs are linearly stable. In the context of studying general relativity in the large dimension limit, we obtain the QNM spectrum of Schwarzschild BHs and rotating MP BHs for large dimensions. We identify two classes of modes. For large dimensions, we find that in the limit of zero rotation, unstable modes of the MP BHs connect to a class of Schwarzschild QNMs that saturate to finite values.Comment: 52 pages. 25 figure

    High-glucose feeding of gilthead seabream (Sparus aurata) larvae: effects on molecular and metabolic pathways

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    Nutritional programming has begun to arouse interest as a novel tool to alter specific metabolic pathways or functions in farmed animals. The aim of the present study was to explore the potential of early glucose stimuli to induce changes in nutrient metabolism of gilthead seabream. Nutritional conditioning was performed by delivering glucose-rich feed at three distinct recurrent periods of larval feeding regime: during first-feeding with rotifers (3 days after hatching, DAH) and mid-feeding with Artemia metanauplii (20DAH) and the beginning of inert diet feeding (30DAH), called the Recurrent treatment (REC). As opposed, the control treatment (CTRL) did not experience any glucose stimuli. At post-larval stage (from 50 to 60DAH), both treatments were challenged with a high-carbohydrate diet (50%). The immediate response to the early stimuli was assessed through gene expression of metabolic markers and by nutrient metabolism using [C-14] tracers. Each dietary stimulus induced metabolic changes on REC larvae, shown by altered expression of some genes, including those involved in glycolysis, and by a different pattern of glucose utilization. However, none of the molecular adaptations (except G6PDH gene) were persistent in the viscera and muscle of challenged post-larvae from REC group. In contrast, the glucose metabolism of challenged REC post-larvae revealed a shift towards a higher catabolism and lower glucose retention in tissues, compared to the CTRL group, suggesting an improvement of glucose oxidation pathways. In addition, the REC group showed a higher bio-conversion of glucose into lipids, indicating enhanced hepatic lipogenesis. The early stimuli did not affect the relative retention or use of amino acids or the growth and survival of challenged fish, up to 60DAH. In summary, although not substantiated at a molecular level, our data reveal that a recurrent high-glucose stimulus during larval stages affects the short-term modulation of pathways for glucose utilization in gilthead seabream. (C) 2015 Elsevier B.V. All rights reserved

    One hand or two hands? 2D selection tasks with the leap motion device

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    In this paper, we present the results from an experiment designed to compare two selection gestures (hand grab and screen tap) for the Leap Motion controller in 2D pointing tasks. We used the ISO 9241-9 multi-directional tapping test for comparing the devices, and we analyze the results using standard throughput and error rate measures as well as additional accuracy measures. We also present the results from the ISO 9241-9 assessment of comfort questionnaire. To complement this analysis, the computer mouse was also evaluated in order to serve as a comparison. Results indicate that the hand grab gesture performs better than the screen tap

    The Leap Motion Movement for 2D Pointing Tasks: Characterisation and Comparison to Other Devices

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    In this paper we present the results from an experiment designed to characterize the Leap Motion movement in 2D pointing tasks and compare it to a mouse and touchpad. We used the ISO 9241-9 multi-directional tapping test for comparing the devices, and we analyse the results using standard throughput and error rate measures as well as additional accuracy measures such as target re-entry, task axis crossing, movement direction change, orthogonal direction change, movement variability, movement offset, and movement error. We also present the results from the ISO9241-9 assessment of comfort questionnaire, and our observations from the participant’s postures when using the Leap Motion device. Results indicate that the Leap Motion performs poorly in these tasks when compared to a mouse or touchpad

    Reforço à flexão com compósitos de CFRP de vigas de madeira lamelada-colada

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    Neste trabalho apresenta-se uma campanha de ensaios em vigas de madeira lamelada-colada reforçadas à flexão com dois sistemas de compósitos unidireccionais de CFRP (polímeros reforçados com fibras de carbono), o curado “in situ” (manta) e o pré-fabricado (laminado). Para cada sistema de CFRP, o reforço foi aplicado externamente ou internamente na face inferior da penúltima lamela. No caso do reforço interno foi, também, avaliada a influência da colagem do CFRP numa pequena cavidade previamente executada na face da lamela a reforçar. Os resultados obtidos são analisados e interpretados, referindo-se as principais conclusões, tendo em vista avaliar a viabilidade do reforço à flexão de vigas de madeira lamelada-colada através da colagem de compósitos de CFRP.Flexilam. BeTTor MBT Portugal

    Compósitos de CFRP unidireccionais no reforço de vigas de madeira lamelada-colada

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    Neste trabalho apresenta-se a campanha de ensaios realizada para avaliar a eficiência da aplicação de dois sistemas compósitos de CFRP no reforço à flexão de vigas de madeira lamelada-colada: o curado “in situ” (manta) e o pré-fabricado (laminado). Cada um dos sistemas de CFRP foi aplicado quer em reforço externo (colagem na face traccionada da viga) quer em reforço interno (colagem na face inferior da penúltima lamela). No caso do reforço interno foi, ainda, avaliada a influência da colagem do CFRP numa cavidade previamente executada na face da lamela a reforçar. Numa fase precedente, avaliou-se a aderência madeira- CFRP por intermédio de ensaios de “pull-off”, tendo-se analisado as seguintes variáveis: o tipo de cola, a utilização de primário e o tratamento da superfície.Flexilam.BeTTor MBT Portugal

    Polymerization of ethylene using metallocene and aluminoxane systems

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    This paper describes ethylene polymerization using a number of metal-locene and aluminoxane catalyst systems, Cp2MR2 and methylaluminoxane [M = Zr, W, Nb; R = Cl, CH3]. Two types of methylaluminoxane, MAO (1) and MAO (2), were used as cocatalysts. The polymerization activities of the complexes Cp2WCl2 and Cp2NbCl2 were compared with that of Cp2ZrCl2. The Nb and W complexes were found to be less active than the Zr complex. Polyethylene characterization was also carried out by the following methods: gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR).info:eu-repo/semantics/publishedVersio

    Holographic dual of hot Polchinski-Strassler quark-gluon plasma

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    Abstract: We construct the supergravity dual of the hot quark-gluon plasma in the mass-deformed N = 4 Super-Yang-Mills theory (also known as N = 1∗). The full ten-dimensional type IIB holographic dual is described by 20 functions of two variables, which we determine numerically, and it contains a black hole with S5 horizon topology. As we lower the temperature to around half of the mass of the chiral multiplets, we find evidence for (most likely a first-order) phase transition, which could lead either to one of the Polchinski-Strassler confining, screening, or oblique vacua with polarized branes, or to an intermediate phase corresponding to blackened polarized branes with an S2 ×S3 horizon topology. This phase transition is a feature that could in principle be seen by putting the theory on the lattice, and thus our result for the ratio of the chiral multiplet mass to the phase transition temperature, mc/T = 2.15467491205(6), constitutes the first prediction of string theory and AdS/CFT that could be independently checked via four-dimensional super-QCD lattice computation. We also construct the black-hole solution in certain five-dimensional gauged supergravity truncations and, without directly using uplift/reduction formulae, we find strong evidence that the five- and ten-dimensional solutions are the same. This indicates that five-dimensional gauged supergravity is powerful enough to capture the physics of the high-temperature deconfined phase of the Polchinski-Strassler quark-gluon plasma
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