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- Differences in swimming force metrics induced by genderPublication . Amaro, Nuno; Morouço, Pedro; Marinho, Daniel A.
- Relationship of force metrics with swimming performance in age-group swimmersPublication . Amaro, Nuno; Morouço, Pedro; Marinho, Daniel A.
- O declínio de uma empresa brasileira de grande porte: o caso GradientePublication . Torres, Alexandre Pavan; Serra, Fernando Antonio; Almeida, Martinho Ribeiro; Ferreira, Manuel PortugalO trabalho apresenta o declínio organizacional da Gradiente. Este caso relevante foi estudado ao longo de 30 anos, utilizando dados e informações disponíveis, com o uso do software Atlas. ti. Foram examinados 1472 documentos. Utilizou-se de metodologia de estudo de caso para apresentação de uma teoria substantiva da Gradiente. Os resultados apontam para o impacto de cinco fatores: (1) a inércia em um ambiente em mudança, (2) a carência de recursos organizacionais e a menor capacidade de absorver choques, (3) erros na tomada de decisões, (4) os mecanismos de proteção governamental e a relação com o nível de competição, e (5) os recursos detidos pela empresa para fazer face à competição. A principal limitação é o método, por se tratar de estudo de caso único. Apesar da importância são poucas as pesquisas sobre o tema. Este estudo contribui para uma melhor compreensão do processo de declínio pelo estudo longitudinal ao longo de um grande período de tempo. Embora se tratando de um caso único, parece representar o ocorrido com uma grande quantidade de empresas brasileiras na década de 1990.
- Complexity control of HEVC through quadtree depth estimationPublication . Correa, Guilherme; Assunção, Pedro; Agostini, Luciano; Cruz, Luis A. da SilvaThe emerging HEVC standard introduces a number of tools which increase compression efficiency in comparison to its predecessors at the cost of greater computational complexity. This paper proposes a complexity control method for HEVC encoders based on dynamic adjustment of the newly proposed coding tree structures. The method improves a previous solution by adopting a strategy that takes into consideration both spatial and temporal correlation in order to decide the maximum coding tree depth allowed for each coding tree block. Complexity control capability is increased in comparison to a previous work, while compression losses are decreased by 70%. Experimental results show that the encoder computational complexity can be downscaled to 60% with an average bit rate increase around 1.3% and a PSNR decrease under 0.07 dB.
- Tremor modulations across periods with and without voluntary motion and limb load task demands using movement quantificationPublication . Faria , Paula; Patricio, Miguel; Philipiak, Gregor; Caramelo, Francisco; Januario, Cristina; Freire, Antonio; Castelo-Branco, MiguelUnderstanding the neurobiological mechanisms underlying different types of tremor and the altered functional connectivity of the involved areas is a timely goal in clinical neuroscience. If successful, this quest may open new perspectives on how to achieve tremor modulation, which is notably relevant, in Parkinson's disease (PD). Tremor can be characterized by simple parameters such as frequency and amplitude. It is therefore prone to be objectively targeted by neuromodulation and quantitatively investigated using multimodal techniques, such as, accelerometry, EMG and functional Magnetic Resonance Imaging (fMRI). Embarking on the latter challenge requires an a priori knowledge of how effective functional connectivity is altered in PD tremor. This works aims to ascertain which postural and voluntary movement tasks with distinct types of physical load are suitable for designing efficient fMRI protocols, by performing an accelerometry analysis to measure spontaneous and imposed tremor modulation on cohorts of PD patients, essential tremor patients and a group of voluntary healthy controls.
- Sandy beach macrofaunal assemblages as indicators of anthropogenic impacts on coastal dunesPublication . Bessa, Filipa; Cunha, David; Gonçalves, Sílvia; Marques, João CarlosOcean sandy beaches are iconic recreational assets to society and have undergone rapid degradation caused by both natural and anthropogenic pressures. A major effect of urbanisation on biota stems from artificial structures placed in aquatic systems. While the installation of these structures has been widespread, our understanding of how they impact shoreline habitats and fauna is relatively limited. On the sandy Leirosa Beach, on the European Atlantic coast (Portugal), a decade of cumulative impacts was recorded, with disruption of the frontal dune, dune nourishment and the incorporation of geotextiles to reconstruct the dune and maintain it as an artificial structure. Two years after the dune rehabilitation process at Leirosa Beach, seasonal sampling campaigns (from spring 2010 to winter 2011) were carried out to assess the effects of the artificial dune (and the first signs of its eventual disruption) on macrofauna compared to a natural dune on the same beach. During the study period, the rehabilitated foredune maintained the average slope, with similar sediment characteristics (finer sediments) when compared with the natural dune system, with no physical significant differences being appreciated between the two sites. The macrofaunal assemblages were represented especially by crustaceans (amphipods and isopods), with similar mean total density, taxon richness and diversity between sites. Special attention was given to the supralittoral species, and the results revealed that the natural zone harboured a significantly higher density of sandhopper Talitrus saltator with respect to the artificial zone. PERMANOVA results detailed the significant difference that occurred, particularly during the warmer seasons (spring and summer 2010), the recruitment period described for this species along this coast. In fact, SIMPER analysis revealed that T. saltator accounted for 46% of the dissimilarities between the natural and artificial dune sites. The presence of geotextiles extending across the supralittoral zone appeared, on the one hand, to allow for the presence of talitrids, but the application of textiles around the area prevented them from burrowing, thus causing them to avoid the rehabilitated area. The results highlighted the potentially negative effects of this artificial dune system if textile disruption continues, and the usefulness of T. saltator as an effective and reliable ecological indicator for these ecosystems. Thus, evaluating the risks and magnitude of human interventions is a major challenge for sandy beach ecologists, and baseline information is required if we are to better understand how resident macrofaunal species deal with future impact scenarios.
- Production of thermoplastics matrix preimpregnated materials to manufacture composite pultruded profilesPublication . Novo, P.J.; Nunes, J.P.; Silva, J.F.; Tinoco, V.; Marques, A.T.The aim of this work is to optimize the production of new continuous carbon fibers reinforced polypropylene matrix pre-impregnated materials (towpregs) continuously processed by dry deposition of polypropylene (PP) powder by our own developed dry coating line. The processing of the produced towpregs by pultrusion, using a prototype equipment, was also optimized. The optimization of both processes was made by studying the influence of the most relevant processing parameters in the final properties of the produced towpregs and composites. The method of Taguchi/DOE (Design of Experiments) was used to allow the determination of the optimal processing windows. The possibility of using maleic anhydride as compatibilizer for polypropylene reinforced carbon fiber composites (CF/PP) was also analyzed. A pre-consolidate tape was produced by the melting cross-head extrusion process and its proprieties compared with those of towpregs. Finally, towpregs were characterized by scanning electron microscopy (SEM) and visual analysis. Their polymer mass contents were determined and the final pultruded composite profiles were also submitted to tensile, interlaminar, flexural, calcination and optical microscopy tests.
- Refletindo sobre a Prática Pedagógica em Educação de Infância e 1.º CEB. A estruturação do princípio da cardinalidade no desenvolvimento de competências de contagem de objetos com crianças de três anos.Publication . Ribeiro, Patrícia Alexandra Henriques; Rodrigues, Marina Vitória Valdez Faria; Reis, Susana Alexandre dos
- A comparison of 3D poly(ε-caprolactone) tissue engineering scaffolds produced with conventional and additive manufacturing techniques by means of quantitative analysis of SR μ-CT imagesPublication . Brun, F; Intranuovo, F; Mohammadi, S; Domingos, M.; Favia, P; Tromba, GThe technique used to produce a 3D tissue engineering (TE) scaffold is of fundamental importance in order to guarantee its proper morphological characteristics. An accurate assessment of the resulting structural properties is therefore crucial in order to evaluate the effectiveness of the produced scaffold. Synchrotron radiation (SR) computed microtomography (μ-CT) combined with further image analysis seems to be one of the most effective techniques to this aim. However, a quantitative assessment of the morphological parameters directly from the reconstructed images is a non trivial task. This study considers two different poly(ε-caprolactone) (PCL) scaffolds fabricated with a conventional technique (Solvent Casting Particulate Leaching, SCPL) and an additive manufacturing (AM) technique (BioCell Printing), respectively. With the first technique it is possible to produce scaffolds with random, non-regular, rounded pore geometry. The AM technique instead is able to produce scaffolds with square-shaped interconnected pores of regular dimension. Therefore, the final morphology of the AM scaffolds can be predicted and the resulting model can be used for the validation of the applied imaging and image analysis protocols. It is here reported a SR μ-CT image analysis approach that is able to effectively and accurately reveal the differences in the pore- and throat-size distributions as well as connectivity of both AM and SCPL scaffolds.
- Refletindo sobre a Prática Pedagógica : Ideias sobre os cientistas em alunos do 1.º ano do ensino básicoPublication . Vicente, Catarina Santos; Rebelo, Isabel Sofia Godinho da Silva