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Interdisciplinary studies of rocky slopes stability have been performed on Northern Portugal, that allowed to establish a design methodology. This approach carries together the use of more traditional techniques, with the application of more recent technologies, such as unmanned aerial vehicles. This work presents a set of procedures that have been applied successfully in several case studies, describing the different stages, with an emphasis on the production of a ground threedimensional model. This model is generated from photographs obtained with successive drone flights, with overlapping. It is the support for the development of subsequent stages, especially for the characterisation of the trajectories of rockfalls and modelling, the development of susceptibility mapping and of rock slope hazard. In this context, the Natural Slope Quality Index (N-SQI ), an adaptation of the Slope Quality Index (SQI), orientated to natural slopes, is presented. The Block Gravity Number (BGN), created in order to hierarchise rock blocks, selecting them for modelling, is also proposed.

Ti-based materials are widely used for dental and orthopaedic implant applications due to their adequate mechanical properties, corrosion behaviour and biocompatibility. However, these materials are biologically inert and display poor wear resistance. In one of the most studied processes that aims to overcome these drawbacks, Ti surfaces are often covered by anodic oxide films with the incorporation of bioactive agents such as Ca and P. Although there are several works on the tribocorrosion behaviour of MAO-treated Ti surfaces, the influence of electrolyte composition on the corrosion kinetics under sliding is yet to be fully understood. In the present work, anodic oxide films were produced on cp-Ti surfaces with different calcium acetate concentrations in the electrolyte. Tribocorrosion behaviour was investigated by reciprocating sliding tests performed in 8 g/L NaCl solution at body temperature, under potentiostatic conditions. The results showed that higher concentrations of calcium acetate had a detrimental effect on tribocorrosion kinetics, however, they resulted in less mechanical damage due to alterations in the topography and structure of the MAO layer.

The electrical conductivity (σ) and Seebeck coefficient (S) at temperatures from 40 °C to 100 °C of melt-processed polypropylene (PP) composites filled with 5 wt.% of industrial-grade carbon nanofibers (CNFs) is investigated. Transmission Electron Microscopy (TEM) of the two Pyrograf® III CNFs (PR 19 LHT XT and PR 24 LHT XT), used in the fabrication of the PP/CNF composites (PP/CNF 19 and PP/CNF 24), reveals that CNFs PR 24 LHT XT show smaller diameters than CNFs PR 19 LHT XT. In addition, this grade (PR 24 LHT XT) presents higher levels of graphitization as deduced by Raman spectroscopy. Despite these structural differences, both Pyrograf® III grades present similar σ (T) and S (T) dependencies, whereby the S shows negative values (n-type character). However, the σ (T) and S (T) of their derivative PP/CNF19 and PP/CNF24 composites are not analogous. In particular, the PP/CNF24 composite shows higher σ at the same content of CNFs. Thus, with an additionally slightly more negative S value, the PP/CNF24 composites present a higher power factor (PF) and figure of merit (zT) than PP/CNF19 composites at 40 °C. Moreover, while the σ (T) and S (T) of CNFs PR 19 LHT XT clearly drive the σ (T) and S (T) of its corresponding PP/CNF19 composite, the S (T) of CNFs PR 24 LHT XT does not drive the S (T) observed in their corresponding PP/CNF24 composite. Thus, it is inferred in PP/CNF24 composites an unexpected electron donation (n-type doping) from the PP to the CNFs PR 24 LHT XT, which could be activated when PP/CNF24 composites are subjected to that increase in temperature from 40 °C to 100 °C. All these findings are supported by theoretical modeling of σ (T) and S (T) with the ultimate aim of understanding the role of this particular type of commercial CNFs on the thermoelectrical properties of their PP/CNF composites.

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Aneurismas de artéria coronária são dilatações em um segmento arterial. Tais alterações já decorriam de certas patologias conhecidas. No entanto, com a chegada da pandemia causada pela COVID-19, constatou-se um aumento nos casos de crianças com aneurismas coronários quando associados à Síndrome Inflamatória Multissistêmica Pediátrica pelo SARS-CoV-2, denominada PIMS-TS. O presente estudo busca analisar a incidência de aneurismas de artéria coronária na Síndrome Inflamatória Multissistêmica Pediátrica por COVID-19. Foram analisados 22 artigos originais relacionados ao tema, entre 2020 e 2021, em inglês e português, através das bases de dados do PubMed, LILACS, Google Scholar e SciELO. Os critérios de exclusão utilizados foram: Livros, documentos de projetos de dissertação, resumos em eventos, editoriais, revisões de literatura, relatos de caso isolados, artigos que não cumpriam os critérios de inclusão e artigos duplicados. Diante dos estudos analisados, conclui-se que a incidência de aneurismas de artéria coronária ocorre por meio da PIMS-TS. A menor taxa de incidência encontrada foi de 2,3%, a maior, de 79,92%, com média geral de ± 17,34%.

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