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Nickel alloys and composites are interesting engineering materials as a result of a combination of mechanical, corrosion and wear resistance at service temperatures that exceed those of steels and steel-based materials. The present study aimed at sintering Ni-graphite composites from NiO-SiC mixtures and investigate the in-situ formation of graphite. NiO powders were mixed with SiC (0, 3, 5 and 10 wt.%) and attrition-milled during 1 h. The mixtures were then granulated using 1.5 wt.% paraffin in hexane solution and uniaxially pressed under 400 MPa. The cylindrical pellets were then sintered at 1200 ºC. The sintered materials were characterized by density measurements, dilatometric and microstructural analyses, as well as Vickers microhardness. The results showed that Ni-graphite composites were successfully produced from NiO-SiC mixtures with full reduction of NiO and dissociation of SiC to form a Ni-Si matrix and graphite nodules.

Objetivo: conhecer os níveis de depressão e sintomas depressivos em angolanos com HIV. Método: estudo descritivo e misto, com estratégia exploratória sequencial, em período pré-pandêmico em um hospital público de Angola. Realizou-se entrevistas semiestruturadas, com aplicação do Inventário de Depressão de Beck. Para fins de análise, considerou o conceito de depressão a partir da classificação internacional de doenças. Resultados: prevaleceu depressão leve a moderada para ambos os sexos e estado civil. No G1, a maioria além da tristeza ou infelicidade não conseguem suportar a angústia, alguns verbalizam ter consciência de que os choros não os levará a ter vida anterior desta realidade. Agora se sentem irritados o tempo todo e não sentem mais prazer nas coisas como antes. No G2, expressaram ideias e sentimentos suicidas, estavam desanimados quanto ao futuro, percebem-se fracassados mais do que uma pessoa sem a doença, e adiam a tomada de decisão mais do que o costume. Conclusão: embora não tenha prevalecido formas severas (graves) de depressão, a ocorrência de sintomas negativos em variadas esferas da vida pode evoluir, especialmente no contexto angolano.

Recently, efforts have been made to add programming activities to the curriculum that promote computational thinking and foster 21st-century digital skills. One of the programming modalities is the use of Tangible Programming Languages (TPL), used in activities with 4+ year old children. In this review, we analyze solutions proposed for TPL in different contexts crossing them with non-TPL solutions, like Graphical Programming Languages (GPL). We start to characterize features of language interaction, their use, and what learning activities are associated with them. Then, in a diagram, we show a relation between the complexity of the languages with factors such as target age and output device types. We provide an analysis considering the type of input (e.g., TPL versus GPL) and output devices (e.g., physical robot versus graphical simulation) and evaluate their contribution to further insights about the general trends with respect to educational robotic systems. Finally, we discuss the opportunities to extend and improve TPLs based on the different solutions identified.

This paper seeks to identify the pedagogical resources used by kindergarten, primary and secondary teachers in Azores Islands. Additionally, an investigation will be made into how these resources are mobilized in teachers’ pedagogical practice, with the aim of understanding to what extent digital resources, particularly learning objects, are present in schools. For this purpose, a study was developed, which included a questionnaire survey conducted online, and sent to teachers in 2021/22. A total of 426 answers allowed us to conclude that the use of pedagogical resources is still far from the current and emerging need to mobilize digital resources, particularly learning objects, as a tool to enhance meaningful learning.