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Ground recycled glass powder as a sustainable alternative to fly ash in low-carbon concrete
( 2026 ) Jesus, Carlos Manuel Gonçalves; Martins, Roseli; Reis, Rui; Malheiro, Raphaele Lira Meireles Castro; Ribeiro, Manuel; Camões, Aires
The increasing limitation in the availability of traditional supplementary cementitious materials (SCM), particularly coal fly ash (FA), has intensified the need for alternative solutions capable of ensuring both technical performance and environmental sustainability in cement-based materials. In this context, waste glass derived from soda–lime glass emerges as a promising option, contributing to circular economy principles and to the reduction of CO₂ emissions associated with clinker production. The study, developed within the framework of the GlassCON_4low project, aims to evaluate the feasibility of using finely ground glass powder (GP) as a SCM, assessing its pozzolanic activity and its influence on the mechanical and durability performance of concrete. The research has two main phases. First, mortars are produced with cement replacement levels of 15%, 25%, 35% and 50% by volume. Their mechanical behaviour is assessed and complemented by thermogravimetric analyses. Second, based on these results of first, two replacement levels are selected to reproduce in concrete mixtures. The concretes are subsequently characterised in terms of compressive strength at 7, 28 and 90 days, as well as durability indicators, including water absorption by immersion and capillarity, chloride diffusion and resistance to carbonation. The outcomes of this study aim to demonstrate the technical feasibility of using GP as a SCM in concrete, contributing to the development of more sustainable and durable construction solutions aligned with current technical, environmental and resource-efficiency challenges.
Low paternal postpartum depression buffers the association between maternal prenatal depression and preschoolers' internalizing and externalizing symptoms
( 2026 ) Costa, Cláudia da Silva; Pinto, Tiago Miguel; Field, Tiffany; Figueiredo, Bárbara
Examining the impact and interplay of maternal and paternal perinatal mental health problems enhances understanding of the etiology of mental health problems in early childhood. This study investigated associations between maternal and paternal prenatal (first trimester) and postnatal (3 and 30 months) anxiety and depression symptoms and preschoolers' internalizing and externalizing symptoms. The sample included 115 preschoolers and their parents (N = 230) recruited during the first trimester of pregnancy at a Portuguese health facility. Mothers and fathers completed anxiety and depression measures during the first trimester, at 3 and 30 months postpartum, and the Child Behavior Checklist 1.5–5 (CBCL) at 30 months. Multilevel linear models and moderation models were tested. Maternal depression symptoms in the first trimester, paternal depression symptoms at 3 months postpartum, and their interplay were prospectively associated with higher preschoolers' internalizing and externalizing scores at 30 months. When fathers reported low depression symptoms 3 months postpartum, mothers’ depression symptoms during the first trimester were not associated with preschoolers’ internalizing and externalizing scores at 30 months. This suggests that low paternal postnatal depression symptoms can buffer the adverse effect of maternal prenatal depression symptoms. Addressing maternal and paternal perinatal mental health could contribute to preventing preschoolers’ internalizing and externalizing problems.
Rir é o Melhor Remédio: perceções humorísticas entre Portugal e China
( 2026 ) Moreira, Diogo Rêgo; Martins, João Marcelo; Lam, Sun
O presente trabalho de dissertação encontra-se dividido em três grandes partes. Em primeiro lugar, analisa-se o riso numa perspetiva teórica, identificando as principais abordagens ao fenómeno e as respetivas fundamentações. Em segundo lugar, estuda-se a evolução histórica do humor em Portugal e na China, observando de que modo o conceito se transformou ao longo do tempo através de manifestações humorísticas concretas. Por fim, apresenta-se uma breve análise da contemporaneidade em ambos os países, delineando os traços que, do ponto de vista estético, mais caraterizam o humor em cada contexto. Com base nesses elementos, procede-se a uma comparação Portugal e China, assinalando semelhanças e diferenças, com o intuito de tecer constatações que permitam a aproximação das duas culturas.