120 research outputs found

    Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities

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    Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students’ attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student’s attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008). The participants were 470 students (267 girls – 56.8% and 203 boys – 43.2%), aged 14–16 years old (m D 14.3 0.58). The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ) and, the Reasoning Test Battery (RTB) was used to assess the students reasoning abilities. Achievement was measured using the students’ quarterly (9-week) grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (b), calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student’s grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with student’s achievement in Physics-chemistry, indicating that both attitudinal and cognitive variables should be taken into account on science education as well as in educative intervention

    A construção sustentável na perspetiva dos geomateriais utilizados na Província da Huíla, Angola

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    A construção sustentável centra-se na busca da necessidade de maior eficiência energética, menor preço e maior durabilidade, com o objetivo de obter uma edificação que não agrida o meio ambiente, mas também com melhor conforto térmico, com reduzida necessidade de consumo de energia e com melhoria da qualidade de vida dos seus moradores. Na província da Huíla, Angola, existem inúmeras habitações de terra crua que constituem uma verdadeira herança cultural e que têm sido construídas com base em métodos e técnicas ancestrais que respeitam o ambiente. Os materiais utilizados e as características construtivas diferem, sobretudo, em função do rendimento das próprias famílias e dos materiais disponíveis, sendo o adobe, o método construtivo em terra que assume uma maior presença nesta região, não obstante a existência de edificações de pau-a-pique e, mais recentemente, em blocos de terra comprimida. O principal objetivo deste estudo é avaliar e relacionar a composição mineralógica e textural dos solos com as respetivas características físicas e mecânicas, de forma a identificar as suas potencialidades e limitações como material de construção em terra crua nesta região. Para o efeito, foram colhidas 8 amostras de solos e adobes fabricados nos respetivos locais, de modo a realizarem-se ensaios específicos cujos resultados possibilitaram a identificação e caracterização destes geomateriais. Neste trabalho, realizaram-se os ensaios in-situ e laboratoriais para determinar as propriedades mineralógicas (DRX), as físicas (granulometria, consistência, expansibilidade, densidade), as mecânicas, os ensaios Geelong e o ensaio de avaliação do ciclo húmido/seco, de acordo com as normas Neozelandesas, NZS 4298 (1998) e 4297 (1998). Esta investigação contribui para a caracterização dos geomateriais utilizados na construção em terra crua nesta região de Angola, contribuindo assim, para o desenvolvimento de soluções construtivas sustentáveis e com características melhoradas, de conforto, segurança e de durabilidade

    Insulation lifetime improvement of polyimide thin film neural implants

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    Objective. This work deals with studying and improving the insulation lifetime of polyimideinsulated thin film neural implants, or related polyimide-based medical implants. Approach. The evolution of the leak impedance of insulated conductors was investigated in saline water at 40 °C. The fabrication process as commonly found in literature for polyimide/platinum/ polyimide microelectrode arrays was compared with three possible improvements: one based on lowering the curing temperature of the lower layer, one based on chemical activation and one based on an additional plasma activation step. Main results. The lower curing temperature process was found to yield a 7.5-fold improved lifetime compared with the state of the art process. Also, the leak impedances found after soak testing are an order of magnitude higher compared to the standard process. Significance. By improving the lifetime and insulation impedance of polyimide insulation with one order of magnitude, this work increases the applicability of polyimide in chronic thin film neural implants considerably.status: publishe

    Depósitos periglaciários da Serra da Cabreira, NW de Portugal: Cartografia geomorfológica e morfometria

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    Faz-se uma análise morfométrica de depósitos periglaciários da Serra da Cabreira (1262 m), focando os macrogelifractos graníticos da vertente NW. A análise foi suportada por medições de campo e interpretação de ortofotomapas. Os resultados mostram que o depósito analisado é composto por blocos sub-verticais e subhorizontais que atingem os 7 m de comprimento no eixo A. A distribuição dos macrogelifractos, do setor superior ao inferior, apresenta padrões diferentes, em que o tamanho diminui para jusante. A orientação do eixo A dos blocos sub-horizontais segue o declive da vertente. Nos setores médio e inferior, o arranjo dos blocos sub-verticais parece definir estruturas-barreira

    A retrospective study

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    Funding Information: Thanks to the research team of INIS/CISA (Manuela Galangue, Joltim Quivinja, Celestina Gaston, and Rui Van‑Dunen), Instituto Nacional de Sangue (Emiliana Lunbungululo, Eunice Manico, Alberto Sozinho, and Deodete Machado), and Clínica Girassol (Alice Teixeira, Domingos Alfredo, and Ngueza Loureiro) for the data collection, technical/administrative support, and testing. Publisher Copyright: © 2023 The Authors. Health Science Reports published by Wiley Periodicals LLC.Background and Aims: SARS-CoV-2 infection is a public health concern. Several aspects related to the pattern of infection remain unclear. This study aimed to investigate the blood pressure pattern among blood donors exposed to SARS-CoV-2 in Luanda, Angola, a sub-Saharan African country. Methods: We performed a retrospective analysis containing 343 blood donors from December 2019 to September 2020. Parametric tests compared means while χ2 and logistic regression checked features associated with high blood pressure and were considered significant when p 0.05). A significant link was observed, between the Rhesus factor and blood pressure status (p = 0.032). Conclusion: We showed important variations in blood pressure indices of the Angolan population exposed to SARS-CoV-2. Older age and non-O blood groups appear to be important biological factors for SARS-CoV-2 infection, as well as the risk of developing cardiovascular disease after or during SARS-CoV-2 exposure. Further studies assessing the impact on cardiovascular functions with ongoing or long-term SARS-CoV-2 exposure in individuals from resource-limited countries should be considered.publishersversionpublishe

    Novel approach for a controlled delivery of essential Oils during long-term maize storage: clove bud and pennyroyal oils efficacy to control sitophilus zeamais, reducing grain damage and post-harvest losses

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    Maize grains represent a significant contribution for assuring food safety all over the globe. Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), also known as the maize weevil, is one of the most destructive pests in stored maize, causing qualitative and quantitative losses. To control S. zeamais populations in maize storage sites, synthetical chemical insecticides are applied. However, these are often used wastefully, have environmental implications, and can induce the development of resistant populations. In this work, the insecticidal and grain protecting efficacy of an innovative macro-capsule delivery device, loaded with essential oils from Clove bud and Pennyroyal, as well as their combined solutions, was tested against naturally S. zeamais-infested maize grains. The blend of both compounds incorporated in a controlled release device reduced losses by more than 45% over a long storage period of twenty weeks, diminishing the survivability of maize weevils by over 90%. The usage of the blend at a concentration of 370 L L1 air with an antioxidant showed the best results, however, by halving the concentration 185 L L1 air , a significant control of S. zeamais populations was still achieved.info:eu-repo/semantics/publishedVersio

    Innovation for Sustainability and Networking

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    Throughout human history, innovation has been the main factor in adapting humanity to its settings. On the basis of earlier practice, human creativity allows the finding of new, permanent ways to do things. their applications encourage new spaces, new necessities and new lifestyles. Innovation has been an element of human capacities from its earlier stages, but it has been recognized only recently as a clear device of social and economic change

    Portuguese recommendations for the use of biological and targeted synthetic diseasemodifying antirheumatic drugs in patients with rheumatoid arthritis – 2020 update

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    Objective: To update the recommendations for the treatment of rheumatoid arthritis (RA) with biological and targeted synthetic disease-modifying antirheumatic drugs (bDMARDs and tsDMARDs), endorsed by the Portuguese Society of Rheumatology (SPR). Methods: These treatment recommendations were formulated by Portuguese rheumatologists taking into account previous recommendations, new literature evidence and consensus opinion. At a national meeting, in a virtual format, three of the ten previous recommendations were re-addressed and discussed after a more focused literature review. A first draft of the updated recommendations was elaborated by a team of SPR rheumatologists from the SPR rheumatoid arthritis study group, GEAR. The resulting document circulated among all SPR rheumatologists for discussion and input. The level of agreement with each of all the recommendations was anonymously voted online by all SPR rheumatologists. Results: These recommendations cover general aspects such as shared decision, treatment objectives, systematic assessment of disease activity and burden and its registry in Reuma.pt. Consensus was also achieved regarding specific aspects such as initiation of bDMARDs and tsDMARDs, assessment of treatment response, switching and definition of persistent remission. Conclusion: These recommendations may be used for guidance of treatment with bDMARDs and tsDMARDs in patients with RA. As more evidence becomes available and more therapies are licensed, these recommendations will be updated.info:eu-repo/semantics/publishedVersio

    Low frequency of TERT promoter mutations in gastrointestinal stromal tumors (GISTs).

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    Somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene, mainly at positions c. − 124 and c. − 146 bp, are frequent in several human cancers; yet its presence in gastrointestinal stromal tumor (GIST) has not been reported to date. Herein, we searched for the presence and clinicopathological association of TERT promoter mutations in genomic DNA from 130 bona fide GISTs. We found TERT promoter mutations in 3.8% (5/130) of GISTs. The c. − 124C4T mutation was the most common event, present in 2.3% (3/130), and the c. − 146C4T mutation in 1.5% (2/130) of GISTs. No significant association was observed between TERT promoter mutation and patient’s clinicopathological features. The present study establishes the low frequency (4%) of TERT promoter mutations in GISTs. Further studies are required to confirm our findings and to elucidate the hypothetical biological and clinical impact of TERT promoter mutation in GIST pathogenesis.This project was partially supported by Barretos Cancer Hospital internal research funds (PAIP) and CNPq Universal Grant (476192/2013-7) to RMR. NCC is a recipient of an FAPESP Doctoral Fellowship (2013/25787-3). Further funding from the project ‘Microenvironment, metabolism and cancer’ that was partially supported by Programa Operacional Regional do Norte (ON.2—O Novo Norte) under the Quadro de Referência Estratégico Nacional (QREN) and the Fundo Europeu de Desenvolvimento Regional (FEDER). IPATIMUP is an Associate Laboratory of the Portuguese Ministry of Science, Technology and Higher Education that is partially supported by the FCT
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