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- Effect of nickel on the mechanical properties of spray-formed Al-15Si-2Cu alloy at elevated temperaturesPublication . Goudar, Dayanand M.; Alavandi, Mehabubsubahani R.; Bhat, Subraya Krishna; Bommenahalli, Raghukumar; Kurahatti, Rajashekar V.; Pinto, Deesy G.; Raju, K.; Pinto, Deesyat different temperatures was examined and evaluated with that of the as-cast (AC) alloy. The microstructure of SF alloys revealed uniformly distributed spherical shaped primary silicon and eutectic silicon phases along with fine Ni and Cu intermetallic particles dispersed throughout the equiaxed Al matrix. The microstructure of AC alloys consisted of coarse primary Si, flake-type eutectic phase, Cu-rich intermetallics with a complex branched morphology and a network of short strips. The mechanical properties of the alloys were assessed at temperatures of 30◦C, 100◦C, 200◦C and 300◦C. The SF alloys exhibited higher hardness than AC alloys at all temperatures with a maximum increase of 74 % at 30◦C. The hardness of alloys showed a decreasing trend with increasing temperature. The mechanical strength of SF alloys was higher than that of the AC alloys across the entire temperature range from 30◦C to 300◦C with a decrease in ultimate tensile strength (UTS) by 4–6 % at 250◦C. The SF alloys demonstrated a significant increase in UTS (25 % at 30◦C and 40 % at 300◦C) compared to the AC alloys. The Al-15Si-2Cu-2Ni alloy showed highest increase (14.3–18.6 %) and Al-15Si-2Cu-6Ni alloy showed the lowest increase (10.5 % to 14 %) in percent elongation between 30◦C and 300◦C.
- 2024 U.S. presidential elections: an event study for U.S. and non-U.S. fossil fuel and renewable listed firmsPublication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno; Martins, António; Albuquerque, Bruno; Sardinha, LuisThis study examines the short-term market effect of Donald Trump’ victory in the 2024 US presidential election on largest US and non-US listed worldwide fuel fossil and renewable firms. Employing an event study meth odology, we observe a negative and statistically significant stock price reaction for worldwide renewable listed firms. An analysis by economic zones reveals the existence of negative abnormal returns for renewable energy firms in the US, Europe, India and in the rest of the world. In the case of China, abnormal returns are not sta tistically significant. With respect to worldwide fossil fuel listed firms, abnormal returns are generally not sta tistically significant. However, regarding US firms, we observe positive and statistically significant abnormal returns. These abnormal returns are explained by the change of US energy policy (pro-oil and gas policy) and the expected cut in subsidies and lower profitability of investments in green energies. Finally, our study provide insight into which firm-specific characteristics emerge as value drives around US presidential elections. The results show that despite the change in environmental policy in the US, favourable to fossil energy, the stock markets reward firms with high environmental ratings. Overall, our results indicate that 2024 US presidential election, for implying a change in US energy policy, has relevant policy implications for energy listed firms.
- Containerizing and evaluating the WRF model for cloud-based HPCPublication . Gouveia, Diogo Manuel Sales; Baras, Karolina; Vieira, Rui Ricardo AlmeidaNumerical models are mathematical representations that solve algebraic or differential equations to simulate phenomena across time and space. Some models, such as the Weather Research and Forecasting (WRF) model, are applied to weather prediction, providing valuable information to individuals, companies, institutions, and governments on potential future events. However, the WRF model can become highly computationally demanding, requiring increasingly power ful hardware resources with the increase of the resolutions and complexity of the simulations. High-Performance Computing (HPC) allows users to leverage powerful instances tailored to their needs, providing the necessary hardware resources for running complex WRF simulations. Mean while, cloud computing presents an enticing option for computationally demanding programs, offering advantages such as economies of scale, high reliability, and availability. On the software side, compiling, configuring, and installing multiple libraries are essential to exploit WRF’s po tential, which can be an arduous task. This study explores a cloud-enabled approach using pre configured Docker images and compares it to on-premises, HPC, and cloud solutions. We also analyze whether cloud computing is economically and performance-wise viable, using a compa rable base architecture across multiple cloud providers, and assess if the convenience of Docker meets the requirements despite potential overhead.
- Parents and athletes’ perceptions of parental involvement practices in youth basketballPublication . Lopes, Maria V.; Ihle, Andreas; Gouveia, Élvio Rúbio; Marques, Adilson; Cinarli, Fahri Safa; França, Cíntia; Ihle, Andreas; Gouveia, Élvio Rúbio; Marques, Adilson; França, CíntiaParental involvement in youth sports is an increasingly relevant topic because of its key implications for children’s development in youth sports. This study’s aims are threefold: (1) to investigate parental involvement practices based on parents’ previous sports experiences, (2) to examine athletes’ and parents’ perceptions on parental involvement practices across different age categories, and (3) to compare the athletes’ and parents’ overall perceptions on parental involvement practices. In total, 423 participants (151 youth players and 272 parents) completed the Parental Behaviors in Sports (PBSP) questionnaire. The PBSP includes separate versions for parents and athletes, each assessing five key dimensions: (1) sports support, (2) competition attendance, (3) technical influence, (4) performance pressure, and (5) sports expectations. In the parents’ group, 154 participants (56.6%) reported previous sports experience. No statistically significant differences were observed in the PBSP dimensions between parents with and without previous sports experience. Parents’ years of sports experience negatively correlated with performance pressure (r = −0.155, p = 0.013) and expectations (r = −0.149, p = 0.017). Age group analysis showed lower competition attendance in the U18 group and higher expectations in the U12 group. When comparing parents’ and athletes’ responses, statistically significant differences emerged in all PBSP dimensions except for performance pressure. These findings underscore the importance of aligning parental involvement with children’s experiences to foster enjoyment, reduce pressure, and support sustained engagement in youth sports.
- Influência dos manuais digitais na atenção e concentração dos alunosPublication . Passos, Sofia Raquel Aguiar; Garcês, Soraia FernandesO presente estudo tem como objetivo analisar o impacto da utilização de manuais digitais no desempenho da atenção e concentração de alunos da Região Autónoma da Madeira (RAM). Esta investigação integra-se no projeto TASRAM-CIT, um projeto longitudinal desenvolvido em parceria com a Universidade da Madeira e a Secretaria Regional de Educação, Ciência e Tecnologia. Foram avaliados 704 alunos do ensino básico e secundário em dois momentos distintos, com recurso ao teste de atenção D2, validado e adaptado para a população portuguesa. A amostra foi dividida entre dois grupos: alunos que utilizavam manuais digitais e alunos que utilizavam manuais físicos. Os resultados revelaram melhorias significativas nos indicadores de atenção e concentração em ambos os grupos ao longo do tempo. A análise estatística recorreu a testes t de Student e ANOVA mista, com verificação dos pressupostos de normalidade e homogeneidade. As diferenças encontradas apresentaram significância estatística e efeitos moderados a elevados em diversas variáveis, reforçando a validade dos resultados. Apesar da perceção positiva associada à utilização dos manuais digitais, os dados sugerem que a sua eficácia depende fortemente da forma como são integrados pedagogicamente. Este estudo contribui para a reflexão sobre os efeitos reais da digitalização educativa, reforçando a necessidade de uma implementação consciente, acompanhada de formação contínua para docentes, e adaptada às realidades das escolas. São discutidas implicações práticas, limitações metodológicas e propostas para investigações futuras, com enfoque em estudos longitudinais e de intervenção que explorem mais profundamente os efeitos da tecnologia nos processos cognitivos e no rendimento escolar.
- Associations between pulmonary function and muscle strength in turkish national karate athletesPublication . Tokgoz, Gurkan; Cinarli, Sena; Akyol, Betül; Aygoren, Caner; Beykumul, Aysegul; Larsen, Malte Nejst; Krustrup, Peter; França, Cíntia; Gouveia, Élvio Rúbio; Cinarli, Fahri Safa; França, Cíntia; Gouveia, Élvio RúbioBackground: Respiratory efficiency is considered important in karate due to its role in sustaining muscular performance during high-intensity actions. This study examined the association between pulmonary function and isometric muscle strength in national-level karate athletes. Methods: A total of 23 elite karate athletes (mean age: 23.0 ± 2.3 (mean ± SD) years) participated in the study. Pulmonary function was assessed using a digital spirometer, while isometric handgrip, lower back, and leg strength were measured using a dynamometer. The correlation between pulmonary function and isometric strength was analyzed, and linear regression was employed to examine the predictive capacity of pulmonary parameters for muscle strength. Results: The results revealed significant correlations, ranging from large to very large, between pulmonary function and isometric muscle strength, with correlation coefficients from 0.639 to 0.812 (p < 0.01). Pulmonary function was strongly associated with isometric strength, accounting for 27% to 67% of the variance (p < 0.05). Multiple regression analysis revealed that pulmonary function parameters accounted for 71% of the variance in handgrip strength, 47% in leg strength, and 71% in back strength (p < 0.05). Conclusions: These findings highlight the strong associations between pulmonary function and isometric muscle strength in elite karate athletes. The results emphasize the importance of pulmonary health and respiratory muscle function in athletic performance, particularly for sports requiring high-intensity, dynamic movements like karate. Future longitudinal studies are needed to explore the mechanisms underlying the association and potential implications, and for training and performance optimization.
- Consensual non-monogamies: social representations among family therapists, sex therapists, and sexologists in the Iberian contextPublication . Quintal, Lara Isabel Rodrigues da Silva; Portugal, Alda Patrícia Marques; Gonçalves, José Alberto RibeiroConsensual non-monogamies (CNM) have become increasingly visible in psychological and clinical research, yet there remains a substantial gap in understanding how these relational structures are perceived by mental health professionals with advanced training in fields such as family therapy and sexology. This study aims to explore the social representations held by family therapists, sexologists, and sex therapists regarding CNM. To investigate these representations, a qualitative, non-experimental approach was employed using the free word association method based on Abric’s Central Nucleus Theory, with data collected online from a non-probabilistic sample of Portuguese and Spanish therapists (N=156) and analysed through EVOC software. The analysis revealed that “relational diversity”, and “freedom” were central social representations across all Portuguese and Spanish professionals, while additional terms such as “complexity,” “confusing,” and “consent” varied in prominence depending on participants’ therapeutic experience and nationality. The results also suggest that while “relational diversity” and “freedom” are core elements in the social representations of CNM across samples, therapists without clinical experience working with CNM clients tend to associate it more strongly with terms like “confusing” and “complexity”. These results highlight the importance of including CNM-related content in therapist training programs, promoting less stigmatizing and more informed representations. Direct clinical exposure to these relationships may contribute to more sensitive, ethical, and informed interventions in the therapeutic context.
- Between kisses and bytes: cyber dating abuse and internet use in emerging adulthoodPublication . Saial, Ana Cristina; Portugal, Alda; Gouveia, Élvio Rúbio; Nascimento, Paulo; Satar, Muhammad; Relvas, Ana Paula; Portugal, Alda; Gouveia, Élvio RúbioAbstract Emerging adults use the internet to connect with intimate partners, which can promote closeness but also increase vulnerability to abusive behavior, such as cyber dating abuse (CDA). In this study, we explored the use of the internet and information and communication technologies (ICT) and determined the prevalence of CDA among 105 emerging adults, with an average age of 23.2 years (SD = 3.65). Through an online cross-sectional study, our results indicate that emerging adults spend an average of 6.67 h a day online (SD = 3.34), with 37.6% communicating with their partner for more than 5 h daily via ICT. A high prevalence of CDA was observed: 62.9% victimization and 74.3% perpetration, with an emphasis on controlling behaviors. This study explores the relationship between problematic internet use (PIU) and CDA and highlights the normalization of CDA behaviours.
- Bem-estar e diversidade sexual nos estudantes do ensino superior: o papel da saúde mental, o otimismo, o rendimento e a motivaçãoPublication . Fernandes, Diana Manuela Sousa; Pocinho, Margarida Maria Ferreira Diogo Dias; Gonçalves, José Alberto RibeiroO ingresso no ensino superior representa uma etapa desafiante, marcada por mudanças significativas que influenciam o bem-estar, a saúde mental e o desempenho académico dos estudantes. Estes desafios podem ser particularmente intensificados em estudantes LGBT+, frequentemente sujeitos a experiências de exclusão e discriminação. O presente estudo, teve como objetivo analisar de que forma o bem-estar se relaciona com a saúde mental, o otimismo, a motivação e o rendimento académico, em função da orientação sexual dos estudantes. A amostra foi constituída por 285 estudantes do ensino superior em Portugal, dos quais 129 se identificaram como heterossexuais e 156 LGBT+, com idades compreendidas entre os 18 e os 69 anos. Foram utilizados os seguintes instrumentos: Escala de Bem-Estar Experiencial, Escala de Ansiedade, Depressão e Stress (DASS-21), Escala de Otimismo e dois itens únicos, um sobre motivação e outro sobre o rendimento académico. Os resultados revelaram que os estudantes LGBT+ apresentaram níveis significativamente mais baixos de saúde mental, otimismo e motivação, mas níveis superiores de rendimento académico, em comparação com os estudantes heterossexuais. A análise de regressão indicou que, em ambos os grupos, o bem-estar se relacionou positivamente coma saúde mental, o otimismo e a motivação. Contudo, entre os estudantes LGBT+, o otimismo assumiu um peso preditivo mais acentuado, funcionando como um recurso de resiliência face ao stress minoritário. As implicações práticas são também apresentadas e discutidas.
- Characterizing psychomotor abilities of male handball players of different age categoriesPublication . Martins, Francisco; Śliż, Maciej; França, Cíntia; Sarmento, Hugo; Gouveia, Élvio Rubio; Campos, Pedro; Lopes, Helder; Przednowek, Krzysztof; Pestana Martins, João Francisco; França, Cíntia; Borges Sarmento, Hugo Miguel; Sarmento, Hugo; Gouveia, Elvio Rúbio; Gouveia, Élvio Rúbio; Pereira Campos, Pedro Filipe; Lopes, Helder; Przednowek, KrzysztofSports performance is highly influenced by players’ mental, emotional, and psychomotor abilities. Particularly in handball, training methods aim to maximize players’ performance by fusing physical conditioning with cognitive abilities. The aim of this research was twofold: (1) to characterize players’ psychomotor abilities according to their age categories (U14, U16, and U18), and (2) to analyze the differences between psychomotor abilities profiles according to players’ field positions. The study population comprised 75 male youth handball players (15.3 ± 1.5 years) from different competitive age groups (U14 = 20 players; U16 = 27 players; U18 = 28 players). The psychomotor abilities were evaluated using the Test2Drive system. Three tests were performed to measure psychomotor abilities: (a) a simple reaction time test (SIRT), (b) a choice reaction time test (CHORT), and (c) a spatial anticipation test (SPANT). The only statistically significant difference was observed in the percentage of correct answers in the SPANT, showing that U16 players had a higher rate of correct answers than the others. However, some trends were visible throughout the analysis: (i) the U16 group performed better in terms of reaction time in all the tests, (ii) right-wingers were always the ones who had the best percentage of correct answers, and (iii) central players had the best movement time performance. Future research should include youth players' maturation stage, body composition, and physical fitness performance to characterize their profile deeply and analyze their psychomotor abilities, considering other factors that can impact their sports performance.