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O impacto da inteligência artificial nos acidentes de trabalho
Publication . Belo, João Tomás Bernardo; Mendes, Jorge Manuel Barros
Esta dissertação explora o papel transformador da inteligência artificial (IA) no contexto da segurança e saúde no trabalho, com foco na estratégia nacional portuguesa AI Portugal 2030 e no quadro regulatório europeu, o AI Act. Inicialmente, apresenta-se uma resenha histórica sobre acidentes de trabalho e segurança ocupacional, destacando a evolução dos conceitos e práticas ao longo do tempo. São abordados os fundamentos de IA, incluindo definições fornecidas por sistemas como Grok, ChatGPT e Meta AI, complementadas por uma análise crítica e uma reflexão pessoal sobre o conceito de IA. A estratégia AI Portugal 2030 é analisada em profundidade, destacando os seus três eixos principais, o crescimento económico e inovação, excelência científica e desenvolvimento humano através da educação, qualificação e inclusão digital. A estratégia enfatiza a importância de uma IA ética, transparente e inclusiva, promovendo a modernização da Administração Pública. O AI Act é examinado como um marco regulatório que equilibra inovação e responsabilidade, abordando dimensões jurídicas, éticas, económicas e tecnológicas para garantir o uso seguro da IA. No contexto dos acidentes de trabalho, a presente dissertação avalia o potencial da IA, especialmente em equipamentos de proteção individual com IA analisando os seus benefícios, como a deteção de riscos em tempo real, e os desafios, como custos elevados, dependência tecnológica e questões de privacidade. Casos reais ilustram a aplicação prática da IA, enquanto a questão da responsabilidade por falhas tecnológicas é discutida, destacando a complexidade da atribuição de culpa. Conclui-se que a IA oferece oportunidades significativas para melhorar a segurança no trabalho, mas a sua implementação exige formação contínua e uma regulação robusta para assegurar confiança e sustentabilidade.
The impact of microplastics and copper on sex ratio and oxidative stress: analysis in zebrafish intestine, gonad and brain
Publication . Ferreira, Carlos Rodrigues; Baptista, Teresa Maria Coelho; Monteiro, Sandra Mariza; Santos, Dércia Cabral
The increasing prevalence of emerging pollutants, such as microplastics and heavy metals, poses a major threat to aquatic ecosystems. This study aimed to investigate the individual and combined effects of copper (Cu), polyethylene (PE) and polystyrene (PS) microplastics on embryonic development and sexual differentiation in zebrafish (Danio rerio), as well as biochemical responses in target organs. Exposure trials revealed that copper, at environmentally relevant concentrations, caused high embryonic mortality, developmental delays, and altered heart rates. PE exposure alone induced sublethal effects, including a feminisation trend in sex differentiation. Co-exposure amplified these adverse outcomes, confirming a synergistic interaction. Histological analyses revealed disruptions in sexual differentiation, while biochemical assays demonstrated organ-specific responses. The brain appeared highly vulnerable to copper neurotoxicity, the gonads showed limited antioxidant adaptation, and the intestine displayed subtle but significant changes. These findings highlight the ecological relevance of multi-contaminant exposure scenarios and reinforce zebrafish as a powerful model for toxicological studies. Overall, the interaction between microplastics and heavy metals may compromise reproductive success and population sustainability in aquatic organisms.
Thermo-kinetic curing model for stereolithographic applications
Publication . Bártolo, Paulo
A thermal-kinetic model, using the finite element method to study, simulate and optimise stereolithography, is presented in this paper. The model, which is theoretically rigorous and practical in its implementation, describes both the heat transfer effects and the course of the chemical reaction. This model includes the effects of photo-initiator concentration, temperature and light intensity, predicting the diffusion-controlled effects that occur after vitrification, the phenomenon of unimolecular termination and the shrinkage effects. Light intensity values at the resin surface are defined by assuming an appropriated Gaussian intensity distribution. The Beer-Lambert law enables to describe the decrease in light intensity with depth. The non-linear variation of the glass transition temperature with fractional conversion can be determined and consequently the mechanical behaviour of the resin sample predicted.
Interactions Between BMI and Age on Fall Risk in Older Adults
Publication . Rodrigues, Filipe; Monteiro, Diogo; Monteiro, A. M.; Forte, Pedro
Background/Objectives: The aging process is typically marked by a reduction in functional fitness, which heightens the likelihood of falling. Although obesity is established as a determinant of poor mobility, the interplay between excess weight and advanced age is still a topic of research interest. Therefore, this research investigated how age, sex, and Body Mass Index (BMI) interact to influence fall risk among older adults living in the community. Methods: This cross-sectional investigation involved 815 participants (Mage = 70.45 ± 6.10 years), stratified by age (sexagenarians, septuagenarians, octogenarians) and BMI (normal weight, overweight, obesity). Fall risk was assessed using the Timed Up and Go test. A Three-Way ANOVA examined the main and interaction effects. Results: No significant three-way interaction (p = 0.334) or main effect of sex (p = 0.079) was found. However, a significant age x BMI interaction was observed (p = 0.007). In sexagenarians and septuagenarians, obesity was associated with significantly slower fall risk performance compared to normal weight (p < 0.001). Conversely, in octogenarians, this difference was not significant (p = 1.000) with normal-weight individuals. Conclusions: Obesity may be a significant risk factor for falls, especially in adults aged 60 to 79 years. In octogenarians, the protective benefit of normal weight disappears, revealing a “weight paradox” likely driven by sarcopenia. Fall risk assessments and weight management strategies should be tailored to age, focusing on preserving muscle mass in octogenarians.
Body Image Satisfaction, Overweight Dissatisfaction, and Exercise Persistence: A Self-Determination Theory Approach
Publication . Salvador, Rogério; Naranjo, Lucio; Castuera, Ruth-Jiménez; Rebelo-Gonçalves, Ricardo; Monteiro, Diogo
Grounded in Self-Determination Theory (SDT), this study tested the hypothesis that body image perception delineates distinct motivational pathways, linking the perceived interpersonal style of exercise professionals to basic psychological needs, motivation quality, and long-term exercise persistence intentions. A sample of 821 regular exercisers was divided into two groups based on body image: “Satisfied” (n = 276) and “Dissatisfied due to Overweight” (n = 545). Participants completed validated measures of perceived interpersonal behaviors (supportive/thwarting), basic psychological need satisfaction/frustration, motivational regulation, and exercise persistence intention. A clear divergent pattern emerged, strongly supporting the main hypothesis. The “Satisfied” group reported a positive pathway: perceiving more need-supportive behaviors from instructors was associated with greater satisfaction of autonomy, competence, and relatedness, which in turn correlated with more self-determined motivation and stronger persistence intentions. Conversely, the “Dissatisfied” group reported a negative pathway: perceiving more need-thwarting behaviors was associated with greater need frustration, which correlated with more non-self-determined motivation and weaker persistence intentions. Measurement invariance confirmed these pathways are comparable across groups. The findings highlight that body image perception is a key correlate of distinct motivational experiences in exercise settings. Crucially, they underscore the significant association between the professional’s perceived interpersonal style and these pathways. Fostering need-supportive environments that enhance autonomy, competence, and relatedness is associated with more adaptive motivation and adherence, offering a valuable framework for practitioners aiming to support clients, particularly those with body image concerns.