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Riscos associados à aplicação de betão projetado – Mina de Aljustrel
No full textA exploração de minério, dentre todas as atividades da indústria extrativa, é reconhecida como uma atividade de alto risco, sujeita a legislação específica. O principal objetivo desta dissertação é desenvolver um instrumento de avaliação de riscos adaptado à indústria extrativa, visando minimizar a subjetividade nos critérios de avaliação.
Os objetivos centrais do estudo são acompanhar e verificar a correta execução do processo construtivo em obras, com foco especial na aplicação de betão projetado em galerias de mina subterrânea, priorizando a prevenção de riscos na perspetiva da segurança e saúde no trabalho. O estudo também procura compreender a correlação entre risco e trabalhadores, equipamentos e indicadores utilizados, visando otimizar a redução de acidentes de trabalho.
A avaliação de risco desempenha um papel crucial na prevenção de acidentes e na proteção da integridade física dos trabalhadores, utilizando-se neste trabalho a Matriz GUT. A identificação das condições de segurança e saúde ligadas ao processo produtivo permite uma avaliação detalhada de todas as tarefas, métodos de execução, tipos de equipamentos/materiais utilizados, número de pessoas expostas, perigos, eventos desencadeadores e riscos ocupacionais.
Embora a eliminação completa de todos os perigos e eventos desencadeadores nem sempre seja viável, medidas de controle e prevenção podem significativamente reduzir a exposição dos trabalhadores aos riscos, melhorando as condições de segurança e trabalho. Nesse contexto, o foco principal desta dissertação foi identificar o processo executivo da aplicação de betão projetado na mina subterrânea de Aljustrel, Portugal, juntamente com os seus subprocessos.
Metodologicamente, foi realizado um estudo descritivo de natureza transversal. Os dados recolhidos foram inseridos no programa estatístico Statistical Package for the Social Science (SPSS), seguido por uma análise estatística para atender aos objetivos do estudo.
Por fim, recomenda-se que novas pesquisas aprofundem a análise dos impactos das medidas implementadas ao longo do tempo, avaliando sua efetividade na redução de acidentes e na melhoria das condições de trabalho na indústria extrativa.Mining, among all the activities in the extractive industry, is recognized as a high-risk activity, subject to specific legislation. The main aim of this dissertation is to develop a risk assessment tool adapted to the extractive industry, with a view to minimizing subjectivity in the assessment criteria.
The central objectives of the study are to monitor and verify the correct execution of the construction process on construction sites, with a special focus on the application of shotcrete in underground mine galleries, prioritizing risk prevention from the perspective of occupational health and safety. The study also seeks to understand the correlation between risk and the workers, equipment and indicators used, with a view to optimizing the reduction of accidents at work.
Risk assessment plays a crucial role in preventing accidents and protecting the physical integrity of workers, using the GUT Matrix in this study. Identifying the health and safety conditions linked to the production process enables a detailed assessment of all tasks, methods of execution, types of equipment/materials used, number of people exposed, hazards, triggering events and occupational risks.
Although the complete elimination of all hazards and triggering events is not always feasible, control and prevention measures can significantly reduce workers' exposure to risks, improving safety and working conditions. In this context, the focus of this dissertation was to identify the executive process of applying shotcrete in the Aljustrel – Portugal, underground mine, along with its sub-processes.
Methodologically, a descriptive cross-sectional study was conducted. The data collected was entered into the Statistical Package for the Social Science (SPSS) statistical program, followed by a statistical analysis to meet the study's objectives.
Finally, it is recommended that further research deepens the analysis of the impacts of innovative measures over time, evaluating their effectiveness in reducing accidents and improving working conditions in the extractive industry
Prehistoric castles in the Lower Tagus and Atlantic Coast: consequences of economic intensification and social competition in the 3rd millennium BC
No full textIn Estremadura, there are three major Chalcolithic fortified settlements, which are also those that have been studied for the longest time. Although they adopted common architectural solutions, they evolved independently, starting with the need to adapt to the natural geomorphological conditions prevailing in each case.
Leceia, Zambujal and Vila Nova de São Pedro are clear examples of how, in Lower Estremadura, during the Chalcolithic, the traditional concepts of “fortification”, “interaction” and “economic intensification” were strongly interdependent: although there could be interaction and economic intensification without fortification, the reverse does not seem possible for the period and region in question, as clearly is provd by the archaeological evidence
Healthy school, healthy teachers: mediating effect of optimism
No full textIn recent years, the relationship between teachers’ health and organizational health in schools has attracted growing interest in educational research. The studies by Borralho et al. (2020) and Bagdziuniene et al. (2023) indicate that a positive organizational environment—characterized by a supportive climate, effective leadership, and strong interpersonal relationships—has a significant impact on teachers’ physical and mental health, influencing aspects such as professional wellbeing, exhaustion, cognitive disorders, musculoskeletal issues, and voice alterations. Research also highlights that fostering a positive organizational culture through interventions aimed at improving teachers’ well-being can lead to enhanced job satisfaction and resilience, ultimately benefiting both educators and students (Van Woerkom, 2021)
Design optimisation of five pilot-scale two-stage vertical flow-constructed wetlands for piggery wastewater treatment
No full textWith growing pig farming, sustainable piggery wastewater treatment methods are essential for environmental protection. This study evaluated five pilot-scale two-stage vertical flow-constructed wetlands (VFCWs) with varying configurations of aeration, plantation, and saturation zones. Three VFCW configurations (1VFCW, 2VFCW, and 3VFCW) were unsaturated, while 4VFCW and 5VFCW were saturated in the second stage (up to 60 and 90 cm, respectively). The 5VFCW featured a stacked configuration with no space between its two stages. Passive aeration was selectively applied in 2VFCW, 3VFCW, 4VFCW, and 5VFCW, while plants were present in most configurations except the control. Saturated 4VFCW achieved the highest removal efficiency for TN (77.03 + 16.24%) and NO3 (46.06 + 45.96%), while the stacked 5VFCW showed the highest removal for chemical oxygen demand (COD) (94.17 + 4.85%) and total ammoniacal nitrogen (TOC) (86.35 + 6.78%). Unsaturated 1VFCW excelled in TAN removal (98.89 + 0.33%), and the control system (C) showed the highest removal efficiency for PO4 3 (90.38 + 6.52%) and TOC (87.52 + 9.83%). Overall, 4VFCW emerged as the most balanced and effective system, supported by an optimal combination of aerobic and anaerobic conditions that facilitated sequential nitrification and denitrification, along with an extended hydraulic retention time due to saturation
Multinational attitudes toward AI in Health Care and diagnostics among Hospital patients.
No full textThe successful implementation of artificial intelligence (AI) in health care depends on its acceptance by key stakeholders, particularly patients, who are the primary beneficiaries of AI-driven outcomes. OBJECTIVES To survey hospital patients to investigate their trust, concerns, and preferences toward the use of AI in health care and diagnostics and to assess the sociodemographic factors associated with patient attitudes. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study developed and implemented an anonymous quantitative survey between February 1 and November 1, 2023, using a nonprobability sample at 74 hospitals in 43 countries. Participants included hospital patients 18 years of age or older who agreed with voluntary participation in the survey presented in 1 of 26 languages. EXPOSURE Information sheets and paper surveys handed out by hospital staff and posted in conspicuous hospital locations. MAIN OUTCOMES AND MEASURES The primary outcome was participant responses to a 26-item instrument containing a general data section (8 items) and 3 dimensions (trust in AI, AI and diagnosis, preferences and concerns toward AI) with 6 items each. Subgroup analyses used cumulative link mixed and binary mixed-effects models
Literacia mediática: O caso do Clero Católico em Portugal
No full textNum tempo de profundas alterações tecnológicas e digitais, as redes sociais substituíram o espaço público tradicional e ganharam nova relevância. Por isso, também nesta área é importante que a Igreja Católica saiba ler os “sinais dos tempos”. Por nos parecer uma reexão relevante, o 7MARGENS publica este texto sobre a utilização das redes sociais pelo clero português, que resulta de um trabalho coletivo tendo por base um outro artigo já publicado pelos autores, aos quais agradecemos a disponibilidade para publicar esta versão.N/
Condition and mortality rates of deep-sea elasmobranchs from crustacean bottom trawl fisheries in the southern Portugal
No full textO mar profundo compõe 90% dos oceanos e apesar de ainda muito desconhecido apresenta uma elevada biodiversidade, sendo extremamente vulnerável às ações antropogénicas, como a pesca de arrasto de fundo, especialmente para crustáceos. Esta prática apresenta altas taxas de capturas acessórias, incluindo elasmobrânquios de profundidade, que são particularmente sensíveis devido seu complexo ciclo de vida. Embora representem uma parte significativa das capturas acessórias nos arrastões de crustáceos, pouco se sabe sobre os impactos desta atividade e a biologia e ecologia destas espécies. Este estudo propôs-se a preencher algumas lacunas no conhecimento a este propósito, com base na avaliação de 1.559 espécimens pertencentes a 18 espécies de elasmobrânquios de profundidade nas costas Sul e Sudoeste de Portugal. Os resultados mostraram que estas espécies contribuem significativamente para as taxas de capturas acessórias, chegando a representar até 60% do peso total capturado em profundidades superiores às permitidas (> 800 m). Além disso, apresentaram elevados níveis de stress e mortalidade a bordo, com 95% dos espécimens encontrados mortos ou a morrer. A sobreposição das zonas de alimentação dos elasmobrânquios com áreas de pesca pode justificar estas elevadas taxas de captura, pois as espécies mais abundantes alimentam-se de diversas presas, bem como de crustáceos alvos desta pescaria. Importantes observações para a gestão pesqueira são apresentadas a destacar a necessidade de implementar medidas eficazes de monitorização e mitigação dos impactos. Para tal, foi desenvolvido um sistema de monitorização eletrónica que permitiu a identificação remota dos espécimens capturados. Além disso, foi criado um protocolo de boas práticas para o manuseamento de elasmobrânquios a bordo dos arrastões. Os resultados ampliam o conhecimento destas espécies e fornecem uma base sólida para políticas rigorosas, essenciais à conservação e à gestão sustentável das pescarias e das populações destes animais.The deep-sea comprises 90% of the oceans and, despite being largely unexplored, harbours high biodiversity and is extremely vulnerable to anthropogenic activities, such as bottom trawl fishing, particularly for crustaceans. This practice results in high bycatch rates, including deep-sea elasmobranchs, which are markedly sensitive due to their complex life cycles. Although these species constitute a significant portion of bycatch in crustacean trawling, little is known about the impacts of this activity and the biology and ecology of these species. This study aimed to address some of these knowledge gaps by evaluating 1,559 specimens from 18 deep-sea elasmobranch species off the South and Southwest coasts of Portugal. Results showed that these species significantly contribute to bycatch rates, representing up to 60% of the total catch weight at depths exceeding the legal limit (>800 m). Additionally, high levels of stress and onboard mortality were observed, with 95% of specimens found dead or dying. The overlap between elasmobranch foraging areas and fishing zones likely explains these high capture rates, as the most abundant species feed on various prey, including the target crustaceans of this fishery. Key observations for fisheries management are presented, highlighting the urgent need to implement effective monitoring and mitigation measures. To this end, an electronic monitoring system was developed, enabling the remote identification of captured specimens. Furthermore, a best-practices protocol for handling elasmobranchs onboard trawlers was established. The findings expand the knowledge of these species and provide a solid foundation for stringent policies essential for the conservation and sustainable management of fisheries and elasmobranch populations
Comparison of different microalgae biomass typologies used in rotifers enrichment for zebrafish (Danio rerio) larvae nutrition
No full textThe use of enriched rotifers with industrially produced microalgae represents a valuable tool for the enhancement of zebrafishlarval nutrition and increased biological performance. Currently, a monoculture of microalgal species (Nannochloropsis sp.) inform of liquid paste is routinely used for rotifers enrichment for zebrafish larvae feeding; however, the most adequate typology (i.e.,paste or freeze-dried) of the industrially produced microalgal biomass is still controversial. This work aimed to compare the effectsof rotifers enriched with three different industrially produced microalgae species (i.e., Nannochloropsis oceanica, Tetraselmis chui,and Tisochrysis lutea) using paste and freeze-dried powder. Enriched rotifers were provided as feed during larval growth and theimpact on growth and survival was evaluated. The use of enriched rotifers with both paste or freeze-dried microalgae improvedgrowth compared to larvae fed exclusively with commercial microdiet. Larvae fed rotifers enriched with N. oceanica and T. chuiattained higher weight and length both at 15 and 30 days postfertilization (dpf ), while the use of microalgae in paste contributed togreater larvae lengths when compared to freeze-dried. The experimental results in this study revealed that N. oceanica and T. chuiin paste are the most suitable microalgae forms to be used in zebrafish larvae nutrition and in the improvement of enrichmentmethodologies for rotifers.31/SI/2017/39896; 2022.10077.BDAN
O papel moderador dos estilos de vinculação e da vergonha interiorizada na relação entre disponibilidade emocional parental e o abuso de substâncias
No full textO consumo de substâncias psicoativas tem um grande impacto na saúde geral da população, como tal, é necessário compreender de uma forma mais abrangente este comportamento, para que seja possível prevenir e intervir. Este estudo pretende investigar a existência de uma relação entre a disponibilidade emocional percecionada com os consumos, como também, averiguar se os estilos de vinculação nas relações interpessoais e a vergonha internalizada são fatores de risco para o aumento dos mesmos. Para tal, 231 participantes responderam a questionários sobre a disponibilidade emocional percecionada, vergonha internalizada, estilos de vinculação, e motivos para os consumos. Os resultados refletem correlações estatisticamente significativas positivas entre as variáveis disponibilidade emocional dos pais percecionada e estilos de vinculação mais confiantes e confortáveis. Por outro lado, também foi possível observar correlações estatisticamente significativas negativas entre a disponibilidade emocional dos pais percecionada, vergonha internalizada, estilos de vinculação ansiosos e motivos para o consumo de substâncias. Estes resultados sugerem que quanto menos disponibilidade emocional percecionada mais estratégias de coping mal adaptativas irão ser desenvolvidas pelo individuo, e este terá uma maior predisposição para recorrer aos consumos como forma de aliviar sofrimento psíquico.Substance use has a big impact in the general health of the population, so, it is important to understand this behavior in a more holistic way in order to prevent and realize interventions more efficient. This study aims to investigate a relation between the perception of emotional availability and the substance use, as well as the impact of attachment styles in interpersonal relationship and internalized shame as risk factors for the development of substance use disorder. In order to do that, 231 participants answered an on-line questioner about emotional availability, internalized shame and attachment styles. The results reflect a statistically significant and positive relationship between emotional availability and secure attachment styles. But also, a statistically significant and negative relation between emotional availability, internalized shame, anxious attachment styles and motives for substance misuse. These results suggest that lowers levels of emotional availability precepted are associated with maladaptive coping strategies, and will lead the individual to use substances as a way of release psychic suffering
Complex societies of the 3rd millennium BC and the bellbeaker question
No full textIn the 150 years following the collection of the first fragments of bell-beaker ceramics in Portuguese territory, few studies were presented on these manifestations, with emphasis on those produced by Octávio da Veiga Ferreira (1966) and Richard J. Harrison (1977). The Author also produced several studies on this subject, which became increasingly complex as the data accumulated, This short essay corresponds to an updated synthesis on this very discussed topic, which is of interest to the entire European continent