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Contribuição para o Desenvolvimento de um Sistema Integrado de Exploração e Manutenção de Veículos Ferroviários
Full text linkAMBIT OF THE WORK The present work is inserted in SEM XXI 1 project, which case study is the Eurotram of Oporto. The goals are specially related to the development of a system of exploitation and maintenance of rail vehicles, based on the RAMS 2 methodology, working out of technical instructions manuals and maintenance manuals incident in the equipment’s life cycle cost. All the work here described was developed by a joint team of ADtranz 3 and MIIT 4 , in which the author is inserted, collaborating on the project’s engineering of the vehicle, as well as all the other departments involved on the Eurotram of Oporto’s project, for the validation of the developed work. The work team was organised by specialisation, at the image of the engineering of the vehicle’s project organisation, since it has clear advantages on the information flux and on the deep and equal responsibility of all the team members, in all the areas. However, the available data on the Eurotram of Oporto had been considered, initially, to have a preliminary character, so, the SEM XXI specialists' formation was made based on the available data of the Eurotram of Strasbourg, which is a vehicle with very similar characteristics. Each specialist was charged of the detailed research of the database of the ADtranz Group, in order to obtain all the available information on the systems under his responsibility. In relation to the author's activity during the development of the project, he was charged of several tasks, namely: • Complete study of the automatic coupler, namely, its structure, characterisation, functional and failure analysis, making up of the maintenance plans and work preparation, RAMS analysis and making up of maintenance and technical instructions manuals; • Cooperation on the manuals elaboration (maintenance and/or technical instructions) related to the Bogies, Video System, Passenger Information System and Pantograph; • Elaboration of the electronic catalogue of spare parts of all the vehicle’s systems; • Participation on the fulfilling of the technical specifications of special tools for the workshops; • Participation on the elaboration of the driver’s manual
Appreciating Relational Knowledge Management within the Queensland Music Festival : An Ethnographic Approach to Understanding Knowledge Management Practices
Full text linkEthical and Societal Challenges Facing Social and Educational Robots - Insights from the KASPAR Experience
No full textThis paper provides a comprehensive examination of theethical and societal challenges associated with the deployment of socialrobots in educational and therapeutic settings using the KASPARrobot as a practical example. Key ethical concerns explored include safeguardingone’s privacy, addressing the implications of robotic autonomy,and mitigating cybersecurity risks. Societal challenges such as the potentialdehumanisation of care practices, overreliance on robots, and theirlong-term impact on users’ social needs are analysed in depth. Drawingfrom empirical insights into children’s interactions with KASPAR,a social robot designed to operate as an educational tool in the contextof autism education, this paper discusses practical mitigation strategiesimplemented in KASPAR, emphasising transparency, human oversight,and multidisciplinary collaboration. The findings highlight the need forthoughtful integration of robotics in sensitive domains to balance innovationwith ethical responsibility
Investigation of static behavior of single-walled carbon nanotubes with helical axes: exact analytical solution
Full text linkThis study investigates the static behavior of single-walled carbon nanotubes (SWCNTs) with helical axes using Eringen’s nonlocal elasticity theory. The differential form of the nonlocal theory is employed to establish the relationship between local and nonlocal field variables within beam theory. These relationships are formulated in Frenet coordinates for a spatially curved beam model, yielding governing equations for helical SWCNTs with constant radius and uniform cross-section. Exact analytical solutions for the equations are obtained using the method of initial values, yielding closed-form solutions. Explicit expressions are provided for closed-coiled helical SWCNTs, representing the first exact analytical solution of Eringen’s differential nonlocal elasticity theory applied to helical nanostructures. A comprehensive parametric study is conducted to systematically analyze the effects of helix geometry (pitch angle, aspect ratio, winding angle) and nonlocal parameters on the static response. The results reveal that pitch angle and helix geometry strongly influence the coupling between normal, binormal, and tangential displacements. For small pitch angles, binormal displacement dominates, while larger pitch angles substantially increase normal and tangential displacements. The parametric studies establish clear relationships between geometric configuration, nonlocal length scale, and mechanical response, providing essential design guidelines for helical nanostructures in engineering applications
Malcolm Chase: a Roundtable Tribute
No full textThis paper brings together the reflections by three historians who knew Malcolm Chase, presented at the Northern History memorial conference in Leeds on 29 November 2024. It shows how integral Malcolm Chase’s work was to nineteenth-century political and labour history of Britain. It explains his impact and legacy on the study of history, especially in and of northern England, and ends with a call for more work on regional and working-class history
The effect of dietary interventions on brain-derived neurotrophic factor (BDNF) levels in adults: a systematic review of clinical trials
Full text linkBackground: Brain-derived neurotrophic factor (BDNF) is crucial for brain development, neuronal function, and metabolism. This systematic review aims to comprehensively examine the impact of various diets on BDNF levels, addressing gaps in understanding diet’s influence on BDNF’s role in neuroprotection and metabolism. Method: This systematic review was conducted in accordance with PRISMA 2020 guidelines. An extensive search was conducted in PubMed, Web of Science, and Scopus up to April 2024, using terms related to diet and BDNF. Relevant clinical trials involving adults were included. Data extraction covered study design, participant details, and outcomes, with quality assessed using the Cochrane method. Clarifications from authors were sought as needed to ensure comprehensive analysis. Results: This review examined 7633 articles to assess the impact of various diets on BDNF levels, narrowing down to 13 studies. The study found varying effects: intermittent fasting and ketogenic diets generally increased BDNF, while other diets showed minimal or no impact. The review highlights diverse outcomes and the need for further research on dietary effects on BDNF. Conclusion: The review found that fasting and calorie restriction diets generally increase BDNF levels, while other dietary interventions showed inconsistent effects. Further research is needed to better understand these dietary impacts on BDNF and to develop optimized strategies for enhancing cognitive health and managing obesity
A class of discrete memristive hyperchaotic maps with multi-cavity multi-structure attractors and its application in secure communication
Full text linkMemristors with nonlinearity and memorycharacteristics can effectively enhance chaotic dynamicscomplexity for chaotic maps. In this work, we present anovel discrete memristor model and couple it with sinemaps and iterative chaotic maps with infinite collapse(ICMIC) to construct a class of discrete memristive hyperchaoticmaps with multi-cavity multi-structure attractors.This class of multi-cavity multi-structure memristive sineICMIC modulation maps (MCMS-MSIMMs) possesses aninfinite variety of configurations, where the quantity andposition of coupled discrete memristors can be arbitrarilycombined. Numerical simulation results demonstrate thatthe sample map can exhibit hyperchaos, non-degeneracy,large-scale parameter control, multi-cavity attractors, multistructureattractors, and multi-cavity multi-structure attractors.The complexity and initial values of the system areexplored, revealing the high permutation entropy and initialoffset-boosting behavior. In addition, the FPGA-basedMCMS-MSIMM hardware circuit is designed, and the experimentalresults are consistent with the numerical results.Finally, MCMS-MSIMM is applied in secure communication,and the experimental results indicate that the proposedmap has better noise resistance performance compared toexisting maps
Control and energy management of standalone microgrids in remote areas: A review of recent advances, challenges, and opportunities for future research
Full text linkWhile standalone microgrids are an essential means of electrifying remote communities, high renewable penetration poses significant problems with power sharing, voltage/frequency stability, and optimal dispatch in low-inertia, communication-constrained scenarios. Using structured analysis across control methodologies, optimization techniques, and validation platforms, this paper synthesizes emerging paradigms in hierarchical control and energy management systems (EMS) through a systematic review of studies conducted in 2025. The following key findings show clear shifts: (i) adaptive droop and event-triggered consensus reduce communication overhead by 80% while maintaining voltage accuracy within ± 2%; (ii) super-twisting sliding mode control shows chattering-free operation with 98% cyber-attack detection capability; (iii) hybrid model predictive control frameworks enable real-time execution on embedded hardware with 25%–40% cost reduction; and (iv) deep reinforcement learning-based EMS shows 12% cost improvement and 97.8% reduction in computational load. There are still significant gaps: 68% of studies do not have hardware validation, 78% do not integrate cyber-security, power-sharing errors surpass 5% when there is an impedance mismatch, and there are no standardized benchmarking protocols. The review offers practical suggestions covering lifecycle-aware battery management, distributionally robust optimization (DRO) for renewable uncertainty, edge-computing architectures for communication-light operation, and cooperative cyber–physical testbeds for field validation. This synthesis provides a well-organized road map for developing technically demanding, financially feasible, and operationally robust microgrids that can provide sustainable access to electricity in underserved areas
Ketamine-related deaths registered in Scotland 2013-2024
Full text linkKetamine, a dissociative anaesthetic and non-competitive NMDA receptor antagonist, has legitimate medical applications. However, rising illicit use across the United Kingdom (UK) has been accompanied by growing reports of toxicity, dependence, and deaths. These have led to renewed policy discussions. Previous national studies have reported ketamine-related deaths elsewhere in the UK, but not in Scotland. This study examined all Scottish deaths (2013-2024) where ketamine was implicated, to provide a comprehensive evidence base for UK-wide policy discussions. Data were derived from anonymised National Records of Scotland records. All cases where ketamine was implicated in death were identified. Descriptive and comparative analyses were undertaken by year, sex, age, manner, and substances co-implicated. Less than one hundred deaths were registered during this period, and represented a very small proportion of all drug-poising deaths. There was a steady increase over time. Most decedents were male; the average age was the mid-30s. Most deaths were accidental and involved polysubstance use - typically opioids, stimulants, benzodiazepines, gabapentinoids, and alcohol. In most cases, acute drug use was the principal cause of death. The marked upward trend parallels that observed elsewhere in the UK. Polysubstance involvement, especially combinations of ketamine with opioids or benzodiazepines, substantially increases fatal risk through additive central nervous system depression. These findings reinforce the need for clearer public health messaging, targeted harm-reduction interventions, and careful monitoring of misuse, prescribing and diversion trends. Scottish ketamine-related deaths increased twentyfold in a decade. Most are preventable, highlighting the need for continued targeted education, intervention, and epidemiological monitoring
Evaluating public health campaigns on health promotion, substance use prevention and physical activity : a systematic review
Full text linkPublic health campaigns on substance use and physical activity aid disease prevention. This review examines how process evaluations are conducted in substance use and physical activity campaigns, focusing on methodologies, theoretical frameworks, implementation quality, fidelity, reach, and delivery. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a comprehensive literature search was conducted across PubMed, PsycINFO, Web of Science, Scopus, ProQuest, and Google Scholar from 1990 up to April 2025. Eligible studies included randomized controlled trials, quasi-experimental, and observational designs involving adult human participants and reporting process or implementation evaluation components. Twenty-one studies met inclusion criteria. A one-step forward citation analysis was performed using the bibliometrix package in R. Findings revealed that 62% of studies reported process evaluation components, with 52% employing mixed-method approaches. Commonly cited theoretical frameworks included the Transtheoretical Model, Theory of Planned Behaviour, and Social Cognitive Theory. Only 20% of studies explicitly defined process evaluation objectives, and few translated findings into actionable implementation adaptations. Bibliometric analysis indicated influence across 373 publications, primarily from the United States, Australia, and Canada. Overall, process evaluation in public health campaigns remain inconsistent. To enhance the quality and utility of such evaluations, greater theoretical integration, improved methodological transparency, and the use of standardized assessment tools are recommended