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Despite the wide use of Drucker-Prager plasticity-based models on polymers, the experimental measurement of the dilation angle, a critical parameter to fully describe the plastic potential, has been rarely reported in existing literature. This paper shows, for the first time, the experimental characterisation of the dilation angle of polymers over a wide range of plastic strain. These measurements were obtained from uniaxial compression experiments conducted on poly(methyl methacrylate) (PMMA) and an untoughened epoxy resin. The calculation of the dilation angle relied on the measurements of the compressive force and the strain components obtained via Digital Image Correlation (DIC). Lower values of dilation angle were obtained for the epoxy resin, suggesting that resistance to volumetric change during plastic deformation could be associated to molecular structure and internal forces. The methodology and results presented in this study can be applied to different types of materials and employed for developing and validating constitutive models that incorporate plastic dilation.

Currently, the useable compressive properties of a composite are restricted by set design limits well below the expected intrinsic performance of the materials contained within. The next generation of high-performance fibre-reinforced polymer composites will need to address the challenge of improving the absolute performance of composites in compression. This task requires a rethink of the whole system; not only to address practical limitations of current materials, but their combination, interface, and their architecture. The mechanisms involved do not simply act over the nano-, macro-, or meso-level independently, but are mutually related at the system level, complicating the approach.

This study aims to develop and implement actual carbon fibre-reinforced polymer (CFRP) solutions for realising structural fuses in real components. To this end, we have developed various concepts for structural fuses, applied to generic idealised components and aimed at engaging different in-plane and through-the-thickness damage propagation mechanisms. Micro-cut patterns (MCPs) / crack path combinations have been engraved on thin-ply CFRP prepregs (by using a laser cut machine) for manufacturing CFRP specimens. Afterwards, we have carried out a series of experimental studies to evaluate the fracture properties of various MCPs under three-point bending (3PB). Then, 3PB results were used to refine and down-select our concepts, for use in our generic idealised component design to test them under indentation test using a cantilever beam rig. The test results demonstrated that MCPs can provide significant control over the fracture locus and path, additionally allowing the failure initiation load and energy dissipation to be tailored.

Introduction: Persistent respiratory symptoms at rest and during exertion (e.g., dyspnea, fatigue) play a role on the low physical activity (PA) levels found in people with chronic obstructive pulmonary disease (COPD), but other factors may also be involved. Environmental factors have been shown to impact PA levels in other patient populations, but evidence regarding people with COPD is still scarce. Investigations have been focused mostly on outdoor factors, such as air pollution or population density, disregarding the patients’ perception of their surroundings, both indoor and outdoor milieus. Objectives: This study explored the relationship between self-reported indoor and outdoor physical environmental opportunities for PA and actual PA levels in patients with COPD. Methods: Patients with COPD completed the Physical Activity Neighbourhood Environment Survey (PANES; total score 0-6, higher scores indicating a more supportive PA environment; 11 subscales: Residential Density, Land Use Mix, Access to Transportation, Infrastructure for Pedestrians, Infrastructure for Bicycles, Recreation Facilities, Street Connectivity, Security – Crimes, Security – Traffic, Security – Pedestrians, Aesthetics) and questions regarding their indoor and outdoor home environment (car ownership; having a dog, corridor, elevator, stairs and/or exercise equipment). An accelerometer was used for 7 days to assess daily PA: steps (steps/day); time in moderate and vigorous PA (MVPA; min/day); total PA (TPA; light PA+MVPA; min/day). Mann-Whitney-U and Spearman’s correlations (r) tests were conducted. Results: Ninety-four patients [78 males (83%), 67 ± 8 years, 48 ± 19 FEV1% predicted] participated in this study. PANES total score (n = 75) was 3 [1;4] (median [Q1;Q3]). Forty-three patients had a dog (13 walked it regularly); 63 had stairs, 12 had an elevator, 71 had a corridor, 45 had exercise equipment (stationary bicycle, n = 21) and 84 owned a car. Participants performed 4,428 [2,761;6,886] steps/ day, 19 [9;41] min/day of MVPA and 144 [103;208] min/day of TPA. Patients walking the dog presented a significantly higher daily step count (4,895 [2,644;7,780] vs. 4,422 [2,850;6,775] steps/day, p = 0.01) and time in TPA (154 [100;256] vs. 144 [103;177] min/day, p =.03) than those not walking the dog. No other significant differences were observed in the indoor and outdoor home environment (p > 0.05). No significant correlations were found between any of the PANES subscales and the different PA outcomes (-0.210 ≤ r ≤ 0.181, p > 0.05). Conclusions: A minimal influence of neighbourhood environmental factors on PA levels of patients with COPD was found in this observational study. Findings support previous research, as walking the dog impacted patients’ daily step counts. Longitudinal research is needed to more definitely evaluate potential environmental opportunities to promote PA in people with COPD. published

RESUMO Introdução A Larva Migrans Cutânea é uma dermatose infeciosa provocada por parasitas nematoides que infestam o Homem de forma acidental. É uma doença endémica em países tropicais, sendo o diagnóstico pouco comum nos países industrializados. Os autores apresentam o caso clínico de um trabalhador infetado durante uma viagem laboral ao Brasil, tendo como objetivo alertar os trabalhadores que viajam para destinos laborais com praias e climas tropicais sobre o risco de infestação por esta larva e as respetivas medidas preventivas. Descrição do Caso Clínico Os autores descrevem o caso de um homem de 32 anos, regressado de uma viagem em trabalho a zona endémica, com lesões pruriginosas, serpiginosas típicas na região plantar do pé direito. Teve evolução favorável com terapêutica oral com Albendazol. Faz-se uma revisão da epidemiologia, manifestações clínicas e opções terapêuticas. Discussão/Conclusão As crescentes viagens de lazer, mas sobretudo de trabalho, no contexto português, para as zonas endémicas, obrigam o profissional de saúde, sobretudo o Médico do Trabalho, a estar apto a diagnosticar patologias que cada vez mais deixarão de ser raridades.

RESUMO Introdução A COVID-19 é uma infeção respiratória causada pelo coronavírus SARS-CoV-2, de elevada transmissibilidade e de distribuição global. Apesar de precoces, os dados atuais apontam para a capacidade do SARS-CoV-2 atingir o sistema nervoso central, periférico e até mesmo o músculo. Descrição do Caso Clínico Este caso diz respeito a uma profissional de saúde, 31 anos de idade, em contacto diário com doentes COVID-19. Recorreu ao Serviço de Urgência, por alteração da sensibilidade da hemiface direita e assimetria facial, tendo tido alta medicada e sendo assumido o diagnóstico de Paralisia de Bell. Cerca de uma semana após este episódio, recorre novamente por mal-estar geral, febre, náuseas e vómitos, procedendo-se ao despiste de COVID-19, que se revelou positivo. Discussão/Conclusão O relato deste caso apoia a hipótese da paralisia do nervo facial como uma possível manifestação neurológica devido à infeção por COVID-19. Reforça também a importância de exame físico cuidado e historial médico detalhado, evitando atrasos no diagnóstico e consequentemente a transmissibilidade do vírus.

RESUMO Introdução: O ruído é um dos mais importantes poluentes ambientais e o seu impacto na saúde tem vindo a ser cada vez mais reconhecido. Além dos seus efeitos no sistema auditivo, o ruído afeta vários outros órgãos e sistemas. Objectivo: Nesta revisão pretendemos conhecer o impacto do ruído a nível extra-auditivo, bem como identificar medidas preventivas, de forma a minimizar os seus efeitos nocivos. Material e métodos: Trata-se de uma Scoping Review realizada através de uma pesquisa nas bases de dados PUBMED e MEDLINE, entre os meses de janeiro e março de 2021. As palavras-chave utilizadas foram ‘noise’, ‘sleep disturbance’, ‘cardiovascular diseases’, ‘metabolic diseases’, ‘cancer’ e ‘hospital noise’. Resultados: Foi demonstrado que o ruído está relacionado com perturbações do sono, doenças cardiovasculares, doenças metabólicas e neoplasias; afetando também a nível hospitalar o desempenho dos profissionais de saúde. Conclusão: Os efeitos extra-auditivos do ruído são variados, assumindo-se como um problema de saúde pública que exige medidas de controlo e de prevenção, de forma a limitar a tendência crescente das suas consequências negativas, quer a nível de saúde, quer a nível económico.

The open science movement has developed out of growing concerns over the scientific standard of published academic research and a perception that science is in crisis (the "replication crisis"). Bullying research sits within this scientific family and without taking a full part in discussions risks falling behind. Open science practices can inform and support a range of research goals while increasing the transparency and trustworthiness of the research process. In this paper, we aim to explain the relevance of open science for bullying research and discuss some of the questionable research practices which challenge the replicability and integrity of research. We also consider how open science practices can be of benefit to research on school bullying. In doing so, we discuss how open science practices, such as pre-registration, can be of benefit to a range of methodologies including quantitative and qualitative research and studies employing a participatory research methods approach. To support researchers in adopting more open practices, we also highlight a range of relevant resources and set out a series of recommendations to the bullying research community.