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- Understanding the influence of transfusion and blood loss on tranexamic acid concentration in scoliosis surgery with blood lossPublication . Sá, Paula Alexandra; Barreiros, Luísa; Segundo, Marcela A.; Cruz, Eugénia; Langenecker, Sibylle; Barreiros, LuisaTranexamic acid (TXA) stabilizes clot formation by inhibiting fibrin degradation and improves postoperative outcomes. However, rare adverse events (e.g., thrombosis, seizures) warrant dose–risk evaluation. This study examines how perioperative blood loss and transfusion practices affect TXA concentrations during paediatric scoliosis surgery. Forty-three patients undergoing scoliosis surgery with TXA were retrospectively analysed. The study assessed the impact of packed red blood cell (PRBC) transfusion on plasma TXA levels and whether maintaining concentrations ≥10 μg/ mL correlated with intraoperative blood loss. TXA levels were measured using UHPLC–MS/MS. Results: Median TXA concentration 30 min after the loading dose was 37.8 μg/mL (IQR: 31.4–39.6 μg/mL), decreasing to 10.6 μg/mL (IQR: 9.7–13.5 μg/mL) after transfusion. At surgery end, the mean concentration was 12.9 ± 2.5 μg/mL. Thirty-one patients maintained TXA levels ≥10 μg/mL, associated with 80% inhibition of tissue plasminogen activator. Of six patients below this threshold, five had received transfusions. A significant correlation was found between higher intraoperative blood loss and lower TXA levels, consistent with a dilutional effect. In contrast, among patients with TXA ≥ 10 μg/mL, correlation with blood loss was weak (Spearman's ρ = 0.11, p = 0.54). Findings suggest homologous PRBC transfusion reduces plasma TXA through volume expansion. Sustaining TXA concentrations >10 μg/mL is essential for antifibrinolytic efficacy and haemostatic outcomes. The dilutional impact of PRBC transfusion underscores the need for intraoperative dose adjustment. Optimizing TXA dosing requires understanding pharmacokinetics and patient variability.
- Comunicação, Inclusão e Qualidade Caminhos Colaborativos para a EducaçãoPublication . Gonçalves, Sofia; Chambel, Clara; Pires, João; Castro, Maria Cristina; Martins, Fernando; Brito-Costa, Sónia; Gonçalves, SofiaEste livro, intitulado “Comunicação, Inclusão e Qualidade: Construção Colaborativa de Trajetórias Educativas”, reúne reflexões e propostas que abordam, de forma didática, pedagógica e sistemática, três dimensões centrais para o desenvolvimento das organizações escolares: a comunicação organizacional, a inclusão sociocultural e a qualidade educativa. Os capítulos que integram esta obra apresentam contributos práticos e teóricos que permitem compreender como a comunicação eficaz pode potenciar a cultura organizacional, como a diversidade cultural e a inclusão desafiam e enriquecem os contextos escolares, e de que forma a qualidade no ensino profissional pode ser fortalecida a partir da articulação entre quadros europeus e práticas internas. O caráter científico-aplicado da obra resulta da investigação-ação levada a cabo pelos autores, em contextos educativos concretos, onde a teoria e a prática se encontram de forma crítica e transformadora. Este e-book assume uma natureza interdisciplinar e colaborativa, constituindo-se como um recurso para a formação de profissionais qualificados e como estímulo à reflexão crítica sobre os caminhos possíveis para a construção de organizações escolares mais inclusivas, comunicativas e orientadas para a qualidade.
- Aumento do rendimento de blocos numa linha de laminagem de blocos de cortiça com borrachaPublication . ALUAI, ISABEL SOFIA PINTO PINHAL; Campilho, Raul Duarte Salgueiral GomesA indústria dos compósitos de cortiça e borracha representa um setor de elevado valor no mercado. No entanto, a natureza heterogénea da cortiça impõe desafios constantes à estabilidade dos processos produtivos, particularmente no que toca à estabilidade dimensional e à integridade estrutural dos blocos produzidos. No contexto atual de competitividade global, a transição de métodos de produção tradicionais para sistemas baseados em dados e monitorização em tempo real deixou de ser uma opção para se tornar uma necessidade num contexto industrial. Pequenas variações na altura útil dos blocos podem representar perdas financeiras massivas quando escaladas para volumes de produção industrial. Da mesma forma, a não conformidade dos blocos não é apenas um defeito visual, mas um compromisso no desempenho técnico do material. A presente dissertação tem como objetivo a otimização da linha de transformação de blocos de cortiça com borracha, foram abordados problemas críticos de rendimento dimensional e porosidade. O objetivo central foi estabilizar a altura útil dos blocos acima dos 150 mm e reduzir as taxas de rejeição qualitativa. A metodologia integrou a implementação de um sensor a laser para a monitorização em tempo real da altura na aglomeração, um novo protocolo de limpeza técnica dos moldes e a otimização da lógica do calcador no PLC. Para garantir a rastreabilidade e integridade dos dados, foi desenvolvida uma aplicação em Power Apps, o que permitiu um registo digital de pesos e medidas com integração em dashboards de Power Bi. Os resultados demonstram uma recuperação dimensional de 9 mm e 8 mm nas referências de maior volume e ganhos monetários consideráveis. Paralelamente, a taxa de porosidade na referência que é produzida em maior quantidade foi reduzida de 1,90% para 0,50%. Estes avanços traduziramse numa melhoria significativa da eficiência global (OEE), que evoluiu de um estado inicial de 41,94% para 52,55%. O projeto culminou na transição para um modelo de gestão baseada em dados (data-driven), é maximizada a rentabilidade operacional e são consolidados os pilares da Indústria 4.0 no chão de fábrica.
- A comprehensive profile of volunteer firefighters: sociodemographic and occupational dimensionsPublication . Teixeira, Tatiana; Carvalho, Eduardo; Santos, Joana; Vaz, Mário; Guedes, Joana; Santos, JoanaThe European Union prioritizes occupational health and safety, with firefighters—particularly volunteers—facing significant risks. In Portugal, 94% of firefighters are volunteers, often balancing multiple jobs, which increases their exposure to hazards. This study investigates Portuguese firefighters’ occupational risks and identifies tasks with the highest accident incidence to build a comprehensive profile of their health and work conditions. Firefighters are exposed to extreme environments, long shifts, and high-stress situations, especially during wildfires. These conditions contribute to physical and mental health issues, including cardiovascular disease and sleep disturbances. Training and experience are key to improving risk perception and preventing accidents. Understanding firefighters’ main characteristics is essential for risk reduction and improving their quality of life. A sociodemographic questionnaire was developed and administered to firefighters, covering three sections: General Information, Lifestyle and Clinical History, and Firefighting Activity. This enabled the collection of sociodemographic and occupational data. A total of 220 responses were collected from Portuguese volunteer firefighters. Cardiovascular and respiratory diseases were the most commonly reported diagnoses. Wildland and urban/industrial fires were the main operational contexts linked to accidents, with 84 individuals reporting accident history in these scenarios. The study revealed a lack of data on the profile of volunteer firefighters, a group at heightened risk due to cumulative exposures and existing health conditions. Further research is needed to support the development of regulations and health monitoring strategies that protect this workforce without compromising their operational capacity.
- Are wearable sleep-tracking devices reliable alternatives to Polysomnography? A Systematic Review and Meta-AnalysisPublication . Agostinho, Margarida; Borges, Maria; Pereira, Telmo; Borges, Daniel Filipe; Soares, Joana Isabel; Borges, Daniel FilipePolysomnography (PSG) is the reference method for characterizing sleep architecture, but it is resource-intensive and difficult to scale for large cohort assess ments. This has increased interest in wearable devices for naturalistic sleep monitoring. This systematic review and meta-analysis evaluated how wearable sleep-tracking devices compare with laboratory PSG in healthy adults across standard sleep metrics and sleep stage durations. PubMed, Scopus, Scielo, Web of Science, and the Cochrane Library were searched following PRISMA guidelines. Eligible studies included healthy adults under going simultaneous wearable and PSG recordings. Mean differences were synthesized for total sleep time, sleep latency, sleep efficiency, wake after sleep onset, and time spent in light (N1+N2), deep (N3), and REM sleep using fixed or random effects models based on heterogeneity, with significance set at p < .01. Risk of bias and applicability were assessed using QUADAS-2. Sixteen studies met the inclusion criteria, and ten contributed to the meta- analysis. Wearable devices overestimated total sleep time and sleep efficiency and underestimated wake after sleep onset, with substantial variability between devices. No device demonstrated consistently superior performance. In individual studies, the closest agreement with PSG was observed for the Oura Ring (third generation) for sleep latency and sleep efficiency, and for selected Fitbit models for deep and REM sleep. Wearable devices provide reasonable estimates of global sleep metrics and may complement PSG for population monitoring and longitudinal self-tracking. However, variable performance, methodological heterogeneity, and risk-of-bias consid erations currently limit their use as stand-alone diagnostic tools or for detailed sleep- stage characterization.
- Lichen extracts containing volatile compounds induce oxidative stress and modulate the growth of Microcystis aeruginosa and Chlorella sorokinianaPublication . Essadki, Yasser; Darrag, El Mehdi; Zerrifi, Soukaina El Amrani; Haida, Mohamed; Krimech, Aafaf; Martins, Rosário; Campos, Alexandre; Vasconcelos, Vitor; Bouaïcha, Noureddine; Baçaoui, Abdelaziz; Meddich, Abdelilah; Oudra, Brahim; Tazart, Zakaria; El Khallouf, Fatima; Martins, RosarioThis study evaluates volatile extracts (HE1 and HE2) from the lichen Pseudevernia furfuracea as eco-friendly agents to control algal proliferation, specifically targeting the cyanobacterium Microcystis aeruginosa and the green microalga Chlorella sorokiniana. Both extracts exhibited potent anti-microalgal activity against the two species with a minimum inhibitory concentration (MIC) ranging from 375 to 750 µg/mL. Furthermore, both extracts reduced cell density by more than 98% after eight days of treatment. Chlorophyll a and protein levels decreased significantly (>80%) in both species, indicating suppression of pigment synthesis. However, their physiological responses were distinct: M. aeruginosa underwent early acute oxidative stress and severe membrane damage, while C. sorokiniana exhibited delayed oxidative activation and a negative growth rate, suggesting non-lytic metabolic inhibition. An in silico study by molecular docking of the most abundant compounds identified in these volatile extracts, such as terpenoids (abietatriene, δ-cadinene) and a phenolic compound (atraric acid), showed that these compounds interact with vital cellular targets in M. aeruginosa and C. sorokiniana and likely contribute to the effects observed in these two species. Predictive toxicity by applying the ADMET framework confirmed the favorable bioavailability and low acute toxicity of these volatile compounds. Therefore, P. furfuracea volatiles are promising, species-specific, and environmentally safe candidates for mitigating aquatic algal proliferation through targeted oxidative and metabolic interference.