DSpace Collection:
http://hdl.handle.net/10174/29513
2024-03-28T09:29:08ZChemical stability of new nafion membranes doped with bisphosphonic acids under Fenton oxidative conditions
http://hdl.handle.net/10174/36202
Title: Chemical stability of new nafion membranes doped with bisphosphonic acids under Fenton oxidative conditions
Authors: Teixeira, António P. S.; Teixeira, Fátima C.; Rangel, C. M.
Abstract: The development of new proton exchange membranes for PEM technology in fuel cells and electrolysers with increased durability is paramount to system's lifetime and scalability. In this work, new modified Nafion membranes doped with bisphosphonic acids are proposed with increased resilience to chemical degradation by H2O2/Fe2+, mimicking ex-situ radical attack to membrane structure. Relevant properties were evaluated throughout Fenton's test using fluoride ion release and gravimetry determinations, and by ATR-FTIR spectros-copy and SEM before and after the chemical degradation. The new membranes showed a very good chemical stability after oxidative degradation under Fenton's test conditions at 80 degrees C, with more durability than Nafion 115 commercial membrane. After chemical degradation, the proton conduction of the membranes was assessed through EIS which reveals a decrease in the proton conductivity of all membranes, with the new modified membranes showing a smaller decrease of their proton conduction properties than Nafion 115 membrane. Fluoride ion release, weight loss measurements and ATR-FTIR spectros-copy data analysis suggest degradation of the side chain of the ionomer.2023-07-31T23:00:00ZIssue 2 - “Update on adverse respiratory effects of indoor air pollution” Part 1): Indoor air pollution and respiratory diseases: A general update and a Portuguese perspective
http://hdl.handle.net/10174/35227
Title: Issue 2 - “Update on adverse respiratory effects of indoor air pollution” Part 1): Indoor air pollution and respiratory diseases: A general update and a Portuguese perspective
Authors: Rufo, JC; Annesi-Maesano, I; Carreiro-Martins, P; Moreira, A; Sousa, AC; Pastorinho, MR; Neuparth, N; Taborda-Barata, L
Abstract: Objective
To quantify the impact of different air pollutants on respiratory health based on robust estimates based on international data and to summarise the evidence of associations between indoor exposure to those pollutants and respiratory morbidity in the Portuguese population.
Results
Several systematic reviews and meta-analyses (MA) at the world level demonstrate the impact of indoor air quality on respiratory health, with indoor particulate matter and gasses exerting a significant effect on the airways. Volatile organic compounds (VOC) have been related to asthma and lung cancer. However, only meta-analyses on biomass use allowed documentation of long-term respiratory effects. While early publications concerning Portuguese-based populations mainly focused on indoor exposure to environmental tobacco smoke, later studies relocated the attention to relevant exposure environments, such as day care buildings, schools, residences and nursing homes. Looking at the pooled effects from the reviewed studies, high levels of carbon dioxide and particulate matter in Portuguese buildings were significantly associated with asthma and wheezing, with VOC and fungi showing a similar effect in some instances.
Conclusions
Despite the significant reduction of indoor air pollution effects after the 2008 indoor smoking prohibition in public buildings, studies show that several indoor air parameters are still significantly associated with respiratory health in Portugal. The country shares the worldwide necessity of standardisation of methods and contextual data to increase the reach of epidemiological studies on household air pollution, allowing a weighted evaluation of interventions and policies focused on reducing the associated respiratory morbidity.2023-05-23T23:00:00ZEffect of thermal and chemical treatments used for SARS-COV-2 inactivation in the measurement of saliva analytes
http://hdl.handle.net/10174/35137
Title: Effect of thermal and chemical treatments used for SARS-COV-2 inactivation in the measurement of saliva analytes
Authors: Lamy, Elsa; Rubio, Camila; Carreira, Laura; Capela e Silva, Fernando; Martinez-Subiela, Silvia; Tecles, Fernando; Lopez-Jornet, Pia; Céron, Jose; Tvarijonaviciute, Asta
Abstract: The present study aims to assess the effects of thermal and chemical inactivating procedures, that can be used for SARS-CoV-2 inactivation, on different salivary analytes. SDS-Polyacrylamide Gel Electrophoresis (SDS-PAGE) protein profile and a panel of 25 specific biomarkers of oxidative status, stress, metabolism and tissue damage were evaluated in samples subjected to different treatments: thermal (65 °C or 92 °C) and chemical with detergents [sodium dodecyl sulphate (SDS), Triton X-100 or NP-40]. Salivary SDS-PAGE profile was most affected by heating at 92 °C, with three and two protein bands decreasing and increasing their expression levels, respectively. This treatment also affected the results of several enzymes, with some of them being also affected by heating at 65 °C and incubation with SDS. The use of Triton X-100 or NP-40 resulted in increased values of cortisol, triglycerides and glucose, not affecting the other tested biomarkers. The present results will help researchers and clinicians to select the best protocols to work in safe conditions with saliva, taking into account the target analyte planned to be measured.2022-06-07T23:00:00ZPsychological adjustment, quality of life and well-being in a German and Portuguese adult population during COVID-19 pandemics crisis
http://hdl.handle.net/10174/34287
Title: Psychological adjustment, quality of life and well-being in a German and Portuguese adult population during COVID-19 pandemics crisis
Authors: Candeias, A.; Galindo, E.; Stueck, M.; Portelada, A; Knietzsch, J.
Abstract: Introduction: The pandemics crisis had consequences in psychological adjustment of persons all over the world. The current study analyzes comparatively the topics of quality of life, and well-being, considering as predictors trait anxiety, feeling of threat, difficulty to relax, empathy and pro-social attitude, health care, sleep quality and optimism, in a population of German and Portuguese adults during the pandemics, in order to obtain a deeper understanding of the psychological reactions to crisis across countries and cultures.
Methods: A sample of 470 adults divided in three age groups – —young adults (18—34 years), middle-age adults (34–54 years) and old adults (55 years and older)— completed a self-report questionnaire assessing socio-demographic data, quality of life, well-being, quality of sleep, trait anxiety, Coronavirus threat, optimism regarding the pandemics, difficulty to relax, empathy, and pro-social attitude during the pandemics period.
Results: Portuguese participants expresses higher empathy and pro-social attitude and health care but in Germany people have higher quality of sleep. Young adults (a) rated their quality of life lower than middle-age adults and old adults, (b) showed also lower optimism than middle-age and old adults, and (c) showed lower well-being than middle-age,.
Conclusions: Young adults rated their quality of life, optimism and well-being during pandemics lower than middle-age and old adults, and experienced higher levels of trait anxiety and difficulty to relax. It seems that young adults show a lower psychological adjustment than other age groups during COVID-19 crisis. It is concluded that quality of life, optimism, and well-being during the pandemics are affected differently according to country and group of age, suggesting individual differences across cultures and ages, and consequently the need of specific interventions to cope with the psychological reactions to pandemics crisis.2021-01-01T00:00:00Z