Percorrer por data de Publicação, começado por "2018-11-01"
A mostrar 1 - 3 de 3
Resultados por página
Opções de ordenação
- Active polylactic acid film incorporated with green tea extract: Development, characterization and effectivenessPublication . Martins, Carla; Vilarinho, Fernanda; Sanches-Silva, A.; Andrade, Mariana; Machado, A.; Vaz, M.F.; Ramos, F.A new antioxidant active packaging film has been developed based on polylactic acid (PLA) in which green tea extract (GTE) has been immobilized by extrusion. Two GTE concentrations were tested, 1% (w/w) and 2% (w/ w). Four GT samples were compared regarding their antioxidant capacity (by DPPH radical scavenging method and β-carotene bleaching method), total phenolics content (TPC) and total flavonoids content (TFC). The commercial GTE presented with highest antioxidant capacity by the DPPH radical assay (EC50=0.12 ± 0.00 mg/mL) and the highest TPC (416 ± 9.95 mg gallic acid equivalents (GAE)/g extract) and it was selected to be incorporated in the active film. Films were evaluated regarding their mechanical properties (e.g. tensile strength decreased 12% with the incorporation of GTE in the PLA matrix and strain at break increased 9.6 and 36% with the addition of 1 and 2% of GTE) and water vapour transmission rates (watervapour barrier properties improved with the addition of higher amounts of GTE). The study of the effectiveness of PLA/GTE films against lipid oxidation was performed by the following methods: peroxide value, p-anisidine value, thiobarbituric acid reactive substances (TBARS) assay and hexanal monitoring, after packaging smoked salmon slices during different storage times (0, 7, 15, 30, 45 and 60 days). The results showed that the incorporation of GTE in the PLA films protects the smoked salmon from lipid oxidation in the different storage times tested. However, additional studies should be performed to better understand the GTE mechanism of action as the results suggest a pro-oxidant effect of PLA/GTE 2% after 60 days of storage and to evaluate the potential antimicrobial activity of active films.
- RSV attributable mortality in Portugal between 2014 and 2018Publication . Rodrigues, Ana Paula; Silva, Susana Pereira; Guiomar, Raquel; Pechirra, Pedro; Cristóvão, Paula; Nunes, BaltazarBackground: Respiratory Syncytial Virus (RSV) has been recognized as a serious pathogen in at-risk adult populations (long-term care facilities, immunocompromised). In adults, RSV infection is usually mild, but its effect on morbidity and mortality in adults can be substantial as has been previously reported (1). Given RSV has a similar seasonality pattern as influenza virus it is plausible that RSV circulation had contributed to excess all-cause mortality observed during previous winters in Portugal. This study aimed to estimate RSV attributable all-cause mortality between 2014/15 and 2017/18 autumn-winter seasons in Portugal.
- It’s not just the water: beach sand as a potentially overlooked source of human, environmental, and animal diseasePublication . Chelsea, Weiskerger; Brandão, JoãoThe connections between water, food, energy, and climate are becoming clearer as we increase our understanding of the world around us. Recreational health policy, however, is lagging behind the research. In certain situations, the impacts of this lag could substantially affect the health of beach users. In recent years, research has indicated that beach sand can be a substantial source of fecal indicator bacteria and may provide more of a risk for beachgoers than recreational water itself. Further, the prevalence of contaminants in beach sand can provide a “One Health” issue: in addition to people contacting contaminants in beach sand, wildlife and pets are also exposed to sand, potentially leading to animal diseases. Additionally, contaminants in sand may degrade the environmental health of beaches through the development of biofilms and complex microbial communities that include may pathogens and opportunists. All of these issues may be affected by climate, food, and energy development, and subsequently may cause economic problems associated with healthcare costs, enhanced beach management/cleanup, and tourism losses due to beach closures. Despite this knowledge of beach sand as a source of human, animal, economic, and environmental health concerns, only three nations have recognized sand as a potential source of beach contamination, and only one has taken steps to effectively manage sand contamination for beach health. As we move forward with research, directed by both the water, food, energy, and climate nexus and One Health frameworks, the health and safety of beachgoers will depend upon development of policies to address beach sand and water contamination.