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- Photochemical oxidation of polyethylene terephthalate microplastics adsorbed on sand and silica surfacesPublication . Q. V. da Costa, Camila; Nobahar, Amir; Egea-Corbacho, Agata; Jockusch, Steffen; Power, Deborah Mary; Ramamurthy, Vaidhyanathan; Da Silva, José PauloThe environmental contamination by plastics, microplastics, and related compounds is a major concern. While the detection and release of micro- and nanoparticles from these materials have been widely studied, the formation and release of molecules resulting from their degradation in the environment have been overlooked. This work presents a study of the products released from poly(ethylene terephthalate) (PET) irradiated as pure particles and adsorbed on silica and sand surfaces under different irradiation conditions. The role of oxygen was also evaluated. The products were identified by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-high resolution mass spectrometry (LC-HRMS). The main released molecules can be accounted for by considering the cleavage of alpha- and beta-bonds next to the ester moiety of the polymer chain. Volatile products such as benzene as well as monomer units of the polymer and related products were identified. In the presence of oxygen, acetic acid and products resulting from hydroxylation at the benzenic ring or at the ethyl moiety were detected. Adsorption on silica and sand has little effect on the photoproduct distributions. The irradiation at 360 nm leads to distributions similar to the ones observed at 257 nm, but the reaction rate is lower. The identified product ethylene terephthalate is a marker of PET plastics and particles and can therefore be used to evaluate the environmental contamination by this polymer material.
- Low handgrip strength is associated with falls after the age of 50: findings from the Brazilian longitudinal study of aging (ELSI-Brazil)Publication . Santos, André Pereira dos; Cordeiro, Jéssica Fernanda Correa; Abdalla, Pedro Pugliesi; Bohn, Lucimere; Sebastião, Emerson; Silva, Leonardo Santos Lopes da; Tasinafo-Júnior, Márcio Fernando; Venturini, Ana Cláudia Rossini; Andaki, Alynne Christian Ribeiro; Mendes, Edmar Lacerda; Marcos-Pardo, Pablo Jorge; Mota, Jorge; Dalmo Roberto Lopes Machado; Lopes Machado, Dalmo RobertoAim This study examined the association of low handgrip strength (HGS) for falls in middle-aged adults and older adults every half-decade of life. Methods This cross-sectional study was conducted using the public data from the first wave of the Brazilian Longitudinal Study of Aging (ELSI-Brazil). The participants were allocated into seven age groups 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, and ≥ 80 years. Binary logistic regression analysis was performed to identify the odds ratio (OR) of low HGS to the falls regardless of confounding variables such as sex, balance, gait speed, and total number of health conditions. Results A total of 8,112 participants aged 50–105 years (median = 62.0 years): 3,490 males (median = 60.0 years) and 4,622 females (median = 63.0 years) attended the study. Altogether, 21.5% of participants experienced at least one fall. HGS gradually decreases over each half-decade of life. In addition, low HGS presented a significative OR (p < 0.05) for falls for age groups, until 80 s, even when considering confounding variables. Conclusions Low HGS is associated with falls in middle-aged adults over their 50 s and remained a strong measure of falls across each subsequent half-decade of life, until 80 s.