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Abstract The global concern over water pollution caused by contaminants of emerging concern has been the subject of several studies due to the complexity of treatment. Here, the synthesis of a graphene oxide-based magnetic material (GO@Fe3O4) produced according to a modified Hummers’ method followed by a hydrothermal reaction was proposed; then, its application as a photocatalyst in clonazepam photo-Fenton degradation was investigated. Several characterization analyses were performed to analyze the structure, functionalization and magnetic properties of the composite. A 23 factorial design was used for the optimization procedure to investigate the effect of [H2O2], GO@Fe3O4 dose and pH on clonazepam degradation. Adsorption experiments demonstrated that GO@Fe3O4 could not adsorb clonazepam. Photo-Fenton kinetics showed that total degradation of clonazepam was achieved within 5 min, and the experimental data were better fitted to the PFO model. A comparative study of clonazepam degradation by different processes highlighted that the heterogeneous photo-Fenton process was more efficient than homogeneous processes. The radical scavenging test showed that $${O}_{2}^{\cdot -}$$ O 2 · - was the main active free radical in the degradation reaction, followed by hydroxyl radicals (•OH) and holes (h+) in the valence layer; accordingly, a mechanism of degradation was proposed to describe the process.

The global concern over water pollution caused by contaminants of emerging concern has been the subject of several studies due to the complexity of treatment. Here, the synthesis of a graphene oxide-based magnetic material (GO@Fe3O4) produced according to a modified Hummers' method followed by a hydrothermal reaction was proposed; then, its application as a photocatalyst in clonazepam photo-Fenton degradation was investigated. Several characterization analyses were performed to analyze the structure, functionalization and magnetic properties of the composite. A 23 factorial design was used for the optimization procedure to investigate the effect of [H2O2], GO@Fe3O4 dose and pH on clonazepam degradation. Adsorption experiments demonstrated that GO@Fe3O4 could not adsorb clonazepam. Photo-Fenton kinetics showed that total degradation of clonazepam was achieved within 5 min, and the experimental data were better fitted to the PFO model. A comparative study of clonazepam degradation by different processes highlighted that the heterogeneous photo-Fenton process was more efficient than homogeneous processes. The radical scavenging test showed that O 2 · - was the main active free radical in the degradation reaction, followed by hydroxyl radicals (•OH) and holes (h+) in the valence layer; accordingly, a mechanism of degradation was proposed to describe the process. [ABSTRACT FROM AUTHOR]

Abstract Sedentary behavior (SB) is associated with health impairments, while physical activity (PA) has been a protective factor. It is unclear whether SB and PA are associated with occurrence of signs and/or symptoms (SS) during cardiac rehabilitation program (CRP) exercise sessions. The objective was to evaluate the association between SB and PA with occurrence of SS. Was included 48 patients from a CRP program (64.7 ± 10.4 years-old). Daily time and % of time of SB and weekly time in moderate-to-vigorous-intensity [MVPA], % of MVPA time, steps/day, and steps/minute were accelerometer-measured. Patients were followed-up during 24 CRP sessions, for accompaniment of SS. Age, sex, and comorbidities (hypertension, diabetes, dyslipidemia, obesity) were covariates. Log-transformed values of SB, MVPA and steps/day were also analyzed. As results, 43.7% (n = 21) of participants presented occurrence of signs, 62.5% (n = 30) presented occurrence of symptoms, and 81.2% (n = 39) present occurrence of SS. In fully adjusted model, % of time in MVPA (β: −0.449,p = 0.045) and steps/minute (β: −0.244,p = 0.026) were inversely associated with occurrence of symptoms. No association was observed between SB and PA and occurrence of signs. The occurrence of symptoms and SS among CRP participants was directly associated with SB and inversely associated with variables of PA.