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Fast increased amount of excess activated sludge (EAS) from wastewater treatment plants has aroused universal concerns on its environmental risks and demands for appropriate treatments, while effective treatment is dependent upon proper pretreatment. In this study, air-supplied microbubbles (air-MBs) with generated size of 25.18 to 28.25 μm were used for EAS pretreatment. Different durations (30, 60, 90, and 120 s) yielded sludge with varied physiochemical conditions, and 60 s decreased sludge oxidation status and significantly increased adenosine triphosphate (ATP) content. Soluble, loosely-bound, and tightly-bound extracellular polymeric substances (SEPS, LB-EPS, and TB-EPS) were extracted from the sludge through a stepwise approach and examined through three-dimensional excitation-emission matrix (3D-EEM) and quantitative analysis. The results showed that 60- and 120-s treatments generated stronger fluorescence intensities on dissolved organic matters (DOMs) of protein-like and fulvic acid in LB-EPS and TB-EPS, which indicated the decrease of counterparts in EAS, and therefore facilitated sludge dewaterability and reduction. The dominant microbial communities in EAS, including Proteobacteria, Bacteroidota, Chloroflexi, and Actinobacteriota, were not significantly affected by MB pretreatment. The results collectively revealed the effects of MB pretreatment on EAS and indicated that MBs could be an effective pretreatment technique for EAS treatment process. [ABSTRACT FROM AUTHOR]

Backgrounds: Freezing of gait (FOG) and cognitive impairment are serious symptoms of Parkinson's disease (PD). Understanding the association between FOG and cognition may help formulate specific interventions for PD individuals. Objectives: We aimed to investigate the associations of cognitive impairment in different domains with FOG status using multiple neuropsychological tests. Methods: Two cohorts including 691 and 104 participants were recruited from Parkinson's progression markers initiative (PPMI) and central China, respectively. All participants underwent FOG assessment and neuropsychological tests, and 595 individuals from PPMI and 51 from central China were enrolled for longitudinal observation. Cross-sectional and longitudinal associations between cognition and FOG status were evaluated using multivariable-adjusted models. Results: Worse cognitive performances were observed in patients with FOG compared to those without FOG in both cohorts (β = − 0.020, p < 0.001) using multivariate-adjusted models. Moreover, patients with progressive FOG during follow-up manifested more serious cognitive declines (HR = 1.40, 95% CI = 1.07–1.80). The FOG was mainly associated with the decline of executive, attention, and orientation. Furthermore, FOG was associated with higher levels of cognition-related biomarkers including T-tau, P-tau, and NfL in cerebrospinal fluid (p < 0.050). Conclusions: FOG is a risk factor for cognitive decline in PD, which emphasizes the need for early detection and monitoring of cognitive changes and interventions on cognitive impairments in PD patients with FOG. [ABSTRACT FROM AUTHOR]