Air pollution may accelerate cognitive aging, it is unclear whether large-scale interventions by Clean Air Act can mitigate the cognitive deterioration. Here, we conducted a difference-in-differences analysis based on Chinese Longitudinal Healthy Longevity Survey during 2014 and 2018. Intervention group came from where the government set a strict target of reducing air pollution, whereas control group lived in areas without reduction target. Global cognitive functions were measured using the Mini-Mental State Examination (MMSE). We found the intervention group with implementing Clean Air Act had a significantly smaller decline in MMSE score compared to the control group. Interquartile increases in PM2.5 and SO2 concentrations were significantly associated with a faster decline of MMSE score by 1.78 and 0.92 points, respectively. Implementing stringent clean air policies, especially in low- and middle-income countries may mitigate the risk of cognitive aging in older people.

Studies show that in the cutting process, different parameters have different importance to performance indicators. Accordingly, it is necessary to define the importance of different parameters to performance indicators to study the correlation between parameters and performance indicators accurately. In the present study, the side milling process of titanium alloy by the end milling cutter is considered as the research object, analytic hierarchy process and grey-fuzzy evaluation method are used to evaluate the importance of tool geometric parameters and operating parameters on tool wear rate and material removal. It is found that applying the average method to remove the parameter level, makes each parameter calculate the same result. Therefore, it should be combined with other data processing methods to resolve the above problem. Finally, the range analysis method is applied to obtain the optimal parameter level of different parameters for each performance indicator in the orthogonal table. The obtained results show that helix angle has the highest importance comprehensive evaluation value, followed by feed per tooth. For the tool wear rate and material removal amount, the optimal horizontal combination of parameters was obtained successively.