Physical activity attenuates the association of long-term exposure to nitrogen dioxide with sleep quality and its dimensions in Chinese rural older adults

Hongli Wang, Junzhe Li, Qiang Liu, Yan Zhang, Yuan Wang, Huaibiao Li, Liang Sun, Bing Hu, Dongmei Zhang, Chunmei Liang, Jingyuan Lei, Panpan Wang, Jie Sheng, Fangbiao Tao, Guimei Chen, Linsheng Yang