Effects of indoor air purification intervention on blood pressure, blood‑oxygen saturation, and heart rate variability: A double-blinded cross-over randomized controlled trial of healthy young adults - Xi Xia; Xinyi Niu; Kahung Chan; Hongmei Xu; ZhenXing Shen; Jun-ji Cao; ShaoWei Wu; Hong Qiu; Kin-Fai Ho (Science of The Total Environment, 2023)