This study was partially supported by grants from Shaanxi Province (grant no. SGH140537, to Yin-Ping Zhang), the Xi’an Jiaotong University Fund (grant no. 202107164, to Yin-Ping Zhang), the Fund of Hunan Social Science Achievement Appraisal Committee (grant no. XSP21YBC228, to Dandan Zhang), the Anti-COVID-19 Special Project from Hunan Provincial Science & Technology Department (grant no. 2020SK3040, to Yongjun Chen), and the fund of innovative program on the COVID-19 prevention and treatment from Hengyang Science and Technology Bureau (grant no. 202010031581, to Dandan Zhang).