Authors' contributions
Hua Gao, Baojun Wang contributed to the conception and design of the study. Zhenyu Liu, Hua Gao, and Xiaodong Bai analyzed the data, wrote the manuscript, and drew the figures. Gang Wang, Guoqiang Xu, Ji Ma, Jiatian Wang, Wentao Chen, and Yijun Wang collected and assembled the data. Hua Gao, Zhenyu Liu, and Baojun Wang contributed to the critical revision of the manuscript. All authors contributed to the article and approved the submitted version.