Funding for this research was provided by:
National Natural Science Foundation of China (32071091)
Accepted: 5 March 2021
First Online: 2 April 2021
: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
: The study was reviewed and approved by the research committee in Beijing Normal University, as well as by the committee in local government. All subjects and their parents were provided with written informed consent.