Funding for this research was provided by:
Institute scientific Research Fund "Sailing Project" (DTQH201608)
Received: 8 January 2021
Accepted: 6 October 2021
First Online: 9 November 2021
: This study was conducted in accordance with the Declaration of Helsinki and approved by the ethics committee of Jingdi Lunke Zi (2017) No. (046)-01.Written informed consent was obtained from all parents/local guardians.
: The manuscript is not submitted for publication or consideration elsewhere.
: The authors declare that they have no competing interests.