Funding for this research was provided by:
Department of Education of Hebei Province (ZD2019089)
Article History
Received: 29 May 2020
Accepted: 15 November 2020
First Online: 24 November 2020
Compliance with Ethical Standards
:
: Zhihong Shi declares that she has no conflict of interest. Weiyue Pang declares that she has no conflict of interest. Man Chen declares that she has no conflict of interest. Yifan Wu declares that he has no conflict of interest. Hongyi Zhang declares that he has no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: Informed consent is not applicable for the nature of this study.