Funding for this research was provided by:
Research Institute in Humanities and Social Sciences of the Ministry of Education (19YJC190031)
National Natural Science Foundation of China (81571337)
Youth Teacher Initial Funding in Zhengzhou University (32220389)
Article History
First Online: 13 July 2019
Compliance with Ethical Standards
:
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.
: The authors declare that they have no conflict of interest.