Funding for this research was provided by:
Humanity and Social Science Youth Foundation of Ministry of Education of China (18YJCZH164)
Article History
Received: 30 April 2019
Accepted: 10 May 2019
First Online: 24 May 2019
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.
: 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.