Funding for this research was provided by:
National Natural Science Foundation of China (81903794)
Fundo para o Desenvolvimento das Ciências e da Tecnologia (162/2017/A3)
China Postdoctoral Science Foundation (2019M653299)
Research Committee of the University of Macau (MYRG2018-00239-ICMS)
Text and Data Mining valid from 2020-03-10
Received: 24 January 2020
Accepted: 23 February 2020
First Online: 10 March 2020
Ethics approval and consent to participate
: Not applicable.
: The manuscript is approved by all authors for publication.
: The authors declare that they have no competing interests.