Funding for this research was provided by:
National Science Council (NSC101-2311-B-005-001)
Text and Data Mining valid from 2019-09-23
Received: 27 April 2019
Accepted: 8 September 2019
First Online: 23 September 2019
Ethics approval and consent to participate
: Not applicable.
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: The authors declare that they have no competing interests.