Funding for this research was provided by:
Grant-in-Aid for JSPS Research Fellow (18J30015)
Text and Data Mining valid from 2020-02-13
Received: 14 February 2019
Accepted: 7 February 2020
First Online: 13 February 2020
Ethics approval and consent to participate
: Collections of samples were approved by the Governor of Okinawa Prefecture (permit numbers 28–31 and 27–1).
: Not applicable.
: The authors declare that they have no competing interests.