Funding for this research was provided by:
Japan Society for the Promotion of Science (JP17K173510A, JP17H06897, JP18H02977)
Nakatomi Foundation (Research Grant)
Mitsui Sumitomo Insurance Welfare Foundation (Research Grant)
Received: 25 September 2018
Revised: 10 November 2018
Accepted: 20 November 2018
First Online: 7 December 2018
Ethics approval and consent to participate
: Ethical approval for human subjects was obtained from the Independent Ethics Committee of Hiroshima University (reference number 422-2).
: Not applicable. This manuscript does not contain any individual person’s data.
: The authors declare that they have no competing interests.
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