Received: 10 July 2018
Accepted: 5 December 2018
First Online: 21 December 2018
Ethics approval and consent to participate
: This study was conducted with the approval of the Ethical Review Board of the Graduate School of Health Sciences, Hiroshima University. The intervention was only performed on subjects who provided written informed consent.
: Not applicable
: The authors declare that they have no competing interests.
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