Text and Data Mining valid from 2018-08-20
Received: 17 January 2018
Accepted: 8 August 2018
First Online: 20 August 2018
Ethics approval and consent to participate
: The study obtained the approval (E2536) of the Ethics Committee of Kyoto University. Written informed consent was obtained from the participants that were included in this study.
: Not application.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.