Funding for this research was provided by:
Japan Society for the Promotion of Science (17K01759)
Received: 4 September 2019
Accepted: 25 March 2020
First Online: 15 April 2020
Ethics approval and consent to participate
: This study was approved by the Human Subjects Committees of the Osaka Kyoiku University in accordance with the guidelines set forth by the Declaration of Helsinki. All subjects provided verbal and written informed consent before participating in this study.
: Not applicable.
: The authors declare that they have no competing interests.