Funding for this research was provided by:
Japan Society for the Promotion of Science (JP15H05939)
JAXA (Institutional funding)
Received: 12 September 2018
Accepted: 19 November 2018
First Online: 6 December 2018
Ethics approval and consent to participate
: The study protocol was approved by the Institutional Ethical Committee of Nihon University School of Medicine (27-7-0-1) and JAXA (79–-4-1). Written informed consent and medical histories were obtained from all participants before the study began.
: Not applicable.
: The authors declare that they have no competing interests.
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