Funding for this research was provided by:
Japan Society for the Promotion of Science (Houga (25810025), Kiban A (23244015), Kiban S (26220702))
Deutsche Forschungsgemeinschaft (IRTG 1529)
Seventh Framework Programme (PIRSES-GA-2012-319012)
Received: 5 December 2016
Accepted: 16 January 2019
First Online: 7 February 2019
Free to read: This content has been made available to all.