Sun, Peijie
Wei, Beipei
Zhang, Jiahao
Tomczak, Jan M.
Strydom, A.M.
Søndergaard, M.
Iversen, Bo B.
Steglich, Frank
Article History
Received: 18 March 2015
Accepted: 12 May 2015
First Online: 25 June 2015
Competing interests
: The authors declare no competing financial interests.