Silvestri, I
Testa, F
Zappasodi, R
Cairo, C W
Zhang, Y
Lupo, B
Galli, R
Di Nicola, M
Venerando, B
Tringali, C
Article History
Received: 15 April 2014
Revised: 8 July 2014
Accepted: 9 July 2014
First Online: 21 August 2014
Competing interests
: The authors declare no conflict of interest.