Adv Mater 2014 Sep 19;26(34):5976-85. Epub 2014 Aug 19.
University of L'Aquila, International Research Center for Mathematics & Mechanics of Complex System (MEMOCS), Via S. Pasquale, 04012, Cisterna di Latina, (LT), Italy; ENEA, C.R. Casaccia, Via Anguillarese 301, Santa Maria di Galeria, 00123, Rome, Italy.