1. Laboratory of Bio-Inspired Nanomechanics, Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, 10129 Turin, Italy
2. Laboratory for Bioinspired, Bionic, Nano, Meta, Materials & Mechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy
3. School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK