1. Department of Mechanical Engineering, Mechanics of Composites Laboratory, Universidade Federal de Minas Gerais, 6627 Antonio Carlos Avenue, Belo Horizonte, MG 31270-901, Brazil; On sabbatical at Aerospace and Mechanical Engineering Department, University of Arizona, 1130 N Mountain Avenue, Tucson, AZ 85721, USA
2. On sabbatical at Aerospace and Mechanical Engineering Department, University of Arizona, 1130 N Mountain Avenue, Tucson, AZ 85721, USA