1. Faculdade de Ciências da Universidade de Lisboa,Instituto de Biofísica e Engenharia Biomédica,Lisboa,Portugal,1749-016
2. The University of Texas at Austin,Applied Research Laboratories,Walker Department of Mechanical Engineering,Austin,TX,USA,78713-8029
3. The University of Texas at Austin,Electrical and Computer Engineering Department,Austin,TX,USA,78712-1139