1. University of Texas Health Sciences Center, Houston, TX, USA
2. University of California Los Angeles, Los Angeles, CA, USA
3. University of Colorado, Aurora, CO, USA
4. McGill University, Montreal, Canada
5. Hospital Beatriz Ângelo, Loures, Portugal
6. Johns Hopkins University, Baltimore, MD, USA
7. University of Modena and Reggio Emilia, Modena, Italy