1. Division of Comparative Pathology, Department of Pathology, Carver College of Medicine, University of Iowa, 500 Newton Road, 1167 ML, Iowa City, IA 52242, USA
2. Department of Neurosurgery, Carver College of Medicine, University of Iowa, 500 Newton Road, 1167 ML, Iowa City, IA 52242, USA
3. Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA