1. Medical examiner, Dallas County, Southwestern Institute of Forensic Sciences, Dallas; and associate professor, Department of Pathology, University of Texas, Southwestern Medical School at Dallas, Texas 75235, US.
2. Chief toxicologist, Southwestern Institute of Forensic Sciences, Dallas; and assistant professor in forensic sciences, Departments of Pathology and Pharmacology, University of Texas, Southwestern Medical School at Dallas, Texas 75235, US.