1. Fellow, Department of Pharmacology, University of Texas Health Science Center at Dallas, 5323 Harry Hines Blvd. Dallas, TX 75235, US.
2. Medieolegal director and research director, respectively, Southwest Institute for Natural Substances, Dallas, TX, US.
3. Chief toxicologist, Bexar County Medical Examiner's Office, San Antonio, TX and associate professor, Department of Pathology, University of Texas Health Science Center at San Antonio, US.