1. Weapons and Protection Division, Defense Research Establishment, SE-172 90 Stockholm, Sweden
2. Human Sciences Division, Defense Research Establishment, SE-172 90 Stockholm, Sweden
3. Department of Anesthesia and Intensive Care, Huddinge University Hospital, Karolinska Institutet, SE-141 86 Huddinge, Sweden
4. Department of Medical Laboratory Sciences and Technology, Division of Clinical Neurophysiology, Huddinge University Hospital, Karolinska Institutet, SE-141 86 Huddinge, Sweden