1. College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai P.O. Box 505055, United Arab Emirates
2. Division of Medical Physiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, Cape Town 7602, South Africa
3. Department of Physiology, Faculty of Medicine, Misurata University, Misratah P.O. Box 2478, Libya