Affiliation: | 1. National Research Institute of Astronomy and Geophysics, Solar and Space Department, Marsed Street, Helwan, 11421 Cairo, Egypt;2. Al-Azhar University, Faculty of Science, Nasr City, 11884 Cairo, Egypt;1. Received from the University of Texas, Houston, TX, USA;2. Department of Otolaryngology, Head and Neck Surgery, USA |