Transcranial Doppler Assessment of Cerebral Flow Velocity During Cognitive Tasks Roger E. Kelley, MD; Jen Y. Chang, MS; Nancy J. Scheinman, PhD; Bonnie E. Levin, PhD; Robert C. Duncan, PhD; and Shih-Chang Lee, PhD Background and Purpose: The purpose of this study was to assess the ability of transcranial Doppler ultrasonography to detect selective circulatory changes during cognitive activity. Methods: We measured cerebral artery flow velocity in 21 normal volunteers by transcranial Doppler ultrasonography during rest followed by cerebral activation. Mean and peak systolic
Neptune has dark storms and eight named moons, although there are more than 8 moons. Source(s): My memory http://burro.astr.cwru.edu/stu/neptune_m...
correction, The moon has 4 main phases, new, quarter, full, and third quarter moon's. You may think using common sense that what the other answer was correct, but it was not â¦ . Since the sun only faces one side of the moon, only one side of the moon is lit up. That side faces the sun. On earth people see a new moon as a dark moon because the half that is lit faces the sun and away from the earth making a moonless sky. The Quarter moon is when the moon is at a 90 degree angle from the sun.