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...
The portion of the moon that is seen from earth is the part that is illuminated by the sun. The lunar cycle runs from new moon, or a totally dark moon, to the next new moon. When it is full moon, the moon is positioned behind the earth with regard to the sun. As the moon rises it is fully illuminated by the sun. During the new moon phase, the moon is located between the earth and the sun, so none of the side of the moon that is facing the earth is illuminated. Learn more about Our Moon