Atherosclerosis in the carotid arteries, two large arteries in the neck that carry blood to the brain, is a major risk factor for ischemic stroke. Symptoms of stroke include: 1  Sudden numbness, weakness, or paralysis of face, arm or leg, especially on one side of the body. carotid endarterectomy is a surgical procedure in which a doctor removes fatty deposits blocking one of the two carotid arteries, the main supply of blood for the brain.
Polar stratospheric cloud. Polar stratospheric clouds or PSCs, also known as nacreous clouds (/ËneÉªkriË.És/, from nacre, or mother of pearl, due to its iridescence), are clouds in the winter polar stratosphere at altitudes of 15,000â25,000 meters (49,000â82,000 ft).
Stratus clouds bring gentle rain and snow and may hide the sun from view. They occur below 2,000 meters. Nimbostratus Clouds. These are dark clouds occurring under 2,400 meters or 8,000 feet. Nimbostratus clouds bring down rain and are seen mostly in the middle latitudes of the earth. Cumulus Clouds. These are those big, puffy clouds that look like cotton. Cumulus clouds are measured at below 2,000 meters or 6,500 feet.