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).
Nimbostratus clouds are formed when a slowly rising warm air mass collides with stratus clouds. The nimbostratus cloud is a mid-altitude cloud, occurring higher in the atmosphere than stratus clouds do. Another type of stratus cloud is the altostratus cloud. These clouds have a blue appearance, and also occur at low altitudes. The altostratus cloud also produces light precipitation such a drizzling rain.