Share: Cervical dystonia (say: serv-ical dis-tone-ee-a) is a condition in which the muscles in the neck contract, twisting the head to one side and pulling the chin to the shoulder.Sometimes the shoulder on the affected side will also be pulled up toward the head.hare: Cervical dystonia (say: serv-ical dis-tone-ee-a) is a condition in which the muscles in the neck contract, twisting the head to one side and pulling the chin to the shoulder.
How do scientist classify air masses? Scientists classify air masses according to their general characteristics and latitude. Artic air masses form at around 60 degrees latitude, Polar masses are at around 40 â¦ degrees latitude, warm tropical air masses are at 15 degrees latitude and very hot air masses form near the equator.
1 Continental air masses are characterized by dry air near the surface while maritime air masses are moist. 2  Polar air masses are characterized by cold air near the surface while tropical air masses are warm or hot.