Among the eight regions, four regions are provided in {TAIL ~ the outer peripheral portion} and {HEAD ~ four regions} are provided in the inner peripheral portion 
Among the eight regions , four regions are provided in { TAIL ~ the outer peripheral portion } and { HEAD ~ four regions } are provided in the inner peripheral portion
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH