{TAIL ~ The centrifuge} includes {HEAD ~ a receiving chamber} with a selectively formed annular slot therein 
{ TAIL ~ The centrifuge } includes { HEAD ~ a receiving chamber } with a selectively formed annular slot therein
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH