a computer programmed for analyzing said images for determining the migration of {TAIL ~ the cell} over {HEAD ~ time}; and 
a computer programmed for analyzing said images for determining the migration of { TAIL ~ the cell } over { HEAD ~ time } ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH