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