Because the beads have {TAIL ~ a generally spherical surface}, {HEAD ~ the radius} of curvature provides an additional distinguishing characteristic by which a particular sample may be identified 
Because the beads have { TAIL ~ a generally spherical surface } , { HEAD ~ the radius } of curvature provides an additional distinguishing characteristic by which a particular sample may be identified
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 OTH OTH OTH OTH OTH OTH OTH OTH