The adjustment may be performed by adjusting the force exerted on {TAIL ~ a membrane}, which has been inserted in a wall of {HEAD ~ the reference cell} 
The adjustment may be performed by adjusting the force exerted on { TAIL ~ a membrane } , which has been inserted in a wall of { HEAD ~ the reference cell }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD