In {HEAD ~ one embodiment} of {TAIL ~ the present invention}, this ratio is from about 1:2 to about 4:1 
In { HEAD ~ one embodiment } of { TAIL ~ the present invention } , this ratio is from about 1:2 to about 4:1
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH