The slider includes: a first cylindrical portion having an upstream through hole penetrating therethrough; a second cylindrical portion having a downstream through hole penetrating therethrough and communicating with the upstream through hole; and a semipermeable membrane closing {HEAD ~ the upstream} through {TAIL ~ hole} 
through
The slider includes : a first cylindrical portion having an upstream through hole penetrating therethrough ; a second cylindrical portion having a downstream through hole penetrating therethrough and communicating with the upstream through hole ; and a semipermeable membrane closing { HEAD ~ the upstream } through { TAIL ~ hole }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL