EXPRESSION VECTORS FOR EXPRESSION OF A PROTEIN IN HIGHER EUKARYOTIC HOST CELLS COMPRISING AN ENHANCER/PROMOTER UNIT, A PROTEIN ENCODING SEQUENCE, SIGNAL SEQUENCES, AND SELECTION MARKER GENE, HOST CELLS TRANSFORMED THEREBY, A METHOD FOR PRODUCING THE PROTEIN USING THE TRANSFORMED HOST CELLS AND HOST CELLS TRANSFORMED BY THE VECTORS FOR CLONING AND MULTIPLICATION OF THE VECTORS

摘要

PCT No. PCT/GB85/00267 Sec. 371 Date Feb. 4, 1986 Sec. 102(e) Date Feb. 4, 1986 PCT Filed Jun. 14, 1985 PCT Pub. No. WO86/00124 PCT Pub. Date Jan. 3, 1986.Geothermal energy is recovered from an underground zone of relatively hot strata via a borehole into which is inserted a heat pipe system containing a working fluid, the heat pipe system comprising an assembly of two tubes in concentric relation, the inner tube being constituted by a relatively small diameter capillary for the return of working fluid to the vicinity of the zone of the relatively hot strata. The working fluid is preferably assisted in its return under gravity by means of a pump. The system includes heat exchange means operable to recover thermal energy from the working fluid. A third and outermost tube may be used to reduce heat losses, this third tube enclosing the two tubes over all but that part of their length which is in the zone of relatively hot strata.