Abstract: A heat pump system (100) comprising a first hydraulic circuit (1) suitable to carry out a heat pump cycle in solution with a first operating fluid which, during part of said cycle, is combined with at least one auxiliary substance so as to form a material system therewith, and a second hydraulic circuit (2) adapted to carry out a compression heat pump cycle with a second operating fluid. The first hydraulic circuit (1) comprises a first treatment device (10) for the material system for separating from the material system at least a fraction of the first operating fluid; a first condenser (11) for at least partially condensing the first operating fluid which has been separated; a first evaporator (13) for at least partially evaporating the first operating fluid which has been condensed, and a second treatment device (14) for the material system for again incorporating in the material system the first operating fluid which has been evaporated.

Abstract: A stent and method of forming a stent include a wire bent into a waveform spirally wrapped into a hollow cylindrical shape. The waveform includes a first end portion, a middle portion, and a second end portion. The middle portion of the waveform includes a first amplitude and a first period. The first end portion of the waveform includes a first plurality of amplitudes and a first plurality of periods, wherein the first plurality of amplitudes decrease from adjacent the middle portion to a first end of the wire and first plurality of frequencies increase from adjacent the middle portion to the first end of the wire. The waveform may also include a second end portion with a second plurality of amplitudes and a second plurality of periods, wherein the second plurality of amplitudes decrease from adjacent the middle portion to a second end of the wire and the second plurality of frequencies increase from adjacent the middle portion to the second end of the wire.