Catheters adapted to exchange heat with a body fluid flowing through a body conduit employ helical elongate lumens for heat transfer with the body fluid. The testing scheduling system further calculates a first weighted value of each available work station by summing the failure rate value, the backlog quantities value, the test-awaited quantities value, and the distances value of each available work station, and analyzes the first weighted values to determine a preferred work station. 0, to a process for its preparation and to the use of such mixtures. The first magnetic layer has a spinel crystal structure, and the multilayer film further includes a titanium nitride layer interposed between the substrate and the first magnetic layer. The method is characterized by the metal cyanate being placed at an elevated temperature in an organic solvent and the other reactants being continuously charged into the mixture over a defined time period. The alignment mark is formed by part of the uppermost interconnection layer in a multilevel interconnection which is formed on the semiconductor chip and obtained by stacking low-permittivity insulating layers and interconnection layers.