The invention relates to a composition containing at least one hydrophilic active principle and at least one amphiphilic polyisobutylene polymer. The compensation circuit comprises a writing driver, a distance detection circuit, an operating element and an auxiliary writing driver. The railway system also includes safety systems associated with the railway signaling systems for exchanging data between the safety systems for safely controlling the railway signaling systems. The base portion of each contact further defines a rib protruding towards the receiving room. A revamping of urea plants is also disclosed, including the revamping of ammonia stripping plants, self-stripping plants and conventional total recycle plants, wherein said duplex stainless steel is used for the tubes of the stripper.