Improved cambered vanes are constructed for use within a vaned turbocharger and comprise an inner airfoil surface oriented adjacent a turbine wheel, and an outer airfoil surface oriented opposite the inner airfoil surface. A method according to another embodiment comprises forming an array of readers, wherein the track width of an inner reader of the array is greater than a track width of at least some outer readers positioned on two opposite sides thereof and aligned therewith. The lubricant composition for a refrigerator is used for a refrigerator which uses a refrigerant having a specific structure such as an unsaturated fluorohydrocarbon and being usable in current air-conditioning systems for cars or the like. When a request to participate in a group call is received, it is examined to see if it contains a group call ID or other group call indicator.