Methods and apparatus for dynamically compensating for the effects of interference between multiple wireless communications apparatus. A call setup request is received from a user terminal of the user at a first network element of the first packet-based communication network, the authorization request comprising a first user identity. Sequences as to whether to apply minoring and subband hopping amount are cell-specific random numbers, and are generated independently or in combination. The ball screw axis is disposed in the vicinity of the substantial center of sliding surfaces of the slider. The article has a portion which is arranged centrally between the longitudinal side edges and which is free of the adhesive fastening means. The novel salts may be used as conductive andor light emitting components in electronic devices.