A perforating charge for use in a wellbore includes an explosive and a liner to be collapsed by detonation of the explosive. For example, the invention provides methods and compositions for the delivery of one ore more oxalate-reducing enzymes to the intestinal tracts of persons and animals. The attribute object type is defined to indicate one of a plurality of different data structure formats that are searchable through separate application programs, wherein the attribute object types in one asset class are implemented in different data structure formats. The mask covers a first portion of the magnetoresistive element layers in at least one device area.