The present invention relates to the use of isotopically labeled derivatives of isoniazid, ethionamide and related compounds as effective therapy for the treatment of mycobacterial diseases, including Mycobacterium tuberculosis. In general, in one implementation, the technique includes: flagging nodes in one or more object hierarchies as entry points and generating a virtual hierarchy including a virtual root and the nodes flagged as entry points depend directly from the virtual root. The software and receivers are generally configured to implement one or more aspects of the methods disclosed herein, and the systems generally include those that embody the inventive receivers disclosed herein. The image files are iteratively ascertained to have smaller than a pre-specified file size.