Compounds related to lactacystin and lactacystin Beta-lactone, pharmaceutical compositions containing the compounds, and methods of use. A number of responses to signals transmitted in a portion of the wiring system are measured to form a measured signature. The shaving aid body can be erodible and the handle is provided with a self-leveling mechanism to relatively maintain a generally coplanar relation between the top surface of the shaving aid body and the shave plane of the razor cartridge during a normal shaving operation as the shaving aid body erodes during use. In order to avoid this disadvantage, it is suggested that at least two of the users of the data network be implemented to be pilot-master-capable and one of them assume the pilot mastership according to a described method. With this construction, the precision in conversion by the analog-to-digital converter is maintained at a proper level when an environment for signal reception varies.