The invention provides compounds which are useful as inhibitors of metalloproteases, and which are effective in treating conditions characterized by excess activity of these enzymes. The brightness control circuit receives a luminance adjusting signal, adjusts only a part of the light volume adjusting signals, and fixes output of the rest of the light volume adjusting signals. The circuitry can additionally or alternatively be operative to determine which of the calibration steps, if any, to present as a next calibration step based on whether a given calibration step is successful. Also, the content provider can be a cable or satellite television provider, for example. The embodiment determines whether the search finds a match between data included in the search statement, and particular ontological data associated with one or more of the characteristic nodes of the data structure.