An optical component including at least one optical supergrating is provided. The device includes a base and a hub fixed to a position with respect to the base and removable from the base. , apoptosis promoters for cancer cells, and the like. Other embodiments reduce the thermal conduction between the two electrodes when compared to the prior art. Following detection of the cut-off state and even after turning off the light source, the control unit is operable to carry out a data storage operation in which at least part of the data is stored in the nonvolatile memory, wherein power to carry out the data storage operation is obtained from the charges previously accumulated by the capacitor. Provided is a retrofit hinge kit adapted for use with square tube frames and methods for its use.