The present invention relates to certain resorcinol derivatives and their use as skin lightening agents. A gel layer from the gel batch is treated with a protein sample, \u2018n\u2019 membranes are placed onto the gel layer to yield a gel pack, and the gel pack is placed between an electrode plate maintained at a fixed first voltage and an array of \u2018n\u2019 spaced generally parallel electrodes. The PHY layer is configured to construct a physical-layer service data unit based on a concatenate block, an insert shortened bits block, a Bose, Ray-Chaudhuri, Hocquenghem encoder, a remove shortened bits block, an add pad bits block, a spreader, a bit interleaver, a scrambler, and a symbol mapper. The attitude determination unit determines whether the cover member is in an open attitude or is in a closed attitude based on a closed signal and a state signal input after the open signal. The assembly is adapted to disable the counterbalancing force responsive to pivoting of the sash window.