A programmable channel-swap crossbar switch for swapping signal flow from one channel to another within an Ethernet physical layer device is presented. The applicator comprises an elongate tube body having a proximal and a distal end and defining an open internal area. The assembly further includes a dielectric mirror layer disposed on a location of the rear surface of the window cover corresponding to the non-display area which selectively reflects light incident through the window cover to provide a metallic color sense to a user and a light absorbing layer absorbing light transmitted through the dielectric mirror layer. An inspection apparatus for inspecting a surface of a substrate produces a crossover from electrons emitted from an electron beam source 25\u20221, then forms an image under a desired magnification in the direction of a sample W to produce a crossover. Aspects of the disclosure include a peptidyl propenoyl hydrazide compositions that inhibit proteases, for example cysteine proteases, either in vivo or in vitro. The method further includes suppressing the supply of samples of the signal at a middle portion of the symbol period.