A locking device for use with an electrical plug having a pair of spaced prongs, each prong having an aperture spaced from its free end portion, the locking device including a body member, a pair of spaced apart arm members, and an elongated member extending between the pair of arm members. Another embodiment includes a computer-implemented system helping a user learn using a detached imaging sensor. The immediate responses are scheduled, the information indicating the scheduled offset time and granted transmission duration for response of each receiver being included in the physical sublayer data unit headers within the aggregate. coli K1 disease in a mammalian subject. A method to fabricate and assemble the device is provided. Upon fabricating at least one layer of the IC on the wafer, a process monitoring tool is applied to perform a measurement at the site in at least one layer responsively to the PDP.