A restraining device for use in a water environment includes a plurality of tendrils that can be launched from a submerged device when an unauthorized swimmer is proximate the restraining device. Magnetotherapeutic joint wraps that are flexible and elastic incorporate superstrong magnets in an attachably detachable manner so as to provide magnetotherapy to joints and surrounding tissues. The method further includes performing a thresholding operation on the image flattened by differencing, so as to obtain a segmented image, =seg1) in which relief elements appear white on a black background. At least one heat-absorbing material is positioned within the bit body at least proximate to the at least one cutting element. This device includes as a standard a biological sample selected from a pool of blood plasmas from more than 200 healthy patients. This only requires one or two frames to synchronize the display horizontal synchronization signal to the external horizontal synchronization signal, and will not cause the user to perceive display pauses or flickers.