Disclosed herein is an acrylic resin film having excellent heat resistance and mechanical strength, less fish-eyes, and high transparency. A cardiac stimulator receives heart beat signals from the heart and determines a measurement of heart rate variability based on statistical data derived from the heart beat signals and sensing data derived from a sensor. The encapsulated Ethernet frames may be input to a conventional network interface card of a personal computer or laptop. An electrical contact base is connected to the bottom wall of the adaptor casing and it has a conventional externally threaded outer electrical contact surface that would be received into a conventional incandescent lamp socket. , of 300 to 900 and a viscosity at 60\xb0 C.