This invention pertains to a composition that can be used to heal cracks in plastics and other substrates. A liquid supply provides a flow of a pressurized liquid through the liquid ejector channel from the liquid supply channel. The user may add modules from the library to a webpage layout design area. A naming layer may employ circuits to establish a distributed database of associations between network node addresses and their network locations. The actuator arrangement is provided within and rotates with the outer shaft. The photocathode also includes integral spacer structure which extends toward and physically touches a microchannel plate of the image intensifier tube in order to establish and maintain a desirably precise and fine-dimension spacing distance G between the photocathode and the microchannel plate.