Abstract: An ultrasonic surgical device is disclosed including a surgical tool including a proximal transducer mounting portion defining a surface, a distal end effector end, and a waveguide disposed therebetween, the waveguide extending along a longitudinal axis. The ultrasonic surgical device further includes a transducer is in mechanical communication with the surface of the transducer mounting portion. The transducer is configured to operate in a D31 mode with respect to the longitudinal axis of the waveguide. Upon activation by an electrical signal having a predetermined frequency component, the transducer is configured to induce a standing wave in the surgical tool to cause the end effector to vibrate, the standing wave having a wavelength proportional to the predetermined frequency component of the electrical signal.

Abstract: In accordance with the invention there is provided an extracorporeal blood circulation system including a drip chamber having a blood inlet in its top and a blood outlet in its bottom, such chamber during operation containing blood in its bottom portion and air in its top portion, an air passage communicating with the top of the chamber, an air pump communicating with the atmosphere and with the passage for pumping air through the passage from the chamber into the atmosphere and from the atmosphere into the chamber, and means for selectively actuating the pump to either pump air into or out of the chamber.