Abstract: A lithotripsy assembly includes a target positioned inside a body that has an external surface. A lithotripsy dry head shock wave transducer is aimed at the target. A gel enclosure is defined at least partially by the body and the lithotripsy transducer. A volume of acoustic coupling fluid is positioned in the gel enclosure, which is fluidly connected to a vacuum pump. The vacuum pump draws air bubbles out of the gel enclosure to reduce attenuation of shock waves.

Abstract: A customer exercise reward method includes measuring work done by a customer and pushing a shopping cart through a store. At a check out location in the store, a customer reward is determined proportional to the work done. An amount due by the customer to the store for items brought by the customer from item locations in the store to the check out location is determined. At least a portion of the customer reward is redeemed by reducing the amount due.