Abstract: Disclosed herein are turbines and turbine systems that may be used to generate power and/or electricity from flowing water or may be used in various other applications such as the pumping of water. One embodiment of the disclosed turbines includes a plurality of blades that may be connected to a turbine housing by a hinge so that the blades are movable between an active state, wherein the blade is configured to contribute to the rotational movement of the turbine, and a passive state, wherein the blade is configured to minimally resist the rotation of the turbine. Turbine blades are disclosed with specific features that more efficiently capture water flow power.

Abstract: A plastic bite holder for securely holding a rigid cassette comprising a photoreceptor and a light proof cover for use as a dental x-ray imaging medium is described. The holder is molded into a single piece of polyethylene and has a tab onto which the patient bites, a backing plate and two gripping members for securely holding the cassette against the backing plate.

Abstract: This invention is a plastic holder for holding a rigid photoreceptor in the mouth during the creation of dental bitewing and periapical x-ray images, and more particularly is a one-piece plastic holder comprising (1) a bitewing holder comprising a backing plate, a tab and two gripping members for holding the photoreceptor in secure contact with the backing plate, (2) a periapical holder comprising a backing plate and a gripping member for holding the photoreceptor in secure contact with the backing plate, and (3) a handle in the form of a plastic strip connecting the two holders.