Abstract: A non-invasive device which determines the pulp oxygenation level of a tooth and the vitality of a tooth using multiple-wavelength optical plethysmography. A sensor is shaped to be mounted on a tooth and circuitry for processing a signal from the sensor and supplied from a photosenstive diode is used. The photosensitive diode in the sensor detects light scattered from the tooth which was emitted from red, green, and infrared LEDs. An electrocardiogram (ECG) monitor is provided so as to produce improved detection reliability by synchronous averaging using the occurrence of the R-wave of the ECG as a time marker. Using this approach, a threshold-of-detection criterion can be established based on an average computed over a period to achieve a desired signal-to-noise ratio.

Abstract: An apparatus for measuring the pressure-transmitting characteristics of a blood pressure cuff in terms of delivered cuff pressure. It consists of a somewhat flexible cylindrical supporting tube containing a non-compressible liquid, connected to a pressure transducer. The cuff is wrapped around the tube, and the remaining exposed area of the tube is covered by a rigid cylindrical tube to prevent bulging of the supporting tube when cuff pressure is applied thereto. The cuff is pressurized while simultaneously recording its pressure and the transducer detected pressure. The resulting X-Y curve is compared with one taken of the supporting tube alone.

Abstract: A flow indicating attachment for a transparent rotameter column containing a visible float movable in accordance with the rate of fluid flow through the column consists of a reciprocating scanner moving parallel to the column in a flow rate range including the range of float movement and coupled to a potentiometer forming a synchronous analog scanning signal which is furnished to a recorder. The scanner has a photoelectric float-sensing assembly including a photocell connected in the analog scanning signal circuit. When the sensing assembly is shaded by the rotameter float, it produces an abrupt dip in the recorded analog scanning signal, thus providing a recorded indication of the float's position in the range covered by the track of the reciprocating scanner.

Abstract: A tranquilizer dart for injecting a tranquilizing liquid into an animal consists of a cylindrical chamber with a tapered forward end provided with a pointed hollow needle. A conical valve bears against an annular seat in the chamber and has a triggering pin extending through the needle and normally projecting forwardly beyond its point. Tranquilizer liquid is contained in the chamber between the valve and a front plunger. A rear plunger is provided in the rear end of the chamber, and rearward movement thereof is limited by an insertable stop pin. The rear plunger serves, on loading, to compress the air between itself and the front plunger. Responsive to impact, the triggering pin is pushed back, unseating the conical valve, and the compressed air forces the front plunger forward, thus injecting the liquid into the animal.

Abstract: A blink-activated duct for supplying a solution to the eye of the user has a particular utility in introducing an artificial tear solution to the eye of those persons who are incapable of producing such a solution themselves. The duct consists of a reservoir section which contains the solution, and a pump section consisting of a contact lens or a Silastic tube assembly for delivering the solution directly to the eye. This pump section is activated by the eyelid compressing the contact lens or the Silastic tube assembly, causing the solution to be displaced to the eye and successively drawing additional solution from the reservoir section to the pump section due to the creation of a temporary vacuum.