Abstract: Disclosed is an optical waveguide fiber preform which is an assembly of one or more core rods surrounded by a plurality of clad rods. The clad rods have a central portion and a surrounding layer, in which the refractive index of the central portion is lower than that of the surrounding layer. The preform is drawn into an optical waveguide fiber that has a two component clad layer. Proper choice of the central portion and surrounding layer provide a waveguide fiber that is endlessly single mode. Alternative embodiments include fibers containing dopants that enhance fiber photosensitivity or which provide stress-induced or asymmetric-refractive-index-induced birefringence in the waveguide fiber.

Abstract: A printing process prints a continuously moving substrate with elongate, semi-tone graphics. The printed substrate is incorporated into a composite elastic material, in which the substrate is contracted, thereby forming a desired full-tone graphic from the semi-tone graphic.

Abstract: A trolley pole support apparatus is provided in which the trolley pole is urged to an extended position by a spring acting against a moment arm and the force required to position the trolley pole in the stowed position is minimized by minimizing the moment arm between the spring contact point and the trolley pole pivot. By doing so, even with the maximum compression of the spring in the stowed position, this small moment arm permits only small forces to be transmitted to the trolley pole shoe.

Abstract: A portal apparatus for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow.

Abstract: An electrical connector header assembly adapted for mounting on a printed circuit board so as to allow multi-directional mating contact with a complementary connector receptacle assembly includes a box-like insulated housing with contact receiving cavities therein. Each of the cavities is generally planar and is open to the front, rear and bottom surfaces of the housing, with the main portions of the cavities being parallel to each other and to the lateral surfaces of the housing. Each cavity also has a second, subsidiary, portion extending laterally from the main portion and open to the rear surface. The assembly further includes electrical contacts received in respective ones of the cavities. Each of the contacts is generally planar so as to fit within the planar cavity except for the laterally bent tab which extends into the cavity second portion. Each contact has a forward blade portion which extends beyond the front surface of the housing and which also extends beyond the bottom surface of the housing.

Abstract: The invention relates to a method of improving the quality of potatoes stored at reduced temperatures and a method of prolonging dormancy of stored potato tubers, by increasing the level of ADPglucose pyrophosphorylase enzyme activity within the potato tuber during storage at ambient or reduced temperatures. Novel DNA molecules, plant cells, and potato plants are provided which contain the gene for the ADPglucose pyrophosphorylase enzyme.

Abstract: In a video disc system for recovering prerecorded signals from a disc record by a signal pickup including a turntable, turntable drive means, and turntable speed adjusting means, a turntable speed control system is provided for maintaining the rotation of the turntable at a predetermined speed. Means responsive to the rotation of the turntable generate sample pulses having a frequency which is a function of the actual speed of rotation of the turntable. The sample pulse occur at a predetermined frequency when the turntable is rotating at the predetermined speed. Means are employed for generating a sawtooth-shaped reference wave having a frequency which is a multiple of the predetermined frequency. A sample-and-hold circuit is coupled to the sample pulse generating means and reference wave generating means for determining the magnitude of the reference wave during the occurrence of each of the sample pulses for developing a speed error correction signal.