Abstract: A fencing sports wheelchair includes a seat (1) mounted to a base (2). A pedestal (3) underlying the base such that the base is selectively rotatable. A platform (10) having an upper surface to which the pedestal is affixed and having a lower surface. At least three wheels are mounted to the platform so that the wheels extend beneath the lower surface of the platform. In addition to a lever means for converting single-handed manual motion into forward and backward translation of said platform.

Abstract: An implantable ventricular assist device is described which has only one moving part. This part consists of a conical rotor with vanes which spiral upward from the base in a direction opposite to the direction of rotation. There are no valves within the device itself, but one or two valves are situated in the conduits connected to it. The device is powered by a constant running electric motor which screws into the base of the rotor housing. The motor is connected to a portable external battery by means of subcutaneous electrical leads.

Abstract: Semiconductor devices such as lasers which include a substrate with a channel therein with a clad layer overlying the substrate and filling the channel exhibit irregularities such as terraces in the surface of the clad layer which are detrimental to device performance. These irregularities are substantially eliminated by forming the channel in a surface of a buffer layer greater than about 4 micrometers thick on the substrate and forming the clad layer over the buffer layer and the channel. CW lasers incorporating the principles of the invention exhibit the highest output power in a single spatial mode and maximum output power which have been observed to date.

Abstract: A method is disclosed for recording information wherein an information-containing surface relief image is mechanically micromachined into a recording medium formed of a copper/oxygen amalgam containing 8 to 11 atomic weight percentage of oxygen and having a grain size of 500 Angstroms or less and wherein the amalgam has a hardness of 250 to 320 on the Knoop hardness scale.

Abstract: Method and apparatus are provided for determining the diffusion length of minority carriers in semiconductor material, particularly amorphous silicon which has a significantly small minority carrier diffusion length using the constant-magnitude surface-photovoltage (SPV) method. An unmodulated illumination provides the light excitation on the surface of the material to generate the SPV. A manually controlled or automatic servo system maintains a constant predetermined value of the SPV. A vibrating Kelvin method-type probe electrode couples the SPV to a measurement system. The operating optical wavelength of an adjustable monochromator to compensate for the wavelength dependent sensitivity of a photodetector is selected to measure the illumination intensity (photon flux) on the silicon. Measurements of the relative photon flux for a plurality of wavelengths are plotted against the reciprocal of the optical absorption coefficient of the material.

Abstract: A layer of near stoichiometric magnesium oxide on a conducting substrate forms a dynode. The dynode is formed by preparing a layer of oxidized magnesium on a conducting substrate, heating the oxidized magnesium layer in a vacuum between about 400.degree. and about 500.degree. C., and treating the layer to render it more nearly stoichiometric. One method of treating the layer is to expose it to oxygen at about room temperature for about ten to twenty minutes at a pressure between about 10.sup.-6 to 10.sup.-5 torr. Another method of treating the layer is to impinge a noble gas, such as argon, at a pressure suitable for sputter etching, such as between 10.sup.-6 and 10.sup.-3 torr, to remove between ten and twenty atomic layers from the surface of the layer. The layer is then exposed to oxygen at room temperature for about ten to twenty minutes at a pressure between about 10.sup.-6 and 10.sup.-5 torr.