Abstract: A spatial filter system for filtering a matrix of data values by an m.times.n matrix, where the m.times.n matrix is the product of a 1.times.n matrix and a m.times.a matrix. The system includes a first spatial filter adapated to filter each row of the data matrix with the 1.times.m matrix to provide a first filtered value matrix. The system also includes a second spatial filter adapted to filter each column of the first filtered value matrix with the m.times.1 matrix to provide a second filtered value matrix.

Abstract: A crosslinking reagent consisting of a first functional group capable of forming a covalent derivative with a material of interest; a second functional group capable of forming an in situ bond to a neighboring material upon activation; a cleavable bond separating said first and second groups; and a radioactive marker to identify the neighboring material after cleavage of said bond, whereby in situ protein interactions can be studied.

Abstract: Monoclonal antibodies, and a cell line characterized by its production of such monoclonal antibodies, demonstrating specific reactivity to an antigenic determinant possessed by a plurality of types of adenoviruses, a method of isolating such cell lines, and the use of such antibodies for diagnostic and therapeutic purposes as well as for identifying chemical compounds with similar properties, are disclosed.

Abstract: A method and apparatus for determining the distribution of a position-emitting radioisotope into an object, the apparatus consisting of a wire mesh radiation converter, an ionizable gas for propagating ionization events caused by electrodes released by the converter, a drift field, a spatial position detector and signal processing circuitry for correlating near-simultaneous ionization events and determining their time differences, whereby the position sources of back-to-back collinear radiation can be located and a distribution image constructed.

Abstract: A tissue-equivalent, useful in the treatment of burns or other skin wounds and in the fabrication of prostheses, is disclosed which is prepared from a hydrated collagen lattice contracted by a contractile agent, such as fibroblast cells or blood platelets, to form tissue-equivalent. In one embodiment, a skin-equivalent can be fabricated by growing a layer of keratinocyte cells thereon. Both the keratinocyte cells and contractile agent may be derived from the potential recipient of the skin-equivalent.

Abstract: A bone-equivalent, useful in the fabrication of prostheses, is disclosed which is prepared from a hydrated collagen lattice contracted by fibroblast cells and containing demineralized bone powder.

Abstract: Macroscopic divinylbenzene gels are provided having a high concentration of chemically accessible free vinyl groups. The gels are prepared in a mixture of nonpolar and polar solvents and in the presence of a polymerization initiator under conditions to eliminate syneresis.

Abstract: A preceramic polymer which is a polysilazane is described. It is made by reacting an organodihalosilane with ammonia to form an ammonolysis product, and treating the ammonolysis product with a basic catalyst capable of deprotonating an NH group that is adjacent to an SiH group to form said polymer. The polymer is preferrably further treated with an electrophilic reagent. These polymers are useful for making various ceramic products.

Abstract: Disclosed is a process for forming a new group of cobalt-based alloys containing 3-18% hafnium carbide (HfC), the HfC having a particle size finer than about three microns. The class of alloys exhibits excellent tensile strength characteristics at very low temperatures, exhibits very good time-temperature stability, and shows excellent oxidation characteristics even at temperatures above about 1000.degree. C. In addition, the alloy is attractive for use in the wrought state because of its ductility and low-temperature toughness characteristics.

Abstract: A microchannel spatial light modulator that has a photocathode to receive incident light and to provide a spatial distribution of photoelectrons (herein called an electron image) whose spatial number density is proportional to the spatial intensity of the incident light. A microchannel plate is provided to receive the photoelectrons and to amplify the electron image. An electro-optic plate is provided to receive the amplified electron image; there is a dielectric mirror coating and an insulating light-blocking layer at one major surface thereof to receive the electron image and a transparent electrode at the other major surface thereof for biasing purposes. All of the foregoing elements are contained within a vacuum housing; suitable electrical potentials are applied to effect the necessary results. The modulator is capable of real-time phase or intensity modulation.

Abstract: A process for entraining dislocations and other crystalline defects in a thin film includes coating a substrate, such as a layer of thermally grown silicon dioxide on a silicon wafer with the thin film of polycrystalline or amorphous silicon in the thickness range 0.05-10.mu. deposited by chemical vapor deposition. An encapsulation layer that is a composite of 2 .mu.m thickness SiO.sub.2, 30 nm of Si.sub.3 N.sub.4 is deposited on the thin film. A pattern of stripes is created on this encapsulation layer made of materials, such as titanium, silicon, silicon dioxide and photoresist. A long and narrow molten zone is created in the film with its long axis oriented perpendicular to the lines and is moved with a movable strip-heater over in a direction parallel to the lines in the recrystallization process to establish the dislocation and other crystalline defects in the film entrained to follow the pattern of stripes at locations related to the stripes.

Abstract: The potassium salt of phosphoenolpyruvic acid (PEP-K), used as a phosphorylation agent particularly in enzymatic reactions, is prepared by a process which consists of two steps, namely the treatment of a halopyruvic acid with a trialkyl phosphite and the hydrolysis of the dialkyl phosphate of enolpyruvic acid thus formed in an aqueous medium and in the presence of potassium hydroxide.

Abstract: An external cavity semiconductor laser includes an array of semiconductor optical gain elements, each device having at least one transmissive facet along an optical axis, and reflectors for reflecting incident light from the laser devices back to those devices. Optical fibers couple the transmissive facets of the optical gain elements in parallel to the reflectors. A spatial filter in the cavity between the optical gain element array and the reflectors establish spatial coherence of the light within the cavity to establish a coherent output beam. In this form, the fiber-coupled laser devices may be located in remote sub-groups, thereby reducing the power dissipation density for the external cavity laser.

Abstract: An underwater arc stud welding system consists of a specially designed submersible stud welding gun which is connected, by means of an electrical umbilical to conventional stud welding equipment located out of the water. The stud gun employs a simple, corrosion resistant, stud lifting mechanism with only one moving part, which freely floods with water and thereby eliminates problems associated with increased ambient pressure and also employs a magnetic base and a grounded electrical safety shield.

Abstract: Cataract formation in mammalian lenses can be prevented or reversed by applying a solution of an aldehyde, an acrylamide or a glycol to the lens under conditions that permit the solution to interact with the lens constituents.

Abstract: A novel class of dialkyl and dialkyl-aromatic viologens (4,4'dipyridinium compounds) and their salts which may be polymerized and covalently bonded to electrodes for use in electronic display systems.

Abstract: Microcellular foam materials having void fractions of about 5 to 30 percent and uniform void sizes on the order of 2 to 25 microns are produced by pre-saturating the material to be processed with a uniform concentration of a gas while controlling temperature and pressure to avoid cell nucleation. Processing is also done under pressure to avoid nucleation. After processing, pressure is released and cell nucleation occurs at or near the glass transition temperature of the material; it is then cooled quickly to preserve the microcellular structure.

Abstract: The risk of ventricular fibrillation in animals is reduced by administering tyrosine, a tyrosine precursor, threonine or mixtures thereof, either alone or in combination with a substance which is known to reduce the risk of ventricular fibrillation. A novel composition is provided comprising a unit dosage form of tyrosine, a precursor for tyrosine, threonine or mixtures thereof and a substance which is known to reduce the risk of ventricular fibrillation.

Abstract: A method and apparatus is described wherein a buried double heterostructure laser device is formed utilizing epitaxial layers of quaternary III-V alloys of gallium indium arsenide phosphide and wherein the buried layer is formed by first etching the p-type top layer of the structure down to the quaternary active layer forming a mesa. A second etchant is then provided which preferentially etches the active layer. This etchant is used to undercut the top layer by removing the active layer on both sides of the top mesa surface providing a narrow strip of active layer underneath the undercut mesa. The undercut is then filled in by a heat treatment process which results in migration or transport of the binary top layer and binary bottom layer to fill in the undercut, leaving the active layer buried in the binary material. In an alternate embodiment of the invention, the two-step etching process plus the transport phenomena is utilized to form the mirror surface of a laser device.

Abstract: An improved method of removing pyritic sulfur and other contaminants from the coil in a coal-oil slurry. In such a slurry, raw pulverized coal is suspended in fuel oil. In practicing the process, the slurry is heated to a temperature of about 220.degree. C., at which temperature hexagonal pyrrhotite is converted to highly ferromagnetic monoclinic pyrrhotite which can be removed by a magnetic separator.