Abstract: The present invention relates to two ATP diphosphohydrolases ATPDase enzymes isolated from bovine aorta and pig pancreas, which enzymes have a molecular weight for their catalytic unit of about 78 and 54 Kilodaltons, respectively. A novel process for obtaining a highly purified ATPDase is also an object of the present invention. This process has been successfully applied to the purification of both the pancreatic and the aorta enzymes and is deemed to work in the purification of any ATPDase. For both sources of enzymes, the process allows the specific activity of the enzyme to be increased by at least 10,000 fold when compared to the activity retrieved in the crude cell homogenates. The novel process involves an ion exchange chromatography step, a separation on an affinity column, followed by an electrophoresis under non-denaturing conditions.

Abstract: A codebook is searched in view of encoding a sound signal. This codebook consists of a set of pulse amplitude/position combinations each defining L different positions and comprising both zero-amplitude pulses and non-zero-amplitude pulses assigned to respective positions p=1, 2, . . . L of the combination, wherein each non-zero-amplitude pulse assumes at least one of q possible amplitudes. To reduce the search complexity, a subset of pulse amplitude/position combinations from the codebook is pre-selected in relation to the sound signal, and only this subset of combinations is searched. The pre-selection of the subset of combinations consists of pre-establishing, in relation to the sound signal, a function S.sub.p between the respective positions p=1, 2, . . . L and the q possible amplitudes, the search being limited to the combinations of the codebook having non-zero-amplitude pulses which respect the pre-established function.

Abstract: A codebook is searched in view of encoding a sound signal. This codebook consists of a set of codevectors each of 40 positions and comprising N non-zero-amplitude pulses assignable to predetermined valid positions. To reduce the search complexity, a depth-first search is used which involves a tree structure with levels ordered from 1 through M. A path-building operation takes place at each level whereby a candidate path from the previous level is extended by choosing a predetermined number of new pulses and selecting valid positions for said new pulses in accordance with a given pulse-order rule and a given selection criterion. A path originated at the first level and extended by the path-building operations of subsequent levels determines the respective positions of the N non-zero-amplitude pulse of a candidate codevector. Use of a signal-based pulse-position likelihood estimate during the first few levels enable initial pulse-screening to start the search on favorable conditions.

Abstract: A method of encoding a speech signal is provided. This method improves the excitation codebook and search procedure of the conventional Code-Excited Linear Prediction (CELP) speech encoders. This code is based on a sparse algebraic code consisting in particular, but not exclusively, of interleaving N single-pulse permutation codes. The search complexity in finding the best codeword is greatly reduced by bringing the search back to the algebraic code domain thereby allowing the sparsity of the algebraic code to speed up the necessary computations. More precisely, the sparsity of the code enable the use of a very fast procedure based on N-embedded computation loops.

Abstract: The present invention concerns efficient quantization of more than one LPC spectral models per frame in order to enhance the accuracy of the time-varying spectrum representation without compromising on the coding-rate. Such efficient representation of LPC spectral models is advantageous to a number of techniques used for digital encoding of speech and/or audio signals.

Abstract: A method for the preparation of insoluble hydrogels from the complexation of polycations and xanthan is reported. Stable hydrogels capable of retaining between 65 and 95 % weight water were prepared particularly with chitosan and xanthan. The water retention and properties of the hydrogels were studied as a function of the degree of acetylation of chitosan and the ratio chitosan/xanthan used in the preparation of the gel. The chitosan-xanthan complex was used to immobilize biological material. Hydrogels containing enzymes (for example endo-1,4-.beta.-xylanase and protease) either as single enzymes or as a binary system have been prepared. Immobilization varied between 85 and 98 % . The immobilized xylanase activity was significantly greater with respect to the free enzyme while the binary enzyme system promoted protease activity. Other hydrogels prepared with polybasic drugs complexed to xanthan with or without chitosan have been prepared.

Abstract: The plasma spray method produces a material deposit on a substrate to form either a protective coating of a near net shape body, or produces a powder of a given material. The material is supplied to a plasma discharge in the form of a suspension comprising small solid particles of that material dispersed into a liquid or semi-liquid carrier substance. The suspension is brought into the plasma discharge by an atomizing probe using a pressurized gas to shear the suspension and thus atomize it into a stream of fine droplets. The plasma discharge vaporizes the carrier substance and agglomerate the small solid particles into partially or totally melted drops which are accelerated to hit the substrate and form thereon the coating or near net shape body. Alternatively, the molten drops can be solidified in-flight and collected into a vessel to produce a powder of that material.

Abstract: A liquid film stabilized induction plasma torch comprises a cylindrical torch body made of cast ceramic or polymer-matrix composite, a coaxial cylindrical plasma confinement tube mounted inside the torch body, a gas distributor head secured to one end of the torch body to supply the confinement tube with gaseous substances, a cylindrical and coaxial induction coil embedded in the ceramic or polymer-matrix composite of the torch body, and a thin annular chamber separating the coaxial torch body and confinement tube. A high velocity cooling liquid flows through the thin annular chamber. The confinement tube is made of porous ceramic material through which cooling liquid from the annular chamber permeates. The permeating cooling liquid forms on the inner surface of the confinement tube a thin liquid film subjected to the high temperature of the plasma produced in the confinement tube.

Abstract: The disclosure herein describes a cut and strip tool to assist in the stripping of insulation from one or more insulated conductive wires; it comprises a pair of handles which are equipped, at their upper part, with an elongated wire receiving element including, at one end thereof, a cutting tool for completely severing the wire and, at the other end, a pair of wire receiving blades which make an incision in the insulation of the wires as they are inserted in the blades and which, upon actuation of the handles, initiate removal of a portion of the insulation so that the total effort for a complete insulation stripping operation is greatly reduced with the present tool as compared to that of conventional tools as a result of this initial insulation removal carried by the tool rather than by the operator.

Abstract: The present invention relates to a naturally occuring, isolated and characterized microorganism producing hydrolase enzyme, specifically, chitosanase; chitosanase isolated thereof; the nucleic acid sequence of the portion of the gene encoding this chitosanase; complete amino acid sequence of this chitosanase; hybrid plasmids containing the related gene; host microorganisms transformed with the plasmids; recombinant microorganisms overexpressing the enzyme; and to enzymatic treatment of chitosan with the aforementioned enzyme resulting in molecular weight decrease, viscosity decrease and increase of solubility of chitosan in water.

Abstract: A method of encoding a speech signal is presented. This method improves the excitation codebook and search procedure of the conventional Code Excited Linear Prediction (CELP) speech encoders. Use is made of a dynamic codebook (201, 202) based on the combination of two modules: a sparse algebraic code generator (201) associated to a filter (202) having a transfer function varying in time. The generator (102) is a structured codebook with codewords having very few non zero components. The filter (202) shapes the spectral characteristics whereby the resulting excitation codebook (201, 202) exhibits favorable perceptual properties. The search complexity in finding the best codeword is greatly reduced by bringing the search back to the algebraic code domain thereby allowing the sparsity of the algebraic code to speed up the necessary computations.

Abstract: The present invention relates to a method of instrumenting an already erected concrete or rock structure in order to determine the state of deformation of that structure. A cylindrical inclusion made of concrete having substantially the same mechanical properties as the concrete or the rock of the structure is inserted into a hole drilled into the concrete or rock. Sensors capable of detecting deformations are embedded in the concrete of the inclusion. The empty space between the inclusion and the hole is tightly filled with a grout whereby any deformation of the concrete or rock structure also deforms the inclusion and is therefore detected by the sensors embedded therein. The invention also extends to the inclusion and the so instrumented concrete or rock structure.

Abstract: The method and apparatus treat a surface of natural rock or artificial stone-like material to give to this surface an attractive finish. A high temperature jet of plasma and a high speed jet of cooling fluid are projected onto the surface to be treated. The two jets are moved on the surface at a given speed with the jet of cooling fluid following the plasma jet. The speed of movement is selected so that the high temperature plasma jet heats only a thin superficial layer of rock or stone-like material. As the jet of cooling fluid follows the jet of plasma, it suddenly cools the thin superficial layer just heated by the plasma jet to cause a thermal shock which bursts particles of rock or stone-like material at the surface thereof, and blows these particles off the rock surface.

Abstract: A high performance induction plasma torch comprises a cylindrical torch body made of cast ceramic or composite polymer, a coaxial cylindrical plasma confinement tube located inside the torch body, a gas distributor head secured to one end of the torch body to supply the confinement tube with gaseous substances, a cylindrical and coaxial induction coil completely embedded in the ceramic or polymer material of the torch body, and a thin annular chamber separating the coaxial torch body and confinement tube. This confinement tube can be made of pure or composite ceramic materials based on sintered or reaction bonded silicon nitride, boron nitride, aluminum nitride or alumina, or any combinations of them with varying additives and fillers. The annular chamber is about 1 mm thick and high velocity cooling water flows therein to efficiently cool the plasma confinement tube.

Abstract: A pressure-molded, rigid, high surface cathodic or anodic electrode of low electrical resistance and good mechanical strength and resistance to corrosion comprising non-dissolving, electrically-conducting metal particles of high specific surfaces and fractal structure which are bound with up to 15% by weight of aluminum phosphate.

Abstract: The invention relates to a process and an apparatus for the plasma deposition of protective coatings and near net shape bodies using induction plasma technology. The apparatus comprises an induction plasma torch in which the particulate material to be deposited is accelerated and injected axially into the discharge. As the particles traverse the plasma they are heated and melted before being deposited by impaction on the substrate placed at the downstream end of the plasma torch facing the plasma jet.

Abstract: The present invention relates to a scintillation detector for a tomograph comprising at least two scintillators having different scintillation characteristics and being optically coupled to a photodetector.

Abstract: The present invention relates to an improved process for the wet oxidation of water soluble organic pollutants or of an aqueous suspension of organic pollutants. In the contacting of an oxidizing gas and a polluted aqueous phase, the improvement comprises forming a fine mist of the polluted aqueous phase in the presence of the oxidizing gas, thereby increasing the interfacial area between the gas and the polluted aqueous phase. Then the formed mist is introduced into a heated reaction chamber under pressure, thereby enhancing the rate of the destructive oxidation of the organic pollutant by the increase in mass transfer between the gaseous phase and the aqueous mist, the reaction temperature being selected to favor rapid destruction of the pollutant without the formation of stable intermediate reaction products. After destruction of the pollutants, the reaction mixture is allowed to flash off at a pressure lower than the reaction pressure.

Abstract: The present invention relates to a process for continuous conversion of starch or starch containing materials into hydrolysates such as dextrins, higher sugars, maltose or dextrose. It provides for an extremely fast heating of an acidified or non acidified slurry by spraying it very finely into a chamber containing steam under pressure. The fast heating rate combined with the high operating temperature allow processing times of less than 20 seconds, usually between 1 and 4 seconds during which the starch is converted into the desired hydrolysate without passing through the classical "gelatinized" or "pasted" state. The desired product can be custom tailored from dextrins to glucose, in high yield and low level of degradation products. Moreover, the dextrins so produced have a very uniform molecular weight and the process can handle purified as well as impure starch such as ground corn, cassava and deteriorated harvests.

Abstract: The present invention relates to a method and apparatus for providing a magnified image of a zone of a specimen. The method comprises the steps of generating acoustic waves having different frequencies and focussing on the zone the acoustic waves wherein different points on the zone receive and reflect acoustic waves having different frequencies, the frequency of a wave received by a given point being function of the position of the point in the zone. The method further comprises the steps of analyzing the reflected waves to generate signals representative of the physical structure of the zone at the points and establishing a correspondance between the signals and the positions of the points in the zone from the frequencies of the reflected waves and, forming from the signals a magnified representation on a display of the physical structure of the zone to construct an image of the zone.