Abstract: Body surface potential map (BSPM) pace-mapping is a system and method that can be used in medicine to localize with precision the site of origin of abnormal cardiac electrical activity and to guide the positioning of a catheter over this site of origin, such as the site of ventricular preexcitation in patients with the Wolff-Parkinson-White syndrome or the focus of ectopic activity in patients with tachycardia. Body surface potential distributions are measured with a large number of electrodes, e.g. 24 to 128, distributed over the entire torso surface. The electrical signals are first amplified, converted into digital data and treated to remove electrical or muscle artifacts. Data recorded during abnormal activation (reference beat) are aligned with data recorded during cardiac pacing (paced beat) so as to maximize the average value of the correlation coefficient between the reference and the paced potential distributions during a preset time interval following the beginning of the QRS complex.

Abstract: The invention relates to polycomponent electrocatalysts suitable for use at the cathode of electrochemical and fuel cells. More particularly, the invention relates to a polycomponent electrode comprising a catalytic electrode including a mixture of a metallic component including at least one metal selected from palladium, platinum, ruthenium, rhodium, iridium or osmium and a chemical component including at least one compound selected from the group consisting of suitable oxometallates and metallic acids. Preferably, the metallic component comprises at least one metal selected from the group consisting of platinum and palladium and the chemical component comprises at least one compound selected from the group consisting of tungstic acid, molybdic acid, ammonium tungstate, ammonium molybdate, sodium tungstate and sodium molybdate. The electrode is operable in fuel cells which employ readily available oxygen or air.

Abstract: A source of microwave power is connected to the first, input, port of a six-port device whose second, output, port is connected to a device under test. A variable impedance is connected between the source and the input port. Preferably, the variable impedance is a mechanical three stub tuner. The six-port device includes a first directional coupler whose first input comprises the input port and whose first output comprises the output port. First, second and third hybrid couplers have outputs which constitute the third, fourth, fifth and sixth outputs of the six-port device. A power divider connects the directional coupler to the hybrid couplers.

Abstract: An electrode balloon for use in anatomical cavities, such as cardiac chambers, to pick up bioelectrical signals from the walls thereof simultaneously in a multitude of sites for the mapping of the activation potentials thereof comprises an inflated tight rubber balloon having an opening at a proximal end thereof communicating with a filling tube which defines apertures for dispensing fluid in the rubber balloon. An extensible knitting which covers the rubber balloon is provided with a plurality of electrode heads distributed thereon to contact the walls of the cavity when the rubber balloon is inflated by a fluid conveyed therein through the tube. Insulated electrical conductors connect the electrodes to a signal recording and processing device.

Abstract: The thermometer consists of an operational amplifier ratio bridge which is made up of at least one arm having a 3-terminal high impedance temperature sensor one of whose leads being connected to the output of an operational amplifier whose gain has been stabilized and whose output impedance has been rendered negligible by negative feedback. The other lead being connected to the input of an operational amplifier whose gain has been stabilized and whose input impedance has been rendered negligible by negative feedback. Standard arms, comprising standard resistors and capacitors and operational amplifiers whose gain has been stabilized by negative feedback may be connected in parallel with the first arm.

Abstract: The optical waveguide coupler device is formed on two laterally adjacent optical fibers for splitting with wavelength-flattened ratios an incident light intensity into the two fibers. Adjacent sections of the two fibers are fused together and first and second concatenated tapered portions are formed. These two tapered portions are separated by a central optical waveguide portion including two parallel branches of slightly different lengths, each capable of propagating a light signal from either tapered portion to the other. The first and second tapered portions define optical waveguide couplers presenting coupling ratios varying with optical wavelength in accordance with different curves. The different lengths of the two parallel branches of the central portion cause a shift .phi. between the phases of the optical signals propagating through these two branches. The coupling ratios of the tapered portions and the phase shift .phi. are selected to wavelength-flatten the coupling ratios of the coupler device.

Abstract: Hypochlorite digestion of bacterial biomass to recover intracellular poly-.beta.-hydroxylalkanoic acid (PHA) has not been used on a large scale since it has been widely reported to severely degrade the polymer. The process of the invention proposes to optimize the initial biomass concentration, the digestion time and pH of the hypochlorite solution to minimize degradation. Consequently, PHA of up to 95% purity with an average molecular weight of 600,000 can be recovered from biomass initially containing PHA having a molecular weight of 1,200,000. By incorporating a pretreatment step with an anionic surfactant solution, PHA of 99% purity with a molecular weight of 1.20.times.10.sup.6 was obtained from biomass containing 57% PHA by weight with an initial molecular weight of 1.25.times.10.sup.6.

Abstract: Apparatus and method for comparing a test handwriting signature with a reference signature where each of the test and reference signatures have been acquired by generating three electrical digital position signals characterizing a trajectory of a handwriting signature. The apparatus comprises a device for calculating variations of simple dynamic parameters of the test signature with respect to the simple dynamic parameters of the reference signature, by calculating a first evaluating function C1; a device for comparing C1 with a first threshold value, and rejecting said test signature if C1 passes the first threshold value; a device for calculating local intrinsic correlations of V.sub..sigma. and V.sub..theta.

Abstract: The present disclosure describes an optical waveguide device and a method for making such device. The device comprises a substrate; a waveguide embedded in the substrate, the waveguide having a refractive index higher than the refractive index of the substrate; and first and second optical mirrors placed respectively in two different positions along the waveguide. The method comprises steps of (a) cleaning a substrate by means of a cleaning agent; (b) embedding a waveguide in the substrate; and (c) placing first and second optical mirrors respectively at two different positions in the substrate, the steps (b) and (c) being performed in such a manner that the mirrors being positioned along the waveguide.

Abstract: The apparatus and method for digitizing and segmenting a handwriting movement comprises an electrical transducer for generating three electrical digital position signals characterizing a trajectory of the handwriting movement. The apparatus comprises a device for low-pass filtering the electrical signals; a device for deriving the electrical signals by predetermined time and transfer functions for generating V.sub.x and V.sub.y electrical components which represent respectively speeds of the point according to X and Y axes of a cartesian reference; and a device for calculating V.sub..sigma. and V.sub.74 values from the V.sub.x and V.sub.y values. The apparatus also comprises a device for calculating handwritten components and handwritten strings, where each of the handwritten components is delimited by two successive liftings of the point along the trajectory, and each of the handwritten strings is delimited by two successive portions of the trajectory where the V.sub..theta.

Abstract: At least two three-phase transformer arrangements include a plurality of primary windings connected in a wye configuration and at least two converter arrangements, each converter arrangement comprising a plurality of secondary windings connected in a double-wye configuration. A separate rectifier is connected in series with each secondary winding of each converter arrangement.

Abstract: A method and device for determining in-situ rheological properties of earth materials are disclosed. A low-angle cone penetrometer is pushed into a predrilled cylindrical pilot hole of smaller diameter, to cause enlargement of the pilot hole. In one embodiment, the load applied to the cone is held constant and the relationship between the cone penetration and the time is recorded. In another embodiment, either the load on the cone or the rate of penetration into the pilot hole is held constant and the relationship between the penetration or the penetration rate and the resistance of the material against the enlargement of the pilot hole is recorded. The rheological properties of the material, such as the creep and time or rate-dependent deformation and strength properties, are then deduced from the recorded data.

Abstract: A method and an apparatus for impregnating one side of a porous board, such as gypsum boards, with a precise amount of compatible phase change material. A predetermined amount of the phase change material is applied at a predetermined uniform rate to the one surface of the board so that a predetermined amount of the phase change is impregnated. The rate of application is lower than the absorption rate of phase change material. Also, the temperature of the board must be above the melting point of the phase change material during the impregnation. The process and apparatus may be either a continuous, a semi-continuous or a batch operation, and the resulting product is intended as a building construction material.

Abstract: A wavelength filter is integrated to a single-mode optical fiber capable of propagating a light signal and comprising a longitudinal and opaque outer jacket enveloping the fiber. This fiber is stripped of its jacket on a given length thereof to obtain a non-jacketed length of optical fiber. The so produced non-jacketed fiber length is formed with first and second concatenated biconical tapers separated from each other by a given distance and each having a given profile. By appropriately selecting the distance separating the two tapers and the given profile thereof, the filter will enable transmission of a first, predetermined wavelength of the propagated light signal while it will stop a second, predetermined wavelength of the signal. A method of integrating such a filter to a single-mode optical fiber is also proposed.

Abstract: A method and system for simultaneously detecting the amplitude and phase angle of harmonics in a periodic signal. A tunable tracking filter is connected to an input of the system to receive a periodic signal having a frequency within a predictable range. A conditioning circuit is connected to the input to tune the tracking filter to a selected harmonic in the periodic signal. A programmable frequency multiplier forms part of the conditioning circuit and is connected for locking the clock frequency of the filter to tune it to the selected harmonic of the periodic signal to provide at its output an output signal having the amplitude and corresponding phase of the selected harmonic.

Abstract: A bioreactor for the biochemical treatment of liquids containing organic matter, comprises an elongated, upwardly extending tubular container having inlet means for receiving the liquid to be treated and outlet means for discharging the treated liquid. A plurality of spaced-apart first and second trays are alternatively arranged above one another inside the container, each tray being apertured to provide liquid flow communication between the inlet and outlet means and adapted to support a respective bed of microorganism cells capable of reacting with the organic matter. The apertures of the first and second trays are arranged relative to one another to cause the liquid to flow laterally across the respective cell beds of the trays as the liquid flows from one tray to another.

Abstract: The continuous monitoring of an element in a molten substance containing same is effected by monitoring the electromotive force generated between a first electrode in contact with the substance and a second electrode in contact with a reference material which is separated from the substance by a solid electrolyte. The reference material comprises a metal and at least one salt selected from the group consisting of (a) a combined salt of the metal and a monovalent metal, (b) a mixture of a first salt of the metal and a second salt of the monovalent metal, the first and second salts having a common anion, (c) a mixture of the first salt and the combined salt, and (d) a mixture of the second salt and the combined salt, the at least one salt being present in the form of a slurry containing a liquid phase in equilibrium with a solid phase, the liquid phase containing the metal and monovalent metal in ionic form and the solid phase containing the first salt, second salt or combined salt.

Abstract: An extensometer for detecting traumatized ligaments where the elongation of the ligament is either abnormally large or abnormally small compared to the elongation measured on a healthy ligament for an angle of flexion of the knee. The extensometer includes at least one flexible member having a strain gauge secured thereto to measure deflexion of the flexible member from its normal configuration. The flexible member has a free end and is secured at its opposed end to a support base. A clamping member is provided to retain the free end of the flexible member on a ligament while maintaining the support base substantially stationary with respect to the ligament whereby elongation of the ligament is detected by the deformation of the flexible member from its initial configuration.