Abstract: Cells in a population labelled with a lipid soluble fluorescent dye and excited with a beam of polarized light can be classified according to the distribution of the state of polarization of fluorescence emitted by a cell. The intensities of fluorescence, polarized in directions parallel and perpendicular to the direction of polarization of the excitation beam, are measured simultaneously to obtain the state of polarization.The state of polarization, so determined, bears a functional relationship to the fluidity of the plasma membrane of the cell and is thus a measure of the cell's function. Consequently, classification of cells in a population by the distribution of the state of polarization of the fluorescence emitted in response to their excitation enables different types of cells to be distinguished according to biological function. For example, white blood cells can be differentially analyzed using the method of the present invention.

Abstract: A hydraulic motor comprising a cylinder, a stepped piston reciprocatable in said cylinder and having relatively proportioned leading and trailing surfaces, the surfaces together with axially directed surfaces defining, with the cylinder walls, first, second and intermediate cylinder zones, which intermediate cylinder zone is sealed with respect the first zone, valve controlled inlet and outlet of said cylinder in communication with said first zone, a water inlet of said cylinder in communication with the intermediate zone, piston wall portions defining a cylindrical recess opening out into the second zone and passages serving to effect communication between the recess and the second and intermediate zones, a tubular spool valve rod, apertured adjacent one end thereof and formed adjacent an opposite end thereof with a pair of axially spaced apart flanges fitting slidingly into the cylindrical recess, the rod having formed thereon an outwardly directed abutment located intermediate the flanges and the one end o

Abstract: A hybrid power system comprising a pair of energy converters operating on a closed Rankine cycle, each energy converter having a vapor generator for vaporizing a high molecular weight working fluid in response to heat furnished from a burner associated with the generator, a turbo-generator responsive to vaporized working fluid for generating electrical power, a condenser responsive to the exhaust vapors from the turbo-generator for converting such vapors into a condensed liquid, and means for returning the condensed liquid to the vapor generator; sensors for sensing the electrical output of the turbo-generator of each converter; and a control system responsive to the sensors for controlling the burners in the converters so that each converter furnishes about half the electrical load on the system in normal operation thereof; one of the converters, termed the primary converter, operating with a working fluid having a higher boiling point than the working fluid in the other converter which is termed the seconda

Abstract: Radiation imaging apparatus includes a scintillation crystal responsive to radiation stimuli for producing light events, and a plurality of photodetectors arranged in a predetermined array relative to the crystal, each of the photodetectors having a light-sensitive surface facing the crystal and being responsive to a light event for producing an output signal. Coupling means associated with each photodetector applies its output signal to coordinate computing circuitry which computes the coordinates of a light event from signals applied thereto.In one embodiment of the invention, at least one of the coupling means includes a threshold linear gate for applying the output of the photodetector with which the coupling means is associated, to the coordinate computation circuitry only if the input to this particular photodetector exceeds a predetermined threshold.

Abstract: Coordinates of a light event, computed by signal processing equipment from output signals developed by an array of photodetectors of radiation imaging apparatus in response to the interaction of a radiation stimulus with a scintillation crystal, are validated only if a representation of the total energy of the light event lies within an energy window functionally related to the coordinates of the light event. In this manner, only desirable radiation stimuli interacting with the crystal are detected, and undesirable, indirect or scattered radiation stimuli interacting with the crystal are discriminated against.

Abstract: Processing an input audio-frequency analog signal, for example, speech, which is to be passed through a communication channel, includes performing an n-level digitizing of the input signal, transforming the levels of the digitized signal to other levels using a pre-selected n-bit transformation code, and converting the transformed digitized signal into analog form that is scrambled with respect to the input signal for transmission through the communication channel. At the receiving end of the channel, an n-level digitizing of the transmitted signal is performed, followed by an inverse transformation of the levels of the digitized signal using the inverse of the pre-selected transformation code used on the digitized input signal. The inversely transformed signal is then converted into an analog signal which is representative of the input signal.The communication channel can be an acoustic medium, a telephone line, or a CB radio link.

Abstract: Perinatal lung maturity is evaluated by determining the fluorescence polarization of a sample of pulmonary effluent containing pulmonary surfactant labeled with a fluorescent dye. The sample is excited with polarized radiation for causing the dye to fluoresce. I.sub.81 and I.sub.195, the intensities of fluorescence polarized in directions parallel to, and perpendicular to, the direction of polarization of the excitation radiation, are measured. From these measurements, the fluorescence polarization P, where P = (I.sub..parallel. - I.sub..perp.)/(I.sub..parallel. + I.sub.195), is determined. The value of P, which is functionally related to the microviscosity of the constituents of the surfactant, has been found to decrease with perinatal lung maturity. When the sample is amniotic fluid containing fetal pulmonary effluent, the evaluation of lung maturity can be carried out antepartum. Postpartum evaluation can be carried out by sampling neonatal tracheal or pharyngeal aspirates.

Abstract: A long term storage system comprising:Conduit means for supplying an inert gas;A plurality of long term storage containers adapted to be filled with an atmosphere of said inert gas and a fluid flow pathway serially interconnecting said conduit means with said long term storage containers for providing a continuous or intermittent supply of said inert gas thereto.

Abstract: A scintillation camera has a planar scintillating crystal that produces light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli causing such events, and a plurality of photomultipliers having photocathodes for receiving light from the crystal through a planar face thereof. Computing circuitry coupled to the photomultipliers computes the projection of a light event in the crystal on a reference axis by forming an analytical function of the outputs of the photomultipliers according to the spatial location of the light event in the crystal.

Abstract: An emitter unit comprises a pair of casing components and a coupling for coupling said components together via an interposed strip that extends beyond the components on all sides and is adapted to form a closed conduit such that one component is inside the conduit and one is outside. At least one of the components defines, together with the interposed strip, a flow restricting flowpath. Apertures are provided for effecting communication between said flowpath and the other component via said strip.

Abstract: A method for producing stimulated emission of radiation in the X-ray region comprising the steps of: selecting as an active medium a system having the following properties; two energy levels separated by an energy difference .DELTA.E corresponding to radiation of frequency .omega..sub.t in the X-ray region such that a transition from the upper to the lower of the two levels by one-photon emission is weakly allowed or strictly forbidden, one of the two levels having a nearly degenerate partner level optically coupled thereto such that a transistion therebetween by one-photon emission has a high probability; providing a resonator containing such an active medium; subjecting the active medium in the resonator to stimulating radiation at a frequency .omega..sub.1 that is preferably, substantially equal to the frequency of the optical coupling between the nearly degenerate levels but much smaller than the frequency .omega..sub.

Abstract: Apparatus for spraying trees and especially citrus trees comprising a mobile source of pressurized air adapted to be propelled along a path parallel to a row of trees to be sprayed; at least one nozzle connected to the source and having a throat in the form of a vertically oriented slip producing a sheet-like air blast whose principle plane is substantially vertically oriented; means associated with the list of oscillating the principle plane of the air blast about a substantially vertical axis through such an angle and at such a frequency as to impart an oscillatory movement to the leaf structure within the air blast thereby exposing each surface of the leaves to the blast; and a sprayhead associated with each nozzle out of the path of the air blast for spraying atomized liquid into the air blast at a location downstream of the throat.

Abstract: By identifying and analyzing the properties of the parameters of an input signal that contains speech in the presence of simultaneously occuring near-stationary noise, pauses between speech intervals as well as the termination of such noise can be recognized. When a pause interval containing noise is recognized, the parameters identified during such interval are used to set the parameters of an adaptive filter through which the input signal is passed during subsequent intervals of speech and until the noise terminates. During the time the input signal passes through the filter, the near-stationary noise is filtered out. In response to recognition of the termination of noise, the input signal is caused to by-pass the filter which is then prepared to accept the parameters of noise occuring in a subsequent pause.

Abstract: A pipe coupling suitable in particular for coupling a pipe of plastic material to a fitting or coupling together a pair of such pipes. The pipe coupling comprises an externally threaded sleeve member formed with one or more inwardly directed protrusions and adapted to receive a pipe to be coupled, an internally threaded collar member into which said sleeve is screwable, at least one of said members being formed or provided with constraining means whereby, with said pipe received within said sleeve the axial movement of said sleeve into said collar results in the protrusions biting into the pipe.

Abstract: A device for calibrating an instrument that measures circular dichroism has a transparent dielectric plate rotatably mounted in a framework so as to be rotatable about an axis passing through the plate substantially normal to the main irradiation direction, and means for indicating the angular position of the plate relative to its axis of rotation. A quarter-wavelength plate is mounted on the framework spaced from the dielectric plate with a surface normal to the irradiation direction.

Abstract: A head for a scintillation camera has a planar scintillating crystal that responds to radiation stimuli by producing light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli, and a plurality of photomultipliers each having a photocathode facing the crystal and producing an output signal when a light event occurs. The photomultipliers are organized into a first group arranged in a cluster centrally positioned relative to the crystal and having smaller photocathodes than those in the second group which is arranged in an annular array surrounding the first group. The head of the camera is connected to signal processing circuitry for computing each of two spatial coordinates of a light event by forming analytical functions of the output signals. Such circuitry has two selective modes of operation.

Abstract: An educational board game comprising single and multiple unit tokens respectively, marked with numerals corresponding to the number of constituent units, each multiple unit token being formed of a corresponding multiple of integrally coupled together single unit tokens, and a board formed with successive series of discrete engagement locations, each token being engageable with a number (corresponding to the number of constituent units thereof) of successive locations, successive series of locations being separated from each other.

Abstract: A detector for detecting phase-asymmetry in connection with a three-phase rotary machine includes a sensor couplable to the machine for picking up a signal associated with the leakage field during rotation of the machine. Circuit means are also provided for amplifying characteristic components of the signal (i.e., components whose amplitudes greatly increase relative to other components when phase-asymmetry occurs) and for attenuating other components of the signal, particularly at frequencies around f and 3f where f is the line frequency. Converter means converts the output of the circuit means into a control voltage, and control means are responsive to increases in the control voltage above a predetermined level established in the absense of phase-asymmetry for producing an output signal indicative of phase-asymmetry.

Abstract: A video-display processor produces an on-line display of the distribution density of radiation stimuli emitted by a radiation field utilizing a probe for detecting the stimuli and a counter for accumulating the number of stimuli detected; and motorized means to cause the probe to traverse the field and sequentially scan a preselected number of elemental areas, each having a preselected size, for causing the probe counter to accumulate the number of stimuli that occurred during the scan of each elemental area. The number of stimuli accumulated during the scan of each elemental area, upon the completion of the scan thereof is transferred into a memory whose contents modulate the picture elements of a raster generated by a CRT of a TV display thus displaying the density of each elemental area immediately after scanning thereof is complete.

Abstract: An irrigation dripper unit for use in irrigation in association with an irrigation supply pipe and also, when combined with a supply pipe, to form together with the supply pipe an integral unit. The dripper unit can be connected in series with the supply pipe or, when constituting a part of the integral unit, is connected in series with the supply pipe and has means to tap off a portion of the water flowing through the unit and to discharge such portion at a low drip rate.