Abstract: Strain reduction or reversal technique for continuous casting of a metal billet element wherein there is provided an axial mold wall which is oscillatable, a plug element in the axial wall which may be solid in the sense that it closes one end of the mold or which may be of a type in which molten metal may flow therethrough into the mold, one of said elements being oscillatable with respect to the axial wall in a manner to relieve strain on metal newly freezing to the axial wall during oscillation of the axial wall.

Abstract: A flow-through test cell is disclosed which features an electrical conductor disposed in non-contacting adjacency with an ionic sensing electrode and a porous liquid junction for improving signal-to-noise ratio. The electrical conductor provides a low-impedance path through the fluid which effectively neutralizes signal distortion due to impedance variations in the air-segmented, continuously flowing stream. The electrical conductor includes distended sections which fixedly position such conductor in the ionic test cell, whereby shorting contact with said ionic sensing electrode and said porous liquid junction element is prevented.

Abstract: Biological fluids, such as serum, are analyzed for the presence, nature and/or amount of antibodies, antigens and antibody:antigen complexes therein using as a reagent, insolubilized rheumatoid factor or insolubilized C1q. These reagents are themselves novel. They bind to antibody: antigen complexes, but not to free antibodies or antigens, and complexes can thus be removed from mixtures thereof with other materials, such as antibodies and antigens.

Abstract: Method and apparatus suitable for automatic assay of fluid samples, particularly immunoassays, in which a reaction product of the assay is bound to a magnetically attractable particle and separated from the reaction mixture by use of a magnetic trap. The method and apparatus are of especial use in radioimmunoassays carried out in an automated continuous-flow manner.

Abstract: A method of determining Ab:Ag complex in a biological fluid sample comprising adding to the sample a solution of RF or Clq and a known quantity of a material, such as immunoglobulin-coated polystyrene particles, which is caused to agglutinate on contact with RF or Clq, and detecting the amount of material which is not agglutinated.

Abstract: A dilutor/dispenser system wherein a marker, e.g., an air bubble, is introduced at the probe inlet prior to each aspiration cycle, so as to be displaced along the probe system during such cycle. The location of the marker is detected at the end of the aspiration cycle, to indicate whether an appropriate liquid volume has been aspirated. The aspirated liquid, along with the marker and a predetermined volume of diluent, is subsequently dispensed. An alarm may be activated, if an improper volume has been aspirated.

Abstract: A metering apparatus is adaptable either as a dispenser or a sampler, the surface of the aspirating probe being coated with a thin film of liquid immiscible with the liquids to be aspirated. The thin immiscible film prevents contamination between segments of successively aspirated liquids and, also, their respective sources. Further, segments of the immiscible liquid can be aspirated between successive liquid segments, to maintain such liquid segments discrete.

Abstract: A method of transferring a substance adhering to the surface of a substrate to a receiving surface of a backing element which includes locating the substrate surface in juxtaposition with the receiving surface, supplying a transfer medium on the receiving surface in sufficient quantity to encapsulate the substance, joining the transfer medium on the backing element with a substance so as to encapsulate the substance within the transfer medium and removing the substrate to expose the encapsulated substance.

Abstract: Apparatus and method for permanently and protectively mounting "wet" thin sections of biological specimens on microscope slides, wherein each specimen is initially bathed in a low-volatile solvent containing a low concentration of first polymerizable material. Such solvent is allowed to evaporate, whereby the liquid polymerizable material permeates and protects the specimen. Following solvent evaporation, a second polymerizable material is layered over the specimen. Preferably, the first and second polymerizable materials comprise a mixture of low-volatility, low-viscosity, liquid acrylic reactomers and a U.V. light-sensitive catalyst system. A conventional cover slip or other planar transparent member can be positioned over the polymerizable materials, and the same are polymerized by exposure to U.V. radiation. The first and second now-polymerized materials encapsulate the specimen on the microscope slide, become integral and completely hardened and are fully devoid of any solvent.

Abstract: A liquid substance is transferred from a first carrier stream to a second carrier stream. The transfer includes the use of a movable conveyor and the flow of a deposited volume of the first stream along a portion of the conveyor as a sheath stream.

Abstract: Method and apparatus for the determination of the instantaneous flow velocity of a segmented fluid stream in an optically transparent conduit are disclosed, and comprise light-sensitive flow signal generation means operatively associated with said conduit and operable to generate a signal including a characteristic which is representative of said instantaneous flow velocity, and flow signal processing means which are operable to detect said characteristic and provide a signal indicative of said instantaneous flow velocity.

Abstract: Method and apparatus for casting a metal article in a mold at least as long as the article, utilizing a cooled mold of elongated form having top and bottom portions. The method includes the steps of introducing molten metal from a source through the bottom portion of the mold, flowing molten metal into the mold so as to form a solidifying casting shell which during casting occupies at least 40% of the cross-sectional mold area and has a molten core, and flowing molten metal from the source through the core towards the mold top.

Abstract: A method for determining a volume of red cells in a blood sample. The method includes the steps of flowing along a conduit a predetermined volume of the sample, introducing an agglutinating reagent and a predetermined volume of a dye into the conduit to mix with the sample and agglutinate the red cells, the dye being of known concentration on the introduction thereof, decanting the agglutinated red cells from the conduit, and colorimetrically measuring the concentration of the dye in the conduit, the agglutinating reagent being characterized by a relatively high positive electrical charge and the dye being water soluble and characterized by not penetrating said cells and not forming a precipitate with the agglutinating reagent or with the soluble components of the sample and not lysing the cells or altering the volume of the cells.

Abstract: A method, for microcoulometric determination either of the activity of an enzyme in a liquid sample or the concentration of a substrate for a reaction involving a change in a coenzyme from a first form thereof to a second form. At intervals during the reaction, both coenzyme forms are measured essentially simultaneously utilizing an electrolytic cell, to indicate either such enzyme activity or substrate concentration, depending upon which is the unknown factor.

Abstract: A multichamber cuvette for maintaining in independent and separate condition at least two reactants until such time that it is desired to mix them for reaction with each other and a reactant liquid sample for analysis in the cuvette. There is provided a cuvette body of a suitable plastic defining at least two chambers interconnected by a passageway of relatively small cross section having at least the end portions thereof of capillary size to prevent under many circumstances, as by surface tension, accidental mixture of liquid reactants in the chambers. If there is a substantial head of liquid in one chamber and/or a risk of impact of the cuvette with an external foreign object, sufficient to break such surface tension, an air lock in the passageway when the latter is below the liquid levels in the chambers prevents such accidental mixture. A baffle in the passageway enhances separation of liquids and/or solid substances in the chambers.

Abstract: Method and apparatus for improved optical discrimination in a total particle population of particles having a significant light absorption characteristic and particles having a significant light scattering characteristic. There is provided in such a method a combination of steps including, directing a beam of light from a source to transversely illuminate at an optical interaction station particles passed one by one through such station, partially obstructing the beam beyond the station for passage of scattered and unscattered portions of the beam, when a particle is in said beam and detecting one of said beam portions.

Abstract: A sampler is provided having a liquid sampling probe. A drive mechanism for the probe includes a screw element and a nut element threaded thereon, one of which elements is axially fixed and driven to axially raise and lower the other element which supports the probe. In one axial position of the element supporting the probe, the last-mentioned element is moved between first and second angular positions thereof.

Abstract: Method and apparatus are provided for the determination of the Raylographic information of a body part which is ensonified by acoustical energy pulses by a particularly precisely focused acoustical focusing system to produce acoustical energy echo pulses which are detected in coherent manner. Fourier transformation of the pulses from the time to the frequency domain enables frequency domain deconvolution to provide the impulse response with minimization of mathematical instabilities and distortion of the frequency domain impulse response. Noise extraction and spatial deconvolution filtering are included to respectively maximize signal to noise ratio and minimize distortive effects of body part surface non-orthogonality and combine with the above to provide for particular stability in the overall results and attendant increase in the axial resolution of Raylographic display and in the overall resolution of body part image displays.

Abstract: A method for analyzing a biological fluid sample for Ab, Ag, or Ab:Ag complexes therein which includes the step of adding to the sample a solution of RF or Clq to bind with Ab:Ag complexes present or formed therein, and thereafter analyzing the mixture so formed for complexes bound to RF.

Abstract: Apparatus and method for obtaining a concentration gradient in a liquid sample analyzer including flowing a first liquid in a stream to fill a conduit, and continuing the flow of the first liquid along the conduit subsequent to the filling step. Combined with these steps is the step of changing the concentration of the first liquid by removing from the stream a predetermined varying volume of the first liquid and adding to the stream a predetermined proportional varying volume of a second liquid. There is also provided a method of serial dilutions of a liquid stream in a conduit by removal of a portion of the stream prior to each diluent addition for the purpose of conserving diluents which may be reagents.