Abstract: Apparatus for electrical flash butt welding the ends of metal sheet or strip including a pair of flat faced parallel welding electrodes extending across the full width of the metal sheet or strip, one on each side thereof, and an electrode cleaning device comprising a support assembly having mounted thereon an extendable electrode cleaning means including a cleaning head having a plurality of upward extending cleaning members and a plurality of downwardly extending cleaning members the cleaning head adapted to simultaneously remove dirt and contaminants from the contact surfaces of opposed welding electrodes.

Abstract: A device for separating and isolating heavier components from lighter components of blood mixtures after centrifugal separation, comprising a barrel for holding the blood mixture having slidably positioned therein an inner container for containing the lighter components, a one-way valve responsive to movement of the container within the barrel (a) for controlling the flow of the lighter components into the container, (b) for preventing the lighter components from re-entering the barrel from the container, and (c) for creating a vacuum to assist in drawing the blood mixture to be separated into the barrel, and a filter for filtering the lighter components during their entry into the inner container. The inner container includes an opening for access to the separated and isolated lighter components.

Abstract: A biopsy device is provided that includes a housing and relatively slidable tissue cutting and stylet members, both movable with respect to the housing. The members have actuators for manually moving the members and which are mounted in parallel relation to each other and when the proximal ends are equidistant from the housing, the cutting member covers a tissue receiving cavity in the stylet. The actuators are provided with stops to prevent the distal tip of the cutting member from moving distally beyond the distal tip of the stylet. A hand grip can be releasably attached to the device.

Abstract: A lancet injector is provided which has a tubular housing, a slidable lancet holder in the housing, a compression spring connected between the holder and one end of the housing, and a holder control member extending through a longitudinal slot in the sidewall of the housing. The control member is operable to move the lancet holder to a latched retracted position against the force of the spring, release the holder so that it moves linearly under the force of the spring and inertia to a skin piercing position and then back to a neutral position in which the spring is in a free length condition.

Abstract: A lancet injector is provided which has a tubular housing, a slidable lancet holder in the housing, a compression spring connected between the holder and one end of the housing, and a holder control member extending through a longitudinal slot in the sidewall of the housing. The control member is operable to move the lancet holder to a latched retracted position against the force of the spring, release the holder so that it moves linearly under the force of the spring and inertia to a skin piercing position and then back to a neutral position in which the spring is in a free length condition.

Abstract: A blood collection device for collecting and separating whole blood into its relatively low and high density phases includes a collection container, and a housing having an enlongate passageway in the housing. Gel-like material having a specific gravity intermediate the specific gravities of the separated high and low density phases is disposed in the passageway. A piston having a specific gravity greater than that of the gel-like material is disposed in the passageway and sized to allow gel-like material to flow past it at a low flow rate and to retard the movement of the piston during centrifugation of the device. Means for preventing the flow of the gel-like material from the housing and toward the interface of the phases until the piston has moved out of the passageway is provided.

Abstract: A disposable tip and piston assembly for a pipettor mechanism includes a hollow tip member adapted to be detachably connected on the distal end of the pipettor mechanism, and a piston member slidably disposed within the tip. The pipettor mechanism includes a plunger rod adapted to detachably engage the piston, and an ejector mechanism which permits rapid removal of the tip and piston assembly without the user contacting the assembly. The piston member is adapted to directly contact the substance being pipetted, for high accuracy in pipetting. The ejector mechanism and the detachable connection of the tip and piston assembly to the pipettor mechanism insulates the pipettor mechanism and its operator from contamination by the substance being pipetted.

Abstract: An improved, four-chamber chest drainage system include (1) a collection chamber for collecting blood and other liquids to be drained from the pleural cavity of a patient, (2) an underwater seal chamber for preventing contamination of the patient's pleural cavity by atmospheric air, (3) a manometer chamber for accurately indicating the negative pressure in the patient's pleural cavity, and (4) a suction control chamber for regulating the amount of negative pressure (or suction) applied to the patient's pleural cavity. The suction control chamber has a flexible diaphragm adapted to flex in response to increased negativity above a predetermined level to block the opening to the suction source until the negativity returns to the predetermined level. A combination vent valve-and-filter assembly permits ready venting of the collection chamber to filtered atmospheric air.

Abstract: A blood collection tube is provided with a blood phase partitioning device disposed in the upper portion or adjacent the low density blood phase end of the tube. The device carries blood phase barrier gel-like material which flows through a restricted orifice in the device to meter or reduce the flow rate of the material into the blood during centrifugation to suitably delay the formation of the complete phase barrier until complete blood phase separation has taken place.

Abstract: A method of demodulating a pulse width modulation encoded analog signal wherein the analog signal is retrieved from individual pulse width modulation cycles. A method of sampling and outputing the retrieved analog signal only if missing pulse detectors confirm that the pulse width modulation cycle was valid. And a method generating a second but inverted play-back signal permitting use of two identical pulse width modulation transition descriminators-detectors.

Abstract: A fluid collection device is provided which includes a container for receiving a liquid, such as blood, that is centrifugally separable into relatively light and heavy phases, and a phase partitioning device in the container. The partitioning device includes a thixotropic gel-like material adjacent one end of the container having a specific gravity between the specific gravities of the light and heavy phases, and a piston member having an outlet in communication with the sealant so that during centrifugation of the device, centrifugal forces cause the piston to pressurize the sealant and force the sealant through the outlet toward the interface of the phases with sealant forming a partition between the separated phases.

Abstract: An economical, practical method of bringing the major portion of a classroom teaching experience to a remote student. The teacher's oral and blackboard presentations are recorded, forwarded to the student and played back on equipment that reproduces the teacher's voice and his or her graphics that would normally be presented on a blackboard, retaining the time correlation between the spoken and written texts.

Abstract: A fluid collection device for receiving a liquid, such as blood, and which is adapted to be centrifuged to separate it into its relatively light and heavy phases. The collection device has a phase partitioning device having a specific gravity intermediate those of the light and heavy phases of the blood so that it automatically moves during centrifugation to substantially the interface of the phases to sealingly partition them from each other. The device has a resilient sealing member which is of conical or "umbrella" configuration, and another member of different specific gravity connected to the sealing member and having stabilizing members for maintaining the sealing member properly oriented in the container. The sealing member partially collapses during centrifugation to allow blood components to pass by the sealing member.

Abstract: A blood collection tube useable with a needle holder for drawing blood from a body vessel. The tube has a rubber stopper with an annular axially extending portion in tight sealing engagement within the bore of the tube for maintaining a negative pressure in the tube. An annular groove in the annular portion of the stopper has a vacuum loss indicating member for providing a visual indication that the tube has or does not have a negative pressure therein. The vacuum loss indicating member may be cobalt chloride responsive to atmospheric moisture, a material including methylene blue that is sensitive to oxygen, or a closed-end manometer which has a quantity of liquid therein in a balanced position when normal negative pressure conditions exist in the tube and which moves within the manometer to visually indicate a loss of pressure when such occurs.

Abstract: A blood collection device includes a tube for receiving a sample of whole blood for centrifugal separation into the lighter phase, plasma or serum, and the heavier cellular phase. The tube has a needle-pierceable stopper at one end for maintaining a negative pressure in the tube. A blood phase partitioning device is disposed within the tube and includes an upper cylinder member and a lower piston member slidable in the upper member. The cylindrical member has a plurality of peripheral holes therein and a specific gravity greater than that of the piston member, with the members together having a specific gravity between that of the lighter phase and that of the heavier phase. A sealant is disposed within and in direct contact with the cylindrical member and has a specific gravity substantially equal to that of the two members together.