Abstract: A fluid collection device is provided which includes a container for receiving a liquid, such as blood, which is centrifugally separable into relatively light and heavy phases, and a phase partitioning device in the container. The partitioning device includes a bag filled with a thixotropic gel-like sealant having a specific gravity between the specific gravities of the separated light and heavy phases. During centrifugation, the components of the cellular phase cause collapse of the bag and the flow of sealant through an outlet in the bag. The sealant flows to the interface between the two phases during centrifugation and provides a barrier between the separated phases.

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: A stopper for a blood collection tube adapted to receive whole blood for centrifugal separation into its relatively light and heavy phases. The stopper is provided with a coating which prevents red blood cells from adhering to it so as to avoid red cell contamination of the lighter phase after phase separation. The stopper is coated with a cationic binding agent, such as tridodecylmethylammonium chloride, and then with an anionic anticoagulant such as dextran sulfate. A lubricant, such as silicone oil, is applied to the coated stopper to facilitate insertion of the stopper into the tube.

Abstract: Apparatuses and methods for simultaneously extruding two lengths of plastic tubing wherein each of said lengths includes alternate axial sections of materials having different characteristics (e.g., a harder material and a softer material). The apparatus includes two extruders which feed plastic extrudate to a dual die head having first and second dies for forming tubular lengths. Valves are operatively associated with each extruder for selectively feeding plastic extrudate from each extruder to either of the dies. The valves are intermittently operated so that during one cycle extrudate from the first extruder is fed to the first die and extrudate from the second extruder is fed to the second die, and during alternate cycles extrudate from the first extruder is fed to the second die and extrudate from the second extruder is fed to the first die. A cooling tank receives the tubular length from the dies for setting the plastic material.

Abstract: A tracheostomy tube assembly (10) includes a tracheostomy tube (11) and a neck collar (14), which limits movement of the tracheostomy tube (11), but allows adjustment of the height of the tracheostomy tube (11). The collar (14) has a deformable sleeve (29) that is oversized relative to a portion of the tracheostomy tube (11) which extends therethrough. In an undeflected condition, portions (46,46) of the sleeve (29) engage the tracheostomy tube portions (43) to fix its height. When the sleeve (29) is deflected by compressing the sleeve (29) together at selected points, the engaging sleeve portions (46,46) will be deflected away from the tracheostomy tube portions (43) to permit axial movement thereof.