Abstract: A method of partitioning a pre-selected phase of a sample of liquid having a plurality of phases of differing densities, a separating element and a tube containing the separating element. The sample of liquid is placed in a first chamber of a tube that is separated from a second chamber by a separating element. The separating element slidably engages the interior surface of the tube in a substantially fluid-tight manner. A fluid passage is disposed through the separating element and includes an initially closed fluid passage. The phases are ordered by axial centrifugation wherein the tube is rotated about its longitudinal axis, the separating element is moved within the tube reducing the volume of the first chamber, a pre-selected phase of the liquid is forced from the first chamber through the fluid passage into a second chamber. The reduction of the volume of the first chamber is controlled using phase-separation information. The separator may also include a filter for filtering the fluid.

Abstract: Apparatus for collecting, containing and separating a sample of blood. Disclosed is an apparatus for separating a pre-selected phase of a sample contained in an enclosed chamber, wherein said apparatus can be used with a separating means which rotates the chamber about a longitudinal axis of the chamber. In addition, separating means in which such an enclosed chamber is rotated about a longitudinal axis is described.

Abstract: Apparatus useful in surgery for holding retractors and other surgical instrumentation in a number of different positions required by a surgeon for the performance of a surgical procedure, including advanced sensing and regulation of retraction pressures and position; and incorporating a force amplification method to drive a locking mechanism in the supporting structure that utilizes a constrained, substantially incompressible, flexible solid material to yield a mechanism that is suitable for clinical use.

Abstract: Method and apparatus for partitioning a pre-selected phase of a sample of liquid, such as blood, having a plurality of phases of differing densities the method comprising the steps of introducing a sample into a chamber of constant cross-sectional shape and a volume greater than that of the sample, ordering the phases of the sample concentrically by rotating the chamber about its longitudinal axis, reducing the volume of the chamber in response to a separation control signal, removing a portion of the separated sample in order of phase, deriving information about the portion of the sample being removed from the chamber and modifying the separation control signal in response to the derived information.