Abstract: A method and apparatus for harvesting cells from a fluid so as to preserve the integrity of the cells when used in the diagnosis of cancer. The apparatus comprises a filter adapted to collect cells of a predetermined size, a fluid pathway arranged to transmit fluid to and from the filter, a pump which provide a positive pressure which urges the fluid to the filter along the fluid pathway and a negative pressure which draws the fluid from the filter along the fluid pathway and which operates to pass the sample through the filter in a first direction to collect cells on the filter. A second pump operates to pass a cell preservative fluid through the filter in a second direction to remove cells from the filter for collection. A controller is provided to regulate the flow of fluid along the fluid pathway. The method and apparatus provides a gentle pressure gradient which minimises damage to the cells during the process of filtration and collection.

Abstract: A digital switching system for establishing safety communications between N junctors is intended to guard against the potential danger of generalized failure which lies in the use of a central control unit and digital connection network for carrying out exchanges of information between junctors. Accordingly, each junctor is directly coupled to the N-1 other junctors of the system and is provided with its own control unit and its own digital connection network in order to enable said junctor itself to select the particular information which it is desired to receive from the N-1 other junctors. This system is primarily applicable to air and ocean traffic control.

Abstract: A fastening device is disclosed for joining two members, for example tubular members, together, one of the members having a recess in an end which is to abut the other member. The device includes wedge elements which are moved relative to one another to engage opposed internal walls of the recess in the one member so that by attaching one of the wedge elements to the other member the members are secured to one another. Deformable links interconnect the wedge elements to initially retain the elements in their operative positions but to subsequently deform when relative movement is produced between the elements.

Abstract: A fastening device is disclosed for joining two members, for example tubular members, together, one of the members having a recess in an end which is to abut the other member. The device includes wedge elements which are moved relative to one another to engage opposed internal walls of the recess in the one member so that by attaching one of the wedge elements to the other member the members are secured to one another. Deformable links interconnect the wedge elements to initially retain the elements in their operative positions but to subsequently deform when relative movement is produced between the elements.