Abstract: A Class B push-pull amplifier designed for use at low supply voltages (e.g. 1 to 2 volts) wherein complementary push-pull output transistors T.sub.3, T.sub.4 are biased by a biasing chain consisting of resistor R.sub.1, transistor T.sub.1, resistor R.sub.2, transistor T.sub.2, resistor R.sub.3, with the signal to the bases of T.sub.3, T.sub.4 being supplied from opposite ends of R.sub.2. The value of R.sub.2 is twice that of R.sub.1 and R.sub.3. The circuit is preferably used in a bridge configuration with a second similar amplifier set at unity gain driven from the first amplifier. It may be used to power the loudspeaker of a miniature radio receiver.

Abstract: Radiolabeled angiotensin converting enzyme inhibitors having the general formula: ##STR1## wherein X is a radiolabeling substituent, preferably a radiolabeling halogen substituent such as .sup.123 I, .sup.125 I, .sup.131 I, .sup.75 Br or .sup.77 Br,Y is hydroxy, alkoxy containing from 1 to 6 carbon atoms, phenoxy, benzyloxy, or amino,R.sub.1 is hydrogen or methyl,R.sub.2 is hydrogen, an ester moiety hydrolyzable under mammalian in vivo conditions, such as alkyl of 1 or 2 carbon atoms, phenyl or benzyl, or an ionically bonded anion of a physiologically acceptable non-toxic salt, andm is an integer of from 1 to 6, are useful as in vivo radioimaging compounds for mammalian sites.

Abstract: An apparatus for preparing a sample of liquid for examination and analysis. The apparatus includes a tube closed at one end and open at the other, and a pipette dimensioned for insertion into the tube. The pipette has a sealing surface which is slightly smaller in diameter than the inside diameter of the tube. Protruding from the sealing surface is a rib which is aligned along the longitudinal axes of the pipette and which engages a portion of the inside wall of the tube to maintain the pipette in the tube.

Abstract: An amplifier for use in the I.F. stages of an F.M. radio receiver comprises several identical direct-coupled stages 2,4,6 each comprising common emitter transistors 8 and inductive loads 10.

Abstract: Preparations useful in the diagnosis of infectious mononucleosis are disclosed. Horse and sheep erythrocytes are purified and essentially homogenous glycoproteins are extracted. The purified glycoproteins are useful as antigens in testing for the presence of the heterophile antibodies of infectious mononucleosis and in the preparation of reagents for the enumeration of rosetting lymphocytes without having to have available fresh sheep blood.

Abstract: A filling station for filling flexible containers with liquid. The filling head is fixed. The container is gripped and brought into abutment with the filling head outlet. The container is filled and subsequently while the container is still in abutment with the filling head it is heat sealed. The container is then removed.

Abstract: A games table comprising a first games playing surface and a second table top surface normally disposed above the games playing surface, the second table top surface being formed by two panel elements or two groups of panel elements connected to the games playing surface whereby the panel elements can be moved bodily and pivoted to a non-vertical position adjacent to and substantially below the level of the games playing surface, and an elevating mechanism being provided to enable the games playing surface to be moved to a level suitable for use as a games table.