Abstract: Particles, useful as a delivery system for an epitope, are composed of a chimaeric hepadnavirus core antigen protein wherein a foreign amino acid sequence comprising an epitope is inserted in or replaces all or part of the sequence of amino acid residues from 68 to 90 in the case where the core antigen is hepatitis B core antigen or the corresponding amino acid sequence in the case of the core antigen of another hepadnavirus.

Abstract: A peptide and veterinarily acceptable salts thereof are disclosed which comprise an amino acid sequence which is derived from foot-and-mouth disease virus (FMDV). The peptide is independent within the FMDV structure of a B-cell epitode and is capable of eliciting T-cell help in an animal susceptible to FMDV infection for production of antibody against an antigen. Optionally, an amino acid in the sequence may be replaced by another amino acid which does not affect the function of the sequence to elicit T-cell help.

Abstract: According to this invention there is provided a ball and socket joint for use on automobiles and more particularly for use in the steering and suspension systems of automobiles. The ball joint includes a ball pin, the ball of which is rotatable within a housing and is capable of limited universal rotational movement therein. Such constant movement causes wear within the joint and it is desirable to have some means of readily assessing this wear.To enable this wear to be readily estimated by some means external to the housing, the bearing end cap is slidably engaged along one axis with a second member, substantially external to the housing and which is fixed relative to the housing along the one axis and also is rotatable about the said axis. The bearing end cap being displaced by a spring means from either of a rotatable or an interlocked state relative to the second member, to the other of the alternative states, such displacement be accommodated by the wear within the ball joint.

Abstract: The invention is concerned with a pivot joint having means for indicating wear thereof. The pivot joint comprises a headed pin, a socket in which the head is engaged and from which the pin projects, mating bearing surfaces on the head and the socket such that the pin is movable angularly with respect to the socket, a wear indicator extending through an aperture in the sockets and having its inner end engageable with the head, and a diaphragm which extends between the indicator and the socket to seal the bearing surfaces against ingress of foreign matter through the aperture.