Abstract: A hip prosthesis has a shaft which is implantable in the femur, a ball head anchored on the shaft, a socket in which the ball head is movably supported, and a bipolar shell placed between the ball head and the socket, whereby the ball head rotates in the bipolar shell and the bipolar shell rotates in the socket.

Abstract: A display system, method for assembling a display system, and method for vending a display system are provided. The display system has a display, a write-once solid-state memory with image content stored in the write-once memory, and a display controller adapted to read the write-once memory and to cause the display to present the image content.

Abstract: The invention relates to a hip prosthesis having a shaft (1) which is implantable in the femur, and having a ball head (2) anchored on the shaft (1) by a conical clamp, for example, and having a socket (5) in which the ball head (2) is movably supported.

Abstract: A mechanism is described for attaching a fin to a projectile and for deploying the fin from a stowed position to a deployed position. In the stowed position the fin is parallel to a centrally located axis which extends from the front portion to the rear portion of the projectile. A mounting which is disposed in a bearing and to which the fin is attached permits pivoting of the fin and deployment of the fin in two phases. During the first phase the fin moves from the stowed position to a semideployed positions by rotation in the bearing about an axis normal to the projectile's centrally located axis. During the second phase the fin moves from the semideployed position to the deployed position by pivoting relative to the mounting.

Abstract: Thermostable, infusible and insoluble polymer obtained by thermosetting aromatic oligomers of low molecular weight in the presence of an acid catalyst, said aromatic oligomers having an average molecular weight up to about 5000, a softening temperature from 80.degree. to 400.degree. C. and being obtained by separation from the reaction mixture produced by reacting meta-terphenyl with acetyl chloride and aluminum chloride.

Abstract: New aromatic compounds with ether functions particularly useful as power transmission fluids and as lubricants withstanding high temperatures, containing at least a major proportion of a compound of the formula: ##STR1## WHEREIN EACH Ar is selected from phenyl and metaphenoxy phenyl and optionally a minor proportion of at least one compound selected from those complying with the general formulas: ##STR2## WHEREIN Ar is defined as above.