Abstract: Apparatus (FIG. 1), for training in the rapid and accurate reaction to a situation confronting one or more trainees 12, 12' in an enclosed room 11, has one wall thereof formed by a screen portion 14 onto which an optical image is back-projected by projector 16. Each trainee's weapon 22 has a light emitter 24 responsive to firing the gun (containing blanks) at the screen to simulate the projectile impact point by spot 26. A television camera adjacent the projector and viewing the rear of the screen receives the spot and relates the position of this within the camera field to datum points of the projected image, the datum points 36' being visible to the camera and not the trainee.

Abstract: A therapeutic material is contained in a water soluble glass having a dissolution rate that is distinctly pH sensitive, the ratio of dissolution rates between pH 2 and pH 6 being greater than 60 to 1. The glass incorporates phosphorus pentoxide as the glass former and an alkali metal oxide and one or more alkaline earth metal oxides as glass modifiers.

Abstract: Power supply apparatus for a gas laser discharge tube (10) having anode and cathode electrodes (11 and 12) comprises a first power supply (13) operable to satisfy the running power requirements of the discharge tube. A second power supply (16) is also provided and is operable to generate a voltage which, when connected in series with the output of the first power supply (13) causes the initiation of a discharge in the discharge tube (10). A spark gap (17) is operable to connect the outputs of the two power supplies in series with one another when the discharge is to be initiated.

Abstract: A middle ear prosthesis is constructed of a bio-active bio-compatible glass. The prosthesis includes a substantially disc-like base member, one base surface of which is adapted to bond to the tympanic membrane, and a substantially cylindrical stem member projecting from the other base surface. The axis of the stem member is offset from the center of the base member and perpendicular to the base surface.

Abstract: An optical reflectometer in which the output from a laser 11 is passed through a ramped phase modulator 12 and an optical fibre bi-directional coupler 13 to a transmission path 15, e.g. an optical fibre. Part of the light is coupled out to a mirror 14 and is reflected to form a local oscillator signal which is mixed in the coupler with backscattered light from the fibre. The mixed signals are applied to a detector 16.

Abstract: Novel hydrophilic protein or polypeptide microspheres prepared by dispersing an aqueous solution or dispersion of protein or polypeptide in an organic solvent solution of a high molecular weight polymer to form a stabilized dispersion of microspheres and cross-linking said microspheres with a polyfunctional cross-linking agent.

Abstract: The invention relates to transdermal drug patches for the controlled release of drugs to the human skin, comprising(a) an impermeable backing or covering layer,(b) a reservoir layer adjacent to, and in close contact with said backing or covering layer, said reservoir layer comprising a polymer matrix composed of a rubber and an adhesive resin material wherein said therapeutically active agent or agents are wholly or partially soluble and which is permeable to said agent or agents,(c) an adhesive layer adjacent to, and in close contact with, said reservoir layer and permeable to said therapeutically active agent or agents, and(d) a protective layer covering and adhearing to said adhesive layer and removeable therefrom for the use of said transdermal drug patch,the improvement wherein said drug or drugs in the rubber and adhesive resin material of the reservoir layer are present together with a polymer capable of swelling in water and insoluble in the rubber and adhesive resin material of the reservoir layer, t

Abstract: Serial safety bearing assembly includes two concentric bearing sets and an actuatable device for selectively switching to engage either the inner or the outer of the two concentric bearing sets upon failure of one set or to alternate to first one set and then the other set thus to prolong the working life of the two concentric bearings.

Abstract: An analgesia composition comprising an aqueous solution of a neurologically active agent in a concentration of from about 10.sup.-3 to about 10.sup.-13 grams/ml and a method of relieving pain comprising topically applying the composition to the genitalia of a human or non-human animal.

Abstract: The strength members of the optical fibre cables to be jointed comprise inner and outer layers of high-tensile wires (9, 10; 9', 10') arranged on respective pressure-resistant tubes (5; 5'), each containing an optical fibre package (not shown). The strength members are jointed by trapping the wires between a quill (15) and a ferrule (16) pressed towards the quill. The quill (15) is of a relatively hard steel and serves to partially reinstate the pressure tube between the ends of the cables, whereas the ferrule (16) is of a relatively soft steel. For jointing of two dielectric covered elements the ferrule is subsequently encapsulated in a dielectric moulding (27). A thin-walled reinstatement tube (17) is arranged between the quill (15) and one tube (5'). The cavity in the reinstatement tube (17) is larger in diameter than the cavity in the tubes (5 and 5').

Abstract: Surgical apparatus for use in contouring medical implants comprises a transparent enclosure adapted to be located on a metallic work surface in an operating theater, the enclosure being sized to enable manipulation of an implant therein by a surgeon for contouring, a stand connected to the enclosure for adjustably positioning and fixing a surgical drill in a preselected orientation with respect to the work surface such that the drill bit projects throughout an opening into the interior of the enclosure, the stand carrying a magnetic mechanism so as to enable the stand to be immobilized with respect to the work surface, and a movable cutting block having a disposable cutting surface thereon. The stand is connected to the enclosure by a metal tongue, slidably carried by the stand, which is received within a slot on the underside of the enclosure, and the cutting block is formed with a magnetic mechanism so as to enable immobilization of the cutting block with respect to the tongue.

Abstract: Improvements to guide tubes for the fuel assemblies of light water nuclear reactors, said assemblies being immersed in operation in the cooling water of the core of such a reactor, the guide tubes being of the type made from zircaloy and fixed at their two ends respectively to an upper end part and a lower end part made from stainless steel or Irconel and which incorporate devices for braking the fall of the control rods which they house during the rapid shutdown of the reactor, wherein the said braking devices are constituted by means for restricting the diameter of the guide tubes comprising for each guide tube a zircaloy inner sleeve spot welded to the said guide tube and whose internal diameter permits the passage, with a calibrated clearance, of the corresponding control rod, the sleeve being distributed over the lower portion of each guide tube and associated with orifices made in the actual guide tubes to produce the progressive hydraulic absorption of the end of the fall of the control rods.

Abstract: Optical four wave mixing is provided by interfering two waves on a liquid crystal layer (1) temperature stabilized just beneath its nematic/isotropic phase change transition temperature. The liquid crystal incorporates a guest dye to absorb the light producing a holographic thermal image which is accompanied by a holographic phase image. Illumination of this phase image with a `third wave` of different wavelength is then used to produce the required holographically diffracted `fourth wave`.

Abstract: Low concentration standard aqueous solution for analytical purposes is prepared from a water soluble glass body containing the standardizing material. The glasses are phosphorus pentoxide based glasses and provide release rates, e.g. of Na.sup.++, of 0.01 to 100 micrograms per cm.sup.2 per hour.

Abstract: A brace for treatment of distal radius fractures allows an adjustable range of motion while simultaneously providing for distal traction. The brace has hinges with adjustable stops, the hinges being made of radiolucent material to allow x-rays without the necessity of removing the brace. Adjustable tensioners are used to provide distal traction by way of a metacarpal pin placed in slots in hand members. The brace is adjustable for different size patients.

Abstract: Device for locking a cowl with double security, comprising panel securing means, constituted by a plate integral with the panel and having a conical hole, as well as by a conical stop integral with the fixed structure and which enters the plate hole when the panel is in the closed position. Locking means are constituted by a locking bush or flange integral with the fixed structure, a support mounted on the panel, a bolt mounted in pivotable manner on the support and able to engage in the locking bush when the panel is in the closed position. Elastic means draw the bolt towards the disengaged position of the locking bush. A pawl mounted on the support locks the bolt in the engaged position.

Abstract: Gas laser apparatus comprises a cavity 10 containing a gaseous active medium, and discharge electrodes 11 and 12 between which a potential difference may be applied to produce an electric pumping discharge in the active medium. A reservoir 17 communicates with the cavity to form a sealed enclosure containing the active medium and volume control means 19 are contained in the reservoir 17 to vary the pressure of the gaseous active medium in the cavity.

Abstract: Dynamic random element stereograms are produced on a television receiver or video monitor by an interface circuit that generates first and second binary sequences which are applied to the display so as to display a plurality of pairs of elements, and relative delays are introduced between the two binary sequences during selected portions of an image defined by a video signal so that the disparity between elements of those pairs displayed during the selected portions is different from the disparity between elements displayed during non-selected portions, thereby causing the selected portions to appear to be at a different depth from the non-selected portions.

Abstract: A dielectric composition comprising a ternary system of non-stoichiometric lead magnesium niobate, non-stoichiometric lead zinc niobate and non-stoichiometric lead iron niobate up to 10 wt % PbO may be added to the ternary mix. Compositions with firing temperatures in the range 950.degree. to 1040.degree. C., have dielectric constants in the range 13,900-22,100 making the composition particularly suitable for high silver content multilayer ceramic capacitors.

Abstract: A variable-temperature pressure coating system for optical fibres, particularly for uv-curable primary coatings, includes a gas cylinder (8) for pressurizing a tank (1) of coating material, and a heat exchanger (15) controlling the temperature and thus the viscosity of the coating material supplied to a die chamber (19) through which an optical fibre (18) is passed following drawing. The temperature of the die chamber may also be controlled by the same circuit as the heat exchanger. A valve (14) serves to control flow to the die and to enable priming of the tube (13) by filling with coating material (and removal of air bubbles) prior to supply thereof to the die chamber (19). The system is designed for ease of operator handling together with production of high quality coatings at high speed.