Abstract: A device for the sustained release of active substance comprises a wall defining a cavity for the reception of active substance, the wall being of impermeable material and having one or more ports therethrough. Sections of hydrogel material are within the cavity, the hydrogel, in use, being swollen to cover the ports in the cavity wall. Active ingredient is released from the container only through the hydrogel covering the ports. In this way sustained and controlled release of the active substance from the device is obtained.

Abstract: This invention relates to several thromboxane A.sub.2 inhibiting 7-[3-.alpha.-[1-[[(phenylamino)-thioxomethyl]hydrazono]ethyl]-bicyclo[2.2. 1]-heptenoic acids, pharmaceutical compositions employing them and methods of their use.

Abstract: A spray apparatus for the treatment of a harvested crop, the apparatus including a high voltage electrostatic spray head, a sprayhood surrounding the sprayhead and having an aperture opposite the sprayhead and insulating means to suspend the sprayhood with the aperture adjacent a region of a conveying path to establish and maintain the sprayhood covering said region of said conveying path, the sprayhood having on the outside an insulating cover and inside the cover an extensive insulated electrode extending around and above said aperture, the electrode being energizable in operation to a potential similar to that applied to the sprayhead, whereby the support means and electrode together permit the application of an electrostatically charged spray from the sprayhead in a controlled manner throughout said region of the conveying path under the sprayhood to a quantity of crop conveyed past on the conveying path in a regular manner.

Abstract: A method of manufacture of thin film, field-effect transistors formed on a transparent substrate and with transparent, conductive source and drain electrodes, uses initially deposited gate electrodes as a mask in association with photolithographic processing using radiation transmitted through the substrate and electrodes to minimize parasitic capacitance between the gate and source and drain electrodes.

Abstract: A device for administering oral fluid to a patient from a container (18) has a nipple (14) connected to the container (18) by a tube (16). The nipple (14) is held on the patient's tongue. A valve (22) opens in response to the patient sucking or pressing the nipple to initiate a flow of fluid in the tube (16). A detector (92) responds to this flow and switches on a peristaltic pump (90) for a period determined by the setting of a controller (102) to deliver positively a suitable bolus of 2 to 6 ml to the patient. To give the patient time to swallow the bolus, the detector (92) is inhibited for a predetermined delay period after termination of the bolus and over the same delay period, the tube (16) remains pinched or clamped.

Abstract: To separate minerals, they are made up into a slurry A applied to a hollow tapered cylinder 301 spinning on its axis to generate 10 g centrifugal force.The cylinder 301 is also subjected to axial vibration at 5 to 10 Hz. The cylinder widens at a half-angle of 1.degree., and its axis is inclined at 2.degree. upwardly in the direction of widening.A film of slurry is held centrifugally to the internal surface of the cylinder and kept in suspension by the vibration. The denser (i.e. higher specific gravity) particles in the slurry tend to move preferentially radially outwardly (centrifugally) and to move downwardly in the boundary layer (under Earth's gravity). The action of the washing water B is to displace waste accidentally entrained with the higher-specific-gravity-particles.The valuable higher-specific-gravity particles overflow downwardly continuously at C and are collected.

Abstract: Where a signature is to be automatically verified, or data is to be entered into a computer, a special pen is usually employed but this pen is liable to be stolen or vandalized. In the present invention the tip of an ordinary pen presses lined paper on to a transparent plate and modifies internal reflection in the plate at the point of contact. A light source edge-illuminates the plate and light received by a receiver at another edge of the plate varies in intensity as the pen tip crosses the lines. By measuring the intervals between crossing line boundaries information is obtained which can be analyzed for use in signature verification and data entry.

Abstract: In computer control of machine tools there is a need to measure the diameters of cylindrical workpieces automatically and preferably without touching the workpiece. For this purpose an inductive proximity sensor is mounted for circular or linear movement along a path adjacent to a cylindrical workpiece and in a plane normal to a radius of the workpiece. A discrete fast Fourier transform (FFT) is carried out on the output of the sensor as it moves along the path and the amplitude of the second ac component of the FFT is an indication of the workpiece diameter. By calibrating with workpieces of different diameters, the said amplitude can be used as a measure of workpiece diameter.

Abstract: An automatic chemistry machine particularly suitable for the automatic sequencing of DNA on the microliter scale including a source of reagents, a common means to transfer by contact microliter quantities of reagent, below 5 microliters, and a rotatable reaction surface to which said quantities of reagent are transferable, means to control the transfer means to access and contact specific spaced areas of the reaction surface, and means to control the rotation of the surface with regard to the transfer means action, the surface being formed to constrain flow of transferred reagent quantities over the surface and in a reaction area to mix under centrifugal action on faster rotation of the surface.

Abstract: An injection device which is devised to be safer in use than many prior such devices comprises a generally cylindrical barrel section which is substantially closed at its first end but has an aperture in that end to allow an injection needle to pass through it, a needle support member to slide within the barrel section and shaped to receive one end of a liquid container such as an ampoule of anaesthetic, and a plunger mounted at the other end of the barrel section for axial movement in said section. The plunger is adapted both to express liquid from the liquid container when the plunger is advanced within the barrel and also to interconnect with either the needle support member or the liquid container, whereby withdrawal of the plunger withdraws both the liquid container and also the needle and its support member into the barrel section for disposal.

Abstract: A pulse oximeter apparatus characterized in that it comprises a bandpass filter adapted selectively to exclude motion artefact from wanted signal is disclosed.Also disclosed is the use of such an apparatus for the determination of pulse rate and/or arterial blood oxygen saturation.

Abstract: An H-plane waveguide `T` junction is described in which matching is achieved over a full waveguide band at the waveguide which forms the stem of the `T`. Reflection from the wall facing the stem is reduced by using a probe as a monopole located about a quarter of a wavelength from the said wall. Variations with frequency in the reflection coefficient at the stem are reduced by a disc, at the foot of the probe, which acts as a radial reduced quarter wave transformer.

Abstract: Apparatus for monitoring fetal health during labor detects the occurrence of a fetal ECG in digital signals derived from electrodes on a fetus using a matched filter routine to detect a QRS complex. The peaks of successive R waves are then found and used to determine fetal heart rate. After time coherent filtering of digital samples representing the fetal ECG the P-R interval and the elevation of the S-T interval are found and a correlation coefficient between the fetal heart rate and the P-R interval is derived. The elevation and the coefficient are displayed. If the correlation coefficient becomes positive for about half an hour and a significant fall in the elevation of the S-T interval also occurs it is an indication of acidosis of the fetus.

Abstract: An apparatus for harvesting crop including a rotor (11) mounted on a movable frame (12) and carrying a succession of transverse combs (14) each formed of an array of outwardly projecting teeth (15) traverse to the direction of movement of the apparatus through the crop. Each tooth (15) is pointed with side edges diverging away from the distal tip of the tooth. The rotor rotates in the overshot mode and the combs intrude into the crop and gather crop stems between adjacent pairs of teeth and detach grain and grain heads, or other required crop parts, by rubbing or breaking the parts free from the stems. The junction of adjacent teeth (15) preferably has an enlarged aperture (21) to assist striping and to allow withdrawal of striped stems. In other embodiments, the teeth may be replaced by a brush-like structure or by rods or other crop engaging elements, backed by plain transverse ribs for collecting and conveying detached crop parts.

Abstract: A sensor for sensing magnetic fields. A single mode optical fiber has a core which is wound into a helical shape. The fiber is formed with a former and a core, and the core is preferably attached to the inner surface of the former and wound into a helical shape tracing its inner periphery. The core is also offset from the central axis of the fiber former.

Abstract: In transparent tone-in-band communication systems a notch in the frequency band is usually formed and then the resulting spectrum is translated in frequency to an intermediate frequency range as part of the transmission process. In a transmitter of the present invention a more simple arrangement is used in which the notch is formed directly in an intermediate frequency range by using mirror filters to divide an input signal into two portions and supply respective mixers, each having one output sideband in the intermediate frequency range. The mixers receive different reference frequencies and the mixer outputs are supplied to a summing circuit whose output is passed to a band pass filter to remove the unwanted sidebands. The original frequency spectrum is restored at the receiver by mixer processes of shifting the two selected sidebands similar to, but the inverse of, those used in the transmitter.

Abstract: An input signal passes by way of a variable gain amplifier to an output terminal. In addition the input signal is applied to a peak detector and then a control signal is derived by applying a smoothing function taking into account a predetermined number of peak values. A selected gain function is applied to the control signal. The control signal is preferably also multiplied by a compression control signal which acts on individual half cycles to bring all peak values in the output signal to the same value.

Abstract: Simultaneous time-variable and position-variable control of the polarization properties from any position along the length of an optical fibre, is effected by launching an acoustic disturbance into the fibre, thereby locally modifying the birefringence of the fibre. A current measurement device incorporating a monomode optical fiber 1 may be made insensitive to vibration by launching an acoustic wave from one end of the fiber. This wave 7 consists of two linearly polarized shear waves orthogonal in direction, and in phase quadrature is of such an amplitude and frequency as to provide a circular birefringence very much greater than the vibrationally-induced linear birefringence.

Abstract: Prostaglandin analogues exhibiting activity at thromboxane receptor sites have been prepared.

Abstract: This invention relates to several novel intermediates useful in the manufacture of thromboxane A.sub.2 inhibiting 7-[3-.alpha.-[1-[[(phenylamino)-thioxomethyl]hydrazono]ethyl]-bicyclo[2.2. 1]-heptenoic acids.