Abstract: A mould for cast moulding a contact lens comprises a first cup member having a male mould surface and a second cup member with a female mould surface. The two cup members form a piston and cylinder and are used in a pressure vessel so as to apply loading pressure to deflect the mould surfaces to maintain the surfaces in contact with a lens being cast. The mould is opened with the mould surface facing upwardly. Hydrating fluid is added to the first cup member and a cover sealed to the top of the first cup member.

Abstract: A method for determining motility comprising the detection, by means such as a transducer, of vibration of the external abdominal surface generated by gastrointestinal vibration and analysis of the signals produced by the transducer. Means are provided for integrating the signal over discrete time intervals in order to obtain meaningful results.

Abstract: Dental cement comprising (a) calcium or zinc oxide or hydroxide, (b) a substituted aromatic compound capable of forming a cement with (a), the calcium or zinc oxide or hydroxide of (a) being in stoichiometric excess over (b), and (c) dry poly(carboxylic acid), or a precursor thereof, or dry cation-crosslinkable polymeric acid containing on average 1 phosphonic acid group per 1 to 3 backbone carbon atoms. The cement has bacteriostatic properties, stimulates the formation of secondary dentine, forms an adhesive bond and can be used where pulp tissue is exposed.

Abstract: A spray head including a flow passage for the liquid to be sprayed and a rotary distributor head interrupting the forward flow of liquid from the flow passage. The distributor head presents the liquid flow with an imperforate redistribution surface which inclines obliquely across the flow so as in operation to redirect the flow both forwardly and rearwardly of the distributor head. In one version of the device, the distributor is provided with angled impeller surfaces so as to derive a distributor-rotating reaction force from the flow of liquid received from the flow passage.

Abstract: A pillow is of rectangular form and formed by adhering together a top part and base part, the top part being of a softer material than that of the base part. The base part has front and rear rolls at its longer sides and side rolls at its shorter sides, upper and lower surfaces of the pillow having respective large, central recessed areas between the front and rear rolls, the rolls being interrupted by minor recesses extending from respective sides of the pillow into the central recessed areas of the upper and lower surfaces respectively, the front and rear rolls forming on each surface a central main buttress and together with the side rolls forming four corner buttresses, side buttresses also being formed between pairs of adjacent corner buttresses respectively, the side buttresses tapering in width and height away from their respective associated sides of the pillow into a central recessed area.

Abstract: A heterodyne interferometer to achieve simultaneous and independent measurements of amplitude and phase includes a beam splitting device, BS which splits of the incident light beam into two parts with equal amplitudes and an angular deviation, .alpha.; imposes two unequal frequency shifts F.sub.1 and F.sub.2 on the two beams and amplitude modulates the two beams in phase quadrature at frequency F.sub.s. The two beams emerging from the beam splitter BS are focused by a lens L1 normally on to the surface of an object O. Upon reflection from the object surface, the two beams traverse through the lens and beam splitter a second time, where they are recombined. Both the frequencies and the amplitudes of the two beams will be shifted (or modulated) again after the second passage. The recombined beam is then diverted towards a photodetector PD via the beamsplitter.

Abstract: In deriving a control signal for recombining the parts of the spectrum separated by a frequency notch in transparent tone-in-band signals, cross-correlation products give rise to undesirable frequency and phase jitter. In a receiver which overcomes this problem an input signal E containing the notch is passed to two first mixers and then portions corresponding to the lower and upper portions of the input spectrum are selected by two mirror filters before being translated in frequency by two second mixers to a final output band in which the notch is eliminated. Two selection filters select parts of the spectra at the outputs of the first mixers which correspond to an overlap region of the said lower and upper portions when derived in a transmitter and apply them to a control-signal mixer. A control signal for the second mixers is derived from the output of the control-signal mixer by noise filtering and frequency division by two.

Abstract: In a method and apparatus for formation of an extruded product from material containing fibrous, molecules or other constituents succeptable to alignment, while the extrudate is still molten and moving through the die (5), in the direction of the extrusion axis (11), it is subjected to pulsating displacements in a direction transverse relative to that axis. These displacements give rise to a shearing action within the material, resulting in a degree of transverse orientation of the constituents. This orientation may be "locked in" to the extruded product when the melt solidifies (40), so improving the transverse strength of that product, and/or may correct an unwanted orientation (from 112, FIG. 16) that existed in the melt upstream of the point where the pulsating displacements were applied. The displacements may be applied by the synchronized operation of pistons (20-27), operating in chambers (17) which open into the die cavity (18) at separated locations all lying in the same transverse plane.

Abstract: An exothermic chemical process carried out above atmospheric pressure, in which a first pressurized gas stream from the process and a second pressurized fluid stream containing an excess of high temperature heat from the process is passed through a heat exchanger to heat the first pressurized gas with a portion of the excess high temperature heat, and the heated first pressurized gas is expanded to generate work. An additional amount of pressurized gas and at least a portion of the second pressurized fluid stream is passed through a heat exchanger to heat the additional amount of pressurized gas with another portion of the excess high temperature heat contained in the second pressurized fluid stream, with the additional amount of pressurized gas being independent to the amount required or produced by the process.

Abstract: Compounds of formula (I) ##STR1## in which R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each separately selected from hydrogen, X, NH--A--NHR and NH--A--N(O)R'R" wherein X is hydroxy, halogeno, amino, C.sub.1-4 alkoxy or C.sub.2-8 alkanoyloxy, A is a C.sub.2-4 alkylene group with a chain length between NH and NHR or N(O)R'R" of at least 2 carbon atoms and R, R' and R" are each separately selected from C.sub.1-4 alkyl groups and C.sub.2-4 hydroxyalkyl and C.sub.2-4 dihydroxyalkyl groups in which the carbon atom attached to the nitrogen atom does not carry a hydroxy group and no carbon atom is substituted by two hydroxy groups, or R' and R" together are a C.sub.2-6 alkylene group which with the nitrogen atom to which R" and R" are attached forms a heterocyclic group having 3 to 7 atoms in the ring, but with the proviso that at least one of R.sub.1 to R.sub.4 is a group NH--A--N(O)R'R", and physiologically acceptable salts thereof are of value in the treatment of cancer.

Abstract: A drive circuit including a power stage [PSH/PSV] and a control stage therefor to co-operate to supply energy in a controlled manner with regard to a reference value to an inductive load when connected in operation, means [R21, R41/R25, R42] in the power stage to produce a lower level signal indicative of the energization of the load, means [HPR/VPR] to generate a reference value for the energization signal representing a required energization, means [U3.3/U3.4] to compare the energization signal and the reference value and generate an error signal representing any difference therebetween and means [U2.1/U2.3, U2.4] to apply said error signal to said control stage to alter the energy supplied to the load towards the required condition, the reference value may also be related to the frequency at which the load is energized (SE, FBF, OSC, D4).

Abstract: A powered respirator of self-contained form for use in oxygen-sufficient atmospheres comprises a visored helmet (10) defining in use a passageway (15) extending from a rear opening (16) across the user's head (13) and face, an electric fan (17) and filter (19) located adjacent the opening to pass respiration air through the passageway, a fan battery (18) housed forwardly of the helmet, and an exhaust valve (20) mounted in the passageway near the user's mouth, the valve operating to open in response to gas pressure similar to that of normal exhalation and including a spring closure mechanism having a decreasing spring rate during opening.

Abstract: A transplanting apparatus for transplanting plants from free draining matrix trays in which each plant containing cell of each matrix tray is provided with a drainage hole at the bottom of a cell. The transplanting apparatus has a matrix tray rotary supply device, an expulsion/indexing device, a plant catching device, and a planter device. The matrix tray rotary supply device vertically holds and supplies matrix trays to the expulsion/indexing device, and rotates to supply a new matrix tray. The explusion/indexing device moves a supply matrix tray in a row by row movement and expulses one row of plants after the other. The plant catching device catches the expulsed plants and aligns the expulsed plants root end down, and the planter device plants the expulsed aligned plants.

Abstract: A method of analysis of a gaseous sample comprises the steps of introducing into a quistor a sample of ions characteristic of the gaseous sample, applying a potential to the electrodes of said quistor so that only one ionic species is stable in a trap of said quistor at any given instant, incrementing the potential applied to the electrodes of said quistor so that said ionic species becomes unstable and is ejected from said trap and determining the mass/charge ratio from the measurements of the parameters of said ion trap at the point of instability.

Abstract: Seed is primed by progressive hydration in a rotating drum (1) by water introduced as steam from a steam generator through an outlet pipe (5) to condense as a mist on the drum walls or as liquid water pumped onto the drum walls through several fine bore tubes to form a surface film. The amount of water and its rate of addition is controlled such that the seeds remain free flowing.

Abstract: The polymerization of a cationically polymerizable resin especially an epoxy resin is effected by placing it adjacent to but not in contact with a layer comprising a photoinitiator. The preferred initiators are salts which comprise a fluorine atom such as hexafluorophosphate and tetrafluoroborate salts. The initiator may be irradiated separately which facilitates the curing of resins containing pigments. The products are free from contamination by unreacted initiator.

Abstract: In a row crop harvester a rotor 11 has rows of crop engaging elements 15 extending transversely across the direction of forward travel of the machine, the elements being aligned with the rows to be harvested. Each element has inwardly coverging side edges for gathering the crop of a row and for detaching required crop parts which are impelled in a high-speed stream upwardly and rearwardly over the rotor beneath a hood 18. At the junction of each inwardly coverging pair of edges a space 21 is provided for stripping crop and releasing stripped stems. Preferably the space 21 is a relief space having re-entrant edges 20 for stripping forwardly facing parts of the crop.

Abstract: 3-Alkyl- or fluoroalkyl-3-(4-pyridyl)piperidine-2,6-diones, useful in the treatment of breast cancer, of formula ##STR1## wherein R represents an alkyl group having 2 to 10 carbon atoms or a fluoroalkyl group having 2 to 5 carbon atoms and A is hydrogen or an alkyl group having 1 to 4 carbon atoms, are prepared by reacting a 4-pyridylacetate with an alkyl or fluoroalkyl iodide, chloride or bromide, in the presence of a sterically bulky base and reacting the product with acrylamide in the presence of a sodium or potassium branched chain alkoxide. Preferably potassium t-butoxide is used in both stages and they are carried out sequentially at room temperature in an alcoholic or polar, aprotic solvent in a single reaction vessel.

Abstract: The invention relates to matching asymmetrical discontinuities in transmission lines to give low reflection coefficients (less than five percent) over a wide frequency band (corresponding to at least an octave in wavelength). A group of asymmetrical discontinuities, such as impedance steps in a waveguide, are matched by considering a reference plane whose position varies with frequency at which the reflection coefficient for waves transmitted in one direction is equal to that for waves transmitted in the opposite direction. Matching elements are then provided which have a reflection coefficient at the reference plane which is equal and opposite to the reflection coefficient of the discontinuities. Matching is less difficult if the distance between the steps is less than a quarter of a guide wavelength at all frequencies in the wide band mentioned above and such an arrangement is a "reduced quarter wave transformer".

Abstract: A communication system which uses a transmitter and a receiver. The transmitter divides a band of interest in the frequency spectrum into upper and lower portions, and frequency translates one of these portions in order to provide a frequency notch between the portions. The receiver of the system includes a receiver processor which receives the upper and lower portions, and which restores the original frequency spectrum. The receiver processor at least partially determines the final position of the restored portion.