Abstract: In speech recognition it is advantageous to take account of noise levels both in recognition and training. In both processes signals reaching a microphone are digitized and passed through a filter bank to be separated into frequency channels. In training, a noise estimator and a masker are used with a recognizer to prepare and store probability density functions (p.d.f.s) for each channel partially defining Markov models of words to be recognized. The p.d.f.s are derived only from input signals above noise levels but derivation is such that the whole of each p.d.f. is represented. In recognition, "distance" measurements on which recognition is based are derived for each channel. If the signal in a channel is above noise then the distance is determined, by the recognizer, from the negative logarithm of the p.d.f. but if a channel signal is below noise then the distance is determined from the negative logarithm of the cumulative distance of the p.d.f. to the noise level.

Abstract: A carbon block acts as a cell electrode. Channels are formed in its face which is to face the cell diaphragm. The channels provide an interconnected network including retention pools arranged to hold, release, break up and mix a liquid stream passing through them.

Abstract: Compounds having thromboxane antagonist activity are of use in the treatment of hormone-dependent neoplasias for example oestrogen-dependent neoplasias. Thromboxane antagonists of particular value are compounds of formula (I) ##STR1## wherein ##STR2## represents one of the divalent cyclic groups ##STR3## the letters a and b indicating in each case the points of attachment of the substituents R.sup.1 and CV(R.sup.2)--NV'R, respectively; R.sup.

Abstract: Compounds of the formula (II) ##STR1## wherein R.sub.1 and R.sub.2 are each separately selected from hydrogen, alkyl, alkenyl and alkynyl groups having up to a maximum of four carbon atoms and being unsubstituted, and alkyl, alkenyl and alkynyl groups having up to a maximum of three carbon atoms and being substituted by one, or in the case of fluoro by one or more, substitutents but with the proviso that when R.sub.1 is hydrogen then R.sub.2 is hydrogen or methyl, or R.sub.1 and R.sub.2 together constitute an ethylene bridging group, and R.sub.3 is a group which under physiological conditions undergoes elimination with the formation of a 3,5-dioxopiperazinyl ring, with the further proviso that the compound is in the meso or erythro configuration when each of R.sub.1 and R.sub.

Abstract: New C-substituted crown ethers such as ##STR1## are made by reacting a 1,2-diol (chain length m+4) with ClCH.sub.2 --(CH.sub.2 --O--CH.sub.2 --).sub.n+1 CH.sub.2 Cl.These compounds have a stronger affinity for secondary amines than for tertiary amines and therefore may be used to separate mixtures, especially when attached to polysiloxane backbones or substrates via their unsaturated bond.

Abstract: A rotor assembly for use in a poultry harvester, comprising first and second rotors arranged side by side about a center line of the assembly for rotation about vertical or predominantly vertical axes, a third rotor equispaced from the first and second rotors in a direction along the center line of the assembly, and drive means for rotating the third rotor in a clockwise or anticlockwise sense, as desired, during operation of the assembly, the drives for the first and second rotors being derived from the motion of the third rotor and being operative to counter-rotate the first and second rotors in rotational senses which remain unaltered irrespective of the direction of rotation of the third rotor at any given moment, each rotor providing a continuous array of radially-extending guide elements closely adjacent and/or abutting and/or intermeshing with the guide elements of the other rotors.

Abstract: An incontinence device which includes a garment having a sewn-in absorbent pad. A sheet of liquid impervious material is interposed between the garment and the surface of the absorbent pad remote from the wearer. The absorbent pad is coupled to the sheet of liquid-impervious material by stitching then the sheet is coupled to the garment by portions of the sheet turned back from the stitching of the pad to the sheet and stitched to the garment. In a further embodiment, a layer of permeable hydrophobic material is provided intermediate the pad and the wearer.

Abstract: A magnetic coil comprising a plurality of conductors is designed by calculation of the continuous current density required on the surface on which the conductors are positioned to generate a specific magnetic field on a further target surface or at specified points.

Abstract: Zinc(II) complexes in which at least one ligand is provided by a compound being:(1) 3-hydroxy-4-pyrone or a 3-hydroxy-4-pyrone in which one or more of the hydrogen atoms attached to ring carbon atoms are replaced by an aliphatic hydrocarbon group of 1 to 6 carbon atoms; or(2) a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic acyl group, by an aliphatic hydrocarbon group of 1 to 6 carbon atoms, or by an aliphatic hydrocarbon group substituted by one or, except in the case of ionizable groups, more than one substituent selected from aliphatic acyl, alkoxy, aliphatic amine, aliphatic amide, carboxy, aliphatic ester, halogen, hydroxy and sulpho groups and, optionally, in which one or more of the hydrogen atoms attached to ring carbon atoms are replaced by one of said substituents, by an aliphatic hydrocarbon group of 1 to 6 carbon atoms, or by an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydro

Abstract: A controlled release composition comprising an active substance other than a prostaglandin and a polymeric carrier therefor comprising residues having a ratio of number average molecular weight to functionality greater than 1000 which comprises polyethylene oxide and are cross-linked through urethane groups.

Abstract: A fibre-reinforced ceramic material is made by making a melt of glass of specified composition, cooling the melt rapidly enough for it to solidify as a glass, crushing the glass to a particle size not exceeding 70 .mu.m but preferably not exceeding 50 .mu.m mixing the powder with reinforcing fibres and heat-treating the mixture, preferably under pressure. The glass composition is: 100 parts by weight of base glass (0-30 CaO, 0-30 MgO, 5-35 Al.sub.2 O.sub.3, and 35-75 SiO.sub.2) plus 1/2-3 parts Cr.sub.2 O.sub.3 plus 1/2-10 parts of Fe.sub.2 O.sub.3 or the equivalent.This ensures the ceramic contains both surface-nucleated and internally-nucleated crystals, enhancing its properties.

Abstract: A magnetic field sensor including a body of amorphous magnetic material [C] and means to propagate ultrasound [A.B.D.] in said body together with means [E,F; PD, PSD, F] to detect variation with ambient magnetic field strength in the effect of the body on the propagation of ultrasound therein. The ultrasound is propagated as zero-mode shear wave, said mode being controlled by having the thickness of the body of amorphous magnetic material below a critical value which is the quotient of velocity divided by frequency. A specific magnetic field [G,J; G,M] can be applied to control the operating point of the sensor. The field can be alternating and the effect on propagation detected by a phase detector followed by a phase sensitive detector.

Abstract: An image of the distribution of the molecules of a paramagnetic substance in solution obtained by exciting EPR resonance in the solute and obtaining an NMR image of selected nuclei (e.g. protons) in the solvent.

Abstract: The invention relates to matching asymmetrical discontinuites 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 discontinuites, 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 quarterwave transformer".

Abstract: A method of determining one gas in the presence of another, where the one gas is reactive with an electrochemical product of the other, comprisesapplying the gases to one side of a membrane permeable to the two gases, the other side of the membrane retaining a solvent for both gases and for the electrochemical product,applying, for the predetermined duration through a working electrode in contact with the solvent, a potential which electrolyses (e.g. reduces) the (dissolved) other gas to form the said electrochemical product,applying, through the working electrode, a potential for reconverting the product to the dissolved gas,measuring, at a predetermined instant or integrated over a predetermined time slot, the current flowing at the reconversion potential, and,from the amount by which the measured current (or integrated current, i.e. charge) falls short of the current when the said one gas is absent, determining the concentration of the said one gas.

Abstract: In view of the introduction of cellular radio, there is a requirement for an antenna of simple construction which can be sold in a consumer market. While the invention meets this need it also has application to the problem of providing TM.sub.01 to TE.sub.01 made converters. The invention employs radial conductors printed on a dielectric substrate and aligned with the transverse electric field in a waveguide supporting the TM.sub.01 mode. Circumferential conductors, each coupled to one of the radial conductors, act as monopoles radiating the required field in an antenna where the radial conductors project through apertures in the waveguide. For the mode converter, both radial and circumferential conductors are inside the waveguide, with the radial conductors aligned with the transverse electric field of the TM.sub.01 mode. Arrangements for maximizing the field at the position of the radial and circumferential conductors are described as are means for preventing the propagation of unwanted modes.

Abstract: The detection of compounds containing both nuclei of a kind which exhibit nuclear magnetic resonance (nmr) and nuclei of a kind which exhibit nuclear quadrupole resonance (nqr), for example compounds containing both .sup.1 H and .sup.14 N nuclei, is carried out by subjecting a substance suspected of containing such a compound to a magnetic field and repetitively to three parallel activities A,H and B. Activity A comprises two similar rf pulse sequences P.sub.A and P.sub.B at the nmr frequency. Activity H is a temporary change in the value of the magnetic field, which may be a reduction to zero. Activity B is the application of additional rf signals. Activity H and/or activity B are different during each of the respective pulse sequences P.sub.A and P.sub.B. The activity B rf signals are at one or more frequencies selected so that in combination with the activity H in at least one of the pulse sequences the subsequent nmr signal is modified if such a compound is present.

Abstract: Polymeric materials useful as positive resists comprise a backbone formed from an addition polymer which is degradable by radiation and at least 3 pendant polymeric groups which show no appreciable positive resist characteristics. Preferably these materials comprise a backbone which is a polymethacrylate ester and from 3 to 5 pendant polystyrene groups. These polymers exhibit increased sensitivity and resistance to plasma processing and provide resists which are useful as components of integrated circuits.

Abstract: A composition which comprises at least one solid or liquid particle comprising at least one active substance, the or a plurality of such particles being encapsulated by the in situ cationic (co)polymerization there on of at least on cationically polymerizable monomer or prepolymer.

Abstract: A sustained release device which comprises a source of at least one trace chemical element incorporated in a cement and releasable therefrom on contact with an aqueous medium.The trace chemical element is exemplified by selenium, cobalt and iodine and the cement is exemplified by a phosphate cement.