Abstract: A method for conducting a nucleic acid amplification reaction, said method comprising forming an amplification reaction mixture in the presence of sufficient of a pyrophosphate salt to prevent primer extension taking place, digesting said pyrophosphate salt with a pyrophosphatase enzyme (PPase), and subjecting said reaction mixture to conditions such that an amplification reaction may proceed. This can be used as a “hot start” amplification. Particular novel pyrophosphatase enzymes for use in the method are also described and claimed.

Abstract: This invention describes an improved method and apparatus for the analysis of fluid borne particles and which is especially suitable for the detection of airborne biological particles. In one aspect of the invention provides an apparatus for the detection of fluid borne particles which comprises a zone through which a fluid to be analyzed flows in use, a source of illumination to illuminate/irradiate fluid borne particles present in said zone, and a detector to detect light from the particles as an indicator of the presence or characteristics of the particles, wherein the apparatus comprises an integrating sphere and the zone is within the integrating sphere. The apparatus is highly sensitive and can be used for detecting airborne particles even where the particles are present at very low particle concentrations in the air.

Abstract: A composition having immunosuppressant activity comprises at least one compound of the formula (I) in which R is an acyl group of the formula (II) wherein one of R1 and R2 is H and the other is selected from OR4, SR4 and NHR4, wherein R4 is H or 1-6C alkyl, or R1 and R2 together with the carbon atom to which they are joined form a keto group, and R3 is a straight or branched chain, saturated or unsaturated aliphatic hydrocarbyl group containing from 8 to 11 carbon atoms and is optionally substituted by one or more substituent groups selected from halo, 1-6C alkoxy, carboxy, 1-6C alkoxycarbonyl and NR5R6 wherein each of R5 and R6 is selected from H and 1-6C alkyl or R5 and R6 together with the N atom form a morpholino or piperazino group, or any enantiomer thereof; and at least one compound of the formula (III): wherein R7 is a straight or branched chain, saturated or ethylenically-unsaturated aliphatic hydrocarbyl group containing from 1 to 18 carbon atoms which may optionally be substituted by one or more su

Abstract: A recombinant microorganism comprises an asporogenic Bacillus subtilis strain in which a gene encoding a protease enzyme has been downregulated or inactivated. In particular sigma factorspoIIAC is inactivated such that the strain is asporogenic. These strains are particularly useful as expression vehicles for proteins such as protective antigen (PA) of Bacillus anthracis.

Abstract: An isolated protein, for use in treatment of wounds, is characterized in that it is secreted by the organism Lucilia sericata and it exhibits proteolytic activity against FITC-casein at a pH of 8.0 to 8.5. The protein exhibits proteolytic activity against Tosyl-Gly-Pro-Arg-AMC but not against Suc-Ala-Ala-Phe-AMC, and its proteolytic activity against FITC-casein and Tosyl-Gly-Pro-Arg-AMC is inhibited by the serine proteinase inhibitors PMSF and AMPSF. The protein is also bound by immobilized aminobenzamidine.

Abstract: A respirator (1) comprises an inner, oronasal, mask (2) enclosed within an outer, face sealing, mask (3) so as to define a cavity (4) therewith, a screw-threaded air inlet (5) for conducting inhaling air to the interior of the inner mask (2), a filter canister (7) for filtering the inhaling air, and an air outlet (8) for conducting exhaled air from the interior (6) of the inner mask (2). In normal operation, air is inhaled and exhaled solely through the inner mask (2) and so substantially no air pressure differential exists between the ambient atmosphere (9) and the cavity (4) which will allow ambient air to enter the cavity.

Abstract: A smart film or material which automatically controls its porous properties in relation to changes in its local environment thus allowing fluids to pass through the film or material in a controlled fashion.

Abstract: A method of aligning a liquid crystal includes a step of fixing on a hot plate and heating a liquid crystal cell in which a liquid crystal composed of a ferroelectric liquid crystal material sealed between electrode substrates respectively having alignment films having applied thereto a uniaxial alignment by rubbing. According to the described method, a pressure is applied to the liquid crystal cell by a roller, and a portion subjected to an application of pressure is moved by moving the roller. Further, the liquid crystal is heated within a temperature range between a phase transition temperature of SmA phase SmC* phase and a temperature 10° C. below the phase transition temperature, and the portion subjected to an application of pressure is moved in the same direction as the rubbing direction, thereby achieving the C2 orientation at higher yield.

Abstract: A bistable nematic liquid crystal device cell (1) is provided with a surface alignment grating on at least one cell wall (3) and a surface treatment on the other wall (4). Such treatment may be a homeotropic alignment or a planar alignment with or without an alignment direction, and zero or a non zero pretilt. The surface profile on the monograting is asymmetric with its grove height to width selected to give approximately equal energy within nematic material (2) in its two allowed alignment arrangements. The monograting may be formed by a photolithographic process or by embossing of a plastics material. The cell (1) is switched by dc pulses coupling to a flexoelectric coefficient in the material (2), or by use of a two frequency addressing scheme and a suitable two frequency material. Polarizers (13,13′) either side of the cell (1) distinguish between the two switched states. The cell walls (3,4) may be rigid or flexible, and are coated with electrode structures (6,7), e.g.

Abstract: The invention is directed to a solid walled hollow carbon fiber made from a hollow polyacrylonitrile fiber.

Abstract: A liquid crystal display element is arranged so that a scanning line electrode group and a signal line electrode group, which are formed by arranging a plurality of electrodes parallel, are placed in a direction where they intersect each other, and liquid crystal intervenes between these electrode groups, and input directions of signal voltages to be applied to the signal line electrode group are opposite in some electrode. As a result, nonuniformity of temperature on a display screen, which is caused by heat generation according to driving of the liquid crystal and causes variations of a driving property of the liquid crystal, is suppressed, and thus a satisfactory display state is realized.

Abstract: A ferroelectric liquid crystal display panel comprises an addressable matrix of pixels and an arrangement for selectively addressing each pixel within a series of addressing frames in order to vary the transmission level of the pixel relative to the transmission levels of the other pixels. The addressing arrangement utilizes a temporal dither (TD) addressing scheme for addressing each pixel within each frame with different combinations of temporal dither signals applied to separately addressable temporal bits within the frame to produce different overall transmission levels.

Abstract: Compounds of formula ##STR1## are provided which may be used in a variety of devices including liquid crystal devices, piezoelectric devices, pyroelectric devices and in optical recording media, wherein X.sub.1 and X.sub.2 are independently selected from H, CN, COCH.sub.3, CO.sub.2 CH.sub.3, m=at least 5; X.sub.3 and X.sub.4 are independently selected from formula (IA), ##STR2## wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH.sub.2 ; Q=(CH.sub.2).sub.n wherein one or more non-adjacent methylenes may be replaced by O and n=1-20; Z is selected from O, S, single covalent bond, COO, OCO; when Y is CH2 then n may also be O; formula (A) ##STR3## represents any mesogenic group; X3 and X.sub.4 are also independently selected from H, OH, OCOR.sup.1, COOH, CO.sub.2 R.sup.1 (CH.sub.2).sub.p OH, (CH.sub.2).sub.p CO.sub.2 H, --(CH.sub.2).sub.p OR.sup.1 or --(CH.sub.2).sub.p CO.sub.2 R.sup.1 and p=1-20, R.sup.1 =H or C.sub.1=16 alkyl, when R.sup.1 =C.sub.2-16 alkyl the terminal Ch.sub.

Abstract: A panel-form loudspeaker has a resonant multi-mode radiator panel which is excited at frequencies above the fundamental frequency and the coincidence frequency of the panel to provide high radiation efficiency through multi-modal motions within the panel, in contrast to the pistonic motions required of conventional loudspeakers. The radiator panel is a skinned composite with a honeycomb or similar core and must be such that it has a ratio of bending stiffness to the third power of panel mass per unit area (in mks units) of at least 10 and preferably at least 100. An aluminum skinned, aluminum honeycomb cored composite can meet this more severe criterion easily.

Abstract: A passive liquid crystal device (FIG. 1) is driven in a multiplexed manner by a strobe signal (STB) applied in succession to a plurality of row electrodes and data signals (DATa, DATb) applied to a plurality of column electrodes. A resultant signal (RESa, RESb) comprising the combination of the strobe and data signals is applied to the pixels in the device. The liquid crystal device is sensitive to the polarity of the resultant signal. Typically a blanking pulse of a first polarity is applied followed by a resultant signal of the opposite polarity. A first data signal (DATa) is intended to change the state of the relevant pixel (SELECT) while a second data signal (DATa) is intended to leave the pixel in the same state (NON-SELECT). According to the invention the resultant signal (RESa, RESb) comprises at least a portion which is substantially continuously varying. This can be achieved by either or both of the strobe and data signals including such a portion or portions.

Abstract: A method for manufacturing a liquid crystal display element is provided. A plurality of electrodes having a light-transmitting property are formed in a striped pattern on one surface of an insulating substrate having a light-transmitting property. Then, light-shielding films are formed in such a manner that the light-shielding films are formed adjacent to the edges of each electrode along the long sides thereof, or at least one portion of each light-shielding film is made to overlap each edge of the electrode along one of the long sides thereof. Successively, light is applied from the back-surface side of the insulating substrate by using the light-shielding films and a photomask as masks so that spacers are formed in a state where they are self-aligned with respect to the light-shielding films.

Abstract: An information processing system (10) receives input data from a keyboard (26), a mouse (28) and spoken data input device (30) in an input data sequence. A microphone (32) converts received speech into electrical signals which are digitized by an analogue to digital converter (100). A digital signal processor (102) converts the digital signals into multi-dimensional vectors which are stored in a temporary input buffer (104). A recognition processor (106) performs a recognition program in order to match the multi-dimensional vectors to speech models. In order that the system (10) may output data in an output data sequence which corresponds to the input data sequence, each data input receives a time stamp. A timing controller (24) ensures that instructions received from either the keyboard or the mouse are output only when those instructions have a time stamp which is earlier than the time stamp of the data most recently processed by the recognition processor.

Abstract: A spread spectrum signal detection system comprising two spatially separated receivers, a correlator, such as a time integrating correlator employing acousto-optic cells, which is connected to the outputs from the two receivers to produce a signal representative of the cross correlation function of the two spread spectrum signals, a filter arranged to transmit only the central portion of the cross correlation function and a signal processor to produce the cross spectral density and thereby determine the presence of the spread spectrum signal. The direction of arrival of the spread spectrum signal can be determined by measurement of the angle of the phase slope of the cross spectral density. The acousto-optic cells can be Bragg cells.

Abstract: A method is provided for separating one or more volatile contaminant components from a gas using a pressure and temperature swing adsorbent filtration filter bed system containing three or more layers of adsorbent materials characterized in that the layers comprise a first layer of adsorbent material, a second layer of dessicant material and a third layer of material capable of adsorbing contaminants that are not retained by the first layer. Preferably the third layer is capable of adsorbing contaminants of relatively low boiling point, e.g. of boiling point less than 50.degree. C., and preferably comprises a microporous adsorbent. The second layer of dessicant material preferably comprises a zeolite.