Abstract: Materials of formula (I): [G]g(SiO1/2)x are described where G is R3SiR1R2(O)k; R1, R2, R3 are independently a C1-16 alkyl which may be partly or fully halogenated, H and formula (IA), wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH2; Q=(CH2)n where one or more non-adjacent methylenes may be replaced by O and n=1=20; Z is O, S, a single covalent bond, COO, OCO; when Y is CH2, then n may also be 0; (a) represents any mesogenic group; provided that at least one of R1, R2, R3, is selected from formula (IA): k=0 or 1; g=4 or 6 or 8 or 10 or 12; 1=3 or 8 provided that: if k=1, 1=3 and x is selected form 6, 8, 10, 12 then g=x; if k=0, 1=8 and g=4 then x=1; and further provided that G may have up to g different structures for any single compound.

Abstract: A collision warning system (10) discriminates between objects which pose a threat of collision from those which do not by measuring the relative sightline rate of the object, this being a measure of the rate of change of angular position of the object if the sightline rate is above a threshold value, there is little risk of collision. To measure the sightline rate, a radar source (20) emits microwave frequency radiation which is received by two detectors (22 and 24) after reflection from a target. Signals from the detectors are processed by processing means (26). The processing means determines if the sightline rate of an object is below a certain threshold. If it is, and the relative velocities of the object and the system are such that a collision is likely, a warning buzzer (28) sounds.

Abstract: An enzymically active cell free extract or membrane fraction capable of catalysing the removal of nitrite from hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is provided. The cell free extract is produced by culturing a strain of Rhodococcus rhodochrous bacterium from nature. The strain designated 11Y has been deposited as NCIMB 40820. Methods of bioremediation using the enzymically active cell free extract so produced are also provided. Additionally there is provided a method for detecting the presence of RDX in a sample together with a biosensor for use in such a method. The nitrite produced in the enzyme catalysed reaction with RDX is detected, for example, colorimetrically, or alternatively a product of RDX degradation, such as formal behyde, is detected.

Abstract: A method and an apparatus for distinguishing systematic artifacts from noise involves localizing functional noise in the vicinity of predicted functional peaks. The method is particularly relevant to detection and tracking of time-varying signals. An apparatus implementing such an application of the method comprises a detection system (50) which monitors each component of a multi-component periodic signal via its basis repeat unit: a cyclet, of periodicity &tgr;. The signal is digitized and clocked through the system (50) in segments. A cyclet remover (62) subtracts predicted values of previously detected cyclets from the incoming signal segment to produce a residual signal. A cyclet detector (60) uses a sliding window procedure to detect further cyclets in this residual and to measure their amplitude profiles {overscore (b)}(&tgr;) and periodicities (&tgr;).

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 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: An electrolyte comprises a composite of a polymer and a molten salt electrolyte immobilized within the polymer. The electrolyte is stable and ionically conducting at a temperature substantially equal to the melting point of the molten salt electrolyte. In this form, the electrolyte is suitable for use in electrochemical cells, supercapacitors or electrochromic windows and displays.

Abstract: The present invention relates to protection agents, in particular to topical compositions such as barrier creams which can prevent the passage of toxic chemicals and chemical warfare agents through the skin. Formulations contain hexamethylene tetramine derivatives or analogues thereof and perfluorinated polymeric compounds.

Abstract: In order to reduce the effects of impact on liquid crystal devices a polymer network is introduced into ferroelectric liquid crystal cells. A liquid crystal device comprises two spaced cell walls each bearing electrode structures and treated on at least one facing surface with an alignment layer, a layer of a smectic liquid crystal material enclosed between the cell walls, characterised in that the liquid crystal material contains a small amount of monomer. The liquid crystal material may also contain a photoinitiator. The monomer material may be cured to produce the polymer networks the curing many be carried out in the presence of an electric or magnetic field. Further, the monomer may be cured in an isotropic or liquid crystal phase.

Abstract: An optical filtering device incorporates first and second prisms, the latter prism counteracting the angular dispersion of the former prism. A spatial light modulator provides a positionally variable optical stop located to block radiation within a wavelength interval and received from a location within a scene. Unobscured radiation from that and other scene locations passes to a camera, which produces an image on a display. Opaque pixels in the stop are positioned to block unwanted light sources. The invention attenuates potentially dazzling monochromatic radiation while retaining radiation at other wavelengths for imaging purposes.

Abstract: This invention describes a method by which microparticles, typically in the size range from 0.3 &mgr;m to 100 &mgr;m, which are carried in a fluid suspension, may be rapidly detected and characterized. The method primarily relates to the measurement of atmospheric particles such as those in clouds or environmental aerosols, but it may be used to measure other forms of particulate suspension wherever the flow of suspension through a defined measurement space can be achieved. The method is based upon a rapid analysis of the spatial laser scattering profile (i.e., the complex manner in which individual particles scatter laser light) recorded from individual particles as they are carried in suspension through a measurement space. Using this method it is possible to differentiate various types of particles based on particle shape and structure, as manifest in characteristics of their individual spatial light scattering patterns.

Abstract: Compounds of formula (I) are provided which are particularly useful in super twisted nematic devices, where n may be 0-5; m may be 0-5; p may be 1-9; q may be 1, 1, or 2; A1, A2 are independently chosen from 1-4, -disubstituted benzene, 2,5-disubstituted pyrimidine, or 2,5-disubstituted pyridine, trans- 1,4-disubstituted cyclohexane, trans- 2,5-disubstitued dioxane. The aromatic rings may be laterally substituted with F, Cl, Br or CN; Z1 may be O, COO, OOC; Z2, Z3 are independent chosen from a direct bond, COO, OOC, C2H4, CH2O, OCH2, or -c≡c-, provided that when Z1 is O and m is 1, 3 or 5 the carbon—carbon double bond configuration is E; provided that when Z1 is O and m is 2 or 4 the carbon—carbon double bond configuration is Z; provided that when Z1 is COO or OOC and m is 0, 2 or 4 the carbon—carbon double bond configuration is E; and provided that when Z1 is COO or OOC and m is 1, 3 or 5 the carbon—carbon double bond configuration is Z.

Abstract: A group fo liquid crystalline compounds defined by formulas (1) and (2) including polymers, monomers, oligomers and intermediates for their preparation. Also included are symmetric and non-symmetric poly(dimethylsiloxy) compounds having end groups derived from Formulas (1) and (2).

Abstract: Methods, based on the Wittig-Horner reaction, are provided for the synthesis of compounds of formula (I) where m is from 5-150, X and Y are independently selected from: CN, H, OH, COCH3, CO2H, CO2H, CO2R1, where R1 is C1-12 alkyl, NCS, SCN, CF3, CH2X where X is F, Cl, Br, OH, CHF2 and formula (IB), where J for each X and Y group is independently selected from: CH2, single covalent bond, OOC, CO2, O, CH2O, OCH2, CH2CO2, CH2OOC; p=1-20; L for each X and Y group is independently selected from: O, CH2OCO, CO2, S, NH; (a) is defined by formula (IC), where rings A, B and C are independently selected from phenyl, cyclohexyl, pyridine and pyrimidine and may be independently of each other substituted with at least one of Cl or F; linking groups A and B may be selected from single bond, CO2, OOC, CH2O, OCH2, CH2CH2, C≡C; Z is selected from CN, F, Cl, NO2, R, OR, CO2R, CF3, OOCR, NCS, SCN, where R=straight chain or branched chain alkyl and may include from 1-16 carbon atoms and incl

Abstract: A segmented electrode drive circuit of a passive-matrix type liquid crystal display apparatus includes one analog switch in each of segmented electrodes, supplies “0” as a control signal in the first slot of a three-slot selecting period so as to make the electrical potential of a segmented electrode zero. “1” is supplied as a control signal in the second slot so as to bring the output terminal of an analog switch selected by the data signal into a high-impedance state. As a result, the electric potential of the segmented electrode in the high-impedance state becomes an average electric potential of scanning electrodes capacitive-coupled with the segmented electrode.

Abstract: A non-mechanical modulating device for use in infrared detection. The device is of particular use in the 8-14 &mgr;m range and has application in thermal imaging cameras and gas sensing systems. The modulator comprises a germanium element and a means of varying the carrier concentration. In particular, the variation of the hole concentration gives rise to the absorption of infrared radiation due to interband transitions between the light and heavy hole bands in the split valence band in germanium. The variation in hole concentration may be initiated in any convenient way, for example, by the irradiation of the germanium with visible or near infrared light, by the electrical injection of free carriers across a germanium diode structure or by electron impact on the germanium surface following acceleration under vacuum. In the case where the variation in carrier concentration is initiated by optical means, the surface of the germanium is treated so as to produce a low surface recombination velocity.

Abstract: A thermal imaging system (10) which is accoupled and by scanning recreates a thermal image by superimposing measured variations in infrared emission from a scene (22) onto a reference level supplied by a light emitting diode (28). The diode (28) is both a positive and negative luminescent emitter. Emitted flux is current controlled to be equivalent to black body radiation at a range of temperatures which may be colder or hotter than ambient. A signal generated with the system (10) switches between scene and diode observation is a measure of the difference between the mean scene temperature and the diode effective temperature. In response to this digital, control means adjust the bias current through the diode (28) in order to reduce the temperature difference. The reference temperature converges towards the mean scene temperature as this process is repeated. Absolute temperature is thus restored and some image defects removed.

Abstract: Proteins are provided having luciferase activity with lower Km than wild-type luciferases by altering the amino acid residue at position 270 of the wild-type to an amino acid other than glutamate. Greater heat stability than wild-type luciferases while retaining the lower Km is provided by also replacing the glutamate equivalent to that at position 354 of Photinus pyralis luciferase or 356 of Luciola luciferases with an alternative amino acid, particularly lysine and/or the amino acid residue at 215 of Photinus pyralis and 217 of the Luciola species with a hydrophobic amino acid. DNA, vectors and cells that encode for and express the proteins are also provided as are test kits and reagents for carrying out luminescence assays using the proteins of the invention.

Abstract: A mixture of a ferroelectric or anti-ferroelectric liquid crystal material and a monomer having a single photopolymeric functional group is injected in the space between two electrode substrates while heat is applied. After cooling of the mixture it is irradiated with ultraviolet light at a temperature at which the liquid crystal material remains in the smectic phase so as to polymerise the monomer. Areas of liquid crystal material requiring different threshold voltages for switching are thereby produced. Alternatively such areas can be produced by changing the conditions applied to a mixture of liquid crystal material with a suitable dopant so as to cause separation of the dopant out of the liquid crystal material in order to provide a polarity of nucleation points for controlling domain formation within the liquid crystal material. Such control of domain formation can be used to provide greyscale in a liquid crystal device.

Abstract: A light modulating device, such as a ferroelectric liquid crystal display (FLCD) comprises an addressable matrix and modulating elements or pixels and associated circuitry for selectively addressing each element in a series of addressing frames in order to vary the transmission level of each element relative to the transmissions levels of the other elements. Such addressing utilises a temporal dither addressing scheme for addressing at least part of each element within each frame with different combinations of temporal dither signals applied to separately addressable temporal bits within the frame to produce different transmission levels. In order to enable a large number of grey levels to be produced whilst limiting the perceived errors at transitions between different grey levels, the temporal bits are addressed in a first order in a first frame (or in a first spatial location) and in a second order, which is different to the first order, in a second frame (or in a second spatial location).