Abstract: The present invention is based on the finding that the artificial induction of hepatic stellate cell (HSC) apoptosis in vivo can promote the resolution of liver fibrosis. Thus, the present invention provides methods for treating liver disease in a subject involving administration of an inducer of apoptosis which is capable of selectively inducing hepatic stellate cell apoptosis in the liver of the subject or of an agent which is capable of giving rise to such an inducer in the subject. In addition, the invention provides methods for treating liver fibrosis in a subject comprising the selective delivery of an inducer of apoptosis specifically to the hepatic stellate cells of the subject or of an agent which is capable of giving rise to an inducer of hepatic stellate cell apoptosis.

Abstract: A source of pulses of coherent radiation at a wavelength of approximately 1 ?m, comprises a pump source for producing pump light, a laser cavity comprising an Yb3+-doped gain medium arranged to receive the pump light, the laser cavity being modelocked to generate laser pulses at a defined repetition rate; a pulse detector arranged to generate a pulse selection signal indicative of the repetition rate; a pulse selector arranged to reduce the repetition rate of the laser pulses responsive to the pulse selection signal from the pulse detector by passing only selected ones of the laser pulses; and at least one optical amplifier for amplifying the laser pulses of reduced repetition rate. The at least one optical amplifier can be configured for chirped or parabolic pulse amplification.

Abstract: An optical fibre device based on the Raman effect comprises a first optical source to provide light at a first wavelength, and a holey optical fibre which receives the light from the first optical source such that optical gain or loss is provided at a second wavelength by the effect of Raman scattering within the fibre. For optical gain, the second wavelength is longer than the first wavelength, and the device can be operated as an amplifier, or as a laser if optical feedback is provided. For optical loss, the second wavelength is shorter than the first, and the device may be used as an optical modulator. The fibre may be fabricated from pure silica, although other undoped or doped materials may alternatively be used to tailor properties of the fibre such as gain spectrum, bandwidth, power handling capability and mode propagation.

Abstract: A broadband laser source comprising: a resonant cavity (1) containing a medium (2) which emits optical energy (3) in a continuum of wavelengths in response to application of pump energy (4) to the medium (2); a source of pump energy (5) for producing said optical energy (3); a frequency shifter (6) within the resonant cavity (1); and a tuneable spectral filter (7) within the resonant cavity (1), and the apparatus being such that in use the tuneable spectral filter (7) has a peak wavelength which is repeatedly swept in a substantially resonant fashion over a wavelength range equal to, or a fraction of, a linewidth of the broadband source such that the rate of change of the peak wavelength of the tuneable spectral filter (7) is substantially equal to the rate of change of the frequency of the optical energy (3) as it is frequency shifted within the resonant cavity (1) by the frequency shifter (6).

Abstract: An apparatus and method for dispersing a volatile composition, which method comprises dispersing the volatile composition into an air steam; and generating an ion wind, thereby causing the molecules of the composition to become electrically charged.

Abstract: A method of creating a varying second order non-linearity profile along a waveguide, comprising: providing a waveguide structure with a waveguiding core and a surface adjacent to the waveguiding core; structuring the surface to produce a structured surface defining a varying distance between the structured surface and the waveguiding core along the waveguide; and thermally poling the waveguide structure to generate a varying second order non-linearity profile along the waveguide-derived from the varying distance between the structured surface and the waveguiding core. By the surface structuring the modulation of the second order non-linearly induced by the thermal poling can be enhanced. The waveguide structures can be used for making a variety of quasi-phase-matched (QPM) devices.

Abstract: An optical fibre arrangement has at least two optical fibre sections, each optical fibre section defining an outside longitudinally extending surface. The outside longitudinally extending surfaces are in optical contact with each other. The invention further provides for an amplifying optical device have an optical fibre arrangement as just described, and a pump source. The amplifying optical device is configured such that the pump source illuminates the amplifying optical fibre. A amplifying arrangement is also disclosed. The amplifying arrangement includes a plurality of amplifying optical devices as just described, and each amplifier also has at least one input fibre and a first multiplexer connected to the input fibre. Each amplifier is configured such that at least one of the amplifying optical fibres is connected to the first multiplexer. The amplifying arrangement also has a second multiplexer connected to each of the first multiplexers.

Abstract: A tellurite glass material has a composition of Li2O:TiO2:TeO2, and contains a dopant comprising ions of a rare earth metal. The rare earth ions can be thulium ions, Tm3+, to provide a material offering optical gain at 1470 nm. The properties of the glass make it suitable for the fabrication of high quality optical fibers and planar waveguides, which can in turn be used in optical amplifiers and oscillators. Co-doping the glass with acceptor ions such as holmium ions, Ho3+, improves the population inversion in the rare earth ions and hence enhances the gain.

Abstract: A technique of reducing the Peak-to-Average Power Ratio (PAPR) of Multi-Carrier (MC) modulated signals in which peaks in the baseband signal that lie above a threshold amplitude are detected and used to generate a pulse sequence signal which, after shaping, is subtracted from the baseband signal to reduce its PAPR. The method is spectrally efficient, has a low degree of implementation complexity and hence it is also suitable for low-power, portable implementation. Moreover, it is compatible with existing standard-based Orthogonal Frequency Division Multiplex (OFDM) systems. As an example of the performance of the proposed scheme, the amplifier back-off requirement in a Terrestrial Digital Video Broadcast (DVB-T) system can be reduced from 12 to 6 dB, while satisfying the of out-of-band emission specifications imposed by the Federal Communications Commission (FCC) spectral mask.

Abstract: A source of optical pulses, comprises an optical source operable to generate ultrashort optical pulses at a first wavelength; and an optical fiber amplifier comprising an optical fiber having a core containing a dopant to provide optical gain at the first wavelength and anomalous dispersion over a wavelength range including the first wavelength and a second wavelength. The optical fiber receives the ultrashort optical pulses, amplifies the ultrashort optical pulses, and alters the wavelength of the ultrashort optical pulses to at least the second wavelength by the soliton-self-frequency shifting effect. Microstructured and/or tapered fibers can be used to provide the required dispersion characteristics. Pulses can be generated in one of three spectral regimes—monocolor solitons, multicolor solitons and continuous broadband spectra by adjusting the energy of the optical pulses, and tunability can be achieved by varying the power of pump light provided to the amplifier.

Abstract: A new and improved hybrid of Ga:La:S (GLS) glass is provided, namely a glass comprising gallium sulfide, lanthanum oxide, and at least 2 mol % lanthanum fluoride. The Ga:La:S:O:F (GLSOF) glass retains the important properties of the Ga:La:S system, while introducing improved thermal stability and spectroscopic properties. In addition, GLSOF glasses are non-toxic. The glass formation region for GLSOF has been carefully evaluated with compositional variations. It has been identified that an area of glass formation as indicated by circles, is a new and previously undiscovered glass formation region.

Abstract: An optical parametric device for broadband parametric processes involving first and second frequencies &ohgr;1 and &ohgr;2. The device comprises an optical fiber comprising a core and a cladding, the cladding being microstructured with holes for providing waveguiding confinement of at least one optical mode in the core. The optical fiber is poled lengthwise with a non-linearity profile having a period that satisfies a quasi phase matching (QPM) condition including the first and second frequencies. Through the use of a poled holey fiber of suitable hole structure, it is possible to increase the second harmonic (SH) efficiency in comparison with poled conventional (non-holey) fiber. This is achieved by a combination of a low mode overlap area between the fundamental and SH waves, a low absolute value of the mode area, and a large SH bandwidth per unit length of the fiber, all of which can be provided together in a poled holey fiber.

Abstract: Compounds of formula (I) wherein: Q represents an amidino group, a cyano group or a group of formula XYN—, (where X and Y are hydrogen or various groups); Ra represents alkylene; Rb and Rc each represents alkylene, the total number of carbon atoms in said straight chains of Rb and Rc being 7); R2 and R3 each represents hydrogen, or a group of formula R, RCO—, ROCO—, or RNHCO—, where R represents alkyl or aryl; the chiral carbon atom indicated by the asterisk is in the L configuration; Z is an aromatic amino acid residue; n is 0 or 1; R1 represents hydrogen, alkyl or aryl; and W represents hydrogen, alkyl or aryl; and pharmaceutically acceptable salts thereof have the ability to protect against the neuronal damage which may be caused by an ischemic event.

Abstract: A method of dispersing a volatile composition which method comprises dispersing a volatile composition into an air steam; and generating an ion wind, thus causing the molecules of the volatile to become electrically charged. An apparatus for use in the method is also disclosed.

Abstract: A method of fabricating a band-processing optical fibre filter having a center wavelength &lgr;0′, the method comprises (i) radius-reducing a mismatched multi-core optical fibre having a core phase matching wavelength (before radius reduction) of &lgr;0 and a radius (before radius reduction) of a0, to a reduced radius Ra0, where R=&lgr;0′/&lgr;0; and (ii) providing light input and output connections to a section of the radius-reduced multi-core fibre so that input light is launched into one of the cores of the multi-core fibre section and output light emerges from one of the cores of the multi-core fibre section.

Abstract: An apparatus and method for dispersing a volatile composition, which comprises dispersing the composition into an air stream and generating an ion wind, thereby causing the molecules of the composition to become electrically charged. The composition can be an insect repellent, an insecticide, an anti-microbial, an anti-allergenic or a room-fragrancing composition.

Abstract: The invention concerns an alkaloid glycoside for use in medicine. In a preferred aspect, the alkaloid glycoside is used for the stimulation of a class I-restricted immune response and/or a class II-restricted immune response. In a preferred aspect, the alkaloid glycoside is tomatine.

Abstract: A method of micro-structuring a surface of a sample of ferroelectric material, the method comprising: (a) taking a sample of ferroelectric material having a −z face which is to be etched; (b) illuminating the −z face with ultraviolet light to define illuminated and unilluminated parts of the surface; and (c) immersing the −z face in an etchant to selectively remove the unilluminated parts of the −z face at a greater rate than the illuminated parts. The method can be carried out using pulsed ultraviolet light to etch lithium niobate crystals cut for etching on the −z face, and may further be combined with ablation to produce multi-level surface structures.

Abstract: Optical waveguides having a waveguide channel of photosensitive silica glass with a modified refractive index optically written therein, wherein the photosensitive glass comprises oxides of silicon, tin and at least one Group I element, where such optical waveguide devices include optical fiber gratings, optical fiber dispersion compensators, optical fiber sensors, optical fiber lasers, and planar waveguide devices.

Abstract: Optical code division multiple access (OCDMA) coder:decoder gratings have been fabricated. The modulated refractive index profile that makes up the OCDMA coder:decoder grating incorporates changes in polarity between OCDMA chips by discrete phase shifts, thereby to provide bipolar coding through phase modulation. (In another embodiment quadrupolar coding is achieved). For NRZ modulation, each grating section is either in phase with, or has a predetermined phase shift relative to, the preceding grating section, depending on whether the OCDMA signature has a change in polarity between chips. RZ modulation is also possible. Results are presented from specific examples of bipolar OCDMA with NRZ modulation, which show higher data rates (10 Gbit/s), shorter chip-lengths (6.4 ps) and far longer code sequences (63 bits) than previously demonstrated. Other embodiments relate to optical packet switching, for example using the Internet Protocol (IP) or Asynchronous Transfer Mode (ATM).