Abstract: A composition comprising a plastics material, an inorganic particulate solid such as aluminium trihydrate and a coupling modified of formula A-(X—Y—CO)m(O—B—CO)nOH wherein A is a moiety containing a terminating ethylenic group with one or two adjacent carbonyl groups; X is a direct bond, O or N; Y is C1-18-alkylene or C2-18-alkenylene; B is C2-6-alkylene; m is from 1 to 4 and n is from 0 to 5 provided that when A contains two carbonyl groups adjacent to the ethylenic group then X is N. Specific examples of coupling modifiers are ?-carboxyl ethylacrylate and 5-carboxy pentyl maleimide.

Abstract: In a data link communications system there is provided a dual mode of operation multiple access system for communication between a plurality of spoke stations and a central hub station which generates a spoke epoch time comprising a plurality of time division slots in which a spoke station can communicate a priority interrupt request to the central hub station. The spoke epoch time comprises one or more dedicated spoke time slots in which only one hub station may transmit to the hub station to the exclusion of all other spoke stations. The spoke epoch time further comprising one or more priority interrupt request time slots in which all spoke stations can transmit priority interrupt requests to the hub station. Controller means in the hub station provides for evaluating priority interrupt requests from the spoke stations and for granting transmission access to one of said spoke stations during predetermined time slots in the next spoke epoch time.

Abstract: Digital circuitry, for use for example in a mixed-signal device such as a digital-to-analog converter, has decoders (22, 24) which process a digital input word (D1˜Dm) to derive thermometer-coded signals (T, {overscore (T)}) for controlling one cell of an array of cells in the device. The decoders commence operation at the rising edge of a first clock signal (DIGCLK). Each cell has a first, D-type latch (26) clocked by a second clock signal (CLK2) that is delayed by a preselected delay time &Dgr;1 relative to the first clock signal, and a second, transparent latch (32) clocked by a third clock signal (CLK3) whose rising edge coincides with the rising edge of the first clock signal and whose falling edge coincides with the rising edge of the second clock signal. The rising edge of the third clock signal is not affected by jitter associated with a delay element (28) used to delay the first clock signal by &Dgr;1.

Abstract: A fault-tolerant transaction processing system and method stores records associated with operations of the system in order to permit recovery in the event of a need to roll back a transaction or to restart the system. At least some of the operational records are stored as a recovery log in low-speed non-volatile storage and at least some are stored as a recovery list in high speed volatile storage. Rollback of an individual transaction is effected by reference to the recovery list whereas restart of the system is effected by reference to the recovery log.

Abstract: In a data link communications system there is provided a dual mode of operation multiple access system for communication between a plurality of spoke stations and a central hub station which generates a spoke epoch time comprising a plurality of time division slots in which a spoke station can communicate a priority interrupt request to the central hub station. The spoke epoch time comprises one or more dedicated spoke time slots in which only one hub station may transmit to the hub station to the exclusion of all other spoke stations. The spoke epoch time further comprising one or more priority interrupt request time slots in which all spoke stations can transmit priority interrupt requests to said hub station. Controller means in said hub station provides for evaluating priority interrupt requests from said spoke stations and for granting transmission access to one of said spoke stations during predetermined time slots in the next spoke epoch time.

Abstract: A technique of logging updates to a plurality of data records into discrete pages in non-volatile storage, wherein a page partially full of data is known as a partial page. Identical partial pages I and I+1 are established in the logging process as quickly as possible. Thereafter, in response to a data segment D larger than the remaining space of a most recent updated partial page I, D is partitioned into a first segment D1 sufficient to fill the remaining space of page I and a second data segment D2. Page I is updated with a first write operation to its present contents concatenated with D1, and identical partial pages containing D2 are created at I+1 and I+2 with a second write operation, whereby those pages become pages I and I+1 for the next logging operation.

Abstract: A mixed-signal integrated circuit device comprises a digital circuitry portion (DIGITAL) including digital circuitry (10) and an analog circuitry portion (ANALOG) including analog circuitry (14). The digital circuitry produces plural first digital signals (T1-Tn). The analog circuitry produces one or more analog signals (OUTA, OUTB) in dependence upon received second digital signals (TCK1-TCKn). The device also comprises a signal control circuitry portion (LATCH) including signal control circuitry which derives the second digital signals (TCK1-TCKn) from the first digital signals (T1-Tn) and controls the timing of application of the second digital signals to respective inputs of the analog circuitry. To avoid jitter in the second digital signals arising from power supply loading changes, power is supplied independently to each of the circuitry portions (DIGITAL, LATCH and ANALOG).

Abstract: Cell array circuitry (20) includes a cell array (22) made up of a plurality of current-source cells (2) arranged in rows and columns. The cells of the array are assigned respective ordinal positions in a predetermined selection sequence conforming, for example, to a so-called “magic square”. The assigned ordinal positions are such as to tend to equalise the respective sequence-position sums for different rows of the array and/or to tend to equalise the respective sequence-position sums for different columns of the array, where the sequence-position sum for a row or column is determined by summing the respective ordinal positions of the cells in the row or column concerned. Switch circuits (41 to 416) select those cells whose assigned ordinal positions are less than an applied value (e.g. 3). Respective currents produced by the selected cells are accumulated as an output current (IA) on a summing path (A).

Abstract: Coding circuitry (34), for use for example in selecting cells of a cell array in a digital-to-analog converter, produces first and second sets of thermometer-coded output signals in dependence upon a binary input signal. As the input signal increases progressively in value from a first value to a second value, the first-set output signals (COLA) are activated in a predetermined sequence and the second-set output signals (COLB) are deactivated in a predetermined sequence. As the input signal increases progressively in value from the second value to a third value, the first-set output signals are deactivated in a predetermined sequence and the second-set output signals are activated in a predetermined sequence.Such coding circuitry reduces the numbers of output signals that change in response to changes in the input-signal value.In another embodiment (FIG. 12) the coding circuitry includes respective row, column and depth decoders (58, 56, 54).

Abstract: A fault-tolerant transaction processing system and method stores records associated with operations of the system in order to permit recovery in the event of a need to roll back a transaction or to restart the system. At least some of the operational records are stored as a recovery log in low-speed non-volatile storage and at least some are stored as a recovery list in high speed volatile storage. Rollback of an individual transaction is effected by reference to the recovery list whereas restart of the system is effected by reference to the recovery log.

Abstract: Strains of Pseudomonas putida selected from Pseudomonas putida NCIB 12190 and mutant strains thereof, which mutant strains can be obtained by chemical and physical mutation, allowing the mutated bacteria to grow prior to exposure to benzene or fluorobenzene, and subsequently, after further growth in the presence of benzene or fluorobenzene, selecting those mutant strains which accumulate cis-dihydroxycyclohexadiene or catechol or their fluorinated analogues. The new strains can be used in biochemical processes for the preparation of cis-dihydroxycyclohexadienes and catechols.

Abstract: Certain novel alkenyl-substituted dihydroxycyclohexadienes and the corresponding catechols are prepared by providing a culture of a microorganism selected from P.putida NCIB 12190 and mutants thereof, supplying to the culture the corresponding benzene derivatives in suitable fermentation medium, and subsequently recovering the desired dihydroxycyclohexadiene in cis-relationship, optionally followed by dehydrogenating the compound to afford the corresponding catechol.

Abstract: Novel compound cis-1,2-dihydroxy-3-trifluoromethylcyclohexa-3,5-diene (and certain fluoro-substituted analogues) can be produced biochemically by culturing a wild type or mutant strain of P.putida with benzotrifluoride or certain fluoro-substituted analogues as substrate.

Abstract: Strains of Pseudomonas putida selected from Pseudomonas putida NCIB 12190 and mutant strains thereof, which mutant strains can be obtained by chemical and physical mutation, allowing the mutated bacteria to grow prior to exposure to benzene or fluorobenzene, and subsequently, after further growth in the presence of benzene or fluorobenzene, selecting those mutant strains which accumulate cis-dihydroxycyclohexadiene or catechol or their fluorinated analogues. The new strains can be used in biochemical processes for the preparation of cis-dihydroxycyclohexadienes and catechols.

Abstract: A process for the preparation of a catechol and/or a compound comprising a 1,2-dihydroxycyclohexa-3,5-diene ring, which comprises growing a microorganism in the presence of a carbon source, the microorganism being capable of converting the corresponding aromatic compound into the catechol and/or the compound comprising a 1,2-dihydroxycyclohexa-3,5-diene ring; and supplying the corresponding aromatic compound to the microorganism; characterized in that the carbon source is molasses.

Abstract: In a surface acoustic wave device including launching and receiving transducers (2, 3) and a reflective multistrip coupler (4), the inner boundaries of the input and output electrode arrays (5, 6) of the reflective coupler (4) are defined both electrically and acoustically by an electrically discontinuous strip (23) formed for example by isolated islands of metalization (24) in conjunction with corresponding adjacent portions of interconnecting conductors (16). This enables the effective apertures of the input and output arrays (5, 6) to be better matched to the transducers (2, 3). The arrangement can reduce the insertion loss in low-loss SAW devices (i.e. in which both ends of the transducers (2, 3) are coupled via corresponding reflective couplers (4)) and also in single symmetrical guided mode SAW devices in which the strip 23 can provide an effective inner guiding bus bar whose surface mass loading corresponds to that of the outer bus bars (9, 10).

Abstract: In a surface acoustic wave device which includes a relfective multistrip coupler (4, 4'), direct electrical breakthrough resulting from the adjacent location of the input and output transducers (2, 3) is reduced by including at least one forward multistrip coupler (24,25) in each path coupling the transducers (2,3) via the reflective couplers (4,4') so as to space the transducers (2,3) from one another. In a so-called low-loss device in which both ends of the transducers (2,3) are reflectively coupled, the arrangement enables the input/output track separation (23) of the reflective couplers to be reduced thereby significantly reducing the insertion loss of the device.

Abstract: An improvement to the reflective multistrip coupler of the surface acoustic wave device described in EPA No. 0098661 for overcoming the k-determined bandwidth limitation wherein, instead of being uniform, the electrode spacing is varied correspondingly along the input and output arrays of the coupler with the result that different frequency bands will be reflected by different groups of electrodes. At least two reflective couplers (24, 25) with complementary spacing variations are included in the path coupling the input and output transducers (2, 3) so that all frequencies in the overall passband have substantially the same overall time delay. Contiguous bands of frequencies f.sub.1, f.sub.2, f.sub.3, f.sub.4 may be reflected by individual related groups 26, 27, 28, 29 of uniformly spaced electrodes forming either a monotonic or a permutated sequence, or the spacing can be varied continuously and monotonically.

Abstract: A low insertion loss surface acoustic wave filter in which withdrawal weighted launching and output transducers 20, 40 are acoustically coupled by two high efficiency reflective multistrip couplers 6, 6'. To reduce the insertion loss, the inner bus bars 21, 41 are reduced in width so as to reduce the dead space 12 in the coupler. This makes it impossible to form a reliable wire bond connection to the inner bus bars which are therefore connected via a conducting path across the propagation path at the ends of the transducers. Further reduction in the widths of the inner bus bars and consequent increase in resistive losses are offset by several connections to a further bus 23, 43 via groups 25 of dummy electrodes arranged at null points in the weighting pattern.

Abstract: An acoustic surface wave device employing an input and an output transducer (2, 3) and a multistrip coupler (5). The input and output tracks (11, 12) are separated to avoid unwanted acoustic energy transfer. As a result, a significant loss can occur from the launching of acoustic energy from the interconnecting conductors of the msc. The interconnecting conductors (22, 32') of the multistrip coupler are spaced differently from the, or the equivalent, wide-aperture beam spacing of conductors (16, 17; 36', 37') in either track of the msc so as not to launch any acoustic surface or bulk waves within the frequency passband. In a forward transfer msc different spacings can alternate, and in a reflective msc the spacing can take the mean of the respective equivalent wide-aperture-beam spacings of the coupler electrodes.