Abstract: The invention relates to organisms and compositions comprising one or more stem cells or one or more embryos, wherein the one or more stem cells or one or more embryos comprise one or more of the following mutations: (i) a deletion mutation; (ii) a knockout mutation; and/or (iii) an addition of a heterologous nucleic acid sequence; wherein the one or more mutations of (i), (ii), and/or (iii) are site-specific mutations caused by a Xanthomonas TAL nuclease (XTN). The invention also relates to method of mutating an embryo, iPS cell, stem cell, or more particularly a spermatogonial stem cell by exposing the nucleic acid sequence contained within such embryos or cell with a Xanthomonas TAL nuclease.

Abstract: The temperature of a heating element (3), which heating element has a temperature dependent resistance, is measured by comparing the current through it with a user adjustable reference value. The AC voltage across a current sensing resistor (7) in series with the heating element (3) is compared in a comparator (9) with a reference AC voltage generated at a tap (6) of a voltage divider (8). The phase of the logic output signal of the comparator (9) indicates a first state in which the heating element (3) is too hot or is not conducting, or a second state in which the heating element (3) is too cold and conducting. A second comparator (16) detects whether or not the heating element (3) is conducting. A logic gate (18) and a latch (17) switch on the current through the heating element (3) in response to timed pulses from a timing circuit (15) and switch off the current through the heating element (3) when the heating element (3) is conducting and too hot.

Abstract: A trigger control circuit of the kind wherein a load is supplied via a triac with current from an AC voltage supply source under the control of a triac control means in combination with a sensing element. In previous circuits the sensing element is energized by a current from a DC source which is derived by rectification and smoothing of the alternating current of an alternating voltage supply source. These circuits have limitations in integrated circuitry. The sensing element herein is energized by an alternating current to produce a sensed alternating current. The triac control means includes an integration element for producing a control signal which represents of the integral of the difference between a value corresponding to the magnitude of the sensed alternating current and a reference value. The triggering or otherwise of the triac is determined by a latch actuated in response to the magnitude of the control signal relative to one or more threshold levels.

Abstract: Circuit arrangements for use in the generation of sparks for igniting gas at a gas burner assembly whereby the operation is controlled electrically by means of an electronic control circuit which reacts to the presence or absence of a gas flame. The circuit comprises a charging circuit for a charge storage capacitor, a spark output transformer, an SCR switching device for discharging the charge stored in the capacitor and a non-linear conductive element connected between the anode and the gate of the SCR. Therefore when the anode voltage reaches the required value a trigger signal is applied via said non-linear conductive element to the gate to trigger the discharge of the capacitor by the SCR.

Abstract: Circuit arrangements to improve the performance of motor speed control circuits using electronic switching on an AC waveform where it is desired to remotely control the electronic switch without either load current or the load waveforms being present at the controlling element. The voltage across the switching device, during the time it is off, is rectified, and used as the charging voltage for the phase firing circuit, with a resistor capacitor timing network determining the firing of the switching device when the capacitor voltage reaches a predetermined value.

Abstract: The invention provides a probe set for use particularly in the canaliculus intubation of the lacrimal duct, the probe set comprising: a probe of a light wire which can be readily deflected through an angle of at least 90 degrees to permit the probe to pass from the nasolacrimal duct to the inferior meatus, the probe having an enlarged end portion which is rounded to limit the possibility of damage to tissue when the probe is inserted; and a very flexible tube of minimal rigidity having a first end attached to an end of the probe remote from the end portion and having an outside diameter comparable to that of the end portion so that in use the probe can be inserted and used to draw the tube into the lacrimal duct.