Abstract: A method for operating an MR system with a gradient pulse amplifier unit that has an end stage connected to a gradient coil with switching elements is provided. The gradient pulse amplifier unit includes a modulator for actuating the switching elements, and lockout switches interconnected in signal paths from the modulator to the switching elements. The gradient pulse amplifier unit includes feeder circuit breakers interconnected in at least some signal paths from the modulator to the switching elements. The circuit breakers are connected in the associated signal paths downstream of the lockout switches. A gradstop unit configured to receive at least one shut-off signal and actuate the lockout switches and the feeder circuit breakers. When the gradstop unit receives a shut-off signal, the gradstop unit actuates the lockout switches to lock out and the feeder circuit breakers to output an actuation signal to the switching elements.

Abstract: A magnetic resonance apparatus with a safety structure for monitoring a safety-related function is provided. The safety structure includes a control path that is configured to control the safety-related function, and a first protect path and a second protect path. The first protect path and the second protect path are configured to acquire a safety-related parameter of the safety-related function. The first protect path is configured to identify a hazardous situation, independently of the control path and the second protect path, based on the safety-related parameter that the first protect path acquires. The second protect path is configured to identify a hazardous situation, independently of the control path and the first protect path, based on the safety-related parameter that the second protect path acquires. The first protect path and the second protect path are each configured to transfer the magnetic resonance apparatus into a safe state in a hazardous situation.

Abstract: A method for operating an MR system with a gradient power amplifier having at least one output stage that is connectable to a gradient coil, and having four switching elements connected to one another as an H-bridge includes, to operate the gradient coil, in alternation: switching the switching elements attached to a common first pole of a voltage supply to conductive and switching the switching elements attached to a common second pole of a voltage supply to blocking by inverting power drivers; and switching the switching elements attached to a common first pole of a voltage supply to blocking and switching the switching elements attached to a common second pole of a voltage supply to conductive by inverting power drivers. The switching elements attached to the first pole are switched by non-inverting power drivers, and the switching elements attached to the second pole are switched by inverting power drivers.

Abstract: A method for operating an MR system with a gradient pulse amplifier unit that has an end stage connected to a gradient coil with switching elements is provided. The gradient pulse amplifier unit includes a modulator for actuating the switching elements, and lockout switches interconnected in signal paths from the modulator to the switching elements. The gradient pulse amplifier unit includes feeder circuit breakers interconnected in at least some signal paths from the modulator to the switching elements. The circuit breakers are connected in the associated signal paths downstream of the lockout switches. A gradstop unit configured to receive at least one shut-off signal and actuate the lockout switches and the feeder circuit breakers. When the gradstop unit receives a shut-off signal, the gradstop unit actuates the lockout switches to lock out and the feeder circuit breakers to output an actuation signal to the switching elements.

Abstract: A method for operating an MR system with a gradient power amplifier having at least one output stage that is connectable to a gradient coil, and having four switching elements connected to one another as an H-bridge includes, to operate the gradient coil, in alternation: switching the switching elements attached to a common first pole of a voltage supply to conductive and switching the switching elements attached to a common second pole of a voltage supply to blocking by inverting power drivers; and switching the switching elements attached to a common first pole of a voltage supply to blocking and switching the switching elements attached to a common second pole of a voltage supply to conductive by inverting power drivers. The switching elements attached to the first pole are switched by non-inverting power drivers, and the switching elements attached to the second pole are switched by inverting power drivers.

Abstract: A method for actuating a gradient coil can include the provision of a target value for a manipulated variable, the output of the manipulated variable according to the target value to the gradient coil, the capture of an actual value of the output manipulated variable, the scaling of the captured actual value taking into consideration a scaling characteristic depending on the target value, and the transformation of the actual value captured in a scaled manner into a digital actual value.

Abstract: A magnetic resonance apparatus with a safety structure for monitoring a safety-related function is provided. The safety structure includes a control path that is configured to control the safety-related function, and a first protect path and a second protect path. The first protect path and the second protect path are configured to acquire a safety-related parameter of the safety-related function. The first protect path is configured to identify a hazardous situation, independently of the control path and the second protect path, based on the safety-related parameter that the first protect path acquires. The second protect path is configured to identify a hazardous situation, independently of the control path and the first protect path, based on the safety-related parameter that the second protect path acquires. The first protect path and the second protect path are each configured to transfer the magnetic resonance apparatus into a safe state in a hazardous situation.

Abstract: A method for actuating a gradient coil can include the provision of a target value for a manipulated variable, the output of the manipulated variable according to the target value to the gradient coil, the capture of an actual value of the output manipulated variable, the scaling of the captured actual value taking into consideration a scaling characteristic depending on the target value, and the transformation of the actual value captured in a scaled manner into a digital actual value.

Abstract: A method for monitoring a temporal change in a magnetic field in a magnetic resonance device, as well as an evaluation unit, a magnetic resonance device, and a computer program product for performing the method are provided. The method provides that a position-dependent magnetic field distribution that is produced by the plurality of gradient coils is provided with a plurality of monitoring points. In addition, time-dependent gradient values of the plurality of gradient coils are ascertained. Based on position-dependent magnetic field distribution and the time-dependent gradient values, the temporal change in the magnetic field is ascertained. The temporal change in the magnetic field is monitored by comparing the temporal change in the magnetic field with at least one limit value.

Abstract: Systems and methods are provided for determining a use of a system component in an imaging system. The imaging system includes a primary side configured to provide power to the system component and a secondary side including the system component that uses the power provided by the primary side during the image sequence. The method includes determining the use of the system component during an imaging sequence, determining a time averaged power provided by the primary side during the imaging sequence, determining a maximum time averaged power that may be provided by the primary side until a temperature limit is reached on the primary side. Further, whether the time averaged power is smaller than the maximum time averaged power is determined.

Abstract: The invention relates to the use of a hybrid material comprising a) an organopolysilazane material and b) at least one surface-modified nanoscale inorganic oxide as coating material for producing transparent layers having a thickness of less than 500 ?m in optoelectronic components.

Abstract: A circuit arrangement for an MRT system and a method for operating an MRT system are disclosed. The circuit arrangement includes a gradient amplifier having a switch-mode output stage, a regulator device, and a modulator connected therebetween in the circuit. To ensure patient safety, a control path is integrated into a drive path of the circuit arrangement or the MRT system provided for driving a gradient coil, the gradient coil being connected to an output of the switch-mode output stage. The control path includes a limiter stage connected downstream of the regulator device, the modulator, the switch-mode output stage and its supply voltage. The limiter stage is connected in the circuit between the regulator device and an input of the modulator, to limit a control signal output by the regulator device and limit the voltage for the gradient coil provided by the switch-mode output stage at its output.

Abstract: A circuit arrangement for an MRT system and a method for operating an MRT system are disclosed. The circuit arrangement includes a gradient amplifier having a switch-mode output stage, a regulator device, and a modulator connected therebetween in the circuit. To ensure patient safety, a control path is integrated into a drive path of the circuit arrangement or the MRT system provided for driving a gradient coil, the gradient coil being connected to an output of the switch-mode output stage. The control path includes a limiter stage connected downstream of the regulator device, the modulator, the switch-mode output stage and its supply voltage. The limiter stage is connected in the circuit between the regulator device and an input of the modulator, to limit a control signal output by the regulator device and limit the voltage for the gradient coil provided by the switch-mode output stage at its output.

Abstract: A hybrid material for light emitting diodes, comprising a) an organopolysilazane material, comprising repeating units of formulae (I) and (II) [—SiR1R2—NR3—]x??(I) [—SiHR4—NR5—]y??(II) wherein the symbols and indices have the following meanings: R1 is C2-C6-alkenyl or C4-C6-alkadienyl; R2 is H or an organic group; R3 is H or an organic group; R4 is H or an organic group; R5 is H or an organic group; x is 0.001 to 0.2; and y is 2x to (1?x), with the proviso that x+y?1 and that y can be 0 if R2 is H, and b) inorganic nanoparticles having a mean diameter in the range of from 1 to 30 nm, which are surface modified with a capping agent comprising a C1-C18-alkyl and/or C1-C18-alkenyl group, is useful as encapsulation material for LEDs.

Abstract: The invention relates to the use of specific organopolysilazanes as an encapsulation material for light emitting diodes (LED). The organopolysilazane polymers act as insulating filling materials and are stable over temperature and over exposure to ambient UV radiation. The encapsulating material has good thermal stability against discoloration to yellow by aging even at high temperatures which is a key factor for the long lifetime of an LED encapsulant and the LED performance.

Abstract: A method for monitoring a temporal change in a magnetic field in a magnetic resonance device, as well as an evaluation unit, a magnetic resonance device, and a computer program product for performing the method are provided. The method provides that a position-dependent magnetic field distribution that is produced by the plurality of gradient coils is provided with a plurality of monitoring points. In addition, time-dependent gradient values of the plurality of gradient coils are ascertained. Based on position-dependent magnetic field distribution and the time-dependent gradient values, the temporal change in the magnetic field is ascertained. The temporal change in the magnetic field is monitored by comparing the temporal change in the magnetic field with at least one limit value.

Abstract: A circuit arrangement for generating a current for an inductive load is provided. The circuit includes a switched output state, a modulator, a current measuring device, a controller, a compensator, and a summer. The switched output stage is configured to generate the current from a supply voltage. The modulator is configured to modulate the supply voltage of the output stage depending on a modulator input signal of the modulator. The current measuring device is configured to determine the actual value of the current. The controller is configured to generate a controller signal depending on a setpoint value of the current and the actual value of the current. The compensator is configured to generate from the setpoint value of the current at least one compensation control signal that compensates for nonlinearities of the output stage. The summer is configured to generate the modulator input signal additively from the controller signal and the at least one compensation control signal.

Abstract: A circuit arrangement for generating a current for an inductive load is provided. The circuit includes a switched output state, a modulator, a current measuring device, a controller, a compensator, and a summer The switched output stage is configured to generate the current from a supply voltage. The modulator is configured to modulate the supply voltage of the output stage depending on a modulator input signal of the modulator. The current measuring device is configured to determine the actual value of the current. The controller is configured to generate a controller signal depending on a setpoint value of the current and the actual value of the current. The compensator is configured to generate from the setpoint value of the current at least one compensation control signal that compensates for nonlinearities of the output stage. The summer is configured to generate the modulator input signal additively from the controller signal and the at least one compensation control signal.

Abstract: The invention relates to the use of a hybrid material comprising a) an organopolysilazane material and b) at least one surface-modified nanoscale inorganic oxide as coating material for producing transparent layers having a thickness of less than 500 ?m in optoelectronic components.

Abstract: This invention relates to a composition of a non-labeled monoclonal antibody binding to a tumor antigen and a second monoclonal antibody labeled with a NIR fluorescence label, binding to the same tumor antigen, wherein the first and second antibody exhibit no cross reactivity. The composition can be used for the treatment of patients suffering of solid tumors which are associated with an overexpression of such a tumor antigen. The invention further relates to a the co-administration of said first and second antibody as wells as to a method of acquiring a NIR fluorescence images of such tumors or the patients suffering from such tumors during the treatment of said patient with such composition.