voltage

Overvoltage limiter in an aircraft electrical power generation system

A generator includes a permanent magnet generator, an exciter and a main generator mounted for rotation on a shaft. The main generator is configured to produce a voltage output. A generator control unit includes a circuit configured to provide current from the permanent magnet generator to the exciter. A switch is provided in the circuit and is configured to change between open and closed conditions. The switch is configured to flow current in the circuit in the closed condition and interrupt current flow in the open condition. An overvoltage limit controller is programmed to determine an amount of overvoltage of the output voltage exceeding a desired voltage. Either a fixed reference threshold is used or a reference threshold voltage is calculated based upon the duration in over voltage condition, and the switch is modulated between the open and closed conditions according to error between the actual output voltage and the reference threshold voltage to limit the output voltage to the desired reference threshold voltage.




voltage

Power supply system for motor vehicle provided with control device of voltage applied to field coil of generator

A power supply system for a motor vehicle includes a generator that includes a rotor having a field coil and a stator having an armature coil; a rectifier that rectifies AC power generated in the armature coil; an excitation control circuit that takes control of a voltage applied to the field coil; a capacitor that is connected to the DC side of the rectifier, and receives and transfers the rectified power; a battery connected to an electric load of the motor vehicle; a DC-DC converter that is connected between the capacitor and the battery and capable of converting unidirectionally or bidirectionally an input DC voltage into any DC voltage; and a selection switch which connects the capacitor or the battery to the excitation control circuit as a power supply source.




voltage

DC voltage converter and shock-type high voltage utilization devices

A DC voltage converter includes an oscillator that converts a DC battery voltage to an oscillating voltage, a low voltage transformer that increases the oscillating voltage to a higher oscillating voltage, and a voltage rectifying-capacitor charging network or multiplier that increases the higher oscillating voltage to yet a higher DC voltage at an output terminal for DC high voltage utilization devices and the like. An electric control switch is selectively actuated by the user to apply the battery voltage to the oscillator, resulting in the generation of the stepped-up DC voltage at an output terminal. Another DC voltage converter has an electronic switching circuit that automatically turns the oscillator on and off and a load capacitor across the electrodes that is charged and discharged to provide a shocking voltage. Utilization devices for the voltage developed by the converter shown are a miniature animal training device and a cattle prod device. The miniature animal training device has a pair of outwardly projecting electrodes mounted on a side at one end of the housing that is sized and shaped to fit within and conform to the palm of a hand. The cattle prod device has a pair of electrodes fixedly mounted on the end of a housing assembly made up of telescoping tubular housing sections arranged for relative axial movement whereby the pressing of the electrodes against an object to be shocked actuates the electric control switch and causes a shock of the object. The housing assembly is releasably supported by a rigid handle or an extensible handle assembly.




voltage

Methods and apparatus for applying periodic voltage using direct current

Methods and apparatus for applying pulsed DC power to a plasma processing chamber are disclosed. In some implementations, frequency of the applied power is varied to achieve desired processing effects such as deposition rate, arc rate, and film characteristics. In addition, a method and apparatus are disclosed that utilize a relatively high potential during a reverse-potential portion of a particular cycle to mitigate possible nodule formation on the target. The relative durations of the reverse-potential portion, a sputtering portion, and a recovery portion of the cycle are adjustable to effectuate desired processing effects.




voltage

A/D converter and solid-state imaging apparatus with offset voltage correction

Provided is an A/D converter including an input terminal, a reference signal line for supplying a reference signal which changes temporally, a comparator, a correction capacitor connected to an inverting input terminal of the comparator; and an output circuit which outputs digital data corresponding to an analog signal input to the input terminal. In a first state in which a total voltage of a first analog signal and an offset voltage of the comparator is held in the correction capacitor, a second analog signal input to the input terminal is supplied to a non-inverting input terminal of the comparator, and the second analog signal or the total voltage is changed using the reference signal, thereby outputting, from the output circuit, digital data.




voltage

Image sensors having variable voltage-current characteristics and methods of operating the same

Image sensors and methods of operating the same. An image sensor includes a pixel array including a plurality of pixels. Each of the plurality of pixels includes a photo sensor, the voltage-current characteristics of which vary according to energy of incident light, and that generates a sense current determined by the energy of the incident light; a reset unit that is activated to generate a reference current, according to a reset signal for resetting at least one of the plurality of pixels; and a conversion unit that converts the sense current and the reference current into a sense voltage and a reference voltage, respectively.




voltage

Dielectric loaded fluids for high voltage switching

This disclosure relates to methods and systems to reduce high voltage breakdown jitters in liquid dielectric switches. In particular, dielectric liquids have been produced that contain a suspension of nanoparticles and a surfactant to reduce the breakdown jitter. In one embodiment, the suspended nanoparticles are Barium Strontium Titanate (BST) nanoparticles.




voltage

Medium-voltage switchgear assembly

The invention relates to a medium voltage switchgear assembly which comprises at least one disconnector and whose drive unit is disposed inside or outside a gas chamber according to the generic part of claim 1. In order to further develop a switchgear assembly of the generic type so as to render the same more compact and more functional, the disconnector is embodied as a three-position vacuum chamber switch.




voltage

Medium and high-voltage electric switch with return on closure and an insertion device for inserting a resistance

An electric switch for application to high- and very high-voltage circuit breakers and switches comprising a flexible toroidal helical spring (8) placed in a groove of a control rod (1) carrying a movable resistance-insertion contact (2), and springs (4) placed about the movable resistance-insertion contact to cause the springs to be compressed until a certain value is reached, at which value the movable resistance-insertion contact causes the flexible toroidal helical spring (8) to deform under pressure enabling the movable resistance-insertion contact (2) to be withdrawn. Among other uses, the switch is suitable for use in a resistance-inserting device that does not need additional mechanical moving parts. For application to high- and very high-voltage circuit breakers and switches.




voltage

Sealed solenoid magnetically operated high voltage electric power switch

A sealed solenoid, magnetically operated electric power switch is suitable for use as capacitor, line and load switch operating at transmission and distribution voltages that includes no dynamically moving seals through the sealed container housing the contactor portion of the switch. The sealed solenoid switch includes a magnetically operated drive system with an actuator that magnetically couples across the container wall to avoid the use of a moving or sliding seal as part of the drive system. The sealed solenoid switch may also include a ballast resistor and resistor contact located inside the sealed container to avoid another seal as part of the ballast system. A magnetic latch holds the switch in a closed position, and a spring holds the switch in the closed position, to avoid the need for an energizing current to maintain the switch in either position.




voltage

High voltage relay non mercury

The high voltage relay consists of a main body (1). One set of electrical contacts (2a, 2b) upper and lower respectively. High voltage connections to connect the voltage being switched (3a, 3b) are electrically connected to the upper and lower contacts respectively. Several size options for the electrical contacts will allow for a wide range of currents. A cylinder (4) driven by a fluid (e.g. Air, Nitrogen, Hydraulic fluid) moves the electrical contacts together during the ON state of the device. During the OFF state of the device the cylinder moves the electrical contacts apart to isolate the switch voltage. The greater the High Voltage being switched the greater the distance the electrical contacts must be moved apart in the OFF state. The cylinder is supplied the fluid power from a small solenoid (5) on the device. This solenoid has control voltage connections to actuate the device.




voltage

Variable switched DC-to-DC voltage converter

A voltage converter can be switched among two or more modes to produce an output voltage tracking a reference voltage that can be of an intermediate level between discrete levels corresponding to the modes. One or more voltages generated from a power supply voltage, such as a battery voltage, can be compared with the reference voltage to determine whether to adjust the mode. The reference voltage can be independent of the power supply voltage.




voltage

Line voltage control circuit for a multi-string LED drive system

A line voltage control circuit for use with a multi-string LED drive system which provides a common line voltage for multiple LED strings that are connected to respective current sink circuits at respective junctions. An error amplifier receives the minimum junction voltage and a reference ‘desired junction voltage’ at respective inputs, and a voltage regulator outputs the line voltage in response to a voltage applied to a feedback input. A comparator toggles an output when the maximum junction voltage (Vmax) exceeds a reference limit (Vlimit). A multiplexer receives the error amplifier output and a fixed voltage at respective inputs and provides one of the signals to the regulator's feedback input in response to the comparator output. When Vmax>Vlimit, the fixed voltage is provided to the feedback input and the line voltage is reduced, thereby protecting low voltage current sinks from potentially damaging high voltages.




voltage

Voltage-to-current sensing circuit and related DC-DC converter

The present disclosure is directed to a voltage-to-current sensing circuit having a bias terminal configured to receive a reference voltage, an offset terminal configured to receive an offset current, and an operational amplifier configured to output a low voltage signal. The device includes a first amplifier having first and second high voltage inputs configured to receive a first voltage difference across a sense component on a high voltage line and to generate a first current, a second amplifier having first and second low voltage inputs configured to receive a second voltage difference between the bias terminal and the offset terminal and to generate a second current, a summing circuit configured to provide an intermediate voltage corresponding to a sum of the first and the second currents, and a low-voltage transistor coupled to an output of the amplifier and controlled by the intermediate voltage to generate the output current.




voltage

System and method for multi-phase voltage regulation

In accordance with one embodiment of the present disclosure, a multi-phase voltage regulator may comprise a plurality of phases, each phase configured to supply electrical current to one or more information handling resources electrically coupled to the voltage regulator. A controller may be electrically coupled to the plurality of phases. The controller may designate at least one of the plurality of phases as a first state phase, and designate each of the plurality of phases not designated as a first state phase as a second state phase. The controller may alternate the designation of at least two of the plurality of phases between a first state phase and a second state phase. Each first state phase may be configured to supply a first electrical current regardless of electrical current demand. Each second state phase may be configured to supply a second electrical current based on the current demand.




voltage

Voltage regulator with current limiter

A voltage regulator includes an amplifier having a first input coupled to a first reference voltage and a second input coupled to a voltage feedback signal; a multiplexer having a first input coupled to an output of the amplifier, a second input coupled to a voltage clamp signal, and a control input; and a control circuit having a first input coupled to an over current indicator, a second input coupled to a no over voltage indicator, a third input coupled to a timer signal, and an output coupled to the control input of the multiplexer.




voltage

Charge pump regulator circuit with a variable drive voltage ring oscillator

A charge pump regulator circuit includes a voltage controlled oscillator and a plurality of charge pumps. The voltage controlled oscillator has a plurality of inverter stages connected in series in a ring. A plurality of oscillating signals is generated from outputs of the inverter stages. Each oscillating signal has a frequency or amplitude or both that are variable dependent on a variable drive voltage. Each oscillating signal is phase shifted from a preceding oscillating signal. Each charge pump is connected to a corresponding one of the inverter stages to receive the oscillating signal produced by that inverter stage. Each charge pump outputs a voltage and current. The output of each charge pump is phase shifted from the outputs of other charge pumps. A combination of the currents thus produced is provided at about a voltage level to the load.




voltage

Wide output voltage range switching power converter

A switching power converter includes a voltage source that provides an input voltage Vin to an unregulated DC/DC converter stage and at least one buck-boost converter stage to produce a desired output voltage Vout. The unregulated DC/DC converter stage is adapted to provide an isolated voltage to the at least one regulated buck-boost converter stage, wherein the unregulated DC/DC converter stage comprises a transformer having a primary winding and at least one secondary winding and at least one switching element coupled to the primary winding. The at least one buck-boost converter stage is arranged to operate in a buck mode, boost mode or buck-boost mode in response to a mode selection signal from a mode selection module. By influencing the pulse width modulation output power controller the at least one buck-boost converter stage is arranged to produce one or multiple output voltages.




voltage

Reference voltage circuit and image-capture circuit

A reference voltage circuit for generating a reference voltage to be referred when a pixel signal is digitally converted, includes ramp voltage generating means for generating a ramp voltage which drops from a predetermined initial voltage at a certain gradient, a transistor for forming, together with the ramp voltage generating means, a current mirror circuit, and gain change means for changing a current value of a current flowing from a predetermined power supply via the transistor to change the gradient of the ramp voltage generated by the ramp voltage generating means.




voltage

Low-dropout voltage regulator

A low-dropout voltage regulator includes a power transistor configured to receive an input voltage and to provide a regulated output voltage at an output voltage node. The power transistor includes a control electrode configured to receive a driver signal. A reference circuit is configured to generate a reference voltage. A feedback network is coupled to the power transistor and is configured to provide a first feedback signal and a second feedback signal. The first feedback signal represents the output voltage and the second feedback signal represents an output voltage gradient. An error amplifier is configured to receive the reference voltage and the first feedback signal representing the output voltage. The error amplifier is configured to generate the driver signal dependent on the reference voltage and the first feedback signal. The error amplifier includes an output stage that is biased with a bias current responsive to the second feedback signal.




voltage

Railroad signaling and communication system using a fail-safe voltage sensor to verify trackside conditions in safety-critical railroad applications

A method and system for verifying trackside conditions in safety critical railroad applications by reporting the status of trackside signals and switches to a remote train control system. The system comprises at least one sensor for providing trackside conditions electrically connected to a circuit for providing trackside conditions to a railroad, said sensor being powered by voltage applied to the circuit such that the sensor is energized only when said electrical component is engaged. The system and method further comprises a method and system which is failsafe and which enables the control system to independently verify signals from each sensor.




voltage

Protective device and method for preventing supply voltage sag of microcontroller from sagin electronic cigarette

A protective device and method for preventing supply voltage of microcontroller from sag in electronic cigarette is provided, comprising a microcontroller, a power supply module, a field effect transistor, an energy storage circuit, wherein, the energy storage circuit is connected between the microcontroller and the power supply module, the energy storage circuit supplies electric power to the microcontroller when an over current or short circuit occurs, and maintains the supply voltage of the microcontroller not being less than its minimal operating voltage in a certain period of time; the microcontroller processes the over current or short circuit signal and turns off the MOSFET to cut off the current flow in a load circuit. The unstable or uncontrollable phenomena of the microcontroller in the existing technology are resolved. The circuit of the present invention is simple and low cost.




voltage

VOLTAGE REGULATION CIRCUIT

A voltage regulation circuit is provided, including a reverse processing module for processing a first initial voltage of a common voltage generating module so as to obtain a reverse voltage of AC voltage; and an integration module for regulating the first initial voltage according to the reverse voltage of the AC voltage so as to make a liquid crystal drive voltage equal to a preset value. The liquid crystal drive voltage is a difference value of between a second initial voltage and the first initial voltage which is regulated.




voltage

SYSTEM AND METHOD FOR CONTROLLING A VOLTAGE CONTROLLED OSCILLATOR

An electrical circuit includes: at least one inductor, at least one varactor, and at least two transistors, all of which electrically arranged to form a voltage controlled oscillator (VCO) having an oscillation frequency; wherein the at least two transistors includes a first transistor and a second transistor; wherein the first transistor has a first bulk terminal and a first parasitic diode disposed between the first bulk terminal and the first transistor; wherein the second transistor has a second bulk terminal and a second parasitic diode disposed between the second bulk terminal and the second transistor; wherein application of a first control voltage to the first bulk terminal, application of a second control voltage to the second bulk terminal, or application of first and second control voltages to the first and second bulk terminals, respectively, is effective to change the oscillation frequency of the VCO.




voltage

Voltage-Resistant Switch

A voltage-resistant switch is described. The switch comprises a signal input, a first FET transistor with a first channel with an extended drain and a first gate connector and a second FET transistor with a first channel with an extended drain and a second gate connector. A control signal connector is connected with the first gate connector and with the second gate connector via a second node and with the first channel and the second channel via a second resistor, and a signal connector is connected with the second channel. The voltage-resistant switch can be switched on and off.




voltage

LOOP FILTER WITH ACTIVE DISCRETE-LEVEL LOOP FILTER CAPACITOR IN A VOLTAGE CONTROLLED OSCILLATOR

A loop filter with an active discrete-level loop filter capacitor can be used in a VCO (such as for CDR). A loop filter capacitor function is simulated by sensing input loop filter current (such as with a current mirror and source follower in the input leg), and forcing back a loop filter (VCO) control voltage. Loop filter voltage control is provided using a VDAC with a discrete-level VDAC feedback voltage, incremented/decremented based on the sensed loop filter current. In one embodiment, the VDAC voltage is provided as the non-inverting input to an amplifier, with the inverting input providing the control voltage, forced to the VDAC feedback voltage. The VDAC feedback voltage can be provided by increment/decrement comparators based on a voltage deviation on a C2 capacitor (from a reference voltage) that receives the sensed loop filter current (effectively multiplying the C2 capacitance to provide a simulated loop filter capacitance).




voltage

LOW INERTIA POWER SUPPLY FOR APPLYING VOLTAGE TO AN ELECTRODE COUPLED TO A FLAME

A system and method for electrically charging a combustion flame with a power supply.




voltage

SUBSEA HIGH VOLTAGE CONNECTION ASSEMBLY

Subsea high voltage connection assembly (10) comprising a first section (100) having a first section body (104) to which a set of first connector(s) (111) is arranged and a second section (200) having second section body (204) to which a set of second connector(s) (211) is arranged. The assembly (10) further has a section body movement arrangement (103, 400, 9, 123) adapted to move one of the section bodies (104, 204) towards and away from the other section body, between a disengaged position and an engaged position. Further, the assembly (10) has a connector movement arrangement (105, 400). Also disclosed are a method and a subsea high voltage wet mate connector assembly.




voltage

DEVICE FOR COOLING HOT GASES IN A HIGH-VOLTAGE EQUIPMENT

The invention relates to a device for cooling hot gases generated by an internal arc in high voltage metal-enclosed switchgear and controlgear or prefabricated high voltage/low voltage stations. This device comprises a metal foam cooling filter having a honeycomb structure.




voltage

DIGITAL-TO-ANALOG CONVERTER AND HIGH-VOLTAGE TOLERANCE CIRCUIT

A digital-to-analog converter (DAC) and a high-voltage tolerance circuit are provided. The DAC includes a high-voltage tolerance circuit. The high-voltage tolerance circuit is configured to generate a reference voltage, and select the reference voltage or a first power-source voltage to control the node voltage of each branch of an operational amplifier circuit of the high-voltage tolerance circuit according the logical signal level of an input signal.




voltage

Circuit for Stabilizing a Digital-to-Analog Converter Reference Voltage

The disclosure relates to a circuit for stabilizing a digital-to-analog converter reference voltage. One example embodiment is a circuit for stabilizing a voltage on a reference node. The circuit includes a digital-to-analog converter that includes an array of capacitors and arranged for: receiving an input voltage via an input node, receiving a voltage via a reference node and a digital-to-analog code via a controller node, and outputting a digital-to-analog output voltage. The circuit also includes a capacitive network on the reference node comprising a fixed capacitor arranged to be pre-charged to an external reference voltage and a variable capacitor arranged to be pre-charged to an external auxiliary voltage. Further, the circuit includes a measurement block. In addition, the circuit includes a calibration block arranged for determining an updated setting of the variable capacitor based on the digital-to-analog code and the measured voltage on the reference node.




voltage

PIEZOELECTRIC DEVICE FOR GENERATING ELECTRICAL VOLTAGE

An electrical voltage-generating piezoelectric device comprising at least a first blade (1) with a curved portion (10) defining a first arm (11) and a second arm (12) of the blade, the first arm (11) being intended to be fastened to a fixed support, the second arm (12) being substantially flat and having a free end (120) designed to oscillate around its resting position under the effect of mechanical force, at least one piezoelectric element (31) resting upon one of the main surfaces (14) of the second arm (12) of the first blade. The device also includes a second blade (2) identical in structure to the first blade (1), the first arms (11, 21) of the first and second blades (1, 2) being fastened together on all or part of their surfaces and being fixed relative to each other.




voltage

SYSTEM AND FABRICATION METHOD OF PIEZOELECTRIC STACK THAT REDUCES DRIVING VOLTAGE AND CLAMPING EFFECT

A system and method provides a piezoelectric stack arrangement for reduced driving voltage while maintaining a driving level for active piezoelectric materials. A stack arrangement of d36 shear mode single crystals of both air X-cut and Y-cut ±1:45° (±20°) arrangement are bonded with discrete conductive pillars to form a shear crystal stack. The bonding area between the neighboring crystal parts is minimized. The bonding pillars are positioned at less than a total surface are of the single crystal forming the stack. The stack fabrication is facilitated with a precision assembly system, where crystal parts are placed to desired locations on an assembly fixture for alignment following the preset operation steps. With the reduced clamping effect from bonding due to lower surface coverage of the discrete conductive pillars, such a piezoelectric d36 shear crystal stack exhibits a reduced driving voltage while maintaining a driving level and substantial and surprisingly improved performance.




voltage

HIGH-VOLTAGE DRY APPARATUS PROVIDED WITH A CONTINUOUS MONITORING DEVICE

The invention relates to a high-voltage dry apparatus having a semiconductor layer (2) covered by a metal screen (3), this screen (3) being eliminated so as to expose this semiconductor layer (2) over a length, this cable being connected to an element of equipment having an outer envelope (6) mechanically connected to said screen. According to the invention, an electronic monitoring arrangement (20) is contained within said envelope (6), this electronic arrangement (20) being electrically connected to an electrical power supply arrangement (21) surrounding said semiconductor layer (2) and to the metal screen (3) of said cable on either side of said length of the exposed semiconductor layer.




voltage

POWER SYSTEM FOR SUPPLYING HIGH VOLTAGE TO AN ELECTRON BEAM EMITTER

Power system for supplying high voltage to an electron beam emitter, which is adapted to sterilize a packaging container or a packaging material by electron beam irradiation, the power system comprising a voltage multiplier for generating a high voltage, a first voltage measurement device for measuring an output voltage level of the voltage multiplier and providing a first measured voltage value, and an actuator for modifying the output voltage level of the voltage multiplier based on the first measured voltage value provided by the first voltage measurement device, characterized in that the power system further comprises a second voltage measurement device adapted to independently measure the output voltage level of the voltage multiplier and provide a second measured voltage value.




voltage

DEVICE FOR THERMALLY TRIPPING OR DISCONNECTING AN OVERVOLTAGE PROTECTION DEVICE

The invention relates to a device for thermally disconnecting or tripping an overvoltage protection device, comprising: a locking element (A1), on which a first force (F1) acts, and which is fixed in such a way that same is released when a limit temperature is exceeded; and a slider (S1) which is blocked in a first state (Z1) by the fixed locking element (A1), and on which a second force (F2) acts in order to transfer same into a second state (Z2) when the locking element (A1) is released.




voltage

OVERVOLTAGE PROTECTION DEVICE

An overvoltage protection device includes a resistor that is connected in series between an internal signal line connected to a communication terminal of a processor and a communication line, a diode of which a cathode is connected to the internal signal line and an anode is connected to a ground, and a PNP transistor of which a base is connected to a power supply terminal, an emitter is connected to the internal signal line, and a collector is connected to the ground. When a base-emitter voltage (a junction saturation voltage) of the transistor in operation is defined as VBE and a power source is turned on (a voltage V1) by the operation of the transistor, a voltage of the internal signal line is limited to the source voltage V1+VBE. When the power source is turned off (a voltage 0 V), the voltage of the internal signal line is limited to the source voltage 0 V+VBE.




voltage

ELECTRICAL ENERGY RECEIVING END CAPABLE OF OVERVOLTAGE PROTECTION AND WIRELESS ELECTRICAL ENERGY TRANSMISSION DEVICE

An electrical energy receiving end capable of overvoltage protection and a wireless electrical energy transmission device are provided. An electrical energy receiving coil is divided into a first receiving coil and a second receiving coil, so that under normal operation the first receiving coil and the second receiving coil jointly resonate with an impedance matching network to receive energy. When the electrical energy receiving end has an overvoltage, the first receiving coil and the impedance matching network (or the second receiving coil and the impedance matching network) form a loop, and due to the impedance mismatch, the energy received by the electrical energy receiving end is greatly reduced to solve the problem of overvoltage at the electrical energy receiving end.




voltage

Buddha Machine Variations No. 23 (Voltage Redress)

The batteries were dying on one of the Buddha Machines, so I recharged them. But only a bit. Just enough to let them last for this recording. The green one on the left is the one giving out the dying-whale sounds, the dying Buddha. The blue one is fully charged. Both are sending loops of […]




voltage

High Voltage Development Engineer

Roles & Responsibilities Document test methods, perform system testing, and document test results for HV system performance testing Lab development testing and documentation of power electronic subsystems Testing of high voltage, high power electronic components including system bring up an




voltage

High Voltage Design Engineer

Roles & Responsibilities: Design and optimization of HV circuits (450 to 1700 V) including gate drives, inverter, and protection features for low and high power circuits Create and document models for HV circuits Develop worst case analysis for HV Circuits Create detailed component desi




voltage

Deletion of Voltage-Gated Calcium Channels in Astrocytes during Demyelination Reduces Brain Inflammation and Promotes Myelin Regeneration in Mice

To determine whether Cav1.2 voltage-gated Ca2+ channels contribute to astrocyte activation, we generated an inducible conditional knock-out mouse in which the Cav1.2 α subunit was deleted in GFAP-positive astrocytes. This astrocytic Cav1.2 knock-out mouse was tested in the cuprizone model of myelin injury and repair which causes astrocyte and microglia activation in the absence of a lymphocytic response. Deletion of Cav1.2 channels in GFAP-positive astrocytes during cuprizone-induced demyelination leads to a significant reduction in the degree of astrocyte and microglia activation and proliferation in mice of either sex. Concomitantly, the production of proinflammatory factors such as TNFα, IL1β and TGFβ1 was significantly decreased in the corpus callosum and cortex of Cav1.2 knock-out mice through demyelination. Furthermore, this mild inflammatory environment promotes oligodendrocyte progenitor cells maturation and myelin regeneration across the remyelination phase of the cuprizone model. Similar results were found in animals treated with nimodipine, a Cav1.2 Ca2+ channel inhibitor with high affinity to the CNS. Mice of either sex injected with nimodipine during the demyelination stage of the cuprizone treatment displayed a reduced number of reactive astrocytes and showed a faster and more efficient brain remyelination. Together, these results indicate that Cav1.2 Ca2+ channels play a crucial role in the induction and proliferation of reactive astrocytes during demyelination; and that attenuation of astrocytic voltage-gated Ca2+ influx may be an effective therapy to reduce brain inflammation and promote myelin recovery in demyelinating diseases.

SIGNIFICANCE STATEMENT Reducing voltage-gated Ca2+ influx in astrocytes during brain demyelination significantly attenuates brain inflammation and astrocyte reactivity. Furthermore, these changes promote myelin restoration and oligodendrocyte maturation throughout remyelination.





voltage

City Utility Trials Voltage Optimization in First for Western Canada

The city utility for Lethbridge, Alberta is starting a voltage optimization trial that is expected to deliver energy savings for customers while reducing overall energy usage in the city’s electricity distribution system.




voltage

ATA663431/54 LIN SBC including LIN Transceiver, FranVoltage Regulator, Window Watchdog and High-Side Switch

ATA663431/54 LIN SBC including LIN Transceiver, FranVoltage Regulator, Window Watchdog and High-Side Switch




voltage

Maharashtra Rural High Voltage Distribution System Expansion Program

Approved project 50193-003 in India.




voltage

High voltage environmental activism


Towering pylons and high tension wires seem to discourage any idea of resistance to environmental destruction in Tehri Garhwal, but the villagers persist. Bharat Dogra reports.




voltage

[ASAP] Stabilized Electrode/Electrolyte Interphase by a Saturated Ionic Liquid Electrolyte for High-Voltage NMC532/Si-Graphite Cells

ACS Applied Materials & Interfaces
DOI: 10.1021/acsami.0c06038




voltage

Structural elucidation of the degradation mechanism of nickel-rich layered cathodes during high-voltage cycling

Chem. Commun., 2020, 56,4886-4889
DOI: 10.1039/D0CC00327A, Communication
Open Access
Jing Lai, Jun Zhang, Zuowei Li, Yao Xiao, Weibo Hua, Zhenguo Wu, Yanxiao Chen, Yanjun Zhong, Wei Xiang, Xiaodong Guo
A splitting of two O3 phases, rather than the often observed O1 phases in the conventional LiCoO2 electrode, was discovered in the LiNi0.85Co0.10Mn0.05O2 at high-voltage region (>4.6 V) by in situ high-resolution synchrotron radiation diffraction.
The content of this RSS Feed (c) The Royal Society of Chemistry




voltage

Investigation of the cathodic interfacial stability of a nitrile electrolyte and its performance with a high-voltage LiCoO2 cathode

Chem. Commun., 2020, 56,4998-5001
DOI: 10.1039/D0CC00049C, Communication
Fang Xian, Jiedong Li, Zhenglin Hu, Qian Zhou, Chen Wang, Chenglong Lu, Zhongyi Zhang, Shanmu Dong, Chunbo Mou, Guanglei Cui
We adopted a SN based deep eutectic electrolyte with the SN as the only solvent and found that the high-state Co ion could be reduced by the SN solvent on the interface of the LiCoO2 electrode, causing a reverse phase change of the LiCoO2.
The content of this RSS Feed (c) The Royal Society of Chemistry