Modeling the Internal Amplification of Current Pulses in Reverse-Biased PNIPN Semiconducting Structures

In frog ventricular strips bathed in Ca-free Ringer's solution containing 6–30 mm/liter Mg and treated with conditioning current pulses, propagation became impaired. An exaggerated foot, or prepotential, was consistently more prominent when the conditioned strip was stimulated from one end than from the other. Occasionally a prepotential in isolation alternated with a prepotential plus action potential response. After further treatment with current pulses, propagation failed in the direction of negative current flow. Thresholds of impaled cells were identical. Bidirectional propagation was restored in Ringer's solution. Conditioning pulses of reversed polarity induced unidirectional propagation in the reverse direction. Propagation in frog sartorius muscle was not blocked under similar conditions. Prepotentials and unidirectional propagation may be explained by junctional transmission from cell to cell.

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Optimisation of welding parameters in pulsed MIG/MAG welding with width-controlled sine-wave current pulses. Part 2: Determination of an optimum material transfer through the arc and a control method

International Journal of Materials and Product Technology ◽

10.1504/ijmpt.2007.013126 ◽

2007 ◽

Vol 29 (1/2/3/4) ◽

pp. 255

Author(s):

Danijel Langus ◽

Viljem Kralj ◽

Janez Grum

Keyword(s):

Control Method ◽

Sine Wave ◽

Mag Welding ◽

Welding Parameters ◽

Material Transfer ◽

Current Pulses ◽

Optimum Material

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Synaptic regulation of cellular properties and burst oscillations of neurons in gastric mill system of spiny lobsters, Panulirus interruptus

Journal of Neurophysiology ◽

10.1152/jn.1984.52.1.54 ◽

1984 ◽

Vol 52 (1) ◽

pp. 54-73 ◽

Cited By ~ 10

Author(s):

D. F. Russell ◽

D. K. Hartline

Keyword(s):

Motor Neurons ◽

Pattern Generator ◽

Stomatogastric Ganglion ◽

Gastric Mill ◽

Panulirus Interruptus ◽

Synaptic Regulation ◽

Gastric Cells ◽

Current Pulses ◽

Regenerative Property ◽

Stimulation Of

The properties of neurons in the stomatogastric ganglion (STG) participating in the pattern generator for the gastric mill rhythm were studied by intracellular current injection under several conditions: during ongoing gastric rhythms, in the nonrhythmic isolated STG, after stimulation of the nerve carrying central nervous system (CNS) inputs to the STG, or under Ba2+ or Sr2+. Slow regenerative depolarizations during ongoing rhythms were demonstrated in the anterior median, cardiopyloric, lateral cardiac, gastropyloric, and continuous inhibitor (AM, CP, LC, GP, and CI) neurons according to criteria such as voltage dependency, burst triggering, and termination by brief current pulses, etc. Experiments showed that regenerative-like behavior was not due to synaptic network interactions. The slow regenerative responses were abolished by isolating the stomatogastric ganglion but could be reestablished by stimulating the input nerve. This indicates that certain CNS inputs synaptically induce the regenerative property in specific gastric neurons. Slow regenerative depolarizations were not demonstrable in gastric mill (GM) motor neurons. Their burst oscillations and firing rate were instead proportional to injected current. CNS inputs evoked a prolonged depolarization in GM motor neurons, apparently by a nonregenerative mechanism. All the gastric cells showed prolonged regenerative potentials under 0.5-1.5 mM Ba2+. We conclude that the gastric neurons of the STG can be divided into three types according to their properties: those with a regenerative capability, a repetitively firing type, and a nonregenerative "proportional" type. The cells are strongly influenced by several types of CNS inputs, including "gastric command fibers."

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Slow active potentials and bursting motor patterns in pyloric network of the lobster, Panulirus interruptus

Journal of Neurophysiology ◽

10.1152/jn.1982.48.4.914 ◽

1982 ◽

Vol 48 (4) ◽

pp. 914-937 ◽

Cited By ~ 49

Author(s):

D. F. Russell ◽

D. K. Hartline

Keyword(s):

Motor Pattern ◽

Membrane Properties ◽

Plateau Potentials ◽

Motor Patterns ◽

Potential Oscillations ◽

Panulirus Interruptus ◽

Pyloric Network ◽

Current Pulses ◽

Voltage Dependent ◽

High Level

1. Neurons in the central pattern generator for the "pyloric" motor rhythm of the lobster stomatogastric ganglion were investigated for the possible involvement of regenerative membrane properties in their membrane-potential oscillations and bursting output patterns. 2. Evidence was found that each class of pyloric-system neurons can possess a capability for generating prolonged regenerative depolarizations by a voltage-dependent membrane mechanism. Such responses have been termed plateau potentials. 3. Several tests were applied to determine whether a given cell possessed a plateau capability. First among these was the ability to trigger all-or-none bursts of nerve impulses by brief depolarizing current pulses and to terminate bursts in an all-or-none fashion with brief hyperpolarizing current pulses. Tests were made under conditions of a high level of activity in the pyloric generator, often in conjunction with the use of hyperpolarizing offsets to the cell under test to suppress ongoing bursting. 4. For each class, the network of synaptic interconnections among the pyloric-system neurons was shown to not be the cause of the regenerative responses observed. 5. Plateau potentials are viewed as a driving force for axon spiking during bursts and as interacting with the synaptic network in the formation of the pyloric motor pattern.

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Speeding Up the Write Operation for Multi-Level Cell Phase Change Memory with Programmable Ramp-Down Current Pulses

Micromachines ◽

10.3390/mi10070461 ◽

2019 ◽

Vol 10 (7) ◽

pp. 461 ◽

Cited By ~ 1

Author(s):

Chenchen Xie ◽

Xi Li ◽

Houpeng Chen ◽

Yang Li ◽

Yuanguang Liu ◽

...

Keyword(s):

Phase Change ◽

Current Source ◽

Phase Change Memory ◽

Operation Time ◽

Access Time ◽

Fully Differential ◽

Current Pulses ◽

Multi Level ◽

The Impact ◽

Change Memory

Multi-level cell (MLC) phase change memory (PCM) can not only effectively multiply the memory capacity while maintaining the cell area, but also has infinite potential in the application of the artificial neural network. The write and verify scheme is usually adopted to reduce the impact of device-to-device variability at the expense of a greater operation time and more power consumption. This paper proposes a novel write operation for multi-level cell phase change memory: Programmable ramp-down current pulses are utilized to program the RESET initialized memory cells to the expected resistance levels. In addition, a fully differential read circuit with an optional reference current source is employed to complete the readout operation. Eventually, a 2-bit/cell phase change memory chip is presented with a more efficient write operation of a single current pulse and a read access time of 65 ns. Some experiments are implemented to demonstrate the resistance distribution and the drift.

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