The effects of the pause to pulse ratio in the regime of pulsating overpotential on the formation of honeycomb-like structures

A 2D axi-symmetric theoretical model of dielectric porous media in intermittent microwave (IMW) thermal process was developed, and the electromagnetic energy, multiphase transport, phase change, large deformation, and glass transition were taken into consideration. From the simulation results, the mass was mainly carried by the liquid water, and the heat was mainly carried by liquid water and solid. The diffusion was the dominant mechanism of the mass transport during the whole process, whereas for the heat transport, the convection dominated the heat transport near the surface areas during the heating stage. The von Mises stress reached local maxima at different locations at different stages, and all were lower than the fracture stress. A material treated by a longer intermittent cycle length with the same pulse ratio (PR) tended to trigger the phenomena of overheat and fracture due to the more intense fluctuation of moisture content, temperature, deformation, and von Mises stress. The model can be extended to simulate the intermittent radio frequency (IRF) process on the basis of which one can select a suitable energy source for a specific process.

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Robust Digital Current Control Based on Adaptive Disturbance Estimation for PMSM Drives with Low Pulse Ratio

2018 21st International Conference on Electrical Machines and Systems (ICEMS) ◽

10.23919/icems.2018.8549265 ◽

2018 ◽

Cited By ~ 2

Author(s):

Haitao Yang ◽

Yongchang Zhang ◽

Jiejunyi Liang ◽

Nong Zhang ◽

Paul Walker

Keyword(s):

Current Control ◽

Disturbance Estimation ◽

Pulse Ratio

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High-Performance Current Regulation for Low-Pulse-Ratio Inverters

IEEE Transactions on Industry Applications ◽

10.1109/tia.2012.2229252 ◽

2013 ◽

Vol 49 (1) ◽

pp. 149-158 ◽

Cited By ~ 34

Author(s):

Brendan P. McGrath ◽

Stewart Geoffrey Parker ◽

Donald Grahame Holmes

Keyword(s):

High Performance ◽

Current Regulation ◽

Pulse Ratio

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Diurnal Changes in Exocytosis and the Number of Synaptic Ribbons at Active Zones of an on-Type Bipolar Cell Terminal

Journal of Neurophysiology ◽

10.1152/jn.00364.2006 ◽

2006 ◽

Vol 96 (4) ◽

pp. 2025-2033 ◽

Cited By ~ 50

Author(s):

Court Hull ◽

Keith Studholme ◽

Stephen Yazulla ◽

Henrique von Gersdorff

Keyword(s):

Synaptic Vesicle ◽

Bipolar Cell ◽

Bipolar Cells ◽

Synaptic Ribbons ◽

Diurnal Changes ◽

Synaptic Vesicle Exocytosis ◽

Pulse Ratio ◽

Vesicle Exocytosis ◽

Active Zones ◽

Vesicle Pool

The number and morphology of synaptic ribbons at photoreceptor and bipolar cell terminals has been reported to change on a circadian cycle. Here we sought to determine whether this phenomenon exists at goldfish Mb-type bipolar cell terminals with the aim of exploring the role of ribbons in transmitter release. We examined the physiology and ultrastructure of this terminal around two time points: midday and midnight. Nystatin perforated-patch recordings of membrane capacitance ( Cm) revealed that synaptic vesicle exocytosis evoked by short depolarizations was reduced at night, even though Ca2+ currents were larger. The efficiency of exocytosis (measured as the Δ Cm jump per total Ca2+ charge influx) was thus significantly lower at night. The paired-pulse ratio remained unchanged, however, suggesting that release probability was not altered. Hence the decreased exocytosis likely reflects a smaller readily releasable vesicle pool at night. Electron microscopy of single sections from intact retinas averaged 65% fewer ribbons at night. Interestingly, the number of active zones did not change from day to night, only the probability of finding a ribbon at an active zone. Additionally, synaptic vesicle halos surrounding the ribbons were more completely filled at night when these on-type bipolar cells are more hyperpolarized. There was no change, however, in the physical dimensions of synaptic ribbons from day to night. These results suggest that the size of the readily releasable vesicle pool and the efficiency of exocytosis are reduced at night when fewer ribbons are present at bipolar cell terminal active zones.

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Influence of AlN and GaN Pulse Ratios in Thermal Atomic Layer Deposited AlGaN on the Electrical Properties of AlGaN/GaN Schottky Diodes

Coatings ◽

10.3390/coatings10050489 ◽

2020 ◽

Vol 10 (5) ◽

pp. 489 ◽

Cited By ~ 1

Author(s):

Hogyoung Kim ◽

Seok Choi ◽

Byung Joon Choi

Keyword(s):

Photoelectron Spectroscopy ◽

Schottky Diodes ◽

Charge Trapping ◽

Negative Temperature ◽

Atomic Layer ◽

Algan Layer ◽

Pulse Ratio ◽

Current Voltage ◽

Frenkel Emission ◽

A Charge

Atomic layer deposited AlGaN with different AlN and GaN pulse ratios (2:1, 1:1, and 1:2) was used to prepare AlGaN/GaN Schottky diodes, and their current transport mechanisms were investigated using current–voltage (I–V) and capacitance–voltage (C–V) measurements. Under low reverse bias condition, the sample with the pulse ratio of 2:1 was explained by Poole–Frenkel emission and the negative temperature dependence for the sample with the pulse ratio of 1:2 was associated with the acceptor levels in the AlGaN layer. Fast interface traps at 0.24–0.29 eV were observed for the samples with the pulse ratios of 1:1 and 1:2, whereas bulk traps at ~0.34 eV were observed for the sample with the pulse ratio of 2:1. Higher trap densities were obtained from the C–V hysteresis measurements when the pulse ratios were 1:1 and 1:2, indicating the presence of a charge trapping interfacial layer. According to the X-ray photoelectron spectroscopy spectra, the pulse ratio of 2:1 was found to have less oxygen-related defects in the AlGaN layer.

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Capsaicin causes robust reduction in glycinergic transmission to rat hypoglossal motor neurons via a TRPV1-independent mechanism

Journal of Neurophysiology ◽

10.1152/jn.00059.2019 ◽

2019 ◽

Vol 121 (4) ◽

pp. 1535-1542 ◽

Cited By ~ 4

Author(s):

Prajwal P. Thakre ◽

Mark C. Bellingham

Keyword(s):

Motor Neurons ◽

Half Width ◽

Cationic Current ◽

Pulse Ratio ◽

Capsaicin Application ◽

Trpv1 Receptors ◽

Voltage Dependent ◽

Brainstem Slices ◽

Trpv1 Antagonist ◽

Activity Dependent

The effect of capsaicin on glycinergic synaptic transmission to juvenile rat hypoglossal motor neurons in acute brainstem slices was evaluated in the presence of TTX. Capsaicin caused a robust decrease in miniature IPSC frequency, amplitude, and half-width, showing that this effect is independent of action potential generation. In the presence of capsazepine, a classic TRPV1 antagonist, capsaicin was still able to reduce spontaneous inhibitory postsynaptic current (IPSC) amplitude and frequency. We further investigated whether the effect of capsaicin on glycinergic transmission to hypoglossal motor neurons is pre- or postsynaptic in nature by recording pairs of evoked IPSCs. Interestingly, capsaicin also reduced evoked IPSC amplitude without affecting paired-pulse ratio, indicating a postsynaptic mechanism of action. Significant reduction was also observed in evoked IPSC half-width, rise time, and decay tau. We also show that capsaicin does not have any effect on either transient (It) or sustained (Is) potassium currents. Finally, we also show that the hyperpolarization-activated cationic current (Ih) also remains unchanged after capsaicin application. NEW & NOTEWORTHY Capsaicin reduces the amplitude of quantal and evoked glycinergic inhibitory neurotransmission to brainstem motor neurons without altering activity-dependent transmitter release. This effect of capsaicin is not due to activation of TRPV1 receptors, as it is not blocked by capsazepine, a TRPV1 receptor antagonist. Capsaicin does not alter voltage-dependent potassium current or the hyperpolarization-activated cationic current in brainstem motor neurons.

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