Protective circuit for electroacoustic transducer with Hall element and voice coil temperature rise time constant circuit

1979 ◽  
Vol 66 (6) ◽  
pp. 1917-1918
Author(s):  
Tatsuo Baba ◽  
Yoshito Ohmura ◽  
Hiroshi Fukushima ◽  
Hideo Fukuma
Keyword(s):  
Time Constant ◽  
Temperature Rise ◽  
Rise Time ◽  
Coil Temperature ◽  
Electroacoustic Transducer ◽  
Hall Element

Paired-pulse facilitation in the dentate gyrus: a patch-clamp study in rat hippocampus in vitro

1994 ◽  
Vol 72 (1) ◽  
pp. 326-336 ◽  
Author(s):  
M. Andreasen ◽  
J. J. Hablitz
Keyword(s):  
Patch Clamp ◽  
Dentate Gyrus ◽  
Time Constant ◽  
Rise Time ◽  
Time Course ◽  
Nmda Antagonist ◽  
Paired Pulse ◽  
Stimulation Intensity ◽  
Paired Pulse Facilitation ◽  
Epsc Amplitude

1. Whole-cell patch-clamp recordings were used to study paired-pulse facilitation (PPF) of the lateral perforant path input to the dentate gyrus in thin hippocampal slices. 2. Orthodromic stimulation of the lateral perforant pathway evoked a excitatory postsynaptic current (EPSC) with a latency of 3.3 +/- 0.1 ms (mean +/- SE) that fluctuated in amplitude. The EPSC had a rise time (10-90%) of 2.79 +/- 0.06 ms (n = 35) and decayed with a single exponential time course with a time-constant of 9.14 +/- 0.24 ms (n = 35). No correlation was found between the amplitude of the EPSC and the rise time or decay time-constant. The non-N-methyl-D-aspartate (NMDA) antagonist 6-cyano-7-nitroquinoxaline-2,3-dione completely blocked the EPSC whereas the NMDA antagonist D-aminophosphonovaleric acid (APV) had modest effects. 3. When a test (T-)EPSC was preceded at an interval of 100 ms by a conditioning (C-)EPSC, a significant increase in the amplitude of the T-EPSC was seen in 38 out of 44 trials analyzed from a total of 27 granule cells. The average amount of PPF was 35.7 +/- 2.1%. There was no apparent correlation between the amount of PPF and the stimulation intensity or mean amplitude of the C-EPSC. The time course of the facilitated T-EPSC was not significantly different from that of the C-EPSC. 4. No correlation was found between the amplitude of the C-EPSC and that of the T-EPSC. Estimates of quantal content (mcv) were determined by calculating the ratio of the squared averaged EPSC amplitude (from 48 responses) to the variance of these responses (M2/sigma 2) whereas quantal amplitudes (qcv) were estimated by calculating the ratio of the response variance to average EPSC amplitude (sigma 2/M). PPF was found to be associated with an average increase in mcv of 64.8 +/- 7.2% (n = 38) whereas qcv was decreased by 12.1 +/- 3.8%. 5. The time course of PPF was studied by varying the interval between the C- and T-pulse from 10 to 400 ms while keeping the stimulation intensity constant. Maximal facilitation of the T-EPSC was obtained with interpulse intervals < or = 25 ms where the average facilitation amounted to approximately 70% (n = 6). The decline of facilitation was nearly exponential and was no longer evident with intervals > 350 ms.(ABSTRACT TRUNCATED AT 400 WORDS

Voltage Dependence of the Glycine Receptor–Channel Kinetics in the Zebrafish Hindbrain

1999 ◽  
Vol 82 (5) ◽  
pp. 2120-2129 ◽  
Author(s):  
Pascal Legendre
Keyword(s):  
Time Constant ◽  
Rise Time ◽  
Time Course ◽  
Voltage Dependence ◽  
Good Description ◽  
Glycine Receptor ◽  
Relative Amplitude ◽  
Time Constants ◽  
Low Concentration ◽  
Voltage Dependent

Electrophysiological recordings of outside-out patches to fast-flow applications of glycine were made on patches derived from the Mauthner cells of the 50-h-old zebrafish larva. As for glycinergic miniature inhibitory postsynaptic currents (mIPSCs), depolarizing the patch produced a broadening of the transient outside-out current evoked by short applications (1 ms) of a saturating concentration of glycine (3 mM). When the outside-out patch was depolarized from −50 to +20 mV, the peak current varied linearly with voltage. A 1-ms application of 3 mM glycine evoked currents that activated rapidly and deactivated biexponentially with time constants of ≈5 and ≈30 ms (holding potential of −50 mV). These two decay time constants were increased by depolarization. The fast deactivation time constant increased e-fold per 95 mV. The relative amplitude of the two decay components did not significantly vary with voltage. The fast component represented 64.2 ± 2.8% of the total current at −50 mV and 54.1 ± 10% at +20 mV. The 20–80% rise time of these responses did not show any voltage dependence, suggesting that the opening rate constant is insensitive to voltage. The 20–80% rise time was 0.2 ms at −70 mV and 0.22 ms at +20 mV. Responses evoked by 100–200 ms application of a low concentration of glycine (0.1 mM) had a biphasic rising phase reflecting the complex gating behavior of the glycine receptor. The time constant of these two components and their relative amplitude did not change with voltage, suggesting that modal shifts in the glycine-activated channel gating mode are not sensitive to the membrane potential. Using a Markov model to simulate glycine receptor gating behavior, we were able to mimic the voltage-dependent change in the deactivation time course of the responses evoked by 1-ms application of 3 mM glycine. This kinetics model incorporates voltage-dependent closing rate constants. It provides a good description of the time course of the onset of responses evoked by the application of a low concentration of glycine at all membrane potentials tested.

Analysis and reduction of coil temperature rise in electromagnetic forming

2015 ◽  
Vol 225 ◽  
pp. 185-194 ◽  
Author(s):  
Quanliang Cao ◽  
Xiaotao Han ◽  
Zhipeng Lai ◽  
Qi Xiong ◽  
Xiao Zhang ◽  
...  
Keyword(s):  
Temperature Rise ◽  
Electromagnetic Forming ◽  
Coil Temperature

Analysis of coil temperature rise in electromagnetic forming with coupled cooling method

2020 ◽  
Vol 63 (1) ◽  
pp. 45-58 ◽  
Author(s):  
Li Qiu ◽  
Kui Deng ◽  
Yantao Li ◽  
Xi Tian ◽  
Qi Xiong ◽  
...  
Keyword(s):  
Temperature Rise ◽  
Electromagnetic Forming ◽  
Cooling Method ◽  
Coil Temperature

scholarly journals Pengujian Sistem Pengendalian Temperatur pada Prototipe Heat Exchanger Berbasis PID

2021 ◽  
Vol 13 (2) ◽  
pp. 81-91
Author(s):  
Asepta Surya Wardhana ◽  
Hana Amelinda Azizah ◽  
Chalidia Nurin Hamdani
Keyword(s):  
Heat Exchanger ◽  
Time Constant ◽  
Rise Time ◽  
Direct Synthesis ◽  
Settling Time ◽  
Trial And Error ◽  
Proportional Integral Derivative ◽  
Set Point ◽  
Servo Valve ◽  
Proportional Integral

Rancang bangun sistem pengendalian temperatur heat exchanger berbasis PID artinya mengendalikan temperatur air dingin keluaran heat exchanger yang telah dirancang agar sesuai dengan nilai set point melalui pengendalian mode controller PID (Proportional Integral Derivative). Pengendalian temperatur dilakukan dengan melibatkan pengendalian laju aliran air panas. Ketika set point temperatur air dingin heat exchanger dinaikkan maka servo valve semakin membuka sehingga laju aliran air panas bertambah. Software Delphi 7 digunakan untuk menampilkan hasil berupa angka dan grafik dari data proses sistem pengendalian temperatur. Nilai parameter mode kontroler PID didapat melalui metode trial and error. Sebagai pembanding, dilakukan perhitungan PID ideal menggunakan metode direct synthesis untuk diterapkan pada kalkulasi pengendalian sistem di dalam mikrokontroler Arduino. Perhitungan PID ideal memerlukan hasil bump test dari masing?masing variabel proses. Hasil analisis data dan grafik interface menunjukkan bahwa kenaikan set point dari 25? menjadi 32? pada temperatur air keluaran heat exchanger mengakibatkan bukaan servo valve mendekati bukaan penuh dan berada pada kondisi hunting system saat temperatur telah mencapai set point. Dari hasil pengujian diperoleh Time Constant 89,744 detik, Settling Time 127,232 detik dan Rise Time 127,8 detik.

Postsynaptic Receptor Occupancy During Evoked Transmission at Striatal GABAergic Synapses In Vitro

2000 ◽  
Vol 84 (2) ◽  
pp. 771-779 ◽  
Author(s):  
Eva Rumpel ◽  
Jan C. Behrends
Keyword(s):  
Time Constant ◽  
Decay Time ◽  
Rise Time ◽  
Receptor Occupancy ◽  
Decay Time Constant ◽  
Peak Amplitude ◽  
Postsynaptic Currents ◽  
Quantal Size ◽  
Convolution Model ◽  
Quantal Responses

The effect of benzodiazepines (BZs) on GABAA-ergic synaptic responses depends on the control receptor occupancy: the BZ-induced enhancement of receptor affinity can lead to greater peak amplitudes of quantal responses only when, under normal conditions, receptors are not fully saturated at peak. Based on this fact, receptor occupancy at the peak of spontaneous miniature inhibitory postsynaptic currents (mIPSCs) has been assessed in various mammalian neuronal preparations. To use the same principle with compound (or multiquantal), action potential–evoked IPSCs, complications introduced by quantal asynchrony in conjunction with the BZ-induced increase in the decay time of the quantal responses have to be overcome. We used a simple analytic convolution model to calculate expected changes in the rise time and amplitude of postsynaptic currents when the decay time constant, but not the peak amplitude, of the underlying quantal responses is increased, this being the expected BZ effect at saturated synapses. Predictions obtained were compared with the effect of the BZ flunitrazepam on IPSCs recorded in paired pre- and postsynaptic whole cell voltage-clamp experiments on striatal neurons in cell culture. In 22 pairs, flunitrazepam (500 nM) reliably prolonged the decay of IPSCs (49 ± 19%, mean ± SE) and in 18 of 22 cases produced an enhancement in their peak amplitude that varied markedly between 3 and 77% of control (26.0 ± 5.3%). The corresponding change in rise time, however (+0.38 ± 0.11 ms, range −0.8 to +1.3 ms) was far smaller than calculated for the observed changes in peak amplitude assuming fixed quantal size. Because therefore an increase in quantal size is required to explain our findings, postsynaptic GABAA receptors were most likely not saturated during impulse-evoked transmission at these unitary connections. The peak amplitudes of miniature IPSCs in these neurons were also increased by flunitrazepam (500 nM, +26.8 ± 6.6%), and their decay time constant was increased by 26.3 ± 7.3%. Using these values in our model led to a slight overestimate of the change in compound IPSC amplitude (+28 to +30%).

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