scholarly journals Effect of interelectrode distance on bioelectric parameters of electro-biosystems

2021 ◽  
Vol 36 (3) ◽  
pp. 123-126
Author(s):  
I. Rusyn ◽  
O. Medvediev ◽  
V. Diachok
Keyword(s):  
Interelectrode Distance

Interelectrode distance and warning signal interval and the evaluation of clinical electrical shock

2009 ◽  
Vol 24 (4) ◽  
pp. 285-293
Author(s):  
Pieter Duker ◽  
Monique Mulder ◽  
Nienke Scheffer
Keyword(s):  
Warning Signal ◽  
Interelectrode Distance ◽  
Electrical Shock

Burst-Suppression Ratio on Electrocorticography Depends on Interelectrode Distance

2016 ◽  
Vol 33 (2) ◽  
pp. 127-132 ◽  
Author(s):  
Mihai Moldovan ◽  
Alexandru Calin ◽  
Vishakhadatta M. Kumaraswamy ◽  
Diana Braver ◽  
Mirela V. Simon
Keyword(s):  
Suppression Ratio ◽  
Burst Suppression ◽  
Interelectrode Distance

Effects of Intravenous Anesthetics on Atrial Wavelength and Atrioventricular Nodal Conduction in Guinea Pig Heart

1996 ◽  
Vol 85 (2) ◽  
pp. 393-402 ◽  
Author(s):  
Charles A. Napolitano ◽  
Pekka M. J. Raatikainen ◽  
Jeffrey R. Martens ◽  
Donn M. Dennis
Keyword(s):  
Guinea Pig ◽  
Conduction Velocity ◽  
Cycle Length ◽  
Rank Order ◽  
Interelectrode Distance ◽  
Atrial Pacing ◽  
Dependent Manner ◽  
Frequency Dependent ◽  
His Bundle ◽  
Atrioventricular Nodal Conduction

Background Supraventricular tachydysrhythmias such as atrial fibrillation frequently complicate the perioperative period. Two electrophysiologic factors critical to the pathogenesis of supraventricular tachydysrhythmias are: 1) atrial wavelength, the product of atrial conduction velocity (CV) and effective refractory period (ERP), and 2) atrioventricular nodal conduction. Modulation of these factors by drugs has important clinical ramifications. The authors studied the effects of propofol, thiopental, and ketamine on atrial wavelength and atrioventricular nodal function in guinea pig isolated atrial trabeculae and hearts, respectively. Methods Electrocardiogram recordings in superfused atrial tissue were obtained using hanging microelectrodes. A stimulating and two recording electrodes were placed on a single atrial trabecula, and the interelectrode distance was measured. Atrial ERP determinations were made using a premature stimulus protocol. The time (t) required for a propagated impulse to traverse the interelectrode distance (d) was measured. Conduction velocity was calculated as d/t. Langendorff-perfused guinea pig hearts were instrumented for low atrial pacing (cycle length = 300 ms) and for measurements of stimulusto-His bundle interval, an index of atrioventricular nodal conduction. To investigate the frequency-dependent behavior of the atrioventricular node, computer-based measurements were made of Wenckebach cycle length (WCL) and atrioventricular nodal ERP. Results Thiopental significantly prolonged atrial ERP in a concentration-dependent manner, whereas propofol and ketamine had no significant effect on atrial refractoriness. In contrast, ketamine caused a dose-dependent decrease in atrial CV, but propofol and thiopental had no significant effect on CV. Therefore, thiopental, ketamine, and propofol caused an increase, a decrease, and no change, respectively, in atrial wavelength. All anesthetics caused a concentration-dependent prolongation of the stimulus-to-His bundle interval, atrioventricular nodal ERP, and WCL. However, on an equimolar basis, significant differences in potencies were found. The concentrations of drug that caused a 20% increase in ERP (ERP20) and WCL (WCL20) for propofol, thiopental, and ketamine were 14 +/- 2 microM, 26 +/- 3 microM, and 62 +/- 11 microM, and 17 +/- 2 microM, 50 +/- 1 microM, and 123 +/- 19 microM (mean +/- SEM), respectively. Therefore, the rank order of potency for frequency-dependent atrioventricular nodal effects is propofol > thiopental > ketamine. Conclusion The authors' results indicate that propofol would be most effective at filtering atrial impulses during supraventricular tachydysrhythmias, whereas thiopental would be most effective at preventing atrial reentrant dysrhythmias. In contrast, ketamine may be most likely to promote atrial reentry while having minimal effect on atrioventricular nodal conduction.

Interelectrode distance and amplitude of the scalp EEG

1985 ◽  
Vol 60 (4) ◽  
pp. 287-292 ◽  
Author(s):  
Charles M. Epstein ◽  
Gail P. Brickley
Keyword(s):  
Interelectrode Distance ◽  
Scalp Eeg

scholarly journals Effect of interelectrode distance on dc magnetron current–pressure characteristics

2018 ◽  
Vol 946 ◽  
pp. 012150
Author(s):  
Yu A Mankelevich ◽  
A F Pal ◽  
A N Ryabinkin ◽  
A O Serov
Keyword(s):  
Interelectrode Distance ◽  
Pressure Characteristics

scholarly journals Time-resolved quantification of the dynamic extracellular space in the brain during short-lived event: methodology and simulations

2019 ◽  
Vol 121 (5) ◽  
pp. 1718-1734 ◽  
Author(s):  
Kevin C. Chen ◽  
Yi Zhou ◽  
Hui-Hui Zhao
Keyword(s):  
Extracellular Space ◽  
Volume Fraction ◽  
Interelectrode Distance ◽  
Operating Parameters ◽  
High Fidelity ◽  
Phase Lag ◽  
Time Resolved ◽  
Time Pattern ◽  
Waveform Amplitude ◽  
The Brain

Two macroscopic parameters describe the interstitial diffusion of substances in the extracellular space (ECS) of the brain, the ECS volume fraction α and the diffusion tortuosity λ. Past methods based on sampling the extracellular concentration of a membrane-impermeable ion tracer, such as tetramethylammonium (TMA+), can characterize either the dynamic α( t) alone or the constant α and λ in resting state but never the dynamic α( t) and λ( t) simultaneously in short-lived brain events. In this work, we propose to use a sinusoidal method of TMA+ to provide time-resolved quantification of α( t) and λ( t) in acute brain events. This method iontophoretically injects TMA+ in the brain ECS by a sinusoidal time pattern, samples the resulting TMA+ diffusion waveform at a distance, and analyzes the transient modulations of the amplitude and phase lag of the sampled TMA+ waveform to infer α( t) and λ( t). Applicability of the sinusoidal method was verified through computer simulations of the sinusoidal TMA+ diffusion waveform in cortical spreading depression. Parameter sensitivity analysis identified the sinusoidal frequency and the interelectrode distance as two key operating parameters. Compared with other TMA+-based methods, the sinusoidal method can more accurately capture the dynamic α( t) and λ( t) in acute brain events and is equally applicable to other pathological episodes such as epilepsy, transient ischemic attack, and brain injury. Future improvement of the method should focus on high-fidelity extraction of the waveform amplitude and phase angle. NEW & NOTEWORTHY An iontophoretic sinusoidal method of tetramethylammonium is described to capture the dynamic brain extracellular space volume fraction α and diffusion tortuosity λ. The sinusoidal frequency and interelectrode distance are two key operating parameters affecting the method’s accuracy in capturing α( t) and λ( t). High-fidelity extraction of the waveform amplitude and phase lag is critical to successful sinusoidal analyses.

Effect of Interelectrode Distance on Sural Nerve Action Potential Parameters

2008 ◽  
Vol 87 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Christopher T. Plastaras ◽  
Christina M. Marciniak ◽  
Daniel P. Sipple ◽  
Kirsten Gross DʼAmore ◽  
Cynthia Garvan ◽  
...  
Keyword(s):  
Action Potential ◽  
Sural Nerve ◽  
Interelectrode Distance ◽  
Nerve Action ◽  
Potential Parameters

The effects of interelectrode distance on electromyographic amplitude and mean power frequency during incremental cycle ergometry

2006 ◽  
Vol 151 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Moh H. Malek ◽  
Terry J. Housh ◽  
Jared W. Coburn ◽  
Joseph P. Weir ◽  
Richard J. Schmidt ◽  
...  
Keyword(s):  
Cycle Ergometry ◽  
Interelectrode Distance ◽  
Mean Power ◽  
Mean Power Frequency ◽  
Power Frequency
Sign in / Sign up

Export Citation Format

Share Document