Time course of transmembrane voltage induced by time-varying electric fields—a method for theoretical analysis and its application

1998 ◽  
Vol 45 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Tadej Kotnik ◽  
Damijan Miklavčič ◽  
Tomaž Slivnik
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Martin L. Pall

Abstract Millimeter wave (MM-wave) electromagnetic fields (EMFs) are predicted to not produce penetrating effects in the body. The electric but not magnetic part of MM-EMFs are almost completely absorbed within the outer 1 mm of the body. Rodents are reported to have penetrating MM-wave impacts on the brain, the myocardium, liver, kidney and bone marrow. MM-waves produce electromagnetic sensitivity-like changes in rodent, frog and skate tissues. In humans, MM-waves have penetrating effects including impacts on the brain, producing EEG changes and other neurological/neuropsychiatric changes, increases in apparent electromagnetic hypersensitivity and produce changes on ulcers and cardiac activity. This review focuses on several issues required to understand penetrating effects of MM-waves and microwaves: 1. Electronically generated EMFs are coherent, producing much higher electrical and magnetic forces then do natural incoherent EMFs. 2. The fixed relationship between electrical and magnetic fields found in EMFs in a vacuum or highly permeable medium such as air, predicted by Maxwell’s equations, breaks down in other materials. Specifically, MM-wave electrical fields are almost completely absorbed in the outer 1 mm of the body due to the high dielectric constant of biological aqueous phases. However, the magnetic fields are very highly penetrating. 3. Time-varying magnetic fields have central roles in producing highly penetrating effects. The primary mechanism of EMF action is voltage-gated calcium channel (VGCC) activation with the EMFs acting via their forces on the voltage sensor, rather than by depolarization of the plasma membrane. Two distinct mechanisms, an indirect and a direct mechanism, are consistent with and predicted by the physics, to explain penetrating MM-wave VGCC activation via the voltage sensor. Time-varying coherent magnetic fields, as predicted by the Maxwell–Faraday version of Faraday’s law of induction, can put forces on ions dissolved in aqueous phases deep within the body, regenerating coherent electric fields which activate the VGCC voltage sensor. In addition, time-varying magnetic fields can directly put forces on the 20 charges in the VGCC voltage sensor. There are three very important findings here which are rarely recognized in the EMF scientific literature: coherence of electronically generated EMFs; the key role of time-varying magnetic fields in generating highly penetrating effects; the key role of both modulating and pure EMF pulses in greatly increasing very short term high level time-variation of magnetic and electric fields. It is probable that genuine safety guidelines must keep nanosecond timescale-variation of coherent electric and magnetic fields below some maximum level in order to produce genuine safety. These findings have important implications with regard to 5G radiation.


2020 ◽  
pp. 1-37
Author(s):  
Manuel A. Gómez ◽  
Goncalo Monteiro

We devise an endogenous growth model in which agents’ utility depends not only on current consumption but also on the pleasure of anticipated future consumption. We consider the case in which agents derive satisfaction from their own anticipatory feelings—inward-looking or internal anticipation—and the case in which agents derive utility from anticipation of other people’s future consumption—outward-looking or external anticipation. We characterize the effects of introducing a forward-looking consumption reference on the dynamics of the economy. Whereas the inward-looking economy features transitional dynamics, the outward-looking economy does not. The distortions caused by the externality in the economy with external habits can be corrected by subsidizing income at a time-varying rate or by means of a tax on consumption at a decreasing rate. We contrast the equilibrium dynamics of our specification to the more standard specification of the habit formation consumption reference point. Numerical simulations supplement the theoretical analysis.


1993 ◽  
Vol 265 (3) ◽  
pp. H899-H909 ◽  
Author(s):  
D. Burkhoff ◽  
P. P. De Tombe ◽  
W. C. Hunter

This study focuses on elucidating how ventricular afterloading conditions affect the time course of change of left ventricular pressure (LVP) throughout the cardiac cycle, with particular emphasis on revealing specific limitations in the time-varying elastance model of ventricular dynamics. Studies were performed in eight isolated canine hearts ejecting into a simulated windkessel afterload. LVP waves measured (LVPm) during ejection were compared with those predicted (LVPpred) according to the elastance theory. LVPm exceeded LVPpred from a time point shortly after the onset of ejection to the end of the beat. The instantaneous difference between LVPm and LVPpred increased steadily as ejection proceeded and reached between 45 and 65 mmHg near end ejection. This was in large part due to an average 35-ms prolongation of the time to end systole (tes) in ejecting compared with isovolumic beats. The time constant of relaxation was decreased on ejecting beats so that, despite the marked prolongation of tes, the overall duration of ejecting contractions was not greater than that of isovolumic beats. The results demonstrate a marked ejection-mediated enhancement and prolongation of ventricular pressure-generating capacity during the ejection phase of the cardiac cycle with concomitant acceleration of relaxation. None of these factors are accounted for by the time-varying elastance theory.


2017 ◽  
Vol 45 (6) ◽  
pp. 913-917
Author(s):  
Matej Klas ◽  
Ladislav Moravsky ◽  
Stefan Matejcik ◽  
Branislav Radjenovic ◽  
Marija Radmilovic-Radjenovic

2002 ◽  
Vol 85 (12) ◽  
pp. 10-19
Author(s):  
Masakazu Arakawa ◽  
Hiroaki Yamamoto ◽  
Satoshi Tanaka ◽  
Norifumi Yamada

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