Table 3.

List of physical laws and constants used to estimate current or flux of ion X.

Parameter/constant	Equation	Number
E-field (e.g., 200 V/m for 25 W/kg)	$E[\text{V}/\text{m}]=45\times {(SAR[\text{W}/\text{kg}]/\sigma [\text{S}/\text{m}])}^{1/2}$	(1)
Membrane capacitance	$C_M[\mathrm{\mu }\text{F}/\text{c}{\text{m}}^2]={\epsilon }_{\mathit{rM}}{\epsilon }_0/d_M\cong 1\left(\text{for}{\epsilon }_{\mathit{rM}}=5,d=5\text{nm}\right)$	(2)
Conductance	$G_X\left[S\right]=\frac{1}{R_X\left[\mathrm{\Omega }\right]}=z_X\times F{u}_X\times c_X\times (a^2/L)$	(3)
Voltage induced by E across membrane ΔUM	$\left[V\right]={10}^{-8}\times E_{\perp }[\text{V}/\text{m}]$	(4)
Ohm’s law	$I_X[A\equiv C/s]=\mathrm{\Delta }{U}_m[\text{V}]\times G_X[S]$	(5)
For UM = 100 mV	$U_M=100\text{mV}\text{at}{C}_M=2\frac{\mathrm{\mu }\text{F}}{{\text{cm}}^2}\text{: 2}\frac{{10}^{-7}C}{{\text{cm}}^2}\triangleq {10}^4\text{ions}/{\mathrm{\mu }\text{m}}^2$	(6)
Drift velocity	$v_X[\mathrm{\mu }\text{m}/\text{s}]=E[\text{V}/\text{cm}]u_X[{10}^{-4}\text{c}{\text{m}}^2/\text{Vs}]$	(7)
Elementary charge	$q_e=1.60\times {10}^{-19}\text{C}$	(8)
Avogadro constant	$N_A=6\times {10}^{23}\text{molecules}/\text{mol}$	(9)
Faraday constant	$F=N_A\times q_e=9.65\times {10}^4\text{C}/\text{mol}$	(10)
Dielectric field constant (free space)	${\epsilon }_0=8.85\times {10}^{-12}\text{C}/\text{V}/\text{m}$	(11)

For the conductance G_X of a channel, we inserted a mean edge length a = 1 nm and membrane thickness L = 5 nm. The conductivity in the intra-/extracellular water was σ = 1.2 S/m (Fig. 3). The charge number was z_X = 1 or 2 (for Ca²⁺). For the mobility u_X, see Table 2.