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||P.6664 right column 2nd paragraph: "Ions and charged metabolites contribute to the dielectric properties of the intracellular environment. The static dielectric constant of pure water is 78.4 at 25 °C (primary source), but dissolved ions can decrease this value substantially due to the tendency of water molecules to align with local electric fields caused by nearby ions (ref 78)... Based on measurements by Hasted et al., [investigators] estimate that in physiological solutions the dielectric constant of water would be reduced by only ∼2 units (i.e., to ∼76) primarily because of K+: given the complexity of the intracellular environment it is questionable whether this estimate is accurate."