Correction: Intracellular Water Exchange for Measuring the Dry Mass, Water Mass and Changes in Chemical Composition of Living Cells. - Francisco Feijó Delgado; Nathan Cermak; Vivian C. Hecht; Sungmin Son; Yingzhong Li; Scott M. Knudsen; Selim Olcum; John M. Higgins; Jianzhu Chen; William H. Grover; Scott R. Manalis (PLoS ONE, 2013)