Fig. 2

An example of improved fitting result after modification of the original RD-NLS method. The unsatisfactory performance of the original RD-NLS occurred when some inversion time (TI) values were very close such that the choice of minimal TI closest to 0 can be sensitive to noise. a A poor fitting result when the RD-NLS method was applied without any modification of the script. b A correction after the modification, which considered three candidate samples for polarity restorations (see arrows)