Before revision:  the index i, 1 i H, is the hydrophobicity classification of atoms. N_i( ) is the mean number of water molecules in the first hydration layer that directly contact to the atoms with the hydrophobicity degree i;
After revision:  the index i, 1 i  ) is the mean number of water molecules in the first hydration layer that directly contact to the atoms with the hydrophobicity degree i;