FIG. 5.

Flow chart demonstrating the combinations of the $\mathrm{\Delta }{\text{CS}}_{\text{sim}}^{\text{X}}$ and ΔCS_exp that yield various classifications of the state markers identified in this study. A threshold of tolerance of 0.2 ppm for ¹³C and 0.5 ppm for ¹⁵N was used to determine if the CS change was significant. FO = fully open, PO = partially open, C = closed, $\mathrm{\Delta }{\text{CS}}_{\text{sim}}^{\text{X}}$ = ${\text{CS}}_{\text{sim}}^{\text{X}}$ − ${\text{CS}}_{\text{sim}}^{\text{Closed}}$, and ΔCS_exp = ${\text{CS}}_{\text{exp}}^{\text{pH}4\text{, act}}$ − ${\text{CS}}_{\text{exp}}^{\text{pH}7.5\text{, deact}}$.