||p.14694 right column bottom paragraph:"To associate the presence of SCFA-producing bacterial communities with the effective increase in the concentration of SCFAs in fecal samples, [investigators] determined the levels of acetic, propionic, butyric, and valeric acids using solid phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) analysis. It is noteworthy that in BF [Burkina Faso, rural African village] children [investigators] found a significantly higher amount of total SCFAs compared with EU [European Union, Florence, Italy] children (one-tailed Student t test, P = 4.5 × 10^-4 Fig. 3A). In particular, propionic and butyric acids are nearly four times more abundant in BF than in EU fecal samples (one-tailed Student t test, P = 1.3 × 10^-3 and P = 1.6 × 10^-4, respectively), whereas acetic and valeric acids were comparable in both groups (one-tailed Student's t test, respectively P = 2.0 × 10^-3 and P = 2.4 × 10^-3 (Fig. 3A and Table S7)."