highly significantp ≤ 0.0001
Statistical significance is indicated in the figures by asterisks, using the following standard notation: * for p ≤ 0.05 (significant), ** for p ≤ 0.01 (very significant), *** for p ≤ 0.001 (highly significant), and **** for p ≤ 0.0001 (extremely significant).