Table 1. Occurrence of WT-to-NT and NT-to-WT transformations.

Lipid	No. of experiments	NT formations	NT-to-WT transitions
DPhPC	54	40	36 (17*)
DNPC	64	38	36 (4*)
OPC/OPE/Chol	15	15	15 (0*)

^*With pressure application.