All distal segmental branches of the PA will be ligated to maintain the pressure throughout the catheterized segmental branch. An initial pressure of 25 mmHg will be obtained by inflating the vessel with normal saline. The lobar PA and the main segmental branches' diameters will be measured from vascular adventitia to adventitia. The lobar PA and the main segmental arteries will be sealed using the Harmonic Scalpel Ace+. The sealing will be performed with an intravascular pressure of 25 mmHg in order to simulate normal human PA pressures.