SkyMark, JetStar and others offer flights from Tokyo and other major cities in Japan to Naha. Low cost airlines such as Air Asia Japan and Peach Aviation now fly between Okinawa (Naha) and Tokyo Narita, Osaka Kansai respectively. Most Japanese airlines do offer deep discounts, but they MUST be bought in advance.
The alveoli are open to the environment so alveolar pressure (i.e. the pressure inside the lungs) is really the same as atmospheric pressure. Intrapleural pressure is the pressure of the air in the pleural cavity in which the lung sits (the space between the lung tissue and the chest wall).
Ward HE, Nicholas TE. The alveolar epithelium comprises two main cell types: the alveolar type I and alveolar type II cell. The type I cell is a complex branched cell with multiple cytoplasmic plates that are greatly attenuated and relatively devoid of organelles; these plates represent the gas exchange surface in the alveolus.