Pulmonary arterial hypertension is a rare but severe disease with an estimated five-year survival rate of only 57% after diagnosis, according to the Registry to Evaluate Early And Long-term PAH disease management (REVEAL), which registers data from patients in the United States.
Concentration of elements in the ocean relative to the total concentration in the bulk silicate Earth (BSE). Of all the elements, only Cl and Br have a significant fraction in the ocean (see inset), indicating the extreme hydrophilic character for the heavier halogens.
Xenon is a trace gas found in the Earth's atmosphere to the extent of about one part in 20 million, According to the Los Alamos National Laboratory. This makes it very rare. It is also found in Mars' atmosphere at 0.08 ppm. This noble gas can also be found down on Earth.