Many things can cause a bleb to rupture, such as changes in air pressure or a very sudden deep breath. Often, people who experience a primary spontaneous pneumothorax have no prior sign of illness; the blebs themselves typically do not cause any symptoms and are visible only on medical imaging.
SEATO came to an end in 1977 after just 22 years of existence. Lesson Summary. After World War II, the United States and other countries were concerned about the spread of communism around the world. On Feb. 19, 1955, the Southeast Asia Treaty Organization (SEATO) was created to help combat this spread. Of the eight member countries, only two (Thailand and the Philippines) were actually located in Southeast Asia.
2.1 A political and military Alliance. NATOâs essential purpose is to safeguard the freedom and security of its members through political and military means.POLITICAL-NATO promotes democratic values and encourages consultation and cooperation on defence and security issues to build trust and, in the long run, prevent conflict.ATO is an alliance of countries from Europe and North America. It provides a unique link between these two continents for consultation and cooperation in the field of defence and security, and the conduct of multinational crisis-management operations.