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Text 3Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a dive made with scuba gear because the breathing equipment allows divers to stay underwater longer and dive deeper.The pressure exerted on the human body increases by 1 atmosphere for every 10 meters of depth in seawater, so that at 30 meters in seawater a diver is exposed to a pressure of about 4 atmospheres. The pressure of the gases being breathed must equal the external pressure applied to the body, otherwise breathing is very difficult. Therefore all of the gases in the air breathed by a scuba diver at 40 meters are present at five times their usual pressure. Nitrogen, which composes 80 per cent of the air we breathe, usually causes a balmy feeling of well-being at this pressure. At a depth of 5 atmospheres, nitrogen causes symptoms resembling alcohol intoxication, known as nitrogen narcosis. Nitrogen narcosis apparently results from a direct effect on the brain of the large amounts of nitrogen cause under these pressurized helium does not exert a similar narcotic effect.As a scuba diver descends, the pressure of nitrogen in the lungs increases. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues. The reverse occurs when the diver surfaces; the nitrogen pressure in the lungs falls and the nitrogen diffuses from the tissues into the blood, and from the blood into the lungs. If the return to the surface is too rapid, nitrogen in the tissues and blood cannot diffuse out rapidly enough and nitrogen bubbles are formed. They can cause severe pains, particularly around the joints.Another complication may result if the breath is held during ascent. During ascent from a depth of 10 meters, the volume of air in the lungs will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend and even rupture. This condition is called air embolism. To avoid this event, a diver must ascend slowly, never at a rate exceeding the rise of the exhaled air bubbles, and must exhale during ascent. The word "diffuses" in Para. 3 is closest in meaning to （）
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EPO合同属于固定工期的承包方式，但不应由承包商承担责任原因导致进度延误的情况仍应延长竣工时间。这情况不包括( )
Most people who travel long distances complain of jetlag (喷气飞行时差反应). Jetlag makes business travelers less productive and more prone (21) making mistakes. It is actually caused by (22) of your "body clock"—a small cluster of brain cells that controls the timing of biological (23) . The body clock is designed for a (24) rhythm of daylight and darkness, so that it is thrown out of balance when it (25) daylight and darkness at the "wrong" times in a new time zone. The (26) of jetlag often persist for days (27) the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is (28) that is based on proven (29) pioneering scientific re- search. Dr. Martin Moore-Ere has (30) a practical strategy to adjust the body clock much sooner to the new time zone (31) controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates (32) of the discomfort of jetlag. A successful time zone shift depends on knowing the exact times to either (33) or avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule (34) light exposure depends a great deal on (35) travel plans. Data on a specific flight itinerary (旅行路线) and the individual’s sleep (36) are used to produce a Trip Guide with (37) on exactly when to be exposed to bright light. When the Trip Guide calls (38) bright light you should spend time outdoors if possible. If it is dark outside, or the weather is bad, (39) you are on an aero plane, you can use a special light device to provide the necessary light (40) for a range of activities such as reading, watching TV or working. 36().
Most people who travel long distances complain of jetlag (喷气飞行时差反应). Jetlag makes business travelers less productive and more prone (21) making mistakes. It is actually caused by (22) of your "body clock"—a small cluster of brain cells that controls the timing of biological (23) . The body clock is designed for a (24) rhythm of daylight and darkness, so that it is thrown out of balance when it (25) daylight and darkness at the "wrong" times in a new time zone. The (26) of jetlag often persist for days (27) the internal body clock slowly adjusts to the new time zone. Now a new anti-jetlag system is (28) that is based on proven (29) pioneering scientific re- search. Dr. Martin Moore-Ere has (30) a practical strategy to adjust the body clock much sooner to the new time zone (31) controlled exposure to bright light. The time zone shift is easy to accomplish and eliminates (32) of the discomfort of jetlag. A successful time zone shift depends on knowing the exact times to either (33) or avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule (34) light exposure depends a great deal on (35) travel plans. Data on a specific flight itinerary (旅行路线) and the individual’s sleep (36) are used to produce a Trip Guide with (37) on exactly when to be exposed to bright light. When the Trip Guide calls (38) bright light you should spend time outdoors if possible. If it is dark outside, or the weather is bad, (39) you are on an aero plane, you can use a special light device to provide the necessary light (40) for a range of activities such as reading, watching TV or working. 40().
In The Sorrows of Empire, Chalmers Johnson advances the disturbing claim that the United States’ Cold War-era military power and far-flung base system have, in the last decade, been consolidated in a new form of global imperial rule. The United States, according to Johnson, has become "a military juggernaut intent on world domination."Driven by a triumphalist ideology, an exaggerated sense of threats, and a self-serving military- industrial complex, this juggernaut is tightening its grip on much of the world. The Pentagon has re- placed the State Department as the primary shaper of foreign policy. Military commanders in regional headquarters are modern-day proconsuls, warrior-diplomats who direct the United States’ imperial reach. Johnson fears that this military empire will corrode democracy, bankrupt the nation, spark opposition, and ultimately end in a Soviet-style collapse.In this rendering, the American military empire is a novel form of domination. Johnson de- scribes it as an "international protection racket: mutual defense treaties, military advisory groups, and military forces stationed in foreign countries to" defend" against often poorly defined, overblown, or nonexistent threats." These arrangements create "satellites"—ostensibly independent countries whose foreign relations revolve around the imperial state.Johnson’s previous polemic, Blowbaek, asserted that post-1945 U.S. spheres of influence in East Asia and Latin America were as coercive and exploitative as their Soviet counterparts. The Sorrows of Empire continues this dubious line. Echoing 1960s revisionism, Johnson asserts that the United States’ Cold War security system of alliances and bases was built on manufactured threats and driven by expansionary impulses. The United States was not acting in its own defense; it was exploiting opportunities to build an empire. The Soviet Union and the United States, according to this argument, were more alike than different: both militarized their societies and foreign policies and expanded outward, establishing imperial rule through "hub and spoke" systems of client states and political dependencies.Unfortunately, Johnson offers no coherent theory of why the United States seeks empire. At one point, he suggests that the American military empire is founded on "a vast complex of interests, commitments, and projects." The empire of bases has become institutionalized in the military establishment and has taken on a life of its own. There is no discussion, however, of the forces within U. S. politics that resist or reject empire. As a result, Johnson finds imperialism everywhere and in everything the United States does, in its embrace of open markets and global economic integration as much as in its pursuit of narrow economic gains. It can be inferred from the passage that the Soviet collapse because of().
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