题目内容
Sleep and wakefulness, once considered to be the light and dark of consciousness, no longer seem to differ so sharply. To sleep does not mean to drown in an ocean of darkness. Actually, sleep is not a unitary state; it involves many shades or degree of detachment from the surrounding world. While sleep may feel like a blanket of darkness punctuated by dreams—a time when the mind is asleep—nothing could be less true. All night long a person drifts down and up through different levels of consciousness, as if on waves. With laboratory methods, researchers have been able to chart the typical stages of the journey into sleep.
The journey starts while the subject is still awake but beginning to relax. His brain waves, which have been low, rapid, and irregular, begin to show a new pattern. This new pattern, which is known as alpha rhythm, is an even electrical pulsation of about nine to 12 cycles per second. Most people do not know what the alpha state feels like, but during the last few years researchers have been able to teach subjects how to recognize and control their alpha rhythm.
When their EEG shows an alpha rhythm, the subjects are notified, either by a sound or by the appearance of a color on a screen. Because the alpha state tends to be pleasant and relaxed, the ability to sustain it can help tense people ease their passage into sleep. A moment of tension, a loud noise, an attempt to solve a problem, however, and the alpha rhythm may vanish.
As the subject passes through the gates of the unconsciousness, his alpha waves grow smaller, and his eyes roll very slowly. For a moment, he may wake up during this early part of the descent, alerted by a sudden spasm that causes his body to jerk. Like the brain waves, this spasm is a sign of neural changes within. Known as the myoclonic jerk, it is caused by a brief burst of activity in the brain. Although it is related to epileptic seizures, the myoclonic jerk is normal in all human sleep. It is gone in a fraction of a second, after which descent continues. The subject has not felt the peculiar transformation, but now he is said to be truly asleep.
This passage states that a person is really asleep only
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Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
The rebuilding of the World Trade Center is in many ways a memorial to those who lost their lives in the 2001 September 11 attacks and it is a tribute that these buildings will also be built to the highest green building standards. N.Y. Governor George Pataki announced that the Freedom Tower, World Trade Center Office Towers 2, 3, and 4, as well as the World Trade Center Memorial and Memorial Museum will all be designed to achieve the U.S. Green Building Council's (USGBC) LEED Gold certification requirements.
This groundbreaking announcement was made five years after the devastating attacks and includes an entire package of energy and environmental measures that will be incorporated into the design of the World Trade Center redevelopment. Plans for the Freedom Tower and other facilities at the World Trade Center site will feature state-of-the-art energy technologies to better protect environmental resources; utilize renewable energy sources, and maximize energy efficiency.
These buildings join over half a billion square feet of construction projects already involved with the LEED program, including World Trade Center 7, which was certified as LEED Gold in March 2006. These facilities will also be built to a design standard that is 20 percent more efficient than the New York Energy Conservation Construction Code.
"The decision to achieve LEED Gold is a fitting tribute to the importance of the reconstruction of Ground Zero. Using LEED sends a clear message that our buildings must be safe, healthy places for us to live and work," said Rick Fedrizzi, President, CEO & Founding Chair, U.S. Green Building Council. "New York is to be commended for its leadership; the World Trade Center buildings will stand as a symbol of New York's Courage and commitment to a healthy and sustainable future."
Governor Pataki also announced an agreement with Silverstein Properties that calls for the Freedom Tower and each of the World Trade Center Office Towers to utilize cutting edge fuel cell technology to increase efficiency and provide secure clean on-site power generation. These fuel cell installations, totaling 4.8 MW of power generation, will together constitute one of the largest fuel cell installations in the world.
"The redevelopment will be a global example of green building design and a constant reminder of our commitment to break the cycle of dependence on foreign energy," said the Governor. "By moving forward with state-of-the-art design and guidelines, New York will once again show the world our ingenuity, innovation and commitment to building a stronger, brighter future for all."
"LEED certification for the rebuilding of the World Trade Center complex demonstrates the resiliency (恢复) of the United States," Fedrizzi continued. "Not only is our nation restoring the areas devastated by the terrorist attacks, but we are also doing so in a way that highlights our commitment m—and belief in—the future."
LEED Gold certification requires ______.
【32】
The old standard weight weighed ______ when it is humid.
【37】
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