Eat to Live

    A meager diet may give you health and long life, but it"s not much fun—and it might not even be necessary. We may be able to hang on to¹ most of that youthful vigor even if we don"t start to diet until old age.
    Stephen Spindler and his colleagues from the UniversityofCaliforniaatRiversidehave found that some of an elderly mouse"s liver genes can be made t006F behave as they did when the mouse was young simply by limiting its food for four weeks. The genetic rejuvenation won"t reverse other damage caused by time for the mouse, but could help its liver metabolize drugs or get rid of toxins².
    Spindler"s team fed three mice a normal diet for their whole lives, and fed another three on half-rations³. Three more mice were switched from the normal diet to half-feed³ for a month when they were 34 months old—equivalent to about 70 human years.
　　The researchers checked the activity of 11,000 genes from the mouse livers, and found that 46 changed with age in the normally fed mice. The changes were associated with things like inflammation and free radical production⁴—probably bad news for mouse health. In the mice that had dieted all their lives, 27 of those 46 genes continued to behave like young genes. But the most surprising finding was that the mice that only started dieting in old age also benefited from 70 per cent of these gene changes.
　　“This is the first indication that thee effects kick in⁵ pretty quickly,” says Huber Warner from the National Institute on Aging near Washington, D. C.
　　No one yet knows if calorie works in people as it does in mice, bus Spindler is hopeful. “There"s attracting and tempting evidence out there that it will work,” he says.
　　If it does work in people, there might be good reasons for rejuvenating the liver. As we get older, out bodies are les efficient at metabolizing drugs, for example. A brief period of time of dieting, says Spindler, could be enough to make sure a drug is effective.
　　But Spindler isn"t sure the trade-off is worth it⁶. “The mice get less disease, they live longer but they"re hungry,” he says. “Even seeing what a diet does, it"s still hard to go to a restaurant and say: "I can only eat half of that".”
　　Spindler hopes we soon won"t need to diet at all. His company, Life Span Genetics inCalifornia, is looking for drugs that have the effects of calorie restriction.

词汇：
meager/"mi:gə(r)/adj.不足的 

youthful/ ˈju:θfl/adj.   有青春活力的
vigor/ "vɪgə(r)/n. 精力，活力 

metabolize / mə"tæbəlaɪz/vt.  使(一种物质)进入新陈代谢过程
genetic / dʒəˈnetɪk/adj.  基因的 

rejuvenation  n. 恢复活力，返老还童
liver/ ˈlɪvə(r)/n.  肝脏  

toxin/ ˈtɒksɪn/ n.  毒素 

ration/ "ræʃn/ n.   定量
calorie / "kælərɪ/n.  卡 (热量的单位) 

inflammation / ˌɪnfləˈmeɪʃn/n. 炎症，发炎
trade-off   n.交换，交易

rejuvenate/ rɪ"dʒu:vəneɪt/ vt. 使恢复活力

Why does the author mention an elderly mouse in paragraph 2?

A:To describe the influence of old age on mice B:To illustrate the effect of meager food on mice C:To tell us how mice’s liver genes behave D:To inform us of the process of metabolizing drugs

Eat to Live

    A meager diet may give you health and long life, but it"s not much fun—and it might not even be necessary. We may be able to hang on to¹ most of that youthful vigor even if we don"t start to diet until old age.
    Stephen Spindler and his colleagues from the UniversityofCaliforniaatRiversidehave found that some of an elderly mouse"s liver genes can be made t006F behave as they did when the mouse was young simply by limiting its food for four weeks. The genetic rejuvenation won"t reverse other damage caused by time for the mouse, but could help its liver metabolize drugs or get rid of toxins².
    Spindler"s team fed three mice a normal diet for their whole lives, and fed another three on half-rations³. Three more mice were switched from the normal diet to half-feed³ for a month when they were 34 months old—equivalent to about 70 human years.
　　The researchers checked the activity of 11,000 genes from the mouse livers, and found that 46 changed with age in the normally fed mice. The changes were associated with things like inflammation and free radical production⁴—probably bad news for mouse health. In the mice that had dieted all their lives, 27 of those 46 genes continued to behave like young genes. But the most surprising finding was that the mice that only started dieting in old age also benefited from 70 per cent of these gene changes.
　　“This is the first indication that thee effects kick in⁵ pretty quickly,” says Huber Warner from the National Institute on Aging near Washington, D. C.
　　No one yet knows if calorie works in people as it does in mice, bus Spindler is hopeful. “There"s attracting and tempting evidence out there that it will work,” he says.
　　If it does work in people, there might be good reasons for rejuvenating the liver. As we get older, out bodies are les efficient at metabolizing drugs, for example. A brief period of time of dieting, says Spindler, could be enough to make sure a drug is effective.
　　But Spindler isn"t sure the trade-off is worth it⁶. “The mice get less disease, they live longer but they"re hungry,” he says. “Even seeing what a diet does, it"s still hard to go to a restaurant and say: "I can only eat half of that".”
　　Spindler hopes we soon won"t need to diet at all. His company, Life Span Genetics inCalifornia, is looking for drugs that have the effects of calorie restriction.

词汇：
meager/"mi:gə(r)/adj.不足的 

youthful/ ˈju:θfl/adj.   有青春活力的
vigor/ "vɪgə(r)/n. 精力，活力 

metabolize / mə"tæbəlaɪz/vt.  使(一种物质)进入新陈代谢过程
genetic / dʒəˈnetɪk/adj.  基因的 

rejuvenation  n. 恢复活力，返老还童
liver/ ˈlɪvə(r)/n.  肝脏  

toxin/ ˈtɒksɪn/ n.  毒素 

ration/ "ræʃn/ n.   定量
calorie / "kælərɪ/n.  卡 (热量的单位) 

inflammation / ˌɪnfləˈmeɪʃn/n. 炎症，发炎
trade-off   n.交换，交易

rejuvenate/ rɪ"dʒu:vəneɪt/ vt. 使恢复活力

What can be inferred about completely normally fed mice mentioned in the passage?

A:They will not experience free radical production B:They will experience more genetic rejuvenation in their lifetime C:They have more old liver genes to behave like young genes D:They are more likely to suffer from inflammation

After-birth Depression Blamed for¹ Woman"s Suicide

    A new mother apparently suffering from postpartum mental illness fell to her death from a narrow 12th-floor ledge of a Chicagohotel, eluding the lunging grasp of firemen called to help.
　　The Chicago Tribune² reported Tuesday that the mother of a 3-month-old daughter, Melanie Stokes，41，was said to be suffering from+ a severe form of after-birth depression called postpartum psychosis，an extremely rare biological response to rapidly changing hormonal levels that can result in⁴ hallucinations, delusions, severe insomnia and a drastic departure from reality.
　　"That was a monster in my daughter"s brain,” said Stokes’ mother, Carol Blocker. “The medicine took no effect at all, while her grief was so strong that nothing could make up for it.⁵ I"m just glad she didn"t take her daughter with her. ”
　　Virtually all new mothers get postpartum .blues, also called the "baby blues⁶"，which are brief episodes of irritability, moodiness and weepiness. About 20 per cent of birthing women experience postpartum depression, which can be triggered by hormonal changes, sleeplessness and the pressures of being a new mother. It is often temporary and highly treatable.
　　But The Tribune said what scientists suspect Stokes was battling, postpartum psychosis, is even more extreme and is considered a psychiatric emergency.⁷ During postpartum psychosis — a very real disorder that affects less than 1 percent of women, according to the National Institute of Mental Health⁸一 a mother might hear voices, have visions, feel extremely agitated and be at risk of harming the child or herself.
　　Often the consequences are tragic. In 1987，Sheryl Masip of California told a judge that postpartum psychosis made her drive a Volvo over her 6-week-old son. Latrena Pixley of Washington, D. C.⁹，said the disorder was why she smothered her 6-week-old daughter in 1992. And last year,Judy Kirby，a 31-year-old Indianapolis¹⁰ mother allegedly suffering from postpartum psychosis，sped into oncoming traffic¹¹ and plowed into¹² a minivan，killing seven youngsters， including three of her own.

词汇：

postpartum/ ˌpəʊst"pɑ:təm/adj. 产后的

grief / gri:f/n.不幸，灾难
ledge/ ledʒ/n. （自墙壁突出的）壁架；架状突出物

blues / blu:z/n.忧郁，沮丧
elude/ ɪ"lu:d/vt.（巧妙地）躲避，逃脱；困惑，难倒
irritability / ˌɪrɪtə"bɪlətɪ/n.急躁，易怒；兴奋性；过敏
moodiness / "mu:dɪnəs/n.喜怒无常，易怒；忧郁

weepiness 好哭，欲哭
lunge / lʌndʒ/vi.冲刺，猛向前冲

depression/ dɪ"preʃn/n. 抑郁症
psychosis 精神病

agitated/ saɪ"kəʊsɪs/adj. 焦虑不安的，激动的
hormonal/ hɔ:"məʊnl/adj. 激素的

smother / ˈsmʌðə(r)/v.使窒息，使憋死
hallucination / həˌlu:sɪˈneɪʃn/n.幻觉

allegedly/ ə"ledʒɪdlɪ/adv. 根据（人们）宣称
delusion / dɪˈlu:ʒn/n.妄想

insomnia / ɪnˈsɒmniə/n.失眠症

drastic/ ˈdræstɪk/adj. 激烈的；极端的
plow / plaʊ/n.犁，刨；破浪前进

minivan/ ˈmɪnivæn/n. 微型货车

注释：

Which of the following is NOT a symptom of postpartum psychosis?

A:Visions B:Delusions C:Inflamed breast D:Serious sleeplessness

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

Each day the men ran for approximately eight hours.

A:Right B:Wrong C:mentioned

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

In the middle of the day: the men usually stopped running.

A:Right B:Wrong C:mentioned

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

They sometimes felt sick because it was so hot.

A:Right B:Wrong C:mentioned

Across the Deserts

　　The SaharaDesertis the largest desert in the world. It stretches across Africa fromSenegaltoEgypt. TheSaharaDesertis an unfriendly environment. During the day it"s very hot, and at night it’s sometimes very cold. It is also difficult to find water in theSahara.

　　In 2006, Kevin Lin, Ray Zahab, and Charlie Engle decided to do something very difficult. They made the decision to run across the Sahara Desert 4,300 miles (6,920km). It seemed impossible to do, but they wanted to try. The three men liked to test themselves, and this would be a very big test.

　　On the morning of November 2, Kevin, Ray, and Charlie started their trip across theSahara. Every morning they began running at 5:00. At11 a.m. they stopped and rested until 5 p.m. Then they ran again until 9:30 in the evening. Each day they ran about 40 miles (64 km). Every day it was the same thing. They got up and ran. They listened to music on their iPods, and they ran and ran.

　　Kevin, Ray, and Charlie needed to eat a lot of food during their trip. Most people need about 2,000 calories of food each day. Kevin, Ray, and Charlie needed between 6,000 and 9,000 calories every day. That"s a lot of food! They also needed to drink a lot of water.

　　The three men had some problems on their trip, and many times they wanted to quit and go home. It was often very hot (140°F/60°C) during the day, and the heat made them sick. Their legs and feet hurt. Sometimes it was very windy, and they couldn"t see. One time they got lost. But they didn"t quit. After 111 days, Kevin, Ray; and Charlie successfully finished their trip across theSaharaDesert. They hugged each other and put their hands in the water of theRed Sea. Then they ran to a hotel to take a long shower.

　　词汇：

　　Stretch / strɛtʃ / v. 延伸，伸展

　　Calorie / "kælərɪ / n. 卡(路里)，小卡，大卡

　　Quit / kwɪt / v. 停止，放

　　注释：

On their trip across the desert: the three men ran through five countries.

A:Right B:Wrong C:mentioned