Recent summer temperatures in parts of Australia were high enough to melt asphalt. As global warming speeds up the heat and climatic events increase, many plants may be unable to cope. But at least one species of eucalyptus tree can resist extreme heat by continuing to “sweat” when other essential processes stop, a new study finds.

    As plants change sunlight into food, or photosynthesize (光合作用), they absorb carbon dioxide through pores on their leaves. These pores also release water via transpiration(蒸腾), which circulates nutrients through the plant and helps cool it by evaporation(蒸发). But exceptionally high temperatures are known to greatly reduce photosynthesis—and most existing plant models suggest this should also decrease transpiration, leaving trees in danger of fatally overheating. Because it is difficult for scientists to control and vary trees' conditions in their natural environment, little is known about how individual species handle this situation.

    Ecologist John Drake of the S.U.N.Y. College of Environmental Science and Forestry and his colleagues grew a dozen Parramatta red gum (Eucalyptus parramattensis) trees in large, climate-controlled plastic pods that separated the trees from the surrounding forest for a year in Richmond, Australia. Six of the trees were grown at surrounding air temperatures and six at temperatures three degrees Celsius higher. The researchers withheld (扣留) water from the surface soil of all 12 trees for a month to imitate a mild dry spell, then induced a four-day “extreme” heat wave: They raised the maximum temperatures in half of the pods（three with surrounding temperatures and three of the warmer ones）— to 44 degrees ℃.

    Photosynthesis ground to a near halt in the trees facing the artificial heat wave. But to the researchers' surprise, these trees continued to transpire at close-to-normal levels, effectively cooling themselves and their surroundings. The trees grown in warmer conditions coped just as well as the others, and photosynthesis rates bounced back to normal after the heat wave passed, Drake and his colleagues reported online in Global Change Biology.

    The researchers think the Parramatta red gums were able to effectively sweat — even without photosynthesis — because they are particularly good at tapping into water deep in the soil. But if a heat wave and a severe drought (干旱) were to hit at the same time and the groundwater was exhausted, the trees may not be so lucky, Drake says.

    Other scientists call the finding encouraging. “It's definitely good news,” says Trevor Keenan, an ecologist at Lawrence Berkeley National Laboratory, who was not part of the study. “It would be very interesting to know how this translates to other species,” he adds. Drake hopes to conduct similar experiments with trees common in North America.

    It happened to me recently. I was telling someone how much I had enjoyed reading Barack Obama's Dreams From My Father and how it had changed my views of our President. A friend I was talking to agree with me that it was, in his words ,“a brilliantly written book” However, he then went on to talk about Mr. Obama in a way which suggested he had no idea of his background at all. I sensed that I was talking to a book liar.

    And it seems that my friend is not the only one. Approximately two thirds of people have lied about reading a book which they haven't. In the World Book Day's “Report on Guilty Secrets”, Dreams From My Father is at number 9. The report lists ten books, and various authors, which people have lied about reading, and as I'm not one to lie too often (I'd hate to be caught out), I will admit here and now that I haven't read the entire top ten. But I'm pleased to say that, unlike 42 percent of people, I have read the book at number one, Gorge Orwell's 1984. I think it's really brilliant.

    The World Book Day report also has some other interesting information in it. It says that many people lie about having read Jane Austin Austen, Charles Dickens, Fyodor Dostoevsky (I haven't read him, but haven't lied about it either) and Herman Melville.

    Asked why they lied, the most common reason was to “impress” someone they are speaking to. This could be tricky if the conversation became more in-depth!

    But when asked which authors they actually enjoy, people named J.K. Rowling, John Grisham, Sophie Kinsella (ah, the big sellers, in other words). Forty-two percent of people asked admitted they turned to the back of the book to read the end before finishing this story (I will come clean: I do this and am astonished that 58 percent said they had never done so.).

    Last April, on a Sunday, we took one of our “nowhere” drives. My husband was quietly driving along a back road. I was occupied in the front passenger seat watching the scenery.

    I noticed out of the corner of my eye that my husband was struggling to look out of my window. This frightened me, since his eyes should be on the road in front of him. I asked him what he was looking at out of the windows, and he quietly replied, “Nothing.”

    After a few minutes, I looked over at my husband and noticed a tear running down his cheek. I asked him what was wrong. This time he told me, “I was just thinking about Pop and a story he had once told.” It had something to do with Pop, his friend from childhood, and I wanted to know the story, so I asked him to share it with me.

    He said, “When I was about 8 years old, Pop and I were out fishing and he told me that the pine trees know when it is Easter.”

    I had no idea what he meant by that, so I pressed him for more information.

    He continued on… “The pine trees start their new growth in the weeks before Easter because spring is drawing near. If you look at the tops of the pine trees, you will see the yellow shoots(嫩芽). As the days get closer to Easter Sunday, the tallest shoot will branch off and form a cross. By the time Easter Sunday comes around, you will see that most of the pine trees will have small yellow crosses on all of the tallest shoots.”

    I turned to look out of the window and I couldn't believe my eyes. It was a week before Easter, and you could see all of the trees with the tall yellow shoots stretching to the sky.

    The tallest ones shone in the sunlight like rows of tiny golden crosses. May you find your Easter season filled with beautiful golden crosses!

    At a daycare center in Texas, children were playing outside. One of the children was Jessica Mc Clure. She was 18 months old. Her mother, who worked at the daycare center, was watching the children. Suddenly Jessica fell and disappeared. Jessica's mother screamed and ran to her.

    A well was in the yard of the center. The well was only eight inches across and a rock always covered it. But children had moved the rock. When Jessica fell, she fell right into the well.

    Jessica's mother reached inside the well, but she couldn't feel Jessica. She dialed 911 for help. Men from the fire department arrived. They discovered that Jessica was about 20 feet down in the well. For the next hour the men talked and planned Jessica's rescue.

    "We can't go down into the well," they said."It's too narrow. So, we're going to drill a hole next to the well. Then we'll drill a tunnel across to Jessica. When we reach her, we'll bring her through the tunnel and up through our hole."

    The men began to drill the hole at 11 a.m. on Wednesday, October 14, 1987. The men had a difficult job; they were drilling through solid rock. During her days in the well, Jessica sometimes asked for her mother. Sometimes she slept, sometimes she cried and sometimes she sang.

    All over the world, people waited for news of Jessica. Everyone worried about her.

At 8 p.m. on Friday, October 16, men reached Jessica and brought her up from the well. She was soon sent to hospital. Jessica was dirty, hungry, thirsty and tired. Her feet and forehead were badly injured. But Jessica was alive.

    After Jessica's rescue, one of the rescuers made a metal cover for the well, saying," To Jessica, with love from all of us."

My Favorite Sweater

By Bonnie Highsmith Taylor

Earth's next superpower

The following countries have been sitting on hidden talents. And now they're about to fly.

NIGERIA (尼日利亚)

Nigeria says it pumps out as much oil as the other two oil-producing countries, Kuwait and Iraq. All this oil is cycling cash into the Nigerian economy and creating extremely rich businessmen. Analysts say that if Nigeria can improve its schools and technology, it could balloon into the world's 13th largest economy by 2050, right between Turkey and Italy. If that reason is not enough for optimism, Nigeria's president also has the sunniest name of any world leader: Goodluck Jonathan.

VIETNAM

As agriculture has given way to industry, unemployment in Vietnam has dropped. What's Vietnam's trick? It's ready to work. Other countries' laborers aren't as cheap as they used to be, which makes Vietnam a relative bargain for companies that need new factories abroad. However, the country has almost no railroads, its highways are in poor condition, and its largest city has just one airport, which was built before the Vietnam War. So what's the use of producing export-ready goods if there's no convenient way to ship them? The good thing is that, however, officials are widening highways, building a new airport and so on.

CHILE (智利)

Pipes, computers, motors, and your microwave all have one thing in common: They're made with copper (铜). Copper makes the world go round. And luckily for Chile, it's got about a third of the planet's copper supply. It just needs a way to dig it up and the government is pouring money into the country's mines.