No one is sure how the ancient Egyptians built the pyramids near Cairo. But a new study suggests they used a little rock‘n'roll. Long-ago builders could have attached wooden pole s to the stones and rolled then across the sand, the scientists say.
“Technically, I think what they're proposing is possible,” physicist Daniel Bonn said.
People have long puzzled over how the Egyptians moved such huge rocks. And there's no obvious answer. On average, each of the two million big stones weighed about as much as a large pickup truck. The Egyptians somehow moved the stone blocks to the pyramid site from about one kilometer away.
The most popular view is that Egyptian workers slid the blocks along smooth paths. Many scientists suspect workers first would have put the blocks on sleds(滑板). Then they would have dragged them along paths. To make the work easier, workers may have lubricated the paths either with wet clay or with the fat from cattle. Bonn has now tested this idea by building small sleds and dragging heavy objects over sand.
Evidence from the sand supports this idea. Researchers found small amounts of fat, as well as a large amount of stone and the remains of paths.

However, physicist Joseph West thinks there might have been a simpler way , who led the new study . West said , “I was inspired while watching a television program showing how sleds might have helped with pyramid construction . I thought , ‘Why don't they just try rolling the things?'“A square could be turned into a rough sort of wheel by attaching wooden poles to its sides , he realized . That , he notes , should make a block of stone” a lot easier to roll than a square”.
So he tried it.
He and his students tied some poles to each of four sides of a 30-kilogram stone block. That action turned the block into somewhat a wheel. Then they placed the block on the ground.
They wrapped one end of a rope around the block and pulled. The researchers found they could easily roll the block along different kinds of paths. They calculated that rolling the block required about as much force as moving it along a slippery(滑的)path.
West hasn't tested his idea on larger blocks, but he thinks rolling has clear advantages over sliding. At least, workers wouldn't have needed to carry cattle fat or water to smooth the paths.

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    The kindly “Chinese Fortune Grandpa” wearing Han Chinese clothing and holding a fortune bag debuted （亮相） at the Imperial Ancestral Shrine in Beijing on the day after Christmas. The final image of the Chinese gift-giver was selected through a global design competition against “Santa Claus”, according to a report by Guangming Daily.

    Many Chinese cities have been filled with Christmas neon lights, Christmas songs, Christmas trees, and the images of “Santa Claus”in recent days. As a matter of fact, foreign festivals are becoming more popular than certain traditional Chinese festivals among the Chinese people, particularly the youth. “Certain traditional festivals have died out because people have forgotten their spiritual meanings, ”said noted writer Feng Jicai. More and more Chinese people are beginning to exchange gifts on Valentine's Day and Christmas. However, many of them know nothing about Chinese New Year pictures or sugarcoated figurines（小糖人）, and have never heard suona music. Certain folk customs on the Dragon Boat Festival, Tomb Sweeping Day, and other traditional festivals have gradually disappeared. Under such circumstances, even the “Chinese Fortune Grandpa” is unlikely to defeat “Santa Claus”.

    However, it is not a bad thing to some extent. It constantly reminds people to restore the “true face” of traditional festivals. China has listed traditional Tomb Sweeping Day, Dragon Boat Festival and Mid-Autumn Festival as legal holidays, which brings more paid leaves to the public, and helps to awake the public awareness of traditional festivals.

    In modern society, festival is a carrier of culture and its meaning largely depends on their understandings and usages by people. Compared with foreign festivals, traditional Chinese festivals are not inferior （次于） in cultural meanings, but lack of fashion sought by modern people. If people do not appreciate the historical culture contained by traditional festivals, and only take pleasure-seeking as the most important, the significance of traditional festivals will fade away and the inheritance （继承） of fine traditional culture will be cut off.

    Tu Youyou, an 84-year-old female（女性）scientist, became the first Chinese to win a Nobel Prize in science on Oct 5. Before that, she ever won the 2011 Lasker Award for finding out artemisinin (Qinghaosu), which saved millions of lives. She was grateful（感激的）for the Lasker prize, but said, “It is just a scientist' duty. I will go on fighting for the health of all humans.”

    Tu kept her work in the 1960s and 1970s. In that age, Malaria (疟疾) could took away people's health. Scientists all over the world had already tried over 240, 000 times but failed. Tu Youyou, a member of the Academy of Traditional Chinese Medicine, Beijing, began to study Chinese herbs.

    Before 2011, people didn't know Tu very much. Many friends played jokes with her “the Professor of Three None's” : no degree（学位）, no study experience abroad, not a member of any Chinese national colleges. But she is hard-working. She read a lot of traditional Chinese medicine books and did a lot of researches on the disease.

    In February, 2012, Tu was named National Outstanding Females (One of the Ten) Tu is now a model of Chinese medical workers.

    Why is pink or purple a color for girls and blue or brown for boys?

The answer depends largely on cultural values as well as personal experiences. To the Egyptians, green was a color that represented the hope and joy of spring, while for Muslims, it means heaven. Red is a symbol of good luck in many cultures. In China, children are given money in a red envelope to bring good fortune in the New Year. For many nations, blue is a symbol of protection and religious beliefs. Greek people often wear a blue necklace hoping to protect themselves against evils (灾祸).

    People's choice of colors is also influenced by their bodies' reactions (反应) toward them. Green is said to be the most restful color. It has the ability to reduce pain and relax people both mentally and physically. People who work in green environment have been found to have fewer stomachaches.

Red can cause a person's blood pressure to rise and increase people's appetites (食欲). Many decorators will include different shades of red in the restaurant. Similarly, many commercial (商业的)websites will have a red “Buy Now” button because red is a color that easily catches a person's eye.

    Blue is another calming color. Unlike red, blue can cause people to lose appetite. So if you want to eat less, some suggest that eating from blue plates can help.

    The next time you are deciding on what to wear or what color to decorate your room, think about the color carefully.

    Reading may be fundamental, but how the brain gives meaning to letters on a page has been a mystery. Two new studies fill in some details on how the brains of efficient readers handle words. One of the studies, published in the April 30 Neuron, suggests that a visual-processing area of the brain recognizes common words as whole units. Another study, published online April 27 in PLOSONE, makes it known that the brain operates two fast parallel systems for reading, linking visual recognition of words to speech.

    Maximilian Riesenhuber, a neuroscientist at Georgetown University in Washington, D. C. , wanted to know whether the brain reads words letter by letter or recognizes words as whole objects. He and his colleagues showed sets of real words or nonsense(无意义的词语)words to volunteers undergoing FMRI scans. The words differed in only one letter, such as “farm” and “form” or “soat” and “poat”, or were completely different, such as “farm” and “coat”or “poat” and “hime”.The researchers were particularly interested in what happens in the visual word form area, or VWFA, an area on the left side of the brain just behind the ear that is involved in recognizing words.

    Riesenhuber and his colleagues found that neurons(神经元)in the VWFA respond strongly to changes in real words. Changing “farm” to “form”, for example, produced as great a change in activity as changing “farm” to“coat”, the team reports in Neuron. The area responded slowly to single-letter changes in made-up words.

    The data suggests that readers grasp real words as whole objects, rather than focusing on letters or letter combinations. And as a reader's exposure to a word increases, the brain comes to recognize the shape of the word. “Meaning is passed on after recognition in the brain”, Riesenhuber says.

    The researchers don't yet know how longer and less familiar words are recognized, or if the brain can be trained to recognize nonsense words as a unit.