Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.We learn from Paragraph 1 that __________.
| A．an emerald and a ruby are names of diamonds. |
| B．it’s not difficult to tell where the gem was mined. |
| C．appearances help to identify the origin of gemstones. |
| D．diamonds from different places may appear the same. |
Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?
| A．To look for more gemstones. |
| B．To encourage violent civil wars. |
| C．To reduce the trade in blood minerals. |
| D．To develop the economy. |
Which of the following facts most probably helps McManus and her team in identifying the origin of stones?
| A．Heat can turn ice into water or water into steam. |
| B．Gemstones from the same area produce similar light patterns. |
| C．Laser can change a miniscule part of the gemstone into plasma. |
| D．Materialytics has already collected patterns from thousands of gemstones. |
From the last two paragraphs, what can be inferred about the laser technique?
| A．It is ready for commercial use. |
| B．People can use the new tool to find more gemstones. |
| C．It can significantly reduce the gemstones trade in blood minerals. |
| D．It will bring about a revolutionary change in identifying the origin of minerals. |
The author wrote this passage mainly to __________.
| A．tell us how to identify the origin of diamonds. |
| B．introduce a laser technique in identifying a stone’s origin |
| C．prove identifying the origin of gemstones are difficult |
| D．attract our attention to reducing trade in blood minerals |
A mouse looked through a crack in the wall to see the farmer and his wife opening a package: What food might it contain? He was astonished to discover that it was a mouse trap!
Retreating（撤退） to the farmyard, the mouse declared the warning, “There is a mouse trap in the house, there is a mouse trap in the house.”
The chicken clucked and scratched, raised her head and said, “Mr Mouse, I can tell you this is a grave concern to you, but it is of no consequence to me, I cannot be bothered by it.”
The mouse turned to the pig and told him, “There is a mouse trap in the house.” “I am so sorry, Mr Mouse,” sympathized the pig, “but there is nothing I can do about it but pray; be assured that you are in my prayers.”
The mouse turned to the cow, who replied, “A mouse trap, am I in grave danger, huh?”
So the mouse returned to the house, head down and depressed to face the farmer’s mouse trap alone.
That very night a sound was heard throughout the house, like the sound of a mouse trap catching its prey. The farmer’s wife rushed to see what was caught. In the darkness, she did not see that it was an evil snake whose tail the trap had caught. The snake bit the farmer’s wife. The farmer rushed her to the hospital. She returned home with a fever. Now everyone knew to treat a fever with fresh chicken soup, so the farmer took his hatchet to the farmyard for the soup’s main ingredient. His wife’s sickness continued so that friends and neighbors came to sit with her around the clock. To feed them, the farmer butchered the pig. The farmer’s wife did not get well, in fact, she died, and so many people came for her funeral. The farmer had the cow slaughtered to provide meat for all of them to eat.
So the next time you hear that someone is facing a problem and think that it does not concern you, remember that when the least of us is threatened, we are all at risk.We may infer that the passage is most probably a ______.
| A．fairy tale | B．fable |
| C．science fiction | D．news report |
We could see from the passage that the mouse was ______.
| A．kind and warm-hearted | B．well-informed |
| C．good at cheating others | D．foolish and rude |
Which of the following is TRUE according to the passage?
| A．The pig was comparatively less friendly than the others in the farmyard. |
| B．The mouse trap that the mouse discovered was not a practical one. |
| C．The farmer and his wife trapped an evil snake that night. |
| D．The farmer’s family was in fact poor and they had no friends. |
The underlined word “ingredient” (Paragraph 7) refers to ______.
| A．the mouse | B．the pig |
| C．the snake | D．the chicken |
Studies have documented that smiling is a universal and effective way to lift mood. But in the latest research on the power of the smile, researchers led by Marcus Munafo of the University of Bristol in England found that even seeing smiles on the faces of others can have a profound effect on a person's tendency toward violence or aggression — that is, as long as that person recognizes the smile as one of happiness, and not as a sneer (讥笑)．
Munafo and his colleagues conducted a series of experiments involving normal adults and highly aggressive teens referred to a youth program, either by educational authorities or the courts. About 70% of the teens already had a criminal record.
In the first experiment, 40 healthy adults, aged 1830, looked at facial expressions on the computer ranging from happy to angry with increasingly difficult ones to discern in between. Participants were asked how angry they felt and then had to rate the images as displaying either happiness or anger — there was no option for “unclear” or “unable to tell”. From these ratings, the scientists could generate a score of their preference toward happiness or anger.
Previous research found that aggressive people — including violent offenders — tend to consider even a common expression as an unfriendly one. “You looking at me？” can easily turn a simple question into a tragic fight.
Based on their original scores, half of the participants were then told by the computer that some of the unclear faces that they had rated as angry should have been scored as happy. This was intended to guide them toward judging the inbetween faces more positively. The other 20 received feedback that simply proved their first choices, creating a control group.
After this training, both groups were tested again and the group that received the biased (有偏见的) feedback shifted its ratings of unclear faces toward the happy side. Participants were also asked to rate their level of angry feelings again after completing the second round of testing. Those who were trained to consider unclear faces as happier reported feeling less angry afterward.
The researchers next focused on the 46 adolescents from the high risk youth program. These teens completed the same testing, but both the youth and the staff reported on the teens' levels of aggressive behavior before the testing started and for two weeks afterward. The teens trained to interpret unclear facial expressions more positively were significantly less aggressive two weeks later.
“The results of our experiments strongly suggest that the understanding of emotional facial expressions plays a causal role in subjective anger and aggressive behavior，”the authors conclude.
That doesn't mean that smiles alone are the answer to violence among adolescents — previous research in which antisocial youth were trained to better recognize emotions, for example, did not have any effect on their level of aggressive behavior. But this earlier study focused on improving teens' understanding of clear facial signals, not unclear ones. Since unclear signals are more likely to be misunderstood, it may be that violent behavior in some youth exists with their constant misunderstanding of angry expressions where they don't exist, which push them to aggressive responses. The findings suggest that helping young people, particularly those easy to be violent, to learn to give others the benefit of the doubt when they see what they think is a threatening face could help end the vicious (恶性的) cycle of violence.The underlined word “discern” (Paragraph 3) means ________.
| A．display obviously | B．identify clearly |
| C．describe correctly | D．value properly |
According to Munafo's research, the anger and violent behavior in some youths resulted from ____.
| A．their misunderstanding of facial emotions of others |
| B．their lack in knowledge of emotion recognition |
| C．their inborn tendency toward violence or aggression |
| D．their experience of being offended by others on purpose |
The method Munafo and his colleagues used in their research is ________.
| A．field investigation |
| B．case study |
| C．observation and analysis |
| D．experiment and comparison |
What happens to the participants after receiving certain feedbacks?
| A．They can interpret unclear facial expressions. |
| B．They put an end to their aggressive behavior. |
| C．They tend to judge the inbetween faces positively. |
| D．It makes no difference in their level of aggressive behavior. |
Which of the following will Munafo and his group probably agree with?
| A．Just smile as much as possible. |
| B．Misunderstanding is the root of violence. |
| C．Seeing smiles can lower aggression. |
| D．Control our anger to avoid violence and aggression. |
Since the beginning of the year, smog has covered parts of North China. In January, Beijing saw only five days without smog. The rising PM2.5 readings terrified many people, and some health experts said that whenever the smog gets serious, hospitals receive more patients suffering acute respiratory (呼吸系统) and heart diseases.
Later, news of polluted underground water in some provinces scared people who wondered whether the water they drink is safe.
So the need to emphasize environmental protection while developing the economy is heard everywhere.
Smog is especially a common concern. As a popular online post said, air may be the only thing that is equal for everyone, despite your income or profession. People with higher incomes are able to drink only bottled spring water and eat only organic food by paying higher prices, but they breathe the same air as everyone else.
At a meeting on Monday, many representatives have expressed their concerns about the air quality, too. One talked about his experience in Beijing. “After taking a taxi from the capital airport to my hotel, which took about an hour, I washed my nose and found the inside of my nose was black. We should ask ourselves this question: Why do we want to develop? It's for living a better life. Dirty air is definitely not a better life，” he said.
China needs to develop its economy and invest (投资) in hightech. Every Chinese has a dream to make China stronger. But without blue sky, clean water and safe food, the achievements in the economy will become meaningless. Space technologies are not to be developed for building a base on Mars so that one day all human beings can move to the red planet because they have destroyed Earth.
What the public wants is a strong and beautiful China. The great efforts must be made to promote ecological progress and build a beautiful China. The words have shown the central government's determination to address the environment issue.The effect of smog doesn't include ________.
| A．the rising of PM2.5 readings |
| B．more people suffering diseases |
| C．the increase of people's income |
| D．patients increased in hospital |
Why has smog become a common concern?
| A．Because people have to pay higher prices. |
| B．Because nobody can avoid it. |
| C．Because we have to develop industry. |
| D．Because a popular onlinepost discussed it. |
To make China stronger we have to develop economy, but ________.
| A．we have to sacrifice air as the price |
| B．the dirty air is not what we want |
| C．ecological progress can be ignored |
| D．the smog is the only byproduct |
From the last two paragraphs we can infer that ________.
| A．hightech can completely solve the problem of pollution |
| B．space technologies should be developed in a large scale |
| C．we can move to Mars after the earth has been destroyed |
| D．we must protect the environment while developing economy |
As the richest country in the world, you'd expect that Qatar would also be the happiest. And you'd also expect Japanese people to be extremely positive, seeing as though they have the highest life expectancy. But clearly wealth and good health do not guarantee happiness after both countries failed to make the top ten most positive countries.
The poll (民意测验 ) of nearly 150,000 people around the world found that seven of the world's 10 countries with the most upbeat attitudes are in Latin America. Gallup asked about 1,000 people in each of 148 countries if they were wellrested, had been treated with respect, smiled or laughed a lot, learned or did something interesting and felt feelings of enjoyment the previous day.
In Panama and Paraguay, 85 percent of those polled said yes to all five, putting those countries at the top of the list. They were followed closely by El Salvador, Venezuela, Trinidad and Tobago, Thailand, Guatemala, the Philippines, Ecuador and Costa Rica.
The people least likely to report positive emotions lived in Singapore, the wealthy and orderly citystate that ranks among the most developed in the world. Other wealthy countries also sat surprisingly low on the list. Germany and France tied with the poor African state of Somaliland for 47th place.
Many of the seven countries which were most positive do poorly in traditional measures of wellbeing, like Guatemala, a country torn by decades of civil war followed by waves of gangdriven criminality that give it one of the highest killing rates in the world. Guatemala sits just above Iraq on the United Nations' Human Development Index, a composite of life expectancy, education and per capital income. But it ranks seventh in positive emotions.
In Guatemala, it's a culture of friendly people who are always smiling, said Luz Castillo, a 30yearold surfing instructor. Despite all the problems that we're facing, we're surrounded by natural beauty that lets us get away from it all.
The poll shows that prosperous nations can also be deeply unhappy ones. And povertystricken ones are often positive, or at least a close approximation (类似事物) of it.________ may feel the most unhappy according to the poll.
| A．People from Qatar | B．People from Thailand |
| C．People from Japan | D．People from Singapore |
The underlined word “Gallup” in Paragraph 2 refers to ________.
| A．a country | B．a polling organization |
| C．a person | D．a magazine |
Which of the following is NOT included in the United Nations' Human Development Index?
| A．Life expectancy. | B．Education. |
| C．Natural beauty. | D．Per capital income. |
What's the best title of the text?
| A．Happiness does not depend on wealth |
| B．How to live happily? |
| C．Health leads to happiness |
| D．What are the standards to be happy men? |
Anyone who has ever lost keys or money will have wished for a simple but effective way to make sure it never happens again. A US company is trying to help.
Using a tiny microchip which is implanted into the arm, they have come up with a replacement for cash or credit cards that cannot be left at home or dropped on the bus.
The Verichip is about the size of a grain of rice and works using radio frequency identification technology. At a shop, a radio frequency “reader” would send a signal and the chip in your arm would respond with your unique identity number. That would give the “reader” your financial information, and money could be taken directly from your accounts and you wouldn't even have to reach for your wallet.
The company also hopes to include other information on the chip, such as medical records, building security codes (密码) and passwords, making life even easier.
But not everyone is happy with the developments. Critics say that a lot can go wrong with the chip. A clever thief could build a fake (假的) reader that would steal your information without you knowing. So your money could still be stolen. Privacy is a big issue too. Stores, or even the government, only need to track the chip to find out what you buy, how much you spend and where you go.
And if you wanted to get rid of your chip, you would need an operation to remove it.The Verichip is ________.
| A．the identity number | B．the security code |
| C．a tiny microchip | D．a radio reader |
Which is true of the Verichip?
| A．Your information on it will always be safe. |
| B．Medical records have already been included. |
| C．You can easily reach for your wallet using it. |
| D．An operation has to be performed to remove it. |
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