Conventional wisdom says that hardship can make us old before our time. In fact, a new study suggests that violence not only leaves long-term scars on childrens bodies, but also changes their DNA, causing changes that are equal to seven to ten years of premature aging.
Scientists measured this by studying the ends of childrens chromosomes(染色体), called telomeres, says Idan Shalev, lead author of a study published in Molecular Psychiatry.
Telomeres are special DNA sequences which prevent the DNA in chromosomes from separating. They get shorter each time a cell divides, until a cell cannot divide any more and dies.
Several factors have been found to shorten telomeres, including smoking, radiation and psychological stresses such as being treated badly when young and taking care of a chronically ill person.
In this study, researchers examined whether exposure to violence could make children’s telomeres shorten faster than normal. They interviewed the mothers of 236 children at ages 5, 7 and 10, asking whether the youngsters had been exposed to domestic violence between the mother and her partner; physical maltreatment by an adult; or bullying. Researchers measured the children’s telomeres—in cells obtained by swabbing the insides of their cheeks—at ages 5 and 10.
Telomeres shortened faster in kids exposed to two or more types of violence, says Shalev. Unless that pattern changes, the study suggests, these kids could be expected to develop diseases of aging, such as heart attacks or memory loss, seven to 10 years earlier than their peers.
Shalev says there is hope for these kids. His study found that, in rare cases, telomeres can lengthen. Better nutrition, exercise and stress reduction are three things that may be able to lengthen telomeres, he says.
The study confirms a small but growing number of studies suggesting that early childhood adversity imprints itself in our chromosomes, says Charles Nelson, a professor of pediatrics and neuroscience at Harvard Medical School.The new study found that ________.
| A．hardship can change a childs aging |
| B．violence leaves scars on a childs mind |
| C．violence can speed up a childs aging |
| D．hardship has a long term effect on a childs mind |
According to the text, telomeres ________.
| A．are at the ends of peoples chromosomes |
| B．can help prevent DNA from separating |
| C．can make a cell die quickly |
| D．become shorter before they die |
Which of the following is TRUE according to the text?
| A．Violence can cause quick cell division in childrens body. |
| B．Researchers measured the childrens telomeres from their legs in the study. |
| C．Being treated badly will make a childs telomeres shorten faster. |
| D．Children who have shorter telomeres may have a heart attack earlier. |
What is the best title for the text?
| A．Violence Aging Childrens DNA |
| B．Childrens Changing DNA Patterns |
| C．Violence and Telomeres |
| D．The Function of Telomeres |
“Soon, you’re going to have to move out!” cried my neighbor upon seeing the largest tomato plant known to mankind, or at least known in my neighborhood.
One tiny 9-inch plant, bought for $1.25 in the spring, has already taken over much of my rose bed, covering much of other plants, and is well on its way to the front door.
Roses require a good deal of care, and if it weren’t for the pleasure they give, it wouldn’t be worth the work. As it is, I have a garden full of sweet-smelling roses for most of the year. Bushes must be pruned(剪枝) in early spring, leaving ugly woody branches until the new growth appears a few weeks later. It was the space available in the garden that led me into planting just one little tomato plant. A big mistake.
Soil conditions made just perfect for roses turn out to be even more perfect for tomatoes. The daily watering coupled with full sun and regular fertilizing(施肥) have turned the little plant into a tall bush. The cage I placed around it as the plant grew has long since disappeared under the thick leaves.
Now the task I face in harvesting the fruit is two fold(方面): First, I have to find the red ones among the leaves, which means I almost have to stand on my head, and once found I have to reach down and under, pick the tomatoes and withdraw my full fist without dropping the prize so dearly won. Second, I found two full-blown white roses completely hidden as I picked tomatoes in June, but they were weak and the leaves already yellow for lack of light.
Here I am faced with a painful small decision: To tear up a wonderful and productive tomato plant that offers up between ten and twenty ripe sweet tomatoes each day or say goodbye to several expensive and treasured roses. Like Scarlett in Gone With the Wind, I’ll think about that tomorrow.What are the requirements for the healthy growth of roses?
| A．Frequent pruning and fertilizing. |
| B．Tomato plants grown alongside. |
| C．Cages placed around the roots. |
| D．A lot of care and the right soil. |
The writer planted the tomato because ____.
| A．there was room for it in the garden |
| B．it cost only $1. 25 |
| C．the soil was just right for i |
| D．the roses’ branches needed to be covered |
This year the writer’s roses were ____.
| A．removed from the rose bed |
| B．picked along with the tomatoes |
| C．largely hidden under the tomato plant |
| D．mostly damaged by too much sunlight |
By saying “the prize so dearly won” in paragraph 5, the writer wants to ____.
| A．show the hardship of growing the roses |
| B．show the difficulty in picking the tomatoes |
| C．express her liking for the roses |
| D．express her care for the tomatoes |
Unlike chemists and physicists, who usually do their experiments using machines, biologists and medical researchers have to use living things like rats. But there are three Nobel prize-winning scientists who actually chose to experiment on themselves – all in the name of science, reported The Telegraph.
● Werner Forssmann (Nobel prize winner in 1956)
Forssmann was a German scientist. He studied how to put a pipe inside the heart to measure the pressure inside and decide whether a patient needs surgery (手术).
Experiments had been done on horses before, so he wanted to try with human patients. But it was not permitted because the experiment was considered too dangerous.
Not giving up, Forssmann decided to experiment on himself. He anaesthetized (麻醉) his own arm and made a cut, putting the pipe 30 centimeters into his vein (血管). He then climbed two floors to the X-ray room before pushing the pipe all the way into his heart.
● Barry Marshall (Nobel prize winner in 2005)
Most doctors in the mid-20th century believed that gastritis was down to stress, spicy food or an unusually large amount of stomach acid (胃酸). But in 1979 an Australian scientist named Robin Warren found that the disease might be related to a bacteria (细菌) called Helicobacter pylori. So he teamed up with his colleague, Barry Marshall, to continue the study. When their request to experiment on patients was denied, Marshall bravely drank some of the bacteria. Five days later, he lost his appetite and soon was vomiting (呕吐) each morning – he indeed had gastritis.
● Ralph Steinman (Nobel prize winner in 2011)
This Canadian scientist discovered a new type of immune system cell (免疫细胞) called the dendritic cell. He believed that it had the ability to fight against cancer.
Steinman knew he couldn’t yet use his method to treat patients. So in 2007, when doctors told him that he had cancer and that it was unlikely for him to live longer than a year, he saw an opportunity.
With the help of his colleagues, he gave himself three different vaccines (疫苗) based on his research and a total of eight experimental therapies (疗法). Even though Steinman eventually died from his cancer, he lived four and a half years, much longer than doctors had said he would.The main purpose of the article is to ______.
| A．list some famous Nobel prize winners. |
| B．introduce a few Nobel prize winners who did experiments on themselves. |
| C．describe some dangerous experiments that Nobel prize-winners did on themselves. |
| D．list some difficulties that scientists go through to make important discoveries in biology . |
Which of the following is TRUE according to the article?
| A．Forssmann’s experiment ended in failure. |
| B．Forssmann had the pipe pushed all the way into his heart. |
| C．Barry Marshall succeeded by drinking some Helicobacter pylori. |
| D．Barry Marshall was given full responsibility for the study on gastritis at first. |
The underlined word “gastritis” in Paragraph 5 probably means ______.
| A．a kind of stomach disease | B．a kind of immune cell |
| C．a new type of therapy | D．a type of leg cancer |
From the text, we can conclude that Ralph Steinman ______.
| A．had his request to experiment on patients denied |
| B．believed that cancer comes from stress and spicy food |
| C．discovered a new type of cancer cell called the dendritic cell |
| D．tried different therapies containing the dendritic cell on himself |
Someday a stranger will read your email without your permission or scan the websites you've visited. Or perhaps someone will casually glance through your credit card purchases or cell phone bills to find out your shopping preferences or calling habits.
In fact, it's likely some of these things have already happened to you. Who would watch you without your permission? It might be a girlfriend, a marketing company, a boss, a policeman or a criminal. Whoever it is, they will see you in a way you never intended to be seen—the 21st century equal to being caught naked.
Psychologists tell us boundaries are healthy, though it's important to reveal yourself to friends, family and lovers in stages, at appropriate times. Actually few boundaries remain. The digital bread crumbs you leave everywhere make it easy for strangers to reconstruct who you are, where you are and what you like. In some cases, a simple Google search can reveal what you think. Like it or not, increasingly we live in a world where you simply cannot keep a secret.
The key question is: Does that matter? For many Americans, the answer apparently is “no”.
When opinion polls ask Americans about privacy, most say they are concerned about losing it. A survey found a majority of people are pessimistic about privacy, with 60 percent of respondents saying they feel their privacy is “slipping away, and that bothers me”．
But people say one thing and do another. Only a small part of Americans change any behaviors in an effort to preserve their privacy. Few people turn down a discount at tollbooths to avoid using the EZPass system that can track automobile movements. And few turn down supermarket loyalty cards. Privacy economist Alessandro Acquits has run a series of tests that reveal people will submit personal information like Social Security numbers just to get their hands on a pitiful 50centsoff coupon(优惠券).
But privacy does matter at least sometimes. It's like health: when you have it, you don't notice it. Only when it's gone do you wish you'd done more to protect it.From Paragraph 2, we can infer________.
| A．criminals are easily caught on the spot with advanced technology |
| B．people tend to be more frank with each other in the information age |
| C．in the 21st century people try every means to look into others' secrets |
| D．people's personal information is easily accessed without their knowledge |
What would psychologists advise on the relationships between friends?
| A．There should be a distance even between friends. |
| B．There should be fewer quarrels between friends. |
| C．Friends should always be faithful to each other. |
| D．Friends should open their hearts to each other. |
According to the passage, privacy is like health in that________.
| A．its importance is rarely understood |
| B．it is something that can easily be lost |
| C．people will make every effort to keep it |
| D．people don't treasure it until they lose it |
Bamboo (竹子) is one of nature’s (自然) most surprising plants. Many people call this plant a tree, but it is a kind of grass.
Like other kinds of grass, a bamboo plant may be cut very low to the ground, but it will grow back very quickly. A Japanese scientist reported one bamboo plant which grew 1.5 metres (4 feet) in 24 hours! Bamboo grows almost everywhere in the world except Europe. There are more than 1, 000 kinds of bamboo.
Not all bamboo looks the same. Some bamboo plants are very thin. They may only grow to be a few centimeters wide while others may grow to more than 30 centimetres (1 foot) across. This plant also comes in different colors, from yellow to black to green.
Bamboo has been used to make many things such as hats and kitchen tools. Because it is strong, bamboo is also used to build buildings.
Many Asian countries have used bamboo for hundreds of years. They often use bamboo for buildings and supporting new buildings and bridges while they are being built.
In Africa, poor farmers are taught how to find water using bamboo. These African countries need cheap way to find water because they have no money, and their crops often die from no rain and no water. Bamboo pipes help poor farmers bring water to their thirsty fields without spending a lot of money. How is bamboo like grass?
| A．It grows quickly. | B．It’s wood. |
| C．It is easy to cut | D．It is very thin |
Though you can see bamboo everywhere, it doesn’t grow ______.
| A．in China | B．in Europe |
| C．on mountains | D．in Africa |
Why is bamboo used by African poor farmers?
| A．Because it is cheap. |
| B．Because it has different colours . |
| C．Because it is strong. |
| D．Because it has been used by Asians. |
Bamboo pipes can ______.
| A．make money | B．be trees |
| C．grow quickly | D．carry water |
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The oceanfront accommodations at Beach Plaza Hotel are some of the most affordable on Fort Lauderdale Beach．Each room features direct-dial telephone, cable television and daily maid service．The very affordable efficiency studios even include full kitchens! All rooms surround the private poolside garden courtyard．
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Guest rooms feature TVs, in-room movies, Internet access, in-room safes, alarm clock radios, hairdryers, refrigerators, microwaves, and balconies．
Check-in Time：7:00 A.M.
Hotel Amenities：Parking，Heated Pool, Television with Cable, and Coffee Maker in Room．Which hotel gives a promise?
| A．Beach Plaza Hotel． | B．Baymont Inn Ft . Lauderdale． |
| C．Baymont Inn Hotel． | D．Fort Lauderdale Plaza Hotel． |
In which hotel parking is the cheapest?
| A．Beach Plaza Hotel． | B．Baymont Inn Ft . Lauderdale． |
| C．Baymont Inn Hotel． | D．Fort Lauderdale Plaza Hotel． |
If you ______ , you will probably go to Beach Plaza Hotel．
| A．enjoy seeing films without leaving your hotel room |
| B．want to eat food cooked by yourself in the hotel |
| C．are fond of swimming in heated water |
| D．are a cigarette smoker |
Which of the following is NOT true to the ads?
| A．In Beach Plaza Hotel a 24-hour maid is available． |
| B．All of the three hotels provide television with cable． |
| C．You can keep your money in the room safe in Fort Lauderdale Plaza Hotel． |
| D．While staying in Fort Lauderdale Plaza Hotel, you can surf the Internet． |
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