Fighting racial stereotypes（模式化）on US campuses often begins by putting students of different ethnic backgrounds together — under one dormitory roof.

    Sam Boakye was a freshman at Ohio State University and the only black student on his floor. He was determined to get good grades — in part to make sure his white roommate had no basis for negative racial views. "You're pushed to do better, to challenge the stereotype that black people are not that smart," he told the New York Times.

    Several recent studies have found that having a roommate of a different race can reduce prejudice(偏见), diversify(使多样化) friendships and even promote students' academic performance. In a study by Ohio State psychology professor Russell Fazio, black freshmen who came to college with high test scores earned better grades if they had a white roommate—even if the roommate's test scores were low. Another study on student interaction by Duke University suggests that freshmen with roommates of a different race were the most likely to diversif“y their friendships. Just having diversity in classrooms doesn't do anything to increase interracial friendships," said Claudia Buchman, an author of the Duke study. “But living together with a different-race roommate does lead to more interracial friendships."

    There are, however, some problems with such room assignments. Fazio's study found that three times as many randomly(随机地) assigned interracial roommates weren't living together at the end of the semester, compared with white roommates. Interracial roommates also spent less time together, had fewer joint activities and were less involved with each other's friends than white pairs.

    As for Boakye, this is not the case. "A lot of white students come without much exposure（暴露）to diversity, so when their first interaction with a black guy isn't bad, they will make more black friends. I think I made a good impression on my freshman roommate. I saw him this year, and he said, "Hey dude, you're not the only black friend I have. That felt good."

    Sleep is something we all do. But some people need to sleep more than others. Babies sleep most of the time. Children in school sleep about ten to twelve hours a night. Most adults sleep only seven or eight hours. {#blank#}1{#/blank#}

    All parts of our bodies have to rest after they work.. Our arms need a rest after we lift heavy thing, When we run fast, our legs work hard. They get tired. We have to rest them. Our brains work hard, too. {#blank#}2{#/blank#}. We can sit quite still and rest our arms and legs. But our brains aren't resting. They go right on thinking as long as we are awake.

    Our brains slow down a bit when we sleep and dream. {#blank#}3{#/blank#} Instead of thinking wide-awake thoughts, our brains make up dreams. Some dreams are very pleasing. Some are not. Most of the time we forget them when we wake up.

    Scientists have tried to find out what would happen if people were not allowed to sleep. They asked some people not to go to bed. The people stayed up all night and all the next day. They stayed up the next night too, and the day after. They played games, but they made mistakes. They forgot things. {#blank#}4{#/blank#}

    The people grew rude and mean. They became angry with their friends. Finally they were too tired to stand up. When they sat down, they fell asleep.

    Scientists have found that if people are not allowed to sleep and to dream, they act in an unusual way. {#blank#}5{#/blank#} But we do know that we need it to stay well. So tonight have a good sleep. Lie down under the covers. Shut your eyes. Let your thoughts wander. Soon you'll stop thinking. You'll be asleep.

A. It was hard for their tired brains to work.

B. When we are awake, they help us pay attention to the world around us.

C. But babies, children, and adults — all of us need to have our sleep.

D. Good sleep helps to improve one's memory.

E. No one knows why sleep is so good for us.

F. But even as we sleep our brains are doing some work.

G. Of course you will have a good sleep.

    Jealousy is such a powerful emotion that at least one study has characterized it as the third leading cause of non-accidental homicide(杀人) in all cultures. In a recently published study, researchers experimented with dogs to see whether they, like humans, have the nature of jealousy.

In an experiment, the authors took 36 dogs—along with their owners—and observed the dogs' behavior as their masters interacted with three non-living objects. One object was a children's book, which they read aloud; another object was a plastic pumpkin lantern; and the third was a mechanical stuffed dog that gave out a bark when the owner pressed a button.

    Former studies concluded that babies were probably capable of jealousy. In the experiment, their mothers showed attention to a life-like doll instead of their child, and other objects. The babies were reportedly more likely to respond with “negative” behavior if their mother turned to pay her attention to the doll.

    In the dog experiment, authors instructed the dog owners to push the bark button on the stuffed dog's head, and then speak to it sweetly, while ignoring their own dog. After that, they showed attention to the pumpkin lantern, and read the children's book, while also ignoring their dog.

    It is interesting to see the dogs were far more likely to act aggressively when their owners spoke to the stuffed dog than when they paid attention to the other objects. One-fourth of the dogs snapped at the stuffed dog, while only one dog snapped at the lantern or the book. The dogs were also more likely to push or touch their owners as they interacted with the mechanical dogs, and tried to get in between the owner and the stuffed dog more frequently than the other objects.

    “One possibility is that jealousy developed in species of many young relying on the parents, the young compete for parental resources such as food, attention, care, and affection,” the authors wrote.

    Here's an idea whose time has come: A flu shot that doesn't require an actual shot.

    For the first time, researchers have tested a flu vaccine patch(疫苗贴) in a human clinical trial and found that it delivered as much protection as a traditional injection(注射) with a needle. Doctors and public health experts have high hopes that it will increase the number of people who get immunized(免疫的) against the flu.

    Seasonal flu is responsible for up to half a million deaths around the world each year according to the World Health Organization. A team led by Georgia Tech engineer Mark Prausnitz has come up with an alternative method that uses "microneedles". These tiny needles are so small that 100 of them, arranged in order on a patch, can fit under your finger. Yet they're big enough to hold vaccine for three types of flu.

    None of the study volunteers had serious side effects. The groups that got patches had mild skin reactions that were not seen in the regular needle group, while the volunteers in the regular needle group were more likely to experience pain. Overall, 70 percent of the volunteers who got vaccine patches said they'd rather use them again than get a traditional flu shot. The study authors declared it a success on all fronts.

    The biggest beneficiaries could be people in low and middle-income countries, where flu vaccines are hard to come by. Reducing pain is nice, but other benefits—the patch costs less, is easier to transport, doesn't require refrigeration, can be self-administered and doesn't cause waste of needles—are even better.

    "Microneedle Patches have the potential to become ideal candidates for vaccination programs," wrote Katja Hoschler and Maria Zambon of Public Health England.

    What happens inside the head of a soccer player who repeatedly heads a soccer ball. That question motivated a study of the brains of experienced players.

    Researchers at the Albert Einstein College of Medicine in New York selected 34 adults, men and women. All of the volunteers had played soccer since childhood and  now competed year﹣round in adult soccer leagues. Each filled out a detailed questionnaire developed especially for this study to determine how many times they had headed a soccer ball in the previous year, as well as whether they had experienced any known concussions in the past.

    Then the players completed computerized tests of their memory and other learning skills and had their brains scanned. using a complex new M.R.I. technique which can find structural changes in the brain that can't be seen during most scans.

    According to the data they presented, the researchers found that the  players who had headed the ball more than about 1, 100 times in the previous 12 months showed significant loss of white matter in parts of their brains involved with memory, attention and the processing of visual information, compared with players who had headed the ball less.

    This pattern of white matter loss is "similar to those seen in traumatic brain injury", like that after a serious concussion, the researchers reported, even though only one of these players was reported to have ever experienced a concussion.

    The players who had headed the ball about 1, 100 times or more in the past year were also generally worse at remembering lists of words read to them, forgetting the words far more often than players who had headed the ball less.

    Here's the bad news: Men are hurting, and, according to many researchers. masculinity (男子气) is what is hurting them and making it hard for them to maintain friendships. Society tells men to hide their feelings and expects them to be aggressive, so many men lose their friendship when growing up. The good news is that those skills can be recovered!

    There are a lot of experts who can help. and here's what they recommend:

    ⒈Accept your own desire and normalize it for the people in your life. Way, an expert, recommends sharing articles about masculinity and friendship so that you can start these conversations! Concentrate on them and don't forget you have the entire Internet at your fingertips, friend!

    ⒉Model vulnerability. Say the thing that frightens or worries you. like "I'm afraid nobody will go to my party," or "I miss my grandma every day." Doing so will make it easier for other people to follow your lead. We are all on the elevator to a society where emotional availability is normalized, and I want you to press "door open".

    ⒊Ask more questions. People sometimes feel they might be prying (爱打听的) if they ask someone about themselves-especially when their friend is sharing something tough. But if you get curious in moments of vulnerability you will open the door to all kinds of growth in your relationship. Take the opportunity to really see your friend and show them they matter by following up.

    ⒋Get close with the children in your life. Way's research says that the top priority that helps children (especially boys) grow up to have enriching friendships is to be close with an adult relative who was not afraid to express emotions. So. if you are a father. stepfather. or thinking about becoming one. or if you have nieces or nephews, take the opportunity to be close to them and help them grow up to be good friends, too.