Part of the fun of watching sports events is following an exciting rivalry (竞争关系).

    But where do all these rivalries come from?

    Some rivalries start because athletes spend a lot of time close to opponents (对手).

    Other rivalries get personal. Things that one rival says that are thought to be not respectful to the other can cause a rivalry, even if the words are misunderstood. And sometimes, rivalries grow just because the athletes don't like each other's personalities.

    Some sports may also be more likely than others to cause rivalries. “Some sports only meet a few times, so there is less chance for rivalries to build,” For example, in sports where athletes perform on their own, such as diving, rivalries might also take longer to appear than in sports in which athletes compete at the same time. But in tennis, players often face each other, and rivalries are more likely to happen.

    So do the rivalries do good or harm to the athletes?

    Some believe that rivalries can be a good thing because they encourage athletes to try harder to win. But rivalries can also become too personal, taking athletes' attention away from their sports.

    Keegan agreed that rivalries often do athletes more harm than good. “They can be a huge distraction (分散注意力的事) and lead to focusing on the opponent more than the game,” he said.

    “Top athletes often have physical and mental training that they follow in order to worry less and prepare to compete”, Gould further explained. An important part of that preparation is preventing from distractions, including rivalries.

    “The better athletes don't care too much about a rivalry – they try to treat every competition the same,” Gould told LiveScience.

    Many foreign students report feeling lonely or unwelcome in Australia. Those feelings are among the reasons why Australia is taking a close look at its international education industry. But wherever international students go, making friends may not always be easy. Elisabeth Gareis of Baruch College in New York surveyed 454 international students. They were attending four-year colleges and graduate schools in the American South and Northeast.

    Students from English-speaking countries and from northern and central Europe were more likely to be happy with their friendships. But 38% of the international students said they had no close friends in the United States. And half of the students from East Asia said they were unhappy with the number of American friends they had. Thirty percent said they wished their friendships could be deeper and more meaningful.

    Professor Gareis says, “Students from East Asia have cultures that are different on many levels from the culture in the United States. There are also language problems, and maybe some social skills, such as small talk, which are possibly not as important in their native countries, where it's not as important to start friendships with small talks. Many East Asian students blamed themselves for their limited friendships with Americans, for not speaking the language well enough and for not knowing the culture well enough.

    VOA's Student Union blogger Jessica Stahl did her own survey to find out how American students and foreign students relate to each other. More than 100 students, about half of them American, answered her online questions.

Half of the international students and 60% of the Americans said they related as well or better to the other group than to their own group.

    Professor Gareis says: "International students who make friends with host nationals are, overall, more satisfied with their stay in the host country. They have better language skills, they have better academic performance and they have better attitudes toward the host country."

    Tiny as they are, bats have the ability to “see” in the dark by using a special skill called echolocation(回声定位法). They make noises and wait for sound waves, or an echo, to bounce(反弹) back off objects. They can tell the distance of various objects by how quickly the sound waves bounce back off them. If no sound bounces back, they can then fly forward.

    This special ability has been simulated in the human world for a long time, such as in submarines and planes, whose sonar(声呐) systems are somewhat similar to echolocation. But apart from helping vehicles “see” where they are, what if blind people could use echolocation for themselves? It turns out, some already are.

    American Daniel Kish, who is blind, is known as “Batman”. This isn't because he walks around in a cape and a mask, but because he has a bat-like ability to locate where he is through sharp clicks he makes by moving his tongue against the roof of his mouth. Kish is so skilled at echolocating that he can ride a bike and hike on his own.

    Recently, research carried out at the University of Durham in England shed some light on the power of human echolocation.

    Kish worked with a group of scientists who studied the way blind people listen to the echoes that they produce from clicks.

    The team, which conducted experiments with other volunteers, found that people were capable of hearing even very faint echoes, ones far fainter than had been previously thought.

    Speaking to The Independent, Lore Thaler, lead scientist of the group, said, “We found that in some conditions, they were really faint – about 95 percent softer than the actual clicks, but the echolocators were still able to sense this.”

    Andrew Kolarik of the University of Cambridge is another expert in echolocation. Reacting to the Durham study, he told BBC News that echolocation “can be very useful at providing information at face or chest height” and could help people “avoid objects like low hanging branches that might not get detected by the cane or a guide dog”.

    Although Kish's skill is remarkable, there's hope for other blind people who want to use echolocation. According to BBC News, echolocation is a skill blind people can acquire and develop, just like learning a language. As Kolarik said: “Teaching echolocation skills could provide blind people with the means of exploring new places.”

    When introducing American universities, some of the first institutions to mention are the Ivy League schools. Originally, the Ivy League was an athletic conference made up of 8 private institutes of higher learning in northeastern United States. However, as time went on, these schools also became known for their excellence in academics besides athletics. Included in the Ivy League schools are Brown University, Columbia University, Cornell University, Dartmouth College, Princeton University, University of Pennsylvania, Yale University, and Harvard University. These 8 schools have been recognized as some of the best colleges and universities in the United States.

    Harvard University is a private institution located in Cambridge, Massachusetts. The university includes a number of graduate and professional schools, as well as a college for undergraduates. In 2012, Harvard ranked number one in US News' ranking of national universities again. Founded in 1636, Harvard is the oldest institute of higher education in the United States. It can be said that first there was Harvard, then the United States of America. Also, Harvard's library contains the oldest collection of books in the United States as well as the largest private collection in the world. Harvard has also been described by Forbes Magazine as one of the "billionaire universities" as of their recent list of 469 billionaires, 50 received a degree from Harvard.

    Harvard College (the institute for undergraduate students) is one of the most famous schools in the United States. It offers over 40 undergraduate fields of study, including astrophysics(天体物理学), mathematics, neurobiology(神经生物学), etc. And the financial aid program there is amazing. Even though the tuition is about $ 37,576, and there are other expenses throughout the year, about 70% of undergraduate students received financial aid. Out of those students, over 90% of them had their full need met. And the policies for international students are the same for U.S. citizens.

    Harvard College is very selective, as it only admits about 6% of their applicants. For admission into Harvard College, it is required that students take the SAT or the ACT, as well as SAT Subject Tests. Harvard will also look at other factors during admission such as your application essay, high school transcript, work experience, GPA (Grade Point Average), your interview, recommendations, and most importantly, your character and personal qualities.

    HOLLAND & BARRETT

    Valerian capsules(缬草胶囊)

    A traditional herbal medicinal product used for the temporary relief of symptoms of mild anxiety and to aid sleep. This is based on traditional use only.

    Active Ingredients:

    Each capsule contains 337mg of extract (as dry extract) from Valerian root (Valerian officinalis L) (equivalent to 1683mg-2020mg of Valerian root).

    Dosage（剂量）:

    For oral use only.

    For adults and elderly:

    Mild anxiety — Take 1 capsule 3 times daily.

    To aid sleep — Take 1 capsule 30 minutes to 1 hour before bedtime with an earlier dose during the evening if necessary.

    Swallow the capsule with water. As the effects of this product may not occur immediately, the capsule should be taken continuously for 2-4 weeks.

    The maximum dose is 4 capsules per day.

    Duration of use: If symptoms worsen or do not improve after 4 weeks, a doctor or a qualified healthcare practitioner should be consulted.

    Warnings:

    Do not exceed (超过) the stated dose.

    Do not take this product if you are:

    Under 18 years of age

    Pregnant or breastfeeding

    Allergic to Valerian or any of the excipients (辅药)in this product

    Already taking a medicine for sleep or anxiety

    Storage: Store the capsules below 25℃.

    Keep the bottle tightly closed.

    Keep out of sight and reach of children.

    Registration Holder:  NBTY Europe Limited, Samuel Ryder House, Barling Way, Nuneaton, Warwickshire, CV10 7RH, United Kingdom

    Vaping can be just as damaging to your health as smoking. But the minute you kick the habit, you'll feel a difference.

    Vaping is the use of electronic cigarettes-e-cigarettes. Vaping became mainstream in the United States in the late 2000s. When e-cigarettes first hit the market, people believed they were a safer choice to tobacco cigarettes. We now know, however, that vaping, like smoking cigarettes can be quite damaging to your health-and equally addictive.

    Kids and teenagers are especially attracted to vaping, thanks to attractive flavors. Vape use in high school students rose by 900 percent between 2011 and 2015.

    Quitting vaping can be difficult, just like trying to stop smoking. There are some immediate, though often temporary, negative effects. The positive ones soon outpace the negative, however.

    In as little as 20 minutes, your heart rate returns to normal, your blood pressure drops, and your circulation starts to normalize. Your breathing may improve, too.

    Daily e-cigarette doubles a person's risk for a heart attack. If you quit, however, the risk begins to fall very quickly. Also, vaping, like cigarette smoking, can blunt your senses, reducing your ability to smell and taste. After just 48 hours without vaping, you may begin to notice your ability to taste and smell food has improved. Nicotine affects more than your brain: new research suggests nicotine can raise your blood sugar, too.

    Smokers often have a troublesome cough or make a breathless sound when they breathe that many refer to as a smokers cough. Smoking even e-cigarettes can badly harm your lung health and make fighting off infections difficult. Quitting, however, will help your lungs recover. After one month, your lung capacity improves.

    There will come a day when the bad habit of vaping won't have any lasting influence on your body and your health.