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    University of South Carolina （USC) is famous for its warm southern hospitality（好客）. Schedule a visit and feel it in person. Our walking tours are led by current students, called University Ambassadors, who are looking forward to telling you what it's like to live and study in USC. Our walking tours run Monday through Friday and most are around 2 hours. The university will be closed on Tuesday, July 4, 2017 in observance of the holiday. We welcome your visit year round and will be ready for you, rain or shine. Please refer to the list below to determine which tour is best for you and remember to book at least two weeks in advance.

    Helen Monson has always been interested in helping her community. Her first volunteer experience was for the American Red Cross when she was in high school. When she was a school teacher, she also found time to volunteer.

After she retired, she started volunteering to help the old. When her father was older, he was not able to see as well as he used to, which made her sad because he had always enjoyed reading.

    She decided it would be fun to read to elderly people in her community. She also helped one woman write her stories. Ann was almost 100 years old, and Helen wrote down information about her life when she visited Ann. She put the information in a book and got it published. Ann was very excited to share her life story with her children and grandchildren.

    One day Helen read an article in the newspaper about refugees (难民) who needed to learn English. Now, she meets once a week with Sahra, a 38-year-old woman from Somalia. Sahra is learning reading and writing skills. Helen gave Sahra a camera and asked her to take pictures of her daily life. She developed the pictures, and then asked Sahra questions about them. In the end they wrote a book together and used the photos in the book. This helped Sahra learn many new words about her everyday life.

    Helen says, “The most rewarding part of volunteer work is becoming friends with the people I help. They enrich my life as well as I enrich theirs.”

    You know the feeling that you have left your phone at home and feel anxious, as if you have lost your connection to the world. “Nomophobia” (无手机恐惧症) affects teenagers and adults alike. You can even do an online test to see if you have it. Last week, researchers from Hong Kong warned that nomophobia is infecting everyone. Their study found that people who use their phones to store, share and access personal memories suffer most. When users were asked to describe how they felt about their phones, words such as “hurt” (neck pain was often reported) and “alone” predicted higher levels of nomophobia.

    “The findings of our study suggest that users regard smartphones as their extended selves and get attached to the devices,” said Dr. Kim Ki Joon. “People experience feelings of anxiety and unpleasantness when separated from their phones.” Meanwhile, an American study shows that smartphone separation can lead to an increase in heart rate and blood pressure.

    So can being without your phone really give you separation anxiety? Professor Mark Griffiths, psychologist and director of the International Gaming Research Unit at Nottingham Trent University, says it is what is on the phone that counts-the social networking that creates Fomo (fear of missing out).

    “We are talking about an internet-connected device that allows people to deal with lots of aspects of their lives,” says Griffiths. “You would have to surgically remove a phone from a teenager because their whole life is rooted in this device.”

Griffiths thinks attachment theory, where we develop emotional dependency on the phone because it holds details of our lives, is a small part of nomophobia. For “screenagers”, it is Fomo that creates the most separation anxiety. If they can't see what's happening on Snapchat or Instagram, they become panic-stricken about not knowing what's going on socially. “But they adapt very quickly if you take them on holiday and there's no internet,” says Griffiths.

    My six-year-old son, Stephen, was in front of the TV and smiled. His favorite show was about to begin-a Phoenix Suns basketball game.

    "Ladies and gentlemen," the announcer's voice was heard, "here is your starting lineup (首发阵容)." The arena (球场) darkened and the lights flashed when the players ran into the court to sing their team song. Stephen clapped and danced around. My wife Lorrie and I laughed. Stephen had been performing this for months. "One day I'm going to take you to a game, son," I promised.

    About a year later, the construction company where I worked finished a project for a Suns player. One afternoon my boss called me. "The player has two extra tickets for tonight's game! Just pick them up at my office," he said. I picked up the tickets, but felt a little disappointed when I looked at the clock. Even if I had had a helicopter, we would never have gone to the arena in time for the player introductions. Stephen would miss his favorite part! I grabbed my key, got Stephen in my car and hit the road. "Lord," I prayed, "I'd love to see the joy on Stephen's face. Help us make it on time."

    When I drove, it began to rain heavily. Suddenly, lightning flashed right near the arena! I turned on the radio to listen to the game. The announcer said there'd been a power failure at America West Arena. Everyone was fine, but there would be a delay until they got everything running. Finally, I parked the car and we walked in hurriedly to take our seats. I hoped that we hadn't missed the introductions.

    The very moment we entered the arena, the lights darkened. The music started. "Ladies and gentlemen, here's your starting lineup!" Stephen's eyes grew wide. There wasn't enough space for him to dance around, but I could tell that his heart was leaping more than his body was able to. Thank heaven, he hadn't missed a thing. And neither had I.

    American and British people both speak English of course. But sometimes it does not seem like the same language. In fact, there are some important differences between British English and American English.

    First of all, they sound very different. Often, Americans don't say each word separately. They say several words together. Americans may say "I dunno" instead of "I don't know". Or they may say "Whaddaya say?" instead of "What do you say?" However, the British are more careful in their speech. They usually say all the words and keep them separate.

    Sound is not the only difference between British English and American English. Words sometimes have different meanings too. Some American words are never used in England. The same thing is true of some British words in America. For example, the vocabulary for cars and driving is very different. Americans drive trucks, but in England people drive lorries.

    Many expressions are also different in the two countries. In England，if you are going to telephone your friends, you "phone them up". In America, you "give them a call". When you are saying goodbye in England you might say "Cheerio!" In America you might say "See you later."

    There're also some differences in grammar. For example, Americans usually use the helping verb "do" when they ask a question. They say "Do you have a storybook?" But the British often leave out the helping verb. They say "Have you a storybook?"

    All these differences can be confusing if you are learning English. But most languages are like this. Languages change over time. When people live in separate places, the languages change in different ways. This is what has happened to English. It can also happen to other languages, such as French. Many people in Canada speak French, but their French is very different from the French of France.

A seismic (地震的；重大的) shift in climate science might be heating up.

New research shows that sound waves, produced by earthquakes can be used to measure temperatures in the ocean which traps 90% of the heat Earth absorbs from the sun，making long-term changes in ocean warmth, a major factor in how the world might respond to global warming.

For years the main approach of measuring ocean temperature has been Argo, an array (阵列) of 4000 automatic floats, which drifts the globe, sampling ocean water and measuring its temperature. Yet Argo measurements stop at 2000 meters.

The new technique called "Seismic Ocean Thermometry", would be especially useful in detecting long-term changes in ocean temperatures deeper than Argo's reach.

"Ocean Acoustic Tomography", the basis for the current research, was first tested nearly 30 years ago. The initial studies created sound waves artificially, basically increasing the volume on giant underwater speakers. Scientists measured the sound's travel time from the speakers to receivers thousands of kilometers away. Because ocean temperatures affect the speed of the waves, the researchers could calculate average temperatures along their paths. But some believed the noise was a threat to ocean life and the technique never took off.

The new study instead uses a natural sound source for investigation: earthquakes making a low, continuous noise beneath the seafloor off the coast of Sumatra that drum up sound waves in the ocean. On the shores of the Chagos Islands in the East Indian Ocean, between 2005 and 2016 Seismic Station Diego Garcia recorded seismic waves produced by those earthquakes. Some of those waves created physical changes in land and sea as they traveled. Others were sound waves or T waves that moved through the deep ocean, delivering valuable data about ocean temperature.

12 years of data coupled with mathematical models pointed to a temperature change of roughly 0.044 degrees per decade, a trend larger than those predicted by Argo. The findings suggest that Seismic Ocean Thermometry is a feasible method to measure changes in ocean temperature. Further data from other regions of the globe and other timeframes would help improve the warning models and predictions.

And in future studies the researchers plan to listen directly for sound waves, using a network of hydrophones, microphones which detect sound waves under water. Sound waves set the tone for a deep dive into our warming oceans even if they fail to reach 60000 miles under the sea?