YOUR mom might cook a bowl of noodles for you on your birthday. But in the US, a mom makes a cupcake for her children on their birthday.

    Cupcakes are small, round cakes topped with frosting (糖霜). It has been an American tradition that moms bring cupcakes to the classroom to celebrate their child's birthday. But recently some doctors have called for this to be banned. They believe cupcakes contribute to child obesity. Despite their good intentions, however, some people believe that experts are interfering (妨碍) with American culture. The cupcake is seen as American as apple pie — only prettier.

    According to Marion Nestle, a professor of nutrition at New York University, the cupcake is the most democratic (民主的) of desserts. As they are small enough for one person, you don't have to share your cupcake with anyone — it's all yours. They are also all of the same size, so there can't be any cries of  “she got the bigger piece!”

    Each bite can taste different depending on how much icing you have. It is a lesson in self-determination. Some people eat only a little of the frosting every time, others have it all in just one bite.

    In recent years, eating a cupcake has become as trendy as having a cup of Starbucks coffee.

    Democratic presidential candidate Hillary Clinton jokingly promised on a talk show that if she was elected president, she would give everyone a cupcake on her birthday. Ruth Reichl, editor-in-chief of Gourmet magazine, explains that the rise of the cupcake is very much about going back to American national identity in food, which is all about comfort. “People want to think about when they and their country were innocent,” she said.

    When the population of the port town began to suffer from poisoning, the police came to find the cause of the poison. They thought someone was poisoning the people on purpose but no one knew how it was possible. Soon people took the position that the pork was poisoned. It was a popular food everyone ate and it could have possibly made everyone sick. Anyone who had possession of pork would throw it out. Even the poorest of the poor wouldn't eat pork. Signs were posted on poles and letters were sent to everyone to warn people of the pork. Shortly afterwards, even policemen in high positions were also getting sick.

    Soon it became political and popular. Politicians rushed to the town to talk about politics and promised how they would find the solution if they were elected. Everyone was so sick that they didn't care about politics. Everyone was in a position where he or she didn't know what to do anymore. They went to the post office to mail posts out asking for help. The poor town didn't know how to deal with the situation.

    One day, a well-known scientist from New York came to the town with a huge box containing many instruments and his possessions. He went to pools and the port and made measurements. He was quiet and polite. Then one day he made a speech at a newspaper meeting-room to announce his findings.

    “I'm sorry to say your water supply is so heavily polluted; it is poisoned. I know who has been poisoning you all for such a long time. It is you who have been poisoning yourselves with pollution. A great deal of rubbish has been thrown into the water day after day. No one here has taken good care of the environment. It is no wonder all of you have been sick.” Shocked at the news, the people present were lost in thought.

    Climate change has had a number of effects on cities around the world, including rising see levels. And, this has become an especially big problem for coastal cities. City officials must now prepare for higher tides on their coasts. The American city of Miami is one example. Located in South Florida, Miami is home to nearly 3 million people and billions of dollars in land and buildings.

    Miami is one of the cities in America most at risk for rising sea levels. The waterfront is central to Miami's culture and economy. But as the seas rise with climate change .the water will not stay put. Large parts of South Florida are in danger of being under water in the coming years. Across Biscayne Bay, the City of Miami Beach is making improvements - raising streets, adding water pumps and more.

    It is costing the city a lot of money. Local communities will spend 500 million dollars for the improvements. Thankfully, the residents, the folks that are paying the bill for this work, realize that the cost of doing nothing is much greater. A possibility officials are discussing with residents is for city to buy homes in some places where flooding has been a problem. The city would then turn that land into parks of grassland that could hold the water.

    Over time, the city may need to take bigger risks. Miami's future depends largely on how much, and how fast, the oceans rise.

    Caroline Lewis leads the climate activism group, the CLEO Institute. She says cities cannot avoid the need to move inland. But, she says，a well-planned withdrawal (撤退) could include measures to keep people safely in place for as long as possible. And, she says, the world could learn from such a model. In these two Florida cities built on wetlands, there remains a lot of hopefulness.

    One side effect of globalization and the related phenomenon of greatly increased mobility is that the traditional definition of “foreigner” has passed its sell-by date.

    Is a European who has lived in China longer than in his home country, becoming fluent in the language and culture in the process, still a foreigner in China, or has he become more of a foreigner in his own home town? What about a Beijinger who did her schooling in Canada and then lived and worked in mainstream society there for another 20 years while raising a family, who has no intention of returning to China? Does she think and act like a foreigner? What do we mean by this label(标签)?

    When I grew up in the suburbs of Chicago, the faces you would see during a walk through a local shopping mall back in the 1960s and 1970s included almost none of Asian descent. Today the same malls are full of Asian faces, and a glance at the ranks of top scoring students in local schools reveals lots of Asian surnames.

    To some extent, this is no great surprise in the American context, because America is a land of immigrants, and a cultural melting pot. Apart from the native American Indians, Americans are (or were), in some way, all foreigners anyway. Absorbing a large number of immigrants is an established pattern in American history.

    In most places, the traditional foreigners were people who didn't speak or read the local languages well, were unfamiliar with local customs and lifestyles, often engaged in relatively third-class work, and certainly not the type of people you would want your sons or daughters to marry. But, nowadays, a foreigner down the street may have better SAT scores than you did, or higher degree from a better university. He might also be your son's or daughter's next employer.

    The traditional role models are getting mixed up, and it looks like this is just the beginning of a new chapter. Today, the whole thing has totally changed. It's not about where people are from or what color their skins are. It's about who they are, what values and skills they bring, and how they think.

    More than two thirds of the world's polar bears will be wiped out by 2050, according to a shocking new study. By then, scientists say, global warming will have melted 42 percent of the Arctic sea ice. By 2100, only a very few of these important creatures will be left.

    The report has been produced by the US Geological Survey. The scientists have publicized their findings in the hope of influencing US Interior Secretary Dirk Kempthorne, who has been asked to put polar bears on the US endangered species list.

    Polar bears depend on floating sea ice as a platform for hunting seals, which are their main food. Without enough ice, polar bears would be forced to go onto the land, where they are poorly skilled hunters, and would be unlikely to adapt to the life on the land in time. Experts say few little bears would survive and the stress could make many females unable to get pregnant.

    The team of American and Canadian scientists spent six months studying bears, on the ground, from spotter planes and in the lab, using computer models. Some team members fear the result is even worse for the bears than what their report says. They say the Arctic is warming faster than anywhere in the world and much faster than their computer had been forecasting. Satellite observations have showed that the ice has decreased to an all­time low.

    However, not everyone in the scientific community believes that global warming is happening on such an alarming scale. Another investigation has found that polar bears are still being hunted by wealthy “sportsmen” who want their skins and heads. At least ten international companies offer bear­hunting trips.

    Do you like to show off your expensive items? You could find yourself without friends! Scientists prove that expensive status symbols make you look less socially attractive.

    Items such as a fancy car and a Rolex watch are often thought to increase our social standing(地位) and often come with a high price tag(标签).According to the latest research, however, it has the opposite effect and people would prefer to be friends with someone who places less value on material objects.

    "Often we think that status symbols will make us look more socially attractive to others," says Stephen Garcia, the study's leading author from the University of Michigan. He adds, "However, our research suggests that these status signals actually make us look less socially attractive.

    The researchers conducted six studies which assessed how people presented themselves and how people viewed strangers. People who chose to wear higher status items tended to get a negative response, but people wanted to be friends with people who preferred lower status symbols.

    The study took the role of the luxury(奢侈) item to see if it was possible that the expensive item itself played a part in people's reactions. The definition of a status symbol changed based on a person's socioeconomic status, but the same effect of keeping off potential friends was seen regardless of social position.

    "At a social level, we may be wasting billions of dollars on expensive status symbols that finally keep others from wanting to associate with us, "says Kimberlee Weaver Livnat at the University of Haifa. She says, "And to the extent that close friendships are important to well-being, and we may be unintentionally hurting ourselves."

    However, Patricia Chen of the National University of Singapore said this does not necessarily mean status symbols are a bad thing. She says, "Our findings right now only apply to the formation of new friendships. Status symbols may be beneficial at other times and in other settings, such as when trying to establish new business contacts."