Tulou, the special residential architecture of Fujian Province was included on the UNESCO's World Heritage List during the 32nd session of the World Heritage Committee in Quebec, Canada.

    In the fourth century, Han Chinese living in the Central Plains area began to migrate south, gradually gathering in Fujian and forming the Hakka communities. As a defence against enemies, the Hakkas chose to live in compact (紧凑的) communities, and the tulou was their preferred houses. Tens of thousands of such earthen structures were constructed in Fujian Province.

    Most tulous are to be found in the valleys, surrounded by high mountains, and some are in the depths of the great mountains. Most are three to four storeys high, and look like circular blockhouses (堡垒). Rooms on the first floor are used as kitchens, rooms on the second floor are used as barns (谷仓), and rooms on the third and fourth floors are for bedrooms and living rooms. For defensive purposes, the rooms on the first floor have no windows.

    Raw materials for the tulou were obtained locally. Their main building material was a mixture of clay, sand, lime and water, and egg whites, brown sugar and rice water were added as adhesive agents (粘合剂). It was then mixed to form the walls. Once they dried, the walls were so hard that driving a nail into them would have been difficult. Fir branches, which are extremely strong and do not rot, were used to strengthen them, and many centuries later they have remained their original look.

    Tulous are located in a region where earthquakes happen frequently, and their circular construction helps them resist the regular shocks.

    The proven design even inspired one famous Peruvian architect, who paid several visits to Yongding, to build a tulou back home. Not long after, an earthquake struck only 10 kilometers away, and while all the houses around the earthen building fell down, his tulou remained.

    Most nations have at least one type of food that people from other countries think is unusual or unacceptable to eat. In France, people eat horse meat and frog legs. In South Korea and parts of China, restaurants serve dog meat. And in Australia, it's common to cook kangaroo meat on the barbecue and use emu eggs to make pancakes.

    The kangaroo and emu are native to Australia. Both animals are important to the national image of Australia and appear on the Australian coat of arms. They're also central figures in the history of the native Australians. However, they still hunt these animals for their meat, fur and fat.

    Today, Australian people continue to eat these animals. One of the reasons people eat kangaroo meat is that it's high in protein and low in fat, so eating kangaroo is a good option for anyone on a diet. It's also cheaper to eat kangaroo meat than other red meats. Because of this, a lot of university students choose to buy kangaroo meat. BBC News also reported that Australian scientists believe that eating kangaroo meat is good for the environment— kangaroos have different digestive systems than cows and sheep, meaning they produce less methane, the second biggest contributor to global warming.

    While emu meat is high in iron and vitamin C, most people don't think it tastes good. For this reason, they prefer emu eggs. One egg is large enough to make seven omelettes (煎蛋). And while ifs illegal to collect emu eggs from the wild, they can be bought from emu farms. Rather than cracking the beautiful dark shell, it's better to dry it by putting a small hole at each end and blowing. Afterwards, you can even carve a design into the eggshell.

Industrial emissions (排放) of carbon dioxide and other planet-warming greenhouse gases have raised the global average temperature by about 0.8℃ since the beginning of the Industrial Revolution. But studies have disagreed about what impact the rise is having on the world's species, says Mark Urban, an ecologist at the University of Connecticut, Storrs. Some have estimated that as many as 54% of species could eventually become extinct as a result of the climate change, but others have suggested no significant impact.①

    Such disparate result might originate from the limited nature of some individual studies, possibly because they focused only on a few species or a relatively small geographical region, says Urban.② To address these limits, Urban used statistical methods to help blend the results of previous studies into an apples-to-apples comparison that estimates the risk of extinction of species worldwide.

    ③He chose to analyze only the results of studies that had assessed extinction risks of more than one species. Then he researched into the details, such as the regions in which species considered, whether those species were limited to one small region or were widely spread, and whether the species were free to move as climate changed or were blocked by barriers such as mountain ranges or urban development.④

    Effects of climate change aren't always immediate, Urban says, and the risks of extinction he's estimated are the long-term results of species not being able to find a suitable habitat. Maybe the habitat will merely shrink to a size that can't support the species, or maybe it will disappear entirely. In some cases, he notes, a species might not be able to outpace the shift in its range, dying out before it can reach a new homeland. For over the generations that rapid warming might kill them off before they can spread to a suitable new habitat.

    Artificial intelligence (AI) technology may soon be a useful tool for doctors. It may help them better understand and treat diseases like breast cancer in ways that were never before possible.

    Rishi Rawat teaches AI at the University of Southern California's (USC) Clinical Science Center in Los Angeles. He is part of a team of scientists who are researching how AI and machine learning can more easily recognize cancerous growths in the breast. Rawat provides information about cancer cells to a computer. He says this data helps the machine learn. “…You can put the data into them and they will learn the patterns and the pattern recognition that's important to making decisions.”

    David Agus is another USC researcher. He believes that “machines are not going to take the place of doctors.” He adds, “Computers will not treat patients, but they will help make certain decisions and look for things that the human brain can't recognize these patterns by itself.”

    Once a confirmed cancerous growth is removed, doctors still have to treat the patient to reduce the risk of cancer returning. The form of treatment depends on the kind of cancer. Currently, researchers take a thin piece of tissue, put it on a small piece of glass and add color to better see the cells. This process could take days or even longer. Scientists say artificial intelligence can do something better than just count cells. Through machine learning, it can recognize complex patterns, or structures, and learn how the cells are organized. The hope is that machines will soon be able to make a quick diagnosis（诊断）of cancer that is free of human mistakes.

    “All of a sudden, we have the computing power to really do it in real time...We couldn't have done this, we didn't have the computing power to do this several years ago, but now it's all changed.” Agus adds that the process could be done “for almost no cost in the developing world.” He says that having a large amount of information about patients is important for a machine to effectively do its job in medicine.

    A doctor faces a series of critical decisions every day. The best a doctor can do is to make those decisions as informed as possible. Some of them are still hard to make. A doctor can ask people of whom he values their opinions and that's it. Imagine discussing these with an AI system that is even more rational（理性的）than anyone else.

    The University of Southern California researchers are now only studying breast cancer. But doctors predict artificial intelligence will one day make a difference in all forms of cancer.

    I have learned something about myself since I moved from Long Island to Florida three years ago. Even though I own a home in Port St. Lucie just minutes from the ocean, an uncontrollable urge wells up to return to Long Island even as others make their way south. I guess I am a snowbird stuck in reverse. Instead of enjoying Florida's mild winters, I willingly endure the severe weather on Long Island, the place I called home for 65 years.

    I'm like a migratory bird that has lost its sense of timing and direction, my wings flapping against season.

    So what makes me fly against the tide of snowbirds? The answer has a lot to do with my reluctance to give up the things that define who I am. Once I hear that the temperature on Long Island has dipped into the range of 40 to 50 degrees, I begin to long for the sight and crackling sound of a wood fire. I also long for the bright display o£ colors — first in the fall trees, and then in the limits around homes and at Rockefeller Center. Floridians decorate too, but can't create the special feel of a New England winter.

    I suppose the biggest reason why I return is to celebrate the holidays with people I haven't seen in months. What could be better than sitting with family and friends for a Thanksgiving turkey dinner, or watching neighbors' children excitedly open gifts on Christmas? Even the first snowfall seems special. I especially enjoy seeing a bright red bird settling on a snow-covered branch (My wife and I spend winters at a retirement community in Ridge, and I'm grateful that I don't have to shovel.）

    While these simple pleasures are not unique to Long Island, they are some of the reasons why I come back. Who says you can't go home?

    You can tell a lot about a country by what's on its television sets. Britain's TV screens are completely steeped in class, and have long been so.

    From laughing at poor people in reality shows to laughing at posh people in Downton Abbey, this is how Britain likes to unwind in the evening: by laughing at other classes, and laughing at people for laughing about class.

    Like it or loathe it, many see the class system as a quite essential element of British life, together with our obsession for tea and cake and talking about the weather.

    Whether you are a lord, a lady, or just the king of your own middle class kingdom, everyone in the UK fits into the class system. How the class system works is a hard question even for a British person to answer.

    There are four main groups in the British class system: lower, working, middle and upper class. Although recently the BBC has tried to confuse everyone even more by adding three more categories.

    The British are very aware of class; it is often said that we have an in-built 'class radar'; we pick up on subtle social clues which indicate which class a person comes from. Class is not just about your job, where you live and how much you earn. It's about who you are.