A 9-year-old boy in Indian stopped a would-be carjacker（劫车贼）on Christmas Day from running away with his father's truck.

    Kevin Cooksey was inside the One Stop Express gas station in Kokomo buying medicine for his wife when a man jumped into the driver's seat of his truck. Cooksey had left the engine running and the door unlocked.

    "When I saw my truck door open, I was astonished, 'Oh my God, what am I going to tell my wife?'" Cooksey said.

    His son, Larry, was sitting in the back seat. "As soon as he opened the door, I got frightened," said Larry. "So I pulled out the gun and pointed it to his head."

    This was enough to make the carjacker think twice and he jumped out of the truck to try another car. Parked beside Cooksey's truck was Kyle Sparling's black Trailblazer. He too had left the engine running as he went into the store. The man got in Sparling's SUV and took off.

    "I didn't know what to think, I just kind of ran outside and watched him," said Sparling.

    As the man sped off, Cooksey told Sparling to get into his truck and the two men began to run after him. The icy winter conditions made the driving difficult, but the pair followed at a safe distance as the carjacker drove in a "Z" way. After a few miles, the carjacker knocked into the sign of a local business, American Tool and Party Rental. Cooksey and Sparling called the police to the place.

    The police put 32-year-old Ollie Dunn into prison. Sparling's car was damaged in the wheel, and the windscreen got cracked after the sign fell on it. "I was just glad he didn't knock into anybody," Sparling said. "That was my biggest fear, I think."

    Icelanders have a beautiful tradition of giving books to each other on Christmas Eve and then spending the night reading. This custom is so deeply rooted in the culture that it is the reason for Christmas Book Flood, when the majority of books in Iceland are sold between September and December in preparation for Christmas giving.

    “Books get attention here.” says Baldur Bjarnason, a researcher who has written about the Icelandic book industry.

    The small Nordic island, with a population of only 329,000 people, is extraordinarily literary（文学的）. They love to read and write. According to a BBC article, “The country has more writers, more books published and more books read, per head, than anywhere else in the world... One in 10 Icelanders will publish a book.”

    It seems there is more value placed on physical, paper books than in North America, where e-books have grown in popularity. One bookstore manager said, “The book in Iceland is such an enormous gift —you give a physical book. You don't give e-books here” The book industry is driven by the majority of people buying several books each year, rather than the North American pattern of a few people buying lots of books.

    It sounds like a wonderful tradition, perfect for a winter evening. It is something that I would love to incorporate（吸收）into my own family's celebration of Christmas.

    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.

    I remember the day when I first learned to ride a bike. It was a frightening, yet fun experience. My granddad was the one who taught me, and he helped me when I got hurt. The first time I got on a bike, I had no idea what I was doing, and just about everything went wrong. My granddad told me to just put my feet on the pedals and start, pedaling(骑自行车). He also told me he would hold onto the back of the bike the whole time, yet he didn't.

    As soon as I started trying to balance myself, he let go. I happened to look back just then.  I was scared to death that I was going to fall and hurt myself. When I was scared, my mind went blank from pedaling, and I just wanted off. I forgot how to use the brakes(车闸) and fell right off the bike. My granddad kept encouraging me to get up and try again, and after about 15 minutes, I finally stopped crying, got up and tried again.

    As soon as I started pedaling again, my pants got caught in the chain, and I fell flat on my face and hit my nose. Since that happened, my granddad decided to call it a day and try again the next morning. The next morning I woke up bright and early, and was very eager to try to ride my bike. My nose felt better, so I wasn't that afraid of falling anymore.

    Though I knew there were a lot of difficulties on the way to mastering the skills in riding a bike, l believed I could do well with my granddad's help. After all, riding a bike was what I wanted to do eagerly.

    Still seeking a destination for your weekend break? There are some places which are probably a mere walk away from your college.

    King's Art Centre

    A day at the Centre could mean a visit to an exhibition of the work of one of the most interesting contemporary artists on show anywhere. This weekend sees the opening of an exhibition of four local artists.

    You could attend a class teaching you how to learn from the masters' or get more creative with paint—free of charge.

    The Centre also runs two life drawing classes for which there is a small fee.

    The Botanic Garden

    The Garden has over 8,000 plant species；it holds the research and teaching collection of living plants for Cambridge University.

    The multibranched Torch Aloe here is impressive. The African plant produces red flowers above bluegreen leaves, and is not one to miss.

    Get to the display house to see Dionaea muscipula a plant more commonly known as the Venus Flytrap that feeds on insects and other small animals.

    The Garden is also a place for wildlife enthusiasts. Look for grass snakes in the lake. A snake called ‘Hissing Sid' is regularly seen lying in the heat of the warm sun.

    Byron's Pool

    Many stories surround Lord Byron's time as a student of Cambridge University.  Arriving in 1805, he wrote a letter complaining that it was a place of "mess and drunkenness". However, it seems as though Byron did manage to pass the time pleasantly enough. I'm not just talking about the pet bear he kept in his rooms. He spent a great deal of time walking in the village.

    It is also said that on occasion Byron swam naked by moonlight in the lake, which is now known as Byron's Pool. A couple of miles past Grantchester in the south Cambridgeshire countryside, the pool is surrounded by beautiful circular paths around the fields. The cries of invisible birds make the trip a lovely experience and on the way home you can drop into the village for afternoon tea. If you don't trust me, then perhaps you'll take it from Virginia Woolf—over a century after Byron, she reportedly took a trip to swim in the same pool.

    Sweet potato plants don't have spines or poisons to defend themselves. But some have evolved a clever way to let hungry herbivores (食草动物) know they aren't an all-you-can-eat buffet, a new study finds. When one leaf injured, it produces a chemical that warms the rest of the plant and its neighbors to make themselves inedible (不宜食用的)to bugs. Sweet potato breeders could potentially engineer plants to produce the chemical as an all-natural pest defense.

    Plant ecologists led by Axel Mithofer of the Max Planck Institute for Chemical Ecology in Jena, Germany, started to look into sweet potato (Ipomoea batatas) defenses after they noticed something interesting about two varieties of the plant grown in Taiwan: The yellow-skinned, yellow-fleshed Tainong 57 is generally herbivore-resistant, but its darker orange cousin, Tainong 66, is plagued (造成麻烦) by insect pests.

    To find out why, the team offered up Tainong 57 and 66 plants to hungry African cotton leafworm caterpillars (毛虫).Both plants released at least 40 airborne compounds as the caterpillars snacked on their leaves. But Tainong 57 produced a lot more of a chemical called DMNT, which has a very distinct smell, the team details this month in Scientific Reports. ("The smell is not nice," Mithofer says. "You wouldn't want it as a perfume.")

    DMNT isn't a new compound; researchers have isolated (分离出) the smelly chemical from other plants such as corn and cabbage, and it is known to induce defense responses in some species.

    To determine whether this was happening in sweet potatoes, scientists set up two experiments. First, they put two plants next to each other and wounded one so it produced DMNT. Then, they exposed healthy Tainong 57 plants to DMNT they had synthesized (合成).In both cases, the DMNT caused the exposed plants to produce more of a protein called sporamin in their leaves. (Tainong 66 did not have the same reaction.) When the caterpillar's snack on sporamin, "they immediately stop eating because they don't feel well," Mithofer says.

    Sporamin is the main protein in sweet potato tubers (块茎),and is indigestible raw, which is why sweet potatoes must be cooked for humans to enjoy them. "If the caterpillars could cook it, they could eat it," Mithofer says. Theoretically, he says, sweet potato breeders could use genetic engineering to make different varieties of sweet potato produce as much DMNT as Tainong 57, and display the same defense responses.

    Still, the research isn't ready for prime time, cautions plant ecologist Martin Heil. DMNT might work in the lab, but in the field, airborne chemicals can be "blown away in seconds," says Heil, who studies plant-insect interactions at the National Polytechnic Institute in Irapuato, Mexico.

    Mithofer himself has no plans now to create genetically engineered sweet potato plants, because they would not be a viable (能活下去的) crop in Europe, where genetically modified crops are outlawed. So for now, Tainong 66 will have to put up with being a caterpillar salad bar.