Look into hunters' eyes

    Have you ever been face to face with a cat or a sheep? If you have,you probably noticed that cats narrow their eyes to vertical (垂直的) slits (狭缝),while sheep have horizontal pupils (瞳孔).

     Why is the difference?

    Scientists from the Universities of California Berkeley and Durham in Britain may have the answer. Their research, published recently in the journal Science Advances, suggested that pupils' shapes could tell whether an animal is a hunter or gets hunted.

    The researchers took a close look at the eyes of 214 land animals.The challenge was to see if they could find a relationship between an animal's role in the food chain and the pupils' shapes.

    They found a pattern. Species with pupils that are vertical slits are more likely to be small ambush predators (捕猎者) – creatures that lie in wait for their lunch.In contrast,those with horizontal pupils are more likely to be plant-eating prey (猎物) species.

    Evolution chose the arrangement for a good reason.For hunters such as household cats,it appears that vertical pupils not only improve their ability to keep track of moving objects like mice,but also maximize (使最大化) their ability to judge the distances of the animals they hunt.

    However, an interesting discovery from the study is that the slit pupils are mostly linked to hunters that are close to the ground. Therefore, bigger cats who actively hunt down their prey, like tigers and lions, don't have slit pupils.

    On the other hand, for plant-eating prey animals, horizontal pupils give them a wider field of vision.When stretched (伸展) horizontally,the pupils allow for more light to enter from the front, back, and sides. Meanwhile, they also limit the amount of light from the sun above so the animal can see the ground better.“ Once they do find a predator,they need to see where they are running,” said leading researcher Martin Banks,a UC Berkeley professor of optometry (视光学).“They have to see well enough out of the corner of their eye to run quickly and jump over things.”

    But what happens when they bend down to eat? Researchers checked this by watching prey animals in the Oakland Zoo in California, US. They believe that when goats lower their heads to eat,their eyes rotate (旋转) to keep their pupils horizontal.

    So it seems that the eyes are indeed the window to the soul!

    A new family moved in next door and I got to meet the mother of the family, Lydia. Lydia is Korean, and her family moved to our city so her husband could go to graduate school. We started talking, and she was apologetic about how bad her English was, but I didn't care. I knew how hard it was to learn a second language. I enjoyed chatting with Lydia as we watched our kids play.

    It was what came next that challenged me: Lydia asked if I'd be willing to help her with her English. Now, I am not a teacher. I admire teachers, and I'm grateful for teachers, and it's because I admire what they do so much that I was very very sure that I couldn't do it myself.

    But Lydia was sure that she wanted my help. I was doubtful. I wasn't sure my "help" was even worth being called by that name. But because she asked me, I said "yes." And that was the beginning of a friendship. Lydia and I spent afternoons sitting together and reading the newspaper, and as we did, she asked me questions when she had them questions about language, yes, but also questions about the new culture she found herself in. In turn, I asked my own questions, growing curious about her home country and culture. We bonded over our shared faith and our struggles as mothers of kids with special needs, When I complimented（恭维） her cooking, she began to teach me about Korean food, eventually leading to a shared trip to explore the Korean grocery stores in our city. Because of Lydia, 1 learned more about my own hometown than I ever could have learned by myself. I'm still not sure that I'm any good as a teacher. But I'm grateful I said "yes" when my neighbor asked me to help her with her English. That meant spending extra time with my neighbor, and that extra time meant she didn't remain just my neighbor. She became my friend.

    From roller coasters to adventure tours performances to experiments, there are plenty of exciting attractions in the UK. Here is our pick of the best attractions that children can visit.

    The Natural History Museum

Why go: This really is the grandfather of all London museums—the beauty of the building and the amazing exhibits. Look out for the whale skeleton(骨架) occupying the entry hall, but don't miss the largest piece of gold (or a model of it) in the minerals gallery. You can easily spend a day here—tasty steaks, sandwiches and pizzas. Try to avoid weekends, because the crowds are larger

    Best for: Children aged 5 and over. If time is limited, families should go quickly and directly towards the dinosaur gallery, because it's really wonderful.

    Details: Entry is free, although there is a charge for some temporary exhibitions

    Legoland

    Why go: Some 80 million Lego bricks have gone into the creation of this colourful park. There are thrilling rides and countless ways to spend money in shops. Yes, the queues can be long (unless you pay extra for the queue-jumping equipment, which is useful though it does not cover all rides)

    Best for: Legoland is aimed at children under10s, with pre-schoolers particularly well catered for in Duplo Valley

    Details: ￡32 per person; under 3s go free. 25 per cent discount for booking online more than seven days in advance.

Warner Bros. Studio Tour London —The Making of Harry Potter

    Why go: You've read the books, you've watched the films, but no Harry Potter fan will want to miss the chance to go behind the scenes at the film studios where all eight of the movies were made. Sharing the secrets behind the most successful film series of all time and yet still managing to keep the sense of magic alive, this studio tour gives visitors access to two locations filled with original sets and costumes

    Best for: Children aged 7 and over, and anyone with an interest in filmmaking

    Details: ￡39 adults; ￡31 children; under 4s go free

    Professional athletes pay a high price for their pursuit of excellence and glory. Training to the limit tears muscles and wears out joints. Gymnasts often need hip replacements when barely into middle age. Few footballers make it to the end of their careers with their knees intact.

    But many also run a darker risk: doping—the use of banned athletic performance-enhancing drugs by athletic competitors. The Winter Olympics in Pyeongchang, in South Korea, starts this week in its shadow. Years after whistle-blowers first revealed wholesale (大规模的) doping in Russia, the International Olympic Committee (IOC) at last decided to bar it from taking part. But it has allowed many Russians to compete as individuals. And on the eve of the competition the Court of Arbitration for Sport (CAS) said that 28 others should receive a more tolerant penalty from the IOC, further muffling the anti-doping message.

    Russia's doping is unusual only in its scale and institutional nature. No country or sport is immune. Studies, and an anonymous survey at the World Athletics Championships in 2011, suggest that a third of athletes preparing for big international competitions take banned substances. Yet just 1-2% fail a test each year. Lance Armstrong, a cyclist who won the Tour de France seven times and later admitted to doping all the while, was tested on 250 occasions. The few times he failed, he avoided punishments by claiming he had taken anti-inflammatories (消炎药) for saddle-sores (骑行引起的肌肉酸痛).

    Doping is more sophisticated than when some states used steroids (类固醇) to bulk up athletes. New drugs are designed to be undetectable in a blood or urine sample. Many athletes "blood dope," receiving transfusions or taking a drug that stimulates the production of red blood cells to improve their physical strength. Soviet athletes who were fed steroids suffered a host of serious problems in later life. They were more likely to commit suicide, or to miscarry (流产) or have a disabled child. No one knows what risks those taking new "designer" versions are running. Blood-doping can cause heart attacks; more than a dozen cyclists' deaths have already been linked to it.

    The agencies that set out to stop doping are hugely outclassed. As the argument over punishments on Russia illustrate, they are divided and weak. Most testing is done by national bodies, which may not try very hard to find evidence that would get their own stars banned. The World Anti-Doping Agency (WADA), which oversees them, is packed with officials from national sports federations and the IOC. Their interests are likewise conflicted. Its budget is tiny. The system seems to be designed to look tough but punish only the occasional scapegoat (替罪羊). Honest athletes deserve better.

    Andrew Ritchie, inventor of the Brompton folding bicycle, once said that perfect portable bike would be "like a magic carpet... You could fold it up and put it into your pocket or handbag". Then he paused: "But you'll always be limited by the size of the wheels. And so far no one has invented a folding wheel."

It was a rare — indeed unique — occasion when I was able to put Ritchie right. A 19th-century inventor, William Henry James Grout, did in fact design a folding wheel. His bike, predictably named the Grout Portable, had a frame that was divided into two and a larger wheel that could be separated into four pieces. All the bits fitted into Grout's Wonderful Bag, a leather case.

    Grout's aim: to solve the problems of carrying a bike on a train. Now doesn't that sound familiar? Grout intended to find a way of making a bike small enough for train travel: his bike was a huge beast. And importantly, the design of early bicycles gave him an advantage: in Grout's day, tyres were solid, which made the business of dividing a wheel into four separate parts relatively simple. You couldn't do the same with a wheel fitted with a one-piece inflated(充气的) tyre.

    So, in a 21st-century environment, is the idea of the folding wheel dead? It is not. A British design engineer, Duncan Fitzsimons , has developed a wheel that can be folded into something like a slender ellipse(椭圆). From beginning to end, the tyre remains inflated.

    Will the young Fitzsimons's folding wheel make it into production? I have no idea. But his inventiveness shows two things. First, people have been saying for more than a century that bike design has reached its limit, except for gradual advances. It's as silly a concept now as it was 100 years ago: there's plenty still to go for. Second, it is in the field of folding bikes that we are seeing the most interesting inventions. You can buy a folding bike for less than £1,000 that can be knocked down so small that can be carried on a plane ——minus wheels, of course ——as hand baggage.

    Folding wheels would make all manner of things possible. Have we yet got the magic carpet of Andrew Ritchie's imagination? No. But it's progress.

Not long after Tony Berlin began working at the state driver's license facility in Niles in 1985, he noticed that some truck drivers who should have failed their exams mysteriously passed them. For six years, starting in 1992, he collected evidence to show why: He believed truck drivers were bribing state workers to get licenses. In another turn of the screw, the workers were using those bribes to buy tickets to the then secretary of state George Ryan's fundraisers, including for his successful bid for governor. Berlin tried to expose the corruption (腐败)-he went to the FBI and the upper ranks of the secretary of state's office - but was repeatedly met with indifference. Then he began to suspect that the truck driver in a 1994 accident that killed six children, all from the same family, got his license through the scheme. In a moment that changed everything, Berlin reached out to the Reverend Scott Willis, the children's father.

It was his call to Willis that connected the crash to what would become known as the licenses — for — bribes scandal (丑闻), "Berlin's the one who started it says the Willises' lawyer. A few months after that phone call, the U.S. attorney's office initiated Operation Safe Road, an ongoing federal investigation that by the end of November had disclosed 34 offenses.

The investigation ultimately netted 75 offenses, including that of Dean Bauer, Ryan's inspector general. He pleaded guilty in 2001 to obstructing (妨碍)justice and was sentenced to 12 months in. prison. Bui the biggest catch was Ryan himself, who was sentenced in 2006 to six and a half years tor fraud and blackmailing. As for Berlin, he continued to work a stale license facilities, in Streator and Pontiac, choosing to stay out of the public eye.