Now, a new study suggests that coffeefans can make their drink taste sweeter by simply changing the color of theircups.

Scientists claim that blue and glass mugs,which are popular in some coffee shops, can reduce coffee's bitterness, withoutany need for sugar, and that coffee drunk from white cups tastes the bitterest.

    To prove their claims, the researchersinvited 36 volunteers and used three different colored cups— blue, white andtransparent glass—to do an experiment.

    In the experiment, coffee consumed fromthe white cup was found to taste less sweet when compared to the other twocolored cups, while the blue cup made the coffee taste the sweetest.

    The scientists believe that the colorbrown may be associated with coffee's bitterness because coffee in a white cupappears the brownest and tastes the bitterest.

  “Our study clearly shows that the colorof a coffee cup does influence the perceived (感受到的) taste and flavor of coffee,” said DrGeorge Doorn of Federation University Australia, “but the potential effects maybe different between a one-time purchase and a return customer.”

  “Anyhow, the effect of the color of thecup on the flavor of the coffee suggests that café owners, baristas (服务员), aswell as coffee cup manufacturers should carefully consider the color of theircups, ” he added.

    However, the idea that color can alterthe taste of food and drink is not new.

    A study published last year revealedthat red, strawberry-flavored mousse (慕斯蛋糕) served on a white plate was rated as10 percent sweeter and 15 percent more flavorous than the same food presentedon a black plate.

    Hummingbirds(蜂鸟) are one of nature's most energetic fliers and the only birds to hover(盘旋) in the air by relying on their strength alone.

    Now scientists have found that it is the ratio(比值) of the bird's wing length to its width that makes them so efficient. The discovery is helping experts compete with 42 million years of natural selection to build helicopters that are increasingly efficient.

    David Lentink, an assistant professor at Stanford University in California, tested wings from 12 different species of hummingbirds, which he sourced from museums. He placed them on a machine used to test the aerodynamics(气力学) of the helicopter blades(桨叶). Professor Lentink's team used the same machine to test the blades from an advanced micro-helicopter used by the UK's army. They found that the micro-helicopter's blades are as efficient at hovering as the average hummingbirds.

    But while the micro-helicopter's blades kept pace with the average hummingbird wings, they could not keep up with the most efficient hummingbird's wing. The wings of Anna's hummingbird were found to be about 27 percent more efficient than the man-made micro- helicopter's blades.

    While Professor Lentink wasn't surprised at nature's superiority, he said that helicopter blades have come a long way. “The technology is at the level of an average hummingbird,” he said. “A helicopter is really the most efficient hovering device that we can build. The best hummingbirds are still better, but I think it's amazing that we're getting closer. It's not easy to match their performance, but if we build better wings with better shapes, we might match hummingbirds.”

    Professor Lentink said that we don't know how hummingbirds maintain their flight in a strong wind, how they navigate(确定方向) through branches, or how they change direction so quickly. He thinks that great steps could be made by studying wing aspect ratios-the ratio of wing length to wing width. Understanding these abilities and characteristics could be a benefit for robotics and will be the focus of future experiments.

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    Almost every night for more than 10 years, Kirk Alexander, 48, ordered a late dinner from his local restaurant Domino's Pizza. But for the past two weeks, he hasn't called for even once.

    “A few of my staff mentioned that we hadn't seen his order in a while. Then I found that it had been 12 days since he last ordered, which is not like him,” Domino's general manager Sarah Fuller said, feeling she could no longer ignore Kirk's recent absence.

    Sarah has known Kirk since 2009, when she started working at the Domino's Pizza as a deliver driver and often made the short trip to Kirk's home about six minutes away. She knew Kirk worked from home, and neighbors said he seldom left. She also knew that he had some health problems in the past. Something, Sarah worried, was wrong.

    Around 1 a.m. on May 8, Sarah sent delivery driver Sean Hamblen to visit Kirk's home. Sean arrived at Kirk's home and knocked on the front door several times. There was no answer. He later noticed that the lights and the TV in the home were on. When he called Kirk's phone, it went straight to voice mail.

    Sean drove back to the restaurant to tell Sarah and they decided to call 911. Soon, officers arrived at Kirk's home. So did Sarah and Sean. They heard a man calling for help from inside. Officers broke down the door and found Kirk on the floor in need of medical attention at once after suffering from a heart attack. One day later, they might have been too late.

    So is keeping an eye on regular customers part of Domino's business plan? Not really. “Kirk is part of our family here and we feel like we need to do something.” Sarah said.

    Here are four wonderful hotels and campsites in Europe.

    Ekies All Senses Resort, Chalkidiki, Greece

    This could be the perfect retreat for stressed parents who need spoiling. For a start, it's in lovely Greece, but there's no need to take a ferry, as it's on the mainland. With a juice bar beside the(heated)pool, open-air spa, calm beach, restaurants or meals on demand, and secret bays to explore by boat, it makes for a super-relaxed break.

    Doubles from € 88, junior suite(sleeps 4)from €138 a night, family suite(sleeps6) from €272 B&B, open late

    April-October, i-escape.com

    Casa Vicentina, Algarve, Portugal

    For a back-to-nature feel, family-run Casa Vicentina in the Algarve is perfect. Built with ecological materials, it's in a protected park area on a natural lake. Breakfast is a plentiful buffet-and bikes are supplied free of charge so you can go to the beach or cafes and restaurants. Accommodation is in brightly decorated rooms or larger suites complete with small kitchens.

    Rooms from €75 B&B, wonderfulland. Com

    Fairy Chimney Inn, Cappadocia, Turkey

    Older kids will love the fairytale landscape of Cappadocia and the excitement of staying in a cave hotel. The Fairy Chimney Inn used to be part of a cave monastery(修道院). Its rooms are beautiful and homely, with traditional decorations and the occasional reminder of the modern world. All rooms have courtyards overlooking the  extraordinary landscape.

    Rooms from €55 B&B, plus 11 per child, fairychimney. Com

    Casa San Gabriel, Umbria, Italy

    Casa San Gabriel is a small hilltop farm where three self-catering cottages share a swimming pool, playground and barbecue. There's added excitement for young guests in the family of alpacas(羊驼)kept on site. There are several water, wildlife and activity parks nearby, and slightly further afield a Pinocchio theme park.

    A week at II Fienile cottage (sleeps 4-6)costs from €650, B&B (low season only) from €95, casasangabriel. com

    People in South Korea who feel they can no longer bear the stress of everyday life now can choose to stay in a prison to relax and think deeply.

    In a society where pressure to do well in school and find highly-paid jobs is intense, a former lawyer came up with an extreme relaxation idea. Kwon Yong-seok created the "Prison Inside Me" —a stress-reduction center with a punishment theme. People come here to cut themselves off from the outside world and pay to be kept in 60-square-foot (5.6-square-meter) cells (囚室).

    Located on the outskirts of Hongcheon, about 58 miles (93 km) northeast of Seoul," Prison Inside Me" came to life after Mr. Kwon voluntarily asked to spend time behind bars for" healing reasons," but his request was turned down." I didn't know how to stop working back then," he said." I felt like I was being swept away against my will, and it seemed I couldn't control my own life." So, Kwon and his wife Roh Ji-hyang decided to take matters into their own hands, and designed and built a prison-like spiritual center. The construction was completed in June last year and cost about 2 billion won ($19 million).

    The facility includes 28 cells, furnished with only a toilet, a sink and a small table, where guests can spend time alone, thinking about life and enjoying private thinking periods. Moreover, guests can also join group thinking periods in the hall, where they are given instructions on how to free themselves from what Mr. Kwon calls the "inner prison" to find inner peace.

    According to the Wall Street Journal, hundreds of stressed South Koreans are checking in at the stress-reduction facility to think about their lives and regain control of it. A two-night stay at" Prison Inside Me" costs 150,000 won ($146).

    Mr. Kwon and his wife explained that at the beginning they had a different plan for the" relaxation center," and imagined a longer stay for their guests, but, given that people weren't able to take more time off, they had to reduce the length of stays to just two days.

    Park Woo-sub, a guest at" Prison Inside Me," said the experience helped him a lot." This is my third time in prison. Being kept in a prison makes me hard to breathe, but it also offers time to focus only on me and spend some quiet time with myself."

    Others said the experience would have been more helpful if the conditions had been poorer, like in a real prison.

    As early as 2005, there were a number of new stories about dog cloning(克隆) and cat cloning. Animal cloning had been old news for nearly a decade by then, with the revolutionary (革命的) cloning of Dolly the sheep in Scotland.

    However, Snuppy was the first pet, a dog, to be cloned. Since the cloning of Snuppy, there has been some very successful cloning of pets and other animals. Lou Hawthorne started BioArts while cloning his beloved mixed-breed dog Missy. Hawthorne was very pleased with the results of the cloning, producing three successful clones that were very alike to the original in character and behavior. In January, 2009, a Florida couple, Ed and Nina Otto, announced that they had paid to have their dog cloned by BioArts.

    All new technology is overpriced. For example, personal computers were not very affordable at first. Only after the producing process was improved was it possible for every family to have a computer. How much room there will be for organizations to reduce the price point on pet cloning without broad demand is of course questionable.

    There are many great dogs and cats that can be found at the local dog pound (野狗收容所) or are given away for "free to good homes" in classified ads (分类广告). However, there is no limit to the value people place on a beloved pet. The Ottos are a good example of that. If people can buy a dog or cat with predictable behavior and characteristics, there is value in that. There is a predictable market here, though it may always be limited in size.

    While pet cloning has not taken off as some hoped, it's clear that it will become a bigger market in the future and it will be increasingly possible for people to try this out. With the inevitable (不可避免的) success that cloned pet owners will have, the practice will become more widely accepted and it seems inevitable that there is a future for cloned dogs and cats.