Music

    Opera at Music Hall: 1243 Elm Street. The season runs June through August, with additional performances in March and September. The Opera honors Enjoy the Arts membership discounts. Phone: 241-2742. http://www. cityopera.com.

    Chamber Orchestra: The orchestra plays at Memorial Hall at 1406 Elm Street, which offers several concerts from March through June. Call 723-1182 for more information. http://www.chamberorch.com.

    Symphony Orchestra: At Music Hall and Riverbend. For ticket sales, call 381-3300. Regular season runs September through May at Music Hall and in summer at Riverbend. http://symphony.org/home.asp

    College Conservatory of Music (CCM): Performances are on the main campus (校园) of the university, usually at Patricia Cobbett Theater. CCM organizes a variety of events, including performances by the well-known LaSalle Quartet, CCM's Philharmonic Orchestra, and various groups of musicians presenting Baroque through modern music. Students with I.D. cards can attend the events for free. A free schedule of events for each term is available by calling the box office at 556-4183. http://www.ccm.uc.edu/events/calendar.

    Riverbend Music Theater: 6295 Kellogg Ave. Large outdoor theater with the closest seats under cover (price difference). Big name shows all summer long! Phone: 232-6220. http://www.riverbendmusic.com.

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    Christmastime in the city brings forests of trees already cut and waiting to be sold. But some people like to drive to tree farms. Others wait for their trees to come to them. They order one from the pages of a catalog or on the Internet. Some say the easiest thing of all is to buy a man­made tree with Christmas lights already on it. No falling needles to have to clean up.

    The National Christmas Tree Association says 33,000,000 real trees were sold last year, compared to 9,000,000 man­made ones. Man­made trees generally cost more, but they can be reused. Most natural trees are cut up and recycled, but some people buy trees that can be planted.

    Most Christmas trees are now grown on farms instead of in forests. Twenty-one thousand tree farmers in the United States grow Christmas trees on more than 180,000 hectares. Oregon was the leading producer last year.

    Twenty-two percent of people who bought real trees last year chose them at a farm. Two percent of those people cut the trees themselves. The next most popular places were big stores like Walmart and Home Depot. Groups like the Boy Scouts also sell Christmas trees. But some people pay nothing for theirs. They steal it.

    Cornell University in Ithaca, New York, has many pretty evergreens. Some years ago, a university worker found a way to keep them there. A month before Christmas, workers treated them with “pink ugly mix”. It contains water and red food colour. The bright colour starts to disappear after about a month. It can take longer, however. Cornell decided not to use the mix this year, but the idea has spread.

    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just a bunch of individual components (零件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. “The added difficulty with such a project is that actually none of those components are off the shelf and so we have to make them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of individual components, each of which individually has to perform well, and then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    Wood says the design offers a new way to study flight mechanics and control at insect- scale. Yet, the power, sensing and computation technologies on board could have much broader applications (应用). “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

Plastic-Eating Worms

    Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills(垃圾填埋场), and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms.

    Researchers in Spain and England recently found that the worms of the greater wax moth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms' chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物) and applied it to plastic films. 14 hours later the films had lost 13% of their mass — apparently broken down by enzymes (酶) from the worms' stomachs. Their findings were published in Current Biology in 2017.

    Federica Bertocchini, co-author of the study, says the worms' ability to break down their everyday food — beeswax — also allows them to break down plastic. “Wax is a complex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well,” she explains, “The wax worm evolved a method or system to break this bond. ”

    Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?

    Bertocchini agrees and hopes her team's findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply “millions of worms thrown on top of the plastic.”

    Valentine's Day is named after Saint Valentine, an early Christian churchman who helped young lovers. Valentine was killed for his Christian beliefs on February 14 more than 1,700 years ago, but the day that has his name is even earlier than that.

More than 2,000 years ago, the ancient Romans celebrated a holiday for lovers. As part of the celebration, girls wrote their names on pieces of paper and put them in a large container. Boys reached into the container and pulled one out. The girl whose name was written on the paper became his lover or sweetheart for a year. Today, lovers still put their names on pieces of paper and they send each other Valentine's Day cards that tell of their love. Sometimes they also send gifts, like flowers or chocolate candy. Americans usually send these gifts and cards through the mail system. But some used another way to send this message. They have it printed in a newspaper. The cost is usually a few dollars. Some of the messages are simple and short, “Jane, I love you very much.” Others say more. This one, for example, “Roses are red. Violets are blue. I hope you love me as much as I love you. Forever, Mary.”

    Most of the newspapers that print such messages are local, but USA Today is sold throughout the United States and 90 other countries as well. This means someone can send a Valentine message to a lover in a far-away city or town almost anywhere in the world. These messages cost 80 dollars and more. An employee of USA Today says readers can have a small heart or rose printed along with their messages this year. Will this kind of Valentine's Day message reach the one you love? Well, just make sure he or she reads the newspaper.

    HANGZHOU — Chinese internet giant Alibaba on Tuesday opened a hotel loaded with artificial intelligence (AI) and robots, automating a series of procedures like check­ in, lights control and room service.

    FlyZoo Hotel, opened in Hangzhou, capital of East China's Zhejiang province, where Alibaba is headquartered, is known as the company's "first future hotel". Customers can check into the hotel by simply scanning their faces. The facial recognition system installed in the hotel also enables customers to use their faces as key cards to open doors and access another hotel service. Users can also control the lights, televisions and curtains in the room via Alibaba's voice­activated digital assistant, while robots are deployed to serve dishes, cocktails and coffee. Hotel bookings and check­out can also be done with a few clicks on mobile through an app. "The AI­based solution can help customers save time and relieve hotel employees from repetitive work," said Wang Qun, CEO of FlyZoo Hotel. The hotel is the latest example of Chinese tech companies' attempt into traditional industries such as the hotel industry.

    E­commerce giant JD.com announced in October its strategy to put smart home and electronic devices sold on its platform into hotels, in an effort to improve online sales.

    In July, Baidu teamed up with Intercontinental Hotels Group in Beijing to allow guests to use its voice­ controlled assistant to adjust room temperature and order room service at ease.

    Before that, social media giant Tencent introduced QQfamily, a similar tech solution for hotel operators, in the southern city of Zhuhai last year.

    "We want to install a 'smart brain' for hotels," said Wang. "In the future, we will continue to make hotels smarter and more automated, as well as create more personalized experiences for consumers."