Is there a magic cutoff period when offspring become accountable for their own actions? Is there a wonderful moment when parents can become spectators (旁观者) in the lives of their children and shrug, "It' s their life," and feel nothing?

    When I was in my twenties, I stood in a hospital corridor waiting for doctors to put a few stitches in my son's head. I was asked, "When do you stop worrying?" A nurse said, "When they get out of the accident stage." My mother just smiled faintly and said nothing.

    When I was in my thirties, I sat on a little chair in a classroom and heard how one of my children talked incessantly, disrupted (打断) the class, and was headed for a career making license plates. As if to read my mind, a teacher said, "Don't worry. They all go through this stage, and then you can sit back, relax, and enjoy them." My mother listened and said nothing.

    When I was in my forties, I spent a lifetime waiting for the phone to ring and the cars to come home, the front door to open.

    My friends said that when my kids got married I could stop worrying and lead my own life. I wanted to believe that, but I was haunted by my mother' s wan ( 淡淡的 ) smile and her occasional words, "You look pale. Are you all right? Call me the minute you get home."

    Can it be that parents are sentenced to a lifetime of worry? Is concern for one another handed down like a torch to blaze the trail of human frailties and the fears of the unknown? Is concern a curse? Or is it a virtue that elevates us to the highest form of life?

    One of my children became quite irritable recently, saying to me, "Where were you? I've been calling for three days, and no one answered. I was worried!!!"

    I smiled a wan smile.

    Oh my God, the robots are taking over! We're doomed! Doomed! Now that I've gotten that out of my system, it's become clear that while we may or may not be doomed, the robots are taking over. The latest example is the government's new guidelines for self-driving cars.

    Tesla, Google and Uber are already testing driverless cars in cities across America. Uber chief executive Travis Kalanick is among those predicting that by 2021, self-driving cars will play a big part in urban settings.

    Nearly 40,000 people died last year in this nation in automobile-related accidents, and we believe driverless cars can save tens of thousands of lives annually.

    It makes sense. Robot drivers are less likely to get drunk, drive without a license, text while driving or feel agitated at the scene of a traffic jam. On the other hand, I wonder how these highly sensitive cars will react with walkers constantly dashing into the street. Will they jam on the brakes every 10 seconds?

    But there's a bigger picture. Not only are robots replacing humans behind the wheel, but behind the work desk, in warehouses, senior homes, you name it. Robots aren't just taking over in the workplace.

    The question is, where can't a robot function better than a human? How about writing songs? A robot can go through every combination of notes in record time and come up with a pleasing melody. The lyrics might be a different story. Is a Grammy-winning song co-written by Hank Human and R-3071 in our future?

    Finally, it's only a matter of time until we have robot politicians and presidential candidates. Why not? They can be programmed to be experts in world and domestic affairs and come up with the best solutions without corruption and bad humors.

    Actually, it's too bad such technology isn't available in 2018. Pretty sure the robot would win in a landslide.

    Swiss researchers said Monday they have developed a wireless camera system to monitor vital signs in premature babies, a move that could replace uncomfortable and highly inaccurate skin sensors (传感器) which produce false alarms in up to 90 percent of cases, mainly set off by the baby's movement.

    “This is a cause of discomfort for the babies, because we have to check on them every time,” said Jean-Claude Fauchere, a doctor at University Hospital Zurich's newborn clinic.

    His hospital is preparing to begin tests of a new, contactless system created by researchers at the EPFL polytechnical university in Lausanne and at the Swiss Center for Electronics and Microtechnology.

    The system designed in Switzerland should allow premature babies kept warm in incubators (恒温箱) to be medically monitored using highly sensitive cameras that detect the newborn's pulse by analyzing its skin color, which changes so slightly every time its heart beats.

    “Breathing is monitored by measuring movements of its chest and shoulders. At night, infrared (红外线的) cameras take over, and monitoring can be carried out non-stop,” the statement said.

    The visual system was designed by CSEM researchers, who chose cameras sensitive enough to detect minute changes in skin color, while the EPFL researchers designed algorithms (运算程序) to process the data in real time.

    “We ran an early study on adults, where we looked at a specific part of skin on their foreheads,” EPFL doctoral student Sibylle Fallet said. “With our algorithms we can track this area when the person moves, and use tiny changes in their color to determine the pulse,” she said. “The tests showed that the cameras produced practically the same results as conventional sensors.”

    Once the system has been widely tested on premature babies, it could one day replace skin sensors altogether, the schools said.

    In an effort to inform our citizens to clear the street snow, the city adopts a snow removal plan.

    Routes used by City Emergency Services come first. Secondly, connector streets will be cleared which allow citizens the greatest access to public roads. And thirdly, roads within neighborhoods will be cleared.

    Snow removal and ice control will start when:

    Snow accumulates 4 inches or more.

    Weather conditions do not endanger the safety of road crew.

    Snow falls during peak traffic periods of heavy use of main streets.

    Snow and ice removal will be delayed or cancelled when:

    There is severe cold, significant wind and limited visibility.

    The snowfall occurs on the weekend or a holiday and is not considered a threat to public safety. In that case, snow and ice removal may take place on the next normal weekday.

    Snow and ice may be left on roadways if melting is obvious.

    Your cooperation is requested during snow removal and these suggestions may apply:

    Limit travel during storms. Travel is possible once roads have been cleared or salted by the road crew

    Avoid removing snow from your driveway into the road. Pile the snow in your yard.

    Park your vehicles in your driveways and off the road or walks.

    Keep public sidewalks next to your house clear of snow and ice.

    Be responsible for removing this snow which is thrown by the snow plough(犁) from your driveways. Hopefully, you can understand this inconvenience.

    In China, chain restaurants especially the big multinational ones are cool. Going to Starbucks, for example, is a status symbol. It not only says, "I'm rich enough to buy this overpriced coffee, "but also, "I'm cosmopolitan (见多识广的) enough to be part of globalization."

    Where I come from in the UK, however, chains are neither fashionable nor gourmet (美食的). Chains are where you go on New Year's Day when nowhere else is open, or when you are 5 years old and your parents can't stand hearing, "I'm hungry!" any longer. In my own case (with regards to McDonald's), a chain is where you are taken on your first "date". Even at the age of 13, I knew to give the guy the "let's just be friends" phone call the next day.

    In the UK, independent cafes and restaurants are making a comeback on the fashion scene. Nowadays, a Londoner who says "let's meet for a coffee at Monmouth" (an independent café) is much cooler than one who says "let's go to Starbucks". Even if Monmouth's coffee is a little more expensive, there's a satisfaction in knowing your pounds aren't going straight to the big corporations.

    Of course, there are chain stores all over the UK; you can't go five minutes without spotting a Costa Coffee. But numbers do not add up to good taste.

    I do, however, have a confession (坦白). After moving to China I had moments when all the rice and Kung Pao Chicken became too much. I, too, have retreated to McDonald's.

As the pandemic makes clear, cities are possibly humanity's greatest invention, but cities with huge populations also make us easily suffer from the rapid spread of disease. Yet humans aren't the only species that face this problem. Honeybees have lived social lives for tens of millions of years, making them some of the most experienced in the battle against infection. And over time, natural selection has given them quite a few impressive strategies for reducing transmission within bee groups.

However, these strategies are not enough to prevent every threat. Honeybees are battling their own global disease, for which they were totally not prepared. A parasitic mite (寄生螨) originally existed only in the groups of Asian honeybees, but later jumped to infect Western honey bees. Today, it has spread to every region where honeybees are kept except Australia and a handful of remote islands, quickly becoming a global disease of the bees.

If left untreated, a group of bees will typically die from the mites within two years. These infections, plus farm chemicals and poor nutrition, have forced beekeepers to struggle to keep their bees alive. Of the 2.6 million honeybee groups in the US, over half of them have parasitic mite.

And that's only the count of those bees that are tested and reported; the actual numbers are likely much higher. Beekeepers have still managed to slowly increase the number of groups they keep, on average, but at a much higher cost.

Western honeybees did not grow with parasitic mite, and the Western bees lack the behavioral features those Asian honeybees have, like permanently burying the members infested by parasitic mite and, perhaps the most extreme strategy, where the bees are so sensitive to parasitic mite that they completely die as soon as infected, sacrificing themselves to prevent the mite from reproducing.