For the Travel section, writers and editors selected special items to profile from a dozen cities.

Brussels:Chocolate

    Nearly half the chocolate consumed in the world is eaten in Europe, and Belgium—with average consumption of 14.99 pounds per person a year—certainly covers its fair share. While Brussels, the country's capital, is home to hundreds of chocolate makers, what makes a visit necessary is the rich heritage of traditional chocolate makers.

Budapest: Paprika (红辣椒)

    The job of preparing Hungarian paprika was once considered too dangerous for mothers to do. A woman who touched her children upon returning from work risked burning them, so only the elderly and unmarried were allowed the delicate task of separating the skin from the flesh. But by the early 20^th century, sweeter varieties and a machine turned paprika into a common feature of all Hungarian cuisine.

Lisbon: Tiles (瓷砖)

    Is there a bluer Country than Portugal? The blue sky and Atlantic Ocean embrace the land. The blue moods of Fado, the dark folk music, form the national soundtrack. And all across Portugal, the typically blue designs of azulejos—ceramic tiles—are spread across churches, castles, palaces, university halls, parks... The result is a beautiful land of Christian saints, Portuguese kings, historical glories, aristocrats at leisure, seascapes and so on.

Madrid: Guitars

    Walking into one of Madrid's storied guitar makers' workshops can feel like stepping into the past. Curly wood shavings, from the palest pine to ebony, fall onto the floor as artisans turn some humble wood into works of art. It's painstaking work—all done by hand—with classical guitar models and the methods of making them changing little over the last century.

    Since 2008, hunters have illegally killed more than 3000 rhinos in South Africa. The International Union for Conservation of Nature warns that rhinos may die out by 2026. People who hunt and kill illegally are called poachers. The most effective way to watch for and prevent illegal hunting is from the air. However, piloted flights are too costly. Fortunately, some Spanish college students have invented a drone (无人机) that can observe more places than a plane.

    Arnau Garcia is an aeronautical (航空学的) engineering student at the Polytechnic Institute of Catalonia, in Spain. He says observers from the air have trouble finding poachers when they hide under the trees. Mr. Garcia and other students have worked with the drone manufacturer HEMAV to help find the hidden poachers. They make it by using the thermal camera, which is especially sensitive to body heat. Even when the poachers keep still, it can also keep track of them.

    The drone can fly in the wind up to 55 kilometers per hour. It has an autopilot system, so it memorizes the flight path. The drone also has a microphone, a video camera and a GPS system. These permit it to report accurately where a picture is taken. After each flight, the drone can bring back detailed information about where rhinos are found, the conditions of water and plants in the area, and the positions of suspected poachers.

    Experts say the drone can fly as far as 70 kilometers from the base. It means that it could quickly observe large areas for poachers. However, the same search operation would take days for human observers. Thanks to the drone, many poachers have been caught and the number of rhinos is on the increase. In addition, HEMAV has received an increasing number of orders for the drone. Even South African national park officials attempt to fill the air with drones.

    As the G20 Leaders Summit(峰会)kicked off on Sept 4, Hangzhou, the host city, took measures to promote its reputation for entrepreneurship(企业), as well as its many beauty sports, to those overseas people.

    Although many may have been surprised when Hangzhou was chosen to host the summit over bigger cities such as Beijing or Shanghai, economic statistics suggest that it's well deserving of the honor.

    When the national economy grew at 6.7 percent in the first half of this year, the lowest in more than two decades, Hangzhou steamed ahead with a huge 10.8 percent growth, becoming one of the only two cities in China, alongside Chongqing, with a double-digit growth rate.

Walking along the streets of Hangzhou, through centuries-old paths and along the Broadway—like Yan'an Avenue, a tourist can pick up whatever he or she wants with just a smartphone, via Alipay or WeChat Pay—no cash or credit cards needed.

    And starting this month, one can also rent public bikes simply by scanning the QR code(二维码)with a smartphone.

Meanwhile, a short video showing the beauty of Zhejiang Province and its capital, Hangzhou, was being aired on CNBC channels during prime time until Sept 12.

    The promotional video, created by CNBC's Catalyst Content Studio, highlighted some of Hangzhou's most charming attractions.

From eye-pleasing beauty spots like the Qiantang River and West Lake to the towering headquarters of leading Internet corporations, the promo(宣传片)showed how the city built its culture on a long history of commerce and developed into a vast modern center of technology, imports and exports.

    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.

    A conference was held with former technology industry leaders calling for urgent measures to protect children from smartphone addiction (上瘾).

    Among those urging major changes is Tristan Harris—a former high-level employee at Google. He just launched a group that will seek to gather and publish evidence of how digital devices and social media can harm children and young people. Harris says he believes companies like Google, Facebook and Apple have a "moral responsibility" not to create technology products that can "hijack how the mind works".

    The conference where Harris spoke was sponsored by Common Sense Media, a child and family activist group. The organization says research suggests that half of all teenagers feel addicted to their mobile devices, while about 60 percent of parents believe their kids are addicted.

    The group also cites a recent study of eighth graders that found heavy users of technology were 56 percent more likely to say they are unhappy, while 27 percent more likely to be depressed. Even Facebook cited research last year suggesting that social media use can harm mental health when used in certain ways.

    James Steyer is the founder of Common Sense. He says more than half of schools in the US are already members of the organization. The group provides teachers and parents with learning materials intended to help students develop critical thinking skills and balance their digital lives.

    Some US schools, however, have tried to limit or remove technology to improve learning. One of them is in Silicon Valley, the center of the American tech-industry.

    The Waldorf School of the Peninsula does not use any computers or digital technology in its education programs up to the seventh grade. The schools' website says while Waldorf teachers recognize the role technology can play in the classroom, it must wait until the student reaches the right developmental age. Normally when students reach high school, they are allowed to use computers and digital tools in the classroom.

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