Against the assumption that forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.

    This finding suggests that taking steps to prevent northern forest fires to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over next several centuries as a result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.

    This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.

    Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone（臭氧）levels increased, and ash from the fire fell on far-off sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.

    “We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere.” Scientists tracked the change in amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicated, 0.5 watts per square meter of area burned are soaked up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.

    Everyone should be so lucky as to have a friend like Francia Raisa. On Thursday, singer and actress Selena Gomez, 25, used Instagram to explain why she was “laying low” this summer. She posted a photo of herself in a hospital bed with her friend Francia Raisa holding hands. She said she recently received a kidney transplant from her best friend because of complications（并发症）from lupus（狼疮）, an autoimmune disease, which means it is the result of the immune system attacking normal tissue, including the kidneys, brain, heart and lungs.

    People with lupus may first experience tiredness, joint pain or a little bit of rash（皮疹）on their bodies and can go for a long time before their doctors realize it is more serious. Many people see two or four doctors before the real problem is picked up. According to Dr. Kyriakos Kirou, roughly a third to one-half of people with lupus develop kidney disease, and up to one in five of them will eventually need a transplant, sometimes because they weren't treated with effective drugs to prevent the immune system from attacking the kidneys. Though Gomez said that she was “very well now,” she warned about the dangers of not taking medical diagnoses seriously, like she initially did.

    Her Instagram post also called attention to two major health topics: the need for living organ donators and the fact that Gomez represents three groups more likely to be diagnosed with lupus and lupus-related kidney disease. Nine out of 10 people diagnosed with lupus are women, and most develop the disease between the ages of 15 to 44. And lupus is two to three times more common among women of color, including Hispanic women, according to the Lupus Foundation.

    Raisa is Latina, and Gomez's father is of Mexican origin. While it's not essential that the organ donator and receiver be of the sane ethnicity, people who share a similar background sometimes are better matched, according to data from the United Network for Organ Sharing.

    Peter Skyllberg, a Swedish man, was trapped in his car for two months, with temperatures reaching -30^oC, with no food or water, and yet he survived. The best explanation was that his vehicle created an “igloo (snow house) effect” and protected him from the extremely low temperatures and that his body would hibernate(冬眠) during this time.

    Can humans get into a low-energy consumption state like a bear by reserving energy, and reducing body temperature? Chinese scientists are looking for the key to regulating body temperature.

    Scientists have found the hypothalamus (下丘脑), an area in the central lower part of the brain, is responsible for regulating body temperature. Wang Hong, a brain scientist at the Shenzhen Institutes of Advanced Technology of the Chinese Academy of Sciences, led her team to mark the neurons (神经元) responsible for regulating body temperature in mice by means of a cutting-edge genetic biology technique. In the experiments, they injected (注射) drug into mice to make the body temperatures of the mice drop rom 37℃ to 27 in two hours. The team found the change in body temperature caused no harm to the health of the mice. “We don't know if we can develop a drug that can control human body temperature. We still need a lot of study.” Wang said.

    Chinese scientists are not alone in such research. Body-cooling techniques are being used in pioneering hospitals around the world. Dutch doctors are now using low temperatures for patients who have suffered brain injuries in accidents, According to doctors working in Florence, it may even help to save the brains of babies who are born suffering from severe epileptic fits (癫痫病发作).

    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 voice-activated digital assistant, while robots are deployed to serve dishes, cocktails and coffee. Hotel bookings and check-out can also be done with a few clicks on mobile through an app. The Al-based 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 companies1 attempt into traditional industries such as the hotel industry.

    E-commerce 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 QQ family, 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."

    Marathon fever is sweeping this country. In recent years, China's ever-growing passion for marathons has been triggered by its economic development and health-conscious middle class. A large number of marathon runners are white-collar workers, civil servants and business people that are keen on leading a healthy lifestyle. Government support, social participation and strong marketing by the sports industry have gradually led to the rapid development of the marathon industry, which is currently valued at 70 billion yuan ($10. 77 billion). Due to its large participation and nationwide media report, marathons are considered by local governments an important part of marketing their cities. Thus, many cities list unique routes across local scenic spots and historical attractions, not only to boost people's fitness, but also to promote local tourism.

    For many runners, marathons are a way of life." As we get older, the places and opportunities to meet new people decrease. I find that participating in marathons is a simple way to make friends," said Wu, who made many friends in the Xstop Running Community, a running club with 48, 000 members established by Xtep, one of the leading distributors of sports merchandise in China.

    "The sense of belonging and the mutual encouragement that exists within the running community are very attractive to many people. We easily befriend one another, since we have the same goal: to keep running and never stop," Wu said. Besides, a marathon can be a great way to explore new places. For a runner who also loves traveling, marathons are a solid choice. "Competing in an international marathon is a chance to experience a city or a country you've never visited before," said Meng, an experienced runner from north China's Tianjin Municipality, who often runs in London, New York and Melbourne.

    There's a unique perspective that people get running through the streets of a city, distinct ancient buildings or amazing natural settings, he explained, things that somehow just can't be seen by rushing in a car. In addition, during a race, streets are often closed off so you don't have to battle traffic.

    Large gatherings such as weddings and conferences can be socially stressful. Pressure to learn people's names only adds to the stress. A new facial-recognition app could come to the rescue, but privacy experts recommend going on with caution.

    The app, called SocialRecall, connects names with faces via smartphone cameras and facial recognition, potentially avoiding the need for formal introductions. "It breaks down these social barriers we all have when meeting somebody," says Barry Sandrew, who created the app and tested it at an event attended by about 1,000 people.

    After receiving an invitation to download SocialRecall from an event organizer, the user is asked to take two selfies and sign in via social media. At the event, the app is active within a previously defined geographical area. When a user points his or her phone camera at an attendee's face, the app identifies the individual displays the person's name, and links to his or her social media profile. To protect privacy, it recognizes only those who have agreed to participate. And the app's creators say it automatically deletes users' data after an event.

    Ann Cavoukian, a privacy expert who runs the Privacy by Design Center of Excellence praises the app's creators for these protective measures. She cautions, however, that when people choose to share their personal information with the app they should know that there may be unintended consequences down the road with that information being used in another context that might come back to bite you."

    The start-up has also developed a version of the app for individuals who suffer from prosopagnosia, or "face blindness", a condition that prevents people from recognizing individuals they have met. To use this app a person first acquires an image of someone's face, from either the smartphone's camera or a photograph, and then tags it with a name. When the camera spots that same face in real life, the previously entered information is displayed. The collected data are stored only on a user's phone, according to the team behind the app.