Whatever life threw at us each year, our family had one tradition at Christmas: our dog Pepper opened our presents for us.

    Last year, everyone made it home for a Christmas get-together. However, it couldn't feel perfect because Pepper's health was becoming worse. Her life had already been longer than we expected-she was fourteen-and yet her mind was still sharp. Her love for life made us feel better. But her body could not keep up with her mind.

    Probably it was Pepper's last Christmas, so we decided to make sure she would enjoy it. On Christmas Eve, we each prepared presents for her.

    Soon, Pepper selected her first Christmas gift. She turned the present, just as she was a young dog once more. She pulled the paper off the dog treat before she chewed (咀嚼) it slowly. Our family was so happy.

    Pepper saw the remaining three presents, and then turned to Mom as if asking, “May I open another?”

    “Go ahead, girl!” Mom encouraged.

    For the next few minutes, Pepper opened each of her Christmas presents. While she did, she reminded us of the joy of being together. Our family felt as a whole-not because we were in the same room or city, but because our love brought us together.

    Pepper passed away after Christmas. Her peaceful passing made us tearful. Her passing was also a celebration of life, because she gave my family so much love and laughter.

    I still treasure Pepper's final Christmas gift. She taught me that no matter where we each spend the holidays, the smallest act of sincere giving can unite our family through our love. For me, that knowledge is the longest-lasting gift of all.

    As self — driving cars come closer to being common on American roads, much of the rhetoric (说辞) promoting them has to do with safety. About 40,000 people die on U. S. roads every year, and driver errors are linked to more than 90 percent of crashes. But many of the biggest advocates of autonomous vehicles aren't car companies looking to improve the safety of their existing products. Huge backing for self - driving technologies is coming from Silicon Valley giants like Google and Apple.

    Those of us who have studied the relationship between technology and society tend to look more carefully at the motivations behind any technological push. In this case, it's clear that in addition to addressing safety concerns, Silicon Valley firms have a strong incentive (动机) to create a new venue for increasing the use of their digital devices. Every minute people spend on their mobile phones provides data - and often money - to tech companies.

    At present, digital devices and driving are in conflict: There are serious, often fatal, consequences when drivers use smartphones to talk or to text. Regulators and safety advocates look to resolve dial conflict by banning phone use while driving - as has happened in virtually every state. But the tech companies are taking a different approach. The obvious answer for Silicon Valley is creating an antomobile in which continuous cellphone use no longer poses a threat to anyone.

    In recent years, the amount of time adults spend on their mobile devices has grown rapidly. At the moment, it's around four hours a day for the average adult in the U. S. However, that rapid growth is likely to slow down as people run out of time that ' s available for them to use their devices. Unless, of course, there's a new block of time that suddenly opens up. The average American now spends about 48 minutes in a car every day, a sizable opportunity for increased cellphone use.

    So as the public conversation around autonomous cars highlights the safety advantages, don't forget the tech industry ' s powerful desire for more profits, which goes well beyond simply saving us from ourselves.

    On Friday, the Food and Drug Administration (FDA) released two proposals to improve food safety. The regulations are a response to a series of recent foodborne illnesses. The FDA hopes these new rules will prevent problems of food in the earliest period of production, before the contaminated（受污染的）food causes consumers to get sick.

    Over the past decade, foodborne illnesses have caused many people to get sick. Food like spinach（菠菜）, ground beef and cantaloupes（甜瓜）has been sent back to producers, because it is bound to contain germs and bacteria that cause illnesses.

    Among the most common problems are dangerous bacteria that cause stomach pains and food poisoning. Often these illnesses occur when food is undercooked or improperly prepared. While not all illnesses are reported, the FDA estimates that nearly 130,000 Americans a year are hospitalized for food-related problems.

    The two new rules proposed by the FDA are called Preventive Controls for Human Food and Standards for Produce Safety. Each rule is described in detail on the FDA's website. Readers can submit comments, which the FDA will use as feedback to mike future adjustments to the proposals.

    The first rule demands manufacturers should have formal plans for preventing contamination and for fixing problems when contamination occurs. This regulation is applied to food produced in the US and overseas.

    The second rule k specific to food that is eaten raw. It requires strict standards of growing harvesting, and packing fruit and vegetables. Workers must make sure the materials used in soil are safe and free of contamination.

    The FDA believes these new rules will not just improve Americans' health but also make a positive economic impact. The regulations can lead to major savings in medical costs for people who get sick because of the contamination food.

    If manufacturers are able to fix problems at source, they will prevent future issuer However, putting the proposals into action will lake lime and money.

    With her pretty face and soulful voice, Zhang Bichen was thought a possible champion when she first set foot on the stage of the TV show The Voice of China.

    On Oct 7, 2014, the 25-year-old girl won the fierce competition and received the title of the “Voice of the Year”. Zhang's dream of being a singer star came true as last. What impressed people was not only Zhang's singing skills, but her willingness to make an effort. “I gained the opportunity to sing on The Voice of China,” she said.

    In fact, being a singer has always been her dream. She wanted to apply to a college for singing, but her parents insisted that she should have an easy job after graduation because she did very well at school. So Zhang gave in to her parents and learned French at university. However, in the first year of her college, she was discovered by a South Korean company when she entered a singing competition. To realize her dream, Zhang signed a contract（合同）with the company, started her career in South Korea, and became a member of a band.

    “My company had rules that did not allow us to use cell phones. During the first few months after I arrived in South Korea, a totally unfamiliar country, I felt terribly homesick. But I could only phone my parents in the restroom when nobody noticed.” Zhang said. “When I did not have much income, I had to eat noodles every day for months.”

    It was her positive attitude and outgoing character that helped her through. “When I feel down, I tell myself it is not winning or losing that matters. The most important things are standing on the stage and singing for people.” she said.

    If your dog looks pleased to see you—it is probably because it loves the particular way you smell.

    The scent (气味)of a familiar human apparently lingers like perfumein the animal's brain—where it causes an instinctive emotional response, research reveals.

    Our scent acts on a part of the canine (犬科的) brain associated with reward and the strongest reactions are produced by humans that pets know best, say scientists in America.

    Gregory Bern, of Emory University in Atlanta, said, “While we might expect that dogs should be highly tuned to the smell of other dogs, it seems that the 'reward response' is reserved for their humans. When humans smell the perfume of someone they love, they may have an immediate, emotional reaction that's not necessarily cognitive (认识的). So is it in dogs. But since dogs have a more sensitive smell than humans, their responses would likely be even more powerful than the ones we might have. In our experiment, however, the owners of the dog were not physically present. The canine brain responses were being caused by something distant in space and time. It shows that dogs' brains have these mental representations of us that persist when we're not there.”

    The experiment involved 12 dogs of various kinds by brain scans while five different scents were placed in front of them. The scent samples (样本)came from the subject (接受试险者) itself, a dog the subject had never met, a dog living in the subject's household. The familiar human scent samples were taken from someone else from the house other than the handlers during the experiment, so that none of the scent donors were physically present.

    The results showed all five scents gained a similar response in parts of the dogs brains involved in detecting smells. Responses were significantly stronger for the scent of familiar humans, followed by that of familiar dogs. The findings showed dogs reacted strongest to the scent of familiar humans even when they were not there. Pets trained as help or therapy dogs showed greater brain activity than the other dogs in the test.

    Researchers say the findings could improve the way to select animals helping wounded old soldiers or disabled people.

    Alexa is a form of artificial intelligence, or AI for short. Many people start their mornings by asking Alexa for the weather forecast or the latest news. A device(设备) that houses Alexa can also play music from your favorite playlists, keep a shopping list, order takeout food, answer questions, send messages and even run “smart” home controls.

    Training AI systems to respond to problems with human-like intelligence and learn from their mistakes can take months, or even years. Consider Alexa and similar software, such as Apple's Siri. To do the tasks its human owners ask, these systems must make sense of and then respond to sentences such as, “Alexa, play my Ed Sheeran playlist” or “Siri, what is the capital of India?”

    Computers can't understand language as it is spoken by people. So AI researchers must find a way to help humans communicate with computers. The technology used to get computers to “understand” human speech or text is known as natural language processing. By natural language, computer scientists refer to the way people naturally talk or write. To teach an AI system a task like comprehending(理解) a sentence or responding to a person 's last move in a board game, scientists need to feed it lots of examples.

AlphaGo is an AI system designed by Google that has beaten a human champion, Lee Sedol, at the strategy(策略) board game Go. To train AlphaGo, Google had to show it 30 million Go moves that people had made while playing the game. Then AlphaGo used what it learned to analyze those plays as it played against different versions (版本) of itself. During this practice, the program came up with new moves—ones never seen in games between people.