Amazon is breaking into physical retail in a new way. The online retail giant revealed a new kind of physical store concept in a video published on Monday.

    The store, called Amazon Go, doesn't work like a typical Walmart or supermarket. Instead, it's designed so that shoppers will use an app, also called Amazon Go, to automatically add the products that they plan to buy to a digital shopping cart by scanning a QR code(二维码). They can then walk out of the building without waiting in a checkout line because Amazon will charge their Amazon account and send them a receipt.

    The first Amazon Go store is located in Seattle, where Amazon is headquartered. For years, there have been rumors the e-commerce company would expand its dominance from digital to physical shopping. Amazon began experimenting with physical bookstores a year ago, but Amazon Go may mark its boldest bet on physical ones yet. By removing much of the staff needed to operate a store, Amazon keeps costs lower than traditional competitors. It's also in a strong position to bring together data on its customers' shopping habits online and offline to make better suggestions in all situations.

    However, Amazon's move deeper into physical retail shops comes in a sensitive political climate. The company could be perceived as being a threat to some of the 3.4 million Americans who work as cashiers, according to the Bureau of Labor Statistics. On the campaign trail, Donald Trump repeatedly criticized Amazon and its founder Jeff Bezos for “getting away with murder tax-wise” and having “a huge antitrust(反垄断) problem.” Will the President& shy; elect add “job killer” to the list of criticisms?

    Amazon's effort to launch a new kind of retail store predates(在……之前) the rise of Donald Trump. “Four years ago we asked ourselves: what if we could create a shopping experience with no lines and no checkout? Could we push the boundaries of computer vision and machine learning to create a store where customers could simply take what they want and go?” The company says on an informational page about Amazon Go. For now, Amazon is starting slow. The Amazon Go is only open to Amazon employees in our Beta program, and is scheduled to open to the public in early 2017.

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    Stephen Hawking, the brilliant British theoretical physicist who published wildly popular books exploring the mysteries of the universe, has died, according to a family spokesman. He was 76.

    Considered by many to be the world's greatest living scientist, Hawking was also a cosmologist, astronomer, mathematician and author of numerous books including the landmark“A Brief History of Time,” which has sold more than 10 million copies.

    With fellow physicist Roger Penrose, Hawking combined Einstein's theory of relativity with quantum theory(量子理论) to suggest that space and time would begin with the Big Bang and end in black holes. He also discovered that black holes were not completely black but emit(释放) radiation and would likely eventually evaporate(蒸发) and disappear. “It will be difficult enough to avoid disasters on planet Earth in the next 100 years, let alone next thousand, or million. The human race shouldn't have all its eggs in one basket or on one plant. Let's hope we can avoid dropping the basket until we have spread the load.”

    Hawking suffered from ALS (amyotrophic latcral sclerosis), a disease which is usually fatal within a few years. He was diagnosed in 1963, when he was 21, and doctors initially gave him only a few years to live. The disease left Hawking wheelchair-bound and paralyzed. He was able to move only a few fingers on one hand and was completely dependent on others or on technology for everything—bathing, dressing, eating, even speech. “I have been lucky that my condition has progressed more slowly than is often the case. But it shows that one need not lose hope.” Dramatically, he even guest-starred in the “Star Trek”, “The Simpsons” and the 2014movie “The theory of Everything”.

    Hawking leaves behind three children and three grandchildren. “We are deeply saddened that our beloved father passed away today,” Hawking's children, Lucy, Robert and Tim, said in a statement. “He was a great scientist and an extraordinary man whose work and legacy will live on for many years. His courage and persistence with his brilliance and humor inspired people across the world. “We will miss him forever.”

    If doctors want to test you for something, they'll usually take a blood or urine sample. But wouldn't it be much more convenient if they just asked you to breathe through a special instrument?

    In fact, your breath can say a lot about you. In traditional Chinese medicine, doctors draw a conclusion about the health state of a patient based on the smell of his or her breath; trained dogs and rats can identify the smells of the breaths of people suffering from certain cancers; traffic police also monitor drivers' alcohol consumption by testing their breaths.

    Just like blood and urine, your breath contains lots of “metabolites” —the waste chemicals that the body produces, which vary from person to person. They are like personal health fingerprints, which is why scientists sometimes call them “breathprints”, according to Science Daily.

    Compared to blood or urine testing, breath testing takes only seconds instead of hours, and it requires neither a needle nor a container to hold the body fluids(液). This means the test can be taken frequently to better detect early signs of diseases and monitor the progress of a medical treatment.

    On the other hand, as an identifier, you might think that breaths are not as reliable as fingerprints since they might change based on what you eat. However, researchers in Zurich, Switzerland mapped 11 healthy volunteers' chemical patterns by having them breathe through a special instrument, and they found that each pattern was unique and the patterns didn't change much throughout the day, reported BBC.

    “Our goal is to develop breath analysis to the point where it becomes competitive with the established analysis of blood and urine,” said Malcolm Kohler, professor at the University Hospital Zurich.

    There's a warm and wonderful tradition that the British observe on December 26. It's called Boxing Day.

    For many people, Christmas can be a magical day filled with delight. But for those down on their luck or the disadvantaged, it can be a time of sorrow and disappointment. That's why the British have set aside the day after Christmas as Boxing day, and its purpose is to bring a bit of magic to those who could use it

    Every December 26, going at least as far back as the 1830s, the United Kingdom and other countries that are part of the British Commonwealth(英联邦) such as Canada, Australia, New Zealand and India, have observed Boxing Day as an opportunity to provide some holiday joy for those who most need it.

    There are competing stories behind the name boxing Day. One is that it refers to the giving of "Christmas boxes", a term that started in the 17th century to describe gifts, money and the leftovers from Christmas that lords of the manor(庄园)would give to their servants and employees for having worked on Christmas Day. Basically, "Christmas boxes" were holiday bonuses(奖金) for the working class.

    The other is that it refers to the "contribution boxes" that would traditionally appear in charities in the weeks leading up to Christmas for the purpose of collecting money from donators that charity staff would distribute to those in need after Christmas Day.

    The day is still a national holiday in many parts of the British Commonwealth, and while people still give something back to people who have bad luck or give tips to service people on Boxing Day, it has also become a major shopping day like Black Friday in the U.S.

    Brian Hamilton's life changed in a prison when he was accompanying his friend, Reverend Robert J. Harris, who often went to local prisons to do his work. During the visit, Hamilton started talking to one of the prisoners and asked what he was going to do when he got out.

    "He said he was going to get a job," Hamilton recalls(回忆). "I thought to myself, wow, that's going to be difficult with a criminal background."

    The conversation made Hamilton consider how prisoners could benefit from entrepreneurship, something he thought about for years. Finally in 2008, 16 years after that initial conversation, Hamilton created Inmates to Entrepreneurs, a nonprofit organization that helps people with criminal backgrounds start their own small businesses. "Harris and I taught our first course at a prison called 'How to Start Your Own Business When You Get Out'," he recalls.

    At the time, Hamilton was building his own company, Sageworks. As Sageworks grew, so did Hamilton's time spent teaching at prisons throughout North Carolina.

    Eventually, Hamilton decided it was time to change his focus to his true passion. In May 2018, he sold his stake(股份) in Sageworks, focusing his commitment on Inmates to Entrepreneurs.

    "Now, anyone is able to access the curriculum, either to become an instructor to go into prisons to teach it or to access it for themselves as a prisoner or part of the general population," Hamilton explains. In addition, he visits middle schools and presents the curriculum to at-risk students as a preventative measure against crime.

    The free curriculum is funded by the recently established Brian Hamilton Foundation, which offers assistance to military members as they adjust to civilian life and provides loans to small businesses. "We're giving prisoners something they can do independent of a system that isn't working for them. If you can let people know that other people care about them, it makes a difference."

    When young, I loved going on trail(小路) runs. It was my favorite way to escape stress. So, when I was back in my hometown after a tough first year of my Ph. D. program, I thought a trail run was just what I needed. But instead of helping me relax, the run did just the opposite.

    After I moved to the city for college, where my runs were on flat concrete paths instead of winding dirt trails, I used a GPS watch. When I went on trail runs again in the country, it constantly reminded me of the fact that I wasn't keeping up with my usual pace. I turned my watch off, thinking that would allow me to enjoy my surroundings and find the peace I expected, but I worried I was underperforming. "Why can't I let go and just enjoy myself?" I wondered. But after some introspection(反省), I realized why I was struggling­both on trail runs and in graduate school.

    Going into my Ph. D. , I had thought that my solid undergraduate track record would set me up for instant success. To my surprise, I was wrong. I lacked confidence in my research abilities which I thought stopped me performing well and I constantly felt my progress was too slow. Other students'self-confidence and their excellent results made me feel insecure. Finally, one day I broke down in tears in my adviser's office.

    Then came my visit home: I was having trouble because I hadn't properly adjusted my expectations to the differences between an urban run and a trail run.

    A Ph. D. is like a trail run: Sometimes you can run fast. Sometimes you might find yourself climbing up a steep, winding trail at a snail's pace. And that's OK. Barriers are unavoidable, and success looks and feels different on a challenging trail than it does on a smooth, flat path. Sometimes it's best to take a deep breath and do your best to meet the challenge.