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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    Guide Dogs of America, A History is the book that we all have been waiting for. It's a book that tells how and where the guide dog movement really started, with information never before revealed--until now. After reading this 200-page, picture-filled work, you will know about every aspect of Guide Dogs of America(GDA) from its inception to how it has become one of the top guide dog schools in the country.

    Joseph W. Jones, Sr., was refused a guide dog because of his age--he was fifty seven--but he would not accept defeat. He researched the guide dog movement and with the help of the International Association of Machinists and Aerospace Workers, established his own school, one that would provide guide dogs free of charge to visually impaired people regardless of their age.

    The school graduated 18 guide dog teams the first year with students staying at, GDA's first trainer, Lambert Kreimer's house on South Virginia Avenue in Burbank, and Jones manning the office on Lankershim Boulevard in North Hollywood.

    In 1952, Jones addressed the quadrennial(四周年纪念的) IAM Grand Lodge Convention in Kansas City, Missouri. “I sincerely prayed to God for two things,” Jones said. “After my wife passed away and left me with a ten-year-old boy, I prayed that I would be spared long enough to see this organization well established and that my ten-year-old boy would become a man. Both prayers have been answered. The organization is well established, it is in the hands of the IAM and my boy is a man, and I am proud to say that today he is a member of the IAM.”

    Jones' pray for a successful organization had been answered now, ten years after he was rejected for being too old, his dream of having a guide dog for himself, hundreds of others had already been given the gift of sight because of his drive and determination. That school, now known as Guide Dogs of America, has provided guide dogs to thousands of people free of charge.

    72-year-old Darlene Mullins recently graduated from Tennessee State University in Nashville, Tennessee. Darlene left school nearly 55 years ago in the name of love. She was studying at the college and met her husband-to-be, John Mullins, in 1962. The two knew they would marry each other the moment they met. She finished her freshman year with 25 credits and married John in 1963. Her husband graduated in 1964 and began working.

    Darlene took care of the household and was a stay-at-home mother to their son and daughter. The family lived in six states over the years, due to John's successful career in business. Darlene eventually began a career in retail as their children grew older. Though she remained busy, she always longed to finish school. She always told her children to make sure they finish what they started and she kind of felt it was time to live up to her own dream.

    John was very supportive when she told him she was going back to school. He knew the day would come when she decided to finish her degree. He told her whenever she was ready they would go. The couple moved back to Nashville in 2013 when Darlene re-enrolled. She had to adjust to the technological advances in the classroom, saying that she was determined to finish no matter how long it took. After completing four years, Darlene graduated with a degree, “I feel like God has given me a second chance.” she said' She hopes that her story can inspire others to pursue a degree.

The hardest thing about planning a big European vacation is actually narrowing down where to go—there are just so many amazing places. That's why we've put together what we think are the best cities in Europe. 

AMSTERDAM, NETHERLANDS

Amsterdam is the kind of city that you can't help but fall in love with. It's the kind of place where you dream about moving and buying an apartment that overlooks (俯瞰) a peaceful river. It's relaxing and you get a sense that the locals have an amazing quality of free life. We love simply walking around the canals and exploring the city's neighborhoods. 

BERLIN, GERMANY

Berlin is said to be "poor but charming" and we think that's a pretty good description. Actually, Berlin is becoming more expensive as its popularity grows, but it's still the top spot for Germany's artistic scene. Berlin isn't particularly pretty but it's an energetic city with cool people and cooler graffiti-covered (涂鸦) neighborhoods. 

LISBON, PORTUGAL

Lisbon is a hot destination and I doubt it will be quickly moving up in the ranks of Europe's most visited cities. Lisbon is a popular coastal city that's famous for its unique buildings and charming café culture. It's also very friendly on the wallet when compared to other Western European cities—food and lodging are both priced reasonably and attractions are about average. 

FLORENCE, ITALY

Florence may be touristy but that's no reason to ignore this birthplace of the Renaissance (文艺复兴). If you do your research, you can find plenty of excellent Italian restaurants and world-class ice cream. And, of course, the city is beautiful and home to top museums so it's a dream for art and history lovers.

For eight-year-old Toby, who is deaf, watching films or TV can sometimes be a bit pointless, because so many of them don't have sign language versions. "We have subtitles but it goes too fast," his dad Jarod Mills said. But now, Toby has some help thanks to an app developed by a 17-year-old student, Mariella Satow, who created a signing app called SignUp.

She got the idea when she was teaching herself American Sign Language(ASL)—one of hundreds of sign languages used across the world. Manella wanted to watch TV shows to help her learn, and she was disappointed to discover how few had signed versions. It's taken a year for Mariella to develop the technology, with lots of help from ASL teachers and the deaf community.

The app is available in the US as a browser extension—with an interpreter appearing in a box once the film starts playing. It only works on Disney Plus films at the moment, because that's where Mariella thought she could help the most children. Jarod, who works at a school for deaf children, says it was "exciting" watching Toby use Mariella's invention. He says, "Kids are getting information like any hearing child does."

Deaf people in the UK face many of the same barriers when it comes to cinema and TV. "A hearing person can go to the cinema any time whereas deaf people have to make sure there's a suitable viewing a time we're free," says 27-year-old Stacey Worboys from Cardiff. She has learned British Sign Language(BSL), and is comfortable using subtitles when watching TV shows and films. But she feels having an interpreter would make things "more inclusive", especially for someone who might struggle with subtitles. Stacey and Toby aren't the only people to be welcoming Mariella's app. It's now got thousands of users.

Stacey says a UK version of an app like SignUp would make films and TV "more accessible" for the deaf community. Mariella is up for the challenge—and hopes to make a British Sign Language version of her app for other streaming platforms such as Netflix and Amazon Prime. "There are more than 300 sign languages used worldwide, so it'll take a long time to get all of those versions out," she says.

Brilliant Ways to Deliver Secret Messages

Many effective ways are used now to deliver secret messages. But in the past when the science and technology was not developing, especially during the war, how did people send secret and important messages?

Shoelaces

In the 1950s, the U.S. Central Intelligence Agency created a book of tips to teach spies ways to communicate in public. One tip: Lace up your shoes. Tied one way, the laces might mean "I have information": tied another, "Follow me". The spies could communicate while everyone else probably thought, "That guy can't tie his shoes correctly!"

Tattooed (刺文身) Head

Around 513 B.C., Histiaeus was forced out as the ruler of an ancient city. So he wanted to send a message to his supporters: Rebel against the king who took away his power.

Histiaeus called in a slave, shaved his head and tattooed the message onto the man's skin on the top of head. After the slave's hair grew back, he travelled to Greece with orders to shave his head again. Message received!

Orange Juice

In 1597, John Gerard was imprisoned in the Tower of London in England. He asked the prison guard to let him send letters written in charcoal (木炭). But then he wrote another message on top using the juice from an orange-which was only visible when the juice was dry and the page heated. With his invisible ink, he escaped successfully.

Songs

In the 1800s, African American slaves couldn't talk openly about their plans to escape to freedom—so they secretly sang about it.

Swing Low, Sweet Chariot might sound like a religious song. But for slaves, the "sweet chariot" was the code for the Underground Railroad, the network of people who helped slaves head to northern states and Canada. The song Wade in the Water warned escaped slaves to get in the water so dogs wouldn't smell them. With these songs, hundreds of people escaped slavery.