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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    Try this: For an entire day, forget about the clock. Eat when you're hungry and sleep when you're tired. What do you think will happen?

    You may be surprised to find that your day is much like most other days. You'll probably get hungry when you normally eat and tired when you normally sleep. Even though you don't know what time it is, your body does.

    These patterns of daily life are called circadian rhythms, and they are more than just habits. Inside our bodies are several clocklike systems that follow a roughly 24-hour cycle. Throughout the day and night, our internal clocks direct changes in temperature, body chemicals, hunger, sleepiness and more.

    Everyone's rhythms are unique, which is why you might like to stay up late while your sister always wants to go to bed early. But overall, everyone is programmed to feel tired at night and energetic during the day.

    Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal（内部的） clocks. Now, new discoveries are giving scientists insights into how these clocks work.

    Learning about our body clocks may help scientists understand why problems arise when we act out of step with our circadian rhythms. For example, traveling across time zones can make people wake up in the middle of the night. Regularly staying up late can make kids do worse on tests and quizzes. And working shifts at night leads to higher rates of heart disease, diabetes and obesity.

    “There is a growing sense that when we eat and when we sleep are important parts of how healthy we are,” says Steven Shea, Director of the Sleep Disorders Research Program at Brigham and Women's Hospital in Boston.

    Scientists still aren't sure why the timing of sleep matters so much, Shea says. But research findings suggest that our circadian rhythms are more important than we give them credit for.

    “During the night, we are prepared to sleep,” Shea says. “During the day, we are prepared to eat and move around. If you reverse (颠倒)what you are doing, everything is out of phase. That can have unfavorable consequences.”

    Venom (毒液) from a local scorpion (蝎子) in Cuba is being used by Cuban scientists as an effective weapon to fight cancer. The venom, with stopping pain, anti-inflammatory (炎症) and anti-cancer properties, is the active ingredient in the medicine “Vidatox 30 CH,” which can be used to treat liver, brain, lung and other cancers. The treatment has been successfully used for more than four years in humans after being first tested in biological models. Labiofam, a Cuban laboratory, has breeding (繁殖) centers for both the Red Scorpion and Blue Scorpion. Each month, some 30,000 scorpions in Las Minas town, 270 km east of Havana are made to give the venom. After two years, the scorpions are released back into their natural habitat.

    Denyer Sanchez, a biologist from Labiofam, explained that the conditions are adjusted for reproduction, proved by the high number of breeding female scorpions. He said when the offspring (后代) becomes able to live in the environment, we release them because they do not have the necessary size yet to remove their venom, said Sanchez. Sanchez also said that there is still much to research on the exploitation process of scorpions, such as female death rate or the ability to survive of the released scorpions.

    Cuban research on the scorpion's venom began at the end of 1980s in Guantanamo province, the island's eastern tip, where a group of biologists and doctors became interested in the stories told by the peasants about the venom's benefits. However, the first discovery was made by Cuban biologist Misael Bordier. In 2001, Bordier visited Mexico's National Autonomous University (UNAM) and presented the research progress in a professional journal. Bordier died in 2005, one year before Cuba's Industrial Property Office gave Labiofam the rights to exploit the patent related to the venom.

    Congratulations on having been offered, and accepting, a place to study at Cambridge! This page offers some tips that will hopefully make your arrival at Cambridge as stress-free as possible.

    Before you arrive

    Your College or Department will send you all the information you need to prepare yourself for your time in Cambridge, including College information, for example, accommodation, course information, and similar related details. You will be sent an email asking you to complete the University's Student Registration exercise. It will only take a few minutes.

    Pre-arrival Freshers' Events this summer

    Around the world in August and September, Cambridge Alumni（毕业生）Groups will be hosting pre-arrival Freshers' Events for new students coming to Cambridge this autumn. These events are a great opportunity to prepare for university and make some friends before you arrive. There will be the chance to meet current students and alumni from whom you can get tips and advice for living and studying in Cambridge.

    Arrival and registration

    Most courses start in October. The term between October and December is known as Michaelmas Term in Cambridge. Officially, the first day of the Michaelmas Term is 1 October and this date will be shown on your offer letter. Your College or your Department will advise you about when to arrive. Ceremony activities begin around 1 October for most students. When you arrive in Cambridge, you should go first to your College. They will be glad to know that you have arrived safely and will advise you on what to do next.

    Matriculation

    Matriculation marks the formal admission of a student to membership of the University, and a College may not normally allow an unmatriculatied student to be a resident member of the College. Every freshman for matriculation must agree with the following belief by signing the Matriculation Registration Form:

    I promise to observe the Statutes and Ordinances of the University as far as they concern me, and to pay due respect and obedience to the Chancellor and other officers of the University.

Some people today might be early risers because of DNA they take after Neanderthals tens of thousands of years ago, suggests new research.

When early humans migrated from Africa to Eurasia roughly 70, 000 years ago, some of them mated with Neanderthals, who had already adapted to the colder, darker climates of the north. The ripple(涟漪) effects of that inter mating still exist today：Modern humans of non-African ancestry(血统) have between 1 and 4 percent Neanderthal DNA. Some of that DNA relates to sleep more specifically, the internal body clock known as the circadian rhythm.

For the new study, researchers compared DNA from today's humans and DNA from Neanderthal fossils(化石) .In both groups, they found some of the same genetic variants involved with the circadian rhythm. And they found that modern humans who carry these variants also reported being early risers.

For Neanderthals, being "morning people" might not have been the real benefit of carrying these genes. Instead, scientists suggest, Neanderthals' DNA gave them faster, more flexible internal body clocks, which allowed them to adjust more easily to annual changes in daylight. This connection makes sense in the context of human history. When early humans moved north out of Africa, they would have experienced variable daylight hours—shorter days in the winter and longer days in the summer-for the first time. The Neanderthals' circadian rhythm genes likely helped early humans' offspring(后代) adapt to this new environment.

Notably, the findings do not prove that Neanderthal genes are responsible for the sleep habits of all early risers. Lots of different factors beyond genetics can contribute, including social and environmental influences. The study also only included DNA from a database called the U.K. Biobank-so the findings may not necessarily apply to all modern humans. Next, the research team hopes to study other genetic databases to see if the same link holds true for people of other ancestries. If the findings do apply more broadly, they may one day be useful for improving sleep in the modern world, where circadian rhythms are disturbed by night shifts and glowing smartphones.