I first came across the concept of pay-what-you-can cafes last summer in Boone, N.C., where I ate at F.A.R.M (Feed All Regardless of Means) Café. You can volunteer to earn your meal, pay the suggested price($10) or less, or you can overpay—paying it forward for a future customer's meal. My only regret after eating there was not having a chance to give my time. So as soon as Healthy World Café opened in York in April, I signed up for a volunteer shift(轮班).

    F.A.R.M and Healthy World are part of a growing trend of community cafés. In 2003, Denise Cerreta opened the first in Salt Lake City. Cerreta now runs the One World Everybody Eats Foundation, helping others copy her pay-what-you can model.

    “I think the community café is truly a hand up, not a handout,” Cerreta said. She acknowledged that soup kitchens(施粥所) have a place in society, but people typically don't feel good about going there.

    “One of the values of the community café is that we have another approach,” she said. “Everyone eats here, no one needs to know whether you volunteered, overpaid or underpaid.”

    The successful cafés not only address hunger and food insecurity but also become necessary parts of their neighborhood – whether it's a place to learn skills or hear live music. Some teach cooking to seniors; some offer free used books. Eating or working there is a reminder that we are all in this world together.

    My 10 am—1pm shift at World-Healthy-Café began with the café manager — one of the two paid staff members. Our volunteer crew wasn't the most orderly, but we managed to prepare and serve meals with a lot of laughs in between. At the end of my shift, I ordered my earned meal at the counter, together with other volunteers. After lunch, I walked out the door, with a handful of new friends, music in my head and a satisfied belly and heart.

    There is a breakthrough in building aircrafts. Bendable wings covered with overlapping(部分重叠) pieces resembling fish sizes could be used to build swifter, fuel-efficient aircraft, a new study finds.

    Nowadays, conventional aircrafts typically rely on ailerons (副翼) to help control the way the planes tip as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires and pulleys that twisted the wood-and-canvas wings, to control the plane.

    Scientists have long sought to develop aircrafts that can alter their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable, said Neil Gershenfeld, a physicist and director of the Center for Bits and Atoms at Massachusetts Institute of Technology (MIT).

    The new wing consists of a system of tiny, strong, lightweight modules. The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material resembling fish sizes. These strips move across each other as the wings alter, providing a smooth outer surface, the researchers explained.

    Wind-tunnel tests of these wings showed that they at least matched the aerodynamic properties of conventional wings, at about one-tenth the weight. Initial tests using remotely piloted aircrafts made with these wings have shown great promise, said Benjamin Jenett, a graduate student at the Center for Bits and Atoms at MIT.

    The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.

    “Still, the first aircraft built using this strategy will not be a passenger jet, ”Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircraft, leading to drones (无人机) that can fly for a long time, to help deliver internet access or medicine to remote villages and do some rescue works.”

    Most people who fly on passenger planes in the United States do not lose their luggage. Even if the luggage is lost, usually it is only delayed. Most “lost” luggage is found in a few days. Airlines search for the owners of unclaimed(未认领的) bags for up to three months. But when the owners cannot be found or the bags are not claimed, they are sold to a store in the small city of Scottsboro, in the southern state of Alabama.

    About one-half of one percent of all luggage passing through US airports is unclaimed. Many of the missing bags, and what is in them, are sold at the Unclaimed Baggage Center. Seven thousand items arrive at the store every day. Tom Barnes, who was shopping at the store said, “I can go into any of the large shopping centers, like the international malls. I can walk through there for an hour and come out with three items. But I come into this store, and then I come out with my car full of stuff.”

    Brenda Cantrell, who works at the store, said, “The Unclaimed Baggage Center is the only store in America that buys and resells unclaimed baggage from the airline industry. You would be surprised at all the jackets, eyeglasses, neck pillows, blankets, laptops, Kindles, iPads, and you know, all kinds of expensive electronics.”

    The store says it once sold a container for flowers for $80 that was found to be worth $18,000. And it says a painting it sold for $25 was later found to be worth $25,000.

    The store buys the luggage from the airlines. It does not examine the things inside them before buying them. Only about half of the items in the bags are suitable for sale at the store.

    Some people say it is not fair to the owners of the lost passage to sell their goods. Customer Daniel Martin is not one of them, saying, “I feel the airport may try to find the people that lose the things. If they've tried and they can't get a hold of them, it's better than throwing them away or just letting them rot in a warehouse somewhere.”

    A handsome man can earn a fifth more than a plainer colleague (同事) but a beautiful woman is not paid a penny more than her average-looking colleague, new research has shown.

    The study by senior economists (经济学家) found that being good-looking meant male workers could earn 22 percent more than average-looking colleagues. Researchers said good looks did not give women a similar advantage.

    Andrew Leigh, the former economics professor at the Australian National University who co-authored the report, said: "Beauty can be a double-edged sword for women."

    "Some people still believe good looks and intelligence (智慧) are incompatible (矛盾的) in women so a good-looking woman can't be that productive, but it doesn't affect men's pay."

He said that although he believed good-looking women may also earn more, the research did not support his theory.

    The research found that handsome men in all jobs, from manual labour to highly-paid professional careers, can earn 22 percent more than their colleagues doing the same work.

    Men with below-average looks face a battle in the office, with ugliness reducing a man's earnings by 26 percent compared to an average-looking worker.

    Former male model Ian Mitchell, 28, who has a first class degree in history from Edinburgh University and now works for a cosmetics (化妆品) company, told the Sunday Times: "It gives you confidence, and I suspect people tend to warm to you more quickly."

    The study, named Unpacking the Beauty Premium, was the largest exercise of its kind and repeated a survey from 1984 to see if the beauty premium had changed.

    Leigh said the research showed people in the workplace were "lookist (以貌取人的) " and he hoped the findings would encourage employers to remove their prejudice(偏见).

    Artificial Intelligence (AI) is making it possible for companies to monitor workers' behavior in great detail and in real time. Start to slack off (懈怠), and AI could talk to your boss.

    One company offering such services is London-based start-up Status Today. Its AI platform relies on a regular supply of employee data, including everything from the files you access to when you use a key card. From this, it builds a picture of how employees normally function and signals any unusual performance. The idea is to spot when someone might become a security risk by doing something different from their usual behavioral patterns. “All of this gives us fingerprint of a user, so if we think the fingerprint doesn't match, we raise a warning”, says Mircea Dumitrescu, the company's chief technology officer.

    The system also aims to catch employee actions that could accidentally cause a security breach (漏洞), like opening malware (恶意软件).“We're not monitoring if your computer has a virus.” says Dumitrescu. “We're monitoring human behaviors.”

    But catching the security breach means monitoring everyone, and the AI can also be used to track employee productivity. “It seems like they are just using the reputation of AI to give an air of lawfulness to old-fashioned workplace surveillance (监视),” says Javier Ruiz Diaz of digital campaigning organization the Open Rights Group. “You have a right to privacy and you shouldn't be expected to give that up at work.”

    Exactly how companies use the system will be up to them, but it's hard to shake the picture of an AI constantly looking over employees' shoulders. “It will bother people, and that could be counterproductive if it affects their behavior,” says Paul Bemal at the University of East Anglia.

    Phil Legg at the University of the West of England says it will never catch every security risk. “If people know they're being monitored, they can change their behavior,” he says.

    Before the 1830s most newspapers were sold through annual subscriptions in America, usually $8 to S10 a year. Today $8 or $10 seems a small amount of money, but at that time these amounts were forbidding to most citizens. Accordingly, newspapers were read almost only by rich people in politics or the trades. In addition, most newspapers had little in them that would appeal to a mass audience. They were dull and visually forbidding. But the revolution that was taking place in the 1830s would change all that.

    The trend, then, was toward the "penny paper" ­ a term referring to papers made widely available to the public. It meant any inexpensive newspaper; perhaps more importantly it meant newspapers that could be bought in single copies on the street.

      This development did not take place overnight. It had been possible (but not easy) to buy single copies of newspapers before 1830, but this usually meant the reader had to go down to the printer's office to purchase a copy. Street sales were almost unknown. However, within a few years, street sales of newspapers would be commonplace in eastern cities, At first the price of single copies was seldom a penny ­ usually two or three cents was charged ­ and some of the older well-known papers charged five or six cents. But the phrase "penny paper" caught the public's fancy, and soon there would be papers that did indeed sell for only a penny.

    This new trend of newspapers for "the man on the street" did not begin well. Some of the early ventures were immediate failures. Publishers already in business, people who were owners of successful papers, had little desire to change the tradition. It took a few youthful and daring businessmen to get the ball rolling.