On a Saturday morning earlier this September, the world got its first look at the Strati. This electric vehicle is unlike any other currently on the road. It rolls on four wheels, but its body and chassis(底盘) weren't built in a factory. Instead, Strati's designers used a technology called 3-D printing. It created those parts of the car in one piece, from the ground up.

    “Compared to a typical vehicle on the road, the Strati definitely looks different,” says Greg Schroeder, a senior research engineer at the Center for Automotive Research in Ann Arbor, Mich. He did not work on the new car. His organization studies trends and changes in th e auto industry.

    It took 44 hours to print the new car at the International Manufacturing Technology Show in Chicago. Over the next few days, the car's designers installed additional parts. These included the car's engine, brakes and tires. Then, early on September 13, Jay Rogers climbed into the car, started its engine and drove the vehicle onto the street. Rogers helped found Local Motors. It's the Arizona-based company behind the Strati. Two weeks later, his team printed a second Strati, and just as fast, at a fair in New York City.

    Justin Fishkin, a local Motors official, sees the Strati as a window into the future. Today, car buyers are limited in their choice of a vehicle. They can order only what car companies have already designed. But in the future, he says, you may be able to design your own car online and then get it printed to order.

    Manufacturing experts say 3-D printing has begun to revolutionize how they make things. The technology has been around for decades. But these machines used to be so expensive that only large companies could afford them. In the last few years, though, that has changed. Many of the machines are now inexpensive enough for small companies—or even individuals —to own. Some local libraries make them available to the public. High Schools are beginning to use them in classrooms. Wide access to these printers means people can now design and print a wide variety of new things.

    The car's printer is a one-of-a-kind device.

    The technology behind the 3-D printer used in Chicago is an example of additive manufacturing. This proce ss builds solid objects, slice by slice, from the bottom up. (“Strati” means layers, in Italian.) A mechanical arm moves a nozzle from one side to another, back and forth. As it moves, the nozzle deposits a liquid—often melted plastic or metal (but it could be food, concrete or even cells) —that quickly hardens or bonds to become solid or semi-solid. This creates a single, thin layer. Once a layer is complete, the printer starts depositing the next one.

    “There's a lot of interest in 3-D printing in the auto industry,” says Schroeder. Right now, the technology is particularly useful for building models of cars or car parts.

    To compete with current auto manufacturers, the 3-D printer would have to increase in a hurry, Schroeder says. By contrast, he notes, a Ford F-150 pickup truck rolls off an assembly line at a rate of roughly one per minute. To print as many Stratis would require many more printers. Schroeder says he doesn't see 3-D printing soon taking over for such high-volume manufacturing. But, he adds, “Who knows what will h appen in the long term?”

    Scientists at Oak Ridge National Laboratory in Tennessee designed the 3-D printer used in Chicago. Lonnie Love, a research scientist at the lab, led the effort.

    Additive manufacturing often is slow and expensive. It also may produce materials that are unreliable, Love says. So for two years, his team searched for ways to make 3-D printing better. They built new machines and tested them over and over.

    All of that work paid off: their new machine is fast and uses less expensive material than earlier printers. In addition, it prints a plastic embedded with fibers of carbon to produce a stronger material. This helps ensure the material won't crack or break under pressure.

    Nothing could stop Dad. After he was put on disability for a bad back, he bought a small farm in the country, just enough to grow food for the family. He planted vegetables, fruit trees and even kept bees for honey.

    And every week he cleaned Old Man McColgin's chicken house in exchange for manure(肥料).The smell really burned the inside of your nose. When we complained about the terrible smell, Dad said the stronger the manure, the healthier the crops, and he was right. For example, just one of his cantaloupes filled the entire house with its sweet smell, and the taste was even sweeter.

    As the vegetables started coming in, Dad threw himself into cooking. One day, armed with a basket of vegetables, he announced he was going to make stew(炖菜).Dad pulled out a pressure cooker and filled it up with cabbages, eggplants, potatoes, corns, onions and carrots. For about half an hour, the pressure built and the vegetables cooked. Finally, Dad turned off the stove, the pot began to cool and the pressure relief valve sprayed out a cloud of steam. If we thought Dad's pile of chicken manure was bad, this was 10 times worse. When Dad took off the lid, the smell nearly knocked us out.

    Dad carried the pot out and we opened doors and windows to air out the house. Just how bad was it? The neighbors came out of their houses to see if we had a gas leak!

    Determined, Dad filled our plates with steaming stew and passed them around. It didn't look that bad, and after the first wave had shut down my ability to smell, it didn't offend the nose so much, either. I took a taste. It would never win a prize in a cooking competition, but it was surprisingly edible, and we drank up every last drop of soup!

Whenever the sun dropped and the blue sky came up, my father and I used to climb the mountain near my house. Walking together, my father and I used to have a lot of conversations through which I learned lessons from his experiences. He always told me, "You should have goals like climbing the mountain. " without the mountain-climbing that we both enjoyed, we couldn't have enough time to spend together because my father was very busy. I really got a lot from mountain-climbing. It gave me time to talk with my father and to be in deep thought as well as develop my patience.

Once we climbed a very high mountain. It was so challenging for me because I was only ten years old. During the first few hours of climbing, I enjoyed the flowers and trees, and the birds'singing, but as time passed, I got a pain in both of my legs. I wanted to quit climbing. In fact, I hated it at that mountain, but my father said to me, "You can always see a beautiful sky at the top of the mountain, but you can't see it before you reach the top. Only there at the top can you see all of the nice things, just like in life. "

    At that time, I was too young to understand his words. But later after that, I got new hope and confidence. I found myself standing at the top of the sky, which was as clear as crystal.

    An open office is supposed to force employees to cooperate. To have them talk more face to face. To get them off instant messenger (IM) and brainstorming new ideas. But a recent study by two researchers offers evidence to support what many people who work in open offices already know: It doesn't really work that way. The noise causes people to put on headphones and tune out. The lack of privacy causes others to work from home when they can. And the sense of being in a fishbowl means many choose email over a desk-side chat.

    Ethan Bernstein and Stephen Turban, two Harvard Business School professors, studied two Fortune 500 companies that made the shift to an open office environment from one where workers had more privacy. Using “sociometric” electronic badges (徽章) and microphones, as well as data on email and instant messenger use by employees, the researchers found in the first study that after the organization made the move to open-plan offices, workers spent 73% less time in face-to-face interaction. Meanwhile, email use rose 67% and IM use went up 75%.

    The participants wore the badges and microphones for several weeks before the office was redesigned and for several after, and the company gave the researchers access to their electronic communications. The results were astonishing. “We were surprised by the degree to which we found the effect,” Bernstein said. The badges could tell that two people had a face-to-face interaction without recording actual spoken words. The researchers were careful to make sure other factors weren't in question—the business cycle was similar, for instance, and the group of employees were the same.

    In a second study, the researchers looked at the changes in interaction between specific pairs of colleagues, finding a similar drop in face-to-face communication and a smaller but still significant increase in electronic correspondence.

    Another wrinkle in their research, Bernstein said, is that not only did workers shift the way of communication they used, but they also tended to interact with different groups of people online than they did in person. Moving from one kind of communication to another may not be all bad—“maybe email is just more efficient,” he said—but if managers want certain teams of people to be interacting, that may be lost more than they think. The shift in office space could “have strong effects on productivity and the quality of work”.

    Bernstein hopes the research will offer evidence that will help managers consider the possible trade-offs of moving to an open office plan. In seeking a lower cost per square foot, they buy into the idea that it will also lead to more cooperation, even if it's not clear that's true. “I don't blame the architects,” he said. “But I do think we spend more of our time thinking about how to design workplaces based on the observer's angle”—the manager—“rather than the observed.”

    Your local grocery store is a psychological minefield (布雷区), where even the bananas are ripe with mystery.

    ⒈Southpaws (左撇子) have an invisible advantage

    You've probably seen that stores keep go-to items produce, meats, dairy on the outer edge. But did you notice that most of them are set up to make you run counterclockwise (逆时针)? Ninety percent of us are right-handed, so we buy more when it's counterclockwise. You'll also often find the dairy section in the back-left corner: Because dairy is likely on your list, stores make sure you take the longest route to get there. In fairness, it's also a more convenient place to put a fridge.

    ⒉Everything is in its place

    It's safe to say that nothing you see on a shelf is there by chance. The cookies on sale at the end of a passage are likely the result of smart product placement. More expensive items are usually placed at an adult's eye level, while colorful treats and other products for kids are positioned lower to catch the attention of children.

    ⒊Time goes by so slowly

    Stores rarely have windows or clocks. With no reference to the outside world, customers can easily lose track of how long they've been there so that they can buy more. Grocery stores may use another trick to control your sense of time: small floor tiles (瓷砖).

    A family in Florida had a happy Christmas this year thanks to two local police officers, who answered a 911 call only to discover there was no emergency at all.

    When they arrived at the house of a single mother with two children, the officers discovered the younger child, about two years old, was playing with the phone. There were no signs of Christmas or holiday cheer in the house. "They weren't smiling. It seemed like they weren't happy at all. They were missing something," Officer Paramore said. "The mother mentioned that they weren't going to have a Christmas that year. It was pretty obvious that the family was struggling," he said. "So we told each other that something had to be done."

    Paramore and his partner, Barry Ward, left the house with a plan. The next day, they went to a supermarket and bought a tree, lights and some ornaments (装饰物) with their own money. Then they returned to the apartment to deliver some holiday cheer. "They hugged the tree," Paramore said. "I was glad to see that this family was going to have something to sit around and use." The police department posted the video on YouTube, hoping to share the happy news and inspire others.

    The department has received tons of donations and phone calls from people around the country asking how they can help the family. "We are covered," said Stephanie Slater, public information officer for the Boynton Beach Police Department. "We're asking people to do good in their communities on behalf of our officers. We appreciate it very much that people are talking about this after watching the news on TV because they need to see and need to be reminded that police officers are good guys," she said. "They are human beings who have a kind heart and they do things that go unnoticed like this every day."