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.

Rafting the GRAND CANYON Welcomes You!

    For an exciting，fun and challenging white water tours，Rafting the GRAND CANYON is here to help you plan the right tour for you. Whether you want to travel for two days or ten，hike in or not，go on an oar raft or motorized trip，we will help you find the trip that meets your needs.

    For those who will be vacationing on the off­season a trip on the Native American Red River rafting is available year around or a one ­day trip is available on the Colorado River from Diamond Creek to Pierce Ferry (about three hours from Las Vegas)．

    Most of the trips depart from Lees Ferry，Arizona (approximately 21/2 hours from the south rim of the Grand Canyon)．We offer partial trips which allow you to get on or off at Phantom Ranch located at the bottom of the Grand Canyon National Park South Rim. Requiring a hike in or out，with proper planning the horse ride up or down is also an option. Most trips occur between April and October.

    Since all rafting on the Colorado requires a permit，planning and reserving your trip requires reservations well in advance. Please let us know when you would like to go and we will contact all the river concessionaires (特许权获得者)to help you find the best trip for you.

    For planning your trip，questions，concerns or to make your reservations，please email or call the toll free number below. Since these trips are limited we highly recommend you make your reservations months in advance.

    To talk to a live person call us toll free：1­800­222­6966 or 702­655­6060

    If you have any questions regarding a trip，please CLICK_HERE to fill out our form. This will speed up the process of getting you accurate information regarding your trip.

    If you would like to send us an email other than about an up­coming trip you can contact us at info@raftingthegrandcanyon.com.

    We look forward to helping you plan your trip! (Please NO Travel Agents)

    For anyone still doubting the belief that our emotions influence our physical health, a new study from New Zealand should be able to settle the matter. It reports that the physical wounds of healthy seniors healed more quickly if they wrote about their most upsetting experiences.

    This confirms the results of a 2010 study, and extends those findings to cover older adults—a group that is likely to suffer wounds (as from surgery), and one with less access to other ways of lowering tension (such as exercise).

    Reported in the journal Psychosomatic Medicine, a research team led by the University of Auckland's Elizabeth Broadbent made a study featuring 50 healthy adults ranging in age from 64 to 97. They were asked to write for 20 minutes per day for three consecutive (连续的) days.

    Half were asked to write about the most upsetting experience in their life, describing their deepest thoughts, feelings, and emotions about the events, ideally not previously shared with others. The others were asked to write about their daily activities without mentioning emotions, opinions or beliefs.

    Two weeks after the third day of writing, all participants received a standard 4mm skin biopsy (皮下活体组织检查) on their inner arm. The very tiny wounds caused by the biopsy were photographed regularly over the following days to determine the rate at which they healed.

    On the 11th day after the biopsy, the wounds completely healed on 76.2 percent of those who had done the expressive writing. That was true of only 42.1 percent of those who had written about everyday activities.

    “The biological and psychological mechanisms (机体) behind this effect remain unclear,” the researchers wrote, noting that those who had done the expressive writing did not report lower stress levels or fewer depressive symptoms than the others in the control group. Even if they weren't consciously aware of feeling more relaxed or positive, the expressive writing appeared to have caused some sort of bodily reaction—probably involving their immune systems—that hastened their recovery.

    A new argument has been put forward as to whether penguins are disturbed by the presence of tourists in Antarctica.

    Previous research by scientists from Keil University in Germany monitored Adelie penguins and noted that the birds' heart rates increased dramatically at the sight of a human as far as 30 meters away. But new research using an artificial egg, which is equipped to measure heart rates, disputes this. Scientists from the Scott Polar Research Institute at Cambridge say that a slow moving human who does not approach the nest too closely, is not viewed as a threat by penguins.

    The earlier findings have been used to partly explain the 20 per cent drop in populations of certain types of penguins near tourist sites. However, tour operators have continued to insist that their activities do not adversely（不利地）affect wildlife in Antarctica, saying they encourage non-destructive behavior in tourists, and that the decline in penguin numbers is caused by other factors.

    Amanda Nimon of the Scott Polar Research Institute spent three southern hemisphere summers at Cuverville Island in Antarctica studying penguin behavior towards humans. “A nesting penguin will react very differently to a person rapidly and closely approaching the nest,” says Nimon. “First they exhibit large and prolonged heart rate changes and then they often flee the nest leaving it open for predators（掠夺者）to fly in and remove eggs or chicks.” The artificial egg, specially for the project, monitored both the parent who had been 'disturbed' when the egg was placed in the nest and the other parent as they both took it in turns to guard the nest.

    However, Boris Culik, who monitored the Adelie penguins, believes that Nimon's findings do not prove his own research invalid. He points out that species behave differently – and Nimon's work was with Gentoo penguins. Nimon and her colleagues believe that Culik's research was methodologically（方法论上）defective because the monitoring of penguins' responses needed catching the birds and fitting them with heart-rate transmitters（发射器）. Therefore, argues Nimon, it would not be surprising if they became stressed on seeing a human subsequently.

    When you watch a movie these days, it's difficult to tell what's real and what's created by using computers. Visual effects can even change how movies are made.

    Almost anything that can be imagined by a director can now become reality in the world of movies. "We're really not limited by the technology, '' said David Smith, the CEO of Sony Pictures Imageworks. Mr Smith said that with today's technology, the digital world was more realistic than ever before. For The Amazing Spider-Man 2, Mr Smith's team created a Times Square that was exactly like the real one in New York. "If there are lights inside the stores that are lighting areas inside the store we put those lights there," said Mr Smith.

    But there was still one challenge for visual effects artists, said Paul Debevec of the University of Southern California Institute for Creative Technologies. "We're still trying to figure out how to perfect the human face in movies, " said Debevec. He said the movie — The Curious Case of Benjamin Button was still one of the best examples of computer generated movies, as actor Brad Pitt could be from an aged man to a baby in the movie.

    Mr Debevec added that besides changing the look of an actor's face, there could be another use for digital faces in the entertainment. Last year, effects artists created a digital face of the Asian pop singer Teresa Teng who was dead. Fans could still see and hear the concert on YouTube.

    Mr Debevec expects directors will start to use more virtual production techniques, like those seen in the movie Avatar. Mr Debevec says that with virtual production, there won't be a need for so many people behind the scenes. But visual effects artists agree, even with advanced technology, there is no replacement for a real actor showing a character in a movie.

We are all stuck in the thought of having satisfying relationships, which bring some meaning to our lives and make us happy. We are so busy in finding true happiness that we often forget true happiness lies within us.

You have to love yourself first in order to love someone else. We have heard in countless inspiring speeches that self-love is the basis of a happy life. Have you ever wondered that with so many people advertising self-love, why haven't we been able to love ourselves?

One of the reasons for our failure to love ourselves is that we have been taught to be selfless from the start of time. The minute we start thinking about ourselves, everyone around us makes it their personal mission to remind us of how selfish we are. However, there is nothing wrong with putting your needs and yourself first. Self-love is not selfish. It only helps us better understand which sacrifices (牺牲) are worth making!

Actually, self-love and healthy relationships cannot be separated. Self-love is the very core of any healthy relationship. Now you might wonder how my love for myself is going to make me able to have a healthy relationship. Isn't a healthy relationship all about giving? Honestly, No.

When you know your worth, you know what you are willing to accept in a relationship and what not. You will know where to draw boundaries because you value your own opinions. You will have a clear understanding of what you need, what are your values and your limits. From now on, you should realize that true happiness lies within you and you shouldn't waste time and effort searching for peace and joy in the world outside.