A ground-based system that uses much stronger signals than GPS can find your location in cities and indoors. It is a new positioning system that could compete with GPS to make sure you never lose your directions again.

    Instead of satellites, Locata uses ground-based equipment to send a radio signal over a localized area that is a million times stronger on arrival than GPS. It can work indoors as well as outdoors, and the makers claim that the receivers can be shrunk(缩小) to fit inside a regular cell phone. Even the US armies, which invented GPS technology, signed a file last month agreeing to a test of Locata at the White Sands Missile Range in New Mexico.

    “This is one of the most important technology developments for the future of the positioning industry,” says Nunzio Gambale, CEO and co-founder of the firm Locata, based in Griffith, Australia.

    As for the Locata's correctness, Christopher Morin of the US Air Force tested it recently at White Sands, and it worked to within 18cm along any axis(轴). Morin said it should be possible to get the exactitude down to 5cm.

    The tests were performed in an open desert where GPS also worked beautifully, but its signal was weak—like a car headlight from 20,000 kilometers away—and easily cut off by solid objects(实心的物体). Locata's signal was far stronger, though not guaranteed to work in a complex urban environment, said David, speaker of the UK' s General Lighthouse Authorities.

    Locata's technology will face competition in the race to transform indoor navigation. But it could shine in specific areas, Gambale said. Robots with Locata could easily navigate inside buildings without the complex optical(视觉的) systems they need at the moment. And the process that handles correct location data could not only guide you around a mall, railway station or airport, but also take you to the exact shelf in a shop for the product you want. It would be small and cheap enough for smart phones and it should be available within five years—a similar path to the one GPS took on its way towards the world, he said.

    Make A Difference Day is the largest national day of community service in the USA, which takes place on the fourth Saturday of October.

    Who takes part in Make A Difference Day?

    Anyone! Young and old, individuals and groups, anyone can carry out a volunteer project that helps others. It might be as ambitious as collecting truckloads of clothing for the homeless, or as personal as spending an afternoon helping an elderly neighbor or relative. USA WEEKEND covers volunteers and their projects in articles and photos.

    How do I get started?

    Look around your community. Are people hungry, homeless or ill? Are parks or schools dirty or neglected? No matter where you live, there's a need nearby. And on Make A Difference Day, millions of Americans are expected to roll up their sleeves to help others. You can act alone or enlist your friends, family and co-workers. You can also call the Make A Difference Day Hot Line, 1-800-416-3824, for information. Or use the ideas on this website for inspiration.

    What do I do after I've selected a project?

    Tell others what you're doing and enlist help. Several weeks before the day, tell us about your plans in the Make A Difference DAYtaBANK, a national listing of local projects that will be viewed by interested volunteers, other people looking for good project ideas and news media looking for good stories to tell. It will only take a few minutes to post your plans in the DAYtaBANK hosted by HandsOn Network.

    Do it!

    Carry out your plans to help others on Make A Difference Day. Be sure to take lots of pictures and share them on the Make A Difference Day Photo Album.

    People tend to become more personal and hide less of themselves when using email. Researchers from Open University in Britain have found in a recent study that there are good reasons for this.

    The team of researchers asked 83 pairs of students, all strangers to each other, to solve a problem. They had to discuss this question: If only five people in the world could be saved from a world disaster, who should they be? The pairs of students had to talk over the problem either face to face or by computers. Dr. Johnson said, “They told their partners four times as much about themselves when they talked over the Internet as when they talked face to face. When the computers were fitted with cameras so that students could see each other, this limited the personal side of the conversation.”

    Generally the information was not extremely personal. It was mainly about things such as where they went to school, or where they used to live. But some students discussed their love stories, and personal childhood experiences.

    Dr Johnson believes that emailing encourages people to focus on themselves. And when they do this, they become more open, especially if there are no cameras. “If you cannot see the other person, it becomes easier to talk about yourself. This is because you are not thinking what the other person is thinking of you. So emailing has become the modern way of talking,” said Dr. Johnson. However, this style of talking is not entirely new. “In the 19th century people started to use the ‘telegraph' to communicate. Now the same kind of thing has happened and people ended up speaking more freely.”

    Dr. Johnson thinks that emailers need to know about these effects of emailing, especially when they start work in a company. “ If you don't know about them, you could find yourself saying more about yourself than you wanted to.”

    When people ask me to name typical British dishes,I have,however,struggled to think of an answer.Yes,we do have our own national dishes.We do have fish and chips,and we have other dishes like roast dinner and shepherd's pie.But how much do we actually eat them?

    Fish and chips,is made up of battered（绞碎的）fish and chips,which is often accompanied by a thick paste（酱）. The majority of British people really do love this dish but it is not something that we would eat,say,on a weekly basis.It's also not usually something that we would cook at home.The British people associate this dish with the seaside and it's something that will usually be eaten on a day trip there,bought from a takeaway fish and chip shop.

    Another favourite British dish is roast dinner.This is made up of roast meat,usually chicken or beef, accompanied by roast vegetables and a meat sauce called gravy（肉汁）.It is usually eaten on a Sunday,perhaps for a special family dinner.It can either be cooked at home or eaten in a traditional pub.We also eat a more elaborate version of this for our Christmas dinner.

    Although we do have our traditional dishes,our diet has been greatly influenced by other countries.You can find a wide range of international foods in the supermarket or varieties of different restaurants on our high streets.A famous saying amongst British people is that our national dish is now chicken tikka masala,a dish which is heavily influenced by Indian cuisine.

    Don't expect to be served a traditional dish if you ever get invited for dinner at a British family's home!

    Durian(榴莲) is probably the smelliest fruit in the world, letting out an unusual unpleasant smell which would make anyone bring up. However, nobody was aware of what gave this fruit its unique smell, so a team of researchers from Singapore decided to take a look at its genome (基因组) and find out,

    Durian is well-known throughout Southeast Asia as the king of fruits, mostly because of its awful appearance and smell. However, the origin of this unpleasant smell was unknown, so researchers decided to map the genome of the fruit, and find the gene that controlled it. A group of genes, volatile sulfur compounds (含硫化合物), became very active in the fruit, and they were found responsible for resulting in the unpleasant smell.

    The fruit confuses everyone with a sulfuric smell, like rotten onions and ingredients. The smell lasts long, mostly because the fruit contains more volatile sulfur compounds. Other species usually benefit from two gene copies at most, but durian has four, leading to the striking smell.

    However, this smell might be an advantage for durian in the wild. Although we find it unpleasant, many animals might be attracted by it. If they eat the fruit, then they can easily spread its seeds everywhere, thus contributing to the distribution of the species.

    The mapping of the durian genome also showed some other information on the species. First of all, the fruit has an impressive number of genes, namely 46,000. Also, with the help of these genes, they saw how it evolved, and discovered it was related to the cacao tree. All the other discoveries have been published in the journal Nature Genetics.

    Despite the striking smell, many people actually enjoy eating the fruit. However, not all durian species are edible, and some of them may even cause damage to our health, Even so, the fruit is often imported, significantly contributing to the economy.

    One of the qualities that most people admire in others is the willingness to admit one's mistakes. It is extremely hard sometimes to say a simple thing like "I was wrong about that," and it is even harder to say, "I was wrong, and you were right about that."

    I had an experience recently with someone admitting to me that he had made a mistake fifteen years ago. He told me he had been the manager of a certain store in the neighborhood where I grew up, and he asked me if I remembered the egg cartons (in many countries, eggs are sold by the dozen and are put in cartons.) Then he related an incident (event, matter) and I began to remember unclearly the incident he was describing.

    I was about eight years old at the time. I went into the store with my mother to do some shopping. On that particular day, I must have found my way to the food department where the incident took place.

    There must have been a special sale on eggs that day because there were lots of eggs in dozen and half-dozen cartons. The cartons were put three or four feet high. I must have stopped in front of the piles of egg cartons. Just then a woman came by pushing her shopping cart and knocked off the cartons. For some reason, I decided it was up to me to put the eggs back together, so I went to work.

    The manager heard the noise and came rushing over to see what had happened. When he appeared, I was on my knees looking at some of the cartons to see if any of the eggs were broken, but to him it looked as though I was the one who just did it. He severely reprimanded me and wanted me to pay for any broken eggs. I tried to explain, but it did no good. Even though I quickly forgot all about the incident, it is plain that the manager did not.