When I was 12, all I wanted was a signet (图章) ring. They were the "in" thing and it seemed every girl except me had one. On my 13th birthday, my Mum gave me a signet ring with my initials(姓名首字母) carved into it. I was in heaven.

    What made it even more special was that it was about the only thing that wasn't being "replaced". We'd been burnt out in fires that swept through our area earlier that year and had lost everything—so most of the " new" stuff (东西) we got was really just to replace what we'd lost. But not my ring. My ring was new.

    Then, only one month later, I lost it. I took it off before bed and it was missing in the morning. I was sad and searched everywhere for it. But it seemed to have disappeared. Eventually, I gave up and stopped looking for it. And two years later, we sold the house and moved away.

    Years passed, and a couple of moves later, I was visiting my parents' when Mum told me that she had something for me. It wasn't my birthday, nor was it Easter or Christmas or any other gift-giving occasion. Mum noticed my questioning look. " You'll recognize this one," she said, smiling.

    Then she handed me a small ring box. I took it from her and opened it to find my beautiful signet ring inside. The family who had bought our house 13 years earlier had recently decided to do some redecorations, which included replacing the carpets. When they pulled the carpet up in my old bedroom, they found the ring. As it had my initials carved into it, they realized who owned the ring. They'd had it professionally cleaned up by a jeweler before sending it to my mother. And it still fits me.

    Since the 1970s, scientists have been searching for ways to link the brain with computers. Brain-computer interface (界面) (BCI) technology could help people with disabilities send commands to machines.

    Recently, two researchers, Jose Milan and Michele Tavella from the Federal Polytechnic School in Lausanne, Switzerland, demonstrated（展示）a small robotic wheelchair directed by a person's thoughts.

    In the laboratory, Tavella operated the wheelchair just by thinking about moving his left or right hand. He could even talk as he watched the vehicle and guided it with his thoughts.

    “Our brain has billions of nerve cells. These send signals through the spinal cord (脊髓) to the muscles to give us the ability to move. But spinal cord injuries or other conditions can prevent these weak electrical signals from reaching the muscles,” Tavella says.  “Our system allows disabled people to communicate with external world and also to control devices.”

    The researchers designed a special cap for the user. This head cover picks up the signals from the scalp(头皮) and sends them to a computer. The computer interprets the signals and commands the motorized wheelchair. The wheelchair also has two cameras that identify objects in its path. They help the computer react to commands from the brain.

    Prof. Milan, the team leader, says scientists keep improving the computer software that interprets brain signals and turns them into simple commands. “The practical possibilities that BCI technology offers to disabled people can be grouped in two categories: communication, and controlling devices. One example is this wheelchair.”

    He says his team has set two goals. One is testing with real patients, so as to prove that this is a technology they can benefit from. And the other is to guarantee that they can use the technology over long periods of time.

    Light travels at a speed which is about a million times faster than the speed of sound. In one second, light travels about 300,000 km, but sound travels only 344m. You can get some idea of this difference by watching the start of a race. If you stand some distance away from the Starter, you can see smoke come from his gun before the sound reaches your ears.
     This great speed of light produces some strange facts. Sunlight takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays (光线) left the moon 1.3 seconds before they reached you. The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km per minute. In some cases the light from one of tonight's stars started on its journey to you before you were born.

    Thus, if we want to be honest, we cannot say “The stars are shinning tonight.” We have to say, “The stars look pretty. They were shining four years ago but their light has only just reached Earth.”

    For more and more young Chinese professionals, the first day back at work after the Lunar New Year holiday is the day they quit.

   The period after the Lunar New Year holiday, also known as Spring Festival, often sees Chinese workers on the move. This year, the number looking for new opportunities is supposed to be especially high.

    Mr. Zhu, a 27-year-old Beijing native, is one of the young workers looking for a better deal. “Salary is a big concern for me and I need a job that pays more, and my department can't provide good career development for me,” he said.

    An online survey by Zhaopin.com, a leading job-hunting website, provides further details on why China's young white-collar workers are so keen to move on.

    Low salaries are the biggest concern for 62% of the job-hunters, and overtime and a wide mismatch between low salaries and high housing costs are also the complaints. Two-thirds of them said they had to work at home after office hours, and a full 95% said they felt they were under heavy pressure because of the housing payment or rent.

    The survey also found that what was seen as a “good job” has changed. For the generation born in the 1970s, high salary and status is the key. For the generation born after 1980, work-life balance and respect in the office are also important.

    Zhao Bin, a 28-year-old woman who earns over 7,000 yuan a month working at a public relations company in Shanghai, said she would wait until the Lunar New Year to change her job. “My salary is OK for me, but I am working like crazy. So I want to find something comfortable, like being an English teacher in training schools.”

    Technology is always trying to meet our needs and demands. There's a new frontier in 3D printing that's beginning to come into focus: food. Recent development has made possible machines that print, cook and serve foods on a mass scale. And the industry isn't stopping there.

    Food production

    With a 3D printer, a cook can print complicated chocolate sculptures and beautiful pieces for decoration on a wedding cake. Not everybody can do that — it takes years of experience, but a printer makes it easy. A restaurant in Spain uses a Foodini to "recreate forms and pieces" of food that are "exactly the same," freeing cooks to complete other tasks. In another restaurant, all of the dishes and desserts it serves are 3D-printed, rather than farm to table.

    Sustainability (可持续性)

    The global population is expected to grow to 9.6 billion by 2050, and some analysts estimate that food production will need to be raised by 50 percent to maintain current levels. Sustainability is becoming a necessity. 3D food printing could probably contribute to the solution. Some experts believe printers could use hydrocolloids (水解胶体) from plentiful renewables like algae (藻类) and grass to replace the familiar ingredients (烹饪原料). 3D printing can reduce fuel use and emissions. Grocery stores of the future might stock "food" that lasts years on end, freeing up shelf space and reducing transportation and storage requirements.

    Nutrition

    Future 3D food printers could make processed food healthier. Hod Lipson, a professor at Columbia University, said, "Food printing could allow consumers to print food with customized nutritional content, like vitamins. So instead of eating a piece of yesterday's bread from the supermarket, you'd eat something baked just for you on demand."

    Challenges

    Despite recent advancements in 3D food printing, the industry has many challenges to overcome. Currently, most ingredients must be changed to a paste (糊状物) before a printer can use them, and the printing process is quite time-consuming, because ingredients interact with each other in very complex ways. On top of that, most of the 3D food printers now are restricted to dry ingredients, because meat and milk products may easily go bad. Some experts are skeptical about 3D food printers, believing they are better suited for fast food restaurant than homes and high-end restaurants.

    I have learned something about myself since I moved from Long Island to Florida three years ago. Even though I own a home in Port St. Lucie just minutes from the ocean, an uncontrollable urge wells up to return to Long Island even as others make their way south. I guess I am a snowbird stuck in reverse. Instead of enjoying Florida's mild winters, I willingly endure the severe weather on Long Island, the place I called home for 65 years.

    I'm like a migratory bird that has lost its sense of timing and direction, my wings flapping against season.

    So what makes me fly against the tide of snowbirds? The answer has a lot to do with my reluctance to give up the things that define who I am. Once I hear that the temperature on Long Island has dipped into the range of 40 to 50 degrees, I begin to long for the sight and crackling sound of a wood fire. I also long for the bright display o£ colors — first in the fall trees, and then in the limits around homes and at Rockefeller Center. Floridians decorate too, but can't create the special feel of a New England winter.

    I suppose the biggest reason why I return is to celebrate the holidays with people I haven't seen in months. What could be better than sitting with family and friends for a Thanksgiving turkey dinner, or watching neighbors' children excitedly open gifts on Christmas? Even the first snowfall seems special. I especially enjoy seeing a bright red bird settling on a snow-covered branch (My wife and I spend winters at a retirement community in Ridge, and I'm grateful that I don't have to shovel.）

    While these simple pleasures are not unique to Long Island, they are some of the reasons why I come back. Who says you can't go home?