At one time, computers were expected largely to remove the need for paper copies of documents(文件) because they could be stored electronically. But for all the texts that are written, stored and sent electronically, a lot of them are still ending up on paper.

    It is difficult to measure the quantity of paper used as a result of use of Internet-connected computers, although just about anyone who works in an office can tell you that when e-mail is introduced, the printers start working overtime. “I feel in my bones this revolution is causing more trees to be cut down ,” says Ted Smith of the Earth Village Organization.

    Perhaps the best sign of how computer and Internet use pushes up demand for paper comes from the high-tech industry itself, which sees printing as one of its most promising new markets. Several Internet companies have been set up to help small businesses print quality documents from a computer. Earlier this week Hewlett-Packard Co. announced a plan to develop new technologies that will enable people to print even more so they can get a hard copy of a business document, a medical record or just a one-line e-mail, even if they are nowhere near a computer. As the company sees it, the more use of the Internet the greater demand for printers.

    Does all this mean environmental concerns have been forgotten? Some activists suggest people have been led to believe that a lot of dangers to the environment have gone away.

    “I guess people believe that the problem is taken care of, because of recycling,” said Kelly Quirke, director of the Rainforest Action Network in San Francisco. Yet Quirke is hopeful that high-tech may also prove helpful. He says printers that print on both sides are growing in popularity.

    The action group has also found acceptable paper made from materials other than wood, such as agricultural waste.

    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.

    Music for Humans and Humpback Whales (座头鲸)

    As researchers conclude in Science, the love of music is not only a universal feature of the human species but is also deeply fixed in complex structures of the human brain and is far more ancient than previously suspected.

    In the articles, researchers present various evidence to show that music-making is at once an original human “business”, and an art form with skillful performers throughout the animal kingdom.

    The new reports stress that humans hold no copyright on sound wisdom, and that a number of nonhuman animals produce what can rightly be called music, rather than random sound. Recent in-depth analyses of the songs sung by humpback whales show that, even when their organ would allow them to do otherwise, the animals converge on the same choices related to sounds and beauty, and accept the same laws of song composition as those preferred by human musicians, and human ears, everywhere.

    For example, male humpback whales, who spend six months of each year doing little else but singing, use rhythms (节奏) similar to those found in human music and musical phrases of similar length—a few seconds. Whales are able to make sounds over a range of at least seven octaves (八度音阶), yet they tend to move on through a song in beautiful musical intervals (间隔), rather than moving forwards madly. They mix the sounds like drums and pure tones in a ratio (比例) which agrees with that heard in much western music. They also use a favorite technique of human singers, the so-called A-B-A form, in which a theme is stated, then developed, and then returned to in slightly revised form.

Perhaps most impressive, humpback songs contain tunes that rhyme. “This suggests that whales use rhyme, the same way we do: as a technique in poem to help them remember complex materials,” the researchers write.

    As a young girl growing up in the 1930s, I always wanted to fly a plane, but back then it was almost unheard of for a woman to do that. I got a taste of that dream in 2001, when my husband arranged for me to ride in a hot air balloon for my birthday. But the experience turned out to be very dull. Around that time, I told my husband that I wanted to skydive. So when our retirement community announced that they were having an essay competition and the topic was an experience of a lifetime that you wanted to have, I decided to write about my dream.

    In the essay, I wrote about my desire to skydive, stating George Brush Sr. did age 80. Why not me? I was just 84 and in pretty good health. A year went by and I heard nothing. But then at a community party in late April 2009, they announced that l was one of the winners. I just couldn't believe it. Inspired by this, I decided to realize my dream, even though some of my family members and my doctor were against it.

    One June 11, 2009, nearly 40 of my family and friends gathered in the area close to where I would land while I headed up in the airplane. My instructor, Jay, guided me through the experience. The plane was the noisiest one I had ever been in, but I wasn't frightened－I was really just looking forward to the experience. When we reached 13,000 feet, Jay instructed me to throw myself out of the plane. When we first hit the air, the wind was so strong that I could hardly breathe. For a second I thought, “What have I gotten myself into?” But then everything got calmer. We were in a free fall for about a minute before Jay opened the parachute （降落伞）, then we just floated downward for about five minutes. Being up in the clouds and looking at the view below was unlike anything I have ever felt－much better than the hot air balloon. I was just enjoying it.

    Skydiving was really one of the greatest experiences of my life. I hope other people will look at me and realize that you don't stop living just because you are 84 years old. If there's something you want to experience, look into it. If it's something that is possible, make it happen.

    There is an English saying that “Laughter is the best medicine.” Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it has on the human body. They have found that laughter can really improve people's health.

    Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their hearts, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, makes the heart beat quicker and makes people breathe deeper; it also works on several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial(有益的).

Other tests have shown that laughter appears to be able to reduce the effects of pain on the body. In one experiment doctors produced pain in groups of students who listened to different radio programs. The group that tolerated（忍耐）the pain for the longest time was the group which listened to a funny program. The reason why laughter can reduce pain seems to be that it helps to produce a kind of chemical in the brain which diminishes both stress and pain.

    As a result of these discoveries, some doctors in the United States now hold laughter clinics(诊所), in which they help to improve their patients' condition by encouraging them to laugh. They have found that even if their patients do not really feel like laughing, making them smile is enough to produce beneficial effects similar to those caused by laughter.

    Construction on Knolly's Tunnel began in 1896, and it was opened on August 13th, 1898 by the man it was named after--Sir Clement C. Knolly, Acting Governor of Trinidad. It linked Rio Claro with Port of Spain. Its architecture is still admired and studied today, and many are amazed that Knolly's Tunnel has stood up to the earth's movement over so many years.

    Much research is being done on the tunnel. At the top of Knolly's Tunnel are cottages covered with leaves, where visitors can sit and enjoy the beauty of nature. Standing at the beginning of Knolly's Tunnel, you can see nothing but the tiny light at the end. The train tracks have been removed and replaced with small stones. Visitors can drive through the tunnel or walk through, but should do so in groups for safety. In the old days, there were no lights, but now there are street lights on the way to the tunnel, though not inside.

    On your way in, you may notice some manholes on the walls of the tunnel. These were there for individuals to step into for safety as the train passed. Knolly's Tunnel can be accessed through Tabaquite and through Mitchell Gap. The road was recently improved, but is better when you enter from Tabaquite, and there are signs on the road directing you to Knolly's Tunnel.

    On the drive to Knolly's Tunnel there are two other cottages where visitors can sit and just enjoy nature. At the site itself, there is nothing to purchase to eat or drink, but in Tabaquite there are several bars, a restaurant, and food outlets. A gas station and a health centre are also close by.

    For those who admire architecture, Knolly's Tunnel is a must-see when visiting Trinidad. For the nature lovers, there is no better place for them to be and for the historians, they can walk or drive through Knolly's Tunnel knowing that many of our ancestors toiled (worked hard) on its structure. So when you visit Trinidad, don't forget to take a look at Knolly's Tunnel!