Neuroscientists have explained the risky, aggressive or just plain baffling behavior of teenagers as the product of a brain that is somehow compromised. Groundbreaking research in the past 10 years, however, shows that this view is wrong. The teen brain is not defective. It is not a half-baked adult brain, either. It has been forged by evolution to function differently from that of a child or an adult.

    The most important of the teen brain's features is its ability to change in response to the environment by modifying the communication networks that connect brain regions. It allows teenagers to make enormous progress in thinking and socialization. But the change also makes them sensitive to dangerous behavior and serious mental disorders.

    The most recent studies indicate that the riskiest behaviors arise from a mismatch between the maturation of networks in the limbic system(边缘系统), which drives emotions at adolescence, and the maturation of networks in the prefrontal cortex（前额皮质）, which occurs later and promotes sound judgment and the control of impulses. Indeed, we now know that one's prefrontal cortex continues to change noticeably until his 20s. And yet adolescence seems to be starting earlier, extending the “mismatch years.”

    The plasticity of networks linking brain regions—and not the growth of those regions, as previously thought—is key to eventually behaving like an adult. Understanding that, and knowing that a widening gap between the development of emotional and judgment networks is happening in young people today, can help parents, teachers, counselors and teenagers themselves. People will better see that behavior such as risk-taking and turning away from parents and toward peers are not signs of cognitive or emotional problems. They are a natural result of brain development, a normal part of adolescents learning how to negotiate with a complex world.

    The same understanding can also help adults decide when to intervene. A 15-year-old girl's departure from her parents' tastes in clothing, music or politics may be a source of anxiety for Mom and Dad but does not indicate mental illness. A 16-year-old boy's tendency to skateboard without a helmet or to accept risky dares from friends is not unimportant but is more likely a sign of short-range thinking and peer pressure than a desire to hurt himself. Knowing more about the unique teen brain will help all of us learn how to separate unusual behavior that is age-appropriate from that which might indicate illness. Such awareness could help society reduce the rates of teen addiction, motor vehicle accidents and depression.

    A new research has discovered that meditation(冥想)and oxygen sport together reduce depression. The Rutgers University study found that this mind and body combination, done twice a week for only two months, reduced the symptoms of a group of students by 40 percent.

    “We are excited by the findings because we saw such a meaningful improvement in both clinically depressed and non-depressed students,” said lead author Dr. Brandon Alderman. “It is the first time that both of these two behavioral ways have been looked at together for dealing with depression.”

    Researchers believe the two activities have an interactive effect in combating depression. Alderman and Dr. Tracey Shors discovered that a combination of mental and physical training(MAP) enabled students with major depressive disorder not to let problems or negative thoughts defeat them.

    Rutgers researchers say those who participated in the study began with 30 minutes of focused attention meditation followed by 30 minutes of oxygen sport. They were told that if their thoughts drifted to the past or the future they should refocus on their breathing, which enabled those with depression to accept moment-to-moment changes in attention.

    Shors, who studies the production of new brain cells in the hippocampus—part of the brain involved in memory and learning—says scientists have shown in animal models that oxygen sport exercise keeps a large number of certain cells alive.

    The idea for the human intervention(干预)came from her laboratory studies, she says, with the main goal of helping individuals acquire new skills so that they can learn to recover from stressful life events.

    By learning to focus their attention and exercise, people who are fighting depression can acquire new learning skills that can help them process information and reduce the overwhelming recollection of memories from the past, Shors says.

    “We know these treatments can be practiced over a lifetime and that they will be affective in improving mental health,” said Alderman. “The good news is that this intervention can be practiced by anyone at any time and at no cost.”

    A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度)of yellow makes it easier for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.

    The study was led by Prof Ho. To test whether there was a causal relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6.1 fewer accidents per 1,000 taxis per month.

    The researchers also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio(比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76.6 fewer accidents would occur per month or 917 fewer accidents per year. Assuming an average repair cost of $1,000 per car and a downtime of six days, switching the color of all taxis to yellow could produce an annual savings of $2 million.

    "We are eager to continue to validate(证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For instance, we hope to compare the accident rates of yellow school buses against other colors to find out if yellow is indeed a safer color for school buses. Besides, we are also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors," explained Prof Ho.

    According to the Guinness World Records, a Sitka Spruce (锡特卡云杉) growing on New Zealand's southernmost island is the loneliest tree on Earth. Not only is it the only tree on Campbell Island, but the nearest other tree can be found over 200 km away on the Auckland Islands.

    Bluff, Campbell Island is one of the harshest places in the world. With strong winds blowing almost all year round and less than 600 hours of sunshine, it's not exactly a good place to live in, which is probably why, except for occasional visits by research scientists, it, has remained deserted for over half a century.

    It is believed that the Sitka Spruce on Campbell Island was planted by Lord Ranfurly, a former governor of New Zealand, sometime between 1901 and 1907. It's not clear why he decided to plant there, but according to some sources he said that the island was not productive, and took the first step to cover it with forestry. His idea was never going to work because of the harsh climate of the area, but somehow the Sitka Spruce survived.

    Apart from its reputation as the loneliest tree on Earth, the Sitka Spruce of Campbell Island has a series of other particularities. First of all its shape makes it look more like a giant cauliflower than a tree. This is believed to have been caused by repeatedly cutting down its trunk every year, for decades. Another interesting thing about the world's loneliest tree is that, though it is over 100 years old, it has never produced cones (球果).

    Who knew a lonely tree growing 200 km away from its nearest cousins could be so interesting?

    Of all the things that will make life entirely happy, the greatest is the possession of friendship. One loyal friend is worth ten thousand relatives. Friends are very rare jewels, indeed. They make you smile and encourage you to succeed.

    On the first Sunday in August, it's time to recognize your friends and their contribution to your life. The first Sunday in August was fixed as National Friendship Day by the U.S. Congress in 1935, and remains a tradition observed in many countries and cultures. In 1997, the United Nations named Winnie the Pooh as the world's Ambassador of Friendship.

    Apparently, there are several friendship holidays, all of which fall on fixed dates.

    National Friendship Day is on the first Sunday in August

    Women's Friendship Day is on the third Sunday in September

    International Friendship Month is February

    Old Friends, New Friends Week is the third week of May

    People show their appreciation for friendship in various ways. Some expressions may be practical ones, such as flowers, particularly the pink friendship roses, cookies, chocolates, souvenirs from their vacations, a tape of favorite songs, farewell dinners, and welcome balloons.

    Recipe for Friendship  2 cups of patience, 1 heart full of love, 2 handfuls of generosity, 2 cups of loyalty, 1 cup of understanding, A dash of laughter. Mix them all well. Spray generously over a lifetime and serve everyone you meet.

    Friendship helps to bring peace and positivity to the globe, another great reason to celebrate! Although our friends certainly deserve thanks on more than just one day of the year, what better day to honor them than Friendship Day!

    Unemployment in the United States is still high at 6.7％. But for job seekers, especially those with college educations, researchers say finding a job can be as easy as logging(登录)on to a computer. It used to be that looking for a job meant hurrying around, knocking on doors and turning to ads. But that's changing, thanks to the Internet. A new report says, for college graduates, looking for a job is getting easier. More than 80 percent of the jobs are available online.

    At the height of the depression(萧条), in the U. S. the highest unemployment rate was 10％, just a little more than two million jobs were being posted each month. But as the recovery takes hold, the job picture looks increasingly bright.

    That's great news for Hamilton. Only once has he ever applied in person for a job at a shopping mall. He said, "I think my generation—the idea of going door to door, out knocking and saying, hey are you hiring? —like that—doesn't exist anymore…those days are gone. Just go online.''

Kim Dancy recently graduated with a master's degree in Public Policy. She found her dream job as an education policy researcher. But she says finding the perfect job online takes a lot of perseverance. She said, "It can be really frustrating and it takes a long time, but if you applied for enough positions and really do your homework you will get somewhere.

    The report's findings suggest careers in Science, Technology, Engineering and Math provide the greatest opportunities, with salaries that range between $30 to $45 an hour. But for maximum income and satisfaction, workers must be prepared to move and change jobs at least every five years.