This Monday, the nation will start to celebrate Presidents' Day, just seven days before George Washington's birthday. Everyone agrees that day is a holiday. but is it just to celebrate George Washington's Birthday? What about Abraham Lincoln? Some government offices call it Presidents' Day. Others say the holiday is officially Washington's Birthday. Confused yet?

    George Washington was elected the country's first President on April 30,1789. Soon after, Americans began publicly celebrating his birthday. Presidential historians say the actual date of George Washington's birth is February 11,1732. But a change inthe calendar system 20 years later shifted all dates, making Washington's birthday February 22, which is now well accepted. In 1879. Congress made Washington's birthday an official federal holiday. It was the first federal holiday to celebrate an individual's birthday. In 1968, Congress passed the Monday Holidays Act, which moved the holiday to the third Monday in February. The new law did not change the holiday's name. It was still called Washington's Birthday, even though some law makers wanted to call it Presidents' Day to include Abraham Lincoln, whose actual birthday is February 12.

    Many people argue that the holiday should celebrate all past Presidents. They feel Lincoln should be honored for his role in preserving the nation during the Civil War and helping to free slaves. Others feelthe holiday should only honor Washington. the country's first President. They say shifting the focus away from Washington would mean future generations of kids would not know about the Father of Our Country.

    Laws have been introduced in Congress over the years to requireuse of the term “George Washington's Birthday.”but none of those laws have been passed. Meanwhile, many stategovernments and school districts now use the term “Presidents' Day．”Many stoles also use it to promote holiday sales.

    Should the holiday honor Washington, Washington and Lincoln, or all past Presidents? Write to emailbag@timeforkids, com and tell us what you think.

    The behaviour of a building's users may be at least as important as its design when it comes to energy use, according to new research from the UK Energy Research Centre (UKERC). The UK promises to reduce its carbon emissions (排放）by 80 percent by 2050, part of which will be achieved by all new homes being zero-carbon by 2016. But this report shows that sustainable building design on its own — though extremely important- is not enough to achieve such reductions: the behaviour of the people using the building has to change too.

    The study suggests that the ways that people use and live in their homes have been largely ignored by existing efforts to improve energy efficiency (效率)，whichinstead focus on architectural and technological developments.

     ‘Technology is going to assist but it is not going to do everything,'explains Katy Janda, a UKERC senior researcher，‘consumption patterns of building users can defeat the most careful design. 'In other words，old habits die hard, even in the best-designed eco-home.

    Another part of the problem is information. Households and bill-payers don't have the knowledge they need to change their energy-use habits. Without specific information，it's hard to estimate the costs and benefits of making different choices. Feedback (反馈） facilities, like smart meters and energy monitors，could help bridge this information gap by helping people see how changing their behaviour directly affects their energy use; some studies have shown that households can achieve up to 15 percent energy savings using smart meters.

    Social science research has added a further dimension (方面），suggesting that individuals'behaviour in the home can be personal and cannot be predicted 一 whether people throw open their windows rather than turn down the thermostat (恒温器) , for example. Janda argues that education is the key. She calls for a focused programme to teach people about buildings and their own behaviour in them.

    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.

    Not long ago, I tried convincing my three daughters that the world's secrets are hidden inside silence. The girls looked at me skeptically. Surely silence is nothing?

    Sitting there at the dinner table, I suddenly remembered their curiosity as children, their wondering about what might be hiding behind a door and their amazement as they stared at a light switch and asked me to “open the light”. But now they are 13, 16 and 19 and wonder less and less. If they still wonder at anything, they quickly pull out their smart phones to find the answer. None of them have any interest in discussing with me. To attract their attention, I told them about two friends of mine who had decided to climb Mount Qomolangma.

    Early one morning they left base camp to climb the south-west wall of the mountain. It was going well. Both reached the summit, but then came the storm. They soon realized they would not make it down alive. The first got hold of his pregnant wife by satellite phone. Together they decided on the name of the child that she was carrying. Then he quietly passed away just below the summit. My other friend was not able to contact anyone before he died. No one knows exactly what happened on the mountain in those hours. Thanks to the dry, cool climate 8km above sea level, they have both been freeze-dried. They lie there in silence, looking no different.

    The girls remained quiet, listening. It seemed as though they had got something.

    It is easy to assume that the essence (本质) of technology is technology itself, but that is wrong. The essence is the time we spend with our family and how much freedom we have by technology.

    The burst of barking suddenly woke me up. It was 2:30 a.m. in the early morning. Wondering why Rock was making so loud noises, I decided to go to him. By the time I made it to the bottom of the stairs, he was running up. I felt strange, for he had never come up the stairs, no matter what. I think that was his way of telling me, “We've got to go back up.”

    When I got to the top of the stairs, I turned around and saw a light on, but I didn't remember leaving one on. I walked downstairs again, and that's when I saw fire. I immediately shouted to my wife to wake up and get our three kids. I grabbed a knife and cut out the plastic that covered the window to the porch roof. I then forced open the window and kicked out the screen. I got everybody out on the roof and threw a blanket out there so we wouldn't slip off. It was cold, January cold. Then I started screaming for help. But help never came.

    I was scared of heights, but I couldn't let my family burn up. So I just jumped off the roof and got the wind knocked out of me when I landed.

    I found our ladder, placed it against the house, and climbed back up to the roof. I wrapped my arms around my daughter and carried my nine-month-old with my teeth, by his little sleeper. Then I climbed down the ladder. Once on the ground, I had my little girl hold her brother, and I went back up to the roof to get my other daughter. Then I went back up again and got my wife. I tried to get my dog, but he just disappeared in the black smoke. I never saw Rock alive again.