After ruling the tennis world for almost five years,Roger Federer is adjusting to life at NO.2.But,like any king whose throne has been taken away,the Swiss star is already planning secretly bis return to power,beginning at this week's US Open.

    The problem is, many experts think he will never do it.They blame everything from age and tough competition to his racket and psychology.

    For years Federer, had enjoyed the view from the top.Competitors saw him as undefeated,and for the most part he was.However,before the 2008 season began,Federer had an illness that stole his strength and clearly affected his play on the court.Ever since,he has struggled to return to form,winning just two of his last 14 tournaments.

    "Twenty-seven is an age when your body starts talking back to you."tennis great John McEnroe told the New York Times.

    Pancho Sefura, another tennis great, noted that Federer is also facing a maturing crop of young talents."There are too many great players now,"he said,naming Britain's Andy  Murray,21,and Latvia's Ernests Gulbis,20.

    US magazine Sports Illustrated tennis columnist Jon Wertheim suggested that part of Federer's problem could be his insistence on using a small racket.He says that the smaller head demands ball control.But we see time and again that racket makers try to get players to use a certain stick-one they would like to market to consumers and it has a negative effect on the professional game.

    Sports psychologist Jim Loehr told the Times that Federer is probably feeling "a sense of doubt"after being considered as undefeated for so long.If Federer is to recover his state of being undefeated,Loehr said he must overcome his doubt."Federer doesn't need fame and money.But he has to get better.He has to go t.o a whole new level.That's the only way he stays in the game," he said.

    As for beginning his first Grand Slam in ages as the NO.2 seed, Federer said it might be for the best."Five years almost,I was expected to win every tournament I entered,"he said,"so maybe Rafael Nadal now feels what I had to feel for a very long time.It will be interesting to see how he handles it."

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    You carry a 1.3 kg mass of fatty material in your head that controls everything you will ever do. This fantastic control center lets you think, learn, create, and feel emotions. It also controls everything your body does. What is this amazing machine? It's your brain — a structure so amazing that the famous scientist James Watson called it ＂the most complex thing we have yet discovered in our universe＂.

    Imagine your kitten jumped onto the kitchen counter, and was about to step onto a hot stove. You would have only seconds to act. In situations like this, your brain reads the signals from your eyes and quickly calculates when, where and at what speed you need to run to save her. Then it tells your muscles to move. No computer can match your brain's great ability to download, process, and react to the flood of information from your eyes, ears and other sensory organs.

    If a bee lands on your foot, sensory neurons(神经元) in your skin send this information to your brain at a speed of more than 240 kilometers per hour. Your brain then uses motor neurons to send a message back to your foot: Shake the bee off quickly! Motor neurons can send this information at more than 320 kilometers per hour!

    Your brain contains about 100 billion tiny cells: neurons — it would take you more than 3,000 years if you tried to count them all. Whenever you dream, laugh, think, see or move, tiny chemical and electrical signals are racing between these neurons along billions of tiny neuron pathways. Believe it or not, the activity in your brain never stops. Countless messages fly around inside it every second, like a super-fast game of table tennis. Your neurons create and send more messages than all the phones in the entire world. And although a single neuron generates only a tiny amount of electricity, all your neurons together can generate enough electricity to power a light bulb.

    Anew international study shows that some peopled biological clock plays a powerful role for their life expectancy, regardless of lifestyle choices.

Published in the latest issue of Aging on Wednesday, the study has found the most definitive evidence to explain why some people keep healthy lifestyle but die younger than others.

    Geneticist Steve Horvath from the University of California, Los Angeles (UCLA), led a team of 65 scientists around the world to record age-related changes to human DNA, analyse blood samples collected from 13,000 people and estimate their lifespan.

    A higher biological age, regardless of actual age, consistently predicts an earlier death, the study says.

    “You get people who are vegan, sleep 10 hours a day, have a low-stress job, and still end up dying young,” Horvath said in a statement. “We have shown some people have a faster innate aging rate.”

    The findings discovered that 5 percent of the population ages at a faster biological rate, which translated to a roughly 50 percent higher than average risk of death at any age.

    “The great hope is that we find anti-aging interventions that would slow your innate aging rate,” Horvath said, adding that “this is an important milestone to realizing this dream.

Volunteer Opportunities

    Ring the bells

    The Salvation Army needs bell ringers for its annual Red Kettle Christmas Campaign. Two hour shifts begin on Nov.12 and run Mondays through Saturdays. Volunteers can contact Jim Evers at jimevers@usc.salvationarmy.org or at 764-0962, or sign up online at ringbels.org.

    Read to children

    Join the United Way and Child Care Aware in supporting the development and learning of young children. Volunteers are needed to spend 30 minutes a week reading to children and guiding related activities using literacy kits（识字工具包）provided by Childcare Aware of Eastern Kansas .A two-hour literacy training will be provided. To ensure continuity for the children in the program, we are asking that volunteers make a six-month commitment. Please contact Shelly at 865-5030, ext.301 or at volunteer@unitedwaydgco.org.

    Garden with a neighbor

    Douglas Country Housing Inc. is looking for volunteers to assist a senior man in need of help with an overgrown garden before winter arrives. One to two hours of your time will make a huge difference in someone's quality of life. No previous gardening experience is required. Please e-mail rsovista@ldcha.org or call 842-1533.

    Feed your friends

    Just food fights hunger in our community. Help Just Food kick off the holiday season by packing. Thanksgiving meal boxes for families in need. Every year Just Food provides Thanksgiving meals to families in Douglas Country that will otherwise go without. Your help is needed for distributing these meals in advance of Thanksgiving. Help is needed on the following days and times:

    9 a. m. –7 p. m. Monday, Nov. 21.

    9 a. m. –7 p. m. Tuesday, Nov. 22.

    The maximum number of volunteers is 15 at a time. To sign up, click here.

    Learning is so complex that there are many different psychological theories to explain how people learn. A psychologist named Albert Bandura suggested a social learning theory which shows that observation, imitation (模仿), and modeling play a primary role in this process.

    In Albert Bandura's opinion, people can learn through observation. Observational learning doesn't even necessarily require watching another person join in an activity. We can also learn by reading, hearing, or watching the actions of characters in books and films. However, just observing someone else's actions isn't always enough to lead to learning. Your own mental state also plays an important role in determining whether a behavior is learned or not. In addition, though in many cases, learning can be seen immediately when the new behavior is displayed, yet sometimes we can learn things even though that learning might not be immediately obvious, which means people can learn new information without showing new behaviors.

    Not all observed behaviors are effectively learned. Certain requirements need to be related to the observational learning process. For example, you need to be paying attention. Also your retention is an important part of observational learning as you need to pull up information later and act on it during the process. Once you've paid attention to the model and kept the information, it's time to actually perform the behavior you observed. Further practice of the learned behavior leads to improvement. Finally, you have to be motivated to imitate the behavior that has been modeled.

    Social learning theory have many real-world applications. For example, researchers employ it to look into and understand ways that positive role models can be used to encourage desirable behaviors. Besides, it's also applied in the field of education, and today, both teachers and parents recognize how important it is to model appropriate behaviors.

Earth's next superpower

The following countries have been sitting on hidden talents. And now they're about to fly.

NIGERIA (尼日利亚)

Nigeria says it pumps out as much oil as the other two oil-producing countries, Kuwait and Iraq. All this oil is cycling cash into the Nigerian economy and creating extremely rich businessmen. Analysts say that if Nigeria can improve its schools and technology, it could balloon into the world's 13th largest economy by 2050, right between Turkey and Italy. If that reason is not enough for optimism, Nigeria's president also has the sunniest name of any world leader: Goodluck Jonathan.

VIETNAM

As agriculture has given way to industry, unemployment in Vietnam has dropped. What's Vietnam's trick? It's ready to work. Other countries' laborers aren't as cheap as they used to be, which makes Vietnam a relative bargain for companies that need new factories abroad. However, the country has almost no railroads, its highways are in poor condition, and its largest city has just one airport, which was built before the Vietnam War. So what's the use of producing export-ready goods if there's no convenient way to ship them? The good thing is that, however, officials are widening highways, building a new airport and so on.

CHILE (智利)

Pipes, computers, motors, and your microwave all have one thing in common: They're made with copper (铜). Copper makes the world go round. And luckily for Chile, it's got about a third of the planet's copper supply. It just needs a way to dig it up and the government is pouring money into the country's mines.