【推荐1】Working out on an empty stomach could increase the health benefits of the activity, according to a well-timed new study of the interaction of meal timing, physical health and exercise.

The study, which involved people sitting for long and moderate cycling, suggests that whether and when we eat may affect how exercise affects us. In general, any exercise improves our health. But a wealth of recent science and personal experience indicate that different people can respond to similar exercise routines in different ways. Even if everyone completes the same amount of exercise, some people become more fit than others, or lose more weight, or gain greater control of their blood sugar.

Most exercise scientists believe that our genes, diets, figures, characters and other subtle aspects of our lives act together to shape how our bodies react to exercise. But some researchers suspect that meal timing matters as well. Working muscles need fuel during exercise, mostly in the form of sugar or fat. That fuel can come from our most recent meal, once its constitution sugars and fats reach our bloodstreams, or from our bodies’ stores of fats and sugars.

We all have such stores, especially of fat, some of it staying in our muscles and they are well and evenly matched. This muscle fat becomes problematic if we accumulate too much of it. Fatty muscles do not respond well to the hormone insulin (胰岛素), which directs sugar from the blood into the muscles. As a result, excess fat can contribute to insulin resistance, high blood sugar levels and increased risks for Type 2 diabetes and other metabolic (新陈代谢的) conditions.

【推荐3】Air pollution may be causing baldness, scientists have shown for the first time. A new study found that fine particulate matter emitted by cars would damage the skin that holds hair follicles(毛囊) in place. A series of laboratory tests on human cells showed that levels of the crucial proteins needed for hair to grow and be retained decreased when they were exposed to pollution particles. While there is a growing body of evidence showing how these tiny particles can damage internal health, including by entering the bloodstream through the lungs, this is the first to demonstrate such a risk to the surface of the body.

The study was conducted by exposing cells from the human follicle dermal papilla cells (HFDPCs) to various concentrations of PM10-like dust and diesel particles. After 24 hours the researchers performed a process, known as western blotting, to detect the levels of specific proteins in the cells.

The results showed that the presence of PM10 and diesel particles decreased levels of B-catenin, the protein responsible for hair growth. The study also revealed that the levels of three other proteins---cyclin D1, cyclin E and CDK2, which are responsible for hair growth and hair retention, were decreased by PM10-like dust and diesel particles in a “dose-dependent” manner.

Dr Hyuk Chul Kwon, who led the study at the Future Science Research Centre, said, “While the link between air pollution and serious diseases such as cancer and lung diseases is well established, there is little-to-no research on the effect of particulate matter exposure on the human skin and hair in particular. Our research explains the mode of action of air pollutants on HFDPCs, showing how the most common air pollutants lead to hair loss.”

Sources of PM include the burning of fossil fuels---petrol and diesel, as well as other solid fuels, and other industrial activities such as building, mining and the manufacturing of building materials like bricks.

“While it is difficult to escape from the surrounding pollution, limiting the time for walking in busy streets, especially during rush hours, should help reduce exposure,” said Dr Kwon. “If you are exercising outdoors, try to do so in areas that are less polluted and do not spend too much time waiting at traffic hot spots such as traffic lights.”

【推荐3】How clever can a computer be? Maybe you can get the answer after reading the following passage about a newly-developed US computer program called SmarterChild.

If you ran into Smarter Child online, you would be surprised at this kid’s huge memory. It can remember many facts. For example, Smarter Child knows everybaseball player in every team this season and the weather in every city across the US.He also knows every word in the dictionary. However, if you ask Smarter Child other private questions, you will get strange answers. A question about Smarter Child’s age returns, “I’ll be older than you after further study!”, and asking where he lives, you will get, “In a clean room in a high-tech building in California.”

Smarter Child uses the huge information on the World Wide Web as his memory bank. To answer questions about spelling, for example, Smarter Child goes towww.ahdictionary.com. For the weather, he visits www.intellicast.com. He turns to www.the-scientist.com for scientists and www.moviefone.com for a fantastic movie.

Some scientists believe that by joining many systems of the Internet, an Artificial Intelligence (AI) with the combined (结合的) knowledge of, say,   Albert Einstein, Richard Nixon and Britney Spears could be born. However, Smarter Child has difficulty in discerning whether a behavior is right or wrong, which is obvious to any young child. If he wants to think and learn without any help from the programmers like boy-computer David in the movie Artificial Intelligence (AI), he must solve two problems.

The first is that computers find it difficult to read web pages because the files aresorted in different ways. That’s why programmers need to tell Smarter Child where tolook for the weather. It would be a much more difficult task to let him find it byhimself. Another problem is that while Smarter Child can deal with information moreexactly and faster than any human, he needs programmers to make better systems thatallow machines to solve problems of common sense, which is a huge challenge.