[原创]借块宝地练听力(每天一更新)

cvvt1986

Mosquitoes carry nasty diseases—dengue fever, west nile, malaria. But the microbes that cause those diseases don’t attach themselves to the mosquitoes and then immediately latch onto their next victim. They need time to grow and replicate in the mosquito before migrating to the bug’s salivary glands. For example, the dengue fever virus takes about two weeks to incubate.

So researchers from the University of Queensland in Australia and Central China Normal University are looking at a way to shorten the lives of mosquitoes—and thus curtail their disease-transmitting ability.

Researchers worked with a bacterial parasite called Wolbachia that infects numerous insect species. They spent three years adapting it to infect the Aedes aegypti mosquito, which carries dengue fever. It cut the lives of the mosquitoes by more than half. Those results were reported in the January 2nd issue of the journal Science. The scientists say that because Wolbachia shortens a mosquito’s life, the insects are that much less likely to pass on the diseases they carry. So a relatively inexpensive and effective human disease prevention program could be to mass-infect mosquitoes with Wolbachia. Which should make the medical community buzz.

—Cynthia Graber 

cvvt1986

Men's Chess Superiority Explained
 

http://podcast.sciam.com/daily/sa_d_podcast_081229.mp3

[此贴子已经被作者于2009-1-4 9:46:06编辑过]

cvvt1986

Women are so much better than men at so many things. But according to a report published by the Royal Society, chess is not one of them. The topic of sex differences when it comes to matters of the mind is, needless to say, a divisive one. Those who wish to argue that women are just not as smart as men often point to chess as their proof. Although girls can obviously play, no woman’s ever been world champion. But before looking for cultural or biological explanations for the disparity, scientists say you need to do the math.

Serious chess players are assigned ratings based on their performance against other players. So the scientists compared the ratings of the top hundred male and top hundred female players from Germany. And they found that the men indeed outperformed the women. However that difference can be almost entirely explained by statistics. Because the larger the population, the wider the range of measured scores—the bell curve has a longer tail. And because many more men play than women, the best male players are extreme outliers on that bell curve. As more women play, a few should also reach those extremes, right out there with the men. To which one might be tempted to say: Checkmate.

—Karen Hopkin 

cathyiris

好贴~

cvvt1986

Great Expectations for 2009

http://podcast.sciam.com/psych/sa_p_podcast_081230.mp3

[此贴子已经被作者于2009-1-4 9:49:58编辑过]

cvvt1986

Making decisions for 2009? 

Well maybe consider Duke professor Dan Ariely’s book, Predictably Irrational in which he describes how our expectations can hugely affect our decisions.

At M.I.T., he and two colleagues had several hundred students try two different pints of beer. One was Budweiser and the other was Budweiser, but with balsamic vinegar added. 

Students who weren’t told about the “secret ingredient,” vastly preferred the balsamic beer. But those who were informed before tasting the beer, hated it.

If people think up front that something might be distasteful, Ariely argues, the odds are high that they’ll experience it negatively, no matter how intrinsically good it is.

But can expectations change the physiology of our experience?

In a second experiment participants were told about the vinegar after they tasted the beer. If knowledge of the vinegar is merely information, then our perception should be the same regardless of when we get that information.

But this group loved the beer just as much as those who never heard about the vinegar.

So our expectations can reshape our sensory perceptions. Then, should you have zero expectations for the future? Not necessarily. Maybe just expect great things in 2009.  After 2008, it can’t hurt, right?

—Christie Nicholson

Growingwqy

好!

Growingwqy

好慢啊  几乎听不了, 缓冲缓冲...

stephanie922

我也在听这个 不过刚开始都听不懂 努力~``

cvvt1986

以下是引用stephanie922在2009-1-4 22:30:00的发言：
我也在听这个 不过刚开始都听不懂 努力~``

先多看会文章,然后再听