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This is Scientific American's 60-Second Science. I'm Christopher Intagliata. Got a minute?

Asbestos increases the risk for certain cancers. The fibers¹ are thought to do so by skewering² cells, setting off chemical reactions that lead to inflammation, DNA³ damage and cell death. Some studies have suggested carbon nanotubes might have similar effects—because they're long and spiky⁴, like asbestos. But why would a cell draw in a nanotube, essentially⁵ impaling⁶ itself on a microscopic⁷ lance?

To find out, researchers exposed mouse and human cells to carbon nanotubes. They saw that the cells frequently engulfed⁸ the tubes—almost always tip-first. They then simulated that sword-swallowing maneuver⁹ on a computer. And they concluded that the round tips of nanotubes feel like bite-sized spheres, which cells commonly ingest. But once the cell senses the nanotube isn't bite-size? It's too late. It can't stop sucking it in. The finding is in the journal Nature Nanotechnology.

As nanotubes may have medical applications, making them safe is key. And there may be a way to keep cells from biting off more than they can swallow—snip off the nanotubes' rounded tips. In one such simulation, the cells left the tubes alone—meaning we may get to have our nanotubes, without eating them, too.

Thanks for the minute. For Scientific American's 60-Second Science, I'm Christopher Intagliata.

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收听单词发音

1 fibers
光纤( fiber的名词复数 )；（织物的）质地；纤维，纤维物质
参考例句：
Thesolution of collagen-PVA was wet spined with the sodium sulfate as coagulant and collagen-PVA composite fibers were prepared. 在此基础上，以硫酸钠为凝固剂，对胶原-PVA共混溶液进行湿法纺丝，制备了胶原-PVA复合纤维。 Sympathetic fibers are distributed to all regions of the heart. 交感神经纤维分布于心脏的所有部分。

2 skewering
v.（用串肉扦或类似物）串起，刺穿( skewer的现在分词 )
参考例句：
But Mr Stone is more interested in skewering rapacious financiers than rash homeowners. 但是斯通先生更感兴趣的是去讥讽贪婪的金融家，而不是冲动的物业购买者。来自互联网

3 DNA
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句：
DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。 Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

4 spiky
adj.长而尖的，大钉似的
参考例句：
Your hairbrush is too spiky for me.你的发刷，我觉得太尖了。 The spiky handwriting on the airmail envelope from London was obviously hers.发自伦敦的航空信封上的尖长字迹分明是她的。

5 essentially
adv.本质上，实质上，基本上
参考例句：
Really great men are essentially modest.真正的伟人大都很谦虚。 She is an essentially selfish person.她本质上是个自私自利的人。

6 impaling
钉在尖桩上( impale的现在分词 )
参考例句：
The detective sat down facing John, his eyes impaling the young man. 侦探面对约翰坐下，犀利的目光逼视着这个年轻人。

7 microscopic
adj.微小的，细微的，极小的，显微的
参考例句：
It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。 A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

8 engulfed
v.吞没，包住( engulf的过去式和过去分词 )
参考例句：
He was engulfed by a crowd of reporters. 他被一群记者团团围住。 The little boat was engulfed by the waves. 小船被波浪吞没了。来自《简明英汉词典》

9 maneuver
n.策略[pl.]演习；v.(巧妙)控制；用策略
参考例句：
All the fighters landed safely on the airport after the military maneuver.在军事演习后，所有战斗机都安全降落在机场上。 I did get her attention with this maneuver.我用这个策略确实引起了她的注意。