听力文本

Ah yes.The ol' fluoride rinse at the dentist.Not pleasant.
But hey, good for your teeth, right?
Well now materials scientists have been able to figure out why—by mapping the nanostructure of tooth enamel.
If you zoom way in, tooth enamel looks almost like the weave of a basket.
"Where each thread is made from thousands of nanowires."
Derk Joester, of Northwestern University.
And in between those crystalline nanowires,Joester and his colleagues discovered a sort of amorphous glue.
And that's where the fluoride hangs out, helping to stave off an acid attack of the enamel—in other words, a cavity.
But the researchers found something that works even better than fluoride: iron.
And they found it in beaver teeth.
"Beavers don't get caries.
Chewing through wood is a very good way to clean your teeth."
But another reason, they say, is the iron-enriched glue in beaver enamel—which was even more acid-resistant than fluoride-treated enamel.
The findings are in the journal Science.
Of course iron-rich enamel comes with an unfortunate side effect: reddish-brown teeth.
But Joester says future human dental treatments that employ iron might find a way around that.
"We have the entire periodic table to play with minus a few things that are not too healthy.
So I'm sure we can come up with a way to do what the beaver does but do it better and do it in a way that still maintains a nice smile."

参考译文
没错，这是牙医洗牙用的含氟漱口水fuffZv0BV5F8Wl#hsNlu。确实够闹心的cWIO=[)lQ*B1。
但毕竟对你的牙齿有益不是吗?
现在材料科学家们通过绘制牙釉质的纳米结构已经知晓其中的原因QZy~g0%WhH。
如果放大牙釉质，它与篮子的纹理非常相近1YqO1V(cxx~soQO-D6=G。

“每条线都由成千上万的纳米线条组成U-C]5nOl%MmI_[IOZ。”
西而在这些晶状纳米线中，乔斯特尔和同事们发现了一种非固定形状的胶质3cCvB9.wL6r8!32k-。
而氟化物就在这里聚集，帮忙延缓阻挡牙釉质的酸蚀—换句话说抑制蛀牙HIrraO[4Ez。
但研究人员发现了一样比氟化物效果更好的物质：那就是铁jaTwM6(V5km0Mu]Ow。
他们是在海狸的牙齿中发现了它ICS7%1hy[k_。
“海狸不会患上龋齿_cBMJ5RxZVS2^。
咀嚼木头是一种很好的清洁牙齿的方式wX(@(xkHE6HV。”
但他们称另一个原因则是海狸牙釉质中富含铁的胶质—相比氟这种牙釉质在耐酸性上更胜一筹y=wY*JgA9k8G.#f。
这项研究已经在《科学》杂志上发表OzxsofgWAY。
当然富含铁的牙釉质有着副作用：那就是会使牙齿变成红褐色Gl].U&wzU=Pa。
但乔斯特尔表示未来牙齿治疗方面会采用铁进行，应该可以找到相关解决办法)iL)2~[Qgo。
“我们有整个周期可以解决那些并不健康的治疗手段EDfh-+xAfoA)b&p^@=|*。
所以我相信我们能想出办法像海狸那样，而且在继续保持洁白笑容这方面会做得更好eyUgfL&v)^[s18n+EY。”

译文为可可英语翻译，未经授权请勿转载！

重点讲解

1.figure out 弄明白；解决；想出

They're trying to figure out the politics of this whole situation.
他们正试图弄明白整个情形背后的权术争斗#e,-2o~%jWS。

I can't figure out what he was hinting at.
我想不出他在暗示什么]8Y8mq-SfZ。

2.hang out 伸出

We can just hang out and have a good time.
我们可以只是闲逛一下，开开心IZQ^TbK@-Y~)~5PL。

I often used to hang out in supermarkets.
我过去经常在超市里逛个没完sjskq8sMxmlM3。

3.come up with 追赶上；提出；想出

Let's fingerprint the canoe, see if we come up with anything.
让我们提取一下独木舟上的指纹，看看能不能有什么发现b!B|AMGiHl.x354Nsv。

Howard Wilkinson has come up with an absolute corker of an idea.
霍华德·威尔金森想出了一个绝佳的主意VQc#,Zhl1%n^=6m_G)y。