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Sometimes women and men break a nail working on a tough task. Because our keratin claws are no match for the club-like appendages¹ of a critter called the peacock mantis² shrimp³. They can hammer through crab⁴ exoskeletons and even mollusk⁵ shells to find a meal. They can even smash through glass.

Researchers drilled down to the nanoscale to determine what makes the tiny shrimp clubs so tough. Turns out there are three sections to the club. There’s an extremely hard impact region made of hydroxyapatite, or HA. That’s also found in vertebrate bones and teeth.

The HA is backed by an array of rods of chitosan, another hard substance found in crustacean⁶ and insect exoskeletons. The chitosan array protects against fractures. The sides of the claw are less stiff, and act sort of like shock-absorbers. The research is in the journal Science.

The resulting composite is optimized⁷ for high-velocity offensive strikes. It can inflict⁸ maximum damage with minimal⁹ internal cracks.

In an accompanying commentary in the journal, scientists say that understanding the structure could have implications in, for instance, designing lighter¹⁰ armor that’s less likely to fracture. Or perhaps an improved crab mallet¹¹.

Thanks for the minute for Scientific Americans 60 second Science, I am Cynthia Graber.

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1 appendages
n.附属物( appendage的名词复数 )；依附的人；附属器官；附属肢体（如臂、腿、尾等）
参考例句：
The 11th segment carries a pair of segmented appendages, the cerci. 第十一节有一对分节的附肢，即尾须。来自辞典例句 Paired appendages, with one on each side of the body, are common in many animals. 很多动物身上有成对的附肢，一侧一个，这是很普遍的现象。来自辞典例句

2 mantis
n.螳螂
参考例句：
Praying mantis has two powerful claws like sharp knives.螳螂有一对强壮的爪子，它们像锋利的刀。 In her mind,it was a female mantis,devouring her mates.她的意识中，是一只雌螳螂正吞咽她的配偶。

3 shrimp
n.虾，小虾；矮小的人
参考例句：
When the shrimp farm is built it will block the stream.一旦养虾场建起来，将会截断这条河流。 When it comes to seafood,I like shrimp the best.说到海鲜，我最喜欢虾。

4 crab
n.螃蟹，偏航，脾气乖戾的人，酸苹果；vi.捕蟹，偏航，发牢骚；vt.使偏航，发脾气
参考例句：
I can't remember when I last had crab.我不记得上次吃蟹是什么时候了。 The skin on my face felt as hard as a crab's back.我脸上的皮仿佛僵硬了，就象螃蟹的壳似的。

5 mollusk
n.软体动物
参考例句：
I swear I have never seen such a mollusk with thorns all over its body.我敢发誓我从来没有见过这种全身长满棘刺的软体动物。 The colour varies with the mollusk and its environment.颜色因母体及其环境的不同而异。

6 crustacean
n.甲壳动物；adj.甲壳纲的
参考例句：
Seafood is a valuable lobster crustacean section.名贵海珍品龙虾属甲壳科。 The illustrious Cuvier did not perceive that a barnacle was a crustacean.大名鼎鼎的居维叶也未看出藤壶是一种甲壳动物。

7 optimized
adj.最佳化的，（使）最优化的v.使最优化，使尽可能有效( optimize的过去式和过去分词 )
参考例句：
We are often asked whether consumer Web sites should be optimized for beginners or intermediates. 我们常常被问到这样的问题：消费类网站究竟应该为新手而优化，还是应该为中间用户而优化？来自About Face 3交互设计精髓 GOOGLE Advertising optimized sequence, greatly increasing the advertising effect. 优化了GOOGLE广告位排列顺序，大大增加了广告效果。来自互联网

8 inflict
vt.(on)把…强加给，使遭受，使承担
参考例句：
Don't inflict your ideas on me.不要把你的想法强加于我。 Don't inflict damage on any person.不要伤害任何人。

9 minimal
adj.尽可能少的，最小的
参考例句：
They referred to this kind of art as minimal art.他们把这种艺术叫微型艺术。 I stayed with friends, so my expenses were minimal.我住在朋友家，所以我的花费很小。

10 lighter
n.打火机，点火器；驳船；v.用驳船运送；light的比较级
参考例句：
The portrait was touched up so as to make it lighter.这张画经过润色，色调明朗了一些。 The lighter works off the car battery.引燃器利用汽车蓄电池打火。

11 mallet
n.槌棒
参考例句：
He hit the peg mightily on the top with a mallet.他用木槌猛敲木栓顶。 The chairman rapped on the table twice with his mallet.主席用他的小木槌在桌上重敲了两下。