Based upon the growth layer groups in cementum and dentine of the tooth, the age of the huge Sperm Whale was estimated at 29 years.

根据对牙齿磨片牙骨质和牙齿齿质上的生长层组判断，其年龄约为2 9龄。

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The interface structure of composite consists of core material diffusion layer, chilling solidified layer, directional growth layer, and cellular granular layer.

复合材料界面结构由芯材扩散层、激冷凝固层、方向性生长层和胞状晶粒层组成。

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Bone marrow stem cells can switch roles to produce a protein that promotes growth of the cornea, the transparent layer of the eyeball, scientists have found.

科学家已经发现骨髓干细胞能够转化角色，产生一种蛋白。该蛋白能促进眼角膜(眼球透明层)的生长。

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"The extra layer of growth tells the story of their voyage to the bottom of the seabed, " he added.

CNN: March 11, 2013 -- Updated 1910 GMT (0310 HKT)

Piers, jetties and seawalls with a protective layer of marine growth absorb wave action better.

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When you layer in population growth in U.S. cities (projected to hit 400 million people in the next 40 years), those numbers become larger every year, and the hard reality is that we are running out of water.

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