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先有鸡后有蛋

2017-06-09 2页 doc 6KB 24阅读

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先有鸡后有蛋先有鸡后有蛋   What came first, the chicken or the egg? Scientists in Britain think it was probably the chicken, after using new computer technology to try and crack the age-old riddle.   Researchers at the Universities of Sheffield and Warwick, in northern and central En...
先有鸡后有蛋
先有鸡后有蛋   What came first, the chicken or the egg? Scientists in Britain think it was probably the chicken, after using new computer technology to try and crack the age-old riddle.   Researchers at the Universities of Sheffield and Warwick, in northern and central England, say the secret lies in the eggshell -- specifically the vital role played by a chicken protein in forming it.   Scientists already knew that the protein, ovocledidin-17 (OC-17), plays a part in eggshell formation, but the new technology allowed the team to demonstrate exactly how the protein makes it happen.   In a computer simulation, the OC-17 protein acted as a catalyst to kickstart the formation of crystals that make up an eggshell by clamping itself on to calcium carbonate particles.   The OC-17 protein then dropped off when the crystal nucleus was large enough to grow on its own, freeing up the protein to start the process again.   Eggshells are created when this happens many times over within a short period of time.   "Understanding how chickens make eggshells is fascinating in itself but can also give clues towards designing new materials and processes," said Professor John Harding from Sheffield University, one of the authors of the research.   "Nature has found innovative solutions that work for all kinds of problems in materials science and technology -- we can learn a lot from them," he added.   究竟是鸡生蛋,还是蛋生鸡?英国科学家在应用最新电脑技术尝试破解这一古老谜后宣称,很有可能是先有鸡后有蛋。   位于英格兰北部谢菲尔德大学和中部华威大学的研究人员称,这一秘密源自蛋壳---特别是鸡体内的一种蛋白质在形成蛋壳的过程中扮演着关键的角色。   科学家之前已发现这种名为OC-17的蛋白质与蛋壳形成有关,但新技术使研究小组可以精确展示这种蛋白质如何促进了蛋壳的形成。   在计算机模拟中,蛋白质OC-17类似于一种催化剂,通过作用于碳酸钙,促进了构成蛋壳的晶体的形成。   在晶核足够大,可以自行生长之后,蛋白质OC-17就逐渐消退了,之后便可以投身于下一次的转化过程。   当这一过程在短时间内多次重复之后,蛋壳就形成了。   研究的作者之一、谢菲尔德大学的约翰•哈丁教授说:“弄清楚鸡蛋壳是如何长出的非常有趣,而且还有助于研发新和新。”   他补充说:“大自然为材料科技的所有难题都准备好了创新性的解决办法,我们从中可以学到很多。”                
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