常速英语

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Alright so now we're going to go into a little bit more detail on Dengue virus since it's once the subjects of our talk today. If you rotate it very carefully, I'm going to highlight for you the penta...

好了，现在我们将更详细地介绍登革热病毒，因为它曾经是我们今天演讲的主题。如果你非常小心地旋转它，我将为你突出显示每个顶点的五边形，所以它就在那里。如果你非常敏锐，你可以发现一个三重对称轴。这对应于每个三角形面的中心。现在，令人惊讶的是，整个...

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It's just like a white desert for as far as you can see. There is absolutely nothing and you come back and it's overwhelming. Between 2016 and 2018 Dr Tim Heitland spent 14 months in antarctica ...

就像 一望无际的白色沙漠。 有 什么都没有，你回来了 这让人不知所措。 2016 年至 2018 年期间，Tim Heitland 博士 作为 一个 12 人的德国研究团队。 当他恢复正常生活时 毡 不同，我做的第一件事...

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Like all young mammals, human infants depend on milk for nutrition. Milk is rich in lactose, a disaccharide made from two sugar molecules. Lactose cannot be directly absorbed in the small intestine. T...

像所有年轻的哺乳动物一样，人类婴儿依赖牛奶获取营养。牛奶富含乳糖，这是一种由两个糖分子组成的二糖。乳糖不能在小肠中直接吸收。为了消化乳糖，哺乳动物会产生乳糖酶。现在乳糖与乳糖酶的活性位点结合。该酶水解乳糖并产生两种单糖，葡萄糖和半乳糖。然后...

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Mutations arise at random in a population. Suppose a mutation arises that causes adults to produce lactase in a population that doesn't have any dairy cows. Adults don't drink milk, so producing the l...

突变在群体中随机出现。假设出现突变，导致成虫在没有任何奶牛的种群中产生乳糖酶。成年人不喝牛奶，因此产生乳糖酶是浪费能源。突变丢失或仍然罕见。如果同样的突变发生在人们驯化奶牛的人群中，成年人可以喝牛奶而不会生病，并从牛奶中的糖分中获得能量。他...

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Human existence is scary and confusing. A few hundred thousand years ago, we became conscious and found ourselves in a strange place. It was filled with other beings. We could eat some; some cou...

人类的存在是可怕和令人困惑的。 几十万年前，我们开始清醒，发现自己在一个陌生的地方。 里面到处都是其他生物。我们可以吃一些;有些人可以吃掉我们。 有我们可以喝的液体;我们可以用来制造更多东西的东西。 白天的天空有一个...

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Polymerase chain reaction-- or PCR-- uses repeated cycles of heating and cooling to make many copies of a specific region of DNA. First, the temperature is raised to near boiling, causing the double s...

聚合酶链反应 （PCR） 使用重复的加热和冷却循环来制作 DNA 特定区域的许多副本。首先，将温度升高到接近沸点，导致双链 DNA 分离或变性成单链。当温度降低时，短 DNA 序列（称为引物）与靶 DNA 序列上的互补匹配结合或退火。 ...

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So this squid is a nocturnal animal. And so what we've done is we put this poor guy in his water during the day. And he doesn't like it. So he looks kind of uncoordinated, he looks a...

所以这个鱿鱼 是一种夜行动物。 因此，我们所做的是 把这个可怜的家伙放进他的水里 白天。 他不喜欢这样。 所以他看起来很善良 的 uncoordinated， 他看起来有点紧张 因为他不应该 白天...

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Humans have existed for millions of years, as part of nature. But then, something changed. And in an incredibly short amount of time.. ..We terraformed this planet and designed it to fit our nee...

人类作为自然的一部分已经存在了数百万年。 但后来，情况发生了变化。而且在极短的时间内.. ..我们对这个星球进行了地球化改造，并对其进行了设计以满足我们的需求。 据我们所知，我们是第一批觉醒并完全接管一个星球的生物。 ...