Yu Youzhen, a Chinese millionaire, works as a street sweeper for the sanitation department to set an example for her children.
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MIT has developed a camera that captures the speed of light at a trillion frames per second.
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The Simpsons are responsible for popularizing the word 'meh'.
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Elephants are among the most emotional creatures in the world - they have even been known to rescue other animals, such as trapped dogs.
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Passengers on the Beijing subway can pay with plastic bottles.
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