The phytochrome can then be exposed to a different shade of red light to turn the gene off.

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Even something too small to emit visible light will probably give off radio waves and infra-red radiation (Jupiter does).

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That's because the city has equipped three bus routes with wireless technology that can pull off a trick every commuter has dreamed of: switching a red light to green on command.

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Cars faced off on a two-lane, aluminum track, with a little red light blinking to signal who won.

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Then she came back a little later and reminded me again because she noticed that the red light on my noise reducing headphones was still on, even though I had taken them off my ears and they were hanging loosely around my neck.

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