In two of the trials, the box was dark for 12 minutes and then illuminated for 48 minutes with either long-wavelength red light or short-wavelength blue light directed at the subjects' corneas. (Light color is determined by its wavelength.) The box was dark in a control experiment.

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The photoswitch turns the glutamate receptor on or off by changing its shape depending on the wavelength of light used a technique that's been shown to induce light sensitivity in blind mice.

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The new map is a smart byproduct of the European Space Agency (Esa) telescope's main mission which is to survey the Cosmic Microwave Background, or CMB - a pervasive but faint glow of long-wavelength radiation that comes to us from the very edge of the observable Universe.

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The energy of a packet of light -- or "photon" -- is inversely proportional to its wavelength.

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Now they have something that works like a flatbed document scanner, with a scanning head containing either six or 12 light-emitting diodes, each emitting light of a specific wavelength between 350 nanometres (ultraviolet) and 800 nanometres (infra-red).

ECONOMIST: Monitor

Basically, it comes down to this: in addition to the usual frequency and wavelength details that distinguish different types of signals, there are other features that influence the shape or form of the waves best suited to certain types of transmissions.

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