Mixed news

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''The colour change is not permanent, however. In the absence of UV light, the MUA gradually reverts to its original shape, allowing the nanoparticles to disperse and the images to disappear.'' [source]

Memristor
''Chua set about exploring what this device would do. It was something that no combination of resistors, capacitors and inductors would do. Because moving charges make currents, and changing magnetic fluxes breed voltages, the new device would generate a voltage from a current rather like a resistor, but in a complex, dynamic way. In fact, Chua calculated, it would behave like a resistor that could "remember" what current had flowed through it before ...'' [source]

Urine power
''Using a nickel-based electrode, the scientists can create large amounts of cheap hydrogen from urine that could be burned or used in fuel cells. '' [source]

Computer learns sign language by watching TV
[source]

Rice Concrete Cuts Greenhouse Emissions
''Rice husks form small cases around edible kernels of rice and are rich in silicon dioxide (SiO2), an essential ingredient in concrete. Scientists have recognized the potential value of rice husks as a building material for decades, but past attempts to burn it produced an ash too contaminated with carbon to be useful as a cement substitute.'' [source]