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Identification techniques are increasingly relying on medical technology, or biometrics, to provide more personal forms of ID, which are harder to fake. Some feel that this is an invasion of their privacy.
The popping of a balloon happens too fast for us to see in detail. But high-speed photography reveals what is happening at the time of the pop: The stretched skin of the balloon breaks rapidly and violently.
Butterfly on a plant stem
The cellular structure of this sunflower stem includes red vascular areas and blue supportive tissue. This systematic regularity contrasts with the sweeping outline of the butterfly.