Word: retinas
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...plants convert sunlight into energy through the process of photosynthesis. Physicists from California's Lawrence Berkeley Laboratory reported that they used such a laser to take a "snapshot" of the chemical reaction that is the first step in visual perception. This reaction, triggered when light hits the retina of the eye, had never before been directly observed. And with good reason. The reaction was clocked by the L.B.L. team at 200 femtoseconds, which are millionths of a billionth of a second. How fast is that? Well, in little more than a second, light can travel all the way from...
Would even the most loving family members want to be forced by the courts to donate a kidney or a retina to an ailing child or sibling? The chemistry of love and courage often inspires one relative to donate organs to another. But to do so is an act of will, born of the impulses of a generous individual -- not the mandate...
...resources and navigate some fishy waters. In the '80s color clinched its victory. The gravity of black-and-white, the hard and durable tones of an anvil, gave way decisively. But color is tricky. Blood shouts, and the smallest patch of yellow adobe pounds hard on the retina. So a generation of photographers have learned to draw that very clamor into a deliberate statement. The hot pinks and fluorescent lime in Alex Webb's pictures of Haiti don't just sizzle inside the frame. They deliver the terms of a paradox: Barbaric rule can operate in the broadest daylight...
...world of biometric security. It is a world in which traditional keys and combination locks could eventually become obsolete. Increasingly, access to buildings, rooms and vaults will be controlled by computerized machines that can recognize personal characteristics of people seeking entrance: fingerprints, blood-vessel arrangements in the eye's retina, voice patterns, even typing rhythms. These biometric machines have special sensors that pick up the characteristics, convert them into digital code and compare them with data stored in the computer's memory bank. Unless the information matches up with the characteristics of authorized persons, entrance is denied...
Perhaps the most sophisticated aid to the handicapped is an eye-tracking system built by Thomas Hutchinson, a University of Virginia engineer. Using a technology developed for jet-fighter pilots, Hutchinson's device measures the reflection of light from the retina to determine where on a computer display the eye is gazing. A person equipped with the eye tracker simply looks at a command on the screen and the computer executes it. "The last thing to go in the body is the eye muscle," says Hutchinson. "With this system we have an opportunity to free minds that are trapped inside...