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Journalism of Courage
In making a new type of material that can trap and channel tiny amounts of liquid, researchers at the Massachusetts Institute of Technology found inspiration in a beetle. Scientists call slick, water-repelling surfaces— like raincoats and just-waxed car hoods—hydrophobic: afraid of water. Some materials repel water so well that they are known as superhydrophobic; droplets bead up into spheres that barely touch the surface. Similarly, something that almost instantly attracts and disperses water is superhydrophilic. Michael F. Rubner, a materials scientist, and Robert E. Cohen, a chemical engineer, wanted to make a material with abutting patterns of superhydrophobia and superhydrophilicity.
In 2001, they read in the journal Nature that the dime-size Stenocara beetle in the Namib Desert of Africa did just that. Oxford University scientists described how tiny superhydrophilic bumps on the back of the beetle gathered moisture out of the wisps of morning fog. The water droplets then slipped off the bumps into superhydrophobic channels and rolled into the beetle’s mouth. ‘‘It provided a template of success for us,’’ Dr Cohen said. Last month, in the journal Nano Letters, Cohen and Rubner reported success in mimicking the beetle, finding a way to print superhydrophilic patterns on a superhydrophobic surface.
Blue-tinted sunglasses can cause problems
Those cool, blue-tinted shades worn on bright summer days might be fashionable, but local eye experts are warning that it may not be the best choice of lens for the long-term health of your eyes. ‘‘Blue tint emits ultraviolet light, and that is what sunglasses are supposed to block,’’ said Dr Eleanor E. Faye of Lighthouse International in Manhattan, a 100-year-old nonprofit organisation that promotes the rehabilitation of vision impairment and blindness. ‘‘Sunglasses really prevent the eye from constantly being barraged with ultraviolet light … which … is harmful to the retina and may cause damage like macular degeneration.’’ Janet R. Sparrow, professor of ophthalmic science at Columbia University Medical Center, said blue light excites pigments in the retinal cells to form unstable oxygen molecules that harm the macular cells responsible for fine eyesight used for reading and other close work. ‘‘Naturally, these cells have a mechanism that gets rid of unwanted compounds, but in this case these particular compounds are unusual, and the cell doesn’t have a mechanism for how to deal with it. This doesn’t happen with red light or yellow light,’’ said Sparrow, who is researching blue light as a cause of age-related macular degeneration, including Stargardt’s disease, in which these blue-light-sensitive compounds form at an accelerated rate, causing damage to retinal cells and leading to vision loss. —LAT-WP
Getting older can mean becoming happier
Is youth really the happiest time of life? Researchers who surveyed younger and older adults found that both believe that, as a general rule, happiness declines with age. But when it came to their own experience, the older adults described themselves as happier than the younger people did. The study, led by Heather P. Lacey of the Veterans Affairs Ann Arbor Healthcare System and the University of Michigan, appears in The Journal of Happiness Studies. The researchers asked 540 people, one group ages 21 to 40 and the other over 60, to assess their current state of happiness. They were also asked, depending on their age, to recall or predict how happy they were at 30 and again at 70. Most said that with age came decreasing happiness. But the findings from this study, as well as others that the researchers cited, suggested that there was little evidence to support that. ‘‘Beliefs about aging are important,’’ the researchers write. ‘‘If younger adults mispredict old age as miserable, they may make risky decisions, not worrying about preserving themselves for what they predict will be an unhappy future.’’ —NYT
