This wouldn't matter in a lower latitude, because the body can synthesize vitamin D if exposed to ultraviolet sun rays.
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These are physical blockers which protect the skin by either deflecting sun rays or reflecting them away from the skin, like a mirror.
Sun rays are, as expected, absolutely no problem and we have to admit that on first sight we thought the device had a sticker affixed to its front -- its that good at reproducing printed materials.
But on this point Iannelli is not convinced: "At the moment, solar panels are not fit for purpose in the UAE ... the dust and the sand in the atmosphere prevent (sun) rays from hitting the panels efficiently ... and the high temperatures also reduce performance, " he says.
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Exposure to the sun's rays normally generates Vitamin D in the skin, but applying sun block stops that process.
If such heaters were covered with thermoelectric generators the sun's rays could be put to sequential use.
When skin (the body's largest organ) is exposed to the sun's rays, free radicals can develop, Katz explained.
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Volcanoes spew out huge quantities of dust, which cools the earth by shielding it from the sun's rays.
Sepp Fiedler, of Solar Lifestyle, the company behind the idea, told CNN that the bins were powered by the sun's rays.
Traditionally these are large pieces of polished metal, steered by electric motors to keep the sun's rays focused on the cell.
Top of the list is a solar shade, a gigantic umbrella in space that would shield the Earth from the sun's rays.
Equipped with computer-controlled blinds, these walls could, depending on temperature and the need for light, insulate the house or fill it with the sun's rays.
As they describe in Nanoscale Research Letters, they have invented a way of concentrating the energy in the sun's rays without the need for mirrors.
Bringing more light than a traditional window that can crack or leak during typhoon season, the bottle bulbs refract the sun's rays to create 55-watts worth of light.
The idea is to inject clouds of material into the stratosphere, creating a thin haze and deflecting some of the sun's rays away from the Earth, at least temporarily.
Nevada Solar One uses a parabolic trough design, in which curved mirrors, 16 feet from top to bottom, concentrate the sun's rays onto a glass tube with a steel bar at its center.
It's early evening in the Bitterroot Valley, and the sun's rays mingle with plumes of smoke rising from the mountains as firefighters load up their trucks before heading out for the overnight shift.
Among the challenges is modifying sensors designed to detect the heat from an incoming warhead so they can spot the much-cooler satellite, which has no heat source and is warmed only by the sun's rays.
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Early of the Lawrence Livermore National Laboratory, California, proposed siting a vast, 2000 km-wide glass deflecting panel at the "inner Lagrange point" between the Earth and the sun, the latter diverting the sun's rays away from the Earth's atmosphere.
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The all-carbon formula doesn't need to be thickly spread to do its work, and it simply lets visible light through -- it could layer on top of a traditional solar cell to catch many more of the sun's rays.
And the nuclear-winter hypothesis (that the smoke from fires caused by a global nuclear war would blot out the sun's rays and thus cool the earth catastrophically) owes its origin, at least in part, to observations of a planet-wide dust storm on Mars.
What we do is we get every quilting circle and church group in America to start making Mylar screens and sewing them together like quilt, and then we put them into the ocean, where they reflect the sun's rays and keep the water underneath cooler.
Dr. Costarelis advises his patients to eat a nutrient-rich diet and stay out of the sun, because UV rays damage hair.
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So many are reporting in the coming weeks so it will be very interesting to see what they say about the sun and all its rays going forward.
The agency added that a lack of sunshine had also failed to improve the situation as the sun's UV rays would usually kill some of the bacteria found in the sea.
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Initially, the idea was to use plastic flexible displays (as evidenced by previous XO 3.0 renders), but degradation caused by the sun's UV rays and plastic's easily scratched surface forced the company to switch gears and use glass instead.
Each day, when the first rays of sun warm its ochre walls, the doline comes alive with the sounds of the red-green macaw, as formations of these exotically-plumaged parrots dive and wheel below the lip, periodically alighting en masse to bicker, preen and survey their domain.
Midbite into an ostrich burger at lunch one day, I watched the vanguard of an elephant herd emerge onto the lagoon shore, about 100 yards away, and each evening I trained my binoculars on the red lechwe gathered in the shallows, their russet coats burnished by the sun's slanting rays.
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