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Dead at 63, Robin Williams

Where will your wings take you?

Texture by ►CubaGallery on Flickr.

(NASA) Why would a cloud appear to be different colors? A relatively rare phenomenon known as iridescent clouds can show unusual colors vividly or a whole spectrum of colors simultaneously. These clouds are formed of small water droplets of nearly uniform size. When the Sun is in the right position and mostly hidden by thick clouds, these thinner clouds significantly diffract sunlight in a nearly coherent manner, with different colors being deflected by different amounts. Therefore, different colors will come to the observer from slightly different directions. Many clouds start with uniform regions that could show iridescence but quickly become too thick, too mixed, or too far from the Sun to exhibit striking colors. The above iridescent cloud was photographed in 2009 from the Himalayan Mountains in Nepal, behind the 6,600-meter peak named Thamserku.

“Den” of leaves
Dendritic cells get their name from their surface projections, which somewhat resemble the dendrites of neurons, the branchlike extensions that increase the surface of a cell body and receive information from other neurons.
Dendritic cells are found in most tissues of the body, most abundantly in those that interface between internal and external environments, such as the skin, lungs and lining of the gastrointestinal tract. Here, they’re suitably placed to serve their primary function, which is to continuously sample their surroundings for antigens, such as dead cells or invasive microbes. They are a key player in the body’s immune response system.
Once exposed to an antigen, say a virus, the sheets of the dendritic cell entrap it so that it can be degraded by internal lysosomes into peptide fragments and then redisplayed to circulating T cells, which develop the appropriate immune response. 
The image above is an artistic rendering, based on ion abrasion scanning electron microscopy developed at the National Institutes of Health.

Ancient Bird Had Some Feathers Just for Show
German scientists found a new specimen of Archaeopteryx, the 150-million-year-old winged creature thought to represent the transition from dinosaurs to birds, with well-preserved feather markings. The bird, described in the journal Nature, had feathers on its hind limbs that researchers said were more likely used for display than for flight.
Source: nytimes.com

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Wild Sheep
by thibault deresse  (thibaultderesse.tumblr.com)

Soap Film Cube, 2002 by David Goldes

100% ART