Etikettarkiv: science

Are these dots purple or blue?

Every day, humans make dozens of judgements, from deciding whether our clothes match to determining whether a shady character in the street is a threat. Such decisions aren’t based on hard-and-fast rules, a new study reveals. Instead, our concept of “threat”—and even of the color “blue”—is all relative.

To make the find, researchers showed non–color-blind participants a series of 1000 dots ranging from very blue to very purple, and asked them to judge whether each dot was blue. For the first 200 trials, participants saw an equal number of dots from the blue and purple parts of the spectrum, but then the prevalence of blue dots gradually decreased to just a fraction of what it was before. By the end of the study, participants’ interpretation of the colors had changed: Dots that they had thought were purple in the first set of trials they now classified as blue, the authors report  in Science. That is, their concept of the color blue had expanded to also include shades of purple.

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A colloidal quantum dot spectrometer

Illustration: Mary O'Reilly

Illustration: Mary O’Reilly

Researchers have developed a new device for color analyses – a spectrometer- by using something that looks like an ink printer to put special paint on the image tile of a smart phone camera.

Such, lightweight, small and robust spectrometers can be used in space trips to explore far away planets but also to do medical measurements.

Jie Bao & Moungi G. Bawendi: A colloidal quantum dot spectrometer, Nature 2. Juli 2015, vol. 523, 10.1038/nature14576, summery.

Popular science article in Danish 

Colourful plastics – without dyes

Long before humans figured out how to create colours, nature had already perfected the process — think stunning, bright butterfly wings of many different hues, for example.

Morpho didius gets its blue colour as a consequence of the nano structure of its wings

Morpho didius gets its blue colour as a consequence of the nano structures of its wings

Now scientists are tapping into those secrets to develop a more environmentally friendly way to make coloured plastics. Using structure — or the shapes and architectures of materials — rather than dyes, to produce colour.

Article in Danish

Colours help set body´s internal clock

sunsetThe beautiful color of a sunset might be more than just a pretty picture. It could be a signal to our bodies that it’s time to reset our internal clock, the biological ticktock that governs everything from sleep patterns to digestion. That’s the implication of a new study in mice that shows these small rodents use light’s changing color to set their own clocks, a finding that researchers expect will hold for humans, too.

Science article