GM silkworms bred to spin fluorescent
(Phys.org) —Scientists in Japan have genetically engineered silkworms to create red, green or orange silks that glow under fluorescent lights.
(Phys.org) —Scientists in Japan have genetically engineered silkworms to create red, green or orange silks that glow under fluorescent lights.
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The thylacine, that famous extinct Australian icon colloquially known as the Tasmanian Tiger, is revealed to have been only about half as big as once thought—not a "big" bad wolf after all.
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In a subterranean vault in a suburb of Paris lies a small, rarely seen metal cylinder known as Le Grand K.
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The world has one official kilogram against which all other country's kilograms are measured and scales calibrated.
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Officials with the General Conference on Weights and Measures (CGPM) have announced that at a meeting to be held next week, four of the base units used in the metric system will be redefined. The four units under review are ...
Researchers from the Universities of Bremen and Innsbruck have shown in a recent study that the further melting of glaciers cannot be prevented in the current century—even if all emissions were curtailed. However, due to ...
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Using a state-of-the-art device for measuring mass, researchers at the National Institute of Standards and Technology (NIST) have made their most precise determination yet of Planck's constant, an important value in science ...
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In a secure vault in the suburbs of Paris, an egg-sized cylinder of metal sits in a climate-controlled room under three glass bell jars. It is the mass against which all other masses in the world are measured - by definition ...
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The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal to the mass of one liter of water. The avoirdupois (or international) pound, used in both the Imperial system and U.S. customary units, is defined as exactly 0.45359237 kg, making one kilogram approximately equal to 2.2046 avoirdupois pounds.
In everyday usage, the mass of an object given in kilograms is often referred to as its weight, which is the measure of the gravitational force—or heaviness—of an object. Weight given in kilograms is technically the non‑SI unit of measure known as the kilogram-force. The equivalent unit of force in the avoirdupois system of measurement is the pound-force. In strict scientific contexts, forces are typically measured with the SI unit newton.
The kilogram is the only SI base unit with an SI prefix as part of its name. It is also the only SI unit that is still directly defined by an artifact rather than a fundamental physical property that can be reproduced in different laboratories. Four of the seven base units in the SI system are defined relative to the kilogram so its stability is important.
The International Prototype Kilogram is kept in the custody of the International Bureau for Weights and Measures (BIPM) who hold it on behalf of the General Conference on Weights and Measures (CGPM). After the International Prototype Kilogram had been found to vary in mass over time, the International Committee for Weights and Measures (CIPM) recommended in 2005 that the kilogram be redefined in terms of a fundamental constant of nature. At its 24th meeting the General Conference on Weights and Measures (CGPM) agreed in principle that the kilogram should be redefined in terms of the Planck constant, but deferred a final decision until its next meeting, scheduled for 2014.
This text uses material from Wikipedia, licensed under CC BY-SA