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Did you know?

The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).

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Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.

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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

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In Eastern Europe and Russia, interferon is administered intranasally in varied doses for the common cold and influenza. It is claimed that this treatment can lower the risk of infection by as much as 60–70%.

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Acetaminophen (Tylenol) in overdose can seriously damage the liver. It should never be taken by people who use alcohol heavily; it can result in severe liver damage and even a condition requiring a liver transplant.

The sea urchin Diadema on a coral reef. Feeding by Diadema appears to play a key role in the interac The sea urchin Diadema on a coral reef. Feeding by Diadema appears to play a key role in the interac
The Sun as it appears from the surface of Earth during the middle of the day The Sun as it appears from the surface of Earth during the middle of the day
Photograph of the retina of the eye. The optic disk appears yellow and the retinal arteries radiate Photograph of the retina of the eye. The optic disk appears yellow and the retinal arteries radiate
The Sun as it appears from the surface of the Earth at sunrise. The Sun as it appears from the surface of the Earth at sunrise.
In this painting evangelist George Whitefield appears to be cross-eyed. This is no fault of John Wol In this painting evangelist George Whitefield appears to be cross-eyed. This is no fault of John Wol
Ecological restoration Ecological restoration
Video: Effect of blood chemistry - stimuli, hyperventilation response and hypoventilation response

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