Updated: 8:29 PM UTC, Jul 16, 2017

Wedding Ring And Left Ring Finger - The Explanation

If the wedding ring is worn on the left ring finger, that is because in ancient Rome, doctors thought that a vein connected this finger to the heart. That’s why they called it the "Vena Amoris" vein of love. The name Ring Finger comes from the fact that we put the rings on this finger.

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How Are Stripes On The Toothpaste Made?

The toothpaste stripes are made through a compartment located just at the top of the nozzle exit and drilled with holes. When you press the tube of paste, the dye contained in this compartment is also pressed by the pulp and escapes through the holes, forming stripes.

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Bridges And Resonance - A Physical Phenomenon

It is very dangerous and banned for a battalion of soldiers to cross a bridge marching in step. Indeed the bridge can enter into a resonance, a physical phenomenon that makes the bridge wave and may lead to its destruction.

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Ocean Seaweed And Oxygen Production

Contrary to what people think, it is not forests that produce the most oxygen, but rather ocean seaweed. This organism produces more than two-thirds of the oxygen on the planet.

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Louis Pasteur And The Invention Of Vaccine

It was not Louis Pasteur who invented the principle of vaccine, but Edward Jenner. He had observed that farm laborers in contact with cows developed a natural immunity against human smallpox.

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Autorotation - Landing A Helicopter Without Engine

A helicopter with an engine failure in flight does not always crash. A phase may occur called autorotation. In fact, during the fall air turns the blades, which gives sufficient lift the device to land quickly. This technique is taught to helicopter pilots to deal with emergencies.

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Facebook At Country Level - The second Biggest Population in 2014

If the social network Facebook were a country, it would be the second most populous in the world after China (1.357 billion in 2013) and before India 1.252 billion in 2013). Indeed, as of the third quarter of 2014 Facebook had 1.35 billion monthly active users. Furthermore, at the speed Facebook is growing, It will be the most populous country by the end of 2015.

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Why Are Testicles Outside The Male Body?

Male testicles are outside the body; because spermatogenesis (sperm production) works best at a slightly lower temperature than the body at about 95 °F (35 °C). That is also why the sack shrinks or expands depending on the outdoor temperature.

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Hair And Fingernails Do Not Grow After Death

Hair and nails do not grow after death: it is the skin that shrinks because of the dehydration of the body causing retraction of the skin near hair and nail roots. This is why we have the impression that they have grown.

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Morphine and Morpheus - The Greek God Of Dreams

Morphine alkaloid commonly used against pain derives its name from Morpheus, the Greek god of dreams. He possesses ability to make mortals and other gods fall asleep by lightly touching them with a leaf of the opium poppy. Morpheus can also mimic any human form and appear in dreams.

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There's A Glow-In-The-Dark Blue Phenomenon In San Diego

On the beaches of San Diego in September, you can admire the beautiful evening light-blue waves. This is due to a species of algae that, when shaken, creates a phenomenon of bioluminescence, and even allows surfers to practice their sport at night.

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A Mushroom That Should Not Be Served With Wine

The shaggy mane, also know as the shaggy ink cap or lawyer's wig is an edible mushroom that taken alone is safe for humans. However, it should not be eaten with alcohol.

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