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Short-Term Hearing Loss Actually Protects Ears

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For a few hours after a particularly loud concert, the ringing in your ears makes it tough to hear. When your friends ask how the show was, you sheepishly ask them speak up so you can catch what they’re saying. This hearing loss, which is most often reversible, doesn’t mean you’re more likely to need a hearing aid later in life. In fact, researchers found the opposite—reversible hearing loss actually protects your ears.

Researchers led by Gary Housley, chair of physiology at the University of New South Wales in Australia, exposed mice to loud noises to learn more about how reversible hearing loss works. Some of the mice had regular ears, but others had ears that lacked a receptor that accepts ATP, a chemical that the cochlea—the spiral shaped auditory part of the inner ear—releases.

The mice without the receptor could listen to loud noises for hours on end without experiencing any short-term effects. It was almost as if they could not perceive a change in sound levels. The mice with the regular ears, however, experienced short-term hearing loss that could last for more than 24 hours, but in the long run protected their ears. And even though the mice without the receptor didn’t seem to notice booming noises, they showed more evidence of permanent hearing loss.

"It's like sun exposure," says Housley. "It's not the acute exposure, but the chronic exposure, that can cause problems years later."

This paper, published in the Proceedings of the National Academy of Sciences (PNAS), reinforces what Housley discovered in a previous study about deafness. In that study he looked at two Chinese families with a mutation in their ATP receptors; if family members worked around loud noises, they experienced accelerated hearing loss.

"Because our hearing sensitivity adapts, we can withstand loud noise, but we can't sense the absolute intensity of the sound and if we exceed the safe sound upper limit, we will damage our hearing—despite this protective adaptation mechanism we have discovered,” Housley says.

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Stones, Bones, and Wrecks
3500-Year-Old Mummy Discovered in Forgotten Egyptian Tomb

As the site of the ancient city of Thebes, the modern-day Egyptian city of Luxor is filled with archaeological treasures. But until recently, two forgotten tombs—both located in the necropolis of Dra' Abu el-Naga, an important non-royal cemetery—hadn’t been fully explored. Now, National Geographic reports that experts have finally excavated these burial sites and discovered a 3500-year-old mummy, along with ornate funerary goods and colorful murals.

While excavating one of the two tombs, known as Kampp 150, experts found linen-wrapped remains that Egypt's Ministry of Antiquities believes belong to either "a person named Djehuty Mes, whose name was engraved on one of the walls ... [or] the scribe Maati, as his name and the name of his wife Mehi were inscribed on 50 funerary cones found in the tomb's rectangular chamber."

In addition to the mummy, archaeologists discovered wooden statues, masks, earthen pots, a cache of some 450 statuettes, and around 100 funerary cones—conical mud objects, which were often positioned outside a tomb's center, and could have served as identifying markers or as offerings—inside Kampp 150.

The Associated Press reported that the second tomb, known as Kampp 161, is thought to be approximately 3400 years old—about 100 years newer than its neighboring chamber—as its design is characteristic of other such structures dating back to the reigns of Amenhotep II and Thutmose IV.

Inside Kampp 161, archaeologists discovered wooden funerary masks, a decorated coffin, furniture shards, and the mural of a festival or party depicting the tomb's unknown resident and his wife receiving ceremonial offerings.

German scholar Friederike Kampp-Seyfried surveyed and numbered both tombs in the 1990s, which is how they got their names, but she did not fully excavate nor enter either one.

Officials celebrated the rediscovery of the tombs on Saturday, December 9, when they publicly announced the archaeological finds. They hope that discoveries like these will entice foreign travelers to visit Egypt, as political unrest has harmed the country's tourism industry in recent years.

“It’s truly an exceptional day,” Khaled al-Anani, Egypt's antiquities minister, said in a statement. “The 18th dynasty private tombs were already known. But it’s the first time" anyone's ever entered them.

Check out some pictures of the newly revealed relics below.

Mustafa al-Waziri, director general of Luxor's Antiquities, points at an ancient Egyptian mural found at the newly discovered 'Kampp 161' tomb at Draa Abul Naga necropolis.
Mustafa al-Waziri, director general of Luxor's Antiquities, points at an ancient Egyptian mural found at the newly discovered 'Kampp 161' tomb at Draa Abul Naga necropolis on the west Nile bank of the southern Egyptian city of Luxor, about 400 miles south of the capital Cairo, on December 9, 2017.
STRINGER/AFP/Getty Images

An Egyptian archaeological technician restores artifacts found at the newly discovered 'Kampp 161' tomb at Draa Abul Naga necropolis in Luxor, Egypt.
An Egyptian archaeological technician restores artifacts found at the newly discovered 'Kampp 161' tomb at Draa Abul Naga necropolis on the west Nile bank of the southern Egyptian city of Luxor, about 400 miles south of the capital Cairo, on December 9, 2017.
STRINGER/AFP/Getty Images

An Egyptian laborer stands next to an ancient Egyptian mural found at the newly discovered 'Kampp 161' tomb at Draa Abul Naga necropolis in Luxor, Egypt.
STRINGER/AFP/Getty Images

Ancient Egyptian wooden funerary masks and small statuettes found in and retrieved from the newly discovered 'Kampp 150' tomb at Draa Abul Naga necropolis in Luxor, Egypt.
A picture taken on December 9, 2017 shows ancient Egyptian wooden funerary masks and small statuettes found in and retrieved from the newly discovered 'Kampp 150' tomb at Draa Abul Naga necropolis on the west Nile bank of the southern Egyptian city of Luxor, about 400 miles south of the capital Cairo.
STRINGER/AFP/Getty Images

[h/t National Geographic]

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Kohske Takahashi, i-Perception (2017)
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fun
Can You Figure Out This Newly Discovered Optical Illusion?
Kohske Takahashi, i-Perception (2017)
Kohske Takahashi, i-Perception (2017)

Ready to have your mind boggled? Take a look at the image above. What shape are the lines? Do they look like curves, or zigzags?

The image, spotted by Digg, is a new type of optical illusion published in the aptly named journal i-Perception. Discovered by Japanese psychologist Kohske Takahashi, it’s called the “curvature blindness illusion,” because—spoiler—the contrast of the lines against the gray background makes our eye see some of the lines as zigzags when, in fact, they’re all smooth curves.

The illusion relies on a few different factors, according to the three experiments Takahashi conducted. For it to work, the lines have to change contrast just at or after the peak of the curve, reversing the contrast against the background. You’ll notice that the zigzags only appear against the gray section of the background, and even against that gray background, not every line looks angled. The lines that look curvy change contrast midway between the peaks and the valleys of the line, whereas the lines that look like they contain sharp angles change contrast right at the peak and valley. The curve has to be relatively gentle, too.

Go ahead, stare at it for a while.

[h/t Digg]

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