Month: November 2018

Enlarge (credit: Aubert et al. 2018)

New radiometric dating identifies the oldest known figurative drawing—not a stenciled outline of a hand or an abstract design, but an actual attempt to depict a real object in an image. As far as we know, a cave wall in Indonesian Borneo was the site for the first time a person drew something, rather than just making abstract marks. The drawing is at least 40,000 years old, based on uranium-series dating of a thin layer of rock deposited on top of the drawing since its creation.

It’s a large animal of some sort, outlined and colored in with reddish-orange pigment, but after 40,000 years, parts of the image are missing. Griffith University archaeologist Maxime Aubert and his colleagues say it appears to be a large hoofed mammal with a spear shaft sticking out of its flank.

Other figurative drawings, as old as 35,000 years, have turned up on the nearby island of Sulawesi, alongside hand stencils dating back to 40,000 years ago. And in Europe, people started representing animals in art around the same time, such as on figurines carved in mammoth ivory from Germany. That means the tradition of representing the world around us in art is ancient around the world, from an island in southeast Asia to western Eurasia.

Enlarge (credit: Chen et al. 2018)

Patients with certain chronic eye diseases, like glaucoma and macular degeneration typically either use inefficient eyedrops, or have to get injections directly into their eyes. A team of researchers wants to replace these with a small patch patients can place on the eye, much like a contact lens. When removed, the patch leaves behind microneedles, which slowly dissolve in the corneal fluid, releasing drugs into the eye as they do. They claim it could make treatments more accessible and less painful for patients, while also providing a more controlled release of the drug.

Replacing injections with a patch

Getting drugs into the eye is a challenge. The most effective solutions tend to be unpleasant and involve actual injections into the eyeball. If doctors deliver the injection in a less horrifying part of the body, it can take a dangerously high initial dose to ensure that enough of the drug actually reaches the eye. Eye drops tend to wash out, and they’re surprisingly inefficient: the eye only absorbs about five percent of the drug most of the time. For some patients, these tradeoffs lead to a choice between needles and blindness.

Some recent ideas have focused on contact lens-like hydrogels that keep drugs on the surface of the eye longer than eye drops to surgically implanting tiny drug reservoirs into the eye. Others have involved microneedles: pyramid-shaped needles just a few hundred micrometers long. Microneedles have been increasingly popular as a less-painful way to get drugs through a patient’s skin without an injection—they’ve been used to deliver vaccinations, local anesthetics, and anti-diabetic medications.

Enlarge (credit: Chen et al. 2018)

Patients with certain chronic eye diseases, like glaucoma and macular degeneration typically either use inefficient eyedrops, or have to get injections directly into their eyes. A team of researchers wants to replace these with a small patch patients can place on the eye, much like a contact lens. When removed, the patch leaves behind microneedles, which slowly dissolve in the corneal fluid, releasing drugs into the eye as they do. They claim it could make treatments more accessible and less painful for patients, while also providing a more controlled release of the drug.

Replacing injections with a patch

Getting drugs into the eye is a challenge. The most effective solutions tend to be unpleasant and involve actual injections into the eyeball. If doctors deliver the injection in a less horrifying part of the body, it can take a dangerously high initial dose to ensure that enough of the drug actually reaches the eye. Eye drops tend to wash out, and they’re surprisingly inefficient: the eye only absorbs about five percent of the drug most of the time. For some patients, these tradeoffs lead to a choice between needles and blindness.

Some recent ideas have focused on contact lens-like hydrogels that keep drugs on the surface of the eye longer than eye drops to surgically implanting tiny drug reservoirs into the eye. Others have involved microneedles: pyramid-shaped needles just a few hundred micrometers long. Microneedles have been increasingly popular as a less-painful way to get drugs through a patient’s skin without an injection—they’ve been used to deliver vaccinations, local anesthetics, and anti-diabetic medications.

Enlarge / MURMANSK, RUSSIA - Russian aircraft carrier Admiral Kuznetsov at the PD-50 floating dry dock of Shipyard 82. (credit: Lev Fedoseyev / TASS via Getty Images)

Russian officials have now acknowledged that the October 29 accident involving Russia’s only aircraft carrier and largest floating dry dock has made continuing the refit of the ship impossible. The dry dock, the PD-50, was the only one available capable of accommodating the 55,000 ton Admiral Kuzntesov. As a result, the completion of the refit of the ship is now delayed indefinitely.

The PD-50, built by a Swedish shipyard in 1980 for the Soviet Union, sank in an uncontrolled “launch” of the Kuznetsov and came to rest on the sloping bottom of the harbor at Murmansk. Two cranes collapsed during the sinking, with one crashing onto the Kuznetsov and leaving a large gash in its hull. And recovering and repairing the PD-50 could take as long as a year.

“We have alternatives actually for all the ships except for Admiral Kuznetsov,” United Ship-Building Corporation chief executive Alexei Rakhmanov told TASS. But the loss of the PD-50 dock “creates certain inconveniences” for future repairs on large capital ships, he acknowledged.” We hope that the issue of the docking of first-rank ships will be resolved in the near future. We are also preparing several alternatives, about which we will report to the Industry and Trade Ministry," Rakhmanov said.

iFixit

On schedule as always, iFixit has documented teardowns of the new Mac mini and MacBook Air and given them each a repairability score. The Mac mini is an improvement over the 2014 model in a few ways. The MacBook Air has some positive points for user serviceability, but it requires a significant teardown to do much.

Starting with the Mac mini, iFixit found that after opening the enclosure, you just have to unscrew and remove the fan to get inside. The logic board can be removed without special tools. Unlike the 2014 Mac mini's RAM, the RAM in this model can be replaced. It's covered by a metal cage, but once you unscrew and remove that, it's easy. The power supply can also be removed and replaced, but you'll want to use a tool for it. On the negative side, the CPU cannot be replaced, and damage to any of the ports would require a logic board replacement.