Innovation & Technology
Weekly Roundup

This is the online version of the latest UNU-MERIT I&T Weekly which is sent out by email every Friday. If you wish to subscribe to this free service, please submit your email address in the box to the right.

This week's headlines:

Tiny robots crawl through mouse's stomach to heal ulcers
August 16, 2017

Tiny robotic drug deliveries could soon be treating diseases inside your body. For the first time, micromotors - autonomous vehicles the width of a human hair - have cured bacterial infections in the stomachs of mice, using bubbles to power the transport of antibiotics.

In mice with bacterial stomach infections, researchers from the University of California San Diego used the micromotors to administer a dose of antibiotics daily for five days. At the end of the treatment, they found their approach was more effective than regular doses of medicine.

The tiny vehicles consist of a spherical magnesium core coated with several different layers that offer protection, treatment, and the ability to stick to stomach walls. After they are swallowed, the magnesium cores react with gastric acid to produce a stream of hydrogen bubbles that propel the motors around. This process briefly reduces acidity in the stomach. The antibiotic layer of the micromotor is sensitive to the surrounding acidity, and when this is lowered, the antibiotics are released.

After 24 hours, the stomach acid of the mice returned to normal levels, and as the micromotors are mostly made of biodegradable materials, they were dissolved by the stomach, leaving no harmful residues. The next steps are to look at a larger animal study, followed by eventual trials in humans.

Full story: New Scientist / Nature Communications Back to top

NASA's ambitious plan to save Earth from a supervolcano
August 16, 2017

Lying beneath the tranquil settings of Yellowstone National Park in the US lies an enormous magma chamber. It's responsible for the geysers and hot springs that define the area, but for scientists at NASA, it's also one of the greatest natural threats to human civilisation as we know it: a potential supervolcano.

When NASA scientists came to consider the problem, they found that the most logical solution could simply be to cool a supervolcano down. A volcano the size of Yellowstone is essentially a gigantic heat generator, equivalent to six industrial power plants. Yellowstone currently leaks about 60-70% of the heat coming up from below into the atmosphere, via water which seeps into the magma chamber through cracks. The remainder builds up inside the magma, enabling it to dissolve more and more volatile gases and surrounding rocks. Once this heat reaches a certain threshold, then an explosive eruption is inevitable.

But if more of the heat could be extracted, then the supervolcano would never erupt. NASA estimates that if a 35% increase in heat transfer could be achieved from its magma chamber, Yellowstone would no longer pose a threat.

NASA believe the most viable solution could be to drill up to 10km down into the supervolcano, and pump down water at high pressure. The circulating water would return at a temperature of around 350C, thus slowly day by day extracting heat from the volcano. Such a plan could be potentially applied to every active supervolcano on the planet, and NASA's scientists are hoping that their blueprints will encourage more practical scientific discussion and debate for tackling the threat.

Full story: BBC News Back to top

Self-propelling droplets creep towards heat to cool microchips
August 07, 2017

Usually, cool water moves away from hot areas - but make the droplets small enough and the opposite happens. The effect may help us cool electronic devices, with tiny droplets of water propelling themselves to the hotter areas before evaporating and cooling the surface.

Fluids tend to move when there is an imbalance of surface tension - the force that helps you blow soap bubbles. Temperature can cause surface tension to change, with fluids generally flowing away from warmth. But get down to the nanoscale and the effect is reversed. Using computer simulations, researchers from the Indian Institute of Technology in Kharagpur have found that nanometre-sized water droplets on water-repellant surfaces move towards the heat.

The effect is down to an increase in Van der Waals forces, which attract molecules in the droplet towards molecules in the surface on which it is resting. In this case, the enhanced force pulls water molecules out of the droplet, causing them to evaporate. Although this force is present both on the hot and cold side of a droplet, the molecules on the hot side are more energetic so they can evaporate much faster.

As they evaporate, there's a lower concentration of molecules on the warmer side, so those from the cooler side start moving toward the heat. That localised cooling, which increases the local surface tension where the droplet touches the surface, causing the droplet to slide along towards the hotter region.

Full story: New Scientist / Nanoscale Back to top

Chinese quantum satellite sends 'unbreakable' code
August 10, 2017

China has sent an 'unbreakable' code from a satellite to the Earth, marking the first time space-to-ground quantum key distribution technology has been realised.

China launched the world's first quantum satellite last August, to help establish 'hack proof' communications.

The satellite sent quantum keys to ground stations in China between 645 km and 1,200 km away at a transmission rate up to 20 orders of magnitude more efficient than an optical fibre, according to scientists from the Chinese Academy of Sciences.

Any attempt to eavesdrop on the quantum channel would introduce detectable disturbances to the syste. Once intercepted or measured, the quantum state of the key will change, and the information being intercepted will self-destruct, according to the researchers.

Full story: Reuters Back to top

Hydrogen fuel could become a viable energy alternative thanks to alloy
August 07, 2017

Researchers at the US Army Aberdeen Proving Ground Research Laboratory were developing a high-strength aluminium alloy when they made a startling discovery. During routine testing of the alloy, water poured over its surface started bubbling and producing hydrogen gas.

This is an unusual reaction - typically, aluminium exposed to water oxidises, creating a protective barrier to prevent further reactions from occurring. In this case, though, the hydrogen-producing reaction just kept going, signalling the possibility of a portable, affordable source of hydrogen for fuel cells and other energy applications.

This serendipitous discovery has the potential to reinvigorate the hydrogen fuel industry. This would make hydrogen fuel cells much easier to use since there would be no need to pressurise and transport hydrogen gas for use. Instead, simple, stable tanks of water and pieces of aluminium would be all you'd need.

Previous attempts to drive the aluminium/water reaction required catalysts or high temperatures, and they were slow. Ultimately, they were only about 50% efficient, and obtaining the hydrogen took hours. In contrast, the method that uses this new alloy takes less than three minutes to achieve almost 100% efficiency.

Full story: Science Alert Back to top

New algorithms will fix your photos before you even take them
August 04, 2017

New algorithms developed by Google and MIT engineers make it possible for smartphones to process and retouch photos in real-time, before you've even hit the shutter button - so they can fix your shoddy photography before it happens.

Machine learning networks were set to work on a database of 5,000 sample images improved by five professional photographers, teaching the software how to tweak a picture to get it looking its best. The real innovation in this case is making the resulting algorithms efficient and fast enough to apply the retouching while you're still framing your selfie, and according to the researchers that speed of operation opens up a host of potential uses.

The engineers developed algorithms that can perform the image processing on a low-res version of the picture coming through the camera viewfinder, then scale up the results without the quality getting ruined along the way. The low-res images are upscaled by outputting them not as actual images but as formulae that could then be applied to the high-res versions - expressing the changes through mathematics rather than as actual pixels. Finally, splitting the output from the retouched, low-res photos into a grid meant that every pixel in the final high-res image had four formulae combining to tell it what colour it should be.

When compared with a machine learning system that uses full-resolution versions of the photos throughout the process, the new approaches uses just a hundredth of the memory. All of which means the picture you see on your camera screen as you frame your shot can be processed very quickly, even as you're moving it around. The engineers say they can tweak the system to create different styles of shot to be used for different purposes beyond your next Facebook post.

Full story: Science Alert Back to top