Whispered messages can be transmitted across a room directly into the ear they’re intended for, a shirt can change its properties whether it’s hot or cold out, and a new military grenade comes loaded with a net for capturing drones. All that and more in this week’s coolest scientific discoveries.
What is it? Valentine’s Day has just passed, but you can still whisper sweet nothings into the ear of your beloved. And now you don’t even have to be nearby to do it! Researchers at MIT have devised a way to use lasers to send quiet, targeted messages to someone from a few meters away.
Why does it matter? There are plenty of potential applications for such technology: for instance, to quietly warn of an active shooter, or simply communicate across a noisy room. The tech, described in Optics Letters, could also be used for spycraft or “super-targeted advertising,” according to MIT.
How does it work? Researchers devised two approaches to sending their acoustic whispers, both of which rely on the photoacoustic effect — their lasers take advantage of water vapor in the air to absorb light and form sound waves, a technique that works even in arid conditions. “There is almost always a little water in the air, especially around people,” said research leader Charles Wynn. “Our system can be used from some distance away to beam information directly to someone's ear. It is the first system that uses lasers that are fully safe for the eyes and skin to localize an audible signal to a particular person in any setting.”
What is it? Most youngsters learn about the magic of photosynthesis, whereby plants use sunlight to convert carbon dioxide and water into chemical energy. Fewer learn that the process is dogged by what scientists characterize as a “glitch,” called photorespiration, that hampers photosynthetic efficiency. From the human standpoint, that’s a bummer because reduced photosynthetic efficiency leads to reduced crop yields. But now researchers from the University of Illinois and the U.S. Department of Agriculture have figured out a way to engineer crops with a “photorespiratory shortcut” that increases their productivity by 40 percent.
Why does it matter? Published in Science, the study is part of the project Realizing Increased Photosynthetic Efficiency, or RIPE, funded in part by the Gates Foundation. RIPE’s goal is to increase worldwide crop yields, boost incomes and reduce food insecurity — to, according to its website, “usher in the next Green Revolution, enabling farmers to produce more in this century than in the history of mankind.” Principal investigator Donald Ort said, “We could feed up to 200 million additional people with the calories lost to photorespiration in the Midwestern U.S. each year. Reclaiming even a portion of these calories across the world would go a long way to meeting the 21st century’s rapidly expanding food demands.”
How does it work? At the heart of the problem is the fact that, during the photosynthesis process, a key plant protein sometimes takes in oxygen rather than carbon dioxide — which produces a compound that’s toxic to the plant and that the plant must then recycle through the tiresome, energy-expensive process of photorespiration. The RIPE scientists found a way to engineer plants to, essentially, shorten the photorespiratory process by changing its pathways, so the whole thing required less energy. RIPE director Stephen Long said, “Much like the Panama Canal was a feat of engineering that increased the efficiency of trade, these photorespiratory shortcuts are a feat of plant engineering that prove a unique means to greatly increase the efficiency of photosynthesis.”
What is it? Penn State University researchers created a simple drug cocktail that helps convert cells next to damaged neurons into functioning new neurons.
Why does it matter? “Neuronal loss is the leading cause of symptoms in patients with neural injury or neurodegenerative disorders,” according to the study, which was published in Stem Cell Reports. The drug cocktail could have use, then, in treating such conditions as Alzheimer’s, stroke or brain injury.
How does it work? “The biggest problem for brain repair is that neurons don’t regenerate after brain damage, because they don’t divide,” said Penn State biology professor Gong Chen, who led the research team. Chen’s team focused on glial cells, which surround and support neurons but which, with the application of the right molecules, can be converted into new neurons; the team tested “various numbers and combinations of molecules” before landing on an approach that effectively worked on the glial cells. “Glial cells, which gather around damaged brain tissue, can proliferate after brain injury,” Chen said. “I believe turning glial cells that are the neighbors of dead neurons into new neurons is the best way to restore lost neuronal functions.”
What is it? At the University of Maryland, researchers have created a fabric that regulates itself depending on the environment: If it’s cold out, the fabric traps heat to keep the wearer warm; if it’s hot out, the fabric opens up to let heat through.
Why does it matter? Though outdoors types like joggers and skiiers revel in all sorts of fancy thermal attire, nobody’s been able to produce a material that can change its own properties in response to the environment — until now. Chemistry professor Ray Baughman, who wasn’t involved in the study, said, “This pioneering work provides an exciting new switchable characteristic for comfort-adjusting clothing.” You could go from the mountains to the beach without having to change your shirt.
How does it work? The Maryland researchers, under the direction of YuHuang Wang, used synthetic materials to create a new yarn that they then coated with a conductive metal. As the university explained in a release, “Under hot, humid conditions, the strands of yarn compact and activate the coating, which changes the way the fabric interacts with infrared radiation. They refer to the action as ‘gating’ of infrared radiation, which acts as a tunable blind to transmit or block heat.” They described the gating technique at length in an article in Science.
What is it? Engineers from the U.S. Army have obtained a patent for a new 40-millimeter grenade that releases a net that can capture and take down drones.
Why does it matter? Too many pesky drones annoying your Central Park picnic? BAM: Not anymore! (Just kidding: Both drones and, presumably, grenade launchers are banned from Central Park.) A more judicious use for the grenades will be on the military battlefield, where drones are increasingly important players and where something like a conventional surface-to-air weapon might be — as TechLink puts it — “overkill.” A way to net drones could also find use in civilian spaces where unauthorized flying vehicles really oughtn’t be: Drones in the airspace caused recent delays at airports in New Jersey and London, for instance.
How does it work? When a sensor tells the grenade that it’s close, a small charge ejects a net that spreads out 6 to 9 meters from the target. The grenade works in standard M320 launchers.