Breakthroughs and trends in the world of technology
Long and tube shaped, the axolotl looks like a smiling fish with four legs. But the endangered Mexican amphibian possesses a rare trait: It can regenerate a nearly perfect replica of almost any body part it loses, including up to half its brain. That makes the axolotl a favorite of researchers seeking to advance human regenerative medicine. In a recent paper, a multiuniversity team of biologists reported assembling the most complete sequencing of axolotl DNA yet, reports the New York Times. It was a big project: The salamander’s genome is 10 times as large as a human’s. The researchers used a technique called linkage mapping, which posits that DNA sequences that are physically close to one another on a chromosome were likely inherited together. They then created hybrids by breeding purebred axolotls with tiger salamanders. Next, those hybrids were mated with pure axolotls, so the team could track patterns of gene inheritance across 48 of the second-generation hybrids. The data revealed which DNA sequences are unique to axolotls and where those genes are situated on the salamander’s 14 chromosomes. By figuring out the relationships between DNA sequences that regulate and control genes—which often are located on the same chromosome—researchers can begin to look for similar controls in other animals, including humans, one expert told the Times. The goal is to help scientists determine if there are predictable ways to help humans regrow lost body parts with the skill and ease of axolotls. – Thomas K. Grose
One of the holy grails of robotics is creating sentient, or self-aware, machines. Engineers at Columbia University have taken a major first step, creating an articulated robotic arm that learned it was a robot, without using simulators and models designed by humans. The team, led by mechanical engineering professor Hod Lipson, programmed the arm to have no prior knowledge of physics, motor dynamics, or geometry, according to engineering.com. As the robot moved randomly, it kept track of its actions. It then crunched that data in a deep-learning program to analyze its movements, leading it to realize it was a machine. After more than 30 hours of self-training, the robot’s self-image was very close to the actual physical machine, within around 4 centimeters, the website says. Eventually, the robot was able to pick up and move items to other locations on its own, and to write text with a marker. Essentially, the robot is like a human baby; it learns by doing, Lipson says. “We conjecture that this advantage may have been the evolutionary origin of self-awareness in humans,” he tells the Telegraph, a British newspaper. The machine’s ability to know itself is still crude compared with humans’, he adds, but “we believe this ability is on the path to machine self-awareness.” In its recent paper, his team notes that “self-awareness will lead to more resilient and adaptive systems, but also implies some loss of control.” – T. G.
©Robert Kwiatkowski, Columbia Engineering
Could headphones soon be obsolete? Though their project is still in proof-of-concept phase, researchers at MIT’s Lincoln Laboratory have figured out how to use laser beams to transmit music and voices to human ears. The technology relies on the photoacoustic effect, in which light waves convert to sound when they’re absorbed by a material—in this case, water vapor, Science News reports. The beam itself is harmless—its wavelengths and intensities won’t burn eyes or skin. But the sounds are audible anywhere along the beam, rather than targeted on one listener. So the researchers came up with another technique that uses a rotating mirror to sweep the beam in an arc. The farther away the mirror moves, the faster the spot of light swings, Science News explains, making the noise audible only at the point where the swinging beam hits the speed of sound. So far, the second method only produces buzzing noises within a limited range of several meters. But the researchers hope to improve the technique so it can carry clear audio sounds over longer distances. Future applications could include sending messages to people in noisy environments, much like a whispering gallery, or being able to listen to music and TV without earbuds. – T. G.
©Mit’s Lincoln Laboratory
Do Not Dispose
Grocery packaging generates the vast majority of plastic waste. But a new global program involving many leading brands aims to temper our throwaway culture by bringing back reusable containers, reports Bloomberg. Led by TerraCycle, a New Jersey recycling company, and announced at last month’s World Economic Forum, Loop includes 25 companies—among them Unilever, Procter & Gamble, and PepsiCo—that will offer some of their most popular products in reusable containers. Shoppers will either buy them in-store or online, paying a refundable deposit. TerraCycle says that Loop will reduce waste, even factoring in the energy needed to prepare the packages for reuse and transport them. Bloomberg says the environmental cost of producing the containers is recouped after three or four uses. Participating brands used their own product designers to come up with the long-lasting containers. Some, like Tropicana orange juice and Hellman’s mayonnaise, harkened back to the past and will use sturdy glass, while Häagen-Dazs and Nestlé will use a double-walled aluminum jar to keep their ice creams cold. While reusable packaging costs twice as much to manufacture, accounting rules will allow companies to depreciate wear-and-tear expenses. TerraCycle founder Tom Szaky, whose firm is investing $10 million in Loop, tells Bloomberg that the project has cross-generational appeal. “Baby boomers look at this nostalgically and say, ‘This is how we used to do it,’ while millennials say, ‘I’m sick of all this plastic waste.’ ” – T. G.
Bricks are the world’s favorite building blocks, but they need lots of energy to make. Meanwhile, sewage-treatment plants churn out vast quantities of sludge, a third of which—some 7 million to 8 million tons—ends up in landfills, giving off greenhouse gases. Abbas Mohajerani, a civil engineer at Australia’s Royal Melbourne Institute of Technology University, has a solution to both problems: hybrid bricks made from biowaste mixed with soil. While not as sturdy as regular bricks, they still meet industry standards. And Mohajerani assures they don’t smell like a sewer. His research determined that if 15 percent of all bricks contained biosolids, all the world’s leftover sludge would be eliminated, the New York Times reports. Because the organic material disintegrates in the furnace, bio-bricks take about half as much energy to fire as do normal bricks. The process also makes the bricks more porous and filled with gases, so they’re lighter as well as better insulators. To make biosolid-brick production sustainable, Mohajerani tells the Times, manufacturing ideally should occur near wastewater treatment plants. “Otherwise, I don’t think it is likely on a large scale in the near future.” – T. G.
Curb Your Enthusiasm
City streets are often chockablock with cars, trucks, and buses. One reason urban roads aren’t even more clogged is the high cost of parking. But research at the University of California–Santa Cruz finds that the advent of self-driving cars—which could be plying the roads in five years—will make things worse and “create havoc.” Using game theory and a micro-simulation model, Adam Millard-Ball, an associate professor of environmental studies and public transit, calculates it would cost drivers only around 50 cents an hour to let their autonomous vehicles crawl along empty until they were needed. Even his best-case scenario found that as few as 2,000 robotic cars in San Francisco could slow traffic to less than 2 mph. Cities may try to incentivize owners of autonomous vehicles to use cheap remote parking lots, but it’s unlikely those lots can charge less than 50 cents per hour. Would regulations that make it illegal for a driverless car to be on the road for more than, say, 10 minutes without a passenger solve the problem? Too much of a blunt instrument, argues Millard-Ball, noting that a car could be on a legitimate mission—such as driving en route to pick up its owner. His solution: congestion pricing. Cities like London now use tariffs to reduce traffic in their centers to help combat pollution. Though such charges annoy commuters, “no one owns an autonomous vehicle now, so there’s no constituency” to protest the fees, says Millard-Ball, who is urging local governments to institute congestion fees well before driverless cars become the norm. – T. G.
Tap the Brakes
Wait! Don’t quit reading this to update your status. A new study by researchers at New York and Stanford universities found that temporarily quitting Facebook for four weeks could have beneficial effects. Participants in their survey of 2,844 Facebook users reported spending more time offline and socializing more with family and friends. They also reported being less up-to-date on current events but feeling less politically polarized. In addition, a small but significant number of respondents claimed their lives were happier and more satisfying during their Facebook holiday. Respondents underscored some positive aspects of Facebook use as well, including keeping them connected to family and friends, providing them with entertainment, and making it easier to organize philanthropy and activism. One researcher told the Washington Post: “The most remarkable thing is that our results do not support a strong anti-Facebook narrative, nor do they support a strong pro-Facebook narrative.” The study also noted its own flaws. A longer break might have produced different responses, for instance, and its timing—right before last year’s midterm elections—resulted in participants who were mainly younger, better educated, and more liberal than the average Facebook user. The team next hopes to study whether getting news from social media is more or less polarizing than following events in mainstream media. – T. G.
A third of all crops rely on honeybees for pollination, but colonies around the world have been collapsing for more than a decade, The leading cause of death is the Varroa mite. Affected hives are easily treatable, but beekeepers often don’t catch the infestation in time because they rely on a crude gauge: counting the dead mites that fall on a board beneath a hive. Spotting the tiny parasites amid the debris is difficult, so Swiss beekeeper Alain Bugnon worked with students at the École Polytechnique Fédérale de Lausanne to develop a smartphone app that uses machine learning to do the job. All the beekeeper must do is upload photos of the boards to a Web platform hosted by the school. By scanning thousands of mite images into a computer, the students taught the app how to spot the parasites no matter how much other junk littered the plank—and spit out an answer within seconds, with a 90 percent success rate. Bugnon and the school are now working to get the app to as many Swiss beekeepers as possible. They also expect to compile their images in a nationwide database to produce up-to-the-minute statistics to help track Varroa infestations and potentially identify strains of bees that are resistant to the destructive mite. – T. G.
Greenhouse Gas Trap
Two big drawbacks of carbon sequestration technology—the capture of carbon dioxide from industrial smokestacks for safe burial—are its high cost and energy use. But chemists at the Department of Energy’s Oak Ridge National Laboratory, inspired by the technique used to remove CO₂ from SCUBA gear so that divers can rebreathe the carbon-rich air they exhale, have come up with a method to recover carbon using nearly a quarter less energy, according to Science. The researchers dissolved a class of organic chemicals called bis-imino guanidines, or BIGs, into water, breaking down the molecules into positively charged hydrogen protons and negatively charged hydroxide ions. The BIG molecules then bind with the free-floating protons. These ions react with the bicarbonate ions that form when CO₂ is added to the solution, resulting in crystals that can be removed and broken down so that the carbon can be collected while the BIGs get re-dissolved. Though the technology works well in the lab, the Oak Ridge team says it’s not ready for industrial use. Coal-fired power plants emitted more than 1.2 billion metric tons of carbon in the United States alone in 2017, so an awful lot of BIGs would be needed to scrub just one smokestack. On the plus side, the chemical is reusable and costs less than $1 per pound. – T. G.
©Neil J. Williams and Erick Holguin
Reinventing an Iconic Device
The stethoscope, one of medicine’s basic diagnostic tools, hasn’t changed much since its debut more than 200 years ago. And that’s a problem for health-care workers in the developing world, where noisy, poorly equipped clinics can make it hard to detect symptoms of pneumonia—a disease that kills nearly a million children worldwide each year. Two electrical and computer engineers at Johns Hopkins University have developed a smart stethoscope that’s not only inexpensive but also packed with software that makes it more effective and reliable. Writing in the IEEE Spectrum, Mounya Elhilali and James E. West explain how learning to properly position a stethoscope and then interpret what it picks up is “something of an art form” that even experts don’t always get right. The challenge is compounded when ambient noise masks the subtle sounds from a patient’s chest and there are no X-ray machines to confirm diagnosis. The pair worked with doctors and public-health experts to basically reinvent the stethoscope, loading it with smart technologies they say make it as accurate as an X-ray. Their digital device uses active acoustics for noise cancellation and artificial intelligence to help health workers make correct diagnoses. It also has arrays of transducers to pick up strong signals even if not placed properly on the chest. A prototype is now being field-tested in Peru, Bangladesh, and Malawi, and a start-up, Sonavi Labs, has been launched to market the smart scope. – T. G.
©Zebadiah Potler, Johns Hopkins University
Sometime in the future, scientists could use high-end microscopes to follow neuron synapses to figure out how our brains form and recall memories, or how we use emotions when making decisions. That could be the upshot of a new microscopy technology devised by a team of researchers led by Edward Boyden, an MIT professor of neurotechnology. In a recent experiment, his team was able to image layers of neurons in the somatosensory cortex of mice. The researchers zeroed in on pyramidal cells, neurons common to nervous systems. By monitoring proteins in the presynaptic and postsynaptic regions of the cells, they were able to compare the density of the cells’ connections in different parts of the cortex—analyzing millions of synapses in just a few day rather than the years it would take using current electron microscopy. Their achievement was the result of wedding two microscopy technologies. Boyden developed a way to obtain extremely high-resolution brain-tissue images in 2015 using an ordinary light microscope by first expanding the tissue before imaging it. He’s now merged that technology with a 3-D technique recently developed at the Howard Hughes Medical Institute called lattice light-sheet microscopy, which can image large samples rapidly. The combined technologies can image individual neurons at unprecedented resolution and speed. In another experiment, they used the technology to find differences in the numbers and arrangements of synaptic boutons, the sites where synapses occur, within a variety of animals’ olfactory circuits. The method could eventually be used to figure out how humans make memories or decisions. Beyond brain scans, Boyden’s lab is planning to study how HIV evades the immune system. Another application could be learning how cancer cells interact with healthy cells. – T. G.
©Ed Boyden group (MIT) and Eric Betzig group (HHMI Janelia Research Campus)
Back to the Future
Think steam power is so 19th century? Don’t be too sure. A project involving NASA, the University of Central Florida, and Honeybee Robotics in California has developed a prototype asteroid explorer propelled by steam. Called WINE, for the World Is Not Enough, it’s the first prototype to demonstrate it can mine water by heating the asteroid’s regolith, or soil, and then use the water to generate steam for a propulsion system, according to Discover magazine. Designed to work on smaller bodies in the asteroid belt that have water and low gravity, the explorer would generate enough power to hop several kilometers at a time. WINE’s steam propulsion is also powerful enough to reach escape velocity on a small asteroid, permitting exploration of other space rocks. Power for the first stop’s mining and steam-making activities would come from solar panels or, if the asteroid is too far from the sun, radioisotope heaters. – T. G.
Watts, Not Weapons
Thorium is a slightly radioactive element that’s much more common in nature and less toxic than uranium. Physicists have long seen it as a potentially more efficient alternative in nuclear power plants. On its own, however, thorium cannot perpetuate the same chain reaction as uranium, whose components release more neutrons that create more fission—which, if operators lose control of the process, can lead to a meltdown like those that occurred at Chernobyl and Fukushima. For thorium to generate a fission feedback loop, it must be mixed with a small amount of another, more powerful radioactive material, which is why there aren’t any thorium reactors. However, New Atlas, an online science publication, reports that scientists at Russia’s Tomsk Polytechnic University have designed a thorium reactor that also uses weapons-grade plutonium (plutonium-239), a nasty byproduct of uranium reactors. The result, they say, is a cleaner, more efficient reactor that also safely destroys 97 percent of the dangerously radioactive isotope, which remains toxic for more than 24,000 years. Beyond advancing nonproliferation, the TPU team says its thorium reactor has two other benefits: It’s 50 percent more efficient than typical reactors, and its waste heat can be used to desalinate water or produce hydrogen. – T. G.