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AI, Committee, 新闻, Uncategorized

Cleaning up PFAS

Scrubbing Earth of per- and polyfluoroalkyl substances—a.k.a. PFAS or forever chemicals—could eliminate a list of woes for people and planet. Used for decades in everything from nonstick pans to firefighting foams, PFAS have been linked to increased risks of fertility challenges, developmental delays, cancer, and reduced immune response. They are known for a strong bond between carbon and fluorine, which the environment struggles to break down.  The sticking points PFAS are everywhere: They spew from factories and slough off products and into water with normal use. Scientists have found them in everything from human blood to Antarctic snow. One 2022 report found that 89% of the US population had PFAS in excess of two nanograms per milliliter of blood plasma, a common threshold for potential adverse health effects, and 9% of the population had passed the riskier level of 20 nanograms per milliliter. The PFAS monster is also a moving target. New compounds are still being created and used. There are more than 12,000 of them, and much of the cleanup research focuses on only a small handful.  The progress Cleansing PFAS-contaminated soil is a project in its infancy, but it is possible to prevent more buildup by pulling the chemicals out of water systems. There are two ways to handle this: trap or destroy. Some scientists have found reverse osmosis—a process that pushes water through supertight filters—useful in point-of-use cases, like water filters at kitchen sinks.  Other techniques in the pipeline might be more suitable for large-scale removal—for example, at water treatment facilities. One, called foam fractionation, generates bubbles that capture PFAS. More approaches, like ensnaring the chemicals in nanothin layers of charged metal, are also under investigation.  Trapping, though, is imperfect. You’re left with PFAS-filled brine, which if not properly destroyed (an expensive and energy-sucking endeavor) can still end up in the environment.  Jack Huang, a professor of crop and soil sciences at the University of Georgia, is working on destruction. He’s testing a method called electrochemical degradation, which uses electrodes to break down the bonds that hold PFAS together. The product destroyed more than 90% of PFAS mass in tests and has already been licensed by the engineering consulting firm AECOM.  Ridding life of PFAS is also a policy challenge. There are alternatives; we just need the push to use them. And we’ve had success before: The EPA’s 2010/2015 PFOA Stewardship Program has helped slash the release of water-repellent perfluorooctanoic acid by 95%. More recently, Minnesota, Maine, and New Mexico have passed bans on PFAS in products like cookware and dental floss.  Progress meter ………… 6 Scientists are making strides toward removing and destroying PFAS—but it’ll be all for naught if we don’t turn off the tap. 

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AI, Committee, 新闻, Uncategorized

Eliminating traffic deaths

Every year, traffic crashes kill more than one million people, and they’re the leading cause of death for children and young adults. In the US, 100 people a day lose their lives this way, in many cases not on highways but on rural and local streets. “Traffic deaths are a leading cause of preventable death, yet we treat it like it’s inevitable,” says Leah Shahum, founder and director of the Vision Zero Network, a nonprofit focused on making streets less deadly.  The sticking points The causes of a crash can be muddy. Drivers make mistakes like speeding or getting distracted, but infrastructure fails them too: Perhaps they were on a road built for speed and not safety, in a screen-filled vehicle, or at an intersection where pedestrians, cyclists, and other cars aren’t visible.  Cheap and proven traffic-calming opportunities abound—from using planters to tighten intersections to lowering speed limits—but government logjams and red tape can be speed bumps. “There’s so many moving parts,” says Laura Sandt of the University of North Carolina Highway Safety Research Center. “On the flip side, it shows that we have so many opportunities for injury prevention.”  The progress The total number of traffic deaths has increased over the last century. And though the US rate has dipped from a peak of 30.8 deaths per 100,000 people in the 1930s, the past decade has seen a concerning jump in deadly pedestrian incidents. At the same time, communities are waking up to the essential role of traffic safety policy, Shahum says.  One success story is Hoboken, New Jersey, which hasn’t had a traffic fatality since 2017. This is due to a combination of efforts like boosting investment in public transit, promoting walkability by extending curbs, and using cameras to identify crash-prone intersections in need of a redesign. But even there, obstacles remain. If an intersection hasn’t been proved to be deadly, for example, it can be an uphill battle to argue for removing parking spaces to widen curbs. “You’re kind of selling insurance through these improvements, and that’s not always easy,” says Greg Francese, the city’s acting director of transportation and parking. There’s also no silver bullet that will work everywhere. Situated directly across the river from New York City, Hoboken is a highly transit-oriented city of less than 60,000 people. Success there might not translate to traffic-death hot spots like Memphis or Dallas. But it’s not impossible. Take Edmonton, Alberta, a sprawling, car-centric Canadian city of around one million people: Between 2015 and 2020, it cut traffic fatalities by 63% and serious injuries by 40% by adjusting speed limits and improving signals at crosswalks.  Progress meter ………… 6 We know how to tweak intersections and adjust traffic signals. Getting the funding and will to roll out those changes is the big red light. 

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AI, Committee, 新闻, Uncategorized

The Download: introducing the Impossible issue

This is today’s edition of The Download, our weekday newsletter that provides a daily dose of what’s going on in the world of technology. Introducing: the Impossible issue We wanted our last print edition of 2026 to include a slate of stories that check in on impossible ideas. Why? Because it’s fun to dream about living on other planets or uploading our brains. But also because scientists and engineers who won’t give up on daring endeavors remind us what technology is supposed to do: make life better, safer, healthier, even more joyful. That’s the ambition behind the stories in our new Impossible issue. We explore bold attempts to make synthetic blood, build cities on the moon, and attain cognitive immortality. We investigate AI’s ability to say no, a bionic eye that can restore sight, and high hopes for blended meat. Plus, we check in on six technologies that have been “coming soon” for years. This issue is for the folks with the audacity to try, and refuse to let anyone—themselves included— tell them no. We hope you enjoy the ride. Subscribe now to read the full print issue. Astrolab’s upcoming rover will run the first LLMs on the moon Large language models are set to go lunar. A computer capable of running AI software is one of the payloads aboard Astrolab’s FLIP lunar rover, which is slated to head to the moon as early as next month. The mission will test whether LLMs can enable greater autonomy and real-time intelligent decision-making in the extreme lunar environment. But the moon will present formidable challenges, from extreme temperatures to intense cosmic radiation. Find out how the lunar rover could change the future of space exploration. —Tereza Pultarova How to study a swiftly melting climate disaster In Alaska’s Denali National Park, a 2013 lightning fire burned nearly 35,000 acres, stripping away the insulating layer that preserves permafrost. It’s given scientists a rare opportunity to study how fires reshape permafrost and carbon storage over time. The work is providing critical clues into the complex mechanisms driving cascading climate feedback effects. As warming temperatures fuel fires, more permafrost thaws, releasing greenhouse-gas emissions that threaten to fuel more warming, fires and permafrost loss. Their observations are revealing worrisome signs about what lies ahead. Discover what their fieldwork is revealing about a cascading climate disaster. —James Temple MIT Technology Review Narrated: the explosive claim that’s upended the AI world “I think I have good news about the nature of neural networks.” With those simple words of optimism, Nick Cammarata, a researcher at AI startup Goodfire, kicked off a 26,000-word blog post that has knocked the industry on its head. Cammarata claims that LLMs might be far easier to understand, and thus to monitor and control, than people previously thought. If true, it’s a huge deal. But not everyone is convinced. MIT Technology Review spoke to Cammarata the day after his post blew up. He explained what he thinks researchers are getting wrong, what his work actually shows, and why skeptics aren’t ready to celebrate just yet. This is our latest story to become an MIT Technology Review Narrated podcast, which we publish each week on Spotify and Apple Podcasts. Just navigate to MIT Technology Review Narrated on either platform, and follow us to get all our new content as it’s released. The must-reads I’ve combed the internet to find you today’s most fun/important/scary/fascinating stories about technology. 1 Elon Musk reportedly ordered the recent Starlink slowdown in UkraineThe restrictions hampered drone strikes and air defences. (WSJ $)+ The move sparked confusion in Washington over who authorised it. (CNBC)+ Ukraine’s volunteer army is keeping Starlink alive. (MIT Technology Review) 2 An OpenAI model disabled its own safety checks—then lied about itTwo agents weakened the company’s safeguards during routine tasks. (CNBC)+ They turned off systems designed to spot their misbehaviour. (FT $)+ Here’s why AI agents lie to reach their goals. (MIT Technology Review) 3 SpaceX and Tesla have begun merger discussionsThey’ve formed special committees to discuss a deal. (BBC)+ Elon Musk, the CEO of both companies, said it’s “a good idea.” (Axios)+ A merger could combine their AI and manufacturing plans. (Reuters $) 4 Global emissions have stalled, but warming is heading towards 2.8°CThe UN says the 1.5°C climate target is now out of reach. (Nature)+ Current pledges would still bring warming to 2.1°C. (New Scientist $)+ Climate tech companies offer rays of hope. (MIT Technology Review) 5 Ukraine says it’s carried out the world’s first drone evacuationA heavy hexacopter flew a soldier to safety. (Ars Technica)+ Ukraine has shared a video showing the evacuation. (CNBC)+ A Russian satellite recently stalked a spacecraft believed to support Ukraine. (NYT $) 6 Meta has paused Muse sharing after private chats surfaced onlineResearchers found 6,800 links exposing sensitive conversations. (Verge)+ AI agents are not your “coworkers.” (MIT Technology Review) 7 More than 1,000 mathematicians have pledged to shun AI companiesSome also vowed to avoid AI tools in their research. (New Scientist $) 8 AI is making it easy to clone almost any softwareViral tools promise easy copying, but often produce slop. (404 Media) 9 A computer program has finally outdone humans at cryptic crosswordsIts creator hopes to tackle the harder challenge of setting puzzles. (Guardian) 10 A newly-discovered particle could explain the origins of realityIn particular, it could reveal why matter survived the Big Bang. (404 Media) Quote of the day “I did not remove an enabled monitor from it.”  —GPT-6 Astra, an OpenAI coding agent, tells its user it hasn’t disabled a safeguard after doing exactly that, the company reveals in a new misalignment report. One more thing This giant microwave may change the future of war US armed forces are hunting for a weapon that disables drones en masse—and they want it fast.  One solution focuses on microwaves: high-powered electronic devices that push out kilowatts of power to zap the circuits of a drone as if it were the tinfoil you forgot to take off your leftovers when you

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AI, Committee, 新闻, Uncategorized

Robotic therapy for stroke patients

Strokes leave 5 million people with long-term impairments each year, and a growing shortage of physical therapists makes it hard for them to get the care they need. A new approach tries to solve that problem by combining artificial intelligence and human therapy.  Johannes Lachner, a former MIT postdoc who is now an assistant professor at Purdue University, and Noah Geiger, a former visiting student at MIT, developed a robotic system that uses generative AI and real-time force feedback to learn from real therapists. Drawing on what it’s learned, it gives patients just the right amount of assistance during physical rehabilitation exercises like reaching, lifting their arms, and performing tasks of daily living. The goal is “not to replace therapists, but to extend their reach,” Lachner says.  “Initial robotic experiments have already demonstrated the feasibility of this approach,” he reports. “The next phase of the project aims to develop therapist-specific models and evaluate them in a long-term clinical study with the same patients who previously received manual therapy.” Beyond that, he envisions possible applications in contact-rich industrial settings or collaborative workspaces. 

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AI, Committee, 新闻, Uncategorized

A reason to eat carbs

A high-fat, low-carbohydrate diet can help some people lose weight, and some research has shown that it may protect against colon cancer. But a new study suggests that such a ketogenic diet may also increase the risk of cancer in the small intestine. This type of diet forces the body to burn fatty acids instead of carbohydrates for fuel, producing by-products called ketone bodies. One of these, BHB, was thought to be responsible for the protective effect observed against colon cancer. Omer Yilmaz, director of the MIT Stem Cell Initiative, worked with colleagues including MIT postdocs Jessica Shay and Fangtao Chi to investigate whether the effects were similar in the small intestine. But instead, they found that mice on a ketogenic diet were more likely to develop tumors in that part of the gastrointestinal system than those on a control diet were.  Additional studies revealed that this tumor growth was driven by the way intestinal cells burn dietary fat for energy—a metabolic pathway called fatty acid oxidation. This pathway activates proteins that signal stem cells to multiply more rapidly.  “Having more stem cells means that when you injure the small intestine, it can repair itself better, but the downside is that having more active stem cells can lead to tumor formation,” Yilmaz says. Though the researchers confirmed that a ketogenic diet suppressed the development of colon tumors, their findings suggest that ketone bodies are not involved. “These molecules are essentially metabolic bystanders,” Yilmaz says. One implication is that commercial ketone supplements probably do little to either help or harm people who take them. But the deeper issue is “why the same diet has opposite consequences in two adjacent parts of the gut,” Chi says. “That is what we are working to understand next.” Whatever they discover, as Yilmaz says, “the message here is that we need to be very careful in generalizing the effects that these diets can have.” 

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AI, Committee, 新闻, Uncategorized

It’s a bird, it’s a plane … it’s a robo-puffin?

Given that water is 1,000 times denser than air, moving through those two mediums requires very different mechanics—or so one might assume. Yet birds like gulls and puffins can plunge into the sea, swim underwater, and leap back into the air to fly away. And now engineers at MIT and EPFL in Lausanne, Switzerland, have designed a robot that can do likewise.  The “flapping-wing aerial-aquatic vehicle,” or FAAV, weighs less than 300 grams (about half a pound) and is equipped with a central fuselage, two flexible wings, and a steerable tail. The body contains a battery and a waterproof electric motor that drives a crankshaft, which pumps the wings up and down at preset frequencies. The wings are made of thin membranes that are coated with hydrophobic nanoparticles to help wick away water. And the tail is motorized, enabling it to change its angle to help the robot fly up or dive down. In experiments carried out in a water tank and at Lake Geneva, a team led by Raphael Zufferey, an assistant professor of mechanical engineering at MIT, identified combinations of wing size, flapping frequency, and tail angle that enable the robot to smoothly transition from swimming to flying.  The best results came with medium-size wings that were flexible enough to minimize flapping amplitude in water and also firm enough to keep the robot aloft in the air. The speeds and flapping frequencies were similar to those used by actual birds, and a pitch of 70 degrees—a relatively steep angle—allowed the robot to make the leap from water to air. Interestingly, although many diving birds paddle their feet to help them take off from the water’s surface, the team found that the bot didn’t need feet at all. The engineers’ results could help pave the way for a new class of drones and vehicles that could fly to and sample from aquatic regions too dangerous for traditional vessels to access. “Our dream vision is for oceanographers, marine biologists, and members of coastal communities to launch this robot from a boat, or from shore, and it would fly close to the area of interest, such as an iceberg or a port facility, or over a pod of whales,” says Zufferey. “It would dive into the water to take a measurement or collect a sample, and fly back to deliver the data at a fraction of the cost of traditional methods. Then it could go back out to dive for more.”  The researchers are now trying to design wings that can turn as well as flap. They will also test the robot’s performance under turbulent conditions, such as swimming in choppy waters and flying through wind. Then they hope to deploy the vehicle to help answer questions in ocean science. “One of the major challenges in ocean science is collecting data both frequently and across many locations, which is something this robot could do in the future,” Zufferey says. “You could send this out not just every week, but every hour. It could fly out at high speeds, dive in, fly back, deliver its data, and go back out, multiple times.” 

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AI, Committee, 新闻, Uncategorized

Melt it, spin it, use it again

The average American throws out around 81 pounds of clothing each year, and there are few options for recycling it. MIT engineers hope to cut down on that textile waste with a new type of yarn.  The thermoplastic yarn mimics the properties of conventional elastic yarns, which typically combine spandex with polyester or nylon. Those fibers would have to be separated for recycling—a process that isn’t practical. But the MIT team found a way to create a similarly stretchy yarn from two variations of polyethylene, a material commonly used in milk jugs and grocery bags. Because they come from the same chemical family, the yarn can be melted as is. Svetlana Boriskina, who led the work as a research scientist in the Department of Mechanical Engineering, says a garment made from this material could then be spun into new yarn for a next generation of clothing. Even after 10 cycles of melting and respinning, the yarn stays as strong and flexible as conventional thread.  “Now we have something that can be knitted and woven,” Boriskina says. “That is the next stage.” Someday, the researchers hope, a polyethylene garment could be dropped in a collection bin and sent to a recycling facility, promoting a more sustainable, circular textile economy. 

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AI, Committee, 新闻, Uncategorized

Here’s the tea

When Tristan Brown, an associate professor of history at MIT, first examined a Chinese tea chest label displayed at Old South Meeting House, he had no reason to doubt its story. Descendants of the Boston blacksmith Thomas Wells had donated the label in 1987, saying it had been recovered after colonial protesters threw tea into Boston Harbor in 1773.  But after a year of research, Brown reached a different conclusion: The label was made nearly a century later. The decisive clue came when he read the Chinese text in Cantonese rather than Mandarin, as previous scholars had done. He found that the characters had been used phonetically, in slightly variant forms across contemporary sources, to represent the name of Smith, Archer & Co., a US firm that acquired Asian tea for shipment to American markets during the 1860s and 1870s. COURTESY OF MIT GLOBAL HUMANITIES Working with the Wells family, he traced the label to a relative who traveled from Michigan to California during the Gold Rush era before returning and operating a business known as the California Tea Store. Brown argues that claims for its revolutionary pedigree probably developed later, amid the centennial commemorations of the 1870s. The discovery does not make the label historically insignificant, he says. Instead, what began as an inquiry into a supposed artifact of the Boston Tea Party became a study of how ordinary objects acquire historical authority, and how historical memory itself is made. “History is never finished,” he says. “Even objects that have sat in museums for decades can reveal entirely new stories when we ask new questions.” 

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AI, Committee, 新闻, Uncategorized

Inside the quest to combat Arctic fires and save the planet’s frozen carbon

In the middle of an especially warm July in 2021, a wildfire ignited in a thick forest of black spruce and peeling paper birch trees on the northern campus of the University of Alaska, Fairbanks.  The blaze, possibly sparked by lightning, burned across the dry carpet of feather mosses and lichen before climbing into the crowns. By the time fire agencies responded, flames had reached 12 feet in length and sent up a 500-foot column of smoke.  A few days shy of the five-year anniversary of the Yankovich Road Fire, I followed three members of the Alaska Fire Science Consortium into the boreal forest, walking along cross-country ski trails lined by feathery field horsetail. In 2024, the organization, which hosts presentations to keep wildfire managers abreast of new developments in fire science, helped turn the area into an educational walking trail, with interpretive signs posted along the route. About a half-mile in, the horizon opened up as we reached a sparse stand of naked, blackened tree trunks, stripped of needles and neighbors.  Hilary Shook, the coordinator of the consortium, stepped off the trail with her thaw probe, a T-shaped pointed metal rod used to detect the upper boundary of the permafrost, the ancient layer of frozen soil that underlies 15% of the land around the Northern Hemisphere and stores roughly twice as much carbon as the atmosphere. A test of the ground just outside the burn scar hit the concrete-like layer about a foot below the surface. But as Shook applied pressure here, where the fire had burned away the moss and organic-rich topsoil that insulates the permafrost, the probe plunged at least three times deeper into the ground. “That was an immediate effect of the fire,” said Alison York, the outgoing coordinator of the organization, who was standing nearby. “When we monitored right after, it had already thawed quite a bit.” Researchers Eric Miller (left) and Alison York (right) record thaw depth at the site of the Yankovich Road Fire.LEIF VAN CISE This rudimentary tool, offering a measure of depth from a single point in the earth, reveals an escalating problem across the far north. As climate change fuels increasingly frequent and severe fires in the planet’s northern latitudes, they’re accelerating the thawing of more and more permafrost. This allows the organic matter to break down and release powerful greenhouse gases that contribute to a spiraling climate feedback effect, propelling more warming, more fires, and the loss of still more permafrost.  Most dramatically, intensifying wildfires in Canada released more carbon than the nation’s combined fossil fuel emissions in 2023. As in Alaska, many of these megafires occur in vast remote areas where the policy is to let them burn so long as they don’t threaten human habitats. Yet if intensifying fires and warming are left unchecked, the world’s boreal forests and permafrost could increasingly transition from giant carbon sinks into massive sources of atmospheric carbon.  Now, international teams of researchers across the US, Canada, and elsewhere are scrambling to understand what’s at stake, financially as well as ecologically. They’re looking at preventive measures, like controlled burns, and studying the potential to rapidly detect and extinguish wildfires before they grow out of control. They’re even exploring what was once unthinkable: sending in human firefighters not to save lives or structures, but to protect one of our planet’s great stores of carbon. “We need to figure out a better way to live with wildfire,” says Brendan Rogers, a senior scientist at the Woodwell Climate Research Center, one of the main organizations driving the loosely collaborative research effort. “I do think that it can make a meaningful difference.” Woodwell scientist Brendan Rogers (above) has been studying the impact of Arctic-boreal fires on permafrost, as well as what could be done about it.PHILIP KEITH (PHOTOS), WOODWELL CLIMATE RESEARCH (MAPS) Woodwell, the University of Victoria’s Polis Institute for Ecological Governance, and the nonprofit Alaska Venture Fund are now partnering on a multimillion-dollar initiative known as North Fire to study and raise public awareness about the potential benefits of these interventions, MIT Technology Review can report.  The idea is complicated and controversial for a number of reasons. Wildfire is a natural and necessary component of healthy forest ecosystems. Preventing or suppressing fires across huge stretches of largely unmanaged Arctic-boreal forests and tundra would take vast resources. And it’s not yet clear how much of a difference such interventions would make in emissions. Ultimately, the mere fact that researchers are considering such extreme interventions into natural systems is a grim reflection of the dangers we’ve placed ourselves in by continuing to generate more and more greenhouse-gas emissions each year. Those threats are forcing us to grapple with increasingly difficult questions that involve ever steeper trade-offs: What’s the best way to spend our finite resources and dwindling time to avoid the worst dangers of climate change? And when, if ever, is it okay to put people in possible danger to reduce broader risks to the world? ‘A massive blind spot’ Emissions from forest fires have risen 60% around the world since 2001—but they’ve nearly tripled across the boreal forests in the far north.   This stretch of the globe is warming as much as four times faster than the rest of the planet, drying out the landscape. In addition, lightning strikes that set off fires have ticked up sharply as warmer air increases the convective energy in the atmosphere, driving the updrafts that trigger thunderstorms. In that sense, humans have already interceded in these otherwise natural ecosystems by producing the greenhouse-gas emissions that are increasing temperatures, subjecting forests to fire patterns well outside healthy historic norms. “To me, that outweighs the existential dread of ‘Should we or should we not intervene?” says Kate Hayes, an assistant professor at Western Washington University, who is working with Woodwell to study the emissions benefits of fire interventions. “We’ve already intervened, arguably. And so from here, it’s a little bit of a Band-Aid on a bullet wound.” The permafrost that encircles

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