MIT engineers create a system for building shape-changing smart devices

A new set of modular components allows users to create reconfigurable smart devices with electrical connections that keep working no matter which shape the structure forms.

This electrical modularity can enable engineers to design interactive devices that can sense which shape they have taken, without the need for external wires. For instance, the modular components, which the researchers call “bifur-circuits,” could be used to rapidly design and prototype adaptable smart devices, like assistive furniture that helps individuals change body positions while recovering from injuries or reconfigurable robotic grippers that remain electrically connected when they change shapes for different applications. 

Developed by MIT researchers, these 3D-printed building blocks, which are a type of structure known as a mechanical metamaterial, can be combined to form many more possible configurations than traditional metamaterial structures. 

In a study presenting the new system, the researchers demonstrated several interactive objects, including a chair that converts to a table with storage and can also flatten for stowing. The structure senses its configuration and sends corresponding messages to an electronic display. 

These new metamaterials could also be used to design antennas for communications and sensing that form new shapes to adjust their frequencies in changing environmental conditions, without bulky mechanical parts. 

“Metamaterials can make complex mechanical assemblies easy to manufacture just by using repeating units. Our work expands on this design space. If we think of mechanical metamaterials as building blocks, then our work is one way to take advantage of their geometry to embed intrinsic intelligence into hardware, which could open many possibilities,” says Marwa AlAlawi, a mechanical engineering graduate student and lead author of a paper on the devices.

AlAlawi is joined on the paper by co-senior authors Ticha Sethapakdi, an electrical engineering and computer science (EECS) graduate student at MIT; and Stefanie Mueller, an associate professor in MIT’s departments of EECS and Mechanical Engineering and leader of the Human-Computer Interaction Group at the Computer Science and Artificial Intelligence Lab (CSAIL). Their co-authors include others at MIT, the University of Tokyo, and the University of Michigan. The research will be presented at the ACM Symposium on User Interface Software and Technology.

Shape-changing interactive structures

Mechanical metamaterials are programmable, three-dimensional structures of repeating units that can form complex shapes due to their geometries. When squeezed, pushed, or pulled, metamaterials can bend or twist in precise ways. 

For instance, “auxetic” metamaterials get wider when stretched, instead of narrowing.

In prior work, the MIT researchers used auxetic metamaterials to build reconfigurable antennas that formed three shapes depending on how the structure was stretched. This allowed the antenna to dynamically adjust its frequency range without complex, moving parts.

Next, the team wanted to expand the number of antenna configurations but were limited because the auxetic metamaterials could only form three fixed states.

In this work they created “bifur-circuits,” which are auxetic metamaterials that can form many more shapes based on how the modular units are connected and rotated. 

The units are also designed to be electrically modular. Due to the way conductive material is integrated into the bifur-circuits, electrical connections throughout the structure are maintained no matter how the object is rotated, pressed, or twisted to form new shapes. 

To create interactive objects with many possible configurations, bifur-circuits leverage a property known as mechanical bifurcation. 

Mechanical bifurcation is a sudden change in how a mechanism behaves when a force exerted on it passes a tipping point. For instance, when you gently bend the ends of a plastic ruler, once that force reaches a critical threshold, the ruler buckles.

In bifur-circuits, this bifurcation occurs when connected blocks are rotated in certain ways around a pivot point. The property allows connected blocks to form more stable configurations than one block could on its own.

Adding more bifur-circuits to a structure exponentially increases the number of potential configurations.

“Bifurcation allow us to significantly expand on this reconfigurability space. Just adding one extra unit gives us so many more combinations out of the same structure,” says AlAlawi.

Connecting and rotating components activates a unique circuit between adjacent units. This interactivity allows the units to communicate with one another, enabling the structure to sense its configuration.   

One of the biggest challenges the researchers faced was incorporating a conductive material that was flexible enough to bend, but still offered enough efficiency in the flow of electricity.

“The conductive material was a constraint we had to work around in the design process, and it dictated how the sensing between blocks would happen,” AlAlawi says.

Once they perfected the design, the researchers tested the durability of reconfigurable structures by compressing them more than 10,000 times. The structures showed no degradation in electrical connectivity.

The researchers also developed a user-friendly construction and simulation tool to simplify the bifur-circuit design process. The software generates instructions for a multimaterial 3D printer, which can fabricate the reconfigurable objects in one pass.

They demonstrated the versatility of bifur-circuits by fabricating a chair that can sense its geometry when its shape is changed to a tea table, as well as a shape-shifting controller that will launch one of several video games based on its configuration.

Bifur-circuits could someday be used in applications like interactive rehabilitation tools, shape-changing grippers for modular soft robots, or reconfigurable shelters that could respond to changing environmental conditions after a natural disaster.

In the future, the researchers want to explore more applications for bifur-circuits. They also want to add more interactivity into the structures and investigate additional metamaterial shapes.

“Bifur-circuits are one step toward developing mechanical building blocks with integrated intelligence. It would be interesting to build on this work and come up with building blocks that allow us to create a structure with any form or shape we want, and which are structurally stable and can be actuated,” AlAlawi says. 

This work was funded, in part, by Japan’s Science and Technology Agency and the Bahrain Crown Prince International Scholarship Program.

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MIT student leaders: Q&A with McCormick Hall co-president Sydney Baller

A Colorado native who originally planned to attend college close to home, Sydney Baller decided to come to MIT for the strong academic community. She knew she had found a new home in McCormick Hall after attending its Campus Preview Weekend (CPW) events in 2023. 

McCormick Hall opened in 1963 as MIT’s first women’s residence — a move that provided women the first real opportunity to attend the Institute in significant numbers. To support continuity of the McCormick community through its first renovation in its 63-year existence, MIT has established a dedicated McCormick lounge in the Stratton Student Center (Building W20), funded efforts to maintain dorm traditions, and more.

Now a rising senior in mechanical engineering, Baller is a year-round athlete (basketball and outdoor track), crafting enthusiast, and co-president of McCormick’s student government. With construction underway to renovate the residence, Baller is taking time to help support future MIT women so they can have the same powerful residential experience she’s had.

McCormick is scheduled to open again in August 2028 — well after Baller graduates. In this interview, she describes her thoughts on the transition and how she is working to maintain a sense of community among the dorm’s residents and incoming first-year students while updates are ongoing.

Q: Why did you choose to live in McCormick? 

A: I was recruited to play basketball in college, and other schools were pressing me for a decision. MIT was like, “Well, you got in. It’s up to you what you want to do.”  

So I came to CPW to find out what the campus is like. I stayed in [co-ed] Baker with one of my teammates. It was weird for me. I could have probably adjusted to being in a living space with men, but I guess I just bristled at the concept. I grew up in a Christian household, so I was used to certain things. I shared a bathroom with my sister, not my brother. 

What really set it in stone was going to the other CPW events at McCormick. They were like — “We’re an all-women’s community. The dorm is quieter. Everyone’s super nice. We like to do crafts.” Then they showed us the craft room. A whole room dedicated to crafts? I was sold.

Q: How would you describe the community in McCormick?

A: On the day my dad helped me move in, we had three suitcases I brought from Denver. He and I sorted out my stuff, and then we went down to the laundry room. I thought I saw a big spider or something, and a girl who was standing there asked, “Are you talking about Despereaux?” I had never even talked to this girl before. Even this was a way to bond! 

There’s a lot to love. Our heads of house are amazing. After the last day of class every semester, they have a tea and churro study break. They make the churros themselves. So we just come down, drink tea, chat with our friends, and eat churros and little tea sandwiches. That’s very McCormick — a little break with some good chatting. 

The heads of house also run something called “karao-cake.” When I first heard about it, I was like — “I’ll go for the cake.” They have a karaoke machine with a bunch of microphones attached, and we all sing songs together. And if they pick a song we don’t like, we all yell “No!” Everyone's on the same page. It gives really good sisterhood vibes. 

Also, I personally loved our all-women’s gym. As someone who has been an athlete for many years, I can say: We had amazing equipment in there. I’d rather work out where I don’t have to fight for a rack. I can just go and lift and do my workout.

Overall, the McCormick community is what you make of it. You can choose to be invested and have a great time. You can also just choose for it to be the place you come back to every night. I was in the same room sophomore and junior year, and so were a lot of the girls around me. By the end of last year it was like that scene from the “Barbie” movie — when they’re all in their houses, and say “Good night, Barbie! Good night, Barbie!”

Q: How did you get involved in the renovation project? 

A: I originally joined house government to be the craft chair and athletic chair. Later, I decided to run for co-president because McCormick was my first home away from home. I had honestly planned to go to college close to home, or where my friends were going. The thought of going to another state and being on my own just seemed too out of the ordinary. When I came here, I knew one person. 

When MIT first told us the dorm was being renovated, I was pretty excited to see what they were going to do. They held all-dorm events, brought donuts, and asked us to come and talk about what we envisioned for renovation. I said I wanted the biggest craft room you can imagine, pianos in every corner, and to get rid of the study cubicles in the penthouse no one uses. We really got to dream, right? 

But then MIT announced a one-year delay in the renovation, and you have the emotions. McCormick was home — and then they say it’s going to get renovated, then they say it will be next year. When my friend and I decided to run to become co-presidents, the rest of the dorm really didn’t want to talk anymore. We started meeting with [the Division of] Student Life on Zoom, but it was hard to get resident engagement. I appreciate that we’re in the conversations. We get to hear the numbers before other people do, but that’s just information.

Q: What’s the role of house government while the residence is being renovated? 

A: We do things that keep the energy alive. McCormick is more than just a building. The housing office just told us more than 300 incoming students expressed interest in the McCormick community, even though the dorm is being renovated.

To bring momentum into the renovation, we held an end-of-semester party where we dropped nice crewnecks, got a food truck, and had popcorn, cotton candy, a DJ, games, face paint — all the stuff. We also enjoy dorm movie outings, which would be a great tradition to continue. When the Taylor Swift “Eras Tour” movie was in theaters, we all got to have the experience of going over on the T together, and then sitting together singing Taylor Swift songs. We also saw “Wicked” and “Wicked for Good.” We have chill events, too, like crochet, painting, and eating pastries. All of this is about being together. Even if we’re not sitting there having a conversation, we’re existing together. That feels like home.

I’m also trying to help people who are dealing with the transition. It can be hard. You can’t have our heads of house move with you, or the craft room. You can’t have the cute merch that one of our students designs. If someone who has been moved to Maseeh doesn’t know anyone else on their floor, they don't get to have that Barbie moment. But maybe McCormick is holding a study break where they can hang out — a throwback to the old days, where we can craft, or drink boba, or whatever. 

Q: Has the effort been worth it? 

A: It’s worth it to me because I get to keep the momentum going, but I won’t know for sure until the dorm is open again and a freshman checks into their room and experiences the community.

They took our feedback doing the donuts and stuff, and they put a lot of our ideas into the design, but now I’ve got to see the finished product. I know MIT has to balance a lot of things, so they’re not necessarily going to do everything just because we asked. 

Q: What are your goals for when the renovation’s finished? 

A: The building won’t reopen before I graduate, so I guess there’s two things.

When I graduate, I would hope to see a house government team that’s excited to continue the traditions. It’s different to be affiliated with a community than to be living in it. I would love to graduate and leave here knowing McCormick is in good hands and the momentum our generation started helped drive us through to reopening. 

And when the dorm reopens, I want to come back and get a tour. I would just love to see the excitement around being back in the dorm. I’ll buy my own plane ticket!

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AI helps design new materials that work in the real world

Today, anyone with a large enough artificial intelligence model can generate millions of new material designs in minutes. Unfortunately, that hasn’t led to a huge leap in the number of new materials being used to improve the performance of products like computer chips and rockets.

One reason for the translation gap is that current models don’t reliably factor in the chemical stability of the materials they generate, and unstable materials aren’t very useful in the real world. That forces industries to allocate huge computational budgets to screening out all the unstable materials they generate, in some cases leaving behind a tiny fraction of usable options.

Now, MIT researchers have developed a framework that can be applied at the beginning of the materials generation process to vastly improve the stability rate while achieving targeted material properties. It works by ensuring every design satisfies certain key rules of chemistry relating to the electrons around the materials’ atoms before the expensive generation step begins. The researchers call their approach “crystal generator with valence-constrained design, or CrysVCD.

In a paper published today in Nature Computational Science, the researchers show how CrysVCD allowed several commonly used material models to meet those valence shell rules more often, and used it to achieve high lattice-dynamics stability — a stringent stability test — in nearly 70 percent of computational material generations. They also showed the approach could support the creation of materials with specific desired properties, like high thermal conductivity or high dielectric constant, which is important for computer chips and data centers.

A hint of how the researchers envision people using their system is in the name.

“If material-generating models are like DVDs, we are like the DVD player,” says associate professor of nuclear science and engineering Mingda Li. “You can plug this into any kind of model, not only existing diffusion models but also future models, where people can’t generate enough stable materials, and it can improve stability.”

Joining Li on the paper are Mouyang Cheng SM ’26 and Weiliang Luo, MIT doctoral students in materials science and engineering and chemistry, respectively; Hao Tang PhD ’26, a recent graduate in materials science and engineering; Bowen Yu, a senior undergraduate in physics; Yongqiang Cheng, a staff scientist at the Oak Ridge National Laboratory; Weiwei Xie, an associate professor at Michigan State University; Ju Li, MIT’s Carl Richard Soderberg Professor in Power Engineering; and Heather Kulik, MIT’s Lammot du Pont Professor of Chemical Engineering.

More efficient materials

Computational approaches to materials design have been around for decades, but recent advances in artificial intelligence have increased excitement about their potential. Of particular interest are models that can start with a desired material property and work backward to deliver a material that achieves that goal.

Some of those models use an AI technique known as diffusion, which is commonly used to generate images, while others use large language models like the one powering ChatGPT and Claude, but both approaches struggle to ensure their material generations achieve chemical stability or follow fundamental principles about how chemicals interact and behave.

The solution has been to add another layer of computing on top of the generative process to filter out unstable materials.

“It’s becoming easy to generate the material structure,” Cheng says. “But the validation process, especially the part where you test the stability, has a huge computational cost. It’s something like 90 percent of the computational cost for creating usable materials, and it can take weeks or months.”

Big companies with huge computing budgets can afford to run those processes, but many small companies and research labs can’t, potentially limiting innovation in the field.

“In academia, where we have fewer resources, I think we can still achieve strong performance with smarter designs and other approaches,” Kulik explains. “Generating a model and then down-selecting for stability is inefficient. There’s a high computational cost. But if we put a language model in the beginning of the process to constrain the generation, you can significantly enhance the ratio of stable materials generated.”

The new study involved MIT researchers affiliated with the departments of Materials Science and Engineering, Chemistry, Chemical Engineering, Physics, and Nuclear Science and Engineering. Together the researchers combined AI diffusion models with a language model. In the first stage of their process, the language model produces chemically valid formulas. In the second stage, the diffusion model uses that formula to generate the corresponding atomic structure of the crystal material in coordination with the underlying material generation model.

“Diffusion for typical material generation is a slow process — you can think of it like 1,000 steps to create one material,” Luo says.

“In contrast, when our model is used in the beginning, you can think of it like five steps. It allows you to screen out the unstable materials to generate higher quality materials. And it works with any models generating materials,” Tang adds.

The researchers showed their approach created more stable materials an order of magnitude more efficiently than approaches that rely on screening materials after they’re generated. When fine-tuned on stability metrics, their approach produced crystalline materials that achieved 68 percent mechanical stability and 85 percent metastability, which measures if a material stays in a stable state when undisturbed.

The researchers then used their approach to generate material candidates with high thermal conductivity and easy polarization in an electric field.

“These are materials useful for the semiconductor industry and high thermal conductivity materials relevant to data center cooling,” Ju Li says. “In principle, you could also use this to create other properties, but thermal conductivity has become really important for cooling data centers. There’s been a huge increase in energy use in that industry, and 30 percent of that energy goes to cooling. The industry needs materials with high thermal conductivity to more efficiently remove the heat.”

Democratizing material design

The new approach doesn’t work with every kind of material — it works best with solid structures with highly ordered internal arrangements. Still, the approach could be used to generate stable new crystalline materials with a host of important properties.

“We are not just generating stable materials, we’re also prioritizing performance,” Cheng says. “Any time you have two goals, achieving those goals with anything over 50 percent is hard in this field. In the past, people might have a goal for specific properties and not stability, or vice-versa, and get a single-digit percentage of materials that fit their goal.”

Ultimately the approach will enable more researchers to develop novel materials for a range of next-generation applications.

“This will save huge computation costs and time by removing downstream selection requirements,” Li says. “That will help not only large efforts that generate hundreds of millions of materials, but also smaller research groups with targeted applications.”

The work was supported, in part, by the U.S. Department of Energy, a Mathworks Engineering Fellowship, the National Science Foundation, and the U.S. Defense Threat Reduction Agency.

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Retooling to help democracy revive

In the 20th century, the United States built the world’s dominant manufacturing powerhouse. A thriving middle class grew, well into the 1970s. The U.S. was a beacon of democracy, defeating fascism in World War II and beating back communism and other forms of authoritarianism during the Cold War. 

To MIT economist Daron Acemoglu, there is a deep intertwining among these things. Democracy, his work has shown, helps economies grow. As the industrial economy expanded, in Britain, the U.S., and other countries in the 19th and 20th centuries, so did democratic participation, as people tried to stake out new rights, or make real the rights ascribed to them. 

“The industrial age created the tools for shared prosperity around which democracy organized,” says Acemoglu, a Nobel Prize-winning economist and Institute Professor at MIT. 

Today, though, income inequality has grown markedly in the U.S., starting around 1980. The U.S. has deindustrialized to a significant extent, offshoring production and hurting shop-floor workers and their families. As Acemoglu sees it, this economic realignment has had deep civic consequences: A stranded working class has become more alienated from the institutions and ideas traditionally buttressing democracy.

And for those around the world supporting democracy, he says, “You really need to have the working classes in your coalition for it to make any sense.”

Acemoglu explores these topics in a new book, “What Happened to Liberal Democracy? Remaking a Politics of Shared Prosperity,” published by Penguin Random House. In it, he looks broadly at the benefits of democracy, the tensions it faces in everyday life, and democracy’s trajectory in recent decades.

Broadly, Acemoglu favors rebuilding “working-class liberalism,” essentially seeking the largest coalition that favors self-government and the rule of law. “Working-class liberalism has strong communal roots, eschews social engineering, and prioritizes shared prosperity, jobs, and public services,” Acemoglu writes in the book.

After all, Acemoglu believes, democracy is the one form of rule that promotes rights and liberties, and allows the flexibility and “experimentation” we need to address all the challenges a complicated world throws at us.

“Democracy is the only way we can make progress in society,” Acemoglu says. “Trying to impose top-down solutions to all our problems will ultimately not work.” 

Along the narrow corridor

Acemoglu has long studied the relationship between economic growth, rights, and democracy. With economist Simon Johnson of MIT and political scientist James Robinson, now of the University of Chicago, Acemoglu published a landmark series of studies in the early 2000s demonstrating that economic growth is helped by the development of stable democratic institutions, including property rights. For that work, Acemoglu, Johnson, and Robinson later shared the 2024 Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel. 

Acemoglu’s 2012 bestseller “Why Nations Fail”— written before democracy’s current challenges seemed as acute — synthesized his research on these topics. His 2019 book “The Narrow Corridor,” co-authored with Robinson, casts democratic governments as essential to liberty because they protect people simultaneously from overreach by an authoritarian state, on the one hand, and from domination by other groups in society, on the other. 

However, as Acemoglu has consistently emphasized, self-governance is an ongoing effort; this machine does not run on its own. Relatedly, in the new book, Acemoglu critiques some famous attempts to formulate governance as a neat “social contract,” including Jean-Jacques Rousseau’s conception of a “general will” in society. 

Those ideas helped make the case for political rights, but actual governance in a pluralistic society will always be a messy process. 

“You have to allow communities, and societies in aggregate, to build rules around shared values for anything to stick as institutions, norms, or aspirations,” Acemoglu says. “When you go down the social contractarian path, you sometimes fool yourself into thinking there are clear solutions to dilemmas that in reality don’t quite have such obvious ways of being resolved.” 

For instance, Acemoglu notes, democracy itself “is built on tolerance and acceptance of plural perspectives, but how do you deal with people who are intolerant?” In the book, he largely regards interventions to stamp out seemingly intolerant thought as being unwise and politically counterproductive.

“You’re not going to have a clear-cut solution to all cases,” he says.

The economic realignment

Even with leaders backing a pragmatic, flexible approach to self-governance, democracy faces another challenge: supporting the material welfare of citizens. And here, “What Happened to Liberal Democracy?” takes an unflinching look at the postwar economy, finding fault lines that have shaken the political order. 

The roughly three decades after World War II were fantastic for many workers in democracies, and certainly in the U.S., where middle-class incomes grew by 2.5 percent annually into the 1970s. 

There were always going to be forces pushing back on this trend, and U.S. companies started offshoring and outsourcing production work to clamp down on wage growth. But one other technological and economic trend occurred just as the middle classes of the industrial economy were reaching new heights. 

“Then computers happened,” writes Acemoglu in the book — referring to a complex set of economic and civic realignments involving technology-driven shifts in work. 

Over time, computers started replacing significant numbers of clerical office workers, shop-floor industrial workers, and other types of employees who were earning middle-class wages without holding a college degree. In recent decades, middle-class incomes have only grown by about 0.5 percent annually. 

To be sure, computers have produced plenty of benefits, and created many new forms of work. But as research shows, those jobs have tended to go mostly to college-educated employees, creating a significant split in society between well-educated, well-paid, white-collar workers, and less-educated, worse-paid workers in blue-collar and service jobs. That national share of income hauled in by the top 1 percent of earners has basically doubled in this time, from 10 percent to nearly 20 percent.

Crucially, in Acemoglu’s analysis, this material gap between more-educated and less-educated social cohorts has translated to U.S. politics, with political groupings reshuffling along educational lines, and cultural politics following suit. That’s the dynamic the U.S. faces now — even as one also accounts for the effects of social media and other polarizing features of contemporary society. 

“We now live in a less-industrial world, and we also live in an age defined by social media, much greater levels of conflict, more polarization, and now AI, and all of that complicates things,” Acemoglu says. 

Always a work in progress

This precise feature of contemporary society — deindustrialization fueling an earnings gap that has led to more political polarization — is what shapes Acemoglu’s prescription in response, the idea that “working-class liberalism” is needed to strengthen democracy. 

There are many potential ingredients in this formula, from politicians determined to reach across class lines to workers regaining the impetus to organize in their workplaces. 

“Trade union participation itself is a very important form of local governance that’s very difficult or unimaginable in an authoritarian society,” Acemoglu says, even while noting that he has not always agreed with the actions of particular unions in the past. 

Still, Acemoglu adds, “I don’t think the economic aspect is the only one, in that you cannot just gain the trust of workers by ensuring there are wage gains. That is an important step but it is not sufficient.” Voters need asurances that politicians are thinking about them, at least share their concerns, and have a grounding in similar values. More candidates today need to seek a shared language about those things.

That’s not easy in a world characterized, in part, by global migrations, increasingly diverse national populations, and economic flux. But it is possible, Acemoglu thinks. 

“There are deep dilemmas faced by liberal democracy that were sometimes going to come to boiling points, and this becomes more heightened when societies such as the U.S. and some European ones are simultaneously becoming more complex, more globalized, and more hetereogeneous,” Acemoglu says. On the other hand, he adds, “Multiracial tensions, I would say, were much worse for the U.S. in the 1950s and 1960s. We made democracy work then, in the face of much more difficult race problems, so why not today?”

None of this is a straightforward task, of course. “Forging working-class liberalism is a tall order in the best of times and much more challenging in today’s polarized environment,” Acemoglu writes in the new book. Still, he adds, even in frustrating moments, the stakes are too important for people to relent.

“Democracy is a success,” Acemoglu says. “It’s easy to fall into a trap of painting the democratic project as being doomed to failure, and I want to avoid that.” He adds: “It continues to be a work in progress.” 

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Cells use a little-known molecule to protect themselves from iron overload

Iron is essential. Our cells need it to produce energy, carry oxygen throughout the body, and power countless chemical reactions that sustain life. But this metal has a dark side. When too much of it is left free inside cells, it can trigger destructive reactions that break down DNA, proteins, and even cell membranes.

Now, MIT associate professor of biology and Whitehead Institute for Biomedical Research member Ankur Jain; MIT assistant professor of biology and Koch Institute for Integrative Cancer Research member Whitney Henry; and Pushkal Sharma PhD '26 have discovered that cells rely on an unexpected protector against this threat: small molecules called polyamines.

The researchers’ detailed findings, published Aug. 14 in the journal Cell, reveal that polyamines act like storage lockers for iron, safely holding the metal in a non-reactive state until cells need it.

These findings solve a decades-old mystery about why cells maintain such extraordinarily high levels of polyamines and uncover a previously unknown defense mechanism that protects cells from toxic iron overload.

This work could also help scientists develop better cancer treatments, by allowing iron overload to trigger cancer cell death. It could also offer new clues about diseases like early-onset Parkinson’s disease, in which mutations affect polyamine levels within neurons.

The Jain Lab studies RNA, the intermediary between DNA and the tiny molecular machines called proteins that perform most of the essential tasks inside cells. The lab is particularly interested in how RNA folds, misfolds, and sometimes clumps inside cells.

Jain and Sharma first began studying polyamines because these molecules bind to RNA and help shape its structure. However, they suspected that polyamines must be playing other roles inside cells: they’re among the most abundant small molecules within cells, present at levels comparable to ATP, the molecule cells use as their energy currency.

“We’ve known that without polyamines, cells stop growing and dividing,” Jain says. “But their best-known function only requires a small fraction of the polyamine levels cells actually have.”

To uncover polyamines’ hidden function inside cells, the researchers used a large-scale genetic approach that allows them to screen the entire genome at once, rather than testing genes one-by-one, in order to find out which cellular processes are impacted when polyamine levels are changed within cells.

The screen revealed that when cells have reduced levels of polyamines, a protein called GPX4 becomes essential for survival. GPX4 is known to prevent harmful chemical reactions that damage the fatty molecules that make up cell membranes. 

The team also found that cells with lower polyamine levels have higher amounts of another protein that acts as an iron sponge and keeps the metal in a mineralized form. Together, these findings led the researchers to hypothesize that polyamines might be helping keep iron in a safe, non-reactive state within cells.

To test this idea, they developed a new fluorescent sensor that would allow them to measure chemically reactive iron inside living cells. The new sensor causes living cells to glow based on the amount of chemically reactive iron they contain, allowing researchers to track any changes under a microscope in real-time.

The team paired the new iron sensor with another sensor they had previously developed that measures polyamine levels within cells. By employing them simultaneously, they observed a striking pattern: As polyamine levels dropped within cells, the amount of chemically reactive iron went up, offering new evidence that polyamines play a key role in preventing toxic iron build up inside cells.

Beyond answering a fundamental biological question, these findings could have implications for cancer treatment. Cancer cells often rely on high polyamine levels to support their rapid growth and division. However, cancer drugs designed to lower polyamine levels to stop cell division have had limited success.

“We saw that when polyamine levels fall, cells rely on GPX4 to protect themselves from iron toxicity,” says Sharma, who is also the first author of the study. “This could mean that combining drugs that lower polyamine levels with those that block GPX4 might be more effective for killing cancer cells than targeting either pathway alone.”

The discovery may also have implications beyond cancer. Mutations in genes that help move polyamines around cells are linked to a rare form of early-onset Parkinson’s disease, and scientists have long observed unusually high levels of iron in the brains of Parkinson’s patients. 

While it is still unclear whether excess iron directly contributes to neuron death in Parkinson’s, the discovery that polyamines help buffer reactive iron inside cells offers a possible explanation for this link and opens new directions for future investigation.

In addition, the researchers expect the new iron sensor to be a valuable tool for other scientists. By allowing them to track chemically reactive iron inside living cells, it could power new discoveries in aging, cancer, and neurodegeneration.

“There are a lot of promising future directions for this work,” Jain says. “It’s exciting to think about how these tools and findings could help answer further questions about disease pathways and potentially help design better therapies.”

This work is supported by grants from the National Institutes of Health, Bumpus Foundation, and Pew Charitable Trusts. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

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A new kind of aircraft departs an MIT classroom and arrives at an Ohio factory

A former MIT class project is becoming an $850 million effort to manufacture a new kind of aircraft in Ohio.

Electra began as an idea for a hybrid plane that could take off from shorter runways than traditional airplanes but have more range and speed than all-electric aircraft. Now, like other great MIT projects, it’s making an impact far beyond campus.

The company’s fixed-wing aircraft is designed to make travel easier, especially for people who don’t live in the immediate vicinity of a major airport. The plane features a smaller, more efficient engine than traditional planes, along with batteries to give it added power during takeoffs and landings.

With a range of around 1,200 miles and a cruising speed of around 200 miles per hour, the plane could improve the travel experience for many kinds of trips while cutting down on fuel use. And, given the much shorter runway needs and quieter operation than traditional planes, the plane can leverage unique access points such as barges, parking lots, and soccer fields to take off and land instead of traditional airports. 

“Helping people travel between 50 and 250 miles is the sweet spot for this technology,” says Electra Director of Technology Development Chris Courtin SM ’19, PhD ’24. “This can be a better option than driving or commercial airlines for many kinds of trips. There’s a lot of people traveling in that range and a huge amount of friction in existing ground and air transport systems. This could be a big benefit to those people.”

Courtin has worked on the hybrid plane concept since its inception, first as part of a class project at MIT, then as a teacher’s assistant, and finally as part of his PhD thesis. The company was founded by another alumnus, John Langford ’79, SM ’83, SM ’85, PhD ’87, and counts two MIT professors — Mark Drela and John Hansman — as its founding technical advisors.

“The company has really benefited from a strong collaboration with MIT,” Courtin says. “One of the compelling things about MIT is it gives people space to marry the theoretical side with the practical side — to actually go build the airplane and see if people will buy it.”

Electra has already built and flown a two-seated version of its plane. Last month, the company announced an $850 million investment to scale production of its nine-passenger aircraft in Springfield and Clark County, Ohio. The investment, which is expected to create 1,975 new jobs, means Electra will be building the next chapter of aviation in the state where engine-powered human flight first began.

From concept to company

The origins of Electra date back to a 2017 project among graduate students in MIT class 16.886 (Air Transportation Systems Architecting). Electric vertical takeoff and landing (eVTOL) aircraft were garnering excitement at the time, and Courtin’s group wanted to compare that approach to alternative designs.

“It was an open-ended, project-based class where you look at developments in aerospace,” Courtin says. “My group realized short takeoff and landing aircraft had a lot of advantages over eVTOL for getting people where they wanted to go. We started exploring using the same technology — lightweight, electric motors suitable for aviation — to make a new aircraft, which we now call the ultra-short takeoff and landing aircraft.”

The idea was to use batteries and small electric motors to shorten the runway and landing space of a fixed-wing aircraft while leveraging blown wind to travel farther distances in the sky than would be possible with electric motors alone.

The concept was developed further in several senior design classes co-taught by Drela and Hansman, while Courtin served as a teacher’s assistant. In the classes, student collaborators built a subscale model of the aircraft to prove it would work, testing it in MIT’s Wright Brothers Wind Tunnel and in flight. Courtin went on to work on parts of the concept for his PhD. 

In 2019, John Langford, who had been running the aircraft company Aurora Flight Sciences, which had recently been acquired by Boeing, got involved. Electra was officially formed that year.

As a first step, Electra’s team built the EL2, a two-seated version of its aircraft. That included designing and testing the hybrid propulsion system. The EL2 completed its first test flights in 2023 and has since completed over 200 flights.

The aircraft has a gas-powered generator located in its nose and two batteries under the floor, both of which feed the propellers during takeoff and landing. When cruising, the aircraft uses the generator, which can also charge the batteries.

“The gas generator is like a traditional turbine engine used in a conventional aircraft, only instead of driving a propeller or fan it drives an electric generator,” Courtin explains. “That feeds power to the eight motors on the wing. It allows you to have a smaller and more efficient engine because you can size it for cruising, not takeoff and landing conditions.”

The eight motors create a blown lift effect that allows the aircraft to take off and land in areas about the length of a soccer field, much shorter than the runways for conventional airplanes.

For travelers, “the big benefit is you can save a lot of time,” Courtin says. “You don’t need to go to an airport, and you don’t have to go to a train station.”

Operators could also maximize existing infrastructure at airports:

“If you’re three hours away from the nearest major airport, there’s a lot of friction in that,” Courtin says. “With Electra, we could fly you to the nearest major airport, and you don’t need to use a runway, so it doesn’t add to congestion at these very low-capacity places.”

Electra’s aircraft are also more affordable than traditional aircraft and far more quiet.

“The large number of propellers means you can make them much quieter than if you only had one or two,” Courtin explains. “That’s important because helicopters are restricted from operating in places they otherwise could because of the noise.”

Scaling up

Construction on Electra’s 96-acre Ohio manufacturing facility will begin next year. The facility’s initial phase will be capable of producing 400 of its nine-seat aircraft each year. The next phase will expand capacity to around 800 aircraft per year.

Electra’s team could see their aircraft shuttling people to major airports for longer trips or ultimately eliminating the need for conventional airports entirely.

“If you don’t have an existing airport, that’s a very difficult thing to build these days,” Courtin says. “But finding a soccer field-sized area is not hard, especially with our noise reductions.”

Electra’s team is also exploring applications around military logistics, cargo transport, and humanitarian missions.

For the passenger aircraft application, Electra’s team believes that as it scales production, it will be able to make the passenger aircraft accessible to a broad swath of travelers.

“If we can keep the fixed-wing design simplicity and make this large enough, then the per-seat cost could get to a range where a lot of people would have access to this,” Courtin says. “It wouldn’t just be a luxury product, so it could help a lot of people.”

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The secret love life of the longfin squid

Squid have occupied New England’s maritime imagination for centuries, from fishermen’s tales of strange tentacled creatures to the widely publicized giant squid reports along North Atlantic coastlines in the 1800s. Today, we turn a curious eye toward the longfin inshore squid (Doryteuthis pealeii) — the “Boston squid” — which has long been an important part of regional commercial fisheries. These squid thrive in the emerald green depths off the coast of Massachusetts, where low visibility is characteristic of the turbid, nutrient-rich waters.

Keith Ellenbogen, MIT Sea Grant resident artist and acclaimed underwater photographer, knows these waters well. On a good day, he might have 20 feet of visibility beneath the surface. But even with the clearest conditions, these swift squid evaded Ellenbogen’s lens for months. 

In 2023, over 2.85 million pounds of longfin squid — likely over 6 million individual squid — were landed commercially in Massachusetts, with a value exceeding $2.82 million. Consistently among the top 10 species landed commercially in Massachusetts, the longfin squid shares the ranks with the iconic American lobster, Atlantic surf clam, and sea scallop, underscoring its enduring significance in the state’s seafood industry. 

In 2024, landings came in under 750,000 pounds, roughly a quarter of the previous year’s catch. Likewise, the spring 2024 trawl survey documented in the Massachusetts Division of Marine Fisheries Annual Report recorded a historic low in longfin squid biomass, following a record high in 2023. 

But this drop, while significant, doesn’t necessarily spell trouble for the species. Longfin squid often show large fluctuations in abundance from year to year. Their short lifespan of about six to nine months, combined with their sensitivity to shifting ocean conditions, makes their population dynamics inherently unpredictable. 

Kimberly Hyde, a biological oceanographer with the National Oceanic and Atmospheric Administration (NOAA)’s Northeast Fisheries Science Center (NEFSC), notes that NEFSC research scientists have expanded squid research over the past few years, including a two-year study on longfin squid to better understand their life history and track their maturity and readiness to spawn. Across the Northeast, scientists are also collaborating with the fishing industry through efforts including the Longfin Squid Biological Sampling Program (SQUIBS), Collaborative SQUid Size Monitoring (SQUISM), and the Squid-Squad, a highly interdisciplinary team of scientists, industry members, and managers with a common goal to improve squid science. Still, much of this cephalopod’s story remains hidden from sight. 

After years of trying to find and photograph a squid spawning aggregation, Ellenbogen chartered a vessel and worked with a network of local fishermen to locate concentrations of squid beneath the surface. In New England’s emerald-green, nutrient-rich coastal waters, visibility was limited, and although he knew he was directly above the spawning grounds, finding a cluster of eggs and squid 30 to 40 feet below the surface was far from easy.

“As I descended through the emerald-green waters of Cape Cod, I couldn’t see anything at first,” Ellenbogen recalls. “I knew I was in the right area, but the seafloor seemed empty. Then I noticed a few faint shadows moving in the distance.” 

As he swam closer, the scene slowly revealed itself. 

“First came the squid, then the egg masses, and then hundreds more animals appearing out of the green water. Suddenly I found myself surrounded by squid flashing colors, courting, competing, and spawning,” Ellenbogen says. “It felt like being in a theater, watching a carefully choreographed performance unfold all around me.”

Dozens of squid hovered intently in a circle with arms and tentacles stretching toward the focus of attention: a large pale cluster of eggs fixed to a bed of slipper shells and fingerlike seaweed. Thousands of gelatinous, translucent egg capsules swayed softly in the current. Male and female pairs broke from the outer circle with ceremonial precision, darting inward to spawn. Their alienlike bodies pulsed and flickered with waves of color, from flares of rust-red, golden yellow, and iridescent pink to flashes of lightning white. Their brief lives had culminated here in this critical moment of coordination to give rise to the next generation. 

Longfin squid live fast and die young, exhibiting incredible exponential growth throughout their lifespan of less than one year. They emerge from egg capsules as planktonic hatchlings — paralarvae — that already look like tiny 1.5 millimeter simplified versions of their adult form. 

Still small but fast-growing, juveniles feast on planktonic prey in coastal, surface waters and move deeper in the water column as they grow larger, settling on a life closer to the seafloor. As natural-born ambush and pursuit predators, they begin hunting small crustaceans and other invertebrates — including other squid — with jet propulsion and 10 grasping arms and tentacles.

Like octopuses, squid have chromatophore organs, pigmented cells controlled by nerves and muscles through their central nervous system. Contraction or dilation of these sacs results in mesmerizing iridescence and color shifts. Their color-changing behavior serves several purposes, including camouflage, courtship, and communication through ancient visual language. And to add an extra layer of curiosity, squid themselves are effectively colorblind. Their eyes are well-adapted to detect contrast, brightness, movement, and even polarization, but not to perceive hues like we do.

According to a report from the NEFSC, longfin squid can reach sexual maturity at a mantle length of just 8 centimeters. Nearing adulthood, they migrate offshore to overwinter in deeper, warmer waters along the continental shelf. At night, they form large schools grouped by body size and move upward in the water column to feed. Growth remains rapid and temperature-dependent, with males growing faster and larger than females.

Longfin squid spawn year-round with seasonal and geographic peaks. In New England waters, spawning has been reported from May to August. Egg clusters, or mops, like the one Ellenbogen photographed, act like a hub. As reported by NOAA Fisheries, female squid lay fertilized egg capsules that contain about 150 to 200 eggs each in clusters attached to the ocean bottom. They return repeatedly to deposit multiple clutches of eggs over several weeks, with a typical female laying a total of 3,000 to 6,000 eggs.

Spawning typically occurs in seasonal pulses tied to water temperature and other conditions, sometimes triggering large spawning aggregations — dense gatherings of squid depositing and fertilizing eggs. Males and females gather in the spawning grounds, and density increases until individuals are constantly interacting.

But reproductive biology and behavior are complicated for longfin squid. The NEFSC report highlights unique behavior: Females can store sperm from spawning events for later use, and eggs in the same capsule from a single female may have multiple males from multiple spawning events. 

Consort males, typically the larger males, pair up with a single female during spawning. They swim closely alongside her, often guarding her with their arms, and use their size to intimidate competition. Sneaker males, smaller unpaired squid, use stealth and speed to sneak into position with paired females. Males deposit bundles of spermatophores into the female’s mantle cavity or in a pouch located near her head. 

The competition is guided by visual and chemical signals, including pheromones indicating reproductive readiness, rapid color and pattern changes, as well as strategic arm postures and whole-body displays. A 1999 paper published by the Marine Biological Laboratory catalogued 34 visual displays involving colors, brightness, spots, stripes, iridescence, and polarization signals, as well as 17 specific positions and movements used by squid on the spawning grounds. 

Squid were seen flashing white as a signal to repel other squid. Squid displaying this component are almost always engaged in mate guarding, egg laying, or competitive confrontations. Like humans, female squid can blush, displaying a dark patch on one side of the mantle. But when a squid blushes, it functions as a repellent to courting males. And as captivating as these colorful displays can be, squid communication largely remains an encrypted secret to even the most curious scientists. 

“Keith’s rare glimpse of squid in their natural environment beautifully bridges art and science, reminding us that we still have much to learn,” says Hyde, who has centered her research at NOAA on marine ecosystems and fisheries. 

For most people, squid are known solely as seafood or as shadowy legends, chameleons of the sea. Yet each spring, beneath the cool waters of Cape Cod, millions of longfin squid gather in this remarkable reproductive event, a reminder of the rich biodiversity and productivity of Massachusetts marine ecosystems. 

MIT Sea Grant works to support sustainable fisheries and to promote environmental education and stewardship of our coastal and ocean resources. As MIT Sea Grant’s resident artist, Keith Ellenbogen is working on a long-term project to document extraordinary species and ocean events that unfold just off our coast, revealing hidden moments that few have the opportunity to witness. The longfin squid is one of our region’s most valuable marine resources, and these images help reveal one of the most extraordinary events unfolding right off our coast.

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