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      in Security

      Engineers develop a vibrating, ingestible capsule that might help treat obesity

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      When you eat a large meal, your stomach sends signals to your brain that create a feeling of fullness, which helps you realize it’s time to stop eating. A stomach full of liquid can also send these messages, which is why dieters are often advised to drink a glass of water before eating.

      MIT engineers have now come up with a new way to take advantage of that phenomenon, using an ingestible capsule that vibrates within the stomach. These vibrations activate the same stretch receptors that sense when the stomach is distended, creating an illusory sense of fullness.

      In animals who were given this pill 20 minutes before eating, the researchers found that this treatment not only stimulated the release of hormones that signal satiety, but also reduced the animals’ food intake by about 40 percent. Scientists have much more to learn about the mechanisms that influence human body weight, but if further research suggests this technology could be safely used in humans, such a pill might offer a minimally invasive way to treat obesity, the researchers say.

      “For somebody who wants to lose weight or control their appetite, it could be taken before each meal,” says Shriya Srinivasan PhD ’20, a former MIT graduate student and postdoc who is now an assistant professor of bioengineering at Harvard University. “This could be really interesting in that it would provide an option that could minimize the side effects that we see with the other pharmacological treatments out there.”

      Srinivasan is the lead author of the new study, which appears today in Science Advances. Giovanni Traverso, an associate professor of mechanical engineering at MIT and a gastroenterologist at Brigham and Women’s Hospital, is the senior author of the paper.

      A sense of fullness

      When the stomach becomes distended, specialized cells called mechanoreceptors sense that stretching and send signals to the brain via the vagus nerve. As a result, the brain stimulates production of insulin, as well as hormones such as C-peptide, Pyy, and GLP-1. All of these hormones work together to help people digest their food, feel full, and stop eating. At the same time, levels of ghrelin, a hunger-promoting hormone, go down.

      While a graduate student at MIT, Srinivasan became interested in the idea of controlling this process by artificially stretching the mechanoreceptors that line the stomach, through vibration. Previous research had shown that vibration applied to a muscle can induce a sense that the muscle has stretched farther than it actually has.

      “I wondered if we could activate stretch receptors in the stomach by vibrating them and having them perceive that the entire stomach has been expanded, to create an illusory sense of distension that could modulate hormones and eating patterns,” Srinivasan says.

      As a postdoc in MIT’s Koch Institute for Integrative Cancer Research, Srinivasan worked closely with Traverso’s lab, which has developed many novel approaches to oral delivery of drugs and electronic devices. For this study, Srinivasan, Traverso, and a team of researchers designed a capsule about the size of a multivitamin, that includes a vibrating element. When the pill, which is powered by a small silver oxide battery, reaches the stomach, acidic gastric fluids dissolve a gelatinous membrane that covers the capsule, completing the electronic circuit that activates the vibrating motor.

      In a study in animals, the researchers showed that once the pill begins vibrating, it activates mechanoreceptors, which send signals to the brain through stimulation of the vagus nerve. The researchers tracked hormone levels during the periods when the device was vibrating and found that they mirrored the hormone release patterns seen following a meal, even when the animals had fasted.

      The researchers then tested the effects of this stimulation on the animals’ appetite. They found that when the pill was activated for about 20 minutes, before the animals were offered food, they consumed 40 percent less, on average, than they did when the pill was not activated. The animals also gained weight more slowly during periods when they were treated with the vibrating pill.

      “The behavioral change is profound, and that’s using the endogenous system rather than any exogenous therapeutic. We have the potential to overcome some of the challenges and costs associated with delivery of biologic drugs by modulating the enteric nervous system,” Traverso says.

      The current version of the pill is designed to vibrate for about 30 minutes after arriving in the stomach, but the researchers plan to explore the possibility of adapting it to remain in the stomach for longer periods of time, where it could be turned on and off wirelessly as needed. In the animal studies, the pills passed through the digestive tract within four or five days.

      The study also found that the animals did not show any signs of obstruction, perforation, or other negative impacts while the pill was in their digestive tract.

      An alternative approach

      This type of pill could offer an alternative to the current approaches to treating obesity, the researchers say. Nonmedical interventions such as diet exercise don’t always work, and many of the existing medical interventions are fairly invasive. These include gastric bypass surgery, as well as gastric balloons, which are no longer used widely in the United States due to safety concerns.

      Drugs such as GLP-1 agonists can also aid weight loss, but most of them have to be injected, and they are unaffordable for many people. According to Srinivasan, the MIT capsules could be manufactured at a cost that would make them available to people who don’t have access to more expensive treatment options.

      “For a lot of populations, some of the more effective therapies for obesity are very costly. At scale, our device could be manufactured at a pretty cost-effective price point,” she says. “I’d love to see how this would transform care and therapy for people in global health settings who may not have access to some of the more sophisticated or expensive options that are available today.”

      The researchers now plan to explore ways to scale up the manufacturing of the capsules, which could enable clinical trials in humans. Such studies would be important to learn more about the devices’ safety, as well as determine the best time to swallow the capsule before to a meal and how often it would need to be administered.

      Other authors of the paper include Amro Alshareef, Alexandria Hwang, Ceara Byrne, Johannes Kuosmann, Keiko Ishida, Joshua Jenkins, Sabrina Liu, Wiam Abdalla Mohammed Madani, Alison Hayward, and Niora Fabian.

      The research was funded by the National Institutes of Health, Novo Nordisk, the Department of Mechanical Engineering at MIT, a Schmidt Science Fellowship, and the National Science Foundation. More

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      in Environment

      MIT in the media: 2023 in review

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      It was an eventful trip around the sun for MIT this year, from President Sally Kornbluth’s inauguration and Mark Rober’s Commencement address to Professor Moungi Bawendi winning the Nobel Prize in Chemistry. In 2023 MIT researchers made key advances, detecting a dying star swallowing a planet, exploring the frontiers of artificial intelligence, creating clean energy solutions, inventing tools aimed at earlier detection and diagnosis of cancer, and even exploring the science of spreading kindness. Below are highlights of some of the uplifting people, breakthroughs, and ideas from MIT that made headlines in 2023.

      The gift: Kindness goes viral with Steve HartmanSteve Hartman visited Professor Anette “Peko” Hosoi to explore the science behind whether a single act of kindness can change the world.Full story via CBS News

      Trio wins Nobel Prize in chemistry for work on quantum dots, used in electronics and medical imaging“The motivation really is the basic science. A basic understanding, the curiosity of ‘how does the world work?’” said Professor Moungi Bawendi of the inspiration for his research on quantum dots, for which he was co-awarded the 2023 Nobel Prize in Chemistry.Full story via the Associated Press

      How MIT’s all-women leadership team plans to change science for the betterPresident Sally Kornbluth, Provost Cynthia Barnhart, and Chancellor Melissa Nobles emphasized the importance of representation for women and underrepresented groups in STEM.Full story via Radio Boston

      MIT via community college? Transfer students find a new path to a degreeUndergraduate Subin Kim shared his experience transferring from community college to MIT through the Transfer Scholars Network, which is aimed at helping community college students find a path to four-year universities.Full story via the Christian Science Monitor

      MIT president Sally Kornbluth doesn’t think we can hit the pause button on AIPresident Kornbluth discussed the future of AI, ethics in science, and climate change with columnist Shirley Leung on her new “Say More” podcast. “I view [the climate crisis] as an existential issue to the extent that if we don’t take action there, all of the many, many other things that we’re working on, not that they’ll be irrelevant, but they’ll pale in comparison,” Kornbluth said.Full story via The Boston Globe 

      It’s the end of a world as we know itAstronomers from MIT, Harvard University, Caltech and elsewhere spotted a dying star swallowing a large planet. Postdoc Kishalay De explained that: “Finding an event like this really puts all of the theories that have been out there to the most stringent tests possible. It really opens up this entire new field of research.”Full story via The New York Times

      Frontiers of AI

      Hey, Alexa, what should students learn about AI?The Day of AI is a program developed by the MIT RAISE initiative aimed at introducing and teaching K-12 students about AI. “We want students to be informed, responsible users and informed, responsible designers of these technologies,” said Professor Cynthia Breazeal, dean of digital learning at MIT.Full story via The New York Times

      AI tipping pointFour faculty members from across MIT — Professors Song Han, Simon Johnson, Yoon Kim and Rosalind Picard — described the opportunities and risks posed by the rapid advancements in the field of AI.Full story via Curiosity Stream 

      A look into the future of AI at MIT’s robotics laboratoryProfessor Daniela Rus, director of MIT’s Computer Science and Artificial Intelligence Laboratory, discussed the future of artificial intelligence, robotics, and machine learning, emphasizing the importance of balancing the development of new technologies with the need to ensure they are deployed in a way that benefits humanity.Full story via Mashable

      Health care providers say artificial intelligence could transform medicineProfessor Regina Barzilay spoke about her work developing new AI systems that could be used to help diagnose breast and lung cancer before the cancers are detectable to the human eye.Full story via Chronicle

      Is AI coming for your job? Tech experts weigh in: “They don’t replace human labor”Professor David Autor discussed how the rise of artificial intelligence could change the quality of jobs available.Full story via CBS News

      Big tech is bad. Big AI will be worse.Institute Professor Daron Acemoglu and Professor Simon Johnson made the case that “rather than machine intelligence, what we need is ‘machine usefulness,’ which emphasizes the ability of computers to augment human capabilities.”Full story via The New York Times

      Engineering excitement

      MIT’s 3D-printed hearts could pump new life into customized treatments MIT engineers developed a technique for 3D printing a soft, flexible, custom-designed replica of a patient’s heart.Full story via WBUR

      Mystery of why Roman buildings have survived so long has been unraveled, scientists sayScientists from MIT and other institutions discovered that ancient Romans used lime clasts when manufacturing concrete, giving the material self-healing properties.Full story via CNN

      The most interesting startup in America is in Massachusetts. You’ve probably never heard of it.VulcanForms, an MIT startup, is at the “leading edge of a push to transform 3D printing from a niche technology — best known for new-product prototyping and art-class experimentation — into an industrial force.”Full story via The Boston Globe

      Catalyzing climate innovations

      Can Boston’s energy innovators save the world?Boston Magazine reporter Rowan Jacobsen spotlighted how MIT faculty, students, and alumni are leading the charge in clean energy startups. “When it comes to game-changing breakthroughs in energy, three letters keep surfacing again and again: MIT,” writes Jacobsen.Full story via Boston Magazine

      MIT research could be game changer in combating water shortagesMIT researchers discovered that a common hydrogel used in cosmetic creams, industrial coatings, and pharmaceutical capsules can absorb moisture from the atmosphere even as the temperature rises. “For a planet that’s getting hotter, this could be a game-changing discovery.”Full story via NBC Boston

      Energy-storing concrete could form foundations for solar-powered homesMIT engineers uncovered a new way of creating an energy supercapacitor by combining cement, carbon black, and water that could one day be used to power homes or electric vehicles.Full story via New Scientist

      MIT researchers tackle key question of EV adoption: When to charge?MIT scientists found that delayed charging and strategic placement of EV charging stations could help reduce additional energy demands caused by more widespread EV adoption.Full story via Fast Company

      Building better buildingsProfessor John Fernández examined how to reduce the climate footprints of homes and office buildings, recommending creating airtight structures, switching to cleaner heating sources, using more environmentally friendly building materials, and retrofitting existing homes and offices.Full story via The New York Times

      They’re building an “ice penetrator” on a hillside in WestfordResearchers from MIT’s Haystack Observatory built an “ice penetrator,” a device designed to monitor the changing conditions of sea ice.Full story via The Boston Globe

      Healing health solutions

      How Boston is beating cancerMIT researchers are developing drug-delivery nanoparticles aimed at targeting cancer cells without disturbing healthy cells. Essentially, the nanoparticles are “engineered for selectivity,” explained Professor Paula Hammond, head of MIT’s Department of Chemical Engineering.Full story via Boston Magazine

      A new antibiotic, discovered with artificial intelligence, may defeat a dangerous superbugUsing a machine-learning algorithm, researchers from MIT discovered a type of antibiotic that’s effective against a particular strain of drug-resistant bacteria.Full story via CNN

      To detect breast cancer sooner, an MIT professor designs an ultrasound braMIT researchers designed a wearable ultrasound device that attaches to a bra and could be used to detect early-stage breast tumors.Full story via STAT

      The quest for a switch to turn on hungerAn ingestible pill developed by MIT scientists can raise levels of hormones to help increase appetite and decrease nausea in patients with gastroparesis.Full story via Wired

      Here’s how to use dreams for creative inspirationMIT scientists found that the earlier stages of sleep are key to sparking creativity and that people can be guided to dream about specific topics, further boosting creativity.Full story via Scientific American

      Astounding art

      An AI opera from 1987 reboots for a new generationProfessor Tod Machover discussed the restaging of his opera “VALIS” at MIT, which featured an artificial intelligence-assisted musical instrument developed by Nina Masuelli ’23.Full story via The Boston Globe

      Surfacing the stories hidden in migration dataAssociate Professor Sarah Williams discussed the Civic Data Design Lab’s “Motivational Tapestry,” a large woven art piece that uses data from the United Nations World Food Program to visually represent the individual motivations of 1,624 Central Americans who have migrated to the U.S.Full story via Metropolis

      Augmented reality-infused production of Wagner’s “Parsifal” opens Bayreuth FestivalProfessor Jay Scheib’s augmented reality-infused production of Richard Wagner’s “Parsifal” brought “fantastical images” to audience members.Full story via the Associated Press

      Understanding our universe

      New image reveals violent events near a supermassive black holeScientists captured a new image of M87*, the black hole at the center of the Messier 87 galaxy, showing the “launching point of a colossal jet of high-energy particles shooting outward into space.”Full story via Reuters

      Gravitational waves: A new universeMIT researchers Lisa Barsotti, Deep Chatterjee, and Victoria Xu explored how advances in gravitational wave detection are enabling a better understanding of the universe.Full story via Curiosity Stream 

      Nergis Mavalvala helped detect the first gravitational wave. Her work doesn’t stop thereProfessor Nergis Mavalvala, dean of the School of Science, discussed her work searching for gravitational waves, the importance of skepticism in scientific research, and why she enjoys working with young people.Full story via Wired

      Hitting the books

      “The Transcendent Brain” review: Beyond ones and zeroesIn his book “The Transcendent Brain: Spirituality in the Age of Science,” Alan Lightman, a professor of the practice of humanities, displayed his gift for “distilling complex ideas and emotions to their bright essence.”Full story via The Wall Street Journal

      What happens when CEOs treat workers better? Companies (and workers) win.Professor of the practice Zeynep Ton published a book, “The Case for Good Jobs,” and is “on a mission to change how company leaders think, and how they treat their employees.”Full story via The Boston Globe

      How to wage war on conspiracy theoriesProfessor Adam Berinsky’s book, “Political Rumors: Why We Accept Misinformation and How to Fight it,” examined “attitudes toward both politics and health, both of which are undermined by distrust and misinformation in ways that cause harm to both individuals and society.”Full story via Politico

      What it takes for Mexican coders to cross the cultural border with Silicon ValleyAssistant Professor Héctor Beltrán discussed his new book, “Code Work: Hacking across the U.S./México Techno-Borderlands,” which explores the culture of hackathons and entrepreneurship in Mexico.Full story via Marketplace

      Cultivating community

      The Indigenous rocketeerNicole McGaa, a fourth-year student at MIT, discussed her work leading MIT’s all-Indigenous rocket team at the 2023 First Nations Launch National Rocket Competition.Full story via Nature

      “You totally got this,” YouTube star and former NASA engineer Mark Rober tells MIT graduatesDuring his Commencement address at MIT, Mark Rober urged graduates to embrace their accomplishments and boldly face any challenges they encounter.Full story via The Boston Globe

      MIT Juggling Club going strong after half centuryAfter almost 50 years, the MIT Juggling Club, which was founded in 1975 and then merged with a unicycle club, is the oldest drop-in juggling club in continuous operation and still welcomes any aspiring jugglers to come toss a ball (or three) into the air.Full story via Cambridge Day

      Volpe Transportation Center opens as part of $750 million deal between MIT and fedsThe John A. Volpe National Transportation Systems Center in Kendall Square was the first building to open in MIT’s redevelopment of the 14-acre Volpe site that will ultimately include “research labs, retail, affordable housing, and open space, with the goal of not only encouraging innovation, but also enhancing the surrounding community.”Full story via The Boston Globe

      Sparking conversation

      The future of AI innovation and the role of academics in shaping itProfessor Daniela Rus emphasized the central role universities play in fostering innovation and the importance of ensuring universities have the computing resources necessary to help tackle major global challenges.Full story via The Boston Globe

      Moving the needle on supply chain sustainabilityProfessor Yossi Sheffi examined several strategies companies could use to help improve supply chain sustainability, including redesigning last-mile deliveries, influencing consumer choices and incentivizing returnable containers.Full story via The Hill

      Expelled from the mountain top?Sylvester James Gates Jr. ’73, PhD ’77 made the case that “diverse learning environments expose students to a broader range of perspectives, enhance education, and inculcate creativity and innovative habits of mind.”Full story via Science

      Marketing magic of “Barbie” movie has lessons for women’s sportsMIT Sloan Lecturer Shira Springer explored how the success of the “Barbie” movie could be applied to women’s sports.Full story via Sports Business Journal

      We’re already paying for universal health care. Why don’t we have it?Professor Amy Finkelstein asserted that the solution to health insurance reform in the U.S. is “universal coverage that is automatic, free and basic.”Full story via The New York Times 

      The internet could be so good. Really.Professor Deb Roy described how “new kinds of social networks can be designed for constructive communication — for listening, dialogue, deliberation, and mediation — and they can actually work.”Full story via The Atlantic

      Fostering educational excellence

      MIT students give legendary linear algebra professor standing ovation in last lectureAfter 63 years of teaching and over 10 million views of his online lectures, Professor Gilbert Strang received a standing ovation after his last lecture on linear algebra. “I am so grateful to everyone who likes linear algebra and sees its importance. So many universities (and even high schools) now appreciate how beautiful it is and how valuable it is,” said Strang.Full story via USA Today

      “Brave Behind Bars”: Reshaping the lives of inmates through coding classesGraduate students Martin Nisser and Marisa Gaetz co-founded Brave Behind Bars, a program designed to provide incarcerated individuals with coding and digital literacy skills to better prepare them for life after prison.Full story via MSNBC

      Melrose TikTok user “Ms. Nuclear Energy” teaching about nuclear power through social mediaGraduate student Kaylee Cunningham discussed her work using social media to help educate and inform the public about nuclear energy.Full story via CBS Boston  More

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      in Energy

      Accelerated climate action needed to sharply reduce current risks to life and life-support systems

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      Hottest day on record. Hottest month on record. Extreme marine heatwaves. Record-low Antarctic sea-ice.

      While El Niño is a short-term factor in this year’s record-breaking heat, human-caused climate change is the long-term driver. And as global warming edges closer to 1.5 degrees Celsius — the aspirational upper limit set in the Paris Agreement in 2015 — ushering in more intense and frequent heatwaves, floods, wildfires, and other climate extremes much sooner than many expected, current greenhouse gas emissions-reduction policies are far too weak to keep the planet from exceeding that threshold. In fact, on roughly one-third of days in 2023, the average global temperature was at least 1.5 C higher than pre-industrial levels. Faster and bolder action will be needed — from the in-progress United Nations Climate Change Conference (COP28) and beyond — to stabilize the climate and minimize risks to human (and nonhuman) lives and the life-support systems (e.g., food, water, shelter, and more) upon which they depend.

      Quantifying the risks posed by simply maintaining existing climate policies — and the benefits (i.e., avoided damages and costs) of accelerated climate action aligned with the 1.5 C goal — is the central task of the 2023 Global Change Outlook, recently released by the MIT Joint Program on the Science and Policy of Global Change.

      Based on a rigorous, integrated analysis of population and economic growth, technological change, Paris Agreement emissions-reduction pledges (Nationally Determined Contributions, or NDCs), geopolitical tensions, and other factors, the report presents the MIT Joint Program’s latest projections for the future of the earth’s energy, food, water, and climate systems, as well as prospects for achieving the Paris Agreement’s short- and long-term climate goals.

      The 2023 Global Change Outlook performs its risk-benefit analysis by focusing on two scenarios. The first, Current Trends, assumes that Paris Agreement NDCs are implemented through the year 2030, and maintained thereafter. While this scenario represents an unprecedented global commitment to limit greenhouse gas emissions, it neither stabilizes climate nor limits climate change. The second scenario, Accelerated Actions, extends from the Paris Agreement’s initial NDCs and aligns with its long-term goals. This scenario aims to limit and stabilize human-induced global climate warming to 1.5 C by the end of this century with at least a 50 percent probability. Uncertainty is quantified using 400-member ensembles of projections for each scenario.

      This year’s report also includes a visualization tool that enables a higher-resolution exploration of both scenarios.

      Energy

      Between 2020 and 2050, population and economic growth are projected to drive continued increases in energy needs and electrification. Successful achievement of current Paris Agreement pledges will reinforce a shift away from fossil fuels, but additional actions will be required to accelerate the energy transition needed to cap global warming at 1.5 C by 2100.

      During this 30-year period under the Current Trends scenario, the share of fossil fuels in the global energy mix drops from 80 percent to 70 percent. Variable renewable energy (wind and solar) is the fastest growing energy source with more than an 8.6-fold increase. In the Accelerated Actions scenario, the share of low-carbon energy sources grows from 20 percent to slightly more than 60 percent, a much faster growth rate than in the Current Trends scenario; wind and solar energy undergo more than a 13.3-fold increase.

      While the electric power sector is expected to successfully scale up (with electricity production increasing by 73 percent under Current Trends, and 87 percent under Accelerated Actions) to accommodate increased demand (particularly for variable renewables), other sectors face stiffer challenges in their efforts to decarbonize.

      “Due to a sizeable need for hydrocarbons in the form of liquid and gaseous fuels for sectors such as heavy-duty long-distance transport, high-temperature industrial heat, agriculture, and chemical production, hydrogen-based fuels and renewable natural gas remain attractive options, but the challenges related to their scaling opportunities and costs must be resolved,” says MIT Joint Program Deputy Director Sergey Paltsev, a lead author of the 2023 Global Change Outlook.

      Water, food, and land

      With a global population projected to reach 9.9 billion by 2050, the Current Trends scenario indicates that more than half of the world’s population will experience pressures to its water supply, and that three of every 10 people will live in water basins where compounding societal and environmental pressures on water resources will be experienced. Population projections under combined water stress in all scenarios reveal that the Accelerated Actions scenario can reduce approximately 40 million of the additional 570 million people living in water-stressed basins at mid-century.

      Under the Current Trends scenario, agriculture and food production will keep growing. This will increase pressure for land-use change, water use, and use of energy-intensive inputs, which will also lead to higher greenhouse gas emissions. Under the Accelerated Actions scenario, less agricultural and food output is observed by 2050 compared to the Current Trends scenario, since this scenario affects economic growth and increases production costs. Livestock production is more greenhouse gas emissions-intensive than crop and food production, which, under carbon-pricing policies, drives demand downward and increases costs and prices. Such impacts are transmitted to the food sector and imply lower consumption of livestock-based products.

      Land-use changes in the Accelerated Actions scenario are similar to those in the Current Trends scenario by 2050, except for land dedicated to bioenergy production. At the world level, the Accelerated Actions scenario requires cropland area to increase by 1 percent and pastureland to decrease by 4.2 percent, but land use for bioenergy must increase by 44 percent.

      Climate trends

      Under the Current Trends scenario, the world is likely (more than 50 percent probability) to exceed 2 C global climate warming by 2060, 2.8 C by 2100, and 3.8 C by 2150. Our latest climate-model information indicates that maximum temperatures will likely outpace mean temperature trends over much of North and South America, Europe, northern and southeast Asia, and southern parts of Africa and Australasia. So as human-forced climate warming intensifies, these regions are expected to experience more pronounced record-breaking extreme heat events.

      Under the Accelerated Actions scenario, global temperature will continue to rise through the next two decades. But by 2050, global temperature will stabilize, and then slightly decline through the latter half of the century.

      “By 2100, the Accelerated Actions scenario indicates that the world can be virtually assured of remaining below 2 C of global warming,” says MIT Joint Program Deputy Director C. Adam Schlosser, a lead author of the report. “Nevertheless, additional policy mechanisms must be designed with more comprehensive targets that also support a cleaner environment, sustainable resources, as well as improved and equitable human health.”

      The Accelerated Actions scenario not only stabilizes global precipitation increase (by 2060), but substantially reduces the magnitude and potential range of increases to almost one-third of Current Trends global precipitation changes. Any global increase in precipitation heightens flood risk worldwide, so policies aligned with the Accelerated Actions scenario would considerably reduce that risk.

      Prospects for meeting Paris Agreement climate goals

      Numerous countries and regions are progressing in fulfilling their Paris Agreement pledges. Many have declared more ambitious greenhouse gas emissions-mitigation goals, while financing to assist the least-developed countries in sustainable development is not forthcoming at the levels needed. In this year’s Global Stocktake Synthesis Report, the U.N. Framework Convention on Climate Change evaluated emissions reductions communicated by the parties of the Paris Agreement and concluded that global emissions are not on track to fulfill the most ambitious long-term global temperature goals of the Paris Agreement (to keep warming well below 2 C — and, ideally, 1.5 C — above pre-industrial levels), and there is a rapidly narrowing window to raise ambition and implement existing commitments in order to achieve those targets. The Current Trends scenario arrives at the same conclusion.

      The 2023 Global Change Outlook finds that both global temperature targets remain achievable, but require much deeper near-term emissions reductions than those embodied in current NDCs.

      Reducing climate risk

      This report explores two well-known sets of risks posed by climate change. Research highlighted indicates that elevated climate-related physical risks will continue to evolve by mid-century, along with heightened transition risks that arise from shifts in the political, technological, social, and economic landscapes that are likely to occur during the transition to a low-carbon economy.

      “Our Outlook shows that without aggressive actions the world will surpass critical greenhouse gas concentration thresholds and climate targets in the coming decades,” says MIT Joint Program Director Ronald Prinn. “While the costs of inaction are getting higher, the costs of action are more manageable.” More

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      in Environment

      A mineral produced by plate tectonics has a global cooling effect, study finds

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      MIT geologists have found that a clay mineral on the seafloor, called smectite, has a surprisingly powerful ability to sequester carbon over millions of years.

      Under a microscope, a single grain of the clay resembles the folds of an accordion. These folds are known to be effective traps for organic carbon.

      Now, the MIT team has shown that the carbon-trapping clays are a product of plate tectonics: When oceanic crust crushes against a continental plate, it can bring rocks to the surface that, over time, can weather into minerals including smectite. Eventually, the clay sediment settles back in the ocean, where the minerals trap bits of dead organisms in their microscopic folds. This keeps the organic carbon from being consumed by microbes and expelled back into the atmosphere as carbon dioxide.

      Over millions of years, smectite can have a global effect, helping to cool the entire planet. Through a series of analyses, the researchers showed that smectite was likely produced after several major tectonic events over the last 500 million years. During each tectonic event, the clays trapped enough carbon to cool the Earth and induce the subsequent ice age.

      The findings are the first to show that plate tectonics can trigger ice ages through the production of carbon-trapping smectite.

      These clays can be found in certain tectonically active regions today, and the scientists believe that smectite continues to sequester carbon, providing a natural, albeit slow-acting, buffer against humans’ climate-warming activities.

      “The influence of these unassuming clay minerals has wide-ranging implications for the habitability of planets,” says Joshua Murray, a graduate student in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. “There may even be a modern application for these clays in offsetting some of the carbon that humanity has placed into the atmosphere.”

      Murray and Oliver Jagoutz, professor of geology at MIT, have published their findings today in Nature Geoscience.

      A clear and present clay

      The new study follows up on the team’s previous work, which showed that each of the Earth’s major ice ages was likely triggered by a tectonic event in the tropics. The researchers found that each of these tectonic events exposed ocean rocks called ophiolites to the atmosphere. They put forth the idea that, when a tectonic collision occurs in a tropical region, ophiolites can undergo certain weathering effects, such as exposure to wind, rain, and chemical interactions, that transform the rocks into various minerals, including clays.

      “Those clay minerals, depending on the kinds you create, influence the climate in different ways,” Murray explains.

      At the time, it was unclear which minerals could come out of this weathering effect, and whether and how these minerals could directly contribute to cooling the planet. So, while it appeared there was a link between plate tectonics and ice ages, the exact mechanism by which one could trigger the other was still in question.

      With the new study, the team looked to see whether their proposed tectonic tropical weathering process would produce carbon-trapping minerals, and in quantities that would be sufficient to trigger a global ice age.

      The team first looked through the geologic literature and compiled data on the ways in which major magmatic minerals weather over time, and on the types of clay minerals this weathering can produce. They then worked these measurements into a weathering simulation of different rock types that are known to be exposed in tectonic collisions.

      “Then we look at what happens to these rock types when they break down due to weathering and the influence of a tropical environment, and what minerals form as a result,” Jagoutz says.

      Next, they plugged each weathered, “end-product” mineral into a simulation of the Earth’s carbon cycle to see what effect a given mineral might have, either in interacting with organic carbon, such as bits of dead organisms, or with inorganic, in the form of carbon dioxide in the atmosphere.

      From these analyses, one mineral had a clear presence and effect: smectite. Not only was the clay a naturally weathered product of tropical tectonics, it was also highly effective at trapping organic carbon. In theory, smectite seemed like a solid connection between tectonics and ice ages.

      But were enough of the clays actually present to trigger the previous four ice ages? Ideally, researchers should confirm this by finding smectite in ancient rock layers dating back to each global cooling period.

      “Unfortunately, as clays are buried by other sediments, they get cooked a bit, so we can’t measure them directly,” Murray says. “But we can look for their fingerprints.”

      A slow build

      The team reasoned that, as smectites are a product of ophiolites, these ocean rocks also bear characteristic elements such as nickel and chromium, which would be preserved in ancient sediments. If smectites were present in the past, nickel and chromium should be as well.

      To test this idea, the team looked through a database containing thousands of oceanic sedimentary rocks that were deposited over the last 500 million years. Over this time period, the Earth experienced four separate ice ages. Looking at rocks around each of these periods, the researchers observed large spikes of nickel and chromium, and inferred from this that smectite must also have been present.

      By their estimates, the clay mineral could have increased the preservation of organic carbon by less than one-tenth of a percent. In absolute terms, this is a miniscule amount. But over millions of years, they calculated that the clay’s accumulated, sequestered carbon was enough to trigger each of the four major ice ages.

      “We found that you really don’t need much of this material to have a huge effect on the climate,” Jagoutz says.

      “These clays also have probably contributed some of the Earth’s cooling in the last 3 to 5 million years, before humans got involved,” Murray adds. “In the absence of humans, these clays are probably making a difference to the climate. It’s just such a slow process.”

      “Jagoutz and Murray’s work is a nice demonstration of how important it is to consider all biotic and physical components of the global carbon cycle,” says Lee Kump, a professor of geosciences at Penn State University, who was not involved with the study. “Feedbacks among all these components control atmospheric greenhouse gas concentrations on all time scales, from the annual rise and fall of atmospheric carbon dioxide levels to the swings from icehouse to greenhouse over millions of years.”

      Could smectites be harnessed intentionally to further bring down the world’s carbon emissions? Murray sees some potential, for instance to shore up carbon reservoirs such as regions of permafrost. Warming temperatures are predicted to melt permafrost and expose long-buried organic carbon. If smectites could be applied to these regions, the clays could prevent this exposed carbon from escaping into and further warming the atmosphere.

      “If you want to understand how nature works, you have to understand it on the mineral and grain scale,” Jagoutz says. “And this is also the way forward for us to find solutions for this climatic catastrophe. If you study these natural processes, there’s a good chance you will stumble on something that will be actually useful.”

      This research was funded, in part, by the National Science Foundation. More

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      in Energy

      New study shows how universities are critical to emerging fusion industry

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      A new study suggests that universities have an essential role to fulfill in the continued growth and success of any modern high-tech industry, and especially the nascent fusion industry; however, the importance of that role is not reflected in the number of fusion-oriented faculty and educational channels currently available. Academia’s responsiveness to the birth of other modern scientific fields, such as aeronautics and nuclear fission, provides a template for the steps universities can take to enable a robust fusion industry.

      Authored by Dennis Whyte, the Hitachi America Professor of Engineering and director of the Plasma Science and Fusion Center at MIT; Carlos Paz-Soldan, associate professor of applied physics and applied mathematics at Columbia University; and Brian D. Wirth, the Governor’s Chair Professor of Computational Nuclear Engineering at the University of Tennessee, the paper was recently published in the journal Physics of Plasmas as part of a special collection titled “Private Fusion Research: Opportunities and Challenges in Plasma Science.”

      With contributions from authors in academia, government, and private industry, the collection outlines a framework for public-private partnerships that will be essential for the success of the fusion industry.

      Now being seen as a potential source of unlimited green energy, fusion is the same process that powers the sun — hydrogen atoms combine to form helium, releasing vast amounts of clean energy in the form of light and heat.

      The excitement surrounding fusion’s arrival has resulted in the proliferation of dozens of for-profit companies positioning themselves at the forefront of the commercial fusion energy industry. In the near future, those companies will require a significant network of fusion-fluent workers to take on varied tasks requiring a range of skills.

      While the authors acknowledge the role of private industry, especially as an increasingly dominant source of research funding, they also show that academia is and will continue to be critical to industry’s development, and it cannot be decoupled from private industry’s growth. Despite the evidence of this burgeoning interest, the size and scale of the field’s academic network at U.S.-based universities is sparse.

      According to Whyte, “Diversifying the [fusion] field by adding more tracks for master’s students and undergraduates who can transition into industry more quickly is an important step.”

      An analysis found that while there are 57 universities in the United States active in plasma and fusion research, the average number of tenured or tenure-track plasma/fusion faculty at each institution is only two. By comparison, a sampling of US News and World Report’s top 10 programs for nuclear fission and aeronautics/astronautics found an average of nearly 20 faculty devoted to fission and 32 to aero/astro.

      “University programs in fusion and their sponsors need to up their game and hire additional faculty if they want to provide the necessary workforce to support a growing U.S. fusion industry,” adds Paz-Soldan.

      The growth and proliferation of those fields and others, such as computing and biotechnology, were historically in lockstep with the creation of academic programs that helped drive the fields’ progress and widespread acceptance. Creating a similar path for fusion is essential to ensuring its sustainable growth, and as Wirth notes, “that this growth should be pursued in a way that is interdisciplinary across numerous engineering and science disciplines.”

      At MIT, an example of that path is seen at the Plasma Science and Fusion Center.

      The center has deep historical ties to government research programs, and the largest fusion company in the world, Commonwealth Fusion Systems (CFS), was spun out of the PSFC by Whyte’s former students and an MIT postdoc. Whyte also serves as the primary investigator in collaborative research with CFS on SPARC, a proof-of-concept fusion platform for advancing tokamak science that is scheduled for completion in 2025.

      “Public and private roles in the fusion community are rapidly evolving in response to the growth of privately funded commercial product development,” says Michael Segal, head of open innovation at CFS. “The fusion industry will increasingly rely on its university partners to train students, work across diverse disciplines, and execute small and midsize programs at speed.”

      According to the authors, another key reason academia will remain essential to the continued growth and development of fusion is because it is unconflicted. Whyte comments, “Our mandate is sharing information and education, which means we have no competitive conflict and innovation can flow freely.” Furthermore, fusion science is inherently multidisciplinary: “[It] requires physicists, computer scientists, engineers, chemists, etc. and it’s easy to tap into all those disciplines in an academic environment where they’re all naturally rubbing elbows and collaborating.”

      Creating a new energy industry, however, will also require a workforce skilled in disciplines other than STEM, say the authors. As fusion companies continue to grow, they will need expertise in finance, safety, licensing, and market analysis. Any successful fusion enterprise will also have major geopolitical, societal, and economic impacts, all of which must be managed.

      Ultimately, there are several steps the authors identify to help build the connections between academia and industry that will be important going forward: The first is for universities to acknowledge the rapidly changing fusion landscape and begin to adapt. “Universities need to embrace the growth of the private sector in fusion, recognize the opportunities it provides, and seek out mutually beneficial partnerships,” says Paz-Soldan.

      The second step is to reconcile the mission of educational institutions — unconflicted open access — with condensed timelines and proprietary outputs that come with private partnerships. At the same time, the authors note that private fusion companies should embrace the transparency of academia by publishing and sharing the findings they can through peer-reviewed journals, which will be a necessary part of building the industry’s credibility.

      The last step, the authors say, is for universities to become more flexible and creative in their technology licensing strategies to ensure ideas and innovations find their way from the lab into industry.

      “As an industry, we’re in a unique position because everything is brand new,” Whyte says. “But we’re enough students of history that we can see what’s needed to succeed; quantifying the status of the private and academic landscape is an important strategic touchstone. By drawing attention to the current trajectory, hopefully we’ll be in a better position to work with our colleagues in the public and private sector and make better-informed choices about how to proceed.” More

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      in Energy

      Team engineers nanoparticles using ion irradiation to advance clean energy and fuel conversion

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      MIT researchers and colleagues have demonstrated a way to precisely control the size, composition, and other properties of nanoparticles key to the reactions involved in a variety of clean energy and environmental technologies. They did so by leveraging ion irradiation, a technique in which beams of charged particles bombard a material.

      They went on to show that nanoparticles created this way have superior performance over their conventionally made counterparts.

      “The materials we have worked on could advance several technologies, from fuel cells to generate CO2-free electricity to the production of clean hydrogen feedstocks for the chemical industry [through electrolysis cells],” says Bilge Yildiz, leader of the work and a professor in MIT’s departments of Nuclear Science and Engineering and Materials Science and Engineering.

      Critical catalyst

      Fuel and electrolysis cells both involve electrochemical reactions through three principal parts: two electrodes (a cathode and anode) separated by an electrolyte. The difference between the two cells is that the reactions involved run in reverse.

      The electrodes are coated with catalysts, or materials that make the reactions involved go faster. But a critical catalyst made of metal-oxide materials has been limited by challenges including low durability. “The metal catalyst particles coarsen at high temperatures, and you lose surface area and activity as a result,” says Yildiz, who is also affiliated with the Materials Research Laboratory and is an author of an open-access paper on the work published in the journal Energy & Environmental Science.

      Enter metal exsolution, which involves precipitating metal nanoparticles out of a host oxide onto the surface of the electrode. The particles embed themselves into the electrode, “and that anchoring makes them more stable,” says Yildiz. As a result, exsolution has “led to remarkable progress in clean energy conversion and energy-efficient computing devices,” the researchers write in their paper.

      However, controlling the precise properties of the resulting nanoparticles has been difficult. “We know that exsolution can give us stable and active nanoparticles, but the challenging part is really to control it. The novelty of this work is that we’ve found a tool — ion irradiation — that can give us that control,” says Jiayue Wang PhD ’22, first author of the paper. Wang, who conducted the work while earning his PhD in the MIT Department of Nuclear Science and Engineering, is now a postdoc at Stanford University.

      Sossina Haile ’86, PhD ’92, the Walter P. Murphy Professor of Materials Science and Engineering at Northwestern University, who was not involved in the current work, says:

      “Metallic nanoparticles serve as catalysts in a whole host of reactions, including the important reaction of splitting water to generate hydrogen for energy storage. In this work, Yildiz and colleagues have created an ingenious method for controlling the way that nanoparticles form.”

      Haile continues, “the community has shown that exsolution results in structurally stable nanoparticles, but the process is not easy to control, so one doesn’t necessarily get the optimal number and size of particles. Using ion irradiation, this group was able to precisely control the features of the nanoparticles, resulting in excellent catalytic activity for water splitting.”

      What they did

      The researchers found that aiming a beam of ions at the electrode while simultaneously exsolving metal nanoparticles onto the electrode’s surface allowed them to control several properties of the resulting nanoparticles.

      “Through ion-matter interactions, we have successfully engineered the size, composition, density, and location of the exsolved nanoparticles,” the team writes in Energy & Environmental Science.

      For example, they could make the particles much smaller — down to 2 billionths of a meter in diameter — than those made using conventional thermal exsolution methods alone. Further, they were able to change the composition of the nanoparticles by irradiating with specific elements. They demonstrated this with a beam of nickel ions that implanted nickel into the exsolved metal nanoparticle. As a result, they demonstrated a direct and convenient way to engineer the composition of exsolved nanoparticles.

      “We want to have multi-element nanoparticles, or alloys, because they usually have higher catalytic activity,” Yildiz says. “With our approach, the exsolution target does not have to be dependent on the substrate oxide itself.” Irradiation opens the door to many more compositions. “We can pretty much choose any oxide and any ion that we can irradiate with and exsolve that,” says Yildiz.

      The team also found that ion irradiation forms defects in the electrode itself. And these defects provide additional nucleation sites, or places for the exsolved nanoparticles to grow from, increasing the density of the resulting nanoparticles.

      Irradiation could also allow extreme spatial control over the nanoparticles. “Because you can focus the ion beam, you can imagine that you could ‘write’ with it to form specific nanostructures,” says Wang. “We did a preliminary demonstration [of that], but we believe it has potential to realize well-controlled micro- and nano-structures.”

      The team also showed that the nanoparticles they created with ion irradiation had superior catalytic activity over those created by conventional thermal exsolution alone.

      Additional MIT authors of the paper are Kevin B. Woller, a principal research scientist at the Plasma Science and Fusion Center (PSFC), home to the equipment used for ion irradiation; Abinash Kumar PhD ’22, who received his PhD from the Department of Materials Science and Engineering (DMSE) and is now at Oak Ridge National Laboratory; and James M. LeBeau, an associate professor in DMSE. Other authors are Zhan Zhang and Hua Zhou of Argonne National Laboratory, and Iradwikanari Waluyo and Adrian Hunt of Brookhaven National Laboratory.

      This work was funded by the OxEon Corp. and MIT’s PSFC. The research also used resources supported by the U.S. Department of Energy Office of Science, MIT’s Materials Research Laboratory, and MIT.nano. The work was performed, in part, at Harvard University through a network funded by the National Science Foundation. More

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      in Environment

      Merging science and systems thinking to make materials more sustainable

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      For Professor Elsa Olivetti, tackling a problem as large and complex as climate change requires not only lab research but also understanding the systems of production that power the global economy.

      Her career path reflects a quest to investigate materials at scales ranging from the microscopic to the mass-manufactured.

      “I’ve always known what questions I wanted to ask, and then set out to build the tools to help me ask those questions,” says Olivetti, the Jerry McAfee Professor in Engineering.

      Olivetti, who earned tenure in 2022 and was recently appointed associate dean of engineering, has sought to equip students with similar skills, whether in the classroom, in her lab group, or through the interdisciplinary programs she leads at MIT. Those efforts have earned her accolades including the Bose Award for Excellence in Teaching, a MacVicar Faculty Fellowship in 2021, and the McDonald Award for Excellence in Mentoring and Advising in 2023.

      “I think to make real progress in sustainability, materials scientists need to think in interdisciplinary, systems-level ways, but at a deep technical level,” Olivetti says. “Supporting my students so that’s something that a lot more people can do is very rewarding for me.”

      Her mission to make materials more sustainable also makes Olivetti grateful [EAO1] she’s at MIT, which has a long tradition of both interdisciplinary collaboration and technical know-how.

      “MIT’s core competencies are well-positioned for bold achievements in climate and sustainability — the deep expertise on the economics side, the frontier knowledge in science, the computational creativity,” Olivetti says. “It’s a really exciting time and place where the key ingredients for progress are simmering in transformative ways.”

      Answering the call

      The moment that set Olivetti on her life’s journey began when she was 8, with a knock at her door. Her parents were in the other room, so Olivetti opened the door and met an organizer for Greenpeace, a nonprofit that works to raise awareness of environmental issues.

      “I had a chat with that guy and got hooked on environmental concerns,” Olivetti says. “I still remember that conversation.”

      The interaction changed the way Olivetti thought about her place in the world, and her new perspective manifested itself in some unique ways. Her elementary school science fair projects became elaborate pursuits of environmental solutions involving burying various items in the backyard to test for biodegradability. There was also an awkward attempt at natural pesticide development, which lead to a worm hatching in her bedroom.

      As an undergraduate at the University of Virginia, Olivetti gravitated toward classes in environmentalism and materials science.

      “There was a link between materials science and a broader, systems way of framing design for environment, and that just clicked for me in terms of the way I wanted to think about environmental problems — from the atom to the system,” Olivetti recalls.

      That interest led Olivetti to MIT for a PhD in 2001, where she studied the feasibility of new materials for lithium-ion batteries.

      “I really wanted to be thinking of things at a systems level, but I wanted to ground that in lab-based research,” Olivetti says. “I wanted an experiential experience in grad school, and that’s why I chose MIT’s program.”

      Whether it was her undergraduate studies, her PhD, or her ensuing postdoc work at MIT, Olivetti sought to learn new skills to continue bridging the gap between materials science and environmental systems thinking.

      “I think of it as, ‘Here’s how I can build up the ways I ask questions,’” Olivetti explains. “How do we design these materials while thinking about their implications as early as possible?”

      Since joining MIT’s faculty in 2014, Olivetti has developed computational models to measure the cost and environmental impact of new materials, explored ways to adopt more sustainable and circular supply chains, and evaluated potential materials limitations as lithium-ion battery production is scaled. That work helps companies increase their use of greener, recyclable materials and more sustainably dispose of waste.

      Olivetti believes the wide scope of her research gives the students in her lab a more holistic understanding of the life cycle of materials.

      “When the group started, each student was working on a different aspect of the problem — like on the natural language processing pipeline, or on recycling technology assessment, or beneficial use of waste — and now each student can link each of those pieces in their research,” Olivetti explains.

      Beyond her research, Olivetti also co-directs the MIT Climate and Sustainability Consortium, which has established a set of eight areas of sustainability that it organizes coalitions around. Each coalition involves technical leaders at companies and researchers at MIT that work together to accelerate the impact of MIT’s research by helping companies adopt innovative and more sustainable technologies.

      “Climate change mitigation and resilience is such a complex problem, and at MIT we have practice in working together across disciplines on many challenges,” Olivetti says. “It’s been exciting to lean on that culture and unlock ways to move forward more effectively.”

      Bridging divides

      Today, Olivetti tries to maximize the impact of her and her students’ research in materials industrial ecology by maintaining close ties to applications. In her research, this means working directly with aluminum companies to design alloys that could incorporate more scrap material or with nongovernmental organizations to incorporate agricultural residues in building products. In the classroom, that means bringing in people from companies to explain how they think about concepts like heat exchange or fluid flow in their products.

      “I enjoy trying to ground what students are learning in the classroom with what’s happening in the world,” Olivetti explains.

      Exposing students to industry is also a great way to help them think about their own careers. In her research lab, she’s started using the last 30 minutes of meetings to host talks from people working in national labs, startups, and larger companies to show students what they can do after their PhDs. The talks are similar to the Industry Seminar series Olivetti started that pairs undergraduate students with people working in areas like 3D printing, environmental consulting, and manufacturing.

      “It’s about helping students learn what they’re excited about,” Olivetti says.

      Whether in the classroom, lab, or at events held by organizations like MCSC, Olivetti believes collaboration is humanity’s most potent tool to combat climate change.

      “I just really enjoy building links between people,” Olivetti says. “Learning about people and meeting them where they are is a way that one can create effective links. It’s about creating the right playgrounds for people to think and learn.” More

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      in Security

      Microbes could help reduce the need for chemical fertilizers

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      Production of chemical fertilizers accounts for about 1.5 percent of the world’s greenhouse gas emissions. MIT chemists hope to help reduce that carbon footprint by replacing some chemical fertilizer with a more sustainable source — bacteria.

      Bacteria that can convert nitrogen gas to ammonia could not only provide nutrients that plants need, but also help regenerate soil and protect plants from pests. However, these bacteria are sensitive to heat and humidity, so it’s difficult to scale up their manufacture and ship them to farms.

      To overcome that obstacle, MIT chemical engineers have devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function. In a new study, they found that these coated bacteria improved the germination rate of a variety of seeds, including vegetables such as corn and bok choy.

      This coating could make it much easier for farmers to deploy microbes as fertilizers, says Ariel Furst, the Paul M. Cook Career Development Assistant Professor of Chemical Engineering at MIT and the senior author of the study.

      “We can protect them from the drying process, which would allow us to distribute them much more easily and with less cost because they’re a dried powder instead of in liquid,” she says. “They can also withstand heat up to 132 degrees Fahrenheit, which means that you wouldn’t have to use cold storage for these microbes.”

      Benjamin Burke ’23 and postdoc Gang Fan are the lead authors of the open-access paper, which appears in the Journal of the American Chemical Society Au. MIT undergraduate Pris Wasuwanich and Evan Moore ’23 are also authors of the study.

      Protecting microbes

      Chemical fertilizers are manufactured using an energy-intensive process known as Haber-Bosch, which uses extremely high pressures to combine nitrogen from the air with hydrogen to make ammonia.

      In addition to the significant carbon footprint of this process, another drawback to chemical fertilizers is that long-term use eventually depletes the nutrients in the soil. To help restore soil, some farmers have turned to “regenerative agriculture,” which uses a variety of strategies, including crop rotation and composting, to keep soil healthy. Nitrogen-fixing bacteria, which convert nitrogen gas to ammonia, can aid in this approach.

      Some farmers have already begun deploying these “microbial fertilizers,” growing them in large onsite fermenters before applying them to the soil. However, this is cost-prohibitive for many farmers.

      Shipping these bacteria to rural areas is not currently a viable option, because they are susceptible to heat damage. The microbes are also too delicate to survive the freeze-drying process that would make them easier to transport.

      To protect the microbes from both heat and freeze-drying, Furst decided to apply a coating called a metal-phenol network (MPN), which she has previously developed to encapsulate microbes for other uses, such as protecting therapeutic bacteria delivered to the digestive tract.

      The coatings contain two components — a metal and an organic compound called a polyphenol — that can self-assemble into a protective shell. The metals used for the coatings, including iron, manganese, aluminum, and zinc, are considered safe as food additives. Polyphenols, which are often found in plants, include molecules such as tannins and other antioxidants. The FDA classifies many of these polyphenols as GRAS (generally regarded as safe).

      “We are using these natural food-grade compounds that are known to have benefits on their own, and then they form these little suits of armor that protect the microbes,” Furst says.

      For this study, the researchers created 12 different MPNs and used them to encapsulate Pseudomonas chlororaphis, a nitrogen-fixing bacterium that also protects plants against harmful fungi and other pests. They found that all of the coatings protected the bacteria from temperatures up to 50 degrees Celsius (122 degrees Fahrenheit), and also from relative humidity up to 48 percent. The coatings also kept the microbes alive during the freeze-drying process.

      A boost for seeds

      Using microbes coated with the most effective MPN — a combination of manganese and a polyphenol called epigallocatechin gallate (EGCG) — the researchers tested their ability to help seeds germinate in a lab dish. They heated the coated microbes to 50 C before placing them in the dish, and compared them to fresh uncoated microbes and freeze-dried uncoated microbes.

      The researchers found that the coated microbes improved the seeds’ germination rate by 150 percent, compared to seeds treated with fresh, uncoated microbes. This result was consistent across several different types of seeds, including dill, corn, radishes, and bok choy.

      Furst has started a company called Seia Bio to commercialize the coated bacteria for large-scale use in regenerative agriculture. She hopes that the low cost of the manufacturing process will help make microbial fertilizers accessible to small-scale farmers who don’t have the fermenters needed to grow such microbes.

      “When we think about developing technology, we need to intentionally design it to be inexpensive and accessible, and that’s what this technology is. It would help democratize regenerative agriculture,” she says.

      The research was funded by the Army Research Office, a National Institutes of Health New Innovator Award, a National Institute for Environmental Health Sciences Core Center Grant, the CIFAR Azrieli Global Scholars Program, the MIT J-WAFS Program, the MIT Climate and Sustainability Consortium, and the MIT Deshpande Center. More