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    MIT Energy Initiative conference spotlights research priorities amidst a changing energy landscape

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    “We’re here to talk about really substantive changes, and we want you to be a participant in that,” said Desirée Plata, the School of Engineering Distinguished Professor of Climate and Energy in MIT’s Department of Civil and Environmental Engineering, at Energizing@MIT: the MIT Energy Initiative’s (MITEI) Annual Research Conference that was held on Sept. 9-10.Plata’s words resonated with the 150-plus participants from academia, industry, and government meeting in Cambridge for the conference, whose theme was “tackling emerging energy challenges.” Meeting such challenges and ultimately altering the trajectory of global climate outcomes requires partnerships, speakers agreed.“We have to be humble and open,” said Giacomo Silvestri, chair of Eniverse Ventures at Eni, in a shared keynote address. “We cannot develop innovation just focusing on ourselves and our competencies … so we need to partner with startups, venture funds, universities like MIT and other public and private institutions.” Added his Eni colleague, Annalisa Muccioli, head of research and technology, “The energy transition is a race we can win only by combining mature solutions ready to deploy, together with emerging technologies that still require acceleration and risk management.”Research targetsIn a conference that showcased a suite of research priorities MITEI has identified as central to ensuring a low-carbon energy future, participants shared both promising discoveries and strategies for advancing proven technologies in the face of shifting political winds and policy uncertainties.One panel focused on grid resiliency — a topic that has moved from the periphery to the center of energy discourse as climate-driven disruptions, cyber threats, and the integration of renewables challenge legacy systems. A dramatic case in point: the April 2025 outage in Spain and Portugal that left millions without power for eight to 15 hours. “I want to emphasize that this failure was about more than the power system,” said MITEI research scientist Pablo Duenas-Martinez. While he pinpointed technical problems with reactive power and voltage control behind the system collapse, Duenas-Martinez also called out a lack of transmission capacity with Central Europe and out-of-date operating procedures, and recommended better preparation and communication among transmission systems and utility operators.“You can’t plan for every single eventuality, which means we need to broaden the portfolio of extreme events we prepare for,” noted Jennifer Pearce, vice president at energy company Avangrid. “We are making the system smarter, stronger, and more resilient to better protect from a wide range of threats such as storms, flooding, and extreme heat events.” Pearce noted that Avangrid’s commitment to deliver safe, reliable power to its customers necessitates “meticulous emergency planning procedures.”The resiliency of the electric grid under greatly increased demand is an important motivation behind MITEI’s September 2025 launch of the Data Center Power Forum, which was also announced during the annual research conference. The forum will include research projects, webinars, and other content focused on energy supply and storage, grid design and management, infrastructure, and public and economic policy related to data centers. The forum’s members include MITEI companies that also participate in MIT’s Center for Environmental and Energy Policy Research (CEEPR).Storage and transportation: Staggering challengesMeeting climate goals to decarbonize the world by 2050 requires building around 300 terawatt-hours of storage, according to Asegun Henry, a professor in the MIT Department of Mechanical Engineering. “It’s an unbelievably enormous problem people have to wrap their minds around,” he said. Henry has been developing a high-temperature thermal energy storage system he has nicknamed “sun in a box.” His system uses liquid metal and graphite to hold electricity as heat and then convert it back to electricity, enabling storage anywhere from five to 500 hours.“At the end of the day, storage provides a service, and the type of technology that you need is a function of the service that you value the most,” said Nestor Sepulveda, commercial lead for advanced energy investments and partnerships at Google. “I don’t think there is one winner-takes-all type of market here.”Another panel explored sustainable fuels that could help decarbonize hard-to-electrify sectors like aviation, shipping, and long-haul trucking. Randall Field, MITEI’s director of research, noted that sustainably produced drop-in fuels — fuels that are largely compatible with existing engines — “could eliminate potentially trillions of dollars of cost for fleet replacement and for infrastructure build-out, while also helping us to accelerate the rate of decarbonization of the transportation sectors.”Erik G. Birkerts is the chief growth officer of LanzaJet, which produces a drop-in, high-energy-density aviation fuel derived from agricultural residue and other waste carbon sources. “The key to driving broad sustainable aviation fuel adoption is solving both the supply-side challenge through more production and the demand-side hurdle by reducing costs,” he said.“We think a good policy framework [for sustainable fuels] would be something that is technology-neutral, does not exclude any pathways to produce, is based on life cycle accounting practices, and on market mechanisms,” said Veronica L. Robertson, energy products technology portfolio manager at ExxonMobil.MITEI plans a major expansion of its research on sustainable fuels, announcing a two-year study, “The future of fuels: Pathways to sustainable transportation,” starting in early 2026. According to Field, the study will analyze and assess biofuels and e-fuels.Solutions from labs big and smallGlobal energy leaders offered glimpses of their research projects. A panel on carbon capture in power generation featured three takes on the topic: Devin Shaw, commercial director of decarbonization technologies at Shell, described post-combustion carbon capture in power plants using steam for heat recovery; Jan Marsh, a global program lead at Siemens Energy, discussed deploying novel materials to capture carbon dioxide directly from the air; and Jeffrey Goldmeer, senior director of technology strategy at GE Vernova, explained integrating carbon capture into gas-powered turbine systems.During a panel on vehicle electrification, Brian Storey, vice president of energy and materials at the Toyota Research Institute, provided an overview of Toyota’s portfolio of projects for decarbonization, including solid-state batteries, flexible manufacturing lines, and grid-forming inverters to support EV charging infrastructure.A session on MITEI seed fund projects revealed promising early-stage research inside MIT’s own labs. A new process for decarbonizing the production of ethylene was presented by Yogesh Surendranath, Donner Professor of Science in the MIT Department of Chemistry. Materials Science and Engineering assistant professor Aristide Gumyusenge also discussed the development of polymers essential for a new kind of sodium-ion battery.Shepherding bold, new technologies like these from academic labs into the real world cannot succeed without ample support and deft management. A panel on paths to commercialization featured the work of Iwnetim Abate, Chipman Career Development Professor and assistant professor in the MIT Department of Materials Science and Engineering, who has spun out a company, Addis Energy, based on a novel geothermal process for harvesting clean hydrogen and ammonia from subsurface, iron-rich rocks. Among his funders: ARPA-E and MIT’s own The Engine Ventures.The panel also highlighted the MIT Proto Ventures Program, an initiative to seize early-stage MIT ideas and unleash them as world-changing startups. “A mere 4.2 percent of all the patents that are actually prosecuted in the world are ever commercialized, which seems like a shocking number,” said Andrew Inglis, an entrepreneur working with Proto Ventures to translate geothermal discoveries into businesses. “Can’t we do this better? Let’s do this better!”Geopolitical hazardsThroughout the conference, participants often voiced concern about the impacts of competition between the United States and China. Kelly Sims Gallagher, dean of the Fletcher School at Tufts University and an expert on China’s energy landscape, delivered the sobering news in her keynote address: “U.S. competitiveness in low-carbon technologies has eroded in nearly every category,” she said. “The Chinese are winning the clean tech race.”China enjoys a 51 percent share in global wind turbine manufacture and 75 percent in solar modules. It also controls low-carbon supply chains that much of the world depends on. “China is getting so dominant that nobody can carve out a comparative advantage in anything,” said Gallagher. “China is just so big, and the scale is so huge that the Chinese can truly conquer markets and make it very hard for potential competitors to find a way in.”And for the United States, the problem is “the seesaw of energy policy,” she says. “It’s incredibly difficult for the private sector to plan and to operate, given the lack of predictability and policy here.”Nevertheless, Gallagher believes the United States still has a chance of at least regaining competitiveness, by setting up a stable, bipartisan energy policy, rebuilding domestic manufacturing and supply chains; providing consistent fiscal incentives; attracting and retaining global talent; and fostering international collaboration.The conference shone a light on one such collaboration: a China-U.S. joint venture to manufacture lithium iron phosphate batteries for commercial vehicles in the United States. The venture brings together Eve Energy, a Chinese battery technology and manufacturing company; Daimler, a global commercial vehicle manufacturer; PACCAR Inc., a U.S.-based truck manufacturer; and Accelera, the zero-emissions business of Cummins Inc. “Manufacturing batteries in the U.S. makes the supply chain more robust and reduces geopolitical risks,” said Mike Gerty, of PACCAR.While she acknowledged the obstacles confronting her colleagues in the room, Plata nevertheless concluded her remarks as a panel moderator with some optimism: “I hope you all leave this conference and look back on it in the future, saying I was in the room when they actually solved some of the challenges standing between now and the future that we all wish to manifest.” More

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      Introducing the MIT-GE Vernova Climate and Energy Alliance

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      MIT and GE Vernova launched the MIT-GE Vernova Energy and Climate Alliance on Sept. 15, a collaboration to advance research and education focused on accelerating the global energy transition.Through the alliance — an industry-academia initiative conceived by MIT Provost Anantha Chandrakasan and GE Vernova CEO Scott Strazik — GE Vernova has committed $50 million over five years in the form of sponsored research projects and philanthropic funding for research, graduate student fellowships, internships, and experiential learning, as well as professional development programs for GE Vernova leaders.“MIT has a long history of impactful collaborations with industry, and the collaboration between MIT and GE Vernova is a shining example of that legacy,” said Chandrakasan in opening remarks at a launch event. “Together, we are working on energy and climate solutions through interdisciplinary research and diverse perspectives, while providing MIT students the benefit of real-world insights from an industry leader positioned to bring those ideas into the world at scale.”The energy of changeAn independent company since its spinoff from GE in April 2024, GE Vernova is focused on accelerating the global energy transition. The company generates approximately 25 percent of the world’s electricity — with the world’s largest installed base of over 7,000 gas turbines, about 57,000 wind turbines, and leading-edge electrification technology.GE Vernova’s slogan, “The Energy of Change,” is reflected in decisions such as locating its headquarters in Cambridge, Massachusetts — in close proximity to MIT. In pursuing transformative approaches to the energy transition, the company has identified MIT as a key collaborator.A key component of the mission to electrify and decarbonize the world is collaboration, according to CEO Scott Strazik. “We want to inspire, and be inspired by, students as we work together on our generation’s greatest challenge, climate change. We have great ambition for what we want the world to become, but we need collaborators. And we need folks that want to iterate with us on what the world should be from here.”Representing the Healey-Driscoll administration at the launch event were Massachusetts Secretary of Energy and Environmental Affairs Rebecca Tepper and Secretary of the Executive Office of Economic Development Eric Paley. Secretary Tepper highlighted the Mass Leads Act, a $1 billion climate tech and life sciences initiative enacted by Governor Maura Healey last November to strengthen Massachusetts’ leadership in climate tech and AI.“We’re harnessing every part of the state, from hydropower manufacturing facilities to the blue-to-blue economy in our south coast, and right here at the center of our colleges and universities. We want to invent and scale the solutions to climate change in our own backyard,” said Tepper. “That’s been the Massachusetts way for decades.”

      Launch event attendees explore interactive displays in MIT’s Lobby 13.

      Photo: Gretchen Ertl

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      Real-world problems, insights, and solutionsThe launch celebration featured interactive science displays and student presenters introducing the first round of 13 research projects led by MIT faculty. These projects focus on generating scalable solutions to our most pressing challenges in the areas of electrification, decarbonization, renewables acceleration, and digital solutions. Read more about the funded projects here.Collaborating with industry offers the opportunity for researchers and students to address real-world problems informed by practical insights. The diverse, interdisciplinary perspectives from both industry and academia will significantly strengthen the research supported through the GE Vernova Fellowships announced at the launch event.“I’m excited to talk to the industry experts at GE Vernova about the problems that they work on,” said GE Vernova Fellow Aaron Langham. “I’m looking forward to learning more about how real people and industries use electrical power.”Fellow Julia Estrin echoed a similar sentiment: “I see this as a chance to connect fundamental research with practical applications — using insights from industry to shape innovative solutions in the lab that can have a meaningful impact at scale.”GE Vernova’s commitment to research is also providing support and inspiration for fellows. “This level of substantive enthusiasm for new ideas and technology is what comes from a company that not only looks toward the future, but also has the resources and determination to innovate impactfully,” says Owen Mylotte, a GE Vernova Fellow.The inaugural cohort of eight fellows will continue their research at MIT with tuition support from GE Vernova. Find the full list of fellows and their research topics here.Pipeline of future energy leadersHighlighting the alliance’s emphasis on cultivating student talent and leadership, GE Vernova CEO Scott Strazik introduced four MIT alumni who are now leaders at GE Vernova: Dhanush Mariappan SM ’03, PhD ’19, senior engineering manager in the GE Vernova Advanced Research Center; Brent Brunell SM ’00, technology director in the Advanced Research Center; Paolo Marone MBA ’21, CFO of wind; and Grace Caza MAP ’22, chief of staff in supply chain and operations.The four shared their experiences of working with MIT as students and their hopes for the future of this alliance in the realm of “people development,” as Mariappan highlighted. “Energy transition means leaders. And every one of the innovative research and professional education programs that will come out of this alliance is going to produce the leaders of the energy transition industry.”The alliance is underscoring its commitment to developing future energy leaders by supporting the New Engineering Education Transformation program (NEET) and expanding opportunities for student internships. With 100 new internships for MIT students announced in the days following the launch, GE Vernova is opening broad opportunities for MIT students at all levels to contribute to a sustainable future.“GE Vernova has been a tremendous collaborator every step of the way, with a clear vision of the technical breakthroughs we need to affect change at scale and a deep respect for MIT’s strengths and culture, as well as a hunger to listen and learn from us as well,” said Betar Gallant, alliance director who is also the Kendall Rohsenow Associate Professor of Mechanical Engineering at MIT. “Students, take this opportunity to learn, connect, and appreciate how much you’re valued, and how bright your futures are in this area of decarbonizing our energy systems. Your ideas and insight are going to help us determine and drive what’s next.”

      Event attendees mingle in MIT’s Lobby 13.

      Photo: Gretchen Ertl

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      Daring to create the future we wantThe launch event transformed MIT’s Lobby 13 with green lighting and animated conversation around the posters and hardware demos on display, reflecting the sense of optimism for the future and the type of change the alliance — and the Commonwealth of Massachusetts — seeks to advance.“Because of this collaboration and the commitment to the work that needs doing, many things will be created,” said Secretary Paley. “People in this room will work together on all kinds of projects that will do incredible things for our economy, for our innovation, for our country, and for our climate.”The alliance builds on MIT’s growing portfolio of initiatives around sustainable energy systems, including the Climate Project at MIT, a presidential initiative focused on developing solutions to some of the toughest barriers to an effective global climate response. “This new alliance is a significant opportunity to move the needle of energy and climate research as we dare to create the future that we want, with the promise of impactful solutions for the world,” said Evelyn Wang, MIT vice president for energy and climate, who attended the launch.To that end, the alliance is supporting critical cross-institution efforts in energy and climate policy, including funding three master’s students in MIT Technology and Policy Program and hosting an annual symposium in February 2026 to advance interdisciplinary research. GE Vernova is also providing philanthropic support to the MIT Human Insight Collaborative. For 2025-26, this support will contribute to addressing global energy poverty by supporting the MIT Abdul Latif Jameel Poverty Action Lab (J-PAL) in its work to expand access to affordable electricity in South Africa.“Our hope to our fellows, our hope to our students is this: While the stakes are high and the urgency has never been higher, the impact that you are going to have over the decades to come has never been greater,” said Roger Martella, chief corporate and sustainability officer at GE Vernova. “You have so much opportunity to move the world in a better direction. We need you to succeed. And our mission is to serve you and enable your success.”With the alliance’s launch — and GE Vernova’s new membership in several other MIT consortium programs related to sustainability, automation and robotics, and AI, including the Initiative for New Manufacturing, MIT Energy Initiative, MIT Climate and Sustainability Consortium, and Center for Transportation and Logistics — it’s evident why Betar Gallant says the company is “all-in at MIT.”The potential for tremendous impact on the energy industry is clear to those involved in the alliance. As GE Vernova Fellow Jack Morris said at the launch, “This is the beginning of something big.” More

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      From nanoscale to global scale: Advancing MIT’s special initiatives in manufacturing, health, and climate

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      “MIT.nano is essential to making progress in high-priority areas where I believe that MIT has a responsibility to lead,” opened MIT president Sally Kornbluth at the 2025 Nano Summit. “If we harness our collective efforts, we can make a serious positive impact.”It was these collective efforts that drove discussions at the daylong event hosted by MIT.nano and focused on the importance of nanoscience and nanotechnology across MIT’s special initiatives — projects deemed critical to MIT’s mission to help solve the world’s greatest challenges. With each new talk, common themes were reemphasized: collaboration across fields, solutions that can scale up from lab to market, and the use of nanoscale science to enact grand-scale change.“MIT.nano has truly set itself apart, in the Institute’s signature way, with an emphasis on cross-disciplinary collaboration and open access,” said Kornbluth. “Today, you’re going to hear about the transformative impact of nanoscience and nanotechnology, and how working with the very small can help us do big things for the world together.”Collaborating on healthAngela Koehler, faculty director of the MIT Health and Life Sciences Collaborative (MIT HEALS) and the Charles W. and Jennifer C. Johnson Professor of Biological Engineering, opened the first session with a question: How can we build a community across campus to tackle some of the most transformative problems in human health? In response, three speakers shared their work enabling new frontiers in medicine.Ana Jaklenec, principal research scientist at the Koch Institute for Integrative Cancer Research, spoke about single-injection vaccines, and how her team looked to the techniques used in fabrication of electrical engineering components to see how multiple pieces could be packaged into a tiny device. “MIT.nano was instrumental in helping us develop this technology,” she said. “We took something that you can do in microelectronics and the semiconductor industry and brought it to the pharmaceutical industry.”While Jaklenec applied insight from electronics to her work in health care, Giovanni Traverso, the Karl Van Tassel Career Development Professor of Mechanical Engineering, who is also a gastroenterologist at Brigham and Women’s Hospital, found inspiration in nature, studying the cephalopod squid and remora fish to design ingestible drug delivery systems. Representing the industry side of life sciences, Mirai Bio senior vice president Jagesh Shah SM ’95, PhD ’99 presented his company’s precision-targeted lipid nanoparticles for therapeutic delivery. Shah, as well as the other speakers, emphasized the importance of collaboration between industry and academia to make meaningful impact, and the need to strengthen the pipeline for young scientists.Manufacturing, from the classroom to the workforcePaving the way for future generations was similarly emphasized in the second session, which highlighted MIT’s Initiative for New Manufacturing (MIT INM). “MIT’s dedication to manufacturing is not only about technology research and education, it’s also about understanding the landscape of manufacturing, domestically and globally,” said INM co-director A. John Hart, the Class of 1922 Professor and head of the Department of Mechanical Engineering. “It’s about getting people — our graduates who are budding enthusiasts of manufacturing — out of campus and starting and scaling new companies,” he said.On progressing from lab to market, Dan Oran PhD ’21 shared his career trajectory from technician to PhD student to founding his own company, Irradiant Technologies. “How are companies like Dan’s making the move from the lab to prototype to pilot production to demonstration to commercialization?” asked the next speaker, Elisabeth Reynolds, professor of the practice in urban studies and planning at MIT. “The U.S. capital market has not historically been well organized for that kind of support.” She emphasized the challenge of scaling innovations from prototype to production, and the need for workforce development.“Attracting and retaining workforce is a major pain point for manufacturing businesses,” agreed John Liu, principal research scientist in mechanical engineering at MIT. To keep new ideas flowing from the classroom to the factory floor, Liu proposes a new worker type in advanced manufacturing — the technologist — someone who can be a bridge to connect the technicians and the engineers.Bridging ecosystems with nanoscienceBridging people, disciplines, and markets to affect meaningful change was also emphasized by Benedetto Marelli, mission director for the MIT Climate Project and associate professor of civil and environmental engineering at MIT.“If we’re going to have a tangible impact on the trajectory of climate change in the next 10 years, we cannot do it alone,” he said. “We need to take care of ecology, health, mobility, the built environment, food, energy, policies, and trade and industry — and think about these as interconnected topics.”Faculty speakers in this session offered a glimpse of nanoscale solutions for climate resiliency. Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering, presented his group’s work on using nanoparticles to turn waste methane and urea into renewable materials. Desirée Plata, the School of Engineering Distinguished Climate and Energy Professor, spoke about scaling carbon dioxide removal systems. Mechanical engineering professor Kripa Varanasi highlighted, among other projects, his lab’s work on improving agricultural spraying so pesticides adhere to crops, reducing agricultural pollution and cost.In all of these presentations, the MIT faculty highlighted the tie between climate and the economy. “The economic systems that we have today are depleting to our resources, inherently polluting,” emphasized Plata. “The goal here is to use sustainable design to transition the global economy.”What do people do at MIT.nano?This is where MIT.nano comes in, offering shared access facilities where researchers can design creative solutions to these global challenges. “What do people do at MIT.nano?” asked associate director for Fab.nano Jorg Scholvin ’00, MNG ’01, PhD ’06 in the session on MIT.nano’s ecosystem. With 1,500 individuals and over 20 percent of MIT faculty labs using MIT.nano, it’s a difficult question to quickly answer. However, in a rapid-fire research showcase, students and postdocs gave a response that spanned 3D transistors and quantum devices to solar solutions and art restoration. Their work reflects the challenges and opportunities shared at the Nano Summit: developing technologies ready to scale, uniting disciplines to tackle complex problems, and gaining hands-on experience that prepares them to contribute to the future of hard tech.The researchers’ enthusiasm carried the excitement and curiosity that President Kornbluth mentioned in her opening remarks, and that many faculty emphasized throughout the day. “The solutions to the problems we heard about today may come from inventions that don’t exist yet,” said Strano. “These are some of the most creative people, here at MIT. I think we inspire each other.”Robert N. Noyce (1953) Cleanroom at MIT.nanoCollaborative inspiration is not new to the MIT culture. The Nano Summit sessions focused on where we are today, and where we might be going in the future, but also reflected on how we arrived at this moment. Honoring visionaries of nanoscience and nanotechnology, President Emeritus L. Rafael Reif delivered the closing remarks and an exciting announcement — the dedication of the MIT.nano cleanroom complex. Made possible through a gift by Ray Stata SB ’57, SM ’58, this research space, 45,000 square feet of ISO 5, 6, and 7 cleanrooms, will be named the Robert N. Noyce (1953) Cleanroom.“Ray Stata was — and is — the driving force behind nanoscale research at MIT,” said Reif. “I want to thank Ray, whose generosity has allowed MIT to honor Robert Noyce in such a fitting way.”Ray Stata co-founded Analog Devices in 1965, and Noyce co-founded Fairchild Semiconductor in 1957, and later Intel in 1968. Noyce, widely regarded as the “Mayor of Silicon Valley,” became chair of the Semiconductor Industry Association in 1977, and over the next 40 years, semiconductor technology advanced a thousandfold, from micrometers to nanometers.“Noyce was a pioneer of the semiconductor industry,” said Stata. “It is due to his leadership and remarkable contributions that electronics technology is where it is today. It is an honor to be able to name the MIT.nano cleanroom after Bob Noyce, creating a permanent tribute to his vision and accomplishments in the heart of the MIT campus.”To conclude his remarks and the 2025 Nano Summit, Reif brought the nano journey back to today, highlighting technology giants such as Lisa Su ’90, SM ’91, PhD ’94, for whom Building 12, the home of MIT.nano, is named. “MIT has educated a large number of remarkable leaders in the semiconductor space,” said Reif. “Now, with the Robert Noyce Cleanroom, this amazing MIT community is ready to continue to shape the future with the next generation of nano discoveries — and the next generation of nano leaders, who will become living legends in their own time.” More

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      Matthew Shoulders named head of the Department of Chemistry

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      Matthew D. Shoulders, the Class of 1942 Professor of Chemistry, a MacVicar Faculty Fellow, and an associate member of the Broad Institute of MIT and Harvard, has been named head of the MIT Department of Chemistry, effective Jan. 16, 2026. “Matt has made pioneering contributions to the chemistry research community through his research on mechanisms of proteostasis and his development of next-generation techniques to address challenges in biomedicine and agriculture,” says Nergis Mavalvala, dean of the MIT School of Science and the Curtis and Kathleen Marble Professor of Astrophysics. “He is also a dedicated educator, beloved by undergraduates and graduates alike. I know the department will be in good hands as we double down on our commitment to world-leading research and education in the face of financial headwinds.”Shoulders succeeds Troy Van Voorhis, the Robert T. Haslam and Bradley Dewey Professor of Chemistry, who has been at the helm since October 2019.“I am tremendously grateful to Troy for his leadership the past six years, building a fantastic community here in our department. We face challenges, but also many exciting opportunities, as a department in the years to come,” says Shoulders. “One thing is certain: Chemistry innovations are critical to solving pressing global challenges. Through the research that we do and the scientists we train, our department has a huge role to play in shaping the future.”Shoulders studies how cells fold proteins, and he develops ​and applies novel protein engineering techniques to challenges in biotechnology. His work across chemistry and biochemistry fields including proteostasis, extracellular matrix biology, virology, evolution, and synthetic biology is yielding not just important insights into topics like how cells build healthy tissues and how proteins evolve, but also influencing approaches to disease therapy and biotechnology development.“Matt is an outstanding researcher whose work touches on fundamental questions about how the cell machinery directs the synthesis and folding of proteins. His discoveries about how that machinery breaks down as a result of mutations or in response to stress has a fundamental impact on how we think about and treat human diseases,” says Van Voorhis.In one part of Matt’s current research program, he is studying how protein folding systems in cells — known as chaperones — shape the evolution of their clients. Amongst other discoveries, his lab has shown that viral pathogens hijack human chaperones to enable their rapid evolution and escape from host immunity. In related recent work, they have discovered that these same chaperones can promote access to malignancy-driving mutations in tumors. Beyond fundamental insights into evolutionary biology, these findings hold potential to open new therapeutic strategies to target cancer and viral infections.“Matt’s ability to see both the details and the big picture makes him an outstanding researcher and a natural leader for the department,” says Timothy Swager, the John D. MacArthur Professor of Chemistry. “MIT Chemistry can only benefit from his dedication to understanding and addressing the parts and the whole.” Shoulders also leads a food security project through the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS). Shoulders, along with MIT Research Scientist Robbie Wilson, assembled an interdisciplinary team based at MIT to enhance climate resilience in agriculture by improving one of the most inefficient aspects of photosynthesis, the carbon dioxide-fixing plant enzyme RuBisCO. J-WAFS funded this high-risk, high-reward MIT Grand Challenge project in 2023, and it has received further support from federal research agencies and the Grantham Foundation for the Protection of the Environment. “Our collaborative team of biochemists and synthetic biologists, computational biologists, and chemists is deeply integrated with plant biologists, creating a robust feedback loop for enzyme engineering,” Shoulders says. “Together, this team is making a concerted effort using state-of-the-art techniques to engineer crop RuBisCO with an eye to helping make meaningful gains in securing a stable crop supply, hopefully with accompanying improvements in both food and water security.”In addition to his research contributions, Shoulders has taught multiple classes for Course V, including 5.54 (Advances in Chemical Biology) and 5.111 (Principles of Chemical Science), along with a number of other key chemistry classes. His contributions to a 5.111 “bootcamp” through the MITx platform served to address gaps in the classroom curriculum by providing online tools to help undergraduate students better grasp the material in the chemistry General Institute Requirement (GIR). His development of Guided Learning Demonstrations to support first-year chemistry courses at MIT has helped bring the lab to the GIR, and also contributed to the popularity of 5.111 courses offered regularly via MITx.“I have had the pleasure of teaching with Matt on several occasions, and he is a fantastic educator. He is an innovator both inside and outside the classroom and has an unwavering commitment to his students’ success,” says Van Voorhis of Shoulders, who was named a 2022 MacVicar Faculty Fellow, and who received a Committed to Caring award through the Office of Graduate Education.Shoulders also founded the MIT Homeschool Internship Program for Science and Technology, which brings high school students to campus for paid summer research experiences in labs across the Institute.He is a founding member of the Department of Chemistry’s Quality of Life Committee and chair for the last six years, helping to improve all aspects of opportunity, professional development, and experience in the department: “countless changes that have helped make MIT a better place for all,” as Van Voorhis notes, including creating a peer mentoring program for graduate students and establishing universal graduate student exit interviews to collect data for department-wide assessment and improvement.At the Institute level, Shoulders has served on the Committee on Graduate Programs, Committee on Sexual Misconduct Prevention and Response (in which he co-chaired the provost’s working group on the Faculty and Staff Sexual Misconduct Survey), and the Committee on Assessment of Biohazards and Embryonic Stem Cell Research Oversight, among other roles.Shoulders graduated summa cum laude from Virginia Tech in 2004, earning a BS in chemistry with a minor in biochemistry. He earned a PhD in chemistry at the University of Wisconsin at Madison in 2009 under Professor Ronald Raines. Following an American Cancer Society Postdoctoral Fellowship at Scripps Research Institute, working with professors Jeffery Kelly and Luke Wiseman, Shoulders joined the MIT Department of Chemistry faculty as an assistant professor in 2012. Shoulders also serves as an associate member of the Broad Institute and an investigator at the Center for Musculoskeletal Research at Massachusetts General Hospital.Among his many awards, Shoulders has received a NIH Director’s New Innovator Award under the NIH High-Risk, High-Reward Research Program; an NSF CAREER Award; an American Cancer Society Research Scholar Award; the Camille Dreyfus Teacher-Scholar Award; and most recently the Ono Pharma Foundation Breakthrough Science Award. More

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      A cysteine-rich diet may promote regeneration of the intestinal lining, study suggests

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      A diet rich in the amino acid cysteine may have rejuvenating effects in the small intestine, according to a new study from MIT. This amino acid, the researchers discovered, can turn on an immune signaling pathway that helps stem cells to regrow new intestinal tissue.This enhanced regeneration may help to heal injuries from radiation, which often occur in patients undergoing radiation therapy for cancer. The research was conducted in mice, but if future research shows similar results in humans, then delivering elevated quantities of cysteine, through diet or supplements, could offer a new strategy to help damaged tissue heal faster, the researchers say.“The study suggests that if we give these patients a cysteine-rich diet or cysteine supplementation, perhaps we can dampen some of the chemotherapy or radiation-induced injury,” says Omer Yilmaz, director of the MIT Stem Cell Initiative, an associate professor of biology at MIT, and a member of MIT’s Koch Institute for Integrative Cancer Research. “The beauty here is we’re not using a synthetic molecule; we’re exploiting a natural dietary compound.”While previous research has shown that certain types of diets, including low-calorie diets, can enhance intestinal stem cell activity, the new study is the first to identify a single nutrient that can help intestinal cells to regenerate.Yilmaz is the senior author of the study, which appears today in Nature. Koch Institute postdoc Fangtao Chi is the paper’s lead author.Boosting regenerationIt is well-established that diet can affect overall health: High-fat diets can lead to obesity, diabetes, and other health problems, while low-calorie diets have been shown to extend lifespans in many species. In recent years, Yilmaz’s lab has investigated how different types of diets influence stem cell regeneration, and found that high-fat diets, as well as short periods of fasting, can enhance stem cell activity in different ways.“We know that macro diets such as high-sugar diets, high-fat diets, and low-calorie diets have a clear impact on health. But at the granular level, we know much less about how individual nutrients impact stem cell fate decisions, as well as tissue function and overall tissue health,” Yilmaz says.In their new study, the researchers began by feeding mice a diet high in one of 20 different amino acids, the building blocks of proteins. For each group, they measured how the diet affected intestinal stem cell regeneration. Among these amino acids, cysteine had the most dramatic effects on stem cells and progenitor cells (immature cells that differentiate into adult intestinal cells).Further studies revealed that cysteine initiates a chain of events leading to the activation of a population of immune cells called CD8 T cells. When cells in the lining of the intestine absorb cysteine from digested food, they convert it into CoA, a cofactor that is released into the mucosal lining of the intestine. There, CD8 T cells absorb CoA, which stimulates them to begin proliferating and producing a cytokine called IL-22.IL-22 is an important player in the regulation of intestinal stem cell regeneration, but until now, it wasn’t known that CD8 T cells can produce it to boost intestinal stem cells. Once activated, those IL-22-releasing T cells are primed to help combat any kind of injury that could occur within the intestinal lining.“What’s really exciting here is that feeding mice a cysteine-rich diet leads to the expansion of an immune cell population that we typically don’t associate with IL-22 production and the regulation of intestinal stemness,” Yilmaz says. “What happens in a cysteine-rich diet is that the pool of cells that make IL-22 increases, particularly the CD8 T-cell fraction.”These T cells tend to congregate within the lining of the intestine, so they are already in position when needed. The researchers found that the stimulation of CD8 T cells occurred primarily in the small intestine, not in any other part of the digestive tract, which they believe is because most of the protein that we consume is absorbed by the small intestine.Healing the intestineIn this study, the researchers showed that regeneration stimulated by a cysteine-rich diet could help to repair radiation damage to the intestinal lining. Also, in work that has not been published yet, they showed that a high-cysteine diet had a regenerative effect following treatment with a chemotherapy drug called 5-fluorouracil. This drug, which is used to treat colon and pancreatic cancers, can also damage the intestinal lining.Cysteine is found in many high-protein foods, including meat, dairy products, legumes, and nuts. The body can also synthesize its own cysteine, by converting the amino acid methionine to cysteine — a process that takes place in the liver. However, cysteine produced in the liver is distributed through the entire body and doesn’t lead to a buildup in the small intestine the way that consuming cysteine in the diet does.“With our high-cysteine diet, the gut is the first place that sees a high amount of cysteine,” Chi says.Cysteine has been previously shown to have antioxidant effects, which are also beneficial, but this study is the first to demonstrate its effect on intestinal stem cell regeneration. The researchers now hope to study whether it may also help other types of stem cells regenerate new tissues. In one ongoing study, they are investigating whether cysteine might stimulate hair follicle regeneration.They also plan to further investigate some of the other amino acids that appear to influence stem cell regeneration.“I think we’re going to uncover multiple new mechanisms for how these amino acids regulate cell fate decisions and gut health in the small intestine and colon,” Yilmaz says.The research was funded, in part, by the National Institutes of Health, the V Foundation, the Kathy and Curt Marble Cancer Research Award, the Koch Institute-Dana-Farber/Harvard Cancer Center Bridge Project, the American Federation for Aging Research, the MIT Stem Cell Initiative, and the Koch Institute Support (core) Grant from the National Cancer Institute. More

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      in Energy

      MIT engineers develop a magnetic transistor for more energy-efficient electronics

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      Transistors, the building blocks of modern electronics, are typically made of silicon. Because it’s a semiconductor, this material can control the flow of electricity in a circuit. But silicon has fundamental physical limits that restrict how compact and energy-efficient a transistor can be.MIT researchers have now replaced silicon with a magnetic semiconductor, creating a magnetic transistor that could enable smaller, faster, and more energy-efficient circuits. The material’s magnetism strongly influences its electronic behavior, leading to more efficient control of the flow of electricity. The team used a novel magnetic material and an optimization process that reduces the material’s defects, which boosts the transistor’s performance.The material’s unique magnetic properties also allow for transistors with built-in memory, which would simplify circuit design and unlock new applications for high-performance electronics.“People have known about magnets for thousands of years, but there are very limited ways to incorporate magnetism into electronics. We have shown a new way to efficiently utilize magnetism that opens up a lot of possibilities for future applications and research,” says Chung-Tao Chou, an MIT graduate student in the departments of Electrical Engineering and Computer Science (EECS) and Physics, and co-lead author of a paper on this advance.Chou is joined on the paper by co-lead author Eugene Park, a graduate student in the Department of Materials Science and Engineering (DMSE); Julian Klein, a DMSE research scientist; Josep Ingla-Aynes, a postdoc in the MIT Plasma Science and Fusion Center; Jagadeesh S. Moodera, a senior research scientist in the Department of Physics; and senior authors Frances Ross, TDK Professor in DMSE; and Luqiao Liu, an associate professor in EECS, and a member of the Research Laboratory of Electronics; as well as others at the University of Chemistry and Technology in Prague. The paper appears today in Physical Review Letters.Overcoming the limitsIn an electronic device, silicon semiconductor transistors act like tiny light switches that turn a circuit on and off, or amplify weak signals in a communication system. They do this using a small input voltage.But a fundamental physical limit of silicon semiconductors prevents a transistor from operating below a certain voltage, which hinders its energy efficiency.To make more efficient electronics, researchers have spent decades working toward magnetic transistors that utilize electron spin to control the flow of electricity. Electron spin is a fundamental property that enables electrons to behave like tiny magnets.So far, scientists have mostly been limited to using certain magnetic materials. These lack the favorable electronic properties of semiconductors, constraining device performance.“In this work, we combine magnetism and semiconductor physics to realize useful spintronic devices,” Liu says.The researchers replace the silicon in the surface layer of a transistor with chromium sulfur bromide, a two-dimensional material that acts as a magnetic semiconductor.Due to the material’s structure, researchers can switch between two magnetic states very cleanly. This makes it ideal for use in a transistor that smoothly switches between “on” and “off.”“One of the biggest challenges we faced was finding the right material. We tried many other materials that didn’t work,” Chou says.They discovered that changing these magnetic states modifies the material’s electronic properties, enabling low-energy operation. And unlike many other 2D materials, chromium sulfur bromide remains stable in air.To make a transistor, the researchers pattern electrodes onto a silicon substrate, then carefully align and transfer the 2D material on top. They use tape to pick up a tiny piece of material, only a few tens of nanometers thick, and place it onto the substrate.“A lot of researchers will use solvents or glue to do the transfer, but transistors require a very clean surface. We eliminate all those risks by simplifying this step,” Chou says.Leveraging magnetismThis lack of contamination enables their device to outperform existing magnetic transistors. Most others can only create a weak magnetic effect, changing the flow of current by a few percent or less. Their new transistor can switch or amplify the electric current by a factor of 10.They use an external magnetic field to change the magnetic state of the material, switching the transistor using significantly less energy than would usually be required.The material also allows them to control the magnetic states with electric current. This is important because engineers cannot apply magnetic fields to individual transistors in an electronic device. They need to control each one electrically.The material’s magnetic properties could also enable transistors with built-in memory, simplifying the design of logic or memory circuits.A typical memory device has a magnetic cell to store information and a transistor to read it out. Their method can combine both into one magnetic transistor.“Now, not only are transistors turning on and off, they are also remembering information. And because we can switch the transistor with greater magnitude, the signal is much stronger so we can read out the information faster, and in a much more reliable way,” Liu says.Building on this demonstration, the researchers plan to further study the use of electrical current to control the device. They are also working to make their method scalable so they can fabricate arrays of transistors.This research was supported, in part, by the Semiconductor Research Corporation, the U.S. Defense Advanced Research Projects Agency (DARPA), the U.S. National Science Foundation (NSF), the U.S. Department of Energy, the U.S. Army Research Office, and the Czech Ministry of Education, Youth, and Sports. The work was partially carried out at the MIT.nano facilities. More

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      in Environment

      MIT geologists discover where energy goes during an earthquake

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      The ground-shaking that an earthquake generates is only a fraction of the total energy that a quake releases. A quake can also generate a flash of heat, along with a domino-like fracturing of underground rocks. But exactly how much energy goes into each of these three processes is exceedingly difficult, if not impossible, to measure in the field.Now MIT geologists have traced the energy that is released by “lab quakes” — miniature analogs of natural earthquakes that are carefully triggered in a controlled laboratory setting. For the first time, they have quantified the complete energy budget of such quakes, in terms of the fraction of energy that goes into heat, shaking, and fracturing.They found that only about 10 percent of a lab quake’s energy causes physical shaking. An even smaller fraction — less than 1 percent — goes into breaking up rock and creating new surfaces. The overwhelming portion of a quake’s energy — on average 80 percent — goes into heating up the immediate region around a quake’s epicenter. In fact, the researchers observed that a lab quake can produce a temperature spike hot enough to melt surrounding material and turn it briefly into liquid melt.The geologists also found that a quake’s energy budget depends on a region’s deformation history — the degree to which rocks have been shifted and disturbed by previous tectonic motions. The fractions of quake energy that produce heat, shaking, and rock fracturing can shift depending on what the region has experienced in the past.“The deformation history — essentially what the rock remembers — really influences how destructive an earthquake could be,” says Daniel Ortega-Arroyo, a graduate student in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “That history affects a lot of the material properties in the rock, and it dictates to some degree how it is going to slip.”The team’s lab quakes are a simplified analog of what occurs during a natural earthquake. Down the road, their results could help seismologists predict the likelihood of earthquakes in regions that are prone to seismic events. For instance, if scientists have an idea of how much shaking a quake generated in the past, they might be able to estimate the degree to which the quake’s energy also affected rocks deep underground by melting or breaking them apart. This in turn could reveal how much more or less vulnerable the region is to future quakes.“We could never reproduce the complexity of the Earth, so we have to isolate the physics of what is happening, in these lab quakes,” says Matěj Peč, associate professor of geophysics at MIT. “We hope to understand these processes and try to extrapolate them to nature.”Peč (pronounced “Peck”) and Ortega-Arroyo reported their results on Aug. 28 in the journal AGU Advances. Their MIT co-authors are Hoagy O’Ghaffari and Camilla Cattania, along with Zheng Gong and Roger Fu at Harvard University and Markus Ohl and Oliver Plümper at Utrecht University in the Netherlands.Under the surfaceEarthquakes are driven by energy that is stored up in rocks over millions of years. As tectonic plates slowly grind against each other, stress accumulates through the crust. When rocks are pushed past their material strength, they can suddenly slip along a narrow zone, creating a geologic fault. As rocks slip on either side of the fault, they produce seismic waves that ripple outward and upward.We perceive an earthquake’s energy mainly in the form of ground shaking, which can be measured using seismometers and other ground-based instruments. But the other two major forms of a quake’s energy — heat and underground fracturing — are largely inaccessible with current technologies.“Unlike the weather, where we can see daily patterns and measure a number of pertinent variables, it’s very hard to do that very deep in the Earth,” Ortega-Arroyo says. “We don’t know what’s happening to the rocks themselves, and the timescales over which earthquakes repeat within a fault zone are on the century-to-millenia timescales, making any sort of actionable forecast challenging.”To get an idea of how an earthquake’s energy is partitioned, and how that energy budget might affect a region’s seismic risk, he and Peč went into the lab. Over the last seven years, Peč’s group at MIT has developed methods and instrumentation to simulate seismic events, at the microscale, in an effort to understand how earthquakes at the macroscale may play out.“We are focusing on what’s happening on a really small scale, where we can control many aspects of failure and try to understand it before we can do any scaling to nature,” Ortega-Arroyo says.MicroshakesFor their new study, the team generated miniature lab quakes that simulate a seismic slipping of rocks along a fault zone. They worked with small samples of granite, which are representative of rocks in the seismogenic layer — the geologic region in the continental crust where earthquakes typically originate. They ground up the granite into a fine powder and mixed the crushed granite with a much finer powder of magnetic particles, which they used as a sort of internal temperature gauge. (A particle’s magnetic field strength will change in response to a fluctuation in temperature.)The researchers placed samples of the powdered granite — each about 10 square millimeters and 1 millimeter thin — between two small pistons and wrapped the ensemble in a gold jacket. They then applied a strong magnetic field to orient the powder’s magnetic particles in the same initial direction and to the same field strength. They reasoned that any change in the particles’ orientation and field strength afterward should be a sign of how much heat that region experienced as a result of any seismic event.Once samples were prepared, the team placed them one at a time into a custom-built apparatus that the researchers tuned to apply steadily increasing pressure, similar to the pressures that rocks experience in the Earth’s seismogenic layer, about 10 to 20 kilometers below the surface. They used custom-made piezoelectric sensors, developed by co-author O’Ghaffari, which they attached to either end of a sample to measure any shaking that occurred as they increased the stress on the sample.They observed that at certain stresses, some samples slipped, producing a microscale seismic event similar to an earthquake. By analyzing the magnetic particles in the samples after the fact, they obtained an estimate of how much each sample was temporarily heated — a method developed in collaboration with Roger Fu’s lab at Harvard University. They also estimated the amount of shaking each sample experienced, using measurements from the piezoelectric sensor and numerical models. The researchers also examined each sample under the microscope, at different magnifications, to assess how the size of the granite grains changed — whether and how many grains broke into smaller pieces, for instance.From all these measurements, the team was able to estimate each lab quake’s energy budget. On average, they found that about 80 percent of a quake’s energy goes into heat, while 10 percent generates shaking, and less than 1 percent goes into rock fracturing, or creating new, smaller particle surfaces. “In some instances we saw that, close to the fault, the sample went from room temperature to 1,200 degrees Celsius in a matter of microseconds, and then immediately cooled down once the motion stopped,” Ortega-Arroyo says. “And in one sample, we saw the fault move by about 100 microns, which implies slip velocities essentially about 10 meters per second. It moves very fast, though it doesn’t last very long.”The researchers suspect that similar processes play out in actual, kilometer-scale quakes.“Our experiments offer an integrated approach that provides one of the most complete views of the physics of earthquake-like ruptures in rocks to date,” Peč says. “This will provide clues on how to improve our current earthquake models and natural hazard mitigation.”This research was supported, in part, by the National Science Foundation. More

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      in Environment

      Simpler models can outperform deep learning at climate prediction

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      Environmental scientists are increasingly using enormous artificial intelligence models to make predictions about changes in weather and climate, but a new study by MIT researchers shows that bigger models are not always better.The team demonstrates that, in certain climate scenarios, much simpler, physics-based models can generate more accurate predictions than state-of-the-art deep-learning models.Their analysis also reveals that a benchmarking technique commonly used to evaluate machine-learning techniques for climate predictions can be distorted by natural variations in the data, like fluctuations in weather patterns. This could lead someone to believe a deep-learning model makes more accurate predictions when that is not the case.The researchers developed a more robust way of evaluating these techniques, which shows that, while simple models are more accurate when estimating regional surface temperatures, deep-learning approaches can be the best choice for estimating local rainfall.They used these results to enhance a simulation tool known as a climate emulator, which can rapidly simulate the effect of human activities onto a future climate.The researchers see their work as a “cautionary tale” about the risk of deploying large AI models for climate science. While deep-learning models have shown incredible success in domains such as natural language, climate science contains a proven set of physical laws and approximations, and the challenge becomes how to incorporate those into AI models.“We are trying to develop models that are going to be useful and relevant for the kinds of things that decision-makers need going forward when making climate policy choices. While it might be attractive to use the latest, big-picture machine-learning model on a climate problem, what this study shows is that stepping back and really thinking about the problem fundamentals is important and useful,” says study senior author Noelle Selin, a professor in the MIT Institute for Data, Systems, and Society (IDSS) and the Department of Earth, Atmospheric and Planetary Sciences (EAPS).Selin’s co-authors are lead author Björn Lütjens, a former EAPS postdoc who is now a research scientist at IBM Research; senior author Raffaele Ferrari, the Cecil and Ida Green Professor of Oceanography in EAPS and co-director of the Lorenz Center; and Duncan Watson-Parris, assistant professor at the University of California at San Diego. Selin and Ferrari are also co-principal investigators of the Bringing Computation to the Climate Challenge project, out of which this research emerged. The paper appears today in the Journal of Advances in Modeling Earth Systems.Comparing emulatorsBecause the Earth’s climate is so complex, running a state-of-the-art climate model to predict how pollution levels will impact environmental factors like temperature can take weeks on the world’s most powerful supercomputers.Scientists often create climate emulators, simpler approximations of a state-of-the art climate model, which are faster and more accessible. A policymaker could use a climate emulator to see how alternative assumptions on greenhouse gas emissions would affect future temperatures, helping them develop regulations.But an emulator isn’t very useful if it makes inaccurate predictions about the local impacts of climate change. While deep learning has become increasingly popular for emulation, few studies have explored whether these models perform better than tried-and-true approaches.The MIT researchers performed such a study. They compared a traditional technique called linear pattern scaling (LPS) with a deep-learning model using a common benchmark dataset for evaluating climate emulators.Their results showed that LPS outperformed deep-learning models on predicting nearly all parameters they tested, including temperature and precipitation.“Large AI methods are very appealing to scientists, but they rarely solve a completely new problem, so implementing an existing solution first is necessary to find out whether the complex machine-learning approach actually improves upon it,” says Lütjens.Some initial results seemed to fly in the face of the researchers’ domain knowledge. The powerful deep-learning model should have been more accurate when making predictions about precipitation, since those data don’t follow a linear pattern.They found that the high amount of natural variability in climate model runs can cause the deep learning model to perform poorly on unpredictable long-term oscillations, like El Niño/La Niña. This skews the benchmarking scores in favor of LPS, which averages out those oscillations.Constructing a new evaluationFrom there, the researchers constructed a new evaluation with more data that address natural climate variability. With this new evaluation, the deep-learning model performed slightly better than LPS for local precipitation, but LPS was still more accurate for temperature predictions.“It is important to use the modeling tool that is right for the problem, but in order to do that you also have to set up the problem the right way in the first place,” Selin says.Based on these results, the researchers incorporated LPS into a climate emulation platform to predict local temperature changes in different emission scenarios.“We are not advocating that LPS should always be the goal. It still has limitations. For instance, LPS doesn’t predict variability or extreme weather events,” Ferrari adds.Rather, they hope their results emphasize the need to develop better benchmarking techniques, which could provide a fuller picture of which climate emulation technique is best suited for a particular situation.“With an improved climate emulation benchmark, we could use more complex machine-learning methods to explore problems that are currently very hard to address, like the impacts of aerosols or estimations of extreme precipitation,” Lütjens says.Ultimately, more accurate benchmarking techniques will help ensure policymakers are making decisions based on the best available information.The researchers hope others build on their analysis, perhaps by studying additional improvements to climate emulation methods and benchmarks. Such research could explore impact-oriented metrics like drought indicators and wildfire risks, or new variables like regional wind speeds.This research is funded, in part, by Schmidt Sciences, LLC, and is part of the MIT Climate Grand Challenges team for “Bringing Computation to the Climate Challenge.” More

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      in Security

      MIT chemists boost the efficiency of a key enzyme in photosynthesis

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      During photosynthesis, an enzyme called rubisco catalyzes a key reaction — the incorporation of carbon dioxide into organic compounds to create sugars. However, rubisco, which is believed to be the most abundant enzyme on Earth, is very inefficient compared to the other enzymes involved in photosynthesis.MIT chemists have now shown that they can greatly enhance a version of rubisco found in bacteria from a low-oxygen environment. Using a process known as directed evolution, they identified mutations that could boost rubisco’s catalytic efficiency by up to 25 percent.The researchers now plan to apply their technique to forms of rubisco that could be used in plants to help boost their rates of photosynthesis, which could potentially improve crop yields.“This is, I think, a compelling demonstration of successful improvement of a rubisco’s enzymatic properties, holding out a lot of hope for engineering other forms of rubisco,” says Matthew Shoulders, the Class of 1942 Professor of Chemistry at MIT.Shoulders and Robert Wilson, a research scientist in the Department of Chemistry, are the senior authors of the new study, which appears this week in the Proceedings of the National Academy of Sciences. MIT graduate student Julie McDonald is the paper’s lead author.Evolution of efficiencyWhen plants or photosynthetic bacteria absorb energy from the sun, they first convert it into energy-storing molecules such as ATP. In the next phase of photosynthesis, cells use that energy to transform a molecule known as ribulose bisphosphate into glucose, which requires several additional reactions. Rubisco catalyzes the first of those reactions, known as carboxylation. During that reaction, carbon from CO2 is added to ribulose bisphosphate.Compared to the other enzymes involved in photosynthesis, rubisco is very slow, catalyzing only one to 10 reactions per second. Additionally, rubisco can also interact with oxygen, leading to a competing reaction that incorporates oxygen instead of carbon — a process that wastes some of the energy absorbed from sunlight.“For protein engineers, that’s a really attractive set of problems because those traits seem like things that you could hopefully make better by making changes to the enzyme’s amino acid sequence,” McDonald says.Previous research has led to improvement in rubisco’s stability and solubility, which resulted in small gains in enzyme efficiency. Most of those studies used directed evolution — a technique in which a naturally occurring protein is randomly mutated and then screened for the emergence of new, desirable features.This process is usually done using error-prone PCR, a technique that first generates mutations in vitro (outside of the cell), typically introducing only one or two mutations in the target gene. In past studies on rubisco, this library of mutations was then introduced into bacteria that grow at a rate relative to rubisco activity. Limitations in error-prone PCR and in the efficiency of introducing new genes restrict the total number of mutations that can be generated and screened using this approach. Manual mutagenesis and selection steps also add more time to the process over multiple rounds of evolution.The MIT team instead used a newer mutagenesis technique that the Shoulders Lab previously developed, called MutaT7. This technique allows the researchers to perform both mutagenesis and screening in living cells, which dramatically speeds up the process. Their technique also enables them to mutate the target gene at a higher rate.“Our continuous directed evolution technique allows you to look at a lot more mutations in the enzyme than has been done in the past,” McDonald says.Better rubiscoFor this study, the researchers began with a version of rubisco, isolated from a family of semi-anaerobic bacteria known as Gallionellaceae, that is one of the fastest rubisco found in nature. During the directed evolution experiments, which were conducted in E. coli, the researchers kept the microbes in an environment with atmospheric levels of oxygen, creating evolutionary pressure to adapt to oxygen.After six rounds of directed evolution, the researchers identified three different mutations that improved the rubisco’s resistance to oxygen. Each of these mutations are located near the enzyme’s active site (where it performs carboxylation or oxygenation). The researchers believe that these mutations improve the enzyme’s ability to preferentially interact with carbon dioxide over oxygen, which leads to an overall increase in carboxylation efficiency.“The underlying question here is: Can you alter and improve the kinetic properties of rubisco to operate better in environments where you want it to operate better?” Shoulders says. “What changed through the directed evolution process was that rubisco began to like to react with oxygen less. That allows this rubisco to function well in an oxygen-rich environment, where normally it would constantly get distracted and react with oxygen, which you don’t want it to do.”In ongoing work, the researchers are applying this approach to other forms of rubisco, including rubisco from plants. Plants are believed to lose about 30 percent of the energy from the sunlight they absorb through a process called photorespiration, which occurs when rubisco acts on oxygen instead of carbon dioxide.“This really opens the door to a lot of exciting new research, and it’s a step beyond the types of engineering that have dominated rubisco engineering in the past,” Wilson says. “There are definite benefits to agricultural productivity that could be leveraged through a better rubisco.”The research was funded, in part, by the National Science Foundation, the National Institutes of Health, an Abdul Latif Jameel Water and Food Systems Lab Grand Challenge grant, and a Martin Family Society Fellowship for Sustainability. More