Tuesday, November 22nd, 2016

Time	Event
12:00a	Forging ahead on climate action Last year, participants in the Paris Agreement on climate change expressed the shared global objective of limiting temperature rise, with each party to the agreement laying out its intended national contributions to addressing climate change. At this year’s UN Climate Change Conference (COP22) in Marrakech, Morocco, as the world wondered what a change in administration could mean for U.S. climate policy and — by extension — the momentum for the Paris Agreement, national and civil society leaders repeatedly expressed their commitment to upholding and advancing implementation of the agreement. For MIT, the imperative is as clear as ever. “The Paris Agreement motivated us immensely,” said Maria Zuber, MIT's vice president for research, at a series of conversations hosted by Emerson Collective in Marrakech. “MIT strongly supports the agreement. Collectively, on our campus, we said it is a great starting point — but it’s not enough,” she said. Zuber spoke with Michael Crow, president of Arizona State University, and Dan Arvizu, Emerson Collective’s chief technology officer and STEM evangelist, on the role of academic research and innovation in meeting global greenhouse gas reduction targets. She went on to describe the Institute’s efforts to conduct research and develop partnerships that foster climate solutions. These solutions include nature-focused approaches. “Nature-based solutions can play an important part in addressing climate change. Not only can we learn from how natural systems self-regulate, but we can apply that knowledge to designing new technologies and courses of action,” said John Fernández, director of MIT's Environmental Solutions Initiative and a professor of architecture. His initiative is currently exploring partnerships around nature-based climate solutions that protect ecosystems. At the same event, MIT Media Lab Director Joi Ito discussed the importance of designing systems to solve for multiple problems — such as reducing carbon emissions while also improving quality of life and caring for the environment. “When you think of a complex system like the environment or a city, how do you design for everything in the system so that it’s optimized not just for the one player that has economic value, but for the entire system? That’s the kind of design we need to figure out how to do,” he said, adding: “The people participating day-to-day in the system can be the designers. It’s about bringing science directly into the community and having the community participate in the science.” Robert Stoner, deputy director of the MIT Energy Initiative (MITEI), expanded on this idea in a breakout discussion on citizen science and education. “The democratization of data with the availability of low-cost measurement technology and access to the Internet creates new opportunities for nonscientists to participate in creating knowledge and using it to improve the world. But [it also creates] potential for that data to be misinterpreted or misused in civil discourse — underscoring the need for scientists to be involved ‘on the playing field’ as interpreters in an ethical and responsible manner,” said Stoner, who is also the director of the Tata Center for Technology and Design. Crowdsourcing climate solutions To empower individuals to contribute to climate solutions while employing scientific rigor, MIT’s Climate CoLab has developed a crowdsourcing platform for people around the world to collaborate on creating plans for addressing climate change. At a COP22 side event with Climate Interactive and the Abibimman Foundation, Climate CoLab project manager Laur Hesse Fisher described the online platform and contests, in which participants devise individual climate policies and actions, and integrated national and global plans. Scientific experts analyze and judge the proposals in terms of projects’ feasibility and potential impacts among other criteria. The winners use prize money to help scale their ideas. Fisher encouraged audience members to submit proposals for a contest open through February with the United Nations Secretary-General’s Climate Resilience Initiative: Anticipate, Absorb, Reshape (A2R). “We’re running a contest to get your ideas and your projects on how the most vulnerable countries can anticipate the climate hazards that they’re going to face,” she said. “We welcome you to submit your idea so that you can be part of this process.”  Fisher also spoke at an event with the Cities Climate Finance Leadership Alliance to showcase and discuss existing initiatives and practical examples of approaches intended to accelerate climate action at the urban level, and she held several other events to introduce people to Climate CoLab’s platform. "Climate CoLab shows that new technologies can make new things possible, and that’s what we do at MIT,” said Fisher. “But it’s not only more efficient solar panels or carbon capture technologies — it’s also new ways that the world can work together.” Sharing interactive climate tools in Africa Ahead of and throughout COP22, John Sterman, a professor of management at the MIT Sloan School of Management, and Climate Interactive team members have worked to bring their interactive climate policy models and tools to Africa. They have conducted workshops on their jointly developed “World Climate” role play throughout Africa and around the world — including sessions with Moroccan business leaders and university students, staff, and faculty. “We’re enabling local scholars, educators, and members of civil society to help their communities learn for themselves about the international climate negotiations, data modeling, and the urgency of emissions reductions for all nations,” said Sterman. MIT and Climate Interactive have also created new tools to support “climate smart agriculture” in Africa, led by Climate Interactive’s Travis Franck SM ’05 PhD ’09, who is also an MIT research affiliate. “Our prototype interactive system dynamics model considers how countries can meet two critical goals: expanding food production to support their growing populations and cutting the greenhouse emissions from the agricultural sector,” said Sterman. He and Franck shared this work in several side events at COP22. Analyzing nations’ climate progress and choices Graduate students Arun Singh and Michael Davidson came to Marrakech to advance their international climate research and keep abreast of real-time developments in climate policy. Davidson, who first attended the international climate talks in 2010, researches China’s climate and energy policies related to renewable energy and the electric grid as a PhD candidate with the Institute for Data, Systems, and Society (IDSS) and a research associate with the Joint Program on the Science and Policy of Global Change. He arrived in Marrakech just before the U.S. election and witnessed uncertainties arising from the outcome globally and around U.S.-China relations, which had warmed leading up to the Paris Agreement last year, with jointly announced climate commitments that were seen as crucial to the adoption of the agreement. “There are many reasons why it's in the best interests of the U.S. not to withdraw, but now, the big question is, if the U.S. does leave the agreement, who’s going to take up the mantle and drive the implementation process forward? There is a lot of interest in seeing China — but also EU and others — step forward, helping to fundamentally shape the agreement without U.S. input or interests at its center,” said Davidson. He is also examining how the agreement's provisions on tracking countries’ progress toward meeting collective climate goals will take shape, and is among those helping to ensure that it will include robust scientific assessments, working with advisor Valerie Karplus and Henry Jacoby, professors at the MIT Sloan School. Singh, a master’s degree student with IDSS and a fellow with the Tata Center for Technology and Design, is developing an energy-economic model to help inform India’s climate policies and technology choices. He shared his research at a side event and conducted interviews related to his work as a Tata Fellow and research associate of the Joint Program with advisors Karplus and principal research scientist Niven Winchester. During COP22, the U.S., China, and Mexico announced their 2050 greenhouse gas emissions targets, with the U.S. and Canada each pledging to reduce emissions 80 percent from 2005 levels by 2050, and Mexico pledging to reduce emissions 50 percent from 2000 levels by 2050. The U.S. released its plan in a new report, the United States Mid-Century Strategy for Deep Decarbonization, which cited research by Jessika Trancik, an associate professor of energy studies with IDSS, on the “virtuous cycle” of continued clean energy technology development and deployment “in which ambition drives down costs, in turn eliciting greater ambition.” In an analysis of the three nations’ plans, Sterman said, “Our relentlessly shrinking carbon budget means all nations of the world must offer earlier and deeper cuts than they pledged in Paris, and continue to cut emissions through the end of the century. These midcentury strategies should inspire other nations to be even more ambitious. Warming cannot be limited to ‘well below’ 2 C without stronger midcentury commitments from all other nations.” Committing to continued action Speaking with news network France24, Sterman reflected on the overarching sentiments at COP22 in the wake of the U.S. election: “The agenda has changed, but what is interesting is that a large number of the parties — the nations here — are asserting that they will continue to reduce their emissions regardless of what the United States may or may not do under the new administration,” he said. “And the civil society groups that are here, representing every aspect of society in the United States and around the world, are committed to redoubling their efforts to build grassroots support for climate action at the community, municipal, and state level.” At MIT, across the Institute, community members are prepared to keep accelerating climate action in keeping with the Plan for Action on Climate Change. As Zuber said at the Emerson Collective event, “We can’t just talk about this. We have to lead by example.” (Comment on this)
12:00a	Biomarker could help guide cancer therapy, avoid drug resistance MIT biologists have identified a new biomarker that can reveal whether patients with a particularly aggressive type of breast cancer will be helped by paclitaxel (commercially known as Taxol), one of the drugs most commonly used to treat this cancer. The findings could offer doctors a new way to choose drugs for this type of breast cancer, known as triple-negative because it lacks the three most common breast cancer markers: estrogen receptor, progesterone receptor, and Her2 protein. The biomarker, a protein called Mena, has previously been shown to help cancer cells spread through the body. The researchers also showed that combining paclitaxel with another drug that interferes with Mena’s effects can kill the cells much more effectively than paclitaxel alone. “Drugs that target that pathway restore paclitaxel sensitivity to cells expressing Mena,” says Frank Gertler, an MIT professor of biology and a member of the Koch Institute for Integrative Cancer Research. “The study also suggests that during the course of treatment it might be worth monitoring the level of Mena. If the levels begin to increase, it might suggest that switching to another type of therapy could be useful.” Gertler is the senior author of the study, which appears in the journal Molecular Cancer Therapeutics. Madeleine Oudin, a Koch Institute postdoc, is the paper’s lead author. How cells survive The Mena protein is known to interact with a cell’s cytoskeleton in ways that help the cell to become mobile. Many cancer patients have an alternative form of the protein known as Mena invasive or MenaINV, which helps cancer cells to spread from their original location through a process known as metastasis. Gertler’s research group has previously found that breast cancer patients who have high levels of the protein’s invasive form tend to have more metastasis and lower survival rates. The researchers wondered if Mena might also play a role in cancer cell resistance to chemotherapy. Between 30 to 70 percent of triple-negative breast cancer patients respond well to chemotherapy, but the disease reappears within six to 10 months, on average. “We know we have good drugs that can kill a lot of cancers, but some people don’t respond to them, and some people do respond but only for a short amount of time,” Oudin says. They tested several different chemotherapy drugs on triple-negative breast cancer cells with varying levels of Mena, and found that those cells with the highest Mena levels were resistant to paclitaxel. However, Mena levels did not affect sensitivity to two other commonly used chemotherapy drugs, doxorubicin and cisplatin. Paclitaxel, which is also used to treat ovarian cancer, works by interfering with microtubules — small tubular proteins that make up the cell’s cytoskeleton and help with cell division. Microtubules can be either dynamic or stable, and the dynamic version is necessary for cell division. Paclitaxel stabilizes the microtubules, interfering with cell division and killing the cells. After giving paclitaxel to mice with metastatic triple-negative tumors, the researchers found that tumors with the highest levels of Mena showed the worst response: The drug did not slow growth of either the original tumors or metastases. This effect was the same whether the tumors expressed the invasive form of Mena or the original version. The researchers also showed that cancer cells with high Mena levels had more dynamic microtubules than cells with low Mena levels. This increase in dynamic microtubules makes it easier for the cells to divide and allows them to resist the effects of paclitaxel. Countering resistance Previous studies have shown that paclitaxel treatment also affects a cellular pathway known as ERK signaling, which is often overactive in cancer cells and drives cell proliferation. Paclitaxel treatment turns on this pathway, which helps cancer cells to survive the treatment, but if an inhibitor of ERK signaling is given at the same time, the treatment is more successful. In the Molecular Cancer Therapeutics study, the MIT team tried the paclitaxel-ERK pathway inhibitor combination in breast cancer cells with high levels of Mena and found that it killed cells much more effectively than paclitaxel alone. Clinical trials are already underway to test this combination of drugs in breast cancer. “Our work would suggest that for a certain subset of patients that have high levels of Mena, that could be an efficient combination to try,” Oudin says. The findings could also help doctors choose treatments for patients based on the levels of Mena in their tumors. To pursue that possibility, the researchers now hope to do studies with human tumor samples to see if they show the same relationship between Mena levels, paclitaxel sensitivity, and patient outcome. This work may be done in collaboration with MetaStat, a company that Gertler and others founded to develop diagnostic tests based on Mena and other biomarkers. “The hope is it may also provide more information on therapeutic choice and potentially spare some patients treatment with a chemotherapy that is likely to be less effective,” Gertler says. “Triple-negative breast cancer patients don’t have many treatment options,” says Bruce Zetter, a professor of cancer biology and surgery at Harvard Medical School. “If this work can help identify patients most likely to respond to Taxol and encourage greater use of the combination of MEK inhibitors and Taxol, that could potentially lead to greater survival of patients with that disease.” The researchers also hope to uncover more of the mechanism of how Mena affects microtubules, and to see if the same interaction plays a role in drug resistance in other types of cancer, such as ovarian cancer. The research was funded by the Department of Defense Breast Cancer Research Program, ENS-Cachan, the Ludwig Center at MIT, the National Institutes of Health and National Cancer Institute, the Koch Institute Frontier Research Program through the Kathy and Curt Marble Cancer Research Fund, and the Koch Institute National Cancer Institute core grant. (Comment on this)
12:00a	Toward X-ray movies Ultrashort bursts of electrons have several important applications in scientific imaging, but producing them has typically required a costly, power-hungry apparatus about the size of a car. In the journal Optica, researchers at MIT, the German Synchrotron, and the University of Hamburg in Germany describe a new technique for generating electron bursts, which could be the basis of a shoebox-sized device that consumes only a fraction as much power as its predecessors. Ultrashort electron beams are used to directly gather information about materials that are undergoing chemical reactions or changes of physical state. But after being fired down a particle accelerator a half a mile long, they’re also used to produce ultrashort X-rays. Last year, in Nature Communications, the same group of MIT and Hamburg researchers reported the prototype of a small “linear accelerator” that could serve the same purpose as the much larger and more expensive particle accelerator. That technology, together with a higher-energy version of the new “electron gun,” could bring the imaging power of ultrashort X-ray pulses to academic and industry labs. Indeed, while the electron bursts reported in the new paper have a duration measured in hundreds of femtoseconds, or quadrillionths of a second (which is about what the best existing electron guns can manage), the researchers’ approach has the potential to lower their duration to a single femtosecond. An electron burst of a single femtosecond could generate attosecond X-ray pulses, which would enable real-time imaging of cellular machinery in action. “We’re building a tool for the chemists, physicists, and biologists who use X-ray light sources or the electron beams directly to do their research,” says Ronny Huang, an MIT PhD student in electrical engineering and first author on the new paper. “Because these electron beams are so short, they allow you to kind of freeze the motion of electrons inside molecules as the molecules are undergoing a chemical reaction. A femtosecond X-ray light source requires more hardware, but it utilizes electron guns.” In particular, Huang explains, with a technique called electron diffraction imaging, physicists and chemists use ultrashort bursts of electrons to investigate phase changes in materials, such as the transition from an electrically conductive to a nonconductive state, and the creation and dissolution of bonds between molecules in chemical reactions. Ultrashort X-ray pulses have the same advantages that ordinary X-rays do: They penetrate more deeply into thicker materials. The current method for producing ultrashort X-rays involves sending electron bursts from a car-sized electron gun through a billion-dollar, kilometer-long particle accelerator that increases their velocity. Then they pass between two rows of magnets — known as an “undulator” — that converts them to X-rays. In the paper published last year — on which Huang was a coauthor — the MIT-Hamburg group, together with colleagues from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg and the University of Toronto, described a new approach to accelerating electrons that could shrink particle accelerators to tabletop size. “This is supposed to complement that,” Huang says, about the new study. Franz Kärtner, who was a professor of electrical engineering at MIT for 10 years before moving to the German Synchrotron and the University of Hamburg in 2011, led the project. Kärtner remains a principal investigator at MIT’s Research Laboratory of Electronics and is Huang’s thesis advisor. He and Huang are joined on the new paper by eight colleagues from both MIT and Hamburg. Subwavelength confinement The researchers’ new electron gun is a variation on a device called an RF gun. But where the RF gun uses radio frequency (RF) radiation to accelerate electrons, the new device uses terahertz radiation, the band of electromagnetic radiation between microwaves and visible light. The researchers’ device, which is about the size of a matchbox, consists of two copper plates that, at their centers, are only 75 micrometers apart. Each plate has two bends in it, so that it looks rather like a trifold letter that’s been opened and set on its side. The plates bend in opposite directions, so that they’re farthest apart — 6 millimeters — at their edges. At the center of one of the plates is a quartz slide on which is deposited a film of copper that, at its thinnest, is only 30 nanometers thick. A short burst of light from an ultraviolet laser strikes the film at its thinnest point, jarring loose electrons, which are emitted on the opposite side of the film. At the same time, a burst of terahertz radiation passes between the plates in a direction perpendicular to that of the laser. All electromagnetic radiation can be thought of as having electrical and magnetic components, which are perpendicular to each other. The terahertz radiation is polarized so that its electric component accelerates the electrons directly toward the second plate. The key to the system is that the tapering of the plates confines the terahertz radiation to an area — the 75-micrometer gap — that is narrower than its own wavelength. “That’s something special,” Huang says. “Typically, in optics, you can’t confine something to below a wavelength. But using this structure we were able to. Confining it increases the energy density, which increases the accelerating power.” Because of that increased accelerating power, the device can make do with terahertz beams whose power is much lower than that of the radio-frequency beams used in a typical RF gun. Moreover, the same laser can generate both the ultraviolet beam and, with a few additional optical components, the terahertz beam. According to James Rosenzweig, a professor of physics at the University of California at Los Angeles, that’s one of the most attractive aspects of the researchers’ system. “One of the main problems you have with ultrafast sources like this is timing jitter between, say, the laser and accelerating field, which produces all sorts of systematic effects that make it harder to do time-resolved electron diffraction,” Rosezweig says. “In the case of Kärtner’s device, the laser produces the terahertz and also produces the photoelectrons, so the jitter is highly suppressed. You could do pump-probe experiments where the laser is the driver and the electrons would be the probe, and they would be more successful than what you have right now. And of course it would be a very small-sized and modest-cost device. So it might turn out to be very important as far as that scenario goes.” The researchers’ work was funded by the U.S. Air Force Office of Scientific Research and by the European Research Council. Ronny Huang was supported by a National Defense Science and Engineering Graduate fellowship. (Comment on this)

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