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Study: Democracy fosters economic growth

Thu, 03/07/2019 - 12:00am

As long as democracy has existed, there have been democracy skeptics — from Plato warning of mass rule to contemporary critics claiming authoritarian regimes can fast-track economic programs.

But a new study co-authored by an MIT economist shows that when it comes to growth, democracy significantly increases development. Indeed, countries switching to democratic rule experience a 20 percent increase in GDP over a 25-year period, compared to what would have happened had they remained authoritarian states, the researchers report. 

“I don’t find it surprising that it should be a big effect, because this is a big event, and nondemocracies, dictatorships, are messed up in many dimensions,” says Daron Acemoglu, an MIT economist and co-author of the new paper about the study.

Overall, Acemoglu notes, democracies employ broad-based investment, especially in health and human capital, which is lacking in authoritarian states. 

“Many reforms that are growth-enhancing get rid of special favors that nondemocratic regimes have done for their cronies. Democracies are much more pro-reform,” he says.

The paper, “Democracy Does Cause Growth,” is published this month in the Journal of Political Economy. The co-authors are Acemoglu, who is the Elizabeth and James Killian Professor of Economics at MIT; Suresh Naidu, an associate professor of economics and international and public affairs at Columbia University; Pascual Restrepo, an assistant professor of economics at Boston University; and James Robinson, a political scientist and economist at the Harris School of Public Policy of the University of Chicago.

Study the “switchers”

Acemoglu and Robinson have worked together for nearly two decades on research involving the interplay of institutions, political systems, and economic growth. The current paper is one product of that research program.

To conduct the study, the researchers examined 184 countries in the period from 1960 to 2010. During that time, there were 122 democratizations of countries, as well as 71 cases in which countries moved from democracy to a nondemocratic type of government.

The study focuses precisely on cases where countries have switched forms of rule. That’s because, in part, simply evaluating growth rates in democracies and nondemocracies at any one time does not yield useful comparisons. China may have grown more rapidly than France in recent decades, Acemoglu notes, but “France is a developed economy and China started at 1/20 the income per capita of France,” among many other differences.

Instead, Acemoglu and his colleagues aimed to “ask more squarely the counterfactual question” of how a country would have done with another form of government. To properly address that, he adds, “The obvious thing to do is focus on switchers” — that is, the countries changing from one mode of government to another. By closely tracking the growth trajectories of national economies in those circumstances, the researchers arrived at their conclusion.

They also found that countries that have democratized within the last 60 years have generally done so not at random moments, but at times of economic distress. That sheds light on the growth trajectories of democracies: They start off slowly while trying to rebound from economic misery. 

“Dictatorships collapse when they’re having economic problems,” Acemoglu says. “But now think about what that implies. It implies that you have a deep recession just before democratization, and you’re still going to have low GDP per capita for several years thereafter, because you’re trying to recover from this deep dive. So you’re going to see several years of low GDP during democracy.”

When that larger history is accounted for, Acemoglu says, “What we find is that [economies of democracies] slowly start picking up. So, in five or six years’ time they’re not appreciably richer than nondemocracies, but in a 10-to-15-year time horizon they become a little bit richer, and then by the end of 25 years, they are about 20 percent richer.”

Investing in people

As for the underlying mechanisms at work in the improved economies of democracies, Acemoglu notes that democratic governments tend to tax and invest more than authoritarian regimes do, particularly in medical care and education.

“Democracies … do a lot of things with their money, but two we can see are very robust are health and education,” Acemoglu says. The empirical data about those trends appear in a 2014 paper by the same four authors, “Democracy, Redistribution, and Inequality.”

For his part, Acemoglu emphasizes that the results include countries that have democratized but failed to enact much economic reform.

“That’s what’s remarkable about this result, by the way,” says Acemoglu. “There are some real basket-case democracies in our sample. … But despite that, I would say, the result is there.”

And despite the apparently sunny results of the paper, Acemoglu warns that there are no guarantees regarding a country’s political future. Democratic reforms do not help everyone in a society, and some people may prefer to let democracy wither for their own financial or political gain.

“It is possible to see this paper as an optimistic, good-news story [in which democracy] is a win-win,” says Acemoglu. “My reading is not a good-news story. … This paper is making the case that democracy is good for economic growth, but that doesn’t make it easy to sustain.” 

In the study’s sample of countries, Acemoglu adds, “We have almost twice as many democratizations as reversals of democracy, but the last 10 years, that number’s going the other way around. So democracy doesn’t have a walk in the park. It’s important to understand what democracy’s benefits are and where its fault lines are. I see this as part of that effort.”

Support for the research was provided by the Bradley Foundation and the Army Research Office Multidisciplinary University Research Initiative.

Learning to study a painful past

Thu, 03/07/2019 - 12:00am

If you ask MIT Associate Professor Lerna Ekmekçioğlu how she wound up in academia, she has a straightforward answer.

“I was born a historian,” Ekmekçioğlu says. “It was my destiny.”

That natural affinity for history has propelled her through the ranks of academia, as a pioneering scholar of Armenians in Turkey, including Armenian women. Her specialty is a complex topic involving a historical catastrophe: the role of women in society after the 1915 Armenian genocide.

More specifically, Ekmekçioğlu studies how Armenian women helped keep their community intact, even while transforming it by introducing feminist ideas. Her best-known book, “Recovering Armenia: The Limits of Belonging in Post-Genocide Turkey,” published in 2016 by Stanford University Press, reconstructs the life of the community of survivors, including its feminist voices, in the first decades after World War I.

Ekmekçioğlu’s basic interest in this subject is not hard to account for. She grew up in Istanbul, Turkey, as part of the small Armenian community remaining there over the decades. In this sense, Ekmekçioğlu really was born to be an Armenian historian. Understanding the world she grew up in meant understanding its past.

“I always had a curiosity about Armenian history,” Ekmekçioğlu notes. Still, it is a big leap from personal curiosity to a sustained career. And, as she recounts it, “I did not have any role models, really,” in academia, because there was so little work about what she wanted to study.

For this reason, Ekmekçioğlu’s career has two layers. One is her research and teaching — for which Ekmekçioğlu was awarded tenure at MIT last year.

The other is the extensive effort she has made to disseminate Armenian history to other students. Ekmekçioğlu is currently working on multiple projects at MIT to make Armenian historical materials widely available, and thus to create conditions in which today’s students and future researchers and historians can readily study the subject.

“I almost feel it as a responsibility,” Ekmekçioğlu says. “I see this as a public service.”

To see why this matters to Ekmekçioğlu, consider the circumstances in which she first started studying Armenian history and Armenian feminism, as an undergraduate at Bogazici University in Istanbul. The basic problem Ekmekçioğlu encountered: There weren’t established courses about Armenians, let alone Armenian women, at the university. Teaching Armenian history, to this day, remains a punishable crime in Turkey.

So Ekmekçioğlu and a few other students founded reading groups to study Armenian history and share information about written sources and materials that pertained to Armenian women. Together, a few of them entered a research paper competition, for all fields of history‚ and finished third.

That was enough to help Ekmekçioğlu and her friends gain more support from professors, who encouraged them to keep pursuing the subject. And they have: One of Ekmekçioğlu’s undergraduate friends was Melissa Bilal, now a faculty member at the American University of Armenia, in Yerevan, Armenia, with whom Ekmekçioğlu still collaborates on research and pedagogical projects.

As an undergraduate, Ekmekçioğlu also spent a year abroad at the University of Athens before graduating from Bogazici University in 2002. She then attended New York University as a graduate student, receiving her MA in 2004 and her PhD in 2010. After a year as a postdoc at the University of Michigan, Ekmekçioğlu joined the MIT faculty in 2011. Today she is the McMillan-Stewart Associate Professor of History at the Institute, and is affiliated with MIT’s Women’s and Gender Studies program and the Center for International Studies.

Ekmekçioğlu’s work examines a psychological and social strain at the heart of the lives of many Armenian women. After a shocking, traumatic human catastrophe, they were simultaneously trying to push their society forward, by developing new norms and rights for women, while also trying to hold their fractured community together by maintaining the cultural traditions of the past.

“By definition, they had to change,” Ekmekçioğlu says. “But that goal is in tension with maintaining Armenian tradition.”

In her book, Ekmekçioğlu’s work cleverly draws on written sources, such as an overlooked Armenian magazine called Hay Gin, to draw out the thoughts of the women she studies. More broadly, she has collaborated with Bilal to both publish and analyze an array of original-source documents about Armenian women, ranging in time from the 1860s to the 1960s.

When Ekmekçioğlu was still in graduate school, she and Bilal co-edited the first such volume on the subject, published in Istanbul in 2006 and translated as, “A Cry for Justice: Five Armenian Feminist Writers from the Ottoman Empire to the Turkish Republic.” Today, she and Bilal are working on a more comprehensive volume for publication, to be published in English as well as the original languages, with the working project title, “Feminism in Armenian: An Interpretive Anthology and Digital Archive.”

One component of this will be a volume combining original primary-source writings and scholarly essays, meant to make the ideas of Armenians a more easily accessible part of mainstream women’s history, and intended for classroom use.

Moreover, as the title suggests, Ekmekçioğlu and Bilal are working on a digital component of the project, which is intended to be the most comprehensive set of source materials on the subject yet in existence. She credits MIT as one of the institutions that has made this kind of project possible; she also recently received a Mellon Faculty Grant of the Center for Art, Science, and Technology, for a related public exhibition on the subject.

“There is a lot of curation involved in this,” Ekmekciouglu says. “I’ve had a lot of support at MIT.”

While Ekmekçioğlu is a leading historian of the early Turkish Republic in general,  most of her work has come with the clear purpose of calling attention to overlooked women who, in exceedingly difficult times, sought to keep their society alive.

“It’s only fair to those women who worked so hard, to do that,” Ekemkcioglu says.

Smoothing out the wrinkles in graphene

Wed, 03/06/2019 - 3:25pm

To protect graphene from performance-impairing wrinkles and contaminants that mar its surface during device fabrication, MIT researchers have turned to an everyday material: wax.

Graphene is an atom-thin material that holds promise for making next-generation electronics. Researchers are exploring possibilities for using the exotic material in circuits for flexible electronics and quantum computers, and in a variety of other devices.

But removing the fragile material from the substrate it’s grown on and transferring it to a new substrate is particularly challenging. Traditional methods encase the graphene in a polymer that protects against breakage but also introduces defects and particles onto graphene’s surface. These interrupt electrical flow and stifle performance.

In a paper published in Nature Communications, the researchers describe a fabrication technique that applies a wax coating to a graphene sheet and heats it up. Heat causes the wax to expand, which smooths out the graphene to reduce wrinkles. Moreover, the coating can be washed away without leaving behind much residue.

In experiments, the researchers’ wax-coated graphene performed four times better than graphene made with a traditional polymer-protecting layer. Performance, in this case, is measured in “electron mobility” — meaning how fast electrons move across a material’s surface — which is hindered by surface defects.

“Like waxing a floor, you can do the same type of coating on top of large-area graphene and use it as layer to pick up the graphene from a metal growth substrate and transfer it to any desired substrate,” says first author Wei Sun Leong, a postdoc in the Department of Electrical Engineering and Computer Science (EECS). “This technology is very useful, because it solves two problems simultaneously: the wrinkles and polymer residues.”

Co-first author Haozhe Wang, a PhD student in EECS, says using wax may sound like a natural solution, but it involved some thinking outside the box — or, more specifically, outside the laboratory: “As students, we restrict ourselves to sophisticated materials available in lab. Instead, in this work, we chose a material that commonly used in our daily life.”

Joining Leong and Wang on the paper are: Jing Kong and Tomas Palacios, both EECS professors; Markus Buehler, professor and head of the Department of Civil and Environmental Engineering (CEE); and six other graduate students, postdocs, and researchers from EECS, CEE, and the Department of Mechanical Engineering.

The “perfect” protector

To grow graphene over large areas, the 2-D material is typically grown on a commercial copper substrate. Then, it’s protected by a “sacrificial” polymer layer, typically polymethyl methacrylate (PMMA). The PMMA-coated graphene is placed in a vat of acidic solution until the copper is completely gone. The remaining PMMA-graphene is rinsed with water, then dried, and the PMMA layer is ultimately removed.

Wrinkles occur when water gets trapped between the graphene and the destination substrate, which PMMA doesn’t prevent. Moreover, PMMA comprises complex chains of oxygen, carbon, and hydrogen atoms that form strong bonds with graphene atoms. This leaves behind particles on the surface when it’s removed.

Researchers have tried modifying PMMA and other polymers to help reduce wrinkles and residue, but with minimal success. The MIT researchers instead searched for completely new materials — even once trying out commercial shrink wrap. “It was not that successful, but we did try,” Wang says, laughing.

After combing through materials science literature, the researchers landed on paraffin, the common whitish, translucent wax used for candles, polishes, and waterproof coatings, among other applications.

In simulations before testing, Buehler’s group, which studies the properties of materials, found no known reactions between paraffin and graphene. That’s due to paraffin’s very simple chemical structure. “Wax was so perfect for this sacrificial layer. It’s just simple carbon and hydrogen chains with low reactivity, compared to PMMA’s complex chemical structure that bonds to graphene,” Leong says.

Cleaner transfer

In their technique, the researchers first melted small pieces of the paraffin in an oven. Then, using a spin coater, a microfabrication machine that uses centrifugal force to uniformly spread material across a substrate, they dropped the paraffin solution onto a sheet of graphene grown on copper foil. This spread the paraffin into a protective layer, about 20 microns thick, across the graphene.

The researchers transferred the paraffin-coated graphene into a solution that removes the copper foil. The coated graphene was then relocated to a traditional water vat, which was heated to about 40 degrees Celsius. They used a silicon destination substrate to scoop up the graphene from underneath and baked in an oven set to the same temperature.

Because paraffin has a high thermal expansion coefficient, it expands quite a lot when heated. Under this heat increase, the paraffin expands and stretches the attached graphene underneath, effectively reducing wrinkles. Finally, the researchers used a different solution to wash away the paraffin, leaving a monolayer of graphene on the destination substrate.

In their paper, the researchers show microscopic images of a small area of the paraffin-coated and PMMA-coated graphene. Paraffin-coated graphene is almost fully clear of debris, whereas the PMMA-coated graphene looks heavily damaged, like a scratched window.

Because wax coating is already common in many manufacturing applications — such as applying a waterproof coating to a material — the researchers think their method could be readily adapted to real-world fabrication processes. Notably, the increase in temperature to melt the wax shouldn’t affect fabrication costs or efficiency, and the heating source could in the future be replaced with a light, the researchers say.

Next, the researchers aim to further minimize the wrinkles and contaminants left on the graphene and scaling up the system to larger sheets of graphene. They’re also working on applying the transfer technique to the fabrication processes of other 2-D materials.

“We will continue to grow the perfect large-area 2-D materials, so they come naturally without wrinkles,” Leong says.

Big issues on the table at the MIT Sloan Sports Analytics Conference

Wed, 03/06/2019 - 9:28am

NBA Commissioner Adam Silver listened to a question on stage Friday at the MIT Sloan Sports Analytics Conference, paused for a moment, and delivered a surprising assessment about some of his league’s star players.

“When I meet with them, what strikes me is that they’re truly unhappy,” Silver said. “This is not some, you know, show they’re putting on for the media.”

Without naming names, Silver went on to say that top professional basketball players were often “amazingly isolated” today, party because “they’re a product of social media” rather than old-fashioned team-building exercises.

Moreover, Silver added, players were being boxed into a quasiprofessional existence at young ages, given the presence of AAU teams, national camps, and recruiting ratings for young teenagers, along with a large social media spotlight for star college players.

“There’s never a period when you were nobody,” Silver said. “Especially the lottery-type picks” — that is, players eventually taken high in the NBA draft. When it comes to those players, Silver said, the major shoe companies “know that cohort when they’re 13.”

Those factors might explain why the NBA seems to have a large group of restless star players on its hands, several of whom seem to be publicly looking to switch teams soon. But Silver emphasized that the trends affecting the mental well-being of its players are hardly separate from what we see throughout society.

“I think we live in an age of anxiety,” Silver said.

Which might not seem to have a lot to do with sports analytics. Yet Silver’s comments do show how much MIT’s annual event has grown. The MIT Sloan Sports Analytics Conference — SSAC for short — now functions as a showcase where leading figures examine the general condition of sports in general.

In some instances, the conference has started addressing social issues tangential to sports, but of interest to sports figures. This year SSAC also had a panel featuring rapper Meek Mill and Philadelphia 76ers co-owner Michael Rubin, who are among the principals in the REFORM Alliance, a group trying to change criminal sentencing laws. As Meek Mill said, the group aims to give more people “a shot at life” through sentencing reform.

3,500 attendees, 33 countries, 33 panels …

To be sure, the bulk of SSAC features traditional discussions of sports analytics, which remain highly popular. This year’s 13th edition of the conference featured over 3,500 attendees from 33 countries, 44 U.S. states, 130 professional teams, and over 200 universities. There were 33 panel discussions, 36 “Competitive Advantage” talks, six workshops, a hackathon, and a research paper competition, all in Boston’s Hynes Convention Center on March 1 and 2.

The sheer scope of the conferences also generated convergent discussions, even if they weren’t entirely planned that way. Take the idea that we produce stars by having them specialize in one sport early on — or that we can identify future NBA stars at age 13. 

“The earlier you push specialization, the more likely it is you put the wrong person into the wrong discipline,” said David Epstein, science writer and author of the new book “Range: Why Generalists Triumph in a Specialized World,” which draws upon research studies to argue that sports specialization is wildly counterproductive.  And that’s even on its own narrow terms; the best athletes can emerge much later than people realize.

Instead, said Epstein — in an onstage conversation with popular writer Malcolm Gladwell — we should be encouraging kids to enjoy a broad-based “physical literacy” that emerges out of playing many sports, along with other pursuits.

“We basically burn out a lot of people with suboptimal development,” said Epstein, adding that in youth sports, “The systems are setting you up to force you to specialize even if it’s not best for you.”

At times, Epstein notes, this reaches absurd levels, such as the sign he saw in Brooklyn for an under-age 6 travel soccer team — which exists because “it’s so hard to find good competition for 5-year-olds in a city of 9 million people,” he added facetiously.

“I have a rule about travel sports,” Gladwell added, “which is, you should never travel for an amount of time longer than it takes to play the game.”

Moreover, Gladwell added, “We have all been infected by this pernicious notion that the only way to get better at X is to specialize in X.” Admittedly, some people might have come away with that impression after reading Gladwell’s 2008 book, “Outliers,” which suggests that excellence in a discipline may require roughly 10,000 hours of practicing it. 

But on the stage Saturday — and in a conversation meant to update a debate the same two authors had at SSAC five years ago — Gladwell said he had been persuaded by much of the evidence Epstein had marshalled in favor of playing sports broadly to achieve later excellence in one sport.

“A large amount of hours [to achieve excellence] is true, but I thought that meant specialization, which is false,” Gladwell said to Epstein. “Thank you — you’ve made me smarter.”

Requestioning everything

Indeed, this year’s SSAC seemed to attract a significant proportion of freewheeling panelists, as well as athletes ready to question some basic practices in sports. Take ice hockey, where new player-tracking data is being made available for all NHL teams — but has yet to spread across gender lines, suggested Meghan Duggan, a standout forward and three-time Olympic medalist on the U.S. women’s national hockey team.

“Having more access, definitely on the women’s side, [so] you can get to the numbers and the data quickly, would make a huge difference, in terms of prepration for the games,” Duggan said.

One entertaining SSAC panel featured conference co-founder Daryl Morey — general manager of the NBA’s Houston Rockets — questioning soccer tactics, while speaking with soccer analyst Ted Knutson and soccer broadcaster Roger Bennett.

“I get endlessly just frustrated watching soccer,” said Morey. Too many teams, he suggested, prize nonthreatening possession of the ball, rather than counterattacking into space.

A fair amount of data backs that idea up, as the panelists noted. But, as Morey noted, “Until [teams] have very, very senior buy-in [to analytics] with money behind it, it’s sad to say, you almost don’t have anything” going.

However, the data do not really back up another Morey complaint, that teams should avoid passing the ball back to the goalkeeper. In that case, Knutson explained, this move helps teams switch the attacks to the opposite side of the field, and, the numbers show, slightly increases opportunities to score.

SSAC closed with another one-on-one conversation, between author Michael Lewis and Washington State University football coach Mike Leach, whose spread-out, pass-heavy “Air Raid” offenses have been producing winning teams for decades, but whose ideas are only now seeping into the NFL.

Leach said he has long been told his offensive system would not translate to professional football. However, he said, “If you can do it in high school, with rare exception, you can do it anywhere else.” The negativity of traditional-minded sports people toward innovators, he added, is something people in sports analytics should just shrug off.

“It’s all just narrow-minded bunk from people who are all just too selfish or lazy to think about it,” Leach said.

Chernobyl: How bad was it?

Tue, 03/05/2019 - 11:59pm

Not long after midnight on April 26, 1986, the world’s worst nuclear power accident began. Workers were conducting a test at the Chernobyl Nuclear Power Plant in the Ukraine when their operations spun out of control. Unthinkably, the core of the plant’s reactor No. 4 exploded, first blowing off its giant concrete lid, then letting a massive stream of radiation into the air.

Notoriously, the Soviet Union kept news of the disaster quiet for a couple of days. By the time the outside world knew about it, 148 men who had been on the Chernobyl site — firefighters and other workers — were already being treated in the special radiation unit of a Moscow hospital. And that was just one sliver of the population that wound up seeking medical care after Chernobyl. 

By the end of the summer of 1986, Moscow hospitals alone had treated about 15,000 people exposed to Chernobyl radiation. The Soviet republics of Ukraine and Belarus combined to treat about 40,000 patients in hospitals due to radiation exposure in the same period of time; in Belarus, about half were children.

And while 120,000 residents were hastily evacuated from the “Zone of Alienation” around Chernobyl, about 600,000 emergency workers eventually went into the area, trying to seal the reactor and make the area safe again. About 31,000 soldiers camped out near the reactor, where radioactivity reached about 1,000 times the normal levels within a week, and contaminated the drinking water.

Which leads to the question: How bad was Chernobyl? A 2006 United Nations report contends Chernobyl caused 54 deaths. But MIT Professor Kate Brown, for one, is skeptical about that figure. As a historian of science who has written extensively about both the Soviet Union and nuclear technology, she decided to explore the issue at length.

The result is her new book, “Manual for Survival: A Chernobyl Guide to the Future,” published this month by W.W. Norton and Co. In it, Brown brings new research to bear on the issue: She is the first historian to examine certain regional archives where the medical response to Chernobyl was most extensively chronicled, and has found reports and documents casting new light on the story.

Brown does not pinpoint a death-toll number herself. Instead, through her archival research and on-the-ground reporting, she examines the full range of ways radiation has affected residents throughout the region, while explaining how Soviet politics helped limit our knowledge of the incident.

“I wrote this book so it’s something we take a look at more seriously,” says Brown, a professor in MIT’s Program in Science, Technology, and Society.

Lying to themselves

To see how the effects of Chernobyl could be much more widespread than previously acknowledged, consider a pattern Brown observed from her archival work: Scientists and officials at the local and regional levels examined the effects of Chernobyl on people quite extensively, even performing controlled studies and other robust techniques, but other Soviet officials minimized the evidence of major health consequences.

“Part of the problem is the Soviets lied to themselves,” says Brown. “On the ground it [the impact] was very clear, but at higher levels, there were ministers whose job was to report good health.” Soviet officials, Brown adds, would “massage the numbers” as the data ascended in the state bureaucracy.

“Everybody was making the record look better by the time it go to Moscow,” Brown says. “And I can show that.”

Then too, the effects of Chernobyl’s radiation have been diffuse. As Brown discovered, 298 workers at a wool factory in the city of Chernihiv, about 50 miles from Chernobyl, were given “liquidator status” due to their health problems. This is the same designation applied to emergency personnel working at the Chernobyl site itself.

Why were the wool workers so exposed to radiation? As Brown found after investigating the Chernihiv wool factory itself, Soviet authorities had workers kill livestock from the Zone of Alienation — and then send their useable parts for processing. The wool factory workers had become sick because they were dealing with wool from highly contaminated sheep. Such scenarios may have been significantly overlooked in some Chernobyl assessments.

A significant section of “Manual for Survival” — the title comes from some safety instructions written for local residents — also explores the accident’s effects on the region’s agricultural economy. In Belarus, one-third of milk and one-fifth of meat was too contaminated to use in 1987, according to the official in charge of food production in the state, and levels became worse the following year. At the same time, in the Ukraine, between 30 and 90 percent of milk in “clean” areas was judged too contaminated to drink.

As part of her efforts to study Chernobyl’s effects in person, Brown also ventured into the forests and marshes near Chernobyl, accompanying American and Finnish scientists  — who are among the few to have extensively studied the area’s wildlife in the field. They have found, among other things, the decimation of parts of the ecosystem, including dramatically fewer pollinators (such as bees) in higher-radiation places, and thus radically reduced numbers of fruit trees and shrubs. Brown also directly addresses scientific disagreements over such findings, while noting that some of the most negative conclusions about the regional ecosystems have stemmed from extensive on-the-ground investigations of it.

Additionally, disputes over the effects of Chernobyl also rumble on because, as Brown acknowledges, it is “easy to deny” that any one occurence of cancer is due to radiation exposure. As Brown notes in the book, “a correlation does not prove a connection,” despite increased rates of cancer and other illnesses in the region.

Still, in “Manual for Survival,” Brown does suggest that the higher end of existing death estimates seems plausible. The Ukrainian state pays benefits to about 35,000 people whose spouses apparently died from Chernobyl-caused illnesses. Some scientists have told her they think 150,000 deaths is a more likely baseline for the Ukraine alone. (There are no official or unofficial counts for Belarus and western Russia.)

Chernobyl: This past isn’t even past

Due to the long-term nature of some forms of radiation, Chernobyl’s effects continue today — to an extent that is also under-studied. In the book’s epilogue, Brown visits a forest in the Ukraine where people pick blueberries for export, with each batch being tested for radiation. However, Brown observed, bundles of blueberries over the accepted radiation limit are not necessarily discarded. Instead, berries from those lots are mixed in with cleaner blueberries, so each remixed batch as a whole falls under the regulatory limit. People outside the Ukraine, she writes, “may wake to a breakfast of Chernobyl blueberries” without knowing it.  

Brown emphasizes that her goal is not primarily to alarm readers, but to push research forward. She says she would like her audience — general readers, undergraduates, scientists — to think deeply about how apparently settled science may sometimes rely on contingent conclusions developed in particular political circumstances.

“I would like scientists to know a bit more about the history behind the science,” Brown says.

Other scholars say “Manual for Survival” is an important contribution to our understanding of Chernobyl. J.R. McNeill, a historian at Georgetown University, says Brown has shed new light on Chernobyl by illuminating “decades of official efforts to suppress its grim truths.” Alison MacFarlane, director of the Institute for International Science and Technology Policy at George Washington University, and Former director of the Nuclear Regulatory Commission, says the book effectively “uncovers the devastating effects” of Chernobyl.

For her part, Brown says one additional aim in writing the book was to help us remind ourselves that our inventions and devices are fallible. We need to be vigilant to avoid future disasters along the lines of Chernobyl.

“I think it could be a guide to the future if we’re not a little bit more thoughtful, and a little more transparent” than the Soviet officials were, Brown says.

Mark Silis named vice president for information systems and technology

Tue, 03/05/2019 - 2:30pm

Mark Silis has been appointed MIT’s vice president for information systems and technology, effective March 1. A 15-year veteran of IS&T, Silis has served as associate vice president since 2015.

The appointment was announced today in an email to MIT faculty and staff from Executive Vice President and Treasurer Israel Ruiz.

“This wealth of experience has given Mark a deep appreciation and understanding of the MIT culture, and he brings in-depth technical knowledge, operational strength, and exceptional leadership skills to the position of VP,” Ruiz wrote. “He has demonstrated an unwavering dedication to the IS&T organization and enduring commitment to MIT through a period of significant change.”

Silis has been with IS&T since 2003, first as a programmer, then manager of the network and infrastructure services team. He became director of operations and infrastructure services in 2010.

Since 2015, Silis has served as associate vice president, managing 150 full-time employees and overseeing a portfolio of core IT infrastructure services, including the campus network, telecommunications services, data centers, cloud infrastructure, collaboration services, security, and customer support.

Over the past several years, IS&T has embraced a “cloud-first” strategy to rapidly provide MIT with the benefits of the broader IT industry transition to cloud computing models. This recent evolution of the IS&T portfolio has seen the introduction of new services such as Dropbox, Duo, CrashPlan, and Tableau, and the migration of IS&T’s data centers to the cloud. One of IS&T’s major achievements during this period was the migration of many elements of MIT’s infrastructure portfolio to the cloud, including approximately 3,000 servers and the core SAP administrative infrastructure supporting the Institute’s financial, human resources, and facilities business processes.

“We have made an ambitious effort as an organization to embrace the cloud and adopt new ways of doing things, as the opportunities in our industry shift,” Silis says. “MIT has been leading the way in the higher education community in terms of embracing those opportunities, and our staff has done a tremendous job in helping MIT realize the benefits from this unique moment in the evolution of IT.”

As vice president, Silis will lead IS&T in delivering technology systems and services to the MIT community in support of the Institute’s education, research, and administrative programs. He will alo work with the Information Technology Governance Committee on the development of information technology policy at MIT.

“People can often see the rapid pace of technology change as daunting, but MIT embraces it as a force for good, for the advancement of society, and as an opportunity for what we can learn and new problems we can solve,” Silis says. “I consider myself a problem solver by trade, and this new role is an incredible opportunity to be part of that great problem-solving tradition that is MIT, and support MIT as technology becomes an increasingly embedded element in all our activities.”

Silis succeeds John Charles, who headed IS&T from 2013 until he retired in 2018.

Ruiz expressed his gratitude to Associate Provost Krystyn Van Vliet and Deputy Executive Vice President Anthony Sharon for leading the search, and to all of the members of the search committee for their dedication and service.

Making a path to ethical, socially-beneficial artificial intelligence

Tue, 03/05/2019 - 12:25pm

Toward the close of the three-day celebration of the MIT Stephen A. Schwarzman College of Computing, there was one inescapable takeaway: "We are at an inflection point. With the progressing technologies of artificial intelligence, we are on the verge of incredible things," said IBM Executive Vice President John E. Kelly.
 
Less clear to many participants and audience members after a whirlwind of TED-like talks, demonstrations, and discussion was whether advanced computation can truly work primarily for the benefit of humanity.
 
"We are undergoing a massive shift that can make the world a better place," noted David Siegel, co-founder and co-chairman of Two Sigma. "But I fear we could move in a direction that is far from an algorithmic utopia."
 
Meeting the challenges of artificial intelligence

Many speakers at the three-day celebration, which was held on Feb. 26-28, called for an approach to education, research, and tool-making that combines collective knowledge from the technology, humanities, arts, and social science fields, throwing the double-edged promise of the new machine age into stark relief.

As Melissa Nobles, the Kenan Sahin Dean of MIT’s School of Humanities, Arts, and Social Sciences, introduced the final panel of the celebration, she reinforced the need for such an approach, noting that that the humanities, social sciences, and arts are grappling “with the ways in which computation is changing the world,” and that “technologists themselves must much more deeply understand what they are doing, how they are deeply changing human life."

The final panel was “Computing for the People: Ethics and AI,” moderated by New York Times columnist Thomas Friedman. In a conversation afterward, Nobles also emphasized that the goal of the new college is to advance computation and to give all students a greater “awareness of the larger political, social context in which we’re all living.” That is the MIT vision for developing “bilinguals” — engineers, scholars, professionals, civic leaders, and policymakers who have both superb technical expertise and an understanding of complex societal issues gained from study in the humanities, arts, and social science fields.   

The perils of speed and limited perspective
 
The five panelists on “Computing for the People” — representing industry, academia, government, and philanthropy — contributed particulars to the vision of a society infused with those bilinguals, and attested to the perils posed by an overly-swift integration of advanced computing into all domains of modern existence.
 
"I think of AI as jetpacks and blindfolds that will send us careening in whatever direction we're already headed," said Joi Ito, director of the MIT Media Lab. "It's going to make us more powerful but not necessarily more wise.”
 
The key problem, according to Ito, is that machine learning and AI have to date been exclusively the province of engineers, who tend to talk only with each other. This means they can deny accountability when their work proves socially, politically, or economically destructive. "Asked to explain their code, technological people say: ‘We're just technical people, we don't deal with racial or political problems,’" Ito said.

Can AI advance justice, strengthen democracy?

Darren Walker, president of the Ford Foundation, zeroed in on the value void at the center of this new technology.

"If we go deep [into AI tool-making] without a view as to whether AI can advance justice, whether it can strengthen our democracy, if we engage this enterprise without those questions driving our discourse, we are doomed," he said.
 
As a case in point, he cited the predictive analytics of AI that more frequently deny parole to black men than to white men with comparable records. "So AI is in fact reifying and amplifying rather than correcting the historic biases we see every day in America," Walker said. "Will AI be a lever for good, or simply compound disadvantages built into our systems?"
 
Walker also noted that during the recent congressional hearings featuring the testimony of Facebook CEO Mark Zuckerberg, politicians demonstrated ignorance about the workings of social media platforms and of cellphone technology.

"At any other hearing of importance in our society, there would be some smart person sitting behind a congressperson to say, [of the person testifying] ‘Challenge him, he's wrong,’" said Walker. But, he continued, "there are very few people on the Hill working in the public interest on this larger issue of the fourth industrial revolution."
 
Collaborations to make a better world

Panelists also emphasized that the speed of the current technological transformation threatens to undermine efforts to control it. "By the time we realize there's something we must do to right the ship, the ship will be in the middle of the ocean," said Ursula Burns, executive chairman and CEO of VEON, Ltd.
 
But Burns and her fellow panelists believe the new MIT Schwarzman College of Computing, by bringing together computer scientists with scholars from the social sciences and humanities, could help reverse the potentially destructive course of AI.
 
"It's not just about getting a whole bunch of computer scientists writing new programs, it is about making the world a better place," Burns said. "It's active engagement, broad knowledge, and responsibility to other people."

Jennifer Chayes, a technical fellow and managing director of Microsoft Research New England, described an initiative in her labs to promote "fairness, accountability, transparency, and ethics," or FATE, in software platforms and information systems.
 
"It's a nascent field that brings together legal scholars, ethicists, social scientists, and people in AI to ask how we can make some decisions together in a more equitable fashion," she said
 
Chayes also highlighted a method she called “algorithmic greenlining,” which makes it possible to purge inherent bias from decision-making codes that determine who in a particular population gets into a school or receives a loan. "We have a fairness component that takes an objective function and optimizes the data in a way that amplifies equities, rather than inequities," she said.
 
Accountability and human-centered AI

As U.S. Secretary of Defense, Ash Carter, now the director of Harvard University's Belfer Center for Science and International Affairs, said he learned that "accountability as an algorithmic matter isn't automatic," he said. "It needs to be a criterion for people designing AI."
 
Machines easily amplify "crummy data," said Carter, so unless system designers establish "data standards and transparency, you're just massaging yesterday into a perfected version of then rather than creating 'tomorrow,'" he said.
 
Throughout his career, which involved deploying new technologies in the most perilous of circumstances, Carter said he always felt the imperative to act and think with broad ethical considerations in mind. In 2012, he recalled, he issued a directive at the Department of Defense dealing with the use of autonomous weapons.

"It said that with any decisions to use lethal force on behalf of our people, there must be a human involved in the decision — a directive that is still in force to this day," he said.
 
Since machines now weigh in on matters of life and death, justice and freedom, there is an urgency to creating an ethical, socially-informed culture in the fields of AI and data science. Panelists expressed the hope that the new MIT Schwarzman College of Computing would serve as an incubator for more and much stronger interdisciplinary approaches to research and education.
 
The future for bilinguals

"With this new college, we could not just diversify tech, but technify everything else and really work on the hardest problems together in a collaborative way," said Megan Smith ’86, SM ’88, former U.S. chief technology officer and founder and CEO of shift7. "Feeding 22 million children in a free and reduced lunch program is a big data problem, more important than self-driving cars, and it's the kind of computing I think we should do on inequality and poverty."

Panelists also voiced confidence that the new college will serve as a model to other higher education institutions seeking to engage the engineering and liberal arts fields to solve important societal problems collaboratively. They discussed the importance of faculty and students representing not just a range of disciplines, but a range of human beings, people whose lived experiences are relevant to discerning the ethical and societal implications of AI tools.

The panelists also welcomed the opportunity to help nurture the MIT bilinguals — students with expertise in both technical and liberal arts fields — who could swiftly assume positions as policy advisors and leaders in government and industry.
 
"MIT is going to be the anchor of what we will know in this society as public interest technology," predicted Darren Walker. "What MIT is doing will set the pace for every other university that wants to be relevant in the future."

Story prepared by MIT SHASS Communications
Editorial team: Leda Zimmerman and Emily Hiestand

Computing the future

Tue, 03/05/2019 - 11:50am

As part of the public launch of the Stephen A. Schwarzman College of Computing, MIT hosted a special fireside chat Wednesday, Feb.27, at Kresge Auditorium that brought together six MIT professors who have received the Association for Computing Machinery’s esteemed A.M. Turing Award, often described as “the Nobel Prize for computing.”

Moderated by Professor Daniela Rus, director of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL), the conversation included Tim Berners-Lee, the 3Com Founders Professor of Engineering; Shafi Goldwasser, the RSA Professor of Electrical Engineering and Computer Science; Butler Lampson, technical fellow at the Microsoft Corporation and adjunct professor of computer science at MIT; Barbara Liskov, Institute Professor; Ronald Rivest, Institute Professor; and Michael Stonebraker, CTO of Paradigm4 and of Tamr Inc. and adjunct professor of computer science at MIT. (Other MIT Turing Award winners include Professor Silvio Micali, Professor Emeritus Fernando “Corby” Corbato, and the late Professor Marvin Minsky.)

Rus first briefly highlighted the accomplishments of the Turing winners, from Lampson’s contributions to the growth of personal computers to how Berners-Lee and Rivest’s work has fundamentally transformed global commerce.

“Imagine what the world would be like without these achievements in AI, databases, cryptography, and more,” said Rus. “Just try to imagine a day without the World Wide Web and all that it enables — no online news, no electronic transactions, no social media.”

Coming off less as a panel than a casual conversation among friends, the wide-ranging dialogue reflected the CSAIL colleagues’ infectious enthusiasm for each other’s work. One theme was the serendipity of computer science and how often the panelists’ breakthroughs in one area of research ended up having major impacts in other, completely unexpected domains. For example, Goldwasser discussed her work on zero-knowledge proofs and their use in fields such as cloud computing and machine learning that didn’t even exist when she and Micali first dreamed them up. Rivest later joked that the thriving study of quantum computing has been largely driven by the desire to “break” his RSA (named for Rivest-Shamir-Adelman) encryption algorithm.

With a broad lens looking toward the future, panelists also discussed how to create more connections between their work and topics such as climate change and brain research. Liskov cited medical technology, and how more effective data collection could allow doctors to spend less time on their computers and more time with patients. Lampson spoke of the importance of developing more specialized hardware, like Google has with its tensor processing unit.

Another recurring theme during the panel was a hope that the new college can also keep MIT at the center of the conversation about the potential adverse effects of computing technologies.

“The future of the field isn’t just building new functionality for the good, but thinking about how it can be abused,” Rivest said. “It will be crucially important to teach our students how to think more like adversaries.”

The group also reminisced on the letter they penned in the Tech student newspaper in 2017 calling for the creation of a computing school.

“Since we wrote that letter, the MIT administration has created a college and raised $1 billion for a new building and 50 professors,” said Stonebraker. “The fact that they’ve done this all from a standing start in 16 months is truly remarkable.”

The laureates agreed that one of MIT’s core goals should be to teach computational skills in a bidirectional way: that is, for MIT’s existing schools to inform the college’s direction, and for the college to also teach concepts of “computational thinking” that are more generalizable than any one programming language or algorithmic framework.

“I think we do a reasonable job of training computer scientists, but one mission of the college will be to teach the right kinds of computing skills to the rest of campus,” said Stonebraker. “One of the big challenges the new dean is going to face is how to organize all that.”

The panelists also reflected on MIT’s unique positioning to be able to continue to study tough “moonshot” problems in computing that require more than just incremental progress.

“As the world’s leading technological university, MIT has an obligation to lead the forefront of research rather than follow industry,” Goldwasser said. “What separates us from industrial product — and even from other research labs — is our ability to pursue basic research as a pure metric rather than for dollar signs.”

Tissue model reveals how RNA will act on the liver

Tue, 03/05/2019 - 10:59am

Novel therapies based on a process known as RNA interference (RNAi) hold great promise for treating a variety of diseases by blocking specific genes in a patient’s cells. Many of the earliest RNAi treatments have focused on diseases of the liver, because RNA-carrying particles tend to accumulate in that organ.

MIT researchers have now shown that an engineered model of human liver tissue can be used to investigate the effects of RNAi, helping to speed up the development of such treatments. In a paper appearing in the journal Cell Metabolism on March 5, the researchers showed with the model that they could use RNAi to turn off a gene that causes a rare hereditary disorder. And using RNA molecules that target a different gene expressed by human liver cells, they were able to reduce malaria infections in the model’s cells.

“We showed that you could look at how this new class of nucleic acid therapies, especially RNAi, could affect rare genetic diseases and infectious diseases,” says Sangeeta Bhatia, the John and Dorothy Wilson Professor of Health Sciences and Technology and Electrical Engineering and Computer Science, a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science, and the senior author of the study.

The liver tissue model can also be used to manipulate metabolic enzyme levels, which could help researchers to predict how different patients would metabolize drugs, allowing them to identify possible side effects earlier in the drug development process.

MIT research scientist Liliana Mancio-Silva is the lead author of the paper. Other authors include Heather Fleming, director of research for Bhatia’s lab; Alex Miller, an MIT graduate student; and Stuart Milstein, Abigail Liebow, Patrick Haslett, and Laura Sepp-Lorenzino of Alnylam Pharmaceuticals.

Liver model

Human liver tissue is notoriously difficult to grow outside of the human body, making it difficult to study how experimental drugs will affect the liver. Several years ago, Bhatia and her colleagues first demonstrated that they could grow human hepatocytes, the main type of liver cell, on special micropatterned surfaces, surrounded by supportive cells. This precision-engineered architecture creates a microenvironment in which human liver cells function much the same way as they do in humans.

Since then, they have used this model to test small-molecule drugs for malaria and other diseases that affect the liver. In their new paper, they decided to try to demonstrate the model’s usefulness for testing the delivery of nucleic acids such as RNA. Through RNA interference, short strands of RNA can be used to block the expression of specific disease-causing genes.

To explore RNA-based therapies, the researchers decided to model two different types of disease: genetic disorders and infectious diseases. As a model genetic disorder, the researchers chose alpha-1 antitrypsin-associated liver disease. This rare disease causes the alpha-1 antitrypsin protein to misfold and accumulate in hepatocytes, damaging them.

They found that the RNA they delivered to the cells of the liver model could reduce expression of the implicated protein by about 95 percent. Dozens of other disorders of the liver could benefit from genetic manipulation, Bhatia says.

The researchers also tested an RNAi treatment designed to treat infectious diseases by turning down genes expressed by the host, which the pathogen normally exploits to infect the host. In this case, they delivered RNA that interferes with a gene that encodes a cell surface receptor that the malaria parasite requires to get into liver cells and infect them.

Other host genes could be targeted to treat infectious diseases such as hepatitis B. In some patient settings, Bhatia says, this kind of treatment could be preferable to having patients take daily pills over a long period of time, because a single shot of RNA has been shown to turn down gene expression for several weeks.

Drug screening

The researchers also showed that this model could be useful for testing the possible side effects of traditional small-molecule drugs. The liver is responsible for metabolizing such drugs, and liver damage from these drugs is one of the biggest reasons that clinical trials fail.

To make matters more complicated, different people can express varying levels of the metabolic enzymes used to break down drugs, so potential drugs need to be tested under different conditions. This is usually done in human liver tissue treated with drugs that inhibit certain metabolic enzymes. However, these drugs are not highly specific and can block multiple metabolic pathways at once.

In this study, the researchers used RNA interference to reduce levels of two metabolic enzymes that belong to a family known as cytochromes P450. They were then able to test how the liver cells metabolized acetaminophen (Tylenol) and atorvastatin (Lipitor), which can damage the liver in some cases. They showed that the tissue model accurately replicated how these drugs are broken down when varying levels of metabolic enzymes are present.

This kind of drug screening could make it easier for researchers to test the potential responses of many different types of people, using cells from just one donor, manipulated with RNAi, Bhatia says.

In future studies, the researchers plan to study whether this model could be useful for studying gene therapy, which involves delivering DNA encoding a gene that is missing or defective. For example, hemophilia could be treated by delivering the gene for the clotting factor that hemophilia patients lack.

The research was funded by the Bill and Melinda Gates Foundation, Alnylam Pharmaceuticals, and the Koch Institute Support (core) Grant from the National Cancer Institute.

Q&A: Meet the former all-star pitcher turned MIT student

Tue, 03/05/2019 - 9:58am

A former Major League Baseball pitcher has been expanding his repertoire this year at the MIT Sloan School of Management. Chris Capuano — an 18-game winner in 2005, an all-star in 2006, and a 12-year veteran who last pitched in 2016 — is part of the prestigious Sloan Fellows Program, earning his MBA in an accelerated one-year span. For Capuano, it’s a return to university life; he received his BA in economics from Duke University before reaching the majors.

MIT News spoke with Capuano at the 2019 MIT Sloan Sports Analytics Conference, where Capuano appeared on a panel discussing the use of tracking data in sports. During his career, Capuano twice returned from “Tommy John” surgery — replacement of an elbow ligament — and maintains an interest in using biomedical data in sports. He is also an advisor for Boston Biomotion, a startup developing a new resistance training system. This interview has been edited for length.

Q: You’re in the MIT Sloan Fellows MBA Program right now. How’s that going?

A: My experience has been exceeding expectations. There are 110 fellows in my cohort, and 14 Americans. The rest of the fellows come from I think 37 countries. So it’s an extremely diverse group, an experienced group. I think the average age is about 38, 39, and a lot of different industries are represented. So the content was what I expect from MIT. I know that I’m at MIT, given the quantitative nature and challenging nature of my classes. [But] the dynamism and diversity and just the quality of the other people, and the passion for solving some of these other big problems out there in the world, that’s what’s impressed me the most.

Q: You twice returned from major surgery, and pitched in the majors for 12 years without, in your own view, having remarkable ability by big-league standards. How much of your interest in analytics comes from seeking an edge in those circumstances? Or would it have been there anyway?

A: I think perhaps I would be there anyway. I was always very analytical and looking for ways to challenge myself and expand my thinking when I was a player. But certainly we’re all products of our experience. And I think my experience in battling through injuries and having some real ups and downs related to that, that’s probably the biggest factor that caused me to try to stay current with all the methods for optimizing performance and recovery. … Getting to the big leagues is hard. Staying in the big leagues is harder. [You have to] try to keep growing and improving, because you can’t just stay the same. The league catches up to you; players catch up to you. So it takes a lot of work to maximize and optimize. You have to keep up or you fall behind.

Q: Once you’re finished at MIT Sloan, what are the next steps for you?

A: I’m currently — and I plan to stay — an advisor to Boston Biomotion and help them develop and market their Proteus system. I believe in the technology; athletes love using it; I love using it and training on it. That’s something I’ll continue to do. But I also intend to develop a very close association with the Major League Baseball Players Association [MLBPA], which is our union. When I graduate from the [Sloan Fellows] program, I plan on setting up shop in New York and working with them on their business affairs, collective bargaining, all sorts of things related to players, including player educational opportunities — we have a nonprofit called the Players Trust. I’m looking forward to … working in the game on the union side.

Q: How did that come about? Is it because you were a team representative [for the players’ union] during your career?

A: As a young player in the majors, if you have a college degree, a lot of times the older guys will say, “You’re going to go to these meetings. You’re going to learn about the issues in the game and come back and report to us.” So that’s what I did, and I have really enjoyed that as sort of a second education throughout my baseball career.

Q: That’s maybe better than other kinds of hazing rituals for young players.

A: Oh, there were others.

Q: How conscious are you and other baseball players of the union’s past? It’s shaped a lot of baseball history and the structure of modern professional sports.

A: In baseball we do a very good job of connecting the fraternity across generations. Guys are very much aware of the players in the late 1960s and the 1970s like [former player] Curt Flood, of the leadership of [former union leader] Marvin Miller, and the sacrifices the guys made to leave us with this game, this industry that we inherited. Guys definitely have a lot of respect for the generation that came before and have a good grasp of the history of labor relations. … That connection with the past is not only informative and helps you make decisions, but it’s important from a cultural standpoint. Some of the things we think about here at Sloan, when we talk about organizations, are [precisely] about organizational identity and culture, and how you [sustain] that.

Q: Your panel today talked a lot about keeping new forms of medical data private. What are your thoughts about that?

A: These are things the union thinks about a lot. I have an interesting perspective because I’m [familiar with] both sides of the issue. As a former player I worry a lot about safeguarding the data. At the same time I know how valuable the data can be, in terms of predicting and preventing injury … as I talked about in the panel, becoming your own innovation lab, if you will. So I’m coming at it from that standpoint, but I’m also coming at it from the labor standpoint. I want to protect the players, make sure there’s no misuse of the data.

The data has value. There’s no doubt. It has value from a player development perpective, from an evaluation perspective, from a commercial perspective. It’s here, it’s coming, and there’s no stopping it; it’s just too valuable. But the instututions need to be strong, the agreements [over its use] need to be strong, and it’s just something we have to keep working through for quite a long time.

We really need to work together, is what we need to do. MLB and the MLBPA need to work together on these issues, because the potential benefit, if these things are used responsibly, is just fantastic.

Negotiating with infrastructure cyberterrorists

Mon, 03/04/2019 - 11:59pm

In ransomware cyberattacks, hackers steal a victim’s sensitive data and threaten to publish or block access to it unless a ransom is paid. Across the globe each year, millions of ransomware attacks are carried out on businesses, cities, and organizations, costing billions of dollars total in payments and damages. Many technologies can thwart such cyberattacks, but MIT Computer Science and Artificial Laboratory (CSAIL) and Department of Urban Studies and Planning (DUSP) researchers believe there’s more to solving the issue than deploying the latest software.

Based on business negotiation strategies, the researchers designed a “cyber negotiation” framework, published recently in the Journal of Cyber Policy, that details a step-by-step process for what to do before, during, and after an attack. Lead author and CSAIL and DUSP researcher Gregory Falco, who founded the critical-infrastructure cybersecurity startup NeuroMesh, spoke to MIT News about the plan. He was joined on the paper by co-authors Alicia Noriega SM ’18, a DUSP alumna; and Lawrence Susskind, the Ford Professor of Environmental and Urban Planning and a researcher for the Internet Policy Research Initiative and the MIT Science Impact Collaborative.

Q: What are cities, especially, up against with ransomware attacks, and why not just invent better technologies to defend against these attacks?

A: If you think about critical infrastructure, like transportation systems or water service networks, these are often run by city or metro agencies that don’t have tens of millions of dollars to pay experts or companies to deter or combat attacks. Given that cities have amassed all kinds of data on resident activity or infrastructure operations, hackers target these treasure troves of data to sell on the black market. They disrupt critical urban infrastructure on a regular basis in the United States. If someone hacks into a traffic lights and changes the signals that are supposed to be sent to an autonomous vehicle, or if someone hacks smart meters and interferes with our energy system, public health and safety will be at risk.

Cities do have personnel — usually an individual or small team — in charge of protecting critical infrastructure. But, they need a lot more help. Ransomware is one of the rare cases where they can have direct communication with a hacker and can possibly regain control of their data. They need to be ready to do this.

Most of my research has been about using hacker tools against hackers, and one of the most effective hacker tools is social engineering. To that end, we created “Defensive Social Engineering,” a toolbox of social engineering strategies that employ negotiation capacities to alter the way ransomware attacks unfold. Encryption and other high-tech tools won’t help once an attack has begun. We have devised a cyber negotiation framework that can help organizations reduce their cyber risks and bolster their cyber resilience.

Q: What methods did you use to design your cyber negotiation framework? What are some examples of strategies in the plan?

A: Larry [Susskind] is the co-founder of the interuniversity Program on Negotiation at Harvard Law School. We have applied the best negotiation practices to defending critical urban infrastructure from cyberattack. The pathology of most ransomware attacks matches up nicely with what happens in other kinds of negotiations: First, you size up your opponent, then you exchange messages, and ultimately you try to reach some kind of agreement. We focus on all three cyber negotiation stages: before, during, and after an attack.

To prepare before an attack it is necessary to raise awareness across the organization of how to handle an attack if one occurs. Public agencies need attack response plans. During an attack, agencies have to figure out the costs of complying or not complying with the demands of an attacker, and consult their legal team regarding their liabilities. Then, if the circumstances are right, they need to negotiate with the hacker, if possible. After an attack, it is important to review what happened, share information with appropriate authorities, document what was learned, and engage in damage control. Cyber negotiation does not necessarily require paying ransom. Instead, it focuses on being flexible and knowing how to manipulate the situation before, during, and after an attack. This approach to negotiation is a form of risk management.

To validate our framework, we interviewed a sample of infrastructure operators to understand what they’d do in the case of a hypothetical ransomware attack. We found that their existing process could integrate well with our cyber negotiation plan, such as making sure they have good response protocols up and ready, and having communication networks open across their internal organization to ensure people know what’s going on. The reason our negotiation strategy is valuable is because these operators all handle different pieces of the cybersecurity puzzle, but not the full puzzle. It’s essential to look at the whole problem.  

While we found that no one wants to negotiate with an attacker, under certain circumstances negotiation is the right move, especially when agencies have no real-time backup systems in place. A classic case was last year in Atlanta, where hackers cut off digital services, including utility, parking, and court services. The city didn’t pay the ransom of roughly $50,000, and now they have paid more than $15 million in fees trying to figure out what went wrong. That is not a great equation.

Q: In the paper, you retroactively apply your framework to two real ransomware attacks: when hackers locked down England’s National Health Service patient records in 2017, and a 2016 incident where hackers stole data on millions of users of Uber, which paid a ransom. What insights did you glean from these case studies?

A: For those, we asked, “What might have gone better if they prepared for and used our negotiation framework?” We conclude that there were a number of specific actions they could have taken that might well have limited the damage they faced. NHS, for instance, needed greater awareness among its employees about the dangers of cyberattack and more explicit communications about how to forestall such attacks and limit their spread. (For the ransomware to be successfully installed, an employee needed to click on an infected link.) In Uber’s case, the company didn’t engage authorities and never conducted damage control. That in part led to Uber losing its license to operate in London.

Cyberattacks are inevitable, and even if agencies are prepared, they are going to experience losses. So, dealing with attacks and learning from them is smarter than covering up the damage. A main insight from all of our work is not to get bogged down in installing expensive technical solutions when their defensive social engineering actions that can reduce the scope and costs of cyberattacks. It helps to be interdisciplinary and mix and match methods for dealing with cybersecurity problems like ransomware.

2019 MacVicar Faculty Fellows named

Mon, 03/04/2019 - 11:59pm

The Office of the Vice Chancellor and the Registrar’s Office have announce this year’s Margaret MacVicar Faculty Fellows: economics Professor Joshua Angrist, computer science Professor Erik Demaine, anthropology Associate Professor Graham Jones, and comparative media studies Professor T. L. Taylor. They will be honored this Friday, March 8, during MacVicar Day.

The fellows come from across the Institute and represent a diverse range of academic disciplines. This academy of scholars is committed to exceptional instruction and innovation in education, embodying through their work the continuing promise of an MIT education for the future. This year’s MacVicar Day program seeks to examine what this future looks like.

A symposium, entitled “The Educated Student: Thinking and Doing for the 21st Century,” will feature lightning talks by professors and students that address the following questions: “What’s important to today’s learner?” and “How is MIT adapting to these changing needs?”

In addition to celebrating the new fellows, Vice Chancellor Ian Waitz will host the event, which will take place on Friday from 2 to 4 p.m. in Room 6-120. A Q&A panel and reception will follow. All in the MIT community are welcome to attend.

The Margaret MacVicar Faculty Fellows Program was named to honor the life and contributions of the late Margaret MacVicar, professor of physical science and the first dean for undergraduate education. It recognizes exemplary undergraduate teaching by appointing fellows to 10-year terms in which they receive $10,000 per year of discretionary funds. Faculty are nominated through letters from colleagues and students.

Joshua Angrist

Joshua Angrist is the Ford Professor of Economics, a director of MIT’s School Effectiveness and Inequality Initiative, and a research associate at the National Bureau of Economic Research. After completing his undergraduate degree at Oberlin College, Angrist received his MA and PhD from Princeton University. He began teaching at MIT in 1996.

“Joshua Angrist is a path-breaking scholar whose brilliant work has advanced the cause of transparency, robustness, and ultimately credibility in empirical economics and public policy for over three decades,” says Parag Pathak, the Jane Berkowitz Carlton and Dennis William Carlton Professor of Microeconomics.

A disruptor and natural experimenter, Angrist isn’t afraid to rock the boat. “There’s always a good argument for why ‘the current way is the best way,’” says his colleague David Autor, the Ford Professor of Economics. “To Angrist’s credit, he pushed hard, made unpopular arguments, and coaxed and goaded the department to innovate in the undergraduate program. … He has devoted his scholarship, pedagogy, and Institute service to advancing teaching brilliantly, modernizing the economics curriculum broadly, and improving the MIT undergraduate experience at the Institute-wide level.”

Duane Boning, professor of electrical engineering and computer science and chair of the Committee on the Undergraduate Program, concurs, admiring how Angrist encourages the committee to consider “big ideas and not just small tweaks” when it comes to the evolution of the undergraduate curriculum. “Josh is quite willing to be controversial in his positions and arguments — resulting in lively and much richer discussions that might not otherwise be possible," says Boning.

When it comes to advising, Angrist goes the extra mile. Students considering doctoral programs appreciated how he shared his own experiences with graduate school and put them in touch with colleagues and former students who could offer additional perspectives. One wrote, “In econometrics, we argue causality when there is an exogenous shock to the system. Prof. Angrist is my exogenous shock. It was a stroke of random luck that I took his 14.32 class my sophomore spring, but that experience pushed me from a clueless undergraduate… to a Ph.D. candidate in economics hoping to use econometric techniques to better the world.”

“I love teaching, especially at MIT,” Angrist says. “It’s gratifying to know that many of my students have as much fun in my classes as I do.”

Erik Demaine

In 2001, at the age of 20, Professor in Computer Science Erik Demaine became the youngest faculty member ever hired by MIT. He has been at the Institute ever since, pursuing wide-ranging interests that have led to a MacArthur “genius” grant and art displays at the Museum of Modern Art in New York and the Smithsonian Institution. In 2017, he helped construct a universal algorithm for folding origami shapes, a project which he had initially begun almost two decades prior.

“I chose to join MIT’s faculty because of their care for undergraduate education and the constant quest for improvement,” Demaine says. “It’s awesome to share this honor with the many great educators here.”

Charles Leiserson, a Course 6 colleague, described what it was like to co-teach with Demaine during his first term at MIT: “In my 37 years at MIT, this teaching experience was surely among my most pleasurable. Erik … [was] well-prepared, articulate, inspiring, empathetic, imaginative, engaging, and fun. He taught with a passion. I have never seen a brand-new faculty member with such a complete ‘package’ of teaching skills.”

Many nominators spoke of how his meticulous lecture notes have become the gold standard for teaching in the field. Demaine’s notes “convey the magic of algorithms in a clean, crisp, and inviting, yet still complete way,” says Konstantinos Daskalakis, professor of computer science and electrical engineering.

“Erik has a deep conceptual view of how to organize and explain the interplay between the ideas in algorithm design,” adds Ronitt Rubinfeld, another EECS professor. “His notes especially shine in the difficult topics, such as how to teach dynamic programming. His deep and thoughtful classification of the different ideas that go into explaining why dynamic programming algorithms work is well beyond any explanation that I have heard in the past 30 years.”

“Erik has a joyful, energetic style of teaching that everyone loves,” says Srini Devadas, the Webster Professor of Electrical Engineering and Computer Science.

This energy is evident in his classes, which are centered around collective problem-solving. To harness this spirit of cooperation, he developed a tool called Coauthor. As one student explained, “Coauthor allowed people to collaborate even beyond class hours … as people suggested different directions, and made incremental progress over several days.”

“The combination of both the drive and ability to impact student learning for the better is what makes Erik such an effective teacher, both inside and outside the classroom,” said another student.

Graham Jones

An “infectious passion.” An “unassuming nature” and a “willingness to learn and grow.” A “commitment to excellence.” Nominators enthusiastically listed the qualities that made Graham Jones, associate professor of anthropology, worthy of the MacVicar Fellow honor.

Jones came to MIT in 2010, following three years as a lecturer and postdoctoral member of the Princeton Society of Fellows. He received an undergraduate degree in literature at Reed College before attending New York University to complete his PhD in anthropology.

Calling the recognition “both thrilling and humbling,” Jones expressed gratitude for his colleagues and reflected on how deep thought and conversation with students can lead to a strong sense of shared purpose. “Anthropology has been called the most humanistic of the sciences and the most scientific of the humanities. I have learned to embrace that duality,” he says. “This makes for a really exciting way for me to invite brilliant students with backgrounds in science and engineering into the heart of a discipline that seeks to help us understand what it means to be human.”

One particular class, 21A.157 (The Meaning of Life), seems to have had an outsized effect on the students who have taken it. “Given the name, I came in with high expectations,” wrote one student nominator. “Professors Jones and [Heather] Paxson, who co-taught the class, did not disappoint.”

Another wrote: “The emphasis that Professor Jones places on fostering discussion that makes the abstracted ideas in a reading immediate and relevant creates an environment where students come into class bursting at the seams to start picking apart the day’s topics.”

“Graham is without peer in my estimation, always leaving a positive, indelible mark on the students,” says Susan Silbey, the Leon and Anne Goldberg Professor of Humanities, Sociology, and Anthropology, a professor of behavioral and policy sciences at the MIT Sloan School of Management, and the head of the faculty. “Graham’s classes transform the students, setting them on paths of lifelong learning and self-reflection.”

Students emphatically agreed. One wrote, “Professor Jones has been integral to my success as an undergraduate at MIT. I would not have nearly as much confidence, joy, self-respect, or courage as I have now without him.”

T. L. Taylor

“To be given such an honor based on doing work I truly enjoy is a rare gift,” says T. L. Taylor, professor of comparative media studies, upon learning that she had been named a MacVicar Fellow. “Our students are this wonderful mix of super-sharp, hardworking, and humble. I’m constantly impressed with how game they are to think critically and sociologically. Getting to work with them around topics related to media and technology has been incredibly gratifying.”

Taylor received her bachelor’s degree from the University of California at Berkeley and her MA and PhD from Brandeis University. Her classes, such as CMS.614 (Network Cultures) and CMS.616 (Games and Culture), focus on how we interact with online environments.

In addition to promoting inclusion within the e-sports community, she is also active in the Institute’s First Generation Program, which champions students who are the first in their family to attend college. Scott Hughes, professor of physics and fellow program member, explains that Taylor “[is] always bringing a focus on the economic needs that are disproportionately important to first-gen students to our discussions. The passion that T. L. brings to our group’s work exemplifies the commitment to MIT’s undergraduate students that is a hallmark of a MacVicar Fellow.”

Students appreciated Taylor’s ability to help them have a personal conversation with the course material. “Students have the freedom to dive deeper into what really intrigues them without losing sight of the path,” wrote one nominator. “The opportunity for us to personally engage with the content is critical to Taylor’s success in the classroom: It’s how she lets us bridge the gap between the theory and the reality of our personal world,” wrote another.

In her involvement with the Comparative Media Studies/Writing curriculum committee, Taylor is “always sensitive and empathic where students are concerned,” says CMS Professor Heather Hendershot, and this commitment does not end at graduation. One alumnus wrote, “With the benefit of hindsight, I can now say with certainty that it took me two years to realize that T. L. was completely correct about my passions, skills, and what I want to do in the future. I continue to seek her advice even after MIT because she remains just as accessible and compassionate as she was when I was at MIT.”

MIT students take 2nd place in annual Putnam Mathematical Competition

Mon, 03/04/2019 - 11:25am

MIT students captured numerous individual and team honors in the 2018 William Lowell Putnam Mathematical Competition, earning 17 out of the top 27 scores. 

Yuan Yao and Shengtong Zhang were named Putnam Fellows, a distinction given to the top five individual contestants in the competition, and Danielle Wang received the Elizabeth Lowell Putnam Prize, given to the top female contestant. It was her second win in the category.

The combined scores of student team members Junyao Peng, Ashwin Sah, and Yunkun Zhou captured second place in the team competition, just behind first place winner Harvard University. MIT students overall took 11 of the first 15 spots in the demanding six-hour mathematics competition. Counting honorable mentions, 45 of the top 101 students were from MIT. 

The exam consists of 12 problems, worth 10 points each, that students work on over two three-hour sessions on Dec. 1, 2018. Contest results were announced Feb. 25. The highest exam score was 114 out of a possible 120 points. However, as an example of just how tough this exam is, the median score was just 2 points.

The honors also come with cash awards. The team earned earned the Department of Mathematics $20,000 for placing second, with each team member also receiving $800. Putnam Fellows receive $2,500, while the Elizabeth Lowell Putnam Prize winner gets $1,000.

“I am super proud of our students' performance on the Putnam Competition,” said MIT’s Putnam coach and math professor Yufei Zhao. “The number of high scorers from MIT shows the unparalleled strength of our undergraduate math community.”

Department of Mathematics Head Michel Goemans added: “Once again, the performance of our MIT undergrads at the Putnam competition has been phenomenal. We are so fortunate at MIT to have such a large group of mathematically brilliant students.”

Many Putnam competitors have experience in Math Olympiad-type competitions, and MIT students can enroll in the fall 18.A34 (Mathematical Problem Solving: Putnam Seminar). The class is taught by Zhao ’10, PhD ’15, a three-time Putnam Fellow who took the same class under professors Richard Stanley and Hartley Rogers. Zhao shares test-taking strategies, and students practice with past years’ Putnam exams. 

Of the three non-MIT Putnam Fellows, all from Harvard this year, two also have strong MIT ties as 2014 alums of the Department of Mathematics’ PRIMES program: Shyam Narayanan (PRIMES-USA 2014) and David Stoner (RSI 2014). Stoner also studies combinatorics under Zhao.

The 79th Putnam Competition was administered by the Mathematical Association of America. It saw a total of 164 MIT students competing among 4,623 test-takers from 568 U.S. and Canadian institutions. Last year, MIT’s team finished first, and took five of the six Putnam Fellows spots. Overall last year, MIT students took 17 of the top 25 spots, and 38 percent of the top 100 ranking individual students were from the Institute.

Innovating at the speed of light

Mon, 03/04/2019 - 11:00am

The expanding role of computer science education — in every discipline from engineering to the arts — took center stage on Wednesday, Feb. 27, as MIT continued its three-day celebration of the new MIT Stephen A. Schwarzman College of Computing.

More than 300 people filled the Samberg Conference Center for Teach: The Academic Symposium, which featured two keynote addresses and five panel discussions on topics ranging from “Teaching Ethics and Policy in Computer Science” to “Teaching Computer Science to All.”

The day began with welcoming remarks from Provost Martin A. Schmidt, the Ray and Maria Stata Professor of Electrical Engineering and Computer Science (EECS), who described the Schwarzman College as a “transformative opportunity” for MIT.

“In creating something new, we have a clean sheet of paper,” said Schmidt, who later expanded on his comments in a discussion with reporters. “I am confident that what we learn today will indeed shape the creation of the college.”

Schmidt then introduced Farnam Jahanian, president of Carnegie Mellon University, who offered the day’s opening keynote address, “The Future of Higher Education in the Age of Disruption.” He was the first of nearly 30 speakers, who hailed from across MIT as well as from a wide range of other universities, including Columbia University, Cornell University, Georgia Tech, Harvard University, and Stanford University.

Jahanian described the societal changes being wrought by computing advances as unprecedented and pointed out that major technological changes have historically led to innovations in higher education. “The pace of innovation is accelerating dramatically,” he said. “Society, including our education system, must adapt to this new paradigm.”

The increasing demands for an educated workforce and the changing nature of work call for new thinking about how students acquire computing skills, he said. “We’re seeing a shift from an industrial, transactional model of education based on a rigid model to a much more personalized, outcome-based model,” Jahanian said. “Computer scientists have to take a much more expansive but inclusive view of computing.”

The discussions that followed provided a glimpse of such a view, including the panel on teaching computing in arts and humanities, which was moderated by Agustín Rayo, associate dean of the School of Humanities, Arts, and Social Sciences. Featuring MIT faculty from EECS, the Music and Theater Arts Section, and the Department of Economics as well as a computer scientist from Cornell, the panel underscored the synergies between computer science and other fields.

For example, Eran Egozy, a professor of the practice in music technology, gave a lively demonstration of how students in his class can create music with code. And EECS Professor Erik Demaine described using computation to create origami and blown glass.

“The future of the humanities depends on our ability to bring in computational resources, and the ability of computer science to effect societal change depends on bringing humanities to the table,” said Michael Scott Cuthbert, associate professor of music and the director of Digital Humanities at MIT. “I think both futures at MIT are very bright.”

The value of interdisciplinary connections — a central theme of the day — was picked up by the next panel. Moderated by David Autor, Ford Professor Economics, the panel focused on ways to incorporate the teaching of ethics and policy in computer science.

“We should have ethics throughout the computer science curriculum so that [students] think about ethical implication of their designs at the same time they think about writing elegant code and efficient code,” said Barbara Grosz, the Higgins Professor of Natural Sciences at Harvard University. “Ethics is everybody’s responsibility.”

David Danks, head of Carnegie Mellon’s philosophy department, pointed out that while computer science students don’t need to become philosophers — or vice versa — they do need to learn to collaborate and to value other ways of thinking. “Different disciplines just ask different question about the world,” he said.

Echoing MIT President L. Rafael Reif’s call for the Institute to educate students who are “bilingual” in computing and other fields, Hal Abelson, the Class of 1922 Professor of EECS, noted that working across disciplines — notably with policymakers — can give technologists more impact.

“MIT can be a world leader in information policy,” he said, citing the ethical concerns that have emerged from cybersecurity as an important area for input. “We have the opportunity to bring our technological insight into that policy debate.”

The next panel, moderated by MIT Chancellor Cynthia Barnhart, also highlighted the value of interdisciplinary work in the teaching of computing in science and engineering. “What computing does when you wrap it in with [science and engineering] courses is make them actionable,” said Stephen Boyd, chair of the Department of Electrical Engineering at Stanford University, explaining that software applications have made engineering instruction much less theoretical.

“I think infusing computation skills into everything will make students that much more marketable,” said Wendi Heinzelman, dean of the Hajim School of Engineering and Applied Sciences at the University of Rochester.

Following a break for lunch, Asu Ozdaglar, School of Engineering Distinguished Professor of Engineering, head of EECS, and co-chair of the Teach symposium, introduced the second keynote speaker of the day, Harvey Mudd College President Maria Klawe. “The title of her talk beautifully sums up our overarching theme for the day: ‘Computing Is for Everyone,’” Ozdaglar said.

Klawe detailed ways to attract more women and underrepresented minorities to computer science — something Harvey Mudd has had great success in doing. She recommended separating novices from experienced students, providing extensive support, and promoting joint majors with disciplines that typically attract more women and minority students.

“Women and people of color are more likely to be attracted to computer science and engineering if they can see they can work on problems that matter,” she said.

The final two panels of the day picked up Klawe’s themes, as speakers shared their insights first on “Experiences with CS+X Majors and Curricula,” moderated by Eran Ben-Joseph, head of the Department of Urban Studies and Planning, and “Teaching Computing to All,” moderated by Dimitris Bertsimas, the Boeing Leaders for Global Operations Professor of Management at the MIT Sloan School of Management.

Speakers in the former panel (in which the “X” represents any other discipline combined with computer science) detailed the challenges of creating new academic pathways, from the risk of overloading students to the benefits of infusing computational thinking into a broad range of disciplines.

Georgia Tech, for example, began by requiring every student to take the same introductory computer science course. “It was a disaster,” said Charles Isbell, executive associate dean of Georgia Tech’s School of Interactive Computing, explaining that the blanket requirement didn’t take different contexts into account. Since then, Georgia Tech has dropped the idea of a core requirement and instead offers joint degrees, with introductory computer science courses available in different focal areas. “This works great,” he said.

Northeastern University, in comparison, offers combined degrees. Students work with two academic departments but take at least one course that integrates the two disciplines and earn a single degree. “More than half of majors in our college are combined majors,” said Carla E. Brodley, dean of Northeastern’s Khoury College of Computer Sciences, noting that the university also offers “meaningful” minors. 

“The mission of our college is computer science for everyone,” she said.

The last panel picked up on this idea by expanding on the broader mission of computer science education, describing ways to improve K-12 education, online offerings, and lifelong learning to give more people computational skills. 

“We want students to learn how to think computationally, design systems that leverage modularity and abstraction, [and] use them to complement theoretical explorations and physical experiments with computational analysis,” said W. Eric L. Grimson, MIT Chancellor for Academic Advancement and Bernard M. Gordon Professor of Medical Engineering.

To underscore the value of the endeavor, Grimson shared feedback he’d received from one of the more than a million people who have taken his massive open online course on computer science. The student described using his introductory class to retool and enter a new career, calling the experience “a real life-changer.”

In closing, Professor Saman Amarasinghe, associate head of EECS and co-chair of the Teach symposium, thanked the events’ organizers — including a third co-chair, Sanjay Sarma, MIT’s vice president of Open Learning and Fred Fort Flowers and Daniel Fort Flowers Professor of Mechanical Engineering — and said he expected to see many of the day’s ideas implemented at MIT in the years ahead. “I was so amazingly energized after all these talks today,” Amarasinghe said. For a full list of the day’s speakers and topics, please visit the event website.

Among those attending Wednesday’s symposium was Dan Huttenlocher SM ’84, PhD ’88, who was named inaugural dean of the MIT Schwarzman College of  Computing last week. Huttenlocher, currently founding dean of Cornell Tech, a graduate school in New York City that focuses on digital technology and its economic and societal impacts, will assume his new role over the summer.

Related events last week included a free film series, an exposition highlighting student efforts to tackle a wide range of computing challenges, a high-energy panel discussion featuring leading female researchers, and a conversation with several MIT winners of the Association for Computing Machinery A. M. Turing Award, considered the field’s most prestigious honor. The celebration continued Thursday with a daylong event focused on the new college’s direction. Thursday's speakers included Stephen A. Schwarzman, chairman, CEO, and co-founder of Blackstone, who provided the $350 million foundational gift for the Schwarzman College of Computing; former U.S. Secretary of State Henry Kissinger, and Massachusetts Gov. Charlie Baker, among others. Video recordings of many of the events will be available soon on the celebration website.

Solve launches 2019 global challenges

Mon, 03/04/2019 - 10:35am

At the Feb. 28 Hello World, Hello MIT event celebrating the MIT Stephen A. Schwarzman College of Computing, MIT Solve Executive Director Alex Amouyel announced the launch of Solve’s newest set of global challenges: Circular Economy, Community-Driven Innovation, Early Childhood Development, and Healthy Cities.

Solve now seeks tech-based solutions from innovators around the world that address these four challenges, and anyone can submit a relevant solution by the July 1 deadline.

“Through open innovation, we find the most promising tech-based social innovators from all around the world, including those already right here at MIT,” said Amouyel. “These Solver teams use AI, machine learning, and many other technologies to positively improve the lives of thousands already, and hopefully millions more in the future.”

Finalists will be invited to pitch their solutions to Solve’s Challenge Leadership Group — a judging panel of cross-sector leaders and MIT faculty — at Solve Challenge Finals on Sept. 22 in New York City during U.N. General Assembly Week.

The most promising solutions will be selected to form the 2019 Solver Class, and Solve will then deploy its global community of private, public, and nonprofit leaders to build the partnerships needed to scale their work.

To date, Solve’s community has committed more than $7 million in funding to Solver teams, in addition to in-kind support such as mentorship, technical expertise, media and conference exposure, and business and entrepreneurship training.

Over the past six months, Solve staff consulted more than 500 leaders and experts to determine the 2019 global challenges. Solve hosted 14 Challenge Design Workshops in eight countries — in cities ranging from New York to Hong Kong to Abu Dhabi, United Arab Emirates, to Monterrey, Mexico — to collect feedback from communities around the world. More than 30,000 votes were cast online through Solve’s open innovation platform to influence challenge themes.

  1. Circular Economy: How can people create and consume goods that are renewable, repairable, reusable, and recyclable?

  2. Community-Driven Innovation: How can citizens and communities create and improve social inclusion and shared prosperity?

  3. Early Childhood Development: How can all children under age 5 develop the critical learning and cognitive skills they need to reach their full potential?

  4. Healthy Cities: How can urban residents design and live in environments that promote physical and mental health?

As a marketplace for social impact, Solve finds tech entrepreneurs from around the world and brokers partnerships across its community to scale their innovative work — driving lasting, transformational change. Organizations interested in joining the Solve community can learn more and apply for membership here.

Technique streamlines fabrication of 2-D circuits

Mon, 03/04/2019 - 9:13am

Exotic 2-D materials hold great promise for creating atom-thin circuits that could power flexible electronics, optoelectronics, and other next-generation devices. But fabricating complex 2-D circuits requires multiple time-consuming, expensive steps.

In a paper published in PNAS, researchers from MIT and elsewhere describe a technique that streamlines the fabrication process, by growing a 2-D material directly onto a patterned substrate and recycling the circuit patterns.

The researchers carefully grow a single layer of molybdenum disulfide (MoS2), which is just three atoms thick, onto a growth substrate in a chosen pattern. This approach differs from traditional techniques that grow and etch away a material iteratively, over multiple layers. Those processes take a while and increase the chances of causing surface defects that may hinder the performance of the material.

With the new method, using only water, the researchers can transfer the material from its growth substrate to its destination substrate so cleanly that the original patterned substrate can be reused as a “master-replica” type of mold — meaning a reusable template for manufacturing. In traditional fabrication, growth substrates get tossed after each material transfer, and the circuit must be patterned again on a new substrate to regrow more material.  

“When we scale up and make more complex electronic devices, people need to integrate numerous 2-D materials into more layers and specific shapes. If we follow traditional methods, step by step, it will be very time consuming and inefficient,” says the first author Yunfan Guo, a postdoc in the Department of Electrical Engineering and Computer Science (EECS) and the Research Laboratory of Electronics. “Our method shows the potential to make the whole fabrication process simpler, lower cost, and more efficient.”

In their work, the researchers fabricated arbitrary patterns and a working transistor made from MoS2, which is one of the thinnest known semiconductors. In their study, the researchers recycled the same patterned substrate four times without seeing signs of wear.

Guo is joined on the paper by EECS professors Tomas Palacios and Jing Kong; Ju Li, an MIT professor of nuclear science and engineering and of materials science and engineering; Xi Ling of Boston University; Letian Dou and Enzheng Shi of Purdue University; seven other MIT graduate students, postdocs, and alumni; and two other co-authors from Cornell University and Purdue University.

Controlled growth

To design a pattern on a growth substrate, the researchers leveraged a technique that uses oxygen-based plasma to carve patterns into a substrate’s surface. Some version of this technique has been used experimentally before to grow 2-D material patterns. But the spatial resolution — meaning the size of precise structures that can be fabricated — is relatively poor (100 microns), and the electrical performance has been much lower than materials grown using other methods.

To fix this, the researchers conducted in-depth studies into how MoS2 atoms arrange themselves on a substrate surface and how certain chemical precursors can help control the material’s growth. In doing so, they were able to leverage the technique to grow a single layer of high-quality MoS2 within precise patterns.

The researchers used traditional photolithography masks on a silicon oxide substrate, where the desired pattern lies within regions unexposed to light. Those regions are subsequently exposed to the oxygen-based plasma. The plasma etches away about 1-2 nanometers of the substrate in the pattern.

This process also creates a higher surface energy and an enhanced affinity for water-loving (“hydrophilic”) molecules in these plasma-treated regions. The researchers then use an organic salt, called PTAS, that acts as a growth promoter for MoS2. The salt is attracted to the newly created hydrophilic etched regions. In addition, the researchers used sulfur, an essential precursor for MoS2 growth, at a precise amount and temperature to regulate exactly how many of the material’s atoms will form on the substrate.

When the researchers subsequently measured the MoS2 growth, they found it filled in about 0.7 nanometers of the etched pattern. That’s equivalent to exactly one layer of MoS2.

Recycled patterns

Next, the researchers developed a method to recycle the patterned substrate. Traditionally, transferring 2-D materials from a growth substrate onto a destination substrate, such as a flexible surface, requires encasing the whole grown material in a polymer, chemically etching it, and separating it from its growth substrate. But this inevitably brings in contaminants to the material. When the material released, it also leaves behind residue, so the original substrates may not be reused.

Due to the weak interaction between MoS2 and the growth substrate, however, the researchers found they could detach the MoS2 cleanly from the original substrate by submerging it in water. This process, called “delamination,” eliminates the need for using any supporting layer and produces a clean break with the material from the substrate.

“That’s why we can recycle it,” Guo says. “After it’s transferred, because it is purely clean, our patterned substrate is recovered and we can use it for multiple growths.”

The researchers’ innovations introduce far fewer surface defects that limit performance, as measured in electron mobility — how fast electrons move through a semiconductor.

In their paper, the researchers fabricated a 2-D transistor, called a field-effect transistor. Results indicate the electron mobility and “on-off ratio” — how efficiently a transistor flicks between the 1 and 0 computational states — are comparable with the reported values of traditionally grown high-quality, high-performance materials.

The field-effect transistor currently has a spatial resolution of about 2 microns, which is limited only by the laser the microfabrication instruments the researchers used. Next, the researchers hope to shrink the pattern size, and directly integrate complex circuits on 2-D materials using their fabrication technique.

Mini cheetah is the first four-legged robot to do a backflip

Mon, 03/04/2019 - 12:00am

MIT’s new mini cheetah robot is springy and light on its feet, with a range of motion that rivals a champion gymnast. The four-legged powerpack can bend and swing its legs wide, enabling it to walk either right-side up or upside down. The robot can also trot over uneven terrain about twice as fast as an average person’s walking speed.

Weighing in at just 20 pounds — lighter than some Thanksgiving turkeys — the limber quadruped is no pushover: When kicked to the ground, the robot can quickly right itself with a swift, kung-fu-like swing of its elbows.

Perhaps most impressive is its ability to perform a 360-degree backflip from a standing position. Researchers claim the mini cheetah is designed to be “virtually indestructible,” recovering with little damage, even if a backflip ends in a spill.

In the event that a limb or motor does break, the mini cheetah is designed with modularity in mind: Each of the robot’s legs is powered by three identical, low-cost electric motors that the researchers engineered using off-the-shelf parts. Each motor can easily be swapped out for a new one.

“You could put these parts together, almost like Legos,” says lead developer Benjamin Katz, a technical associate in MIT’s Department of Mechanical Engineering.

The researchers will present the mini cheetah’s design at the International Conference on Robotics and Automation, in May. They are currently building more of the four-legged machines, aiming for a set of 10, each of which they hope to loan out to other labs.

“A big part of why we built this robot is that it makes it so easy to experiment and just try crazy things, because the robot is super robust and doesn’t break easily, and if it does break, it’s easy and not very expensive to fix,” says Katz, who worked on the robot in the lab of Sangbae Kim, associate professor of mechanical engineering.

Kim says loaning mini cheetahs out to other research groups gives engineers an opportunity to test out novel algorithms and maneuvers on a highly dynamic robot, that they might not otherwise have access to.

“Eventually, I’m hoping we could have a robotic dog race through an obstacle course, where each team controls a mini cheetah with different algorithms, and we can see which strategy is more effective,” Kim says. “That’s how you accelerate research.”

“Dynamic stuff”

The mini cheetah is more than just a miniature version of its predecessor, Cheetah 3, a large, heavy, formidable robot, which often needs to be stabilized with tethers to protect its expensive, custom-designed parts.

“In Cheetah 3, everything is super integrated, so if you want to change something, you have to do a ton of redesign,” Katz says. “Whereas with the mini cheetah, if you wanted to add another arm, you could just add three or four more of these modular motors.”

Katz came up with the electric motor design by reconfiguring the parts to small, commercially available motors normally used in drones and remote-controlled airplanes.

Each of the robot’s 12 motors is about the size of a Mason jar lid, and consists of: a stator, or set of coils, that generates a rotating magnetic field; a small controller that conveys the amount of current the stator should produce; a rotor, lined with magnets, that rotates with the stator’s field, producing torque to lift or rotate a limb; a gearbox that provides a 6:1 gear reduction, enabling the rotor to provide six times the torque that it normally would; and a position sensor that measures the angle and orientation of the motor and associated limb.

Each leg is powered by three motors, to give it three degrees of freedom and a huge range of motion. The lightweight, high-torque, low-inertia design enables the robot to execute fast, dynamic maneuvers and make high-force impacts on the ground without breaking gearboxes or limbs.

“The rate at which it can change forces on the ground is really fast,” Katz says. “When it’s running, its feet are only on the ground for something like 150 milliseconds at a time, during which a computer tells it to increase the force on the foot, then change it to balance, and then decrease that force really fast to lift up. So it can do really dynamic stuff, like jump in the air with every step, or run with two feet on the ground at a time. Most robots aren’t capable of doing this, so move much slower.”

Flipping out

The engineers ran the mini cheetah through a number of maneuvers, first testing its running ability through the hallways of MIT’s Pappalardo Lab and along the slightly uneven ground of Killian Court.

In both environments, the quadruped bound along at about 5 miles per hour. The robot’s joints are capable of spinning three times faster, with twice the amount of torque, and Katz estimates the robot could run about twice as fast with a little tuning.

The team wrote another computer code to direct the robot to stretch and twist in various, yoga-like configurations, showcasting its range of motion and ability to rotate its limbs and joints while maintaining balance. They also programmed the robot to recover from an unexpected force, such as a kick to the side. When the researchers kicked the robot to the ground, it automatically shut down.

“It assumes something terrible has gone wrong, so it just turns off, and all the legs fly wherever they go,” Katz says.

When it receives a signal to restart, the robot first determines its orientation, then performs a preprogrammed crouch or elbow-swing maneuver to right itself on all fours.

Katz and co-author Jared Di Carlo, an undergraduate in the Department of Electrical Engineering and Computer Science (EECS), wondered whether the robot could take on even higher-impact maneuvers. Inspired by a class they took last year, taught by EECS Professor Russ Tedrake, they set about programming the mini cheetah to perform a backflip.

“We thought it would be a good test of robot performance, because it takes a lot of power, torque, and there are huge impacts at the end of a flip,” Katz says.

The team wrote a “giant, nonlinear, offline trajectory optimizations” that incorporated the robot’s dynamics and actuator capabilities, and specified a trajectory in which the robot would start out in a certain, right-side-up orientation, and end up flipped 360 degrees. The program they developed then solved all the torques that needed to be applied to each joint, from each individual motor, and at every time period between start and end, in order to carry out the backflip.

“The first time we tried it, it miraculously worked,” Katz says.

“This is super exciting,” Kim adds. “Imagine Cheetah 3 doing a backflip — it would crash and probably destroy the treadmill. We could do this with the mini cheetah on a desktop.”

The team is building about 10 more mini cheetahs, each of which they plan to loan out to collaborating groups, and Kim intends to form a mini cheetah research consortium of engineers, who can invent, swap, and even compete with new ideas.

Meanwhile, the MIT team is developing another, even higher-impact maneuver.

“We’re working now on a landing controller, the idea being that I want to be able to pick up the robot and toss it, and just have it land on its feet,” Katz says. “Say you wanted to throw the robot into the window of a building and have it go explore inside the building. You could do that.”

Addressing the promises and challenges of AI

Fri, 03/01/2019 - 5:22pm

A three-day celebration event this week for the MIT Stephen A. Schwarzman College of Computing put focus on the Institute’s new role in helping society navigate a promising yet challenging future for artificial intelligence (AI), as it seeps into nearly all aspects of society.

On Thursday, the final day of the event, a series of talks and panel discussions by researchers and industry experts conveyed enthusiasm for AI-enabled advances in many global sectors, but emphasized concerns — on topics such as data privacy, job automation, and personal and social issues — that accompany the computing revolution.

Kicking off the day’s events, MIT President Rafael Reif said the MIT Schwarzman College of Computing will train students in an interdisciplinary approach to AI. It will also train them to take a step back and weigh potential downsides of AI, which is poised to disrupt “every sector of our society.”

“Everyone knows pushing the limits of new technologies can be so thrilling that it’s hard to think about consequences and how [AI] too might be misused,” Reif said. “It is time to educate a new generation of technologists in the public interest, and I’m optimistic that the MIT Schwarzman College [of Computing] is the right place for that job.”

In opening remarks, Massachusetts Governor Charlie Baker gave MIT “enormous credit” for focusing its research and education on the positive and negative impact of AI. “Having a place like MIT … think about the whole picture in respect to what this is going to mean for individuals, businesses, governments, and society is a gift,” he said.

Personal and industrial AI

In a panel discussion titled, “Computing the Future: Setting New Directions,” MIT alumnus Drew Houston ’05, co-founder of Dropbox, described an idyllic future where by 2030 AI could take over many tedious professional tasks, freeing humans to be more creative and productive.

Workers today, Houston said, spend more than 60 percent of their working lives organizing emails, coordinating schedules, and planning various aspects of their job. As computers start refining skills — such as analyzing and answering queries in natural language, and understanding very complex systems — each of us may soon have AI-based assistants that can handle many of those mundane tasks, he said.

“We’re on the eve of a new generation of our partnership with machines … where machines will take a lot of the busy work so people can … spend our working days on the subset of our work that’s really fulfilling and meaningful,” Houston said. “My hope is that, in 2030, we’ll look back on now as the beginning of a revolution that freed our minds the way the industrial revolution freed our hands. My last hope is that … the new [MIT Schwarzman College of Computing] is the place where that revolution is born.”   

Speaking with reporters before the panel discussion “Computing for the Marketplace: Entrepreneurship and AI,” Eric Schmidt, former executive chairman of Alphabet and a visiting innovation fellow at MIT, also spoke of a coming age of AI assistants. Smart teddy bears could help children learn language, virtual assistants could plan people’s days, and personal robots could ensure the elderly take medication on schedule. “This model of an assistant … is at the basis of the vision of how people will see a difference in our lives every day,” Schmidt said.

He noted many emerging AI-based research and business opportunities, including analyzing patient data to predict risk of diseases, discovering new compounds for drug discovery, and predicting regions where wind farms produce the most power, which is critical for obtaining clean-energy funding. “MIT is at the forefront of every single example that I just gave,” Schmidt said.

When asked by panel moderator Katie Rae, executive director of The Engine, what she thinks is the most significant aspect of AI in industry, iRobot co-founder Helen Greiner cited supply chain automation. Robots could, for instance, package goods more quickly and efficiently, and driverless delivery trucks could soon deliver those packages, she said: “Logistics in general will be changed” in the coming years.

Finding an algorithmic utopia

For Institute Professor Robert Langer, another panelist in “Computing for the Marketplace,” AI holds great promise for early disease diagnoses. With enough medical data, for instance, AI models can identify biological “fingerprints” of certain diseases in patients. “Then, you can use AI to analyze those fingerprints and decide what … gives someone a risk of cancer,” he said. “You can do drug testing that way too. You can see [a patient has] a fingerprint that … shows you that a drug will treat the cancer for that person.”

But in the “Computing the Future” section, David Siegel, co-chair of Two Sigma Investments and founding advisor for the MIT Quest for Intelligence, addressed issues with data, which is at the heart of AI. With the aid of AI, Siegel has seen computers go from helpful assistants to “routinely making decisions for people” in business, health care, and other areas. While AI models can benefit the world, “there is a fear that we may move in a direction that’s far from an algorithmic utopia.”

Siegel drew parallels between AI and the popular satirical film “Dr. Strangelove,” in which an “algorithmic doomsday machine” threatens to destroy the world. AI algorithms must be made unbiased, safe, and secure, he said. That involves dedicated research in several important areas, at the MIT Schwarzman College of Computing and around the globe, “to avoid a Strangelove-like future.”

One important area is data bias and security. Data bias, for instance, leads to inaccurate and untrustworthy algorithms. And if researchers can guarantee the privacy of medical data, he added, patients may be more willing to contribute their records to medical research.

Siegel noted a real-world example where, due to privacy concerns, the Centers for Medicare and Medicaid Services years ago withheld patient records from a large research dataset being used to study substance misuse, which is responsible for tens of thousands of U.S. deaths annually. “That omission was a big loss for researchers and, by extension, patients,” he said. “We are missing the opportunity to solve pressing problems because of the lack of accessible data. … Without solutions, the algorithms that drive our world are at high risk of becoming data-compromised.”

Seeking humanity in AI

In a panel discussion earlier in the day, “Computing: Reflections and the Path Forward,” Sherry Turkle, the Abby Rockefeller Mauzé Professor of the Social Studies of Science and Technology, called on people to avoid “friction free” technologies — which help people avoid stress of face-to-face interactions.

AI is now “deeply woven into this [friction-free] story,” she said, noting that there are apps that help users plan walking routes, for example, to avoid people they dislike. “But who said a life without conflict … makes for the good life?” she said.

She concluded with a “call to arms” for the new college to help people understand the consequences of the digital world where confrontation is avoided, social media are scrutinized, and personal data are sold and shared with companies and governments: “It’s time to reclaim our attention, our solitude, our privacy, and our democracy.”

Speaking in the same section, Patrick H. Winston, the Ford Professor of Engineering at MIT, concluded on an equally humanistic — and optimistic — message. After walking the audience through the history of AI at MIT, including his run as director of the Artificial Intelligence Laboratory from 1972 to 1997, he told the audience he was going to discuss the greatest computing innovation of all time.

“It’s us,” he said, “because nothing can think like we can. We don’t know how to make computers do it yet, but it’s something we should aspire to. … In the end, there’s no reason why computers can’t think like we [do] and can’t be ethical and moral like we aspire to be.”

For founders of new college of computing, the human element is paramount

Fri, 03/01/2019 - 3:30pm

The new MIT Stephen A. Schwarzman College of Computing is destined to become a major center of artificial intelligence research. But a public conversation between the college’s founders on Thursday helped illuminate the very human impulses guiding it.

“It’s a remarkable expression of the human spirit that you have here,” said Stephen A. Schwarzman during a dialogue with MIT President L. Rafael Reif at MIT’s Kresge Auditorium.

Schwarzman is the principal benefactor of the college, which is intended to drive forward research in computing and artificial intelligence, and link computing to every other discipline at the Institute. Its formation represents the biggest change to MIT’s institutional structure since the 1950s. Schwarzman has delivered a $350 million gift to the Institute, as part of the roughly $1 billion college.

To help launch the MIT Schwarzman College of Computing, MIT held a three-day celebration this week, with dozens of speakers appearing from Tuesday to Thursday, among other campus events.

“Anybody from MIT who takes what you do for granted, it’s just that you’ve been here too long,” Schwarzman added. “Every speaker is like magic.”

To an extent, Schwarzman said, the impulse behind the founding of the college came from trips he had taken to China, where he observed intensified Chinese investment in artificial intelligence, and wanted to make sure the U.S. was also on the leading edge of A.I.

“What I was interested in was taking U.S. competitiveness and really punching it up,” said Schwartzman.

And as Schwarzman and Reif recounted, the college’s origins stemmed in part from something eternally human as well: an ongoing series of conversations between them about how to increase the tempo of computing advances. After their initial discussion, Schwarzman said, he encouraged MIT to think bigger about the possible scope of the project.

As Reif noted, he knew that faculty and staff were increasingly emphasizing a need for researchers to be “bilingual,” in terms of knowing their own disciplines, and understanding how computing could help that disciplinary research.

Moreover, Reif added, while China is very strong in certain applied areas of artificial intelligence, he understood that the U.S. has unrivaled strengths in education and research, making the idea of a new computing college at MIT all the more likely to succeed.

Referring to the U.S., Reif said, “We are extremely strong in human capital in this space. Let’s just invest in ourselves and see what happens.”

Thursday afternoon’s events also included an onstage conversation about artificial intelligence between former U.S. Secretary of State Henry Kissinger and columnist Thomas L. Friedman of The New York Times.

Kissinger expressed general concern about the potentially unpredictable consequences of artificial intelligence, extending a point he raised in an essay in The Atlantic last summer.

“Working in this field is a tremendous responsibility and a tremendous challenge,” Kissinger said.

For his part, Friedman, mostly serving as an interlocutor, suggested that these advanced technologies mean humans “have never been more Godlike” than they are now. He added that “at a minimum a simple golden rule” — of equitable ethical treatment among people — “is going to be essential” for society.

At the start of the session, Robert Millard, chair of the MIT Corporation, introduced Reif and Schwarzman while noting the significance of the new college’s launch. Millard called Reif “an inspired leader who has in his tenure become the senior spokesman for higher education, in science and technology generally.”

Schwarzman, Millard observed, has “accelerated MIT further into the future” with his support for the college.

One of the celebration’s closing events was a panel called “Computing for the People: AI and Ethics.” In his discussion with Reif, Schwzarman also offered his thoughts on the ethics and social impact of innovation.

The curriculum of the new college will include ethics, and, as Schwarzman noted, it will always be important to “have a focus on the workforce … [and] the people who get dislocated” by technology.  

“The technology is going to affect the whole world, and we have to get it right,” Schwarzman said.

Spider silk could be used as robotic muscle

Fri, 03/01/2019 - 2:00pm

Spider silk, already known as one of the strongest materials for its weight, turns out to have another unusual property that might lead to new kinds of artificial muscles or robotic actuators, researchers have found.

The resilient fibers, the team discovered, respond very strongly to changes in humidity. Above a certain level of relative humidity in the air, they suddenly contract and twist, exerting enough force to potentially be competitive with other materials being explored as actuators — devices that move to perform some activity such as controlling a valve.

The findings are being reported today in the journal Science Advances, in a paper by MIT Professor Markus Buehler, head of the Department of Civil and Environmental Engineering, along with former postdoc Anna Tarakanova and undergraduate student Claire Hsu at MIT; Dabiao Liu, an associate professor at Huazhong University of Science and Technology in Wuhan, China; and six others.

Researchers recently discovered a property of spider silk called supercontraction, in which the slender fibers can suddenly shrink in response to changes in moisture. The new finding is that not only do the threads contract, they also twist at the same time, providing a strong torsional force. “It’s a new phenomenon,” Buehler says.

“We found this by accident initially,” Liu says. “My colleagues and I wanted to study the influence of humidity on spider dragline silk.” To do so, they suspended a weight from the silk to make a kind of pendulum, and enclosed it in a chamber where they could control the relative humidity inside. “When we increased the humidity, the pendulum started to rotate. It was out of our expectation. It really shocked me.”

The researchers were able to decode the molecular structure of the two main proteins, shown here, that make up spider dragline silk. One of these, MaSp2, contains proline, which interacts with water molecules to produce the newly discovered twisting motion.

The team tested a number of other materials, including human hair, but found no such twisting motions in the others they tried. But Liu said he started thinking right away that this phenomenon “might be used for artificial muscles.”

“This could be very interesting for the robotics community,” Buehler says, as a novel way of controlling certain kinds of sensors or control devices. “It’s very precise in how you can control these motions by controlling the humidity.”

“This is a fantastic discovery because the torsion measured in spider dragline silk is huge, a full circle every millimeter or so of length,” says Pupa Gilbert, a professor of physics, chemistry, and materials science at the University of Wisconsin at Madison, who was not involved in this work. Gilbert adds, “This is like a rope that twists and untwists itself depending on air humidity. The molecular mechanism leading to this outstanding performance can be harnessed to build humidity-driven soft robots or smart fabrics.”

Spider silk is already known for its exceptional strength-to-weight ratio, its flexibility, and its toughness, or resilience. A number of teams around the world are working to replicate these properties in a synthetic version of the protein-based fiber.

While the purpose of this twisting force, from the spider’s point of view, is unknown, researchers think the supercontraction in response to moisture may be a way to make sure a web is pulled tight in response to morning dew, perhaps protecting it from damage and maximizing its responsiveness to vibration for the spider to sense its prey.

“We haven’t found any biological significance” for the twisting motion, Buehler says. But through a combination of lab experiments and molecular modeling by computer, they have been able to determine how the twisting mechanism works. It turns out to be based on the folding of a particular kind of protein building block, called proline.

Investigating that underlying mechanism required detailed molecular modeling, which was carried out by Tarakanova and Hsu. “We tried to find a molecular mechanism for what our collaborators were finding in the lab,” Hsu explains. “And we actually found a potential mechanism,” based on the proline. They showed that with this particular proline structure in place, the twisting always occurred in the simulations, but without it there was no twisting.

“Spider dragline silk is a protein fiber,” Liu explains. “It’s made of two main proteins, called MaSp1 and MaSp2.” The proline, crucial to the twisting reaction, is found within MaSp2, and when water molecules interact with it they disrupt its hydrogen bonds in an asymmetrical way that causes the rotation. The rotation only goes in one direction, and it takes place at a threshold of about 70 percent relative humidity.

“The protein has a rotational symmetry built in,” Buehler says. And through its torsional force, it makes possible “a whole new class of materials.” Now that this property has been found, he suggests, maybe it can be replicated in a synthetic material. “Maybe we can make a new polymer material that would replicate this behavior,” Buehler says.

“Silk’s unique propensity to undergo supercontraction and exhibit a torsional behavior in response to external triggers such as humidity can be exploited to design responsive silk-based materials that can be precisely tuned at the nanoscale,” says Tarakanova, who is now an assistant professor at the University of Connecticut. “Potential applications are diverse: from humidity-driven soft robots and sensors, to smart textiles and green energy generators.”

It may also turn out that other natural materials exhibit this property, but if so this hasn’t been noticed. “This kind of twisting motion might be found in other materials that we haven’t looked at yet,” Buehler says. In addition to possible artificial muscles, the finding could also lead to precise sensors for humidity.

These researchers “have used silk’s known high sensitivity to humidity and demonstrated that it can also be used in an interesting way to create very precise torsional actuators,” says Yonggang Huang, a professor of civil and environmental engineering and mechanical engineering at Northwestern University, who was not involved in this work. “Using silk as a torsional actuator is a novel concept that could find applications in a variety of fields from electronics to biomedicine, for example, hygroscopic artificial muscles and humidity sensors,” he says.

Huang adds, “What is particularly noteworthy about this work is that it combines molecular modeling, experimental validation, and a deep understanding by which elementary changes in chemical bonding scale up into the macroscopic phenomena. This is very significant from a fundamental science point of view, and also exciting for applications.”

The work included collaborators at Huazhong University of Science and Technology and Hubei University, both in Wuhan, China, and Queen Mary University of London. It was supported by the National Natural Science Foundation of China, the National Science Foundation of Hubei Province, the Young Elite Scientist Sponsorship Program by CAST, the National Institutes of Health, the MIT Undergraduate Research Opportunities Program, and the Office of Naval Research.

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