For first time, astronomers catch asteroid in the act of changing color

Last December, scientists discovered an “active” asteroid within the asteroid belt, sandwiched between the orbits of Mars and Jupiter. The space rock, designated by astronomers as 6478 Gault, appeared to be leaving two trails of dust in its wake — active behavior that is associated with comets but rarely seen in asteroids.

While astronomers are still puzzling over the cause of Gault’s comet-like activity, an MIT-led team now reports that it has caught the asteroid in the act of changing color, in the near-infrared spectrum, from red to blue. It is the first time scientists have observed a color-shifting asteroid, in real-time.

“That was a very big surprise,” says Michael Marsset, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “We think we have witnessed the asteroid losing its reddish dust to space, and we are seeing the asteroid’s underlying, fresh blue layers.”

Marsset and his colleagues have also confirmed that the asteroid is rocky — proof that the asteroid’s tail, though seemingly comet-like, is caused by an entirely different mechanism, as comets are not rocky but more like loose snowballs of ice and dust.

“It’s the first time to my knowledge that we see a rocky body emitting dust, a little bit like a comet,” Marsset says. “It means that probably some mechanism responsible for dust emission is different from comets, and different from most other active main-belt asteroids.”

Marsset and his colleagues, including EAPS Research Scientist Francesca DeMeo and Professor Richard Binzel, have published their results today in the journal Astrophysical Journal Letters.

A rock with tails

Astronomers first discovered 6478 Gault in 1988 and named the asteroid after planetary geologist Donald Gault. Until recently, the space rock was seen as relatively average, measuring about 2.5 miles wide and orbiting along with millions of other bits of rock and dust within the inner region of the asteroid belt, 214 million miles from the sun.

In January, images from various observatories, including NASA’s Hubble Space Telescope, captured two narrow, comet-like tails trailing the asteroid. Astronomers estimate that the longer tail stretches half a million miles out, while the shorter tail is about a quarter as long. The tails, they concluded, must consist of tens of millions of kilograms of dust, actively ejected by the asteroid, into space. But how? The question reignited interest in Gault, and studies since then have unearthed past instances of similar activity by the asteroid.

“We know of about a million bodies between Mars and Jupiter, and maybe about 20 that are active in the asteroid belt,” Marsset says. “So this is very rare.”

He and his colleagues joined the search for answers to Gault’s activity in March, when they secured observation time at NASA’s Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. Over two nights, they observed the asteroid and used a high-precision spectrograph to divide the asteroid’s incoming light into various frequencies, or colors, the relative intensities of which can give scientists an idea of an object’s composition.

From their analysis, the team determined that the asteroid’s surface is composed mainly of silicate, a dry, rocky material, similar to most other asteroids, and, more importantly, not at all like most comets.

Comets typically come from the far colder edges of the solar system. When they approach the sun, any surface ice instantly sublimates, or vaporizes into gas, creating the comet’s characteristic tail. Since Marsset’s team has found 6478 Gault is a dry, rocky body, this means it likely is generating dust tails by some other active mechanism.

A fresh change

As the team observed the asteroid, they discovered, to their surprise, that the rock was changing color in the near-infrared, from red to blue.

“We've never seen such a dramatic change like this over such a short period of time,” says co-author DeMeo.

The scientists say they are likely seeing the asteroid’s surface dust, turned red over millions of years of exposure to the sun, being ejected into space, revealing a fresh, less irradiated surface beneath, that appears blue at near-infrared wavelengths.

“Interestingly, you only need a very thin layer to be removed to see a change in the spectrum,” DeMeo says. “It could be as thin as a single layer of grains just microns deep.”

So what could be causing the asteroid to turn color? The team and other groups studying 6478 Gault believe the reason for the color shift, and the asteroid’s comet-like activity, is likely due to the same mechanism: a fast spin. The asteroid may be spinning fast enough to whip off layers of dust from its surface, through sheer centrifugal force. The researchers estimate it would need to have about a two-hour rotation period, spinning around every couple of hours, versus Earth’s 24-hour period.

“About 10 percent of asteroids spin very fast, meaning with a two- to three-hour rotation period, and it’s most likely due to the sun spinning them up,” says Marsset.

This spinning phenomenon is known as the YORP effect (or, the Yarkovsky-O’Keefe-Radzievskii-Paddack effect, named after the scientists who discovered it), which refers to the effect of solar radiation, or photons, on small, nearby bodies such as asteroids. While asteroids reflect most of this radiation back into space, a fraction of these photons is absorbed, then reemitted as heat, and also momentum. This creates a small force that, over millions of years, can cause the asteroid to spin faster.

Astronomers have observed the YORP effect on a handful of asteroids in the past. To confirm a similar effect is acting on 6478 Gault, researchers will have to detect its spin through light curves — measurements of the asteroid’s brightness over time. The challenge will be to see through the asteroid’s considerable dust tail, which can obscure key portions of the asteroid’s light.

Marsset’s team, along with other groups, plan to study the asteroid for further clues to activity, when it next becomes visible in the sky.

“I think [the group’s study] reinforces the fact that the asteroid belt is a really dynamic place,” DeMeo says. “While the asteroid fields you see in the movies, all crashing into each other, is an exaggeration, there is definitely a lot happening out there every moment.”

This research was funded, in part, by the NASA Planetary Astronomy Program.

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New science blooms after star researchers die, study finds

The famed quantum physicist Max Planck had an idiosyncratic view about what spurred scientific progress: death. That is, Planck thought, new concepts generally take hold after older scientists with entrenched ideas vanish from the discipline.

“A great scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it,” Planck once wrote.

Now a new study co-authored by MIT economist Pierre Azoulay, an expert on the dynamics of scientific research, concludes that Planck was right. In many areas of the life sciences, at least, the deaths of prominent researchers are often followed by a surge in highly cited research by newcomers to those fields.

Indeed, when star scientists die, their subfields see a subsequent 8.6 percent increase, on average, of articles by researchers who have not previously collaborated with those star scientists. Moreover, those papers published by the newcomers to these fields are much more likely to be influential and highly cited than other pieces of research.

“The conclusion of this paper is not that stars are bad,” says Azoulay, who has co-authored a new paper detailing the study’s findings. “It’s just that, once safely ensconsed at the top of their fields, maybe they tend to overstay their welcome.”

The paper, “Does Science Advance one Funeral at a Time?” is co-authored by Azoulay, the International Programs Professor of Management at the MIT Sloan School of Management; Christian Fons-Rosen, an assistant professor of economics at the University of California at Merced; and Joshua Graff Zivin, a professor of economics at the University of California at San Diego and faculty member in the university’s School of Global Policy and Strategy. It is forthcoming in the American Economic Review.

To conduct the study, the researchers used a database of life scientists that Azoulay and Graff Zivin have been building for well over a decade. In it, the researchers chart the careers of life scientists, looking at accomplishments that include funding awards, published papers and the citations of those papers, and patent statistics.

In this case, Azoulay, Graff Zivin, and Fons-Rosen studied what occurred after the unexpected deaths of 452 life scientists, who were still active in their disciplines. In addition to the 8.6 percent increase in papers by new entrants to those subfields, there was a 20.7 percent decrease in papers by the rather smaller number of scientists who had previously co-authored papers with the star scientists.

Overall, Azoulay notes, the study provides a window into the power structures of scientific disciplines. Even if well-established scientists are not intentionally blocking the work of researchers with alternate ideas, a group of tightly connected colleagues may wield considerable influence over journals and grant awards. In those cases, “it’s going to be harder for those outsiders to make a mark on the domain,” Azoulay notes.

“The fact that if you’re successful, you get to set the intellectual agenda of your field, that is part of the incentive system of science, and people do extraordinary positive things in the hope of getting to that position,” Azoulay notes. “It’s just that, once they get there, over time, maybe they tend to discount ‘foreign’ ideas too quickly and for too long.”

Thus what the researchers call “Planck’s Principle” serves as an unexpected — and tragic — mechanism for diversifying bioscience research.

The researchers note that in referencing Planck, they are extending his ideas to a slightly different setting than the one he himself was describing. In his writing, Planck was discussing the birth of quantum physics — the kind of epochal, paradigm-setting shift that rarely occurs in science. The current study, Azoulay notes, examines what happens in everyday “normal science,” in the phrase of philosopher Thomas Kuhn.

The process of bringing new ideas into science, and then hanging on to them, is only to be expected in many areas of research, according to Azoulay. Today’s seemingly stodgy research veterans were once themselves innovators facing an old guard.

“They had to hoist themselves atop the field in the first place, when presumably they were [fighting] the same thing,” Azoulay says. “It’s the circle of life.”

Or, in this case, the circle of life science.

The research received support from the National Science Foundation, the Spanish Ministry of Economy and Competitiveness, and the Severo Ochoa Programme for Centres of Excellence in R&D.

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MIT’s fleet of autonomous boats can now shapeshift

MIT’s fleet of robotic boats has been updated with new capabilities to “shapeshift,” by autonomously disconnecting and reassembling into a variety of configurations, to form floating structures in Amsterdam’s many canals.

The autonomous boats — rectangular hulls equipped with sensors, thrusters, microcontrollers, GPS modules, cameras, and other hardware — are being developed as part of the ongoing “Roboat” project between MIT and the Amsterdam Institute for Advanced Metropolitan Solutions (AMS Institute). The project is led by MIT professors Carlo Ratti, Daniela Rus, Dennis Frenchman, and Andrew Whittle. In the future, Amsterdam wants the roboats to cruise its 165 winding canals, transporting goods and people, collecting trash, or self-assembling into “pop-up” platforms — such as bridges and stages — to help relieve congestion on the city’s busy streets.

In 2016, MIT researchers tested a roboat prototype that could move forward, backward, and laterally along a preprogrammed path in the canals. Last year, researchers designed low-cost, 3-D-printed, one-quarter scale versions of the boats, which were more efficient and agile, and came equipped with advanced trajectory-tracking algorithms. In June, they created an autonomous latching mechanism that let the boats target and clasp onto each other, and keep trying if they fail.

In a new paper presented at the last week’s IEEE International Symposium on Multi-Robot and Multi-Agent Systems, the researchers describe an algorithm that enables the roboats to smoothly reshape themselves as efficiently as possible. The algorithm handles all the planning and tracking that enables groups of roboat units to unlatch from one another in one set configuration, travel a collision-free path, and reattach to their appropriate spot on the new set configuration.
In demonstrations in an MIT pool and in computer simulations, groups of linked roboat units rearranged themselves from straight lines or squares into other configurations, such as rectangles and “L” shapes. The experimental transformations only took a few minutes. More complex shapeshifts may take longer, depending on the number of moving units — which could be dozens — and differences between the two shapes.

“We’ve enabled the roboats to now make and break connections with other roboats, with hopes of moving activities on the streets of Amsterdam to the water,” says Rus, director of the Computer Science and Artificial Intelligence Laboratory (CSAIL) and the Andrew and Erna Viterbi Professor of Electrical Engineering and Computer Science. “A set of boats can come together to form linear shapes as pop-up bridges, if we need to send materials or people from one side of a canal to the other. Or, we can create pop-up wider platforms for flower or food markets.”

Joining Rus on the paper are: Ratti, director of MIT’s Senseable City Lab, and, also from the lab, first author Banti Gheneti, Ryan Kelly, and Drew Meyers, all researchers; postdoc Shinkyu Park; and research fellow Pietro Leoni.

Collision-free trajectories

For their work, the researchers had to tackle challenges with autonomous planning, tracking, and connecting groups of roboat units. Giving each unit unique capabilities to, for instance, locate each other, agree on how to break apart and reform, and then move around freely, would require complex communication and control techniques that could make movement inefficient and slow.

To enable smoother operations, the researchers developed two types of units: coordinators and workers. One or more workers connect to one coordinator to form a single entity, called a “connected-vessel platform” (CVP). All coordinator and worker units have four propellers, a wireless-enabled microcontroller, and several automated latching mechanisms and sensing systems that enable them to link together.

Coordinators, however, also come equipped with GPS for navigation, and an inertial measurement unit (IMU), which computes localization, pose, and velocity. Workers only have actuators that help the CVP steer along a path. Each coordinator is aware of and can wirelessly communicate with all connected workers. Structures comprise multiple CVPs, and individual CVPs can latch onto one another to form a larger entity.

During shapeshifting, all connected CVPs in a structure compare the geometric differences between its initial shape and new shape. Then, each CVP determines if it stays in the same spot and if it needs to move. Each moving CVP is then assigned a time to disassemble and a new position in the new shape.

Each CVP uses a custom trajectory-planning technique to compute a way to reach its target position without interruption, while optimizing the route for speed. To do so, each CVP precomputes all collision-free regions around the moving CVP as it rotates and moves away from a stationary one.

After precomputing those collision-free regions, the CVP then finds the shortest trajectory to its final destination, which still keeps it from hitting the stationary unit. Notably, optimization techniques are used to make the whole trajectory-planning process very efficient, with the precomputation taking little more than 100 milliseconds to find and refine safe paths. Using data from the GPS and IMU, the coordinator then estimates its pose and velocity at its center of mass, and wirelessly controls all the propellers of each unit and moves into the target location.

In their experiments, the researchers tested three-unit CVPs, consisting of one coordinator and two workers, in several different shapeshifting scenarios. Each scenario involved one CVP unlatching from the initial shape and moving and relatching to a target spot around a second CVP.

Three CVPs, for instance, rearranged themselves from a connected straight line — where they were latched together at their sides — into a straight line connected at front and back, as well as an “L.” In computer simulations, up to 12 roboat units rearranged themselves from, say, a rectangle into a square or from a solid square into a Z-like shape.

Scaling up

Experiments were conducted on quarter-sized roboat units, which measure about 1 meter long and half a meter wide. But the researchers believe their trajectory-planning algorithm will scale well in controlling full-sized units, which will measure about 4 meters long and 2 meters wide.

In about a year, the researchers plan to use the roboats to form into a dynamic “bridge” across a 60-meter canal between the NEMO Science Museum in Amsterdam’s city center and an area that’s under development. The project, called RoundAround, will employ roboats to sail in a continuous circle across the canal, picking up and dropping off passengers at docks and stopping or rerouting when they detect anything in the way. Currently, walking around that waterway takes about 10 minutes, but the bridge can cut that time to around two minutes.

“This will be the world’s first bridge comprised of a fleet of autonomous boats,” Ratti says. “A regular bridge would be super expensive, because you have boats going through, so you’d need to have a mechanical bridge that opens up or a very high bridge. But we can connect two sides of canal [by using] autonomous boats that become dynamic, responsive architecture that float on the water.”

To reach that goal, the researchers are further developing the roboats to ensure they can safely hold people, and are robust to all weather conditions, such as heavy rain. They’re also making sure the roboats can effectively connect to the sides of the canals, which can vary greatly in structure and design.

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Robotic thread is designed to slip through the brain’s blood vessels

MIT engineers have developed a magnetically steerable, thread-like robot that can actively glide through narrow, winding pathways, such as the labrynthine vasculature of the brain.

In the future, this robotic thread may be paired with existing endovascular technologies, enabling doctors to remotely guide the robot through a patient’s brain vessels to quickly treat blockages and lesions, such as those that occur in aneurysms and stroke.

“Stroke is the number five cause of death and a leading cause of disability in the United States. If acute stroke can be treated within the first 90 minutes or so, patients’ survival rates could increase significantly,” says Xuanhe Zhao, associate professor of mechanical engineering and of civil and environmental engineering at MIT. “If we could design a device to reverse blood vessel blockage within this ‘golden hour,’ we could potentially avoid permanent brain damage. That’s our hope.”

Zhao and his team, including lead author Yoonho Kim, a graduate student in MIT’s Department of Mechanical Engineering, describe their soft robotic design today in the journal Science Robotics. The paper’s other co-authors are MIT graduate student German Alberto Parada and visiting student Shengduo Liu.

In a tight spot

To clear blood clots in the brain, doctors often perform an endovascular procedure, a minimally invasive surgery in which a surgeon inserts a thin wire through a patient’s main artery, usually in the leg or groin. Guided by a fluoroscope that simultaneously images the blood vessels using X-rays, the surgeon then manually rotates the wire up into the damaged brain vessel. A catheter can then be threaded up along the wire to deliver drugs or clot-retrieval devices to the affected region.

Kim says the procedure can be physically taxing, requiring surgeons, who must be specifically trained in the task, to endure repeated radiation exposure from fluoroscopy.

“It’s a demanding skill, and there are simply not enough surgeons for the patients, especially in suburban or rural areas,” Kim says.

The medical guidewires used in such procedures are passive, meaning they must be manipulated manually, and are typically made from a core of metallic alloys, coated in polymer, a material that Kim says could potentially generate friction and damage vessel linings if the wire were to get temporarily stuck in a particularly tight space.

The team realized that developments in their lab could help improve such endovascular procedures, both in the design of the guidewire and in reducing doctors’ exposure to any associated radiation.

Threading a needle

Over the past few years, the team has built up expertise in both hydrogels — biocompatible materials made mostly of water — and 3-D-printed magnetically-actuated materials that can be designed to crawl, jump, and even catch a ball, simply by following the direction of a magnet.

In this new paper, the researchers combined their work in hydrogels and in magnetic actuation, to produce a magnetically steerable, hydrogel-coated robotic thread, or guidewire, which they were able to make thin enough to magnetically guide through a life-size silicone replica of the brain’s blood vessels.

The core of the robotic thread is made from nickel-titanium alloy, or “nitinol,” a material that is both bendy and springy. Unlike a clothes hanger, which would retain its shape when bent, a nitinol wire would return to its original shape, giving it more flexibility in winding through tight, tortuous vessels. The team coated the wire’s core in a rubbery paste, or ink, which they embedded throughout with magnetic particles.

Finally, they used a chemical process they developed previously, to coat and bond the magnetic covering with hydrogel — a material that does not affect the responsiveness of the underlying magnetic particles and yet provides the wire with a smooth, friction-free, biocompatible surface.

They demonstrated the robotic thread’s precision and activation by using a large magnet, much like the strings of a marionette, to steer the thread through an obstacle course of small rings, reminiscent of a thread working its way through the eye of a needle.

The researchers also tested the thread in a life-size silicone replica of the brain’s major blood vessels, including clots and aneurysms, modeled after the CT scans of an actual patient’s brain. The team filled the silicone vessels with a liquid simulating the viscosity of blood, then manually manipulated a large magnet around the model to steer the robot through the vessels’ winding, narrow paths.

Kim says the robotic thread can be functionalized, meaning that features can be added — for example, to deliver clot-reducing drugs or break up blockages with laser light. To demonstrate the latter, the team replaced the thread’s nitinol core with an optical fiber and found that they could magnetically steer the robot and activate the laser once the robot reached a target region.

When the researchers ran comparisons between the robotic thread coated versus uncoated with hydrogel, they found that the hydrogel gave the thread a much-needed, slippery advantage, allowing it to glide through tighter spaces without getting stuck. In an endovascular surgery, this property would be key to preventing friction and injury to vessel linings as the thread works its way through.

“One of the challenges in surgery has been to be able to navigate through complicated blood vessels in the brain, which has a very small diameter, where commercial catheters can’t reach,” says Kyujin Cho, assistant professor of mechanical engineering at Seoul National University. “This research has shown potential to overcome this challenge and enable surgical procedures in the brain without open surgery.”

And just how can this new robotic thread keep surgeons radiation-free? Kim says that a magnetically steerable guidewire does away with the necessity for surgeons to physically push a wire through a patient’s blood vessels. This means that doctors also wouldn’t have to be in close proximity to a patient, and more importantly, the radiation-generating fluoroscope.

In the near future, he envisions endovascular surgeries that incorporate existing magnetic technologies, such as pairs of large magnets, the directions of which doctors can manipulate from just outside the operating room, away from the fluoroscope imaging the patient’s brain, or even in an entirely different location.

“Existing platforms could apply magnetic field and do the fluoroscopy procedure at the same time to the patient, and the doctor could be in the other room, or even in a different city, controlling the magnetic field with a joystick,” Kim says. “Our hope is to leverage existing technologies to test our robotic thread in vivo in the next step.”

This research was funded, in part, by the Office of Naval Research, the MIT Institute for Soldier Nanotechnologies, and the National Science Foundation (NSF).

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MIT engineers build advanced microprocessor out of carbon nanotubes

After years of tackling numerous design and manufacturing challenges, MIT researchers have built a modern microprocessor from carbon nanotube transistors, which are widely seen as a faster, greener alternative to their traditional silicon counterparts.

The microprocessor, described today in the journal Nature, can be built using traditional silicon-chip fabrication processes, representing a major step toward making carbon nanotube microprocessors more practical.

Silicon transistors — critical microprocessor components that switch between 1 and 0 bits to carry out computations — have carried the computer industry for decades. As predicted by Moore’s Law, industry has been able to shrink down and cram more transistors onto chips every couple of years to help carry out increasingly complex computations. But experts now foresee a time when silicon transistors will stop shrinking, and become increasingly inefficient.

Making carbon nanotube field-effect transistors (CNFET) has become a major goal for building next-generation computers. Research indicates CNFETs have properties that promise around 10 times the energy efficiency and far greater speeds compared to silicon. But when fabricated at scale, the transistors often come with many defects that affect performance, so they remain impractical.

The MIT researchers have invented new techniques to dramatically limit defects and enable full functional control in fabricating CNFETs, using processes in traditional silicon chip foundries. They demonstrated a 16-bit microprocessor with more than 14,000 CNFETs that performs the same tasks as commercial microprocessors. The Nature paper describes the microprocessor design and includes more than 70 pages detailing the manufacturing methodology.

The microprocessor is based on the RISC-V open-source chip architecture that has a set of instructions that a microprocessor can execute. The researchers’ microprocessor was able to execute the full set of instructions accurately. It also executed a modified version of the classic “Hello, World!” program, printing out, “Hello, World! I am RV16XNano, made from CNTs.”

“This is by far the most advanced chip made from any emerging nanotechnology that is promising for high-performance and energy-efficient computing,” says co-author Max M. Shulaker, the Emanuel E Landsman Career Development Assistant Professor of Electrical Engineering and Computer Science (EECS) and a member of the Microsystems Technology Laboratories. “There are limits to silicon. If we want to continue to have gains in computing, carbon nanotubes represent one of the most promising ways to overcome those limits. [The paper] completely re-invents how we build chips with carbon nanotubes.”

Joining Shulaker on the paper are: first author and postdoc Gage Hills, graduate students Christian Lau, Andrew Wright, Mindy D. Bishop, Tathagata Srimani, Pritpal Kanhaiya, Rebecca Ho, and Aya Amer, all of EECS; Arvind, the Johnson Professor of Computer Science and Engineering and a researcher in the Computer Science and Artificial Intelligence Laboratory; Anantha Chandrakasan, the dean of the School of Engineering and the Vannevar Bush Professor of Electrical Engineering and Computer Science; and Samuel Fuller, Yosi Stein, and Denis Murphy, all of Analog Devices.

Fighting the “bane” of CNFETs

The microprocessor builds on a previous iteration designed by Shulaker and other researchers six years ago that had only 178 CNFETs and ran on a single bit of data. Since then, Shulaker and his MIT colleagues have tackled three specific challenges in producing the devices: material defects, manufacturing defects, and functional issues. Hills did the bulk of the microprocessor design, while Lau handled most of the manufacturing.

For years, the defects intrinsic to carbon nanotubes have been a “bane of the field,” Shulaker says. Ideally, CNFETs need semiconducting properties to switch their conductivity on an off, corresponding to the bits 1 and 0. But unavoidably, a small portion of carbon nanotubes will be metallic, and will slow or stop the transistor from switching. To be robust to those failures, advanced circuits will need carbon nanotubes at around 99.999999 percent purity, which is virtually impossible to produce today.  

The researchers came up with a technique called DREAM (an acronym for “designing resiliency against metallic CNTs”), which positions metallic CNFETs in a way that they won’t disrupt computing. In doing so, they relaxed that stringent purity requirement by around four orders of magnitude — or 10,000 times — meaning they only need carbon nanotubes at about 99.99 percent purity, which is currently possible.

Designing circuits basically requires a library of different logic gates attached to transistors that can be combined to, say, create adders and multipliers — like combining letters in the alphabet to create words. The researchers realized that the metallic carbon nanotubes impacted different pairings of these gates differently. A single metallic carbon nanotube in gate A, for instance, may break the connection between A and B. But several metallic carbon nanotubes in gates B may not impact any of its connections.

In chip design, there are many ways to implement code onto a circuit. The researchers ran simulations to find all the different gate combinations that would be robust and wouldn’t be robust to any metallic carbon nanotubes. They then customized a chip-design program to automatically learn the combinations least likely to be affected by metallic carbon nanotubes. When designing a new chip, the program will only utilize the robust combinations and ignore the vulnerable combinations.

“The ‘DREAM’ pun is very much intended, because it’s the dream solution,” Shulaker says. “This allows us to buy carbon nanotubes off the shelf, drop them onto a wafer, and just build our circuit like normal, without doing anything else special.”

Exfoliating and tuning

CNFET fabrication starts with depositing carbon nanotubes in a solution onto a wafer with predesigned transistor architectures. However, some carbon nanotubes inevitably stick randomly together to form big bundles — like strands of spaghetti formed into little balls — that form big particle contamination on the chip.  

To cleanse that contamination, the researchers created RINSE (for “removal of incubated nanotubes through selective exfoliation”). The wafer gets pretreated with an agent that promotes carbon nanotube adhesion. Then, the wafer is coated with a certain polymer and dipped in a special solvent. That washes away the polymer, which only carries away the big bundles, while the single carbon nanotubes remain stuck to the wafer. The technique leads to about a 250-times reduction in particle density on the chip compared to similar methods.

Lastly, the researchers tackled common functional issues with CNFETs. Binary computing requires two types of transistors: “N” types, which turn on with a 1 bit and off with a 0 bit, and “P” types, which do the opposite. Traditionally, making the two types out of carbon nanotubes has been challenging, often yielding transistors that vary in performance. For this solution, the researchers developed a technique called MIXED (for “metal interface engineering crossed with electrostatic doping”), which precisely tunes transistors for function and optimization.

In this technique, they attach certain metals to each transistor — platinum or titanium — which allows them to fix that transistor as P or N. Then, they coat the CNFETs in an oxide compound through atomic-layer deposition, which allows them to tune the transistors’ characteristics for specific applications. Servers, for instance, often require transistors that act very fast but use up energy and power. Wearables and medical implants, on the other hand, may use slower, low-power transistors.  

The main goal is to get the chips out into the real world. To that end, the researchers have now started implementing their manufacturing techniques into a silicon chip foundry through a program by Defense Advanced Research Projects Agency, which supported the research. Although no one can say when chips made entirely from carbon nanotubes will hit the shelves, Shulaker says it could be fewer than five years. “We think it’s no longer a question of if, but when,” he says.

The work was also supported by Analog Devices, the National Science Foundation, and the Air Force Research Laboratory.

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Ultrathin 3-D-printed films convert energy of one form into another

MIT researchers have developed a simple, low-cost method to 3-D print ultrathin films with high-performing “piezoelectric” properties, which could be used for components in flexible electronics or highly sensitive biosensors.

Piezoelectric materials produce a voltage in response to physical strain, and they respond to a voltage by physically deforming. They’re commonly used for transducers, which convert energy of one form into another. Robotic actuators, for instance, use piezoelectric materials to move joints and parts in response to an electrical signal. And various sensors use the materials to convert changes in pressure, temperature, force, and other physical stimuli, into a measurable electrical signal.

Researchers have been trying for years to develop piezoelectric ultrathin films that can be used as energy harvesters, sensitive pressure sensors for touch screens, and other components in flexible electronics. The films could also be used as tiny biosensors that are sensitive enough to detect the presence of molecules that are biomarkers for certain diseases and conditions.

The material of choice for those applications is often a type of ceramic with a crystal structure that resonates at high frequencies due to its extreme thinness. (Higher frequencies basically translate to faster speeds and higher sensitivity.) But, with traditional fabrication techniques, creating ceramic ultrathin films is a complex and expensive process.

In a paper recently published in the journal Applied Materials and Interfaces, the MIT researchers describe a way to 3-D print ceramic transducers about 100 nanometers thin by adapting an additive manufacturing technique for the process that builds objects layer by layer, at room temperature. The films can be printed in flexible substrates with no loss in performance, and can resonate at around 5 gigahertz, which is high enough for high-performance biosensors.

“Making transducing components is at the heart of the technological revolution,” says Luis Fernando Velaśquez-García, a researcher in the Microsystems Technology Laboratories (MTL) in the Department of Electrical Engineering and Computer Science. “Until now, it’s been thought 3-D-printed transducing materials will have poor performances. But we’ve developed an additive fabrication method for piezoelectric transducers at room temperature, and the materials oscillate at gigahertz-level frequencies, which is orders of magnitude higher than anything previously fabricated through 3-D printing.”

Joining Velaśquez-García on the paper is first author Brenda García-Farrera of MTL and the Monterrey Institute of Technology and Higher Education in Mexico.

Electrospraying nanoparticles

Ceramic piezoelectric thin films, made of aluminum nitride or zinc oxide, can be fabricated through physical vapor deposition and chemical vapor deposition. But those processes must be completed in sterile clean rooms, under high temperature and high vacuum conditions. That can be a time-consuming, expensive process.

There are lower-cost 3-D-printed piezoelectric thin films available. But those are fabricated with polymers, which must be “poled”— meaning they must be given piezoelectric properties after they’re printed. Moreover, those materials usually end up tens of microns thick and thus can’t be made into ultrathin films capable of high-frequency actuation.

The researchers’ system adapts an additive fabrication technique, called near-field electrohydrodynamic deposition (NFEHD), which uses high electric fields to eject a liquid jet through a nozzle to print an ultrathin film. Until now, the technique has not been used to print films with piezoelectric properties.

The researchers’ liquid feedstock — raw material used in 3-D printing — contains zinc oxide nanoparticles mixed with some inert solvents, which forms into a piezoelectric material when printed onto a substrate and dried. The feedstock is fed through a hollow needle in a 3-D printer. As it prints, the researchers apply a specific bias voltage to the tip of the needle and control the flow rate, causing the meniscus — the curve seen at the top of a liquid — to form into a cone shape that ejects a fine jet from its tip.

The jet is naturally inclined to break into droplets. But when the researchers bring the tip of the needle close to the substrate — about a millimeter — the jet doesn’t break apart. That process prints long, narrow lines on a substrate. They then overlap the lines and dry them at about 76 degrees Fahrenheit, hanging upside down.

Printing the film precisely that way creates an ultrathin film of crystal structure with piezoelectric properties that resonates at about 5 gigahertz. “If anything of that process is missing, it doesn’t work,” Velaśquez-García says.

Using microscopy techniques, the team was able to prove that the films have a much stronger piezoelectric response — meaning the measurable signal it emits — than films made through traditional bulk fabrication methods. Those methods don’t really control the film’s piezoelectric axis direction, which determines the material’s response. “That was a little surprising,” Velaśquez-García says. “In those bulk materials, they may have inefficiencies in the structure that affect performance. But when you can manipulate materials at the nanoscale, you get a stronger piezoelectric response.”

Low-cost sensors

Because the piezoelectric ultrathin films are 3-D printed and resonate at very high frequencies, they can be leveraged to fabricate low-cost, highly sensitive sensors. The researchers are currently working with colleagues in Monterrey Tec as part of a collaborative program in nanoscience and nanotechnology, to make piezoelectric biosensors to detect biomarkers for certain diseases and conditions.

A resonating circuit is integrated into these biosensors, which makes the piezoelectric ultrathin film oscillate at a specific frequency, and the piezoelectric material can be functionalized to attract certain molecule biomarkers to its surface. When the molecules stick to the surface, it causes the piezoelectric material to slightly shift the frequency oscillations of the circuit. That small frequency shift can be measured and correlated to a certain amount of the molecule that piles up on its surface.

The researchers are also developing a sensor to measure the decay of electrodes in fuel cells. That would function similarly to the biosensor, but the shifts in frequency would correlate to the degradation of a certain alloy in the electrodes. “We’re making sensors that can diagnose the health of fuel cells, to see if they need to be replaced,” Velaśquez-García says. “If you assess the health of these systems in real time, you can make decisions about when to replace them, before something serious happens.”

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Overcoming obstacles with an electric hovercraft

Through dedication and a willingness to face challenges both expected and unforeseen, an MIT team recently brought the air-powered hovercraft from the world of Saturday-morning cartoons to reality, at the 2019 SpaceX Hyperloop Pod Competition.

But that’s only part of the story.

What’s past is prologue

In a 2013 white paper, Elon Musk, technology entrepreneur, investor, and engineer, detailed a high-speed frictionless train — the Hyperloop. When drag and atmosphere were removed from a tunnel, he posited, trains could float within a vacuum tube at up to 700 miles per hour.

Musk wasn’t the first to imagine an air-powered train. In the 1860s, Alfred Ely Beach, inventor, publisher, and patent lawyer, envisioned a subway under the streets of New York City. In 1870, his experiments in pneumatic power resulted in a demonstration run of the Beach Pneumatic Transit, a 10-passenger car propelled by a 100-horsepower fan, baffles, and blowers, through a tunnel beneath Broadway. His efforts were thwarted by Tammany Hall politics and the Panic of 1873.

It took the MIT team, dubbed Hyperloop II, to once more embrace Beach’s concept. “We took Beach’s vision and accomplished a much more efficient pneumatic vehicle,” explains Vik Parthiban, team captain.

Lofty goals

Parthiban, a graduate researcher at the MIT Media Lab, was part of the 2017 SpaceX Hyperloop Pod Competition during his undergraduate years at the University of Texas. He came to MIT determined to further the technology and, in the fall of 2018, recruited nearly 30 undergraduate and graduate students to develop an autonomous electric hovercraft.

“Imagine an air hockey puck,” explains Parthiban. “Instead of air coming out of a table, it comes out of pucks under the vehicle. A regulation system pumps air into these air castors, which then levitate the vehicle.” Four castors beneath the vehicle are operated by a pneumatic system controlled by a central computer. The propulsion system takes the 200-kilogram vehicle from zero to 200 miles per hour in 20 seconds with the push of a finger.

High-speed passenger trains in China and Japan use magnetic levitation to create a gap between the train and the track to remove the drag, but Parthiban took a different approach. “Putting magnetic levitation in a hyperloop is expensive,” he says. “Our goal was to invent a new technology that would cost less and be more efficient than magnetic levitation, and to develop an electric hovercraft that would work even without a vacuum tunnel. The only thing needed is a flat surface.”

The process

With support from the Edgerton Center and industry sponsors including Arrow Electronics, Silicon Expert, and Texas Guadaloop, the group joined forces to contribute individual skills. “We worked together to figure out the best way to integrate the components. Every person brought their own knowledge,” says Nick Dowmon, software engineering lead and a System Design and Management (SDM) graduate student. “It was an awesome learning opportunity and a chance to collaborate and learn from each other.”

Over the winter, the team met in the Edgerton Center’s build space to create a machine no one had ever built before. They brainstormed, designed, and redesigned. They machined parts, outsourcing the more complex components. They collaborated with the University of Texas on pneumatics and conducted analyses to determine the type of sensors needed to levitate and propel the pod at the required speed, adjusting here, fine-tuning there. They fashioned the 70-component wiring harness and constructed a test track in a 200-foot-long corridor beneath MIT’s Great Dome.

On May 22, the completed pod was presented at the MIT Museum to an overflow crowd eager to view the world’s first electric hovercraft.

A minor setback

In early summer, the production schedule was on target. Team members were confident the pod would meet its delivery deadline and reach California by July 7. On June 18, Parthiban and two teammates bent over the pod in the build space, intent upon working out last-minute details.

Then Parthiban saw flames. A tear in the battery insulation had caused a short, and he reached for a fire extinguisher. But the blaze quickly escalated, he recalls, and he reached for the fire alarm instead.

“The battery insulation fire burned down most of the vehicle,” he says. “It was the saddest thing.”

Parthiban called an emergency team meeting that evening, and within two hours, every team member had arrived — including those who’d left the project to focus on research and internships. Parthiban explained that rebuilding the pod in three weeks was virtually impossible.

But in true MIT style, every team member came together in a resounding “Let’s do this!”

“Everyone agreed we had to make it happen,” says Bowen Zeng, levitation lead and a graduate student in mechanical engineering. “There was no choice.”

“We had to drop everything to rebuild the pod before we went to California,” says Dowmon. “Many times, I was still in the build space at midnight with someone that I didn’t normally work with toiling on a part of the pod, but we helped each other. We worked through it together.”

Three days after the meeting, the pneumatic panel was rebuilt. In a week, the new chassis was finished. The electronic systems were recreated. Sponsors fast-tracked the delivery of replacement components. And a week before the shipping deadline, the pod was finished (again).

“I don’t think I’ve ever worked with a team that was so dedicated, so able to keep on going after something so discouraging,” adds Jessica Harsono, braking team lead and graduate student in mechanical engineering.

MIT’s entry was the only fully-functioning levitating pod in the competition at SpaceX headquarters in July. “Competition week was truly where our collaboration paid off,” says Parthiban. “With only a few people in California, we had to split the tasks and get parts and do the machining in a short amount of time, under deadline. But we made it.”

The MIT team emerged as the No. 1 U.S. university at the annual competition and placed fifth worldwide. They also earned a SpaceX Innovation award.

Only at MIT

Beach laid the groundwork and Musk provided the opportunity, but in the end, it was the spirit of camaraderie and teamwork that made the MIT team’s hyperloop a reality.

“My motivation wasn’t that I wanted to achieve this for myself,” says Harsono. “So many other people worked so hard, and I didn’t want to let them down. I was motivated out of respect for what they’d done and how much effort and care they put in.”

“This only can happen at MIT,” Parthiban says. “We all have that same mindset, the same hard-work attitude.”

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Health, wealth, and cities

Cities have wealth disparities: Picture fancy downtown condos and trendy shopping areas in contrast to, say, streets with rundown housing and boarded-up shops. Cities also have health disparities: People who live in well-off parts of metro areas are less exposed to many of the pollutants, risks, and stresses that lead to long-term health problems.

The health issues are easier to overlook, partly because they are less visible. We don’t necessarily see the factors that create health inequities, such as particulates from freeway pollution that settle in low-income neighborhoods, the lead pipes causing cognitive problems in people who drink from them, the added stress of being poor, or the lack of access to health care that exacerbates other problems for low-income people.

Still, the health gap in cities is real and demands significant scholarly attention. Enter Mariana Arcaya, an associate professor in MIT’s Department of Urban Studies and Planning (DUSP). Arcaya is a specialist in urban health issues, with a broad research portfolio.

Arcaya has studied the health effects of efforts such as the federal Moving to Opportunity program, which relocated families within metropolitan areas (with mixed health effects). She has also examined issues as diverse as the health impact of foreclosure, the considerable prevalence of posttraumatic stress among New Orleans residents displaced by Hurricane Katrina, and even the impact of public transportation on health.

“The human body is so sensitive to environmental and social conditions,” Arcaya notes. “The neighborhoods people live in help determine what we’re exposed to.”

Arcaya has also found that families in Moving to Opportunity program were less likely to move if they already had a sick child. Thus low-income families were, to an extent, trapped by health problems in economically deprived neighborhoods, which themselvs can harm health.

But if Arcaya’s research interests are complex, the moral foundations of her work are simple.

“We should be aiming for cities that are supportive of human health for everyone, rich or poor, and of any race or ethnicity,” says Arcaya.

“All kids should be born into a society where everyone has a fair shot of growing up healthy,” she continues. “When you’re saddled from the beginning with avoidable health problems caused by where you live, those can limit your potential, and that’s unfair.”

That ethical vision has long motived her work, since her days as a school student. Now, for her research and teaching, she has just been awarded tenure at MIT.

“What I’m doing is what I always thought I wanted to be doing,” Arcaya says. “I’m interested in how inequality in place-based opportunity follows people throughout their lives and sets people on different paths, in part by affecting their health.”

Arcaya, who grew up just outside of New York City, has long had a keen interest in environmental issues — “I ran for president of my middle school on basically an environmental platform,” she says, laughing — and in college at Duke University she majored in environmental science and policy. There, she learned about the health problems that environmental degradation can cause — but not necessarily about what to do in response. So she earned an MCP at MIT, from DUSP, focusing on city planning and health.

“A lot of the health problems I was studying stemmed from the built environment, and the way we disregarded the value of the natural environment,” Arcaya says. “I came to MIT to focus on the equity implications of trying to enact change: How do you intervene in a positive way?”

After completing her MIT master’s thesis, Arcaya then earned a PhD at Harvard University’s T.H. Chan School of Public Health, which helped build her public health knowledge and sharpen her scholarly tool kit. At this point — having studied the environment, cities, and health — Arcaya went on the academic job market, while starting a family. She joined the MIT faculty in 2015.

“I gave my job talk eight months pregnant, took advantage of parental leave after the birth of my second child, and bring my kids to work if they’re sent home from daycare sick,” Arcaya says. “Lots of working parents deal with everything from pregnancy discrimination to a lack of paid parental leave, which is simply wrong. I’ve only been able to do my job because I’ve had the benefit of an incredibly supportive environment and great policies.”

Arcaya has been engaged in multiple ambitious projects during her time at the Institute. Over the last couple of years, she has also intensified her interest in setting up long-term study programs that aim to reveal new, in-depth information about cities and health.

One of these, the Healthy Neighborhoods Study, is an in-depth quantitative and qualitative look at nine neighborhoods in Boston, taking what Arcaya calls “a resident-centered approach” to identifying public health problems.

Another is a long-term study of mothers in New Orleans recovering from Hurricane Katrina, extending some of Arcaya’s earlier work about posttraumatic stress. In this project as well, Arcaya and her research partners are collecting information about the life tradeoffs Katrina survivors have made, to understand what Arcaya calls the “realistic complexity” of the issue. 

“Disasters have always been a part of life, but the severity and number are expected to go up,” Arcaya says. “What are we going to do about that? How can we expect individuals to respond, and how can we adapt?”

And as income and wealth inequality rises in the U.S., Arcaya has also become an advocate urging urban planners and scholars to develop studies that will further explore the inequities of urban conditions.

“We have become increasingly unequal socioeconomically in this country, which compounds some of the new and worsensing environmental threats we face,” Arcaya says. “That needs to factor into our research on neighborhods and health. Good planning may be one of the most effective public health tools we have.”

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Ramona Allen named vice president for human resources

Ramona Allen, who has served the Institute for 30 years in a variety of progressively senior human resources roles, has been named as MIT’s next vice president for human resources.

Allen, currently assistant dean for human resources in the School of Architecture and Planning (SA+P), will begin her new role on Oct. 1. Her appointment was announced today by Executive Vice President and Treasurer Israel Ruiz in an email to MIT faculty and staff.

“Ramona brings a deep appreciation and understanding of the MIT organization and culture, broad experience as a strategic thinker and creative problem solver, a collaborative and approachable management style, and exceptional leadership skills,” Ruiz wrote. “She has demonstrated a sustained dedication to MIT and an unwavering commitment to our community.”

Allen joined MIT in 1989 and has served since then in a variety of human resources roles. During her tenure, she has served as an advisor to three SA+P deans and to the leadership of a number of departments, labs, and centers across campus.

“After three decades, I am still inspired and excited about the work that happens at MIT,” Allen says. “People are our most valuable resource. It’s the role of HR — along with the faculty and staff who lead MIT’s departments, labs, centers, and other units ­— to recognize and make individuals feel valued and a true part of this community. I am honored to return to MIT Human Resources to work with the talented and committed professionals who work quietly behind the scenes to support life at MIT.”

Allen will report to Ruiz, with a dotted-line connection to Provost Martin Schmidt. In his letter, Ruiz thanked Deputy Executive Vice President Anthony Sharon, who has led MIT Human Resources on an interim basis since the departure of Lorraine Goffe, MIT’s former vice president for human resources, at the end of 2018.

Before coming to the Institute, Allen spent nine years working at Harvard Community Health Plan. Her first position at MIT, from 1989 to 1995, was as a personnel officer in MIT Human Resources, supporting the interdisciplinary research centers and laboratories under the vice president for research. Beginning in 1995, Allen served as human resources administrator in the Department of Biology; she joined the MIT Media Lab as its first director of human resources in 2001.

In 2004, Allen assumed additional responsibilities for human resources activities across the Media Lab’s home school, SA+P. She was appointed as SA+P’s first director of human resources in 2008 and was promoted to assistant dean for human resources in 2013.

“At once transformative and stabilizing, Ramona Allen brings a humane perspective to every aspect of human resources,” says Hashim Sarkis, dean of the MIT School of Architecture and Planning.

As SA+P’s top human resources official, Allen has:

• Created a wellness program, sponsored by the SA+P dean, with plans to expand following the school’s expected move into the Metropolitan Storage Warehouse.
• Engaged SA+P interns from the Year Up, Boston program — an intensive, one-year training program that provides talented and motivated underserved young adults with a combination of skills development, coursework for college credit, corporate internships, and support.
• Helped create an organizational design and structure, working with faculty, for two new research and academic units: the Leventhal Center for Advanced Urbanism and the Program in Art, Culture and Technology. 
• Selected a new information system to manage search processes for hiring faculty in SA+P.

Through her many roles over 30 years at MIT, Ruiz wrote, Allen’s experience has extended to many facets of human resources, including employee relations, labor relations, compensation, promotion and tenure processes, and training programs. She has developed flexible and creative workplace structures and diversity and inclusion plans.

“I have the greatest enthusiasm for the many contributions I know Ramona will continue to make to the Institute,” Ruiz wrote in his letter to MIT faculty and staff.

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Chris Caplice appointed MIT senior research scientist

Chris Caplice PhD ’96, executive director of the MIT Center for Transportation and Logistics, has been appointed MIT senior research scientist for his long-term commitment to research and education in supply chain management. Over the past two decades, Caplice has developed and deployed theoretical models and educational innovations that have had a global impact on supply chain practice and education. In 2016, Caplice was named a Silver Family Research Fellow and became the only nonfaculty member at MIT to receive an endowed chair.

Most recently, Dr. Chris (as his online learners refer to him) was recognized for innovations in education both online and on campus. From the MITx Prize for Teaching and Learning with MOOCs to the Irwin Sizer Award for Most Significant Improvement to MIT Education to the student-nominated MIT Teaching with Digital Technology Award, Caplice has been repeatedly recognized for his contributions to supply-chain education. He created and led the first-ever MicroMasters credential program to be offered anywhere. More than a quarter of a million people from 196 different countries have enrolled in one or more of his courses. Over 1,500 learners have completed the full credential, and more than 10,000 are in the pipeline to complete it. This credential is being recognized across sectors for its value and relevance to improving supply chain management competency worldwide.

“Chris’s work has truly advanced the online learning experience — not only for courses in supply chain management, but also for others inspired by his example,” says Sanjay Sarma, MIT vice president for open learning.

Previously, Caplice directed the MIT Master of Engineering in Logistics. He transformed the program from a purely technical and analytics-focused degree to one that includes leadership and management training. Today, this boutique MIT master’s program in its 20th year has over 750 alumni working in leadership roles in some of the world’s largest organizations. His master’s format has served as the foundation for the MIT Global SCALE Network graduate certificate now offered to hundreds of students annually through five collaborating institutions worldwide. 

Pioneering education is only Caplice’s most recent contribution to the supply-chain sector and business at large. Beginning right after his MIT PhD, Caplice applied optimization-based procurement models he had studied to create OptiBid. This tool was the first ever to apply combinatorial auctions to freight transportation. Since that time, optimization-based procurement has become an industry-standard practice and is embedded in all professional-grade transportation management systems. Later, while chief scientist at Chainalytics, Caplice developed an econometric pricing model that uncovered hidden costs in shipper-carrier policies. He introduced the parameters of this model in 2004 to a consortium of would-be competitors and collaborators. Aggregating and anonymizing the information allowed these companies and organizations to gain better market information without sharing any confidential material. Today, an unexpected benefit from this work is a “regional freight value” for every three-digit postal code in the United States, widely used by firms to allocate distribution, manufacturing, and other facilities.

Research discoveries in supply chain management may not gather headlines in the same way they do in other disciplines; even so, their impact on daily lives is significant. Caplice’s applied research has influenced daily life in many hidden ways. During the 2000s, he developed scenario-planning models to deliver long-range transportation and infrastructure methodology as part of the Future Freight Flows project. Today, the methodology is used by transportation departments in many U.S. states and has changed the way many agencies interact with the private sector in terms of long-term infrastructure needs. More recently, working with the world’s largest retailer, Caplice designed a stochastic optimization tool that helps them make the best assignment decisions for their fleet and for-hire carriers. This has led to annual savings for the company in the tens of millions of dollars. In addition, it reduced the company’s planning investment time by 75 percent. While these kinds of breakthroughs may not be obvious to the end user, they impact the capability of companies and organizations to create and deliver goods and services that the public can use. 

The challenges to supply chains and their management will continue to mount as our societies become more concentrated in globally connected urban environments. Building on past innovations and serving as executive director of the Center for Transportation and Logistics will position Caplice to continue to exert an analytical and practical approach to new challenges for practitioners. As a senior research scientist, he is empowered to manage a diverse portfolio of research and education activities.

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A warm reception for the Class of 2023

With audible enthusiasm, students in the Class of 2023 and their families gathered under a tent in front of Kresge Auditorium on Monday at one of the first events of orientation week, the annual President’s Convocation for the first-year students.

President L. Rafael Reif introduced the crowd to MIT’s top leadership and recalled his own experiences when he first arrived at this campus, 2,000 miles north of his home in Caracas, Venezuela. “I was excited when I got to campus, but I was also anxious,” he said.

Coming from a place whose average annual temperatures vary from 72 to 75 degrees, he said, he “had a lot to learn about boots, winter jackets, and the art of layering.” And, like many people arriving at this campus for the first time, he said, “I wasn’t sure if I had what it would take to succeed.” But those fears were quickly dispelled, he added.

What he soon discovered, was “a community of students, faculty, researchers, and staff who were a lot like me — they loved to ask questions, they were passionate, they loved to tinker. Many of them came from someplace else. And they cared about helping each other and about helping society.” And, he added, “this is still the MIT I know today.”

Reif said that “here on this campus, I found my home. So no matter where you come from, I’m here to welcome you to your new home!”

That new home will undoubtedly produce both highs and lows, he said, adding, “You will enjoy great moments of success, but you may also experience moments of doubt.” He offered three pieces of advice to remember when those moments of doubt arrive.

First, he said, “You belong here!” MIT Dean of Admissions Stuart Schmill ’86 “has a remarkable knack for finding the right students for each year’s incoming class. You’re here because you belong here. Do not forget that.”

Second, “all of us experience doubts about ourselves — even the distinguished professors here on stage. Very often those doubts come out when you are trying something new or are pushing yourself. … Just remember, if you have doubts about yourself, it’s just a sign that you are learning.”

Finally, he said, “You are surrounded by a community that cares about you. All of us are dedicated to your success, and we believe in you. If you need help, please ask. Everybody, everybody needs help sometimes.”

Reif then introduced three professors who are also alumni, and who shared stories of their own early days at MIT. John Fernandez, class of ’85 and now director of the Environmental Solutions Initiative (ESI), led off by describing his three different arrivals at MIT. When he first arrived as an undergraduate, he wondered, “How will I relate to so many different people with so many different interests?” As a first-generation American whose parents had arrived from Latin America, he recalled, “I had so many questions.”

After earning his graduate degrees elsewhere, he returned 17 years later to join the faculty. “Being part of the MIT faculty is a total dream job,” he said, “because we get to teach and learn and work with MIT undergraduates.” His third new arrival experience came in 2015, when he and his wife moved into Baker House as heads of house. They soon mastered the initially bewildering array of acronyms and course numbers that are sprinkled throughout the language of the MIT community. Now, he says, “my wife and I now both speak really good MIT.” Each of those three times, he said, he learned that “you change a place when you arrive, by the decisions you make and the good graces of your actions.”

Fernandez then asked the new students to broaden their horizons. “Become a more effective MIT student, whatever major you choose, by learning deeply about human values, ethics, and their philosophical and social foundations” he said. “Learn these things from the experts. … MIT’s future and the world’s partly depends on it, and your future will be better for it.”

In addition, he said, “Ask a question of yourself: Now that you have arrived at MIT, what will you do about climate change?” Whether by joining one of many student groups, working with ESI, or through academic research, this is an issue that everyone needs to take on in a serious way, he said. “Go build the MIT the world needs and deserves,” he said, “because now you are MIT, and MIT is you.”

Julie Shah ’04, SM ’06, PhD ’11, an associate professor of aeronautics and astronautics, said that in her experience MIT “pushes you to be your best personally and academically, but you never had to do it on your own.” Faculty members and fellow students are always there to help.

Shah said, “People sometimes ask how I manage in such a competitive place,” but she found that in fact, people at the Institute are not competing with each other but rather competing to simply do the best they possibly can. “The only danger in asking a question here is that your friend or colleague or professor might spend an hour, or many hours, telling you everything they know about a topic.”

While many people talk about learning to juggle the many demands of life at MIT, Shah took the advice quite literally: “I spent I can’t tell you how many hours in Lobby 7 watching the juggling club,” she recalled. Shah then learned to juggle, and realized how crucial it is to pay attention to maintaining a balanced view — if you focus too much on just one ball, “the whole thing falls apart,” she said. The same applies to balancing the parts of one’s life, including the academic and the extracurricular: “It’s important to have a hobby that you really love, outside of your coursework.”

Marin Soljacic ’96, now a professor of physics, recalled arriving at MIT as a student from Croatia, never having been to the United States before. “I was surprised by quite a few things,” he said. One of those was the requirement to take eight classes in the humanities and social sciences in order to graduate. While he was initially skeptical, he said, “those ended up being some of my favorite classes,” and led to enduring friendships.

Describing the difference between classical mechanics and quantum mechanics, both of which he teaches classes on, Soljacic related a time when his wife was searching for her keys. Under classical mechanics, he explained, “things are always exactly where one leaves them. It’s quite remarkable when you think about it.” By contrast, in the world of quantum mechanics, the keys could quantum tunnel unpredictably to an entirely different place. According to his wife, this is a typical example of MIT humor.

Soljacic said that in traveling around the world, people often ask him to describe what is the special strength of MIT. “We have some money,” he said, but so do many other places. “We also have some great equipment,” but so do other institutions. “Our main strength really is people,” he said. “We have the best people in the world. And from this day forward, this includes you also, the best undergraduates in the world.”

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The Engine expands, responding to rapid growth of “tough tech”

The Engine announced today that it will create an additional 200,000 square feet of shared office, fabrication, and lab space in Cambridge, Massachusetts, to further foster “tough tech” — transformative technology that takes the long view, solving the world’s important challenges through the convergence of breakthrough science, engineering, and leadership.

The Engine, built by MIT, invests in early-stage tough-tech companies. These companies have long been underserved by the traditional investment ecosystem, leaving many breakthrough ideas stuck in the lab. A new model of venture capital firm, The Engine has provided dozens of forward-looking entrepreneurs with critical access to capital, industry know-how, and specialized equipment through its 28,000-square-foot location at 501 Massachusetts Avenue in Central Square, Cambridge.

The expansion, in collaboration with MIT, will extend and amplify the progress of the thriving innovation ecosystem in Cambridge and the greater Boston region. Central to the effort will be the renovation of the existing building at 750 Main Street to serve as a new hub for tough-tech growth, with the capacity to accommodate approximately 100 companies and 800 entrepreneurs. The initiative will accelerate the development of next-generation technology by providing the vital infrastructure and resources necessary to accommodate fast-growing startups throughout the region.

This new hub will provide a place for companies to put their ideas into action — helping them build transformative technologies as efficiently, economically, and effectively as possible. It will have a natural proximity to academic institutions; access to talent; flexible and affordable lab and fabrication facilities; and a network that will foster relationships for market readiness. It aims to connect the diverse tough-tech ecosystem — entrepreneurs, scientists, engineers, leaders in academia and business, investors, and policymakers. The space will be specifically designed for companies at the convergence of technology disciplines across engineering and physical sciences, where access to diverse space and tools are essential for success. This expansion demonstrates MIT’s ongoing commitment to investing in and anchoring the evolving innovation ecosystem in and around Kendall Square.

The Engine launched its portfolio in 2017 with investments in seven tough-tech companies. It has since invested in 12 additional tough-tech founding teams, bringing its current portfolio to 19 companies. Together, those companies have raised approximately $285 million in capital and employ more than 200 people. 

“We have a rare opportunity to help cultivate the next generation of leaders tackling the world’s most urgent, challenging problems,” says Katie Rae, CEO and managing partner of The Engine. “We also have the chance to forge a foundational infrastructure that can potentially change the geography of innovation. A thriving hub can propel the Boston region into the future as a magnet for world-changing companies in tough tech.”

Since its founding in 2016, The Engine has pioneered a new framework for investing in and supporting tough tech startups working on transformative technologies — ranging from commercial fusion power and ultra-efficient semiconductors to next-generation cell therapies and new manufacturing methods for metals, among others. This framework clears a path to commercialization for companies by providing capital, infrastructure (labs, equipment, office space, and more), and a support network. In October 2018, hundreds of members of The Engine’s network of companies and supporters joined forces in the Boston area at the first annual Tough Tech Summit.

“It’s thrilling to witness the revolutionary work coming out of The Engine,” says Israel Ruiz, executive vice president and treasurer at MIT. “The model appears to be working just as we had hoped: The direct access to key infrastructure, enabling investment, and support services is helping game-changing innovators to accelerate their work in order to more rapidly address consequential and challenging pursuits. The new expanded space will allow The Engine, and its companies, to significantly increase its local and global impact.”

The design for the 750 Main Street building renovation is slated to be finalized in 2019, with construction scheduled to begin later this year. The Engine’s new space will be complemented by active ground floor uses that will contribute to a more animated streetscape.

Once situated in its expanded location, The Engine will continue to invest in areas such as advanced manufacturing, advanced materials, energy, food and agriculture, space, semiconductors, the internet of things, quantum computing, biotech, artificial intelligence, robotics, and the intersection of new technologies.

MIT continues to play a leading role in fostering innovation and research in and around the MIT campus through its Kendall Square Initiative, which will create a vibrant multiuse district with new buildings, open space, and gathering spaces, and will be home to innovative companies, retail, and restaurants. This tough-tech hub will be a new center for The Engine, and a focal point of the innovation ecosystem inspired and cultivated by MIT.

For more information about The Engine, please see its first report for the period 2016 -2018.

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Jesús Dones-Monroig: Creating space for everyone in chemistry

Growing up on a large swath of land in Puerto Rico, Jesús Dones-Monroig was always playing in nature. He was encouraged to plant, build, and explore the environment around his home. His father even took him to the ocean to go spearfishing, where he developed a fascination for marine life. He credits a lot of his curiosity of nature to his parents, who encouraged Dones-Monroig and his siblings to play outdoors.

“[My parents] let us be free to do whatever we wanted out there. They gave us the freedom to have an idea and play with things outside to make it happen,” says Dones-Monroig.

Eventually, this affinity with the natural world would contribute to Dones-Monroig’s interest in biology and organic chemistry. He went on to study chemistry at the University of Puerto Rico at Rio Piedras and was particularly inspired by his organic chemistry professor, Ingrid Montes, to appreciate the world through a molecular level.

Now a fifth year PhD student in the Department of Chemistry, Dones-Monroig works in the lab of Ronald Raines, the Roger and Georges Firmenich Professor of Natural Product Chemistry, and studies collagen mimetic peptides, or “CMPs.” Dones-Monroig has developed a CMP that can selectively anneal with damaged collagen. At this stage, he is working on optimizing his newly developed CMP to help detect mammalian collagen that has suffered damage. In the future, he hopes to develop a system that selectively anneals to different types of damaged collagen.

As a chemical biologist, Dones-Monroig also works on synthetic chemistry projects, from developing synthetic peptides through organic chemistry to synthesizing faster and more selective organic molecules for “click chemistry.”  

“That’s why I love research in the Raines Lab,” Dones-Monroig says, “You’re not restricted to one area of chemistry.”

Promoting diversity and inclusion

Dones-Monroig is a family-driven, community-oriented person, and being so far from home has motivated him to create connections and support groups at MIT. He also feels strongly that without the right support, students can’t fully realize their potential in their academic and professional pursuits.

While pursuing his masters in chemical biology at the University of Wisconsin at Madison, Dones-Monroig was involved in programs that promote diversity and inclusion. Coming to MIT, he felt there was a lack of support for underrepresented and underserved graduate and undergraduate students at the Institute. With the help of professor and former head of the Department of Chemistry Tim Jamison, as well as individuals in the Women in Chemistry (WIC) group and the Chemistry Graduate Student Committee (CGSC), Dones-Monroig founded the Chemistry Alliance for Diversity and Inclusion (CADI).

Launched in 2018, CADI seeks to support the success of underrepresented and underserved graduate and undergraduate students in the chemistry department and to help ensure that the campus has safe, inclusive, and supportive environments for students. The group facilitates conversations regarding the state of diversity in the field of chemistry and provides students with professional and academic resources. Finding community in graduate school can be just as important as the classes one takes or the skills one acquires, Dones-Monroig says.

“If we are not given support at a personal level, our educational and professional potential is going to be directly affected. CADI is for anybody that doesn’t feel part of the chemistry department,” he says.

Dones-Monroig also serves as a pod leader for the MIT Summer Research Program (MSRP), a program that aims to promote the value of graduate education and improve the research enterprise through increased diversity in MIT.

“The students that come to this program are astounding. They’re very intelligent and driven, but they may not have the same resources as MIT in their home universities. So we welcome them,” says Dones-Monroig.

Continuing with his penchant for mentorship, Dones-Monroig will serve as a graduate resident advisor (GRA) at the MIT Student House. He will be a mentor to the international undergraduate and graduate students that live there.

Healthy bodies, healthy minds

Outside of his research, Dones-Monroig stays quite active and enjoys sports. He plays on MIT’s intramural basketball team, and he also enjoys volleyball, tennis, and surfing. Perhaps most impressively, he participates in the Spartan Races, which are races that range in length and feature a variety of physical obstacles. Next month, he will be doing an Ultra-Spartan Race on Killington Peak in Vermont, where he will go through 60 obstacles over the course of 30 miles.

For Dones-Monroig, exercise allows him to reduce stress and focus on something other than his research. He attributes his good health, mentally and physically, to staying active. This mentality is from his 61-year-old father, who still tries to run races against him, Dones-Monroig jokes.

“If you have a mindset of keeping your body as healthy as your mind, you’ll be more productive. I train my mind in the lab and come out and train my body outside,” says Dones-Monroig.

While Dones-Monroig clearly works hard, he plays hard too, and loves to dance salsa on the weekends. With friends that he has made in the local Puerto Rican community, Dones-Monroig goes out to dance and socialize at La Fábrica in Central Square.

“I think I’m decent at salsa,” Dones-Monroig laughs, adding, “When compared to non-salsa dancers, then I’m good!”

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IBM gives artificial intelligence computing at MIT a lift

IBM designed Summit, the fastest supercomputer on Earth, to run the calculation-intensive models that power modern artificial intelligence (AI). Now MIT is about to get a slice. 

IBM pledged earlier this year to donate an $11.6 million computer cluster to MIT modeled after the architecture of Summit, the supercomputer it built at Oak Ridge National Laboratory for the U.S. Department of Energy. The donated cluster is expected to come online this fall when the MIT Stephen A. Schwarzman College of Computing opens its doors, allowing researchers to run more elaborate AI models to tackle a range of problems, from developing a better hearing aid to designing a longer-lived lithium-ion battery. 

“We’re excited to see a range of AI projects at MIT get a computing boost, and we can’t wait to see what magic awaits,” says John E. Kelly III, executive vice president of IBM, who announced the gift in February at MIT’s launch celebration of the MIT Schwarzman College of Computing.  

IBM has named the cluster Satori, a Zen Buddhism term for “sudden enlightenment.” Physically the size of a shipping container, Satori is intellectually closer to a Ferrari, capable of zipping through 2 quadrillion calculations per second. That’s the equivalent of each person on Earth performing more than 10 million multiplication problems each second for an entire year, making Satori nimble enough to join the middle ranks of the world’s 500 fastest computers.

Rapid progress in AI has fueled a relentless demand for computing power to train more elaborate models on ever-larger datasets. At the same time, federal funding for academic computing facilities has been on a three-decade decline. Christopher Hill, director of MIT’s Research Computing Project, puts the current demand at MIT at five times what the Institute can offer.  

“IBM’s gift couldn’t come at a better time,” says Maria Zuber, a geophysics professor and MIT’s vice president of research. “The opening of the new college will only increase demand for computing power. Satori will go a long way in helping to ease the crunch.”

The computing gap was immediately apparent to John Cohn, chief scientist at the MIT-IBM Watson AI Lab, when the lab opened last year. “The cloud alone wasn’t giving us all that we needed for challenging AI training tasks,” he says. “The expense and long run times made us ask, could we bring more compute power here, to MIT?”

It’s a mission Satori was built to fill, with IBM Power9 processors, a fast internal network, a large memory, and 256 graphics processing units (GPUs). Designed to rapidly process video-game images, graphics processors have become the workhorse for modern AI applications. Satori, like Summit, has been configured to wring as much power from each GPU as possible.

IBM’s gift follows a history of collaborations with MIT that have paved the way for computing breakthroughs. In 1956, IBM helped launch the MIT Computation Center with the donation of an IBM 704, the first mass-produced computer to handle complex math. Nearly three decades later, IBM helped fund Project Athena, an initiative that brought networked computing to campus. Together, these initiatives spawned time-share operating systems, foundational programming languages, instant messaging, and the network-security protocol, Kerberos, among other technologies. 

More recently, IBM agreed to invest $240 million over 10 years to establish the MIT-IBM Watson AI Lab, a founding sponsor of MIT’s Quest for Intelligence. In addition to filling the computing gap at MIT, Satori will be configured to allow researchers to exchange data with all major commercial cloud providers, as well as prepare their code to run on IBM’s Summit supercomputer.

Josh McDermott, an associate professor at MIT’s Department of Brain and Cognitive Sciences, is currently using Summit to develop a better hearing aid, but before he and his students could run their models, they spent countless hours getting the code ready. In the future, Satori will expedite the process, he says, and in the longer term, make more ambitious projects possible.

“We’re currently building computer systems to model one sensory system but we’d like to be able to build models that can see, hear and touch,” he says. “That requires a much bigger scale.”

Richard Braatz, the Edwin R. Gilliland Professor at MIT’s Department of Chemical Engineering, is using AI to improve lithium-ion battery technologies. He and his colleagues recently developed a machine learning algorithm to predict a battery’s lifespan from past charging cycles, and now, they’re developing multiscale simulations to test new materials and designs for extending battery life. With a boost from a computer like Satori, the simulations could capture key physical and chemical processes that accelerate discovery. “With better predictions, we can bring new ideas to market faster,” he says. 

Satori will be housed at a silk mill-turned data center, the Massachusetts Green High Performance Computing Center (MGHPCC) in Holyoke, Massachusetts, and connect to MIT via dedicated, high-speed fiber optic cables. At 150 kilowatts, Satori will consume as much energy as a mid-sized building at MIT, but its carbon footprint will be nearly fully offset by the use of hydro and nuclear power at the Holyoke facility. Equipped with energy-efficient cooling, lighting, and power distribution, the MGHPCC was the first academic data center to receive LEED-platinum status, the highest green-building award, in 2011.

“Siting Satori at Holyoke minimizes its carbon emissions and environmental impact without compromising its scientific impact,” says John Goodhue, executive director of the MGHPCC.

Visit the Satori website for more information.

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Two studies reveal benefits of mindfulness for middle school students

Two new studies from MIT suggest that mindfulness — the practice of focusing one’s awareness on the present moment — can enhance academic performance and mental health in middle schoolers. The researchers found that more mindfulness correlates with better academic performance, fewer suspensions from school, and less stress.

“By definition, mindfulness is the ability to focus attention on the present moment, as opposed to being distracted by external things or internal thoughts. If you’re focused on the teacher in front of you, or the homework in front of you, that should be good for learning,” says John Gabrieli, the Grover M. Hermann Professor in Health Sciences and Technology, a professor of brain and cognitive sciences, and a member of MIT’s McGovern Institute for Brain Research.

The researchers also showed, for the first time, that mindfulness training can alter brain activity in students. Sixth-graders who received mindfulness training not only reported feeling less stressed, but their brain scans revealed reduced activation of the amygdala, a brain region that processes fear and other emotions, when they viewed images of fearful faces.

Together, the findings suggest that offering mindfulness training in schools could benefit many students, says Gabrieli, who is the senior author of both studies. 

“We think there is a reasonable possibility that mindfulness training would be beneficial for children as part of the daily curriculum in their classroom,” he says. “What’s also appealing about mindfulness is that there are pretty well-established ways of teaching it.”

In the moment

Both studies were performed at charter schools in Boston. In one of the papers, which appears today in the journal Behavioral Neuroscience, the MIT team studied about 100 sixth-graders. Half of the students received mindfulness training every day for eight weeks, while the other half took a coding class. The mindfulness exercises were designed to encourage students to pay attention to their breath, and to focus on the present moment rather than thoughts of the past or the future.

Students who received the mindfulness training reported that their stress levels went down after the training, while the students in the control group did not. Students in the mindfulness training group also reported fewer negative feelings, such as sadness or anger, after the training.

About 40 of the students also participated in brain imaging studies before and after the training. The researchers measured activity in the amygdala as the students looked at pictures of faces expressing different emotions.

At the beginning of the study, before any training, students who reported higher stress levels showed more amygdala activity when they saw fearful faces. This is consistent with previous research showing that the amygdala can be overactive in people who experience more stress, leading them to have stronger negative reactions to adverse events.

“There’s a lot of evidence that an overly strong amygdala response to negative things is associated with high stress in early childhood and risk for depression,” Gabrieli says.

After the mindfulness training, students showed a smaller amygdala response when they saw the fearful faces, consistent with their reports that they felt less stressed. This suggests that mindfulness training could potentially help prevent or mitigate mood disorders linked with higher stress levels, the researchers say.

Richard Davidson, a professor of psychology and psychiatry at the University of Wisconsin, says that the findings suggest there could be great benefit to implementing mindfulness training in middle schools.

“This is really one of the very first rigorous studies with children of that age to demonstrate behavioral and neural benefits of a simple mindfulness training,” says Davidson, who was not involved in the study.

Evaluating mindfulness

In the other paper, which appeared in the journal Mind, Brain, and Education in June, the researchers did not perform any mindfulness training but used a questionnaire to evaluate mindfulness in more than 2,000 students in grades 5-8. The questionnaire was based on the Mindfulness Attention Awareness Scale, which is often used in mindfulness studies on adults. Participants are asked to rate how strongly they agree with statements such as “I rush through activities without being really attentive to them.”

The researchers compared the questionnaire results with students’ grades, their scores on statewide standardized tests, their attendance rates, and the number of times they had been suspended from school. Students who showed more mindfulness tended to have better grades and test scores, as well as fewer absences and suspensions.

“People had not asked that question in any quantitative sense at all, as to whether a more mindful child is more likely to fare better in school,” Gabrieli says. “This is the first paper that says there is a relationship between the two.”

The researchers now plan to do a full school-year study, with a larger group of students across many schools, to examine the longer-term effects of mindfulness training. Shorter programs like the two-month training used in the Behavioral Neuroscience study would most likely not have a lasting impact, Gabrieli says.

“Mindfulness is like going to the gym. If you go for a month, that’s good, but if you stop going, the effects won’t last,” he says. “It’s a form of mental exercise that needs to be sustained.”

The research was funded by the Walton Family Foundation, the Poitras Center for Psychiatric Disorders Research at the McGovern Institute for Brain Research, and the National Council of Science and Technology of Mexico. Camila Caballero ’13, now a graduate student at Yale University, is the lead author of the Mind, Brain, and Education study. Caballero and MIT postdoc Clemens Bauer are lead authors of the Behavioral Neuroscience study. Additional collaborators were from the Harvard Graduate School of Education, Transforming Education, Boston Collegiate Charter School, and Calmer Choice.

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What’s the best way to cut vehicle greenhouse-gas emissions?

Policies to encourage reductions in greenhouse gas emissions tend to stress the need to switch as many vehicles as possible to electric power. But a new study by MIT and the Ford Motor Company finds that depending on the location, in some cases an equivalent or even bigger reduction in emissions could be achieved by switching to lightweight conventional (gas-powered) vehicles instead — at least in the near term.

The study looked at a variety of factors that can affect the relative performance of these vehicles, including the role of low temperatures in reducing battery performance, regional differences in average number of miles driven annually, and the different mix of generating sources in different parts of the U.S. The results are being published today in the journal Environmental Science & Technology, in a paper by MIT Principal Research Scientist Randolph Kirchain, recent graduate Di Wu PhD ’18, graduate student Fengdi Guo, and three researchers from Ford.

The study combined a variety of datasets to examine the relative impact of different vehicle choices down to a county-by-county level across the nation. It showed that while electric vehicles provide the greatest impact in reducing greenhouse gas emissions for most of the country, especially on both coasts and in the south, significant parts of the Midwest had the opposite result, with lightweight gasoline-powered vehicles achieving a greater reduction.

The biggest factor leading to that conclusion was the mix of generating sources going into the grid in different regions, Kirchain says. That mix is “cleaner” on both the East and West coasts, with higher usage of renewable energy sources and relatively low-emissions natural gas, while in the upper Midwest there is still a much higher proportion of coal-burning power plants. That means that even though electric vehicles produce no greenhouse emissions while they are being driven, the process of recharging the car’s batteries results in significant emissions.

In those locations, buying a lightweight car, defined as one whose structure is built largely from aluminum or specialized lightweight steel, would actually result in fewer emissions than buying a comparable electric car, the study found.

The research was made possible by Ford’s collection of vehicle-performance data from about 30,000 cars, over a total of about 300 million miles of driving. They come from conventional midsize conventional gasoline cars, and the researchers used standard modeling techniques to calculate the performance of equivalent vehicles that were either hybrid-electric, battery-electric, or lightweight versions of conventional cars.

 “We tried to add as much spatial resolution as possible, compared to other studies in the literature, to try to get a sense of the combined effects” of the various factors of temperature, the grid, and driving conditions, Kirchain explains. That combination of data showed, among other things, that “some of the areas with more carbon-heavy grids also happen to be colder, and somewhat more rural,” he says. “All three of those things can tilt emissions in a negative way for electric vehicles” in terms of their impact on reducing emissions. The combined effects are strongest in parts of Wisconsin and Michigan, where lightweight cars would have a significant advantage over EVs in reducing emissions, the study showed.

The impact of cold weather on battery performance, he says, “is something that is discussed in the EV literature, but not as much in the popular discussions of the topic.” Conversely, gasoline-powered vehicles suffer an efficiency penalty in urban driving, but they have lower emissions in regions that are more rural and spread out.

The data on car performance the team had to work with thanks to their collaboration with Ford researchers “was unique,” Kirchain says. “In the past, a ‘large’ study of this type would be a few dozen vehicles,” and those would mainly come from people who volunteered to share their data and therefore were more likely to be concerned about environmental impact. The extensive Ford data, by contrast, provide “a broader cross-section of drivers and driving conditions.”

Kirchain stresses that the intent of this study is not in any way to minimize the importance of switching over ground transportation to electric power in order to curb greenhouse emissions. “We’re not trying to undermine the fact that electrification is the long-term solution — and the short-term solution for most of the country,” he says. But over the next few decades, which is considered a critical period in determining the planet’s climate outcomes, it’s important to know what measures will actually be most effective in reducing carbon emissions in order to set policies and incentives that will produce the best outcomes, he says.

The relative advantage of lightweight vehicles compared to electric ones, according to their modeling, “goes down over time, as the grid improves,” he says. “But it doesn’t go away completely until you get to close to 2050 or so.”

Lightweight aluminum is now used in the Ford F-150 pickup truck, and in the all-electric Tesla sedans. Currently, there are no high-volume lightweight gasoline-powered midsize cars on the market in the U.S., but they could be built if incentives similar to those used to encourage the production of electric cars were in place, Kirchain suggests.

Right now, he says, the U.S. has “a patchwork of regulations and incentives that are providing extra incentives for electrification.” But there are certain parts of the country, he says, where it would make more sense to provide incentives “for any option that provides sufficient fuel savings, not just for electrification,” he says.

“At least for the north central part of the country, policymakers should consider a more nuanced approach,” he adds.

“This is a significant advance,” says Heather MacLean, professor of civil and mineral engineering at the University of Toronto, who was not associated with this work. This study, she says, “illustrates the importance of the regional disaggregation in the analysis, and that if it were absent results would be incorrect. This is an unequivocal call for regional policies that use the latest research to build rational agendas, rather than prescribing overarching global solutions.”

The research team included Robert De Kleine, Hyung Chul Kim, and Timothy Wallington of the Research and Innovation Center of Ford Motor Company, in Dearborn, Michigan.

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