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Thursday, February 9th, 2017
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Event |
| 6:00a |
New Center for Autism Research established at MIT’s McGovern Institute The McGovern Institute for Brain Research at MIT has announced the establishment of a new center dedicated to autism research. The center is made possible by a kick-off commitment of $20 million, made by Lisa Yang and MIT alumnus Hock Tan ’75 SM ’75.
The Hock E. Tan and K. Lisa Yang Center for Autism Research will support research on the genetic, biological, and neural bases of autism spectrum disorder, a developmental disability estimated to affect 1 in 68 individuals in the United States. Tan and Yang hope their initial investment will stimulate additional support and help foster collaborative research efforts to erase the devastating effects of this disorder on individuals, their families, and the broader autism community.
"With the Tan-Yang Center for Autism Research, we can imagine a world in which medical science understands and supports those with autism — and we can focus MIT's distinctive strengths on making that dream a reality. Lisa and Hock's gift reminds us of the impact we envision for the MIT Campaign for a Better World. I am grateful for their leadership and generosity, and inspired by the possibilities ahead," says MIT President L. Rafael Reif.
“I am thrilled to be investing in an institution that values a multidisciplinary collaborative approach to solving complex problems such as autism,” says Hock Tan, who graduated from MIT in 1975 with bachelor’s and master’s degrees in mechanical engineering. “We expect that successful research originating from our center will have a significant impact on the autism community.”
Originally from Penang, Malaysia, Tan has held several high-level finance and executive positions since leaving MIT. He is currently CEO of chipmaker Broadcom, Ltd.
Research at the Tan-Yang Center will focus on four major lines of investigation: genetics, neural circuits, novel autism models, and the translation of basic research to the clinical setting. By focusing research efforts on the origins of autism in our genes, in the womb and in the first years of life, the Tan-Yang Center aims to develop methods to better detect and potentially prevent autism spectrum disorders entirely. To help meet this challenge, the center will support collaborations across multiple disciplines — from genes to neural circuits — both within and beyond MIT.
“MIT has some of the world’s leading scientists studying autism,” says McGovern Institute Director Robert Desimone. “Support from the Tan-Yang Center will enable us to pursue exciting new directions that could not be funded by traditional sources. We will exploit revolutionary new tools, such as CRISPR and optogenetics, that are transforming research in neuroscience. We hope to not only identify new targets for medicines, but also develop novel treatments that are not based on standard pharmacological approaches. By supporting cutting-edge autism research here at MIT as well as our collaborative institutions, the center holds great promise to accelerate our basic understanding of this complex disorder.”
“Millions of families have been impacted by autism,” says Yang, a longtime advocate for the rights of individuals with disabilities and learning differences. “I am profoundly hopeful that the discoveries made at the Tan-Yang Center will have a long-term impact on the field of autism research and will provide fresh answers and potential new treatments for individuals affected by this disorder.” | | 2:00p |
Scientists estimate solar nebula’s lifetime About 4.6 billion years ago, an enormous cloud of hydrogen gas and dust collapsed under its own weight, eventually flattening into a disk called the solar nebula. Most of this interstellar material contracted at the disk’s center to form the sun, and part of the solar nebula’s remaining gas and dust condensed to form the planets and the rest of our solar system.
Now scientists from MIT and their colleagues have estimated the lifetime of the solar nebula — a key stage during which much of the solar system evolution took shape.
This new estimate suggests that the gas giants Jupiter and Saturn must have formed within the first 4 million years of the solar system’s formation. Furthermore, they must have completed gas-driven migration of their orbital positions by this time.
“So much happens right at the beginning of the solar system’s history,” says Benjamin Weiss, professor of earth, atmospheric, and planetary sciences at MIT. “Of course the planets evolve after that, but the large-scale structure of the solar system was essentially established in the first 4 million years.”
Weiss and MIT postdoc Huapei Wang, the first author of this study, report their results today in the journal Science. Their co-authors are Brynna Downey, Clement Suavet, and Roger Fu from MIT; Xue-Ning Bai of the Harvard-Smithsonian Center for Astrophysics; Jun Wang and Jiajun Wang of Brookhaven National Laboratory; and Maria Zucolotto of the National Museum in Rio de Janeiro.
Spectacular recorders
By studying the magnetic orientations in pristine samples of ancient meteorites that formed 4.653 billion years ago, the team determined that the solar nebula lasted around 3 to 4 million years. This is a more precise figure than previous estimates, which placed the solar nebula’s lifetime at somewhere between 1 and 10 million years.
The team came to its conclusion after carefully analyzing angrites, which are some of the oldest and most pristine of planetary rocks. Angrites are igneous rocks, many of which are thought to have erupted onto the surface of asteroids very early in the solar system’s history and then quickly cooled, freezing their original properties — including their composition and paleomagnetic signals — in place.
Scientists view angrites as exceptional recorders of the early solar system, particularly as the rocks also contain high amounts of uranium, which they can use to precisely determine their age.
“Angrites are really spectacular,” Weiss says. “Many of them look like what might be erupting on Hawaii, but they cooled on a very early planetesimal.”
Weiss and his colleagues analyzed four angrites that fell to Earth at different places and times.
“One fell in Argentina, and was discovered when a farm worker was tilling his field,” Weiss says. “It looked like an Indian artifact or bowl, and the landowner kept it by this house for about 20 years, until he finally decided to have it analyzed, and it turned out to be a really rare meteorite.”
The other three meteorites were discovered in Brazil, Antarctica, and the Sahara Desert. All four meteorites were remarkably well-preserved, having undergone no additional heating or major compositional changes since they originally formed.
Measuring tiny compasses
The team obtained samples from all four meteorites. By measuring the ratio of uranium to lead in each sample, previous studies had determined that the three oldest formed around 4.653 billion years ago. The researchers then measured the rocks’ remnant magnetization using a precision magnetometer in the MIT Paleomagnetism Laboratory.
“Electrons are little compass needles, and if you align a bunch of them in a rock, the rock becomes magnetized,” Weiss explains. “Once they’re aligned, which can happen when a rock cools in the presence of a magnetic field, then they stay that way. That’s what we use as records of ancient magnetic fields.”
When they placed the angrites in the magnetometer, the researchers observed very little remnant magnetization, indicating there was very little magnetic field present when the angrites formed.
The team went a step further and tried to reconstruct the magnetic field that would have produced the rocks’ alignments, or lack thereof. To do so, they heated the samples up, then cooled them down again in a laboratory-controlled magnetic field.
“We can keep lowering the lab field and can reproduce what’s in the sample,” Weiss says. “We find only very weak lab fields are allowed, given how little remnant magnetization is in these three angrites.”
Specifically, the team found that the angrites’ remnant magnetization could have been produced by an extremely weak magnetic field of no more than 0.6 microteslas, 4.653 billion years ago, or, about 4 million years after the start of the solar system.
In 2014, Weiss’ group analyzed other ancient meteorites that formed within the solar system’s first 2 to 3 million years, and found evidence of a magnetic field that was about 10-100 times stronger — about 5-50 microtesla.
“It’s predicted that once the magnetic field drops by a factor of 10-100 in the inner solar system, which we’ve now shown, the solar nebula goes away really quickly, within 100,000 years,” Weiss says. “So even if the solar nebula hadn’t disappeared by 4 million years, it was basically on its way out.”
The planets align
The researchers’ new estimate is much more precise than previous estimates, which were based on observations of faraway stars.
“What’s more, the angrites’ paleomagnetism constrains the lifetime of our own solar nebula, while astronomical observations obviously measure other faraway solar systems,” Wang adds. “Since the solar nebula lifetime critically affects the final positions of Jupiter and Saturn, it also affects the later formation of the Earth, our home, as well as the formation of other terrestrial planets.”
Now that the scientists have a better idea of how long the solar nebula persisted, they can also narrow in on how giant planets such as Jupiter and Saturn formed. Giant planets are mostly made of gas and ice, and there are two prevailing hypotheses for how all this material came together as a planet. One suggests that giant planets formed from the gravitational collapse of condensing gas, like the sun did. The other suggests they arose in a two-stage process called core accretion, in which bits of material smashed and fused together to form bigger rocky, icy bodies. Once these bodies were massive enough, they could have created a gravitational force that attracted huge amounts of gas to ultimately form a giant planet.
According to previous predictions, giant planets that form through gravitational collapse of gas should complete their general formation within 100,000 years. Core accretion, in contrast, is typically thought to take much longer, on the order of 1 to several million years. Weiss says that if the solar nebula was around in the first 4 million years of solar system formation, this would give support to the core accretion scenario, which is generally favored among scientists.
“The gas giants must have formed by 4 million years after the formation of the solar system,” Weiss says. “Planets were moving all over the place, in and out over large distances, and all this motion is thought to have been driven by gravitational forces from the gas. We’re saying all this happened in the first 4 million years.”
This research was supported, in part, by NASA and a generous gift from Thomas J. Peterson, Jr. | | 2:30p |
Secure wireless chargers Counterfeit chargers for portable electronics are a major problem. At the end of 2016, Apple claimed that of 100 Apple-branded charging accessories it bought on Amazon, 90 were counterfeits. Around the same time, Britain’s Chartered Trading Standards Institute reported that of 400 counterfeit chargers it bought from a range of online retailers, 397 failed a basic safety test.
In the last few years, portable electronics that can be recharged wirelessly have started coming to market. In an effort to get ahead of the problem of counterfeit wireless chargers — which could cause power surges that fry a device’s circuitry — researchers from MIT’s Microsystems Technology Laboratories have built a chip that blocks attempts to wirelessly charge a device’s battery unless the charger first provides cryptographic authentication.
The same technology also solves another problem with wireless chargers. When two devices share a single charger, if they are different distances from the charger’s electrical coil, their charging rates can vary enormously, to the extent that one device might charge fully while the other remains virtually uncharged. In the same way that the researchers’ chip can block power transfer from an unauthorized charger, it can slow the power transfer to a device nearer the charging coil, ensuring more equitable charge rates.
“Security is one of the most critical issues in the ‘internet of things [IoT],’” says Anantha Chandrakasan, the Vannevar Bush Professor of Electrical Engineering and Computer Science, referring to the popular idea that vehicles, appliances, civil-engineering structures, manufacturing equipment, and even livestock will soon have sensors that report information directly to networked servers. “We will see security functionality embedded into virtually every function and component of an IoT node.”
The researchers presented the new chip this week at the International Solid-State Circuits Conference. Chandrakasan is the senior author on the conference paper, and the first author is Nachiket Desai, who was an MIT graduate student in electrical engineering and computer science (EECS) when the work was done. They’re joined by Chiraag Juvekar, also an EECS graduate student at MIT, and Shubham Chandak, a graduate student in electrical engineering at Stanford University.
Switched out
In a wireless charging system, both the charger and the target device contain metal coils. An alternating current — an electrical current that changes direction at a regular rate — passing through the charger’s coil produces a magnetic field, which induces a current in the device’s coil. The rate at which the current in the charger alternates defines a frequency, much like the frequency of a radio transmission. The device’s coil must be “tuned” to the transmission frequency in order to receive power.
The MIT researchers’ chief innovation is a more compact and efficient circuit for tuning the frequency of the receiving coil. A standard tuning circuit connects the coil to a series of capacitors, electronic components that can store charge. Between each pair of capacitors is a switch, and switching capacitors on and off changes the receiver’s frequency.
“Those switches have very severe requirements,” Juvekar says. “They either have to block a very large voltage when they’re off, or they have to carry a very large current when they’re on, or in some cases both. If a switch needs to block a very big voltage, then it’s very hard to put that on the chip. So it has to be a discrete component on the [circuit] board, outside the chip. Or if it’s on the chip, it requires a specialized [manufacturing] process that might be very expensive.”
Instead of a single coil attached to a bank of capacitors, the MIT researchers’ design uses a pair of coils attached to one capacitor each — no switches required. “The fact that those switches aren’t there anymore is a big advantage,” Juvekar says.
Tuned in
In the researchers’ chip, one of the coils — the main coil — is much larger than the other — the auxiliary coil. The main coil carries the chief responsibility for charging a device’s battery. When a current is flowing through the auxiliary coil, it produces a magnetic field that changes the tuning frequency of the main coil.
In the circuit connected to the auxiliary coil, the resistance — the efficiency with which it conducts electricity — can be continuously varied. When the resistance is low, the auxiliary coil produces a strong magnetic field, which changes the main coil’s tuning frequency so drastically that charging is impossible.
When the resistance in the auxiliary coil’s circuit is higher, the magnetic field is weaker, and the detuning is less drastic. Some power transfer will still occur, but the charge rate is lower. That permits other, more distant devices to harvest more of the power transmitted by the charger coil.
The chip uses an authentication technique called elliptic curve cryptography, which is a “public-key” cryptographic technique. Using publicly available information, the chip can generate — and verify the response to — a question that only a charger with valid private information can answer. The chip doesn’t need to store a secret key of its own.
Elliptic curve cryptography is a well-established technique. But Chandrakasan’s group has developed a battery of methods for reducing chips’ power consumption, and the researchers found a way to simplify the encryption circuit so that it takes up less space on the chip and consumes less power.
“This paper describes an innovative approach to accurately and securely managing more than one wireless charging load,” says Baher Haroun, director of signal-path research at Texas Instruments’ Kilby Labs. “The need for security in wireless energy distribution is critical to ensure authorized and efficient use of the energy delivered. This work could have benefits for safety but also for [determining] ‘Who is a legitimate user for this delivered energy?’”
The work was sponsored by MIT Lincoln Labs, Texas Instruments, and the Taiwan Semiconductor Manufacturing Company, which manufactured the prototype chips through its University Shuttle program. | | 4:45p |
Government leaders gather at MIT to advance evidence-based policymaking State and local government leaders, leading scholars, and social service providers gathered in Cambridge on Jan. 12 and 13 to share their first-hand experiences creating and using rigorous evidence to address key challenges related to poverty. Participants focused on highlighting examples of how governments and researchers have partnered to use evidence from randomized evaluations to reduce crime and violence, improve maternal and child health, and promote housing mobility.
“Government leaders at all levels are increasingly turning to evidence to inform their policy decisions. Knowing what works best, what doesn’t, and why allows decision makers to implement policies that have a real and lasting impact and can help governments achieve budgetary savings,” said Melissa Kearney of the University of Maryland, co-chair of J-PAL North America’s State and Local Innovation Initiative.
J-PAL North America, which hosted the conference, is a regional office of MIT’s Abdul Latif Jameel Poverty Action Lab (J-PAL). J-PAL seeks to reduce poverty by ensuring that policy is informed by scientific evidence. Through the State and Local Innovation Initiative, J-PAL North America supports state and local governments in embedding randomized evaluations into social programs and using the results to inform their priority policy questions. The conference brought together the five governments selected to participate in the first year of the initiative — Philadelphia, Rochester, Pennsylvania, Puerto Rico, and South Carolina — along with other state and local government leaders and their research partners.
Evelyn Diaz of the Heartland Alliance and Sara Heller of the University of Pennsylvania shared their experience generating evidence to prevent crime and violence in Chicago. In response to rising homicide rates in the city, Diaz and Heller collaborated to design and carry out an evaluation of One Summer Chicago Plus, a program providing summer jobs to disadvantaged youth. The program led to a 43 percent decrease in violent crime arrests over 16 months. These results captured both municipal and federal attention, and the program is now on track to quadruple in size. "Just by doing a high-quality study, that also happened to have good results, we were able to make this program available to four times as many young people,” said Diaz. “That never happens in social services." Heller has used these lessons to inform new research, including an ongoing evaluation to test whether assigning participants an adult mentor is needed for the program to work.
A panel on using rigorous evidence to improve health outcomes for mothers and children featured an ongoing evaluation of the Nurse-Family Partnership’s flagship nurse home visiting program for low-income, first-time mothers and babies. Christian Soura of the South Carolina Department of Health and Human Services discussed the practical and political challenges of expanding this program through a pay-for-success contract — an exciting government strategy to fund social programs based on outcomes rather than inputs — and why evaluation is critical to the program’s long-term viability in South Carolina. Katherine Baicker of the Harvard T.H. Chan School of Public Health joined Soura to offer a researcher’s perspective on partnering with government to embed a randomized evaluation into program operations.
The final panel focused on leveraging housing vouchers as a ladder to economic mobility for low-income families. J-PAL North America co-scientific director Lawrence Katz of Harvard University and Gregory Russ of the Cambridge Housing Authority spoke on the seminal Moving to Opportunity experiment — a project launched by the U.S. Department of Housing and Urban Developing in 1994 to study the impact of randomly selecting low-income families to receive housing vouchers, some of which required families to move to low-poverty neighborhoods. A recent follow-up study found that children who moved before age 13 with a voucher that was restricted to low-poverty neighborhoods went to college at higher rates and had incomes that were 31 percent higher compared to their peers who did not receive a voucher. This research has spurred an innovative collaboration between 17 public housing authorities and researchers, called Creating Moves to Opportunity, to develop and implement new interventions focused on helping families move to higher opportunity areas.
The second day of the conference included a series of workshops during which academics, policymakers, and practitioners addressed some of the practical challenges of setting up new evaluations and shared lessons across jurisdictions.
J-PAL North America is currently accepting letters of interest for the second round of the J-PAL State and Local Innovation Initiative from governments interested in developing randomized evaluations and using the evidence generated to inform their decision-making. The deadline to submit letters of interest is Feb. 17. | | 6:05p |
Is the library the new public square? Is the library the new public square? That question is a core interest of the MIT Task Force on the Future of Libraries, which is re-imagining what libraries can and should be in a digital era when people still need intellectual communities and gathering places.
Preliminary findings blow the doors off of traditional concepts of libraries as enclosed spaces with physical objects under tight control. Now, the task force is seeking MIT community and alumni response by Feb. 15 before completing its report this spring.
“The report serves as a set of recommendations for moving the MIT Libraries towards the vision of a research library as an open global platform,” says Chris Bourg, director of MIT Libraries and the task force co-chair. “And it is an invitation to like-minded libraries, publishers, scholars, and others to join us in creating a more open, more productive, and more equitable information future.”
The new concept of libraries embraces a physical place plus services that provide access to materials such as ebooks, interactive scholarly materials, and images on multiple digital devices. Such resources — to be available on new interoperable content platforms — can make teaching and research more productive.
One reality the task force faces is that “the digital shift in libraries is nowhere near complete, and that, in fact, it has not gone nearly far enough,” Bourg says. “Today’s digital library suffers from what I call the 'not enough' problem.”
First, there is not enough digital content available, Bourg says. For example, only 8 percent of the Institute’s book collection and less than 40 percent of MIT theses are available in full text online. Second, not enough people have access to online materials because of publishers’ paywalls and bandwidth limitations. And third, there are not enough ways to access digital content; most is available to read but much less is open for text mining or interactive research.
10 recommendations
The 10 recommendations of the preliminary report's executive summary include the MIT Libraries redoubling efforts to preserve and disseminate MIT research. To do that, MIT needs to digitize as much of its original work as possible and make it available to an expanding worldwide audience.
“We want to build a digital library that is a global platform open to anyone who might want to build tools, search algorithms, or machine learning applications to use our collections in novel and productive ways, “ says Bourg.
What can community members do?
“We are interested in knowing what parts of the vision and recommendations most resonate with people,” says Bourg. “We are also interested in feedback on which ideas and recommendations [MIT community members and alumni] think would make the most impact in their professional and personal communities. And of course, we are interested in hearing from anyone who wants to partner with us to help us achieve this vision of using the library as an open global platform to facilitate more abundant and equitable access to knowledge and information.”
Community members can email recommendations the task force at future-lib@mit.edu by Feb. 15.
With final recommendations due out in the spring, the MIT Libraries has already convened a space planning group, which is led by Bourg and J. Meejin Yoon, professor and head of the Department of Architecture. Efforts are underway to seek funding for a research initiative, to set priorities, and to experiment with digitization and discovery tools. |
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