Category Archives: Student research

Many natural composite materials have evolved to wrinkle in response to certain stimuli: The eye of the squid is lined with wavy layers of silvery reflectors that give it a silvery sheen. In the cell walls of many plants, wrinkles allow expansion without strain. Finally, the inner lining of arteries contain wrinkled lamellae that can be indicators of coronary heart disease, and can serve as markers for the condition.

Given these examples from nature, scientists say that understanding the mechanisms by which materials internally wrinkle could help in creating new, responsive materials for use in chemical sensing, medical diagnostics and optical and acoustic wave control.

Now researchers at MIT have identified the mechanics involved in the wrinkling of thin interfacial layers within soft composite materials, and developed a model based on material properties and geometry to predict how wrinkled an internal layer may become, given its stiffness and width. The researchers also fabricated composite materials using multi-material 3-D printing, and observed the wrinkling and instability pattern — results that were correctly predicted by their model.

Narges Kaynia, a graduate student in mechanical engineering at MIT, says the model may serve as a blueprint for developing new composite materials with reversibly wrinkling interfaces. Continue reading the article on MIT News.  photo courtesy of Narges Kaynia and Yaning Li 

Most cancer deaths are caused by metastatic tumors, which break free from the original cancer site and spread throughout the body. For that to happen, cancer cells must undergo many genetic and physical changes.

Many of those genetic changes have been studied extensively, but it has been more difficult to study the physical changes. Now, MIT researchers have developed a way to study three key physical properties of cancer cells — their mass, stiffness and friction — on a large scale.

Authors from the paper include lead author and MIT postdoc Sangwon Byun, grad student Josephine Shaw, MIT postdoc Sungmin Son; Stanford University postdoc Dario Amodei; MIT grad students Nathan Cermak, Joon Ho Kang and Vivian Hecht; former MIT postdoc Monte Winslow; Tyler Jacks, the David H. Koch Professor of Biology at MIT and director of the Koch Institute; and Parag Mallick, an assistant professor of radiology at Stanford.

The rest of the article is available on MIT News.  photo courtesy of Sangwon Byun and Josephine Shaw

Always popular, the D-Lab Second Fridays showcase provides visitors with the chance to see what the creative and compassionate students are working on in the labs upstairs.  The event will take place on Friday, May 10th, 2013 from 5:00pm to 8:00pm, with free admission.  Founded by MacArthur award winner Amy Smith (who once was the Regional Beekeeping Officer for the Okavango River Delta in Botswana) the D-Lab’s mission is to improve the quality of life of low-income households through the creation and implementation of low cost technologies.  Learn more about D-Lab.

Throughout decades of research on solar cells, one formula has been considered an absolute limit to the efficiency of such devices in converting sunlight into electricity: Called the Shockley-Queisser efficiency limit, it posits that the ultimate conversion efficiency can never exceed 34 percent for a single optimized semiconductor junction.

Now, researchers at MIT have shown that there is a way to blow past that limit as easily as today’s jet fighters zoom through the sound barrier — which was also once seen as an ultimate limit.

Their work appears this week in a report in the journal Science, co-authored by graduate students including Daniel Congreve, Nicholas Thompson, Eric Hontz and Shane Yost, alumna Jiye Lee ’12, and professors Marc Baldo and Troy Van Voorhis.

Continue reading the article on MIT News.  illustration by Christine Daniloff

Osteoarthritis, which affects at least 20 percent of adults in the United States, leads to deterioration of cartilage, the rubbery tissue that prevents bones from rubbing together. By studying the molecular properties of cartilage, MIT engineers have now discovered how the earliest stages of arthritis make the tissue more susceptible to damage from physical activities such as running or jumping.  Hadi Tavakoli Nia, the lead author of the paper, and Iman Soltani Bozchalooi, both graduate students in mechanical engineering, are working to answer this question. Visit MIT News to continue reading the article.

DNA’s unique structure is ideal for carrying genetic information, but scientists have recently found ways to exploit this versatile molecule for other purposes: By controlling DNA sequences, they can manipulate the molecule to form many different nanoscale shapes.

Chemical and molecular engineers at MIT and Harvard University have now expanded this approach by using folded DNA to control the nanostructure of inorganic materials. After building DNA nanostructures of various shapes, they used the molecules as templates to create nanoscale patterns on sheets of graphene. This could be an important step toward large-scale production of electronic chips made of graphene, a one-atom-thick sheet of carbon with unique electronic properties.

Peng Yin, an assistant professor of systems biology at Harvard Medical School and a member of Harvard’s Wyss Institute for Biologically Inspired Engineering, is also a senior author of the paper, and MIT postdoc Zhong Jin is the lead author. Other authors are Harvard postdocs Wei Sun and Yonggang Ke, MIT graduate students Chih-Jen Shih and Geraldine Paulus, and MIT postdocs Qing Hua Wang and Bin Mu.

Continue reading the article on MIT News.

Using exotic particles called quantum dots as the basis for a photovoltaic cell is not a new idea, but attempts to make such devices have not yet achieved sufficiently high efficiency in converting sunlight to power. A new wrinkle added by a team of researchers at MIT — embedding the quantum dots within a forest of nanowires — promises to provide a significant boost.

Photovoltaics (PVs) based on tiny colloidal quantum dots have several potential advantages over other approaches to making solar cells: They can be manufactured in a room-temperature process, saving energy and avoiding complications associated with high-temperature processing of silicon and other PV materials. They can be made from abundant, inexpensive materials that do not require extensive purification, as silicon does. And they can be applied to a variety of inexpensive and even flexible substrate materials, such as lightweight plastics.

The team, which also included postdoc Sehoon Chang and graduate students Patrick Brown, Jayce Cheng and Paul Rekemeyer, was supported by the National Science Foundation.

Read the rest of the article on MIT News.

Remember that awful biology class where you had to memorize a million Latin names?  Did you struggle to balance chemistry equations and swear never to do that again?  MIT scientists Tyler Dewitt (G, Biology), Raoul Correa (G, Chemistry), Kate Goldstein, Sabine Hauert, Filippo Menolascina, Tal Danino, and Eben Cross will share their most memorable moments from high school science class on Wednesday, April 17th, 2013, from 6:00pm to 8:00pm at the MIT Museum.  They will also describe how those lessons continue to shape their research careers!  Tonight, allow yourself to flash back to high school, but this time with friends, acquaintances, and drink, to share those science experiences with good humor.  For a sneak peak at what to expect, check out Tyler’s TEDx talk.  Admission is free.  This event is recommended for older teens and adults.  Cash bar for ages 21+.  Check out the Facebook page.

When Jameson Toole explores the streets of Boston and Cambridge, he sees problems waiting to be solved — and he believes some solutions are already in our pockets. “Mobile phones are amazing data sensors,” says Toole, a native of Saratoga Springs, N.Y., and a second-year PhD student in the Engineering Systems Division at MIT. “Every time you use your cellphone, there is a little breadcrumb that’s stored that can be used in a lot of different ways to help improve human lives.”

Together with his adviser, Marta Gonzalez, the Gilbert W. Winslow Career Development Assistant Professor of Civil and Environmental Engineering, Toole is an advocate of big data: Specifically, he aims to harness the stockpile of information collected by our electronic devices. Whether it’s via an app or simply the data a phone company collects about its customers, Toole says, information stored in cellphones can be valuable in urban planning.

Read the rest of the article on MIT News.  photo by Allegra Boverman

Gain practice writing about your research for a broad audience by submitting an article to the Tech.  An anecdotal or informal tone is fine, and you’ll end up with a great link to send to friends and family.  Articles should be 500 to 1000 words, and will be edited by Campus Life editors before appearing in The Tech. Email emoberg@mit.edu or cl@the-tech.mit.edu for more information or to submit an article.

In an effort to bring a more human dimension to the online-education experience, Department of Electrical Engineering and Computer Science Associate Professor Rob Miller has developed a new computer system that will help provide students with feedback on their homework assignments and create more interaction between students, teachers and alumni.

Called Caesar, the system was developed by Miller, a principal investigator at the MIT Computer Science and Artificial Intelligence Lab (CSAIL), and two of his graduate students, Mason Tang and Elena Tatarchenko, to address the challenge of how to facilitate instructor feedback to the hundreds of students taking his introductory computer science course each semester. Many of the students taking the course, “Elements of Software Construction” (MIT course 6.005), are new to the subject matter, and Miller thought they would benefit from more hands-on guidance. In particular, he wanted to find a way to critique the thousands of lines of code that his students write as part of each of their homework assignments. Read the rest of the article on MIT news.

The National Science Foundation (NSF), along with the journal Science, honored a team of researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) for their video “Revealing Invisible Changes In The World,” where they used an algorithm to reveal subtle motions unseen by the naked eye. The CSAIL team — graduate students Michael Rubinstein and Neal Wadhwa, alumni Eugene Shih SM ’01, PhD ’10 and Hao-Yu Wu MNG ’12, associate professor Frédo Durand, and professors William T. Freeman and John Guttag — earned honorable mention for their video at the 10th annual International Science & Technology Visualization Challenge, a highly competitive international contest.

In the video, the researchers demonstrated an algorithm they developed that amplifies and allows for analysis of subtle movements and variations in color in ordinary videos. “Imagine you had special glasses that allowed you to see subtle changes that cannot be seen with the naked eye,” says Freeman, the video’s narrator. Continue reading the article on MIT news.

Master in City Planning (MCP) and the Special Program for Urban and Regional Studies (SPURS) students will share stories about their 2013 IAP trip in an African country during the DUSP IAP in Africa Showcase on Wednesday, March 13th, 2013 from 6:00pm to 7:30pm in MIT Room 10-401.  Panelists will include Sarah Dimson (Tanzania), Anna Gross (Ghana), Abel Managni (Ghana), and Sofia Lopez (Egypt).  The panel will be moderated by Gabriella Carolini, Assistant Professor, Department of Urban Studies and Planning.  Light dinner will be served.

Researchers at MIT, the Broad Institute and Rockefeller University have developed a new technique for precisely altering the genomes of living cells by adding or deleting genes. The researchers say the technology could offer an easy-to-use, less-expensive way to engineer organisms that produce biofuels; to design animal models to study human disease; and  to develop new therapies, among other potential applications. To create their new genome-editing technique, the researchers modified a set of bacterial proteins that normally defend against viral invaders. Using this system, scientists can alter several genome sites simultaneously and can achieve much greater control over where new genes are inserted, says Feng Zhang, an assistant professor of brain and cognitive sciences at MIT and leader of the research team.

“Anything that requires engineering of an organism to put in new genes or to modify what’s in the genome will be able to benefit from this,” says Zhang, who is a core member of the Broad Institute and MIT’s McGovern Institute for Brain Research. Zhang and his colleagues describe the new technique in the Jan. 3 online edition of Science. Lead authors of the paper are graduate students Le Cong and Ann Ran. Continue reading the article on MIT news.  photo courtesy Christine Daniloff

Almost all computer chips use two types of transistors: one called p-type, for positive, and one called n-type, for negative. Improving the performance of the chip as a whole requires parallel improvements in both types. At the IEEE’s International Electron Devices Meeting (IEDM) in December, researchers from MIT’s Microsystems Technology Laboratories (MTL) presented a p-type transistor with the highest “carrier mobility” yet measured. By that standard, the device is twice as fast as previous experimental p-type transistors and almost four times as fast as the best commercial p-type transistors.

Judy Hoyt, a professor of electrical engineering and computer science; her graduate students Winston Chern, lead author on the new paper, and James T. Teherani; Pouya Hashemi, who was an MIT postdoc at the time and is now with IBM; Dimitri Antoniadis, the Ray and Maria Stata Professor of Electrical Engineering; and colleagues at MIT and the University of British Columbia achieved their record-setting hole mobility by “straining” the germanium in their transistor — forcing its atoms closer together than they’d ordinarily find comfortable. To do that, they grew the germanium on top of several different layers of silicon and a silicon-germanium composite. The germanium atoms naturally try to line up with the atoms of the layers beneath them, which compresses them together. Read the article on MIT news.  photo courtesy of Winston Chern, Pouya Hashemi and James Teherani

Synergy is an experimental program that catalyzes partnerships between local artists and MIT graduate student research scientists. With an emphasis on communication and collaboration, Synergy aims to provide meaningful creative and intellectual experiences for both the general public and for participating artists and scientists. On March 3, 1-3pm, they will host a Panel Discussion in the Gordon Current Science & Technology Center at the Museum of Science followed by a tour of the gallery with the artists and scientists. This is a free event with exhibit hall admission; more information can be found on the Synergy Exhibit website. Sponsored by an ODGE Graduate Student Life Grant. Photo from the Synergy Exhibit Gallery.

International negotiators will come together this week in Geneva, Switzerland for the fifth and final meeting to address global controls on mercury.  Ahead of the negotiations, researchers from MIT and Harvard University are calling for aggressive emissions reductions and clear public health advice to reduce the risks of mercury.  Noelle Selin, Assistant Profressor of Engineering Systems and Atmospheric Chemistry, will be bringing along with ten MIT graduate students to present recent scientific results to negotiators in Geneva.  The students attending are Leah Stokes (Environmental Policy and Planning), Danya Rumore (Environmental Policy and Planning), Philip Wolfe (Aeronautics and Astronautics), Amanda Giang (Technology and Policy), Ellen Czaika (Engineering Systems Division), Bethanie Edwards (MIT/WHOI Joint Program in Oceanography), Mark Staples (Technology and Policy), Alice Alpert (MIT/WHOI Joint Program in Oceanography), Julie van der Hoop (MIT/WHOI Joint Program in Oceanography), and Rebecca Saari (Engineering Systems).  Read the full story here.

Smithsonian magazine recently ranked nanoporous graphene, a novel material for water desalination developed in MIT’s Department of Materials Science & Engineering, in its ranking for the top five surprising scientific milestones of 2012. Nanoporous graphene is a one-atom-thick form of carbon with tiny holes that can block salt ions while letting water molecules through, enabling the production of potable water from the world’s virtually limitless supply of seawater. The new graphene membrane was first proposed last June by MIT graduate student David Cohen-Tanugi and Jeffrey C. Grossman, Associate Professor in MIT’s Department of Materials Science and Engineering, in the journal Nano Letters. Read more about the story here.

Ad hoc networks — communication networks set up on the fly by mobile sensors — pose problems that ordinary office networks don’t. Ad hoc networks are usually decentralized, meaning that no one node knows what the network as a whole looks like. One of the questions raised by decentralized networks is how to relay messages so that they will reliably reach all the nodes, even when the network’s shape is unknown. At the ACM-SIAM Symposium on Discrete Algorithms this month, Bernhard Haeupler, a graduate student in MIT’s Department of Electrical Engineering and Computer Science, won one of two best-student-paper prizes for a new algorithm that answers that question. Continue reading here.

Phased arrays are light sources that don’t move, but can project a beam in any direction. In a recent issue of Nature, researchers from MIT’s Research Laboratory of Electronics (RLE) describe a 4,096-emitter array that fits on a single silicon chip whose wide range of potential applications include more efficient laser rangefinders; medical-imaging devices; and even holographic televisions that emit different information when seen from different viewing angles. Michael Watts, an associate professor of electrical engineering published the paper along with first author Jie Sun, a graduate student in Watts’ lab, and Sun’s fellow graduate students Erman Timurdogan, Ami Yaacobi, and RLE postdoc Ehsan Shah Hosseini. Read the full article here.

A group of MIT undergraduates, graduate students and postdocs met in January for an interdisciplinary workshop sponsored by the Department of Biology that centered on injecting design thinking into scientific research. Graduate student Greg Steinbrecher ’12 said of the workshop, “More and more, the truly inspiring and innovative research occurs at the intersection of multiple fields, and by applying the successes of one discipline to the work of another. Accordingly, science is becoming more complicated and collaborative.” Read the full story here. Photo by Charles Harper Illustration

In early 2011, a pair of theoretical computer scientists at MIT proposed an optical experiment that would harness the weird laws of quantum mechanics to perform a computation impossible on conventional computers. In December, four different groups of experimental physicists reported the completion of rudimentary versions of Aaronson and Arkhipov’s experiment within a span of three days. Justin Dove, a graduate student in the Department of Electrical Engineering and Computer Science and a member of MIT’s Optical and Quantum Communications Group is a coauthor of the paper from the University of Queensland. Read more about his research here.

Epileptic seizures occur when neurons in the brain become excessively active. However, a new study from MIT neuroscientists suggests that some seizures may originate in non-neuronal cells known as glia. This is the first time anyone has shown that mutations in glial cells can produce epileptic seizures. Counteracting the effects of the glial mutation may be a promising new strategy for developing epilepsy treatments, says Troy Littleton, an MIT professor of biology and leader of the research team. Biology Professor Troy Littleton and lead author Jan Melom, a graduate student in MIT’s Department of Biology, described their new findings in the Jan. 16 online edition of the Journal for Neuroscience. Read the full article here.

About 20 years ago, scientists discovered the gene that causes Huntington’s disease. The mutant form of the gene has many extra DNA repeats in the middle of the gene, but scientists have yet to determine how that extra length produces Huntington’s symptoms. In a new step toward answering that question, MIT biological engineers have found that the protein encoded by this mutant gene alters patterns of chemical modifications of DNA.  MIT Associate Professor of Biological Engineering Ernest Fraenkel coauthored the paper with lead author, graduate student Christopher Ng. Read the full story here.

Researchers from MIT have now found a safe and efficient way to get large molecules through the tightly regulated cell membrane, by squeezing the cells through a narrow constriction that opens up tiny, temporary holes in the membrane. Any large molecules floating outside the cell can slide through the membrane during this disruption. Robert Langer, the David H. Koch Institute Professor at MIT, is a senior author of the paper. Lead authors are chemical engineering graduate student Armon Sharei, Koch Institute research scientist Janet Zoldan, and chemical engineering research associate Andrea Adamo. Continue reading here.

When you get a cut, blood starts to flow from the wound. But very quickly, complex biochemical processes spring into action to stanch the flow. A team of MIT researchers has analyzed the process of blood clotting and found, for the first time, exactly how the different molecular components work together to block the flow of blood from a cut. Now, they are working on applying that knowledge to the development of synthetic materials that could be used to control different kinds of liquid flows, and could lead to a variety of new self-assembling materials. The research was published this week in the online journal Nature Communications, in a paper co-authored by MIT assistant professor of materials science and engineering Alfredo Alexander-Katz, graduate student Hsieh Chen, and six other researchers in the United States, Germany and Austria.

With the recent launch of MIT’s Institute for Medical Engineering and Science, MIT News examines research with the potential to reshape medicine and health care. Jenna Weins, a graduate student at CSAIL’s Data-Driven Medicine group is using machine-learning techniques to comb through dozens of variables — such as age and complaint upon admission, vital signs and lab results — to find patients that suggested elevated risk of infection with the nasty intestinal bug Clostridium difficile.

Based at the Media Lab is the New Media Medicine Group, headed by Frank Moss, professor of the practice of media arts and sciences. The group’s Collective Discovery project, which involves Moss and his graduate students John Moore and Ian Eslick, seeks to provide tools to enable members of online discussion boards to gather and organize medically relevant data about their own experiences with particular diseases and courses of treatment. Read the full article here.

MIT researchers have now come up with a new class of hydrophobic ceramics that are highly hydrophobic, but are also durable in the face of extreme temperatures and rough treatment. The work, by mechanical engineering postdoc Gisele Azimi and Associate Professor Kripa Varanasi, along with two graduate students, Hyuk-Min Kwon and Adam Paxson, and another postdoc, Rajeev Dhiman is described this week in the journal Nature Materials. Durability has always been a challenge for hydrophobic materials, Varanasi says — a challenge he says his team has now solved. Read the full story here.

Peter DeMuth of Biological Engineering and Wilfredo F. Garcia-Beltran in Health Sciences and Technology have developed new dissolving microneedles for transcutaneous delivery of biological agents such as vaccines. This work was is published in and featured on the cover of the journal Advanced Functional Materials. Congratulations to Peter and Wilfredo on this creative combination of polymer synthesis, microfabrication, confocal microscopy, in vitro and in vivo experiments, histology and whole animal fluorescence! Read the full paper here, or see a video of Peter here, as he was one of ten winners of the 2012 Koch Institute Image Awards. Photo by Advanced Functional Materials. Read more

Motivated by his personal experience with the horrors of the Sierra Leone civil war, David Moinina Sengeh is working at the MIT Media Lab to improve prosthetic limbs. In Sierra Leone many people don’t wear their prosthetic limbs because the hard plastic sockets don’t fit well. Sengeh has been working to produce custom-fitted, yet affordable, sockets. Last spring, Sengeh created a program called Innovate Salone to foster creativity among high-school students in Sierra Leone. Innovate Salone includes a mentorship program and a set of workshops where Sierra Leone’s youth can get help in developing their ideas. The idea was to “get people in the community to think about innovations that they can embrace, to have a positive impact on society [and] to get high-school kids around the country to think about a problem, and how to solve it.”  Read the full article at MIT News.

For Lindsey Anne Gilman, SM ’12, playing with bubbles is serious work. Her PhD research project, launched this past summer, concerns ways of improving heat transfer for energy production utilizing boiling water. In nuclear reactors, the formation and movement of bubbles in boiling water turns out to be a critical issue: “If instead of nice little bubbles leaving the surface of the fuel, you get a film of vapor forming, the temperature of the fuel rods can increase,” says Gilman. “When this happens, you have reached critical heat flux. The concern is that if the temperature of the fuel rods gets high enough, the structural integrity of the rods might be compromised, and even fail.”

Gilman’s studies focus on optimizing flow conditions to achieve maximum power without compromising safety. She has just begun the first phase of her project, which entails building a software model that describes precisely what is taking place inside reactors as water heats up and approaches the boiling point. Read the full article.

Anyone unfortunate enough to encounter a porcupine’s quills knows that once they go in, they are extremely difficult to remove. Researchers at MIT and Brigham and Women’s Hospital now hope to exploit the porcupine quill’s unique properties to develop new types of adhesives, needles and other medical devices.

To explore the possibility of making stronger adhesives, the researchers created a patch with an array of barbed quills on one side. They found that the energy required to remove this patch was 30 times greater than that needed for a control patch, which had quills but no barbs.

The system could also be tweaked so that it penetrates tissue easily but is not as difficult to remove as a porcupine quill, enabling design of less-painful needles for injections. “If you can still create the stress concentrations but without having a barb that catches tissue on removal, potentially you could create something with just easy insertion, without the adhesion,” says James Ankrum, a graduate student in HST, an author of the paper, and a Hugh Hampton Young fellow. Read the article on Science Daily.

Borrowing from microfabrication techniques used in the semiconductor industry, MIT and Harvard Medical School (HMS) engineers have developed a simple and inexpensive way to create three-dimensional brain tissues in a lab dish. The new technique yields tissue constructs that closely mimic the cellular composition of those in the living brain, allowing scientists to study how neurons form connections and to predict how cells from individual patients might respond to different drugs. The work also paves the way for developing bioengineered implants to replace damaged tissue for organ systems, according to the researchers.

Demirci and Ed Boyden, associate professor of biological engineering and brain and cognitive sciences at MIT’s Media Lab and McGovern Institute, are senior authors of a paper describing the new technique, which appears in the Nov. 27 online edition of the journal Advanced Materials. The paper’s lead author is Umut Gurkan, a postdoc at HST, Harvard Medical School and Brigham and Women’s Hospital. Other authors of the paper are Yantao Fan, a visiting graduate student at HMS and HST; Feng Xu and Emel Sokullu Urkac, postdocs at HMS and HST; Gunes Parlakgul, a visiting medical student at HMS and HST; MIT graduate students Jacob Bernstein (former Hugh Hampton Young fellow) and Burcu Erkmen; and Wangli Xing, a professor at Tsinghua University. Read the rest of the article in MIT Media Relations.

Providing protection against impacts from bullets and other high-speed projectiles is more than just a matter of brute strength. While traditional shields have been made of bulky materials such as steel, newer body armor made of lightweight material such as Kevlar has shown that thickness and weight are not necessary for absorbing the energy of impacts. Now, a new study by researchers at MIT and Rice University has shown that even lighter materials may be capable of doing the job just as effectively. The key is to use composites made of two or more materials whose stiffness and flexibility are structured in very specific ways — such as in alternating layers just a few nanometers thick. The research team produced miniature high-speed projectiles and measured the effects they had on the impact-absorbing material.

The results of the research are reported in the journal Nature Communications, in a paper co-authored by former postdoc Jae-Hwang Lee, now a research scientist at Rice; postdoc Markus Retsch; graduate student Jonathan Singer; Edwin Thomas, a former MIT professor who is now at Rice; graduate student David Veysset; former graduate student Gagan Saini; former postdoc Thomas Pezeril, now on the faculty at Université du Maine, in Le Mans, France; and chemistry professor Keith Nelson. The experimental work was conducted at MIT’s Institute for Soldier Nanotechnologies. Read the rest of the article on MITnews.

Within polymeric materials, there are structural flaws at the molecular level. To form an ideal network, each polymer chain would bind only to another chain. However, in any real polymeric material, a significant fraction of the chains instead bind to themselves, forming floppy loops. “If your material properties depend on having polymers connected to each other to form a network, but you have polymers folded around and connected to themselves, then those polymers are not part of the network. They weaken it,” says Jeremiah A. Johnson, an assistant professor of chemistry at MIT.

Johnson and his colleagues have now developed, for the first time, a way to measure how many loops are present in a given polymer network, an advance they believe is the first step toward creating better materials that don’t contain those weak spots. Huaxing Zhou, an MIT postdoc, is the lead author of a paper describing the new technique in this week’s issue of the Proceedings of the National Academy of Sciences. Other authors are visiting researcher Jiyeon Woo, chemistry graduate student Alexandra Cok, chemical engineering graduate student Muzhou Wang, and Bradley Olsen, an assistant professor of chemical engineering. Continue reading the article on MITnews.

A new study from MIT and Massachusetts General Hospital (MGH) reveals, for the first time, what happens inside the brain as patients lose consciousness during anesthesia. By monitoring brain activity as patients were given a common anesthetic, the researchers were able to identify a distinctive brain activity pattern that marked the loss of consciousness. This pattern, characterized by very slow oscillation, corresponds to a breakdown of communication between different brain regions, each of which experiences short bursts of activity interrupted by longer silences.

“Within a small area, things can look pretty normal, but because of this periodic silencing, everything gets interrupted every few hundred milliseconds, and that prevents any communication,” says Laura Lewis, a graduate student in MIT’s Department of Brain and Cognitive Sciences (BCS) and one of the lead authors of a paper describing the findings in the Proceedings of the National Academy of Sciences this week. This pattern may help anesthesiologists to better monitor patients as they receive anesthesia, preventing rare cases where patients awaken during surgery or stop breathing after excessive doses of anesthesia drugs. Continue reading the article on MITnews.

In the last 10 years, it’s become far more common for physicians to keep records electronically. Those records could contain a wealth of medically useful data: hidden correlations between symptoms, treatments and outcomes, for instance, or indications that patients are promising candidates for trials of new drugs. Much of that data, however, is buried in physicians’ freeform notes. One of the difficulties in extracting data from unstructured text is what computer scientists call word-sense disambiguation. In a physician’s notes, the word “discharge,” for instance, could refer to a bodily secretion — but it could also refer to release from a hospital. The ability to infer words’ intended meanings makes it much easier for computers to find useful patterns in mountains of data.

Graduate student Rachel Chasin is a co-authour of the paper concerning algorithmically distinguishing words with multiple possible meanings in medical records; postdoc Anna Rumshisky led the research with Peter Szolovits, MIT professor of computer science and engineering and health science and technology, and Özlem Uzuner, a research affiliate.  Continue reading the article on MITnews.

In the event that a giant asteroid is headed toward Earth, you’d better hope that it’s blindingly white. A pale asteroid would reflect sunlight — and over time, this bouncing of photons off its surface could create enough of a force to push the asteroid off its course. How might one encourage such a deflection? The answer, according to an MIT graduate student: with a volley or two of space-launched paintballs.

Sung Wook Paek, a graduate student in MIT’s Department of Aeronautics and Astronautics, says if timed just right, pellets full of paint powder, launched in two rounds from a spacecraft at relatively close distance, would cover the front and back of an asteroid, more than doubling its reflectivity, or albedo. The initial force from the pellets would bump an asteroid off course; over time, the sun’s photons would deflect the asteroid even more. Read the rest of the article on MITnews.

The glowing green molecule known as green fluorescent protein (GFP) has revolutionized molecular biology. When GFP is attached to a particular protein inside a cell, scientists can easily identify and locate it using fluorescence microscopy. However, GFP can’t be used with electron microscopy, which offers much higher resolution than fluorescence microscopy. Chemists from MIT have now designed a GFP equivalent for electron microscopy — a tag that allows scientists to label and visualize proteins with unprecedented clarity.

“With things that may appear only a few pixels across by fluorescence microscopy — for example, a mitochondrion — you can’t make out any of the internal features. But with electron microscopy it’s very easy to discern the intricate internal structures,” says Jeff Martell, a graduate student in chemistry at MIT and lead author of a paper describing the new tag in the Oct. 21 online edition of Nature Biotechnology. The new tag could help scientists pinpoint the locations of many cell proteins, providing new insight into those proteins’ functions, according to the researchers. To read the rest of the article, visit MITnews.

Condensers are a crucial part of today’s power generation systems: About 80 percent of all the world’s powerplants use them to turn steam back to water after it comes out of the turbines that turn generators. They are also a key element in desalination plants, a fast-growing contributor to the world’s supply of fresh water. Now, a new surface architecture designed by researchers at MIT holds the promise of significantly boosting the performance of such condensers. The research is described in a paper just published online in the journal ACS Nano by MIT postdoc Sushant Anand; Kripa Varanasi, the Doherty Associate Professor of Ocean Utilization; and graduate student Adam Paxson, postdoc Rajeev Dhiman and research affiliate Dave Smith, all of Varanasi’s research group at MIT.

The key to the improved hydrophobic (water-shedding) surface is a combination of microscopic patterning — a surface covered with tiny bumps or posts just 10 micrometers (millionths of a meter) across, about the size of a red blood cell — and a coating of a lubricant, such as oil. The tiny spaces between the posts hold the oil in place through capillary action, the researchers found. Continue reading the article on MITnews.

In many respects, metamaterials are supernatural. These manmade materials, with their intricately designed structures, bend electromagnetic waves in ways that are impossible for materials found in nature. Scientists are investigating metamaterials for their potential to engineer invisibility cloaks — materials that refract light to hide an object in plain sight — and “super lenses,” which focus light beyond the range of optical microscopes to image objects at nanoscale detail. Researchers at MIT have now fabricated a three-dimensional, lightweight metamaterial lens that focuses radio waves with extreme precision. The concave lens exhibits a property called negative refraction, bending electromagnetic waves — in this case, radio waves — in exactly the opposite sense from which a normal concave lens would work.

For Isaac Ehrenberg, an MIT graduate student in mechanical engineering, the device evokes an image from the movie “Star Wars”: the Death Star, a space station that shoots laser beams from a concave dish, the lasers converging to a point to destroy nearby planets. While the researchers’ fabricated lens won’t be blasting any planetary bodies in the near future, Ehrenberg says there are other potential applications for the device, such as molecular and deep-space imaging. To continue reading the article, visit MITnews.

In computer science, the buzzword of the day is “big data.” The proliferation of cheap, Internet-connected sensors — such as the GPS receivers, accelerometers and cameras in smartphones — has meant an explosion of information whose potential uses have barely begun to be explored. In large part, that’s because processing all that data can be prohibitively time-consuming.

Most computer scientists try to make better sense of big data by developing ever-more-efficient algorithms. But in a paper presented this month at the Association for Computing Machinery’s International Conference on Advances in Geographic Information Systems, MIT researchers take the opposite approach, describing a novel way to represent data so that it takes up much less space in memory but can still be processed in conventional ways. While promising significant computational speedups, the approach could be more generally applicable than other big-data techniques, since it can work with existing algorithms.

EECS graduate student Cynthia Sung is the paper’s third author, along with postdoc Dan Feldman and Daniela Rus, the director of MIT’s Computer Science and Artificial Intelligence Laboratory.  Read the rest of the article on MITnews.

Many species exhibit cooperative survival strategies — for example, sharing food or alerting other individuals when a predator is nearby. However, there are almost always freeloaders in the population who will take advantage of cooperators. This can be seen even among microbes such as yeast, where “cheaters” consume food produced by their neighbors without contributing any of their own. In light of this, evolutionary biologists have long wondered why cooperation remains a viable survival strategy, since there will always be others who cheat. Now, MIT physicists have found a possible answer to this question: Among yeast, cooperative members of the population actually have a better chance of survival than cheaters when a competing species is introduced into an environment. Hasan Celiker, an MIT graduate student in electrical engineering and computer science, is the paper’s lead author.  Continue reading the article on MITnews.

The MIT Summer Research Program (MSRP) provides nine exciting weeks of intensive research experience to undergraduates considering graduate school. This past summer, 39 interns conducted research in 14 different departments, working in labs under the guidance of experienced scientists and engineers who are MIT faculty members, postdoctoral fellows, and advanced graduate students. Nineteen of the host labs were new to the program, joining over 250 faculty members who have been key to MSRP’s success since it began. MSRP seeks to promote the value of graduate education; to improve the research enterprise through increased diversity; and to prepare and recruit the best and brightest for graduate education at MIT. Students who participate in this program will be better prepared and motivated to pursue advanced degrees, thereby helping to sustain a rich talent pool in critical areas of research and innovation. Click “Read more” to see a great video about this past summer, or visit the MSRP page on the ODGE website.

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If you throw a ball underwater, you’ll find that the smaller it is, the faster it moves: A larger cross-section greatly increases the water’s resistance. Now, a team of MIT researchers has figured out a way to use this basic principle, on a microscopic scale, to carry out biomedical tests that could eventually lead to fast, compact and versatile medical-testing devices. The results, based on work by graduate student Elizabeth Rapoport and assistant professor Geoffrey Beach, of MIT’s Department of Materials Science and Engineering (DMSE), are described in a paper published in the journal Lab on a Chip. MIT graduate student Daniel Montana ’11 also contributed to the research as an undergraduate. Continue reading this article on MIT news or click “More” to see the video. Read more