Brown Engineering Alumnus Michael Escuti wins Presidential Award for Young Scientists and Engineers

Dr. Michael Escuti ScM '99 PhD '03, who received both his master's degree and Ph.D. in electrical engineering from Brown University and is now a North Carolina State University engineering professor has won the U.S. government's top award for early-career scientists and engineers.

Escuti, associate professor of electrical and computer engineering at NC State, will receive the Presidential Early Career Award for Scientists and Engineers later this fall, the White House announced. The awards program, established by President Bill Clinton in 1996, honors researchers for working at the frontiers of science and technology and serving the community through scientific leadership, public education or outreach.

Winners receive research grants of up to five years to support their work.

Escuti was honored for his pioneering development of liquid crystal "polarization gratings," which consist of a thin layer of liquid crystal material on a glass plate. The White House also recognized him for educating students through collaborations with international academic teams and industries, as well as for outreach work in underserved communities.

Escuti's research has shown how polarization gratings, as well as devices and applications based on them, can solve problems in optics that had been previously thought unsolvable. One result of the work is a very energy-efficient way of steering laser beams that is precise and relatively inexpensive. The research has potential applications in laser radar and free space communication, which uses lasers to transfer data between platforms – such as between satellites or between aircraft and soldiers on the battlefield. Escuti's team, consisting of NC State students along with partner Boulder Nonlinear Systems Inc., has already delivered prototypes of the technology to the U.S. Air Force and is working on other applications.

Another result is a low-loss light switch, which inherently acts on all components of light rather than just the correctly polarized half, meaning that it is very transparent when it is open and very dark when closed. Other results include high-resolution spectral/polarization cameras, which enable compact and low-cost imaging beyond what our eyes can see for platforms such as aerial vehicles, satellites and biomedical imaging.

Escuti is commercializing his research through several industrial partnerships, including his own start-up company, ImagineOptix Corp., that has already prototyped a tiny, highly efficient projection display that could revolutionize displays on hand-held and mobile devices.

His work has resulted in a National Science Foundation (NSF) CAREER Award, three awarded patents and nine pending patents. He has also received $4.3 million in external research funding from NSF, and many other federal, state, and private sources.

After receiving his Ph.D. in electrical engineering from Brown University in 2003, Escuti joined the NC State faculty in 2004.

Portions of this release courtesy of North Carolina State University.

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Nanoskin Saves Lives and Limbs

Engineers and Orthopedics Experts Reduce Risk of Infection from Medical Prostheses with Nanotech that Mimics Human Skin

Engineers and orthopedics experts are applying nanotechnology to prosthetic medical devices in order to increase patient safety. By closely mimicking human skin, experts hope to reduce the infection-inducing bacteria that grow on prostheses. Changing the texture of the devices in small ways results in a big reduction in bacteria growth, as well as improvement of skin closures and bone growth.

Nanoskin saves lives and limbs - San Diego, California News Station - KFMB Channel 8 - cbs8.com

Losing a limb can be devastating and in the United States there are approximately 1.7 million people living that way. One of the biggest fears for those who use prosthetic devices is getting an infection. But researchers are working on a way to mimic the human skin to cut down on infections.

“I went to bed and woke up the next morning and my body was swollen and I had blisters all over it,” Anthony Buttaro, a man who suffered limb loss, told Ivanhoe.

That morning Anthony Buttaro rushed to the hospital. Doctors diagnosed him with MRSA the often deadly infection forced doctors to amputate his left arm. Now Anthony uses a prosthetic device but he is still concerned about infections.
“I’m always worried about it,” Buttaro said.

To ease those fears engineers and experts in orthopedics at Brown University are applying nanotechnology to medicine called nanomedicine to mimic the tiniest features and contours of human skin.

“Skin serves as a barrier to keep bacteria out of the body,” Thomas Webster an engineer at Brown University told Ivanhoe.

Screws are often used to attach the prosthetic device to bone, but bacteria can grow on the screws causing an infection.
“We are talking really, really small features that are making a difference,” Webster said.

The difference comes by changing the texture of the screw. First it is dipped into hydrofluoric acid. At the same time voltage is applied to create the tissue like features.

“What we are seeing, we’re reducing bacteria growth, on these implants, we’re improving skin closures around the implants and improving bone growth,” Webster explained.

By mimicking the skin researchers believe it will cut down on infections, saving lives and limbs. The nanoskin technology is still in the study phase, but researchers hope to start human testing in the future.


ABOUT NANOTECHNOLOGY: Nanotechnology is science at the size of individual atoms and molecules -- objects and devices measuring mere billionths of a meter, smaller than a red blood cell. At this size scale, materials have different chemical and physical properties than the same materials in bulk, because quantum mechanics is more important. For example, carbon atoms can conduct electricity and are stronger than steel when woven into hollow microscopic threads. Nanoparticles are already widely used in certain commercial consumer products, such as suntan lotions, "age-defying" make-up, and self-cleaning windows that shed dirt when it rains. One company manufactures a nanocrystal wound dressing with built-in antibiotic and anti-inflammatory properties. On the horizon is toothpaste that coats, protects and repairs damaged enamel, as well as self-cleaning shoes that never need polishing. Nanoparticles are also used as additives in building materials to strengthen the walls of any given structure, and to create tough, durable, yet lightweight fabrics.


The Biophysical Society and the Materials Research Society contributed to the information contained in the TV portion of this report.

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Brown University School of Engineering professor Vivek Shenoy's work on thermal transport across grain boundaries in graphene (published in Nano Letters last month) has also been featured in the research highlights section of Nature Materials. An abstract of his paper, "Thermal transport across Twin Grain Boundaries in Polycrystalline Graphene from Nonequilibrium Molecular Dynamics Simulations" follows:

Heat at the borders

Fabio Pulizzi

Nature Materials

 

10,

 

724

 

(2011)

Published online

 

23 September 2011

Nano Letters http://dx.doi.org/10.1021/nl202118d (2011)

Graphene exhibits the highest thermal conductivity ever observed. Its thermal transport has been studied theoretically and experimentally, mostly in single-crystalline graphene. Unfortunately, large-scale growth, for example by chemical vapour deposition (CVD), usually yields polycrystalline sheets. Akbar Bagri and colleagues have performed molecular dynamic simulations of the thermal transport across various grain boundary orientations in graphene. They assumed a constant heat flow through the material, calculated the temperature profile and from that estimated the thermal conductivity. Interestingly, they found abrupt jumps in the temperature at the grain boundaries, which depend on the boundary orientation and grain size. The estimated grain boundary thermal conductivity is much higher than in the case of other materials with high thermal conductivity, such as nanocrystalline diamond. The results are particularly important in view of potential applications based on CVD-grown graphene. It will be interesting to see how the experiments will compare with these predictions.


For the full html version from NanoLetters, please go to:
http://pubs.acs.org/doi/full/10.1021/nl202118d

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Brain researchers study high-tech ways to overcome injury

About a year after winning a major share of a nearly $15-million grant, a team of Brown professors is developing and using new technologies to study the brain. Their goal is to inform the development of therapies that could restore functions lost to injury and stroke.

PROVIDENCE, R.I. [Brown University] — When six engineering and neuroscience professors took on Brown’s major role in the $14.9-million REPAIR project a little more than a year ago, they also took on a dream. Their goal is to understand the workings of the brain’s circuitry so well that it would be possible to fix a traumatic brain injury.

“The ability to help people who are severely disabled or injured in ways that no current medical treatment can cure is the dream,” said Arto Nurmikko, professor of engineering, who is the co-primary investigator of the project. It’s funded by the Defense Advanced Research Projects Agency, and is shared with Stanford University, the University of California–San Francisco and University College London.


New research to REPAIR the brain

The Brown team, which includes neuroscientists Rebecca Burwell, Barry Connors, John Donoghue, David Sheinberg, and Leigh Hochberg, hopes to ferret out how circuits of brain cells work to perceive the environment, process a physical response to it, and then command the body to act out that plan. For people who’ve suffered brain damage, the scientists’ goal will be to translate knowledge into treatments that can restore impaired functions.

“If there is an injury that leads to some kind of dysfunction in the brain, do we understand enough so as to substitute the missing part or the broken part with some of the kinds of the control technology we are trying to develop and replace that function?” Sheinberg said. “Do we understand how the visual system works well enough so that in the absence of a particular part of the visual system we can deliver signals artificially that might serve as a viable substitute?”

The goal is bold but the team is encouraged by the advent of a new technology called optogenetics. It allows them to genetically engineer brain cell circuits to be controlled with pulses of light. Blue light makes the cells active. Yellow light makes them inactive. The technology, developed by project collaborator Karl Deisseroth at Stanford, therefore allows scientists to control functions within the brain in the millisecond timescale of its natural operation. That technology, coupled with the traditional technique of reading out brain signals electrically, gives the researchers the ability to selectively change how brain cells are working and at the same time observe the response of connected cells.

“The optogenetic methodology is fairly new and it’s promising to revolutionize the experimental tools that we have for exploring how the brain processes information and remaps and reorganizes,” Burwell said. “This will be one way that we can target an individual neuron in order to change its patterns of activity. This would be the way that we write in a signal.”

To make such a read-write interface with the brain feasible, Nurmikko and his lab’s members in the first year have invented a new device they call the “optrode.” The prototype device delivers laser pulses to the brain to control circuits and records the electrical activity of neurons all within a wire comparable in width to a hair.

In experiments with rodents, Connors uses optogenetics to discern how individual cell behavior influences the operation of brain circuits, and Burwell is using optogenetics to study how brain circuits underlying functions such as attention and memory guide decision making and behavior. Sheinberg uses these methods to study visual perception and recognition, and Donoghue and Hochberg study how the brain produces physical movement commands. All together, the work will produce needed new findings in perception, cognition, and movement that can inform new therapies for people who have lost any of those functions to injury.

“There’s an awful lot to be learned,” Nurmikko said. “This paradigm of listening to the brain while actually informing the brain [with] methods that have not been available before, will elevate that understanding to a completely new level.”

By David Orenstein

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Why carbon nanotubes spell trouble for cells

Carbon nanotubes and other long nanomaterials can spell trouble for cells. The reason: Cells mistake them for spheres and try to engulf them. Once they start, cells cannot reverse course, and complete ingestion never occurs. Researchers at Brown University detail for the first time how cells interact with carbon nanotubes, gold nanowires and asbestos fibers. Results are published in Nature Nanotechnology.

PROVIDENCE, R.I. [Brown University] — It’s been long known that asbestos spells trouble for human cells. Scientists have seen cells stabbed with spiky, long asbestos fibers, and the image is gory: Part of the fiber is protruding from the cell, like a quivering arrow that’s found its mark.

Something perpendicular this way comesCells ingest things by engulfing them. When a long
perpendicular fiber comes near, the cell senses
only its tip, mistakes it for a sphere, and begins
engulfing something too long to handle. Credit: Gao Lab/Brown University

But scientists had been unable to understand why cells would be interested in asbestos fibers and other materials at the nanoscale that are too long to be fully ingested. Now a group of researchers at Brown University explains what happens. Through molecular simulations and experiments, the team reports in Nature Nanotechnology that certain nanomaterials, such as carbon nanotubes, enter cells tip-first and almost always at a 90-degree angle. The orientation ends up fooling the cell; by taking in the rounded tip first, the cell mistakes the particle for a sphere, rather than a long cylinder. By the time the cell realizes the material is too long to be fully ingested, it’s too late.

“It’s as if we would eat a lollipop that’s longer than us,” said Huajian Gao, professor of engineering at Brown and the paper’s corresponding author. “It would get stuck.”

The research is important because nanomaterials like carbon nanotubes have promise in medicine, such as acting as vehicles to transport drugs to specific cells or to specific locations in the human body. If scientists can fully understand how nanomaterials interact with cells, then they can conceivably design products that help cells rather than harm them.

“If we can fully understand (nanomaterial-cell dynamics), we can make other tubes that can control how cells interact with nanomaterials and not be toxic,” Gao said. “We ultimately want to stop the attraction between the nanotip and the cell.”

---

Misrecognition
Receptors on the cell’s surface crowd around the nanotube, effectively standing it upright. The cell mistakes the tube for a sphere and begins to engulf it.
 Credit: Gao Lab/Brown University

---

Like asbestos fibers, commercially available carbon nanotubes and gold nanowires have rounded tips that often range from 10 to 100 nanometers in diameter. Size is important here; the diameter fits well within the cell’s parameters for what it can handle. Brushing up against the nanotube, special proteins called receptors on the cell spring into action, clustering and bending the membrane wall to wrap the cell around the nanotube tip in a sequence that the authors call “tip recognition.” As this occurs, the nanotube is tipped to a 90-degree angle, which reduces the amount of energy needed for the cell to engulf the particle.

Once the engulfing — endocytosis — begins, there is no turning back. Within minutes, the cell senses it can’t fully engulf the nanostructure and essentially dials 911. “At this stage, it’s too late,” Gao said. “It’s in trouble and calls for help, triggering an immune response that can cause repeated inflammation.”

The team hypothesized the interaction using coarse-grained molecular dynamic simulations and capped multiwalled carbon nanotubes. In experiments involving nanotubes and gold nanowires and mouse liver cells and human mesothelial cells, the nanomaterials entered the cells tip-first and at a 90-degree angle about 90 percent of the time, the researchers report.

“We thought the tube was going to lie on the cell membrane to obtain more binding sites. However, our simulations revealed the tube steadily rotating to a high-entry degree, with its tip being fully wrapped,” said Xinghua Shi, first author on the paper who earned his doctorate at Brown and is at the Chinese Academy of Sciences in Beijing. “It is counter-intuitive and is mainly due to the bending energy release as the membrane is wrapping the tube.”

The team would like to study whether nanotubes without rounded tips — or less rigid nanomaterials such as nanoribbons — pose the same dilemma for cells.

“Interestingly, if the rounded tip of a carbon nanotube is cut off (meaning the tube is open and hollow), the tube lies on the cell membrane, instead of entering the cell at a high-degree-angle," Shi said.

Agnes Kane, professor of pathology and laboratory medicine at Brown, is a corresponding author on the paper. Other authors include Annette von dem Bussche from the Department of Pathology and Laboratory Medicine at Brown and Robert Hurt from the Institute for Molecular and Nanoscale Innovation at Brown.

The National Science Foundation, the U.S. Department of Commerce National Institute of Standards and Technology, the National Institute of Environmental Health Sciences Superfund Research Program, and the American Recovery and Reinvestment Act funded the research.

By Richard Lewis

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Dean Larry Larson featured in Providence Business News

New Brown School of Engineering Dean Larry Larson is profiled by the Providence Business News.

Five Questions With: Larry Larson

By Kimberley Donoghue 
PBN Web Editor
Twitter: @ kdonog

COURTESY BROWN UNIVERSITY          "A GREAT UNIVERSITY thrives on the quality of its faculty, and the best faculty member is a rare combination of a brilliant and ambitious researcher and an engaged and passionate teacher," said Larry Larson, The new dean of Brown University’s School of Engineering.

Lawrence Larson became the inaugural dean of Brown University’s School of Engineering, which was approved to be elevated from a division to a school last year.

Larson, an expert in microelectronics technology and wireless communications, came to Providence from his role as the chair of the Electrical and Computer Engineering Department in the Jacobs School of Engineering at the University of California-San Diego.Last year, Larson predicted that within a decade wireless devices and sensors will be so inexpensive that they could be embedded into almost any manufactured object and located anywhere thought GPS technology in his presentation “Wireless Everywhere and in Everything.”

PBN: First of all, congratulations on your new role. How do you see your first year going? Do you feel ready for the position? Is this a big leap from your previous roles?

LARSON: Thank you! It is great to be here in Providence – after 30 years in southern California, my family and I are looking forward to the beautiful New England fall.

I’m planning to spend a lot of my first year working with everyone at Brown to build momentum for the growth of the School of Engineering. We’re trying to build a world-class research enterprise in Engineering, which builds on our historic strengths in teaching and research, and on our wonderful students.

Becoming a dean is a huge leap for anyone – there are no “dean schools” – but I’m fortunate to have a wonderful staff and amazing faculty here at Brown to help me. So far, the transition has been just great.

PBN: You’ve said that your primary goal is to recruit new faculty in cutting-edge research areas. Who’s on your dream list?

LARSON: A great university thrives on the quality of its faculty, and the best faculty member is a rare combination of a brilliant and ambitious researcher and an engaged and passionate teacher. My major goal for the next few years will be to find these special people and convince them that Brown is the place they should spend the rest of their careers. We’ll be recruiting in areas of Engineering that have special interdisciplinary connections to the rest of Brown, and are in emerging areas of key societal needs: health care, the environment, energy and entrepreneurship.

PBN: You’ve also mentioned that you’d like to expand on graduate programs and create “groundbreaking” undergraduate programs. What did you have in mind?

LARSON: Most engineers go on to do graduate work at some point in their careers – it’s almost a requirement if you want to do cutting-edge work. One of our goals in the coming years is to expand our offerings of master’s degree programs that are targeted at students who want to take this next step in their careers. At the same time we also intend to expand our Ph.D.-level research, which is a key means for creating the new knowledge and new technologies that create new jobs and benefits all of society.

Life-changing undergraduate education is the heart of Brown University. One of the things I want to expand in the coming years is undergraduate research opportunities. Brown’s undergraduates are just amazing, and I want to make sure that each of them has the opportunity to work in a professor’s lab and have a meaningful research experience.

PBN: How do you plan to lead Brown’s school through the “fundamental transformation” that engineering is undergoing as barriers between traditional disciplines meld? What’s the strategy?

LARSON: One of the reasons I was attracted to Brown is its unique collaborative and interdisciplinary culture. This culture is uniquely well suited to the changes that are going on in the world around us, where traditional barriers between disciplines are breaking down, and great new opportunities lie at the boundaries between disciplines. So, we will look for new faculty members who are well suited to thrive in this new world in which we find ourselves. We already have some great examples of faculty here in Engineering who are leading the way. For example, Professor Arto Nurmikko’s work with John Donoghue and the Warren Alpert Medical School on brain interface technologies unites the disciplines of neuroscience, engineering, biology and medicine.

PBN: Where’s the current weak spot at the school that you’d like to fix?

LARSON: I’ve been amazed by the broad strengths of the Brown program since I arrived. The engineering program at Brown is the oldest in the Ivy League and the third oldest civilian engineering program in the U.S. So, we have a rich and distinguished history. We’re really focused on making it even better and more visible, by recruiting the best faculty, expanding our educational offerings, and building a modern and expanded space for our ground-breaking research.

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Bioengineering Professor Leads Research on Head Impacts and Concussions in Football

Researchers, including biomedical engineering Professor Joseph J. "Trey" Crisco,  gathered data on the frequency, direction, and magnitude of head impacts from players who wore sensor-equipped helmets during three football seasons at Brown University, Dartmouth College, and Virginia Tech. The data amount to a measure of players’ exposure to head impacts, which can ultimately help physicians and scientists understand how concussions occur.


PROVIDENCE, R.I. — Thousands of college football players began competing around the nation this week, but with the thrill of the new season comes new data on the risks of taking the field. A new study reports that running backs and quarterbacks suffer the hardest hits to the head, while linemen and linebackers are hit on the head most often. The researchers measured head blows during games and practices over three seasons at Brown University, Dartmouth College, and Virginia Tech.

The study, led by Joseph J. Crisco, professor of orthopaedics in the Warren Alpert Medical School of Brown University and director of the bioengineering laboratory at Rhode Island Hospital, documented 286,636 head blows among 314 players in the 2007-09 seasons. Crisco said the new data on the magnitude, frequency, and location of head blows amounts to a measure of each player’s head impact exposure. Ultimately it can help doctors understand the biomechanics of how blows to the head result in injury.

“This allows us to quantify what the exposure is,” Crisco said. “It is the exposure that we need to build upon, so that we can then start understanding what the relationships are with acute and chronic head injury.”

The study appears online in advance in the Journal of Biomechanics.

Concussions and other head injuries have become a source of elevated concern in football and other sports in recent years, with various leagues revising policies to protect players better. In part based on seeing this new data, said Robin Harris, Ivy League executive director, league officials announced earlier this year that full-contact practices would be limited to two a week.

Hits by position

The new study documents the nature of head blows by player position. Players on the three teams wore helmets equipped with wireless sensors that measured acceleration in various directions. That data allowed the team of researchers from Brown, Dartmouth, Virginia Tech, and sensor-maker Simbex to discern how hard the hit was, how often each player was hit, and where on the helmet they were hit.

Crisco devised the algorithm that Simbex’s Head Impact Telemetry System uses to measure head impacts. The system’s development and this study were funded by the National Institute of Child Health and Human Development and the National Operating Committee on Standards for Athletic Equipment.

The data on head acceleration and hit direction are used to calculate a composite score of exposure called HITsp that researchers believe might be a good predictor of concussion. On average, running backs had the highest HITsp, 36.1, followed by quarterbacks with 34.5 and linebackers at 32.6. Offensive and defensive linemen had the lowest HITsp numbers, with 29.0 and 28.9 respectively, but along with linebackers, they were hit on the head most often. Doctors worry not only about hit severity, but also hit frequency, because repeated head impacts may cause “subconcussive” neurological damage over time.

By analyzing head impacts by position, Crisco said, researchers can help football league officials and equipment designers begin to think about ways to make players safer.

“It will allow us to begin to understand how to control the exposures,” Crisco said. Controlling head impact exposure is critical, he added, because there are currently no treatments for acute or chronic brain injuries, and helmets cannot prevent injuries for all players in all situations.

One possibility could include rule changes. Another could include designing helmets for specific positions.

Crisco and his colleagues are now analyzing data about concussions during the three seasons to determine how and whether head impact exposure is associated with injury. He recently co-authored another paper about male and female collegiate hockey players, which reported that although women were diagnosed with more concussions, they sustained fewer and less severe head impacts.

Although Crisco’s analysis is still underway, his insights into head impact exposure led him and co-author Richard Greenwald, a Dartmouth engineer, to write a commentary earlier this year in Current Sports Medicine Reports, in which they argued that intentional use of the head in sports must be curbed.

“We propose the adoption of rules — or in some sports, we champion the enforcement of existing rules — that eliminate intentional head contact in helmeted sports,” they wrote. “When coupled with education that leads to modified tackling, blocking, or checking techniques, these rules will reduce head impact exposure and have the potential to reduce the incidence and severity of brain injury.”

Crisco, a former college football and lacrosse player, said he is passionate about contact sports and believes they have many benefits.

“Hitting is an essential component,” he said. “But intentional hitting with your head was never part of any sport and is poor technique.”

In addition to Crisco and Greenwald, other authors of the paper are Bethany Wilcox of Brown; Jonathan Beckwith and Jeffrey Chu of Simbex; Stefan Duma and Steve Rowson of Virginia Tech and Wake Forest; and Ann-Christine Duhaime, Arthur Maerlender, and Thomas McAllister of Dartmouth.

By David Orenstein

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