Twenty-three Students Inducted into Tau Beta Pi

Tau Beta Pi, the engineering honor society, inducted 23 new members into the Rhode Island Alpha chapter at Brown University on Saturday, December 4. Fourteen juniors were inducted along with eight seniors and one graduate student.

Among the 14 juniors elected were: James Arthur Bensson ’12, Brian John Bierig ’12, Michael Caron ’12, Mark Andrew Guttag ’12, Warren Bruce Jin ’12, Yosuke Korokawa ’12, Francis Liu ’12, Alec Roelke ’12, Wichinpong Sinchaisri ’12, Dingyi Sun ’12, Kathryn Ries Tringale ’12, Lingke Wang ’12, and Brent Zajaczkowski ’12.

The eight seniors elected included: Jake Lipton Albert ’11, Brendan James Checkett ’11, Kevin Thomas Durfee ’11, Martin Fagan Finn ’11, Margaret Helen Henderson Merritt ’11, Christopher Casey Moynihan ’11, Nikolas Jurjans Osvalds ’11, Daniel P. Prendergast ’11, and Theresa Marie Raimondo ’11.

Gregory James Rizza Ph.D.’12 was the graduate student elected.
 
Tau Beta Pi, founded in 1885, is the second oldest Greek-letter honor society in America; the oldest is Phi Beta Kappa. While Phi Beta Kappa is restricted to students in the liberal arts, Tau Beta Pi is designed to “offer appropriate recognition for superior scholarship and exemplary character to students in engineering.” In order to be inducted into the prestigious honor society, juniors must rank in the top eighth of their class and seniors must rank in the top fifth of their class. Graduate students who have completed at least 50% of their degree requirements and who rank in the top fifth of their class are also eligible to become candidates for membership.
 
The Rhode Island Alpha chapter is not only an honor society to pay tribute to outstanding students, it also provides a vehicle for these students to assume a role of leadership at Brown and to be of distinctive service. Tau Beta Pi members are active in engineering student publications, the engineering recruiting project, and in a variety of other organizations. 

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Malaria-infected cells stiffen, block blood flow

A team of researchers at Brown University and the Massachusetts Institute of Technology has completed the first modeling, followed by experiments, of how red blood cells are infected by a malarial parasite that attacks the brain. The researchers report that infected cells stiffen by as much as 50 times more than healthy cells. Infected cells also tend to stick along blood vessel walls, impeding the flow of blood to critical organs. Results appear in the early online edition of the Proceedings of the National Academy of Sciences.

Less elastic, more viscousThe malaria parasite inside a red blood cell, left, and
 in a computer-generated model. Malarial infection
 inhibits the smooth flow of blood through capillaries.

PROVIDENCE, R.I. [Brown University] — Although the incidence of malaria has declined in all but a few countries worldwide, according to a World Health Organization report earlier this month, malaria remains a global threat. Nearly 800,000 people succumbed to the mosquito-borne disease in 2009, nearly all of them in the developing world.

Physicians do not have reliable treatment for the virus at various stages, largely because no one has been able to document the malaria parasite’s journeys in the body.

Now researchers at Brown University and the Massachusetts Institute of Technology have used advanced computer modeling and laboratory experiments to show how malaria parasites change red blood cells and how the infected cells impede blood flow to the brain and other critical organs.

Their findings, published in the early online edition of the Proceedings of the National Academy of Sciences, could help doctors chart, in real time, the buildup in the body of cells infected with malaria or other diseases (such as sickle-cell anemia) and to prescribe treatment accordingly.

“The idea is to predict the evolution of these diseases, just like we predict the weather,” said George Karniadakis, professor of applied mathematics at Brown and corresponding author on the paper.

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Impeding forward progress
Malaria-infected red blood cells can be 50 times stiffer and have surface changes that disrupt the smooth flow of blood, depriving the brain and other organs of nutrients and oxygen. (Computer simulation by the Karniadakis Lab)

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The researchers worked withPlasmodium falciparum, a parasite that can cause cerebral malaria by lodging in capillaries of the brain, especially among children. The parasite is found globally but is most common in Africa.

Once introduced into the human body by an infected mosquito’s bite, the parasite invades red blood cells. Healthy red blood cells are tremendously elastic; even though they can reach 8 microns in length and 2 microns in thickness, they can easily slide through a capillary just 3 microns in diameter. Capillaries are vital conduits in the human brain and other organs; red blood cells are key transporters of oxygen and nutrients.

Through extensive modeling carried out on one of the world’s fastest supercomputers at the National Institute for Computational Sciences, Karniadakis and colleagues found that malaria-infected red blood cells stiffened as much as 50 times more than healthy red blood cells. The result: Infected red blood cells, having lost their elasticity, could no longer pass through capillaries, effectively blocking them.

“Basically what happens is the brain could be deprived of nutrients and oxygen,” said Karniadakis, a member of the Center for Fluid Dynamics, Turbulence and Computation at Brown. “This happens because of the deformation of these red blood cells.

“This shows that as stiffening increases (in red blood cells), the viscosity of the blood increases, and the heart has to pump twice as much sometimes to get the same blood flow,” Karniadakis added.

The researchers also found that infected red blood cells had a tendency to stick, flip, and flop along the walls of blood vessels — unlike healthy blood cells that flow in the middle of the channel. For reasons not entirely known, the infected red blood cells develop little knobby protrusions on their cellular skin that tend to stick to the surface of the blood wall, known as the endothelium. Scientists call the sticking cytoadhesion.

“So, what happens is the infected red blood cell is not only stiffer, it’s slowed down by this interaction (cytoadhesion),” Karniadakis said. “This drastically changes the flow of blood in the brain, especially in the arterials and in the capillaries.”

Dimitry Fedosov, first author on the paper, worked on the research as a graduate student at Brown. He is now a postdoctoral researcher at the Institute of Solid State Research in Germany. Bruce Caswell, professor emeritus in the School of Engineering at Brown, contributed to the research. Subra Suresh, former dean of the engineering school at MIT and now director of the National Science Foundation, also contributed to the research.

The National Institutes of Health and the NSF funded the research.

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How do you cut a nanotube? Lots of compression

Researchers at Brown University and in Korea have described the dynamics behind cutting single-walled carbon nanotubes, cylindrical structures just 1/50,000th the width of a human hair. The tubes are compressed by potent sonic booms, causing them to buckle at certain points at helical, 90-degree angles. The finding could lead to better-quality nanotubes for potential use in automotive, electronics, optics and other fields. Results appear in the Proceedings of the Royal Society A.

Sound of slicing
High-intensity atomic-level sonic boomlets cause
nanotubes to buckle and twist at “compression-
concentration zones.”Credit: Kim Lab/Brown University

PROVIDENCE, R.I. — A pipefitter knows how to make an exact cut on a metal rod. But it’s far harder to imagine getting a precise cut on a carbon nanotube, with a diameter 1/50,000th the thickness of a human hair.

In a paper published this month in the British journal Proceedings of the Royal Society A, researchers at Brown University and in Korea document for the first time how single-walled carbon nanotubes are cut, a finding that could lead to producing more precise, higher-quality nanotubes. Such manufacturing improvements likely would make the nanotubes more attractive for use in automotive, biomedicine, electronics, energy, optics and many other fields.

“We can now design the cutting rate and the diameters we want to cut,” said Kyung-Suk Kim, professor of engineering in the School of Engineering at Brown and the corresponding author on the paper.

The basics of carbon nanotube manufacturing are known. Single-atom thin graphene sheets are immersed in solution (usually water), causing them to look like a plate of tangled spaghetti. The jumbled bundle of nanotubes is then blasted by high-intensity sound waves that create cavities (or partial vacuums) in the solution. The bubbles that arise from these cavities expand and collapse so violently that the heat in each bubble’s core can reach more than 5,000 degrees Kelvin, close to the temperature on the surface of the sun. Meanwhile, each bubble compresses at an acceleration 100 billion times greater than gravity. Considering the terrific energy involved, it’s hardly surprising that the tubes come out at random lengths. Technicians use sieves to get tubes of the desired length. The technique is inexact partly because no one was sure what caused the tubes to fracture.

Cutting a nanotube

Compression causes nanotubes to buckle and twist and eventually to lose atoms from their lattice-like structure.

Credit: Huck Beng Chew/Brown University


Materials scientists initially thought the super-hot temperatures caused the nanotubes to tear. A group of German researchers proposed that it was the sonic boomlets caused by collapsing bubbles that pulled the tubes apart, like a rope tugged so violently at each end that it eventually rips.

Kim, Brown postdoctoral researcher Huck Beng Chew, and engineers at the Korea Institute of Science and Technology decided to investigate further. They crafted complex molecular dynamics simulations using an array of supercomputers to tease out what caused the carbon nanotubes to break. They found that rather than being pulled apart, as the German researchers had thought, the tubes were being compressed mightily from both ends. This caused a buckling in a roughly five-nanometer section along the tubes called the compression-concentration zone. In that zone, the tube is twisted into alternating 90-degree-angle folds, so that it fairly resembles a helix.

That discovery still did not explain fully how the tubes are cut. Through more computerized simulations, the group learned the mighty force exerted by the bubbles’ sonic booms caused atoms to be shot off the tube’s lattice-like foundation like bullets from a machine gun.

“It’s almost as if an orange is being squeezed, and the liquid is shooting out sideways,” Kim said. “This kind of fracture by compressive atom ejection has never been observed before in any kind of materials.”

The team confirmed the computerized simulations through laboratory tests involving sonication and electron microscopy of single-walled carbon nanotubes.

The group also learned that cutting single-walled carbon nanotubes using sound waves in water creates multiple kinks, or bent areas, along the tubes’ length. The kinks are “highly attractive intramolecular junctions for building molecular-scale electronics,” the researchers wrote.

Huck Beng Chew, a postdoctoral researcher in Brown’s School of Engineering, is the first author on the paper. Myoung-Woon Moon and Kwang-Ryeol Lee, from the Korea Institute of Science and Technology, contributed to the research. The U.S. National Science Foundation and the Korea Institute of Science and Technology funded the work.

- Article by Richard Lewis, Brown Media Relations


This article has appeared in the following online publications:
http://www.nanowerk.com/news/newsid=19478.php
http://www.azonano.com/news.asp?newsID=21004
http://insciences.org/article.php?article_id=9738
http://www.futurity.org/top-stories/slice-nanotubes-with-sonic-booms/
http://www.nature.com/nature/journal/v468/n7326/full/468870d.html

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Bashevkin and Deisley Win 2010-2011 Doris M. and Norman T. Halpin Prize for Interdisciplinary Senior Capstone Projects

Thanks to the generosity of Doris M. and Norman T. Halpin, the Brown University School of Engineering Executive Committee provides research awards for exceptional undergraduates. Projects are awarded based on how well they demonstrate the power of interdisciplinary thought in engineering science and design. This year's winners of the Halpin Prize are Eli Bashivkin '11 and Daniel Deisley '11.

Excerpts from Eli's Halpin award nomination:
Eli has been interested in spaceflight since he was young, and has long know he has wanted to enter the aerospace engineering industry. Eli chose to attend Brown despite the lack of an aerospace program to take advantage of the open curriculum to design for himself a course of study leading to a broader technical background, to address the issues of technology in society, and to supplement his classroom education with team work and independent study projects. Professor Rick Fleeter is supervising his work on an innovative desktop scale hybrid rocket motor safe enough for development and use by students in an academic lab environment.

Eli has spent his entire time at Brown as a member of Brown's Formula SAE Design Team, a large interdisciplinary effort that combines engineering, production, and business to design and build a racecar from scratch each year. Eli has worked extensively on all aspects of this process, manufacturing components, contacting and working with sponsors, managing small teams, designed the brake, drivetrain, and powertrain subsystems of the vehicle.

Eli has defined an independent study project for this year to develop a low thrust, paraffin-fueled, hybrid rocket motor. Hybrid rocket motors are exceptionally simpler, and in many cases safer, than traditional liquid rocket engines, and thus can be used to reduce costs and put missions requiring propulsion in the hands of students and academic experimentalists. Paraffin has recently been recognized as an exceptional fuel for these applications. Tests have been done on large (50,000 Newton thrust) paraffin hybrid rocket engines used for launch into space, but little work has been conducted on how small these motors can be made to work. Eli's designs are at the 1 Newton level and below, with rocket motor diameter of a centimeter or two.


Excerpts from Daniel's Halpin award nomination:

Daniel's thesis on carbon nanotube EMI shielding is one that addresses issues emerging from the intersection between the fields of electrical engineering, material science, physics of phase transitions, and polymer chemistry. In his research, he will team up with members of the Laboratory of Emerging Technology to explore a novel carbon nanotube - polymer composite and its multifunctions, with his focus placed on its effectiveness and optimization for EMI (electromagnetic interference) shielding. The thesis will experimentally assess the incorporation of carbon nanotube networks into phase-changing polymer for EM shielding, leading to an optimized EMI shielding material that is ultra-thin, lightweight, corrosion and scratch resistant, flexible, and scalable. If successful, his work has the potential to pave the way for applications of the EMI-shielding composite in passport, bank card, and personnel ID card protection, as well as RFID enabled supply-chain management systems.

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Dr. Candace Lynch, Air Force Research Laboratory Engineer, Receives Harold Brown Award

Dr. Candace Lynch ScM'02, PhD'05, a senior scientist from Hanscom Air Force Base, Mass., received the 2010 Harold Brown Award on December 15 for her breakthrough research in pioneering new infrared technology that will augment aircraft defense and impact numerous Defense Department systems.

Dr. Lynch strengthened aircraft protection from heat-seeking missiles by developing counter-measure device technology involving laser material, specifically with the growth of orientation-patterned gallium arsenide.

The research physicist extended her technology to generate terahertz sources used in future imaging systems that enable the warfighter to see through brown-out conditions during helicopter landings or to image concealed weapons through clothing.

"Dr. Lynch's technology breakthrough is not only a national asset, but a testament to her dedication to science with a focus on national security," said Dr. David Jerome, the director of the sensors directorate in the Air Force Research Laboratory at Wright-Patterson Air Force Base, Ohio.

Dr. Lynch's efforts as part of the sensors directorate supported the science and technology necessary for superior U.S. air and space systems in intelligence, surveillance, reconnaissance, precision engagement and electronic warfare, Dr. Jerome said.

Having published more than 20 journal articles and eight conference presentations, Dr. Lynch received her bachelor of science from Massachusetts Institute of Technology in Cambridge, Mass., and both her master's degree and doctorate of philosophy from Brown University in Providence, R.I.

The Harold Brown Award recognizes significant achievement in research and development that led to or demonstrated promise of a substantial improvement in operational effectiveness of the U.S. Air Force. The award's namesake was a physicist who served as Air Force secretary from 1965 to 1969 and as Defense secretary from 1977 to 1981. Dr. Lynch is the first female recipient of the award since the program began in 1969.

Story courtesy of Tech. Sgt. Amaani Lyle
Secretary of the Air Force Public Affairs

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New Nanotechnology Patent: Material and Method for Promoting Tissue Growth U.S. Patent 7,833,283

Brown University Professors Thomas J. Webster and Karen M. Haberstroh were issued a patent (U.S. Patent No. 7,833,283) entitled “Material and Method for Promoting Tissue Growth” which describes a process to implement nanoscale surface features on polymers commonly used in regenerative medicine to increase the growth of numerous tissues. The patent describes how any polymer can be transformed to have surface features which mimic those of natural tissues to promote cell functions. It is currently being licensed to Nanovis, Inc. (www.nanovisinc.com).

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In the lab, engineer’s novel liquid provides a solid fix for broken bones

A bone-healing fluid that can be injected into breaks with a syringe shows such strong promise in lab testing, that it has been licensed from Brown by a Massachusetts biotech startup for further development.

By David Orenstein

A nonmetalic solutionNanomaterials engineer Thomas Webster is
developing alternatives to metals,which do not
occur naturally in the body and can cause
problems with surrounding tissue.Credit: Webster Lab/Brown University

Here’s the vision: an elderly woman comes into the emergency room after a fall. She has broken her hip. The orthopaedic surgeon doesn’t come with metal plates or screws or shiny titanium ball joints. Instead, she pulls out a syringe filled with a new kind of liquid that will solidify in seconds and injects into the break. Over time, new bone tissue will take its place, encouraged by natural growth factors embedded in the synthetic molecules of the material.

Although still early in its development, the liquid is real. In the Brown engineering lab of professor Thomas Webster it’s called TBL, for the novel DNA-like “twin-base linker” molecules that give it seemingly ideal properties. The biotech company Audax Medical Inc., based in Littleton, Mass., has just announced an exclusive license of the technology from Brown. It brands the technology as Arxis and sees similar potential for repairing broken vertebrae.

“The reason we’re excited about this material is because it gets us away from metals,” Webster said. “Metals are not in us naturally and they can have a lot of problems with surrounding tissues.”

In some of his work, Webster employs nanotechnology to try to bridge metals to bone better than traditional bone cement. But TBL is an entirely new material, co-developed with longtime colleague and chemist Hicham Fenniri at the University of Alberta. Fenniri synthesized the molecules, while Webster’s research has focused on ensuring that TBL becomes viable material for medical use.

Buttressing bonesTwin-based linker molecules, top left, self-assemble
into six-molecule rings. Stacked in a tube shape, the
 rings of molecules not only provide a new scaffold
for bone growth, but can also store growth factors
and helpful drugs inside.
    Credit: Webster Lab/Brown University

The molecules are artificial, but made from elements that are no strangers to the body: carbon, nitrogen, and oxygen. At room temperature their aggregate form is a liquid, but the material they form solidifies at body temperature. The molecules look like nanoscale tubes (billionths of a meter wide), and when they come together, it is in a spiraling ladder-shaped arrangement reminiscent of DNA or collagen. That natural structure makes it easy to integrate with bone tissue.

In the space within the nanotubes, the team, which includes graduate student Linlin Sun, has managed to stuff in various drugs including antibiotics, anti-inflammatory agents, and bone growth factors, which the tubes release over the course of months. Even better, different recipes of TBL, or Arxis, can be chemically tuned to become as hard as bone or as soft as cartilage, and can solidify in seconds or minutes, as needed. Once it is injected, nothing else is needed.

“We really like the fact that it doesn’t need anything other than temperature to solidify,” Webster said. Other compounds that people have developed require exposure to ultraviolet light and cannot therefore be injected through a tiny syringe hole. They require larger openings to be created.


Liquid provides a solid fix for broken bones from Brown PAUR on Vimeo.


For all of TBL’s apparent benefits, they have only been demonstrated in cow bone fragments in incubators on the lab bench top, Webster said. TBL still needs to be proven in vivo and, ultimately, in human trials. Part of the agreement with Audax will include support to continue the material’s clinical development. Audax research and development director Whitney Sharp, a Brown alumna (Sc.B., 2008; Sc.M., 2009), is now working with Webster’s group.

“They see the future where hopefully we will get to the point where we won’t be implanting these huge pieces of metal into people,” Webster said. “Instead we’ll be implanting things through a needle that could be used to heal a hip that’s more natural.”

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