More Nanomanipulator stories > Endeavors, Spring 2000

The Whole Elephant

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Why People are
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Spreading it Around

Gearing up for
Nanomachines

Spreading it Around
by Mark Briggs

Diane Sonnenwald, assistant professor of information science, has been studying the use of the nanoManipulator for collaboration over distances—or working distributively. Some participants found joint experiments easier to conduct from far away rather than up close. Call it a case of personal space if you will.

“Some participants said that in some respects it was easier working distributively because they didn’t have to do a lot of social negotiation,” Sonnenwald says. “I take that as an indication we’re doing things the right way with the technology.”

The distributive version of the nano-Manipulator includes audio and video to allow scientists to talk with their collaborators and watch each other’s gestures. (Sonnenwald says that scientists talk with their hands more than other people typically do.) The software features different types of cursors so that each scientist can easily distinguish what the other is pointing to on the screen.

The study’s participants—juniors and seniors in biology, physics, chemistry, and chemical engineering—are replicating experiments led by Martin Guthold, a post-doctoral fellow in computer science and physics. Sonnenwald also interviews scientists who are using the nanoManip-ulator now and those who hope to use the distributive version. Her research is funded by the National Institutes of Health (NIH). Traditionally, NIH funds certain labs around the country that have specialized scientific instruments, which are very expensive. Scientists then fly around to these locations to use these instruments. NIH wants to know whether it is feasible to provide distributive access to these sites.

Also contributing to this project are Mary Whitton, Research Assistant Professor of computer science, and information science graduate students Kelly Maglaughlin, Ron Bergquist, Leila Plummer, Atsuko Negisha, Ramkumar Parameswaram, and Eileen Kupstas-Soo, and computer
scientists Russ Taylor, Aaron Helser, Tom Hudson, Kevin Jeffay, and Don Smith.

Gearing up for Nanomachines
by Neil Caudle

Mike Falvo knows a gear when he sees it, even if each gear tooth is as small as a single atom. Falvo has discovered that when he aligns a carbon nanotube in a particular way on a graphite surface, the atoms of the tube lock into the atoms of the surface like gear teeth. Once the tube is “in gear” this way, it seems to roll as a pencil does, retaining its alignment. But if the tube is not aligned at exactly 60 degrees (the angle of the hexagons formed by its atomic structure), it will slide instead of rolling. For Falvo, this is far more than an exercise in curiosity. One of the necessary elements of any kind of nanomachine—a tiny switch, for instance—would be parts that could retain their intended alignment as they moved.

Falvo, a research assistant professor in physics and astronomy, worked with Rich Superfine and the nanoManipulator project during graduate school and has helped to conduct some of its most notable experiments, including those which showed how nanotubes buckle without breaking, even when they are bent almost double. In 1997, this work made the cover of the journal Nature.

Falvo is intrigued by the movement of things at the nanoscale, which presents its own set of rather exotic physical laws. “Gravity, for instance, really isn’t relevant at this scale,” Falvo says. “You can turn your sample upside down, and it won’t matter a bit. At the nanoscale, what dominates is stickiness. Because of electrodynamic forces and capillary forces, everything sticks to everything.”

Liquid Memory
by Neil Caudle

Chris Dwyer, a graduate student in computer science, has ventured into a nanoscience research project so technically diverse that no one on his thesis committee understands it all. The goal? To create, in a small vial of liquid, enough computing power to equal all of the Pentium processors ever made, or enough memory to, say, store all of the individual genetic information for 10 billion people.

His methods are confidential, for now, but the gist is this: Dwyer plans to borrow Nature’s system for encoding and copying information. He envisions tiny, biochemically assembled computing systems that could be replicated into an almost limitless electrochemical architecture.

“A cell can do all kinds of things that are being done with so-called artificial intelligence,” Dwyer says, “but it does it chemically in such a small package—beautifully and elegantly.”

Leandra Vicci, director of the Microelectronic Systems Laboratory in computer science, says, “When Chris first came and talked to me about this, I was very skeptical. Now, I believe—in principle—that this could work, encoding instructions using biological material. What you’re looking at is mass production on a scale that makes microelectronics look like a manual transmission.”

Dwyer is not the only one racing to harness the computing power of biochemistry. Across the country, several powerful research groups are on a similar quest. But Dwyer thinks his approach has several advantages, and that he’s in the right place at the right time to make it work.

Sean Washburn, Dwyer’s mentor from materials science, says the project’s ambitious scope demands an exceptional student. “Chris is brilliant and fearless, two qualities that are necessary for the work he’s doing. He knows how to think for himself, and he is willing to take risks.”

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