In 2008, two memristor papers were published in Nature and Nature Nanotechnology, respectively. In the first (Nature, May 2008 [article still behind a paywall], a team at HP Labs claimed they had proved the existence of memristors (a fourth member of electrical engineering’s ‘Holy Trinity of the capacitor, resistor, and inductor’). In the second paper (Nature Nanotechnology, July 2008 [article still behind a paywall]) the team reported that they had achieved engineering control.

I mention this because (a) there’s some new excitement about memristors and (b) I love the story (you can read my summary of the 2008 story here on the Nanotech Mysteries wiki).

Unbeknownst to me in 2008, there was another team, located in Japan, whose work  on slime mould inspired research by a group at the University of California San Diego (UC San Diego)  which confirmed theorist Leon Chua’s (he first suggested memristors existed in 1971) intuition that biological organisms used memristive systems to learn. From an article (Synapse on a Chip) by Surf daddy Orca on the HPlus magazine site,

Experiments with slime molds in 2008 by Tetsu Saisuga at Hokkaido University in Sapporo sparked additional research at the University of California, San Diego by Max Di Ventra. Di Ventra was familiar with Chua’s work and built a memristive circuit that was able to learn and predict future signals. This ability turns out to be similar to the electrical activity involved in the ebb and flow of potassium and sodium ions across cellular membranes: synapses altering their response according to the frequency and strength of signals. New Scientist reports that Di Ventra’s work confirmed Chua’s suspicions that “synapses were memristors.” “The ion channel was the missing circuit element I was looking for,” says Chua, “and it already existed in nature.”

Fast forward to 2010 and a team at the University of Michigan led by Dr. Wei Lu showing how synapses behave like memristors (published in Nano Letters, DOI: 10.1021/nl904092h [article behind paywall]). (Fromthe  HPlus site article)

Scientific American describes a US military-funded project that is trying to use the memristor “to make neural computing a reality.” DARPA’s Systems of Neuromorphic Adaptive Plastic Scalable Electronics Program (SyNAPSE) is funded to create “electronic neuromorphic machine technology that is scalable to biological levels.”

I’m not sure if the research in Michigan and elsewhere is being funded by DARPA (the US Dept. of Defense’s Defense Advanced Research Project Agency) although it seems likely.

In the short term, scientists talk about energy savings (no need to reboot your computer when you turn it back on). In the longer term, they talk about hardware being able to learn. (Thanks to the Foresight Institute for the latest update on the memristor story and the pointer to HPlus.) Do visit the HPlus site as there are some videos of scientists talking about memristors and additional information (there’s yet another team working on research that is tangentially related).

Commercializing academic research in US

Thanks to Dave Bruggeman at the Pasco Phronesis blog who’s posted some information about a White House Request for Information (RFI) on commercializing academic research. This is of particular interest not just because of the discussion about innovation in Canada but also because the US National Nanotechnology Initiative’s report to PCAST (President’s Council of Advisors on Science and Technology, my comments about the webcast of the proceedings here). From the Pasco Phronesis posting about the NNI report,

While the report notes that the U.S. continues to have a strong nanotechnology sector and corresponding support from the government. However, as with most other economic and research sectors, the rest of the world is catching up, or spending enough to try and catch up to the United States.

According to the report, more attention needs to be paid to commercialization efforts (a concern not unique to nanotechnology).

I don’t know how long the White House’s RFI has been under development but it was made public at the end of March 2010 just weeks after the latest series of reports to PCAST. As for the RFI itself, from the Pasco Phronesis posting about it,

The RFI questions are organized around two basic concerns:

• Seeking ideas for supporting the commercialization and diffusion of university research. This would include best practices, useful models, metrics (with evidence of their success), and suggested changes in federal policy and/or research funding. In addition, the RFI is interested in how commercialization ecosystems can be developed where none exist.

• Collecting data on private proof of concept centers (POCCs). These entities seek to help get research over the so-called “Valley of Death” between demonstrable research idea and final commercial product. The RFI is looking for similar kinds of information as for commercialization in general: best practices, metrics, underlying conditions that facilitate such centers.

I find the news of this RFI a little surprising since I had the impression that commercialization of academic research in the US is far more advanced than it is here in Canada. Mind you, that impression is based on a conversation I had with a researcher a year ago who commented that his mentor at a US university rolled out more than 1 start up company every year. As I understand it researchers in Canada may start up one or two companies in their career but never a series of them.

Carbon nanotubes, is exposure ok?

There’s some new research which suggests that carbon nanotubes can be broken down by an enzyme. From the news item on Nanowerk,

A team of Swedish and American scientists has shown for the first time that carbon nanotubes can be broken down by an enzyme – myeloperoxidase (MPO) – found in white blood cells. Their discoveries are presented in Nature Nanotechnology (“Carbon nanotubes degraded by neutrophil myeloperoxidase induce less pulmonary inflammation”) and contradict what was previously believed, that carbon nanotubes are not broken down in the body or in nature. The scientists hope that this new understanding of how MPO converts carbon nanotubes into water and carbon dioxide can be of significance to medicine.

“Previous studies have shown that carbon nanotubes could be used for introducing drugs or other substances into human cells,” says Bengt Fadeel, associate professor at the Swedish medical university Karolinska Institutet. “The problem has been not knowing how to control the breakdown of the nanotubes, which can caused unwanted toxicity and tissue damage. Our study now shows how they can be broken down biologically into harmless components.”

I believe they tested single-walled carbon nanotubes (CNTs) only as the person who wrote the news release seems unaware that mutil-walled CNTs also exist. In any event, this could be very exciting if this research holds up under more testing.