Archive for February, 2006

Critical Design

Monday, February 27th, 2006

I spent an interesting afternoon last Tuesday in the Royal College of Art spending some time with the students on the Interaction Design course, who are just beginning a project on nanotechnology. This department began life focusing on Computer Related Design, applying the lessons of fine art and graphic design to human centred design for computer interfaces, but it’s recently broadened its scope to a wider consideration of the way people and societies interact with technology. It’s in this context that the students are being asked to visualise possible nanotechnology-based futures.

My host for the visit was the Head of Department, Tony Dunne, the author of (among other works) Hertzian tales and Design Noir. He uses the space between industrial design, conceptual art and social theory to question the relationship between technology and society; on his appointment to the RCA he wrote “Interaction Design can be a test space where designers engage with different technnologies (not just electronics) before they enter the market place, exploring their possible impact on everyday life through design proposals – from a variety of perspectives: commercial, aesthetic, functional, critical, even ethical. I believe we need to educate designers to a higher level than we presently do, if they are to have a significant and meaningful role to play in the 21st Century and not just sit at the margins producing pleasant distractions”

To see why this approach to design might be useful for nanotechnology, take a look at the Nanofactory animation made by John Burch and Eric Drexler to illustrate their vision of the future of nanotechnology. Making no judgements for the moment about its technical feasibility, its worth looking at the symbolism of this vision. What’s striking about it is how amazingly conservative it is. The nano-fabricator itself looks like an upmarket bread-making machine, while the final product is a palm-top computer that could in design terms have come from your local PC World. It’s worth contrasting this vision with the much more radical vision of manufacturing outlined in Drexler’s original book Engines of Creation, which imagined a rocket motor growing, as if from a seed, in a huge tank of milky fluid. I’m sure this retreat to a more conservative, and less challenging, vision, was deliberate, and part of the attempt to defuse the”grey goo” controversy. If we are going to be prepared for what technological change brings us, we are going to need some more challenging visions of future artefacts, and I look forward to seeing the radical concepts that the design students come up with.

Death, life, and amyloids

Monday, February 20th, 2006

If you take a solution of a protein, an enzyme, say, and heat it up, it unfolds. The beautifully specific, three dimensional structure, that underlies the workings of the enzyme or molecular machine, melts away, leaving the protein in an open, flexible state. What happens next depends on how concentrated the protein solution is. Remarkably, if the solution is dilute enough that different protein molecules don’t significantly interact, they’ll refold back into their biologically active state. This discovery of reversible refolding won Christian Anfinsen the 1972 Nobel Prize for chemistry; it was these experiments that established that the three dimensional structure of proteins in their functional form is wholly specified by their one-dimensional sequence of amino acids via the remarkable, and still not wholly understood, example of self-assembly that is protein folding. But if the proteins are in a more concentrated solution – the concentration of proteins in egg white or milk whey, for example – then as they cool they don’t fold properly. Instead they interact to make a sticky mess, apparently without biological functionality – you can’t hatch a chick out of a boiled egg.

But over the last fifteen years, it’s become clear that misfolded proteins are of huge biological and medical significance. Previously, the state that many proteins misfold into was believed to be an uninteresting, unstructured mish-mash. But now it’s known that, on the contrary, misfolded proteins often form a generic, highly ordered structure called an amyloid fibril. These are tough, stiff fibres, each about 10 nm wide and up to a few microns in length, in which the protein molecules are stacked together, linked by multiple hydrogen bonds, in extended, crystal-like structures called beta-sheets. The medical significance of these amyloid fibrils is huge; it’s these misfolded proteins that are associated with a number of serious and incurable diseases, like Alzheimers, type II diabetes and Creutzfield-Jacob disease. The physical significance is that there’s an increasingly influential school of thought (led by Chris Dobson of Cambridge) that the amyloid state is actually the most stable state of virtually all proteins. If you take this view to the limit, it implies that all organisms would eventually and inevitably succumb to amyloid diseases if they lived long enough.

This sinister side of amyloid fibrils hasn’t stopped people looking for some positive uses for them. Some researchers, like Harvard’s Susan Lindquist, have thought about using them as templates to make nanowires, though in my view they have several disadvantages compared to other potential biological templates like DNA. But biology is full of surprises, and the discovery by a Swedish group a few years ago that a misfolded version of the milk protein alpha-lactalbumin has a potent anti-cancer effect (full article available, without subscription, here) is certainly one of these. They speculate that this conversion takes place inside the stomach of new-born babies, helping protect them against cancer, and these molecules have already undergone successful clinical trials for treatment of skin papillomas. My children are still young enough for me to remember well the consistency of posset (as we in England delicately call regurgitated baby milk) so the idea of this as a clinicallly proven defense against cancer is rather odd.

But even stranger than this is a story in this weeks Economist, implicating amyloids in the ultimate origin of life itself. This reports from a meeting held at the Royal Society last week about the origin of life, and discusses a theory by the Cardiff biologist Trevor Dale. He takes inspiration from Cairns-Smith, the originator of a brilliant but so far unverified theory of the origin of life which suggests that life began by the templated polymerisation of macromolecules on the surfaces of clay platelets. Dale takes this idea, but suggests that the original macromolecule was RNA, and the surface, rather than being a clay platelet, was a protein amyloid fibril. This then naturally gives rise to the idea of co-evolution of nucleic acids and proteins, rather than requiring, as more popular theories do, a separate, later, stage in which an RNA-only form of life recruits proteins. The theory is described in an pre-publication article in the Journal of Theoretical Biology (abstract only without a subscription). I’m not sure I’m entirely convinced, but who can say what other suprises the amyloid state of proteins may yet spring.

More about Nanohype

Monday, February 13th, 2006

Having spent 9 hours in aeroplanes yesterday (not to mention another 6 hours hanging about in a snowy Philadelphia airport waiting for a delayed connection) I have at least had a chance to catch up with some reading. This included two nano- books, one of which was David Berube‘s “Nanohype“. The other (which exemplifies the phenomenon of Berube’s title) was “The Dance of Molecules: how nanotechnology is changing our lives“, by Ted Sargent. I’m reviewing Sargent’s book for Nature, so I’ll save my views on it for later.

“Nanohype” isn’t exactly the usual airport book, though. It’s a rather dense, and extremely closely referenced, account of the way nanotechnology moved from being a staple of futurists and science fiction writers to being the new new thing for technophilic politicians and businessmen, and a new object of opposition for environmentalists and anti-globalisers. For those of us fascinated by the minutiae of how the National Nanotechnology Initiative got going, and of the ways the Nanobusiness Alliance influenced public policy in the USA, it’s going to be the essential source.

The book’s title makes Berube’s basic position pretty clear. Almost everyone involved has some ulterior motive for overstating how revolutionary nanotechnology is going to be, how much money it’s going to make, or the scale of the apocalypse it is going to lead to. Scientists need grants, companies need venture capital, campaigning organisations need publicity and the donations that follow. Not everyone is a huckster, but those that remain idealists end up so divorced from reality that they end up attracting Berube’s (no doubt unwelcome) sympathy. Sometimes the search for low motives leads from bracing cynicism to the brink of absurdity, such as his suggestion that anti-globalisation activist Zak Goldsmith’s opposition to genetic modification of food derives from his wife’s business interests in organic food. This seems a little unlikely, given Goldsmith’s reported £300 million inherited fortune. But Berube’s refusal to take things at face value is a refreshing starting point.

The book has a competent and fairly complete overview of those commercial applications ascribed to nanotechnology, but one thing this book is not about is science. I think this is a pity – there’s an interesting story to be told both about the ascendance of the nanotechnology label amongst academic scientists, and of the resistance, suspicion and cynicism that this has bred in some quarters. But this will have to wait for another chronicler; curiously even giants of academic nanoscience, like Rick Smalley and George Whitesides, appear here as antagonists for the Drexler vision rather than for their own considerable achievements.

Of course, this is a book about politics, not science. It’s about the high-level politics around science funding, the politics of the financial markets, the politics of the campaigning organisation. But despite this political theme, it’s curiously light on ideologies. When we are talking about the societal and ethical implications of nanotechnology, we’re talking about competing visions of the future, competing ideologies. It is striking that many of the protagonists in the nanotechnology debates are driven by very strongly held, and sometimes far from mainstream, creeds. There’s the millenarianism of the transhumanists, the characteristically American libertarianism exemplified by blogger and nano-enthusiast Glenn Reynolds, and on the opposition side the strange blend of radical anti-capitalism, green politics and reactionary conservatism that underlies the world-view of Zak Goldsmith (particularly interesting in the UK now that a newly resurgent conservative opposition party has charged Goldsmith with reviewing its environmental policies). I would like to see a much closer analysis of the deeper reasons why nanotechnology seems to be emerging as a focus of these more profound arguments, but perhaps it’s still too early for this.

Another draft nano-taxonomy

Friday, February 10th, 2006

It’s clear to most people that the term nanotechnology is almost impossibly broad, and that to be useful it needs to be broken up into subcategories. In the past I’ve distinguished between incremental nanotechnology, evolutionary nanotechnology and radical nanotechnology, on the basis of the degree of discontinuity with existing technologies. I’ve been thinking again about classifications, in the context of the EPSRC review of nanotechnology research in the UK; here one of the things we want to be able to do is to be able to classify the research that’s currently going on. In this way it will be easier to identify gaps and weaknesses. Here’s an attempt at providing such a classification. This is based partly on the classification that EPSRC developed last time it reviewed its nanotechnology portfolio, 5 years ago, and it also takes into account the discussion we had at our first meeting and a resulting draft from the EPSRC program manager, but I’ve re-ordered it in what I think is a logical way and tried to provide generic definitions for the sub-headings. Most pieces of research would, of course, fit into more than one category.

Enabling science and technology
1. Nanofabrication
Methods for making materials, devices and structures with dimensions less than 100 nm.
2. Nanocharacterisation and nanometrology
Novel techniques for characterisation, measurement and process control for dimensions less than 100 nm.
3. Nano-modelling
Theoretical and numerical techniques for predicting and understanding the behaviour of systems and processes with dimensions less than 100 nm.
4. Properties of nanomaterials
Size-dependent properties of materials that are structured on dimensions of 100 nm or below.
Devices, systems and machines
5. Bionanotechnology
The use of nanotechnology to study biological processes at the nanoscale, and the incorporation of nanoscale systems and devices of biological origin in synthetic structures.
6. Nanomedicine
The use of nanotechnology for diagnosing and treating injuries and disease.
7. Functional nanotechnology devices and machines
Nanoscale materials, systems and devices designed to carry out optical, electronic, mechanical and magnetic functions.
8. Extreme and molecular nanotechnology
Functional devices, systems and machines that operate at, and are addressable at, the level of a single molecule, a single atom, or a single electron.
Nanotechnology, the economy, and society
9. Nanomanufacturing
Issues associated with the commercial-scale production of nanomaterials, nanodevices and nanosystems.
10. Nanodesign
The interaction between individuals and society with nanotechnology. The design of products based on nanotechnology that meet human needs.
11. Nanotoxicology and the environment
Distinctive toxicological properties of nanoscaled materials; the behaviour of nanoscaled materials, structures and devices in the environment.

All comments gratefully received!

From the gallery

Wednesday, February 8th, 2006

For no particular reason other than it is a really nice image, here’s a picture from the Sheffield Polymer Physics Group. It’s an AFM image of a thin film of a block copolymer – a molecule with a long section that can crystallise (poly ethylene oxide), attached to a shorter length of a non-crystallisable material (poly vinyl pyridine). What you can see is a crystal growing from a screw dislocation. The steps have a thickness of a single molecule folded up a few times.

AFM image of a block copolymer growing from a screw dislocation

Image width 20 microns. Image by Dr Cvetelin Vaslilev, image post-treatment by Andy Eccleston.

Letters from Nano-land

Tuesday, February 7th, 2006

What academic journals should one read to get the latest news about nanotechnology research? This isn’t as an easy a question to answer as one might think, and this difficulty reflects the fact that nanoscience and nanotechnology have still not really gelled into a coherent scientific culture. So nanotechnology done by physicists will often end up in physics journals (Physical Review Letters being the most prestigious), while that done by chemists will similarly end up in chemistry journals. The nearest thing we have to specialised nanotechnology journals are the general materials science journals like Nature Materials and Advanced Materials, both of which are essential reading. A recent addition to this space, though, is explictly pitching to be the nanotechnology journal of choice – this is the American Chemical Society’s journal Nano Letters. This is winning a lot of friends in the nanoscience community; the time between papers being submitted and them appearing is very short, which appeals to impatient authors, and the editorial board is a list of some of the most distinguished nanoscientists anywhere. And the impact factor – a crucial measure of where a journal is in the scientific pecking order, defined by the average number papers appearing in the journal are cited by other papers – is high. Nature Materials is still at the top of the pile (not counting Nature and Science, of course), with an impact factor of 13.53, but Nano Letters, at 8.45, has already shaded ahead of Advanced Materials, at 8.08. The long-established Institute of Physics journal Nanotechnology trails a long way behind at 3.32. Journals, and their editorial policies, are important in defining emerging fields, so it’s interesting to take a snapshot of how the Nano Letters editors see the field, on the basis of the papers published in the current edition.

Carbon nanotubes are clearly still objects of nanofascination, accounting for five out of the twenty five papers in the issue. It’s largely the electronic properties of the nanotubes that excite, rather than their mechanical properties, and this theme of nanoelectronics is continued with another five papers on semiconductor nanowires. Soft nanotechnology and bio-nanotechnology is an important theme, accounting for eleven papers. There’s some overlap; a couple of papers use the self-assembling properties of biological molecules like DNA and peptides to guide the assembly of inorganic nanotubes and nanowires. Experiment dominates over theory, with only three purely theoretical papers. Most of the papers are quite a long way from any applications. The work that’s closest to market includes a paper on the use of quantum dots for magnetic resonance imaging, one on using titanium dioxide nanoparticles for solar generation of hydrogen. At the other end of the scale, there’s one paper on the use of the scanning tunneling microscope to mechanically position and react individual molecules on a surface.

It’s interesting to ask where, geographically, the papers comes from. As one would expect from a USA-based journal, the largest contribution comes from the USA, with 56% of the papers. Europe accounts for 36%, with a fair spread of countries represented, while the remainder come from Canada. Interestingly, this issue contains no contributions at all from the far east. In fact, over the whole of 2005 only 2% of the papers in Nano Letters came from China.

I’m not entirely sure what all this means, but one thing that strikes me is there’s relatively little relationship between this (small) sample of what the academic nano- community thinks is exciting work, and what is currently being commercialised by industry. An optimist would take this as a sign that there was a significant pipeline of work that will be coming ready to commercialise maybe 5-10 years from now.

Scenarios for the future of transport

Wednesday, February 1st, 2006

The UK government established a new horizon-scanning unit in its Office and Science and Technology a few years ago, and this has now issued its first report. This takes a look at likely scenarios for transport infrastructures over the next fifty years, but since transport and communications are so central to our economy these scenarios form a fairly comprehensive look at how new technology might change the way we live. In particular, they cover three big questions about technology and the future:

  • Where will the energy that currently underwrites our lifestyle in the developed world come from?
  • How will we exploit the growing amount of information processing and communication power we will have at our disposal?
  • Will the world carry on its trend to centralisation in manufacturing and energy generation, or will we see a switch to increasingly decentralised modes of production?
  • The web-site has links to lot of excellent material, including many interesting, specially commissioned background papers, but perhaps the most interesting things are the Project overview (54 page PDF), and the Scenarios (89 page PDF). The latter bring the subject to life with four plausible, but highly contrasting, scenarios for how things might turn out.

    The techno-optimist’s scenario is called “Perpetual motion”. Here it’s assumed that technology has managed to overcome the problems of sustainable energy with some combination of the hydrogen economy, nuclear fuels, coal and carbon sequestration. Everything and everyone is plugged in to the information grid, and the major problem the world faces is workplace stress. There’s a green nirvana too: “Urban colonies” imagines a future of sustainable urbanisation, where personal transport is discouraged by heavy taxation. Energy comes from microgrids, there is universal recycling and reuse. People are prosperous, but the economy revolves around fewer goods and more services. Iin short, it’s a vision of the future in which everywhere looks like Copenhagen, rather than Seoul. But, on the principle that the statistically most accurate way of predicting the weather tomorrow is to look out of the window today, what is considered the most likely scenario is called “Good intentions”. This is a world in which hard decisions have been put off until too late. Transport is both highly congested and highly priced; there’s been some progress with biofuels but accelerating climate change is leading to increasingly frequent weather disasters. Both prosperity and personal freedom are compromised.

    Techno-optimists think that the accelerating pace of technological advances will determine how the world changes, while green-tinged social liberals believe that the future can be deliberately shaped by human, democratic values. There is a third, much uglier, possibility; that we will be unable to prevail over overwhelming societal strains imposed by external shocks. This is the world of the most pessimistic scenario, “Tribal trading”. Here an early end to the era of cheap energy has stripped the veneer from our globalised world. A decline in oil production has led to spiralling oil prices. Economic depression has ended with the near-complete collapse of world and national financial systems, with resource wars and environmental disasters adding to the gloom. It’s a world of walls and borders and vegetable gardens, in which the 90′s experience of Cuba offers some of the best coping strategies. Some technology survives, and with travel over even modest distances prohibitively difficult and expensive, robust communications are more important than ever. For advice, we’re directed to the poet Gary Snyder:

    “What is to be done? Learn to be more self-reliant, reduce your desires, and take care of yourself and your family”.