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Biotech Science Technology

Nanotech Motors, Biotransistors, DNA Fractals 96

FleaPlus writes "The American Institute of Physics has a news bulletin describing a couple of interesting nanotech advances. The first is the smallest electric motor in the world, made by Alex Zettl's group at UC Berkeley. The second is a single-protein wet biotransistor. Additionally, Technology Research News reports on algorithmic self-assembly of DNA Sierpinski triangles, by Erik Winfree's group at Caltech."
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Nanotech Motors, Biotransistors, DNA Fractals

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  • Coral Cache (Score:3, Informative)

    by Anonymous Coward on Sunday April 10, 2005 @03:37PM (#12195531)
    Take it easy on those Berkley servers. Coral Cache:

    Computer-generated movie [nyud.net] shows an artist's conception of the operation of the relaxation oscillator, and a possible application. Created by Kenny Jensen

    TEM video [nyud.net] data showing an operating relaxation oscillator, with explanatory text overlaid.
  • Are sooo March 2005. Wake me up when they develop a single protein dry biotransistor.
  • Miniature motors (Score:3, Interesting)

    by karn096 ( 807073 ) on Sunday April 10, 2005 @03:45PM (#12195576)
    Wasn't there an article about mini-turbines also, that researchers were planning on using to power small devices, I'm wondering if these nano-motors could be used in the same regard.
    Maybe I should go RTFA now.
  • by A Sea and Cake ( 874933 ) on Sunday April 10, 2005 @03:55PM (#12195644)
    The first is the smallest electric motor in the world, made by Alex Zettl's group at UC Berkeley. Eventually, this will go into the world's smallest electric planer, which will be used, in part, to create the world's smallest violin. Tragically, this wonder of design will be crushed between the fingers of Steve Buscemi.
  • by katana ( 122232 ) on Sunday April 10, 2005 @03:59PM (#12195660) Homepage
    Okay, I'm not a scientist, but why would you want a *smaller* vibrating dildo?
  • nano contact lenses that enable me to see through clothes!!! now that would be an interesting nanotech advance.
  • How does it work ? (Score:5, Interesting)

    by karvind ( 833059 ) <karvind@NoSPAM.gmail.com> on Sunday April 10, 2005 @04:17PM (#12195746) Journal
    The peak pulsed power is 20 microwatts. Considering that the device is less than 200 nm on a side, the power density works out to about 100 million times that of the 225 hp V6 engine in a Toyota Camry.

    I am not sure if I understand the power density claims. Here is a simple calculation. 20 microwatts in cube of 200nm x 200nm x 200nm will be 20 microwatts in 8 x 10^(-15) cm^3 volume. That will be a power density of 2.5 x 10^9 Watts/cm^3.

    Sun's fusion power density is only ~ 2.5x10^(-4) Watts/cm^3 with core temperature around 15.7 x 10^6 K. I can understand that we wouldn't be generating the heat at peak density, but if we generate that high power desnity in nanomechanical system for even any reasonable time - wouldn't it just evaporate unless we find a very fast way of removing the power efficiently ?

    • if we generate that high power desnity in nanomechanical system for even any reasonable time - wouldn't it just evaporate unless we find a very fast way of removing the power efficiently ?

      Ummmm... I'd guess that the energy is being used as kinetic or mechanical energy - not heat. If I hadn't gotten into a Sunday Afternoon cocktail or two, I'd figure out the efficiency of this machine - I bet it'd be truly impressive.

      Soko
    • Well, i dont really have the mood to calculate, but small things are VERY easy to cool.
      For example, your cpu die is 1cm^2 big, but all the heat is only generated in a few um height.
      Similar here: When downscaling, volume goes down with a d^3, surface are only with d^2. So there very small parts have a HUGE surface to volume ratio and are very easily cooled.
      Not to mention that there is a direct cooling path to the substrate they are build on.

    • by Anonymous Coward
      I am not sure if I understand the power density claims.

      That's because they're really not meaningful. You can't compare it to the Sun (or a Toyota), because 'power density' in a macroscopic sense isn't the same thing as in the microscopic sense.

      For example, if you wanted to, you could calculate the 'power density' of a single atom or an electrical current, dividing the current power by the volume of the conducting electrons. That'd certainly give you a very high number - electrons are small - but not a ve
  • by bcrowell ( 177657 ) on Sunday April 10, 2005 @04:20PM (#12195759) Homepage
    Nanotechnology has gotten a reputation for being a flaky area of research. Part of the problem is that the word "nanotech" sounds cool, so people tend to use it without defining what they mean. Eric Drexler [wikipedia.org] originally defined it in terms of machines that worked at the molecular level, i.e., on scales of a few nanometers. The problem is that there are fundamental reasons why it's extremely difficult to construct machines on that scale, and in the 20 years since he published Engines of Creation, basically nothing has happened to realize his original vision. Meanwhile, people have been making smaller and smaller machines via techniques that would never be able to scale down to the scales Drexler had in mind. The wikipedia article [wikipedia.org] distinguishes between "nanotechnology" and "molecular nanotechnology." The Berkeley group's motor, for instance, is clearly on a scale (hundreds of nm) that is not molecular nanotechnology.
    • by Anonymous Coward
      And here I thought it referred to anything written with a reasonable text editor. I'd better remove that nanotech engineer line on my CV then...
    • Um, the DNA assembly of Sirepinski triangles is definately a nanoscale operation.
    • by Goldsmith ( 561202 ) on Sunday April 10, 2005 @06:05PM (#12196248)
      Drexler's book was conceptually great and really pumped a lot of interest of the subject into the general public (his second is another thing). However, Engines of Creation makes a few assumptions about the molecular world which have been found to be incorrect. Diamondoids are not as stable a form of carbon at the nano scale as he thought, and materials are inherantly different from the bulk at the nanoscale. For example, a relatively inert metal such as gold becomes extremely reactive when clumped into just a few isolated atoms. The reason nothing has happened to realize Drexler's original vision is that it did not work, his detals were wrong. It's not as easy as drawing lines between carbon atoms to make the shape you want. Since then, Drexler has refined his own definition of nanotechnology into something which can be described as artificial biology in arbitrary environments. This is a common definition of nanotechnology among the majority of people who study it. Like Drexler, most of the people studying nanotechnology come from a biology background. They tend not to like the atomic or solid state approaches used by physicists and engineers, so they call their work "molecular nanotechnology" to differentiate themselves.

      Zettl is a physicist, and comes at things from a very different perspective. I had the opportunity to see this research presented at an invited talk a few weeks ago at the last APS meeting. It is most definitely nanotechnology on the level of single atoms. Let me explain:

      Their "motor", as presented at APS, consists of a resevior of indium atoms at one end of a carbon nanotube, and an indium crystal on the other end. By driving a current through the nanotube in conjuction with heating from the TEM electron beam, they are able to move the indium from the resevior to the crystal and back. The atoms move very quickly, they do not have the time resolution in the TEM to see them. The crystal, on the other hand, grows very slowly, and they are able to see individual atomic layers being deposited on this crystal which is only a few nanometers in diameter. The height of the crystal they can vary from nothing to microns. The whole motor is actually smaller than the smallest linear biomolecular motor (kinesin), hence the "smallest motor" claim.

      Thus the fundamental technology is atoms, and is nanoscale. Furthermore, to call this technology "not nanotechnology" is absurd! This is the technique that may enable atomic construction. The ability to move individual atoms around very, very quickly and in an extremely controlled manner is essential to "Drexler's vision", as you call it. Imagine an array of carbon nanotubes, each with a resevior of a different metal at one end, which can be scanned across a surface like an inkjet printer head, depositing atoms on a surface. You would then have "atomic nanotechnology", which is what Feynman's original vision actually was.
      • Your post is very informative, but I don't quite understand why you think the Zettl motor qualifies as molecular nanotechnology. Depositing a monolayer at a time onto a crystal is nothing new. People have been doing that for ages.

        Furthermore, to call this technology "not nanotechnology" is absurd!
        You're misquoting me. I didn't say it wasn't nanotechnology, I said it wasn't molecular nanotechnology: "The Berkeley group's motor, for instance, is clearly on a scale (hundreds of nm) that is not molecular nan

        • I didn't mean to misquote you, sorry.

          In nanotechnology, the question of what is a molecule is a hard one. Is a carbon nanotube, which is 1nm in diameter, but perhaps many micometers long, a molecule? It is smaller, in weight, than many proteins, which are undoubtably molecules. Are 2 covalently bonded gold atoms a molecule? 3? 12? 100? Where is the cutoff point? Certainly, we should include things like DNA polymerase and kinesin... things for which motion and interactions on the atomic scale are impo
  • Does anybody else feel a bit overwhelmed (in a good way!) by the ever increasing pace of technology? Its not many generations that get to see the works of their science fiction books spring into existence and become an every day part of our lives.

    • Its not many generations that get to see the works of their science fiction books spring into existence and become an every day part of our lives.

      Probably because very very few generations have actually HAD science fiction books...

      That said, the pace is certainly picking up and while it's hard to tell from an insider's point of view, the pace almost seems geometric. Which makes sense really - each new generation of technology helps up build the next one even faster than the previous tools.

      The quest
      • The question is will we get to the point where our brains just can't take it? Will we have to pass such things onto computers, or find a way to enhance our brains to cope with it?

        See, I take the opposite view on this. I feel that technology is actually making life a lot easier for our brains. Perhaps not for all of us, but take an average person. You can effectively run much of your life on autopilot. Driving a car, following mindless rules, technology providing cues and such. Really, many of the things t
        • I agree that technology is in many ways making it easier for our brains, but IMO that's completely overwhelmed by the sheer rate that knowledge is accumulating.

          Certainly even an average science student today has a wider knowledge of things than a well respected scientist a few generations ago. Go back a few more generations and that student would be on par with the greatest scientific minds in the world as far as knowledge goes.

          A mere few hundred years ago it was possible for one person to hold the comple
        • While I agree with you in general, in specific I have to take exception: driving a car is not something you can do on autopilot.

          We have too many drunk-driving accidents as refutation.

          Once we have autonomous cars, then I agree, it will be auto-pilot (and I can start making the same use of my time as I would if I took the "finishing-the-project-stealing" train).

      • Depends on your definition of science fiction (and I suppose book).
        Verne is generally considered science fiction.
        Shakespear wrote something about a balloon trip to the moon IIRC.
        Leonardo had some ideas that were science fiction-esq for his time, though I don't recall that he ever wrote stories about them, just diagrams.
        Not long in the scale of things I suppose, but still a few hundred years at any rate.

        Mycroft
    • The late 1800's and early 1900's saw much more radical change than we experience. Electricity, Sanitation, Railroads, Cars, Airplanes, Telephones, Iron Steam Ships, Antibiotics, Physics and Math Revolutions (Relativity, QM), etc. Life when from Medivial to Modern in something like 50 years.

      What we experience is trivial in comparison.

      Of course if those cheap nano-assemblers appear than I will take it all back.
      • The late 1800's and early 1900's saw much more radical change than we experience.

        Well, I guess from that perspective, we should consider the change that came with the printing press. That event (where knowledge could spread more instantaneously and more widely than ever before) is actually more akin to what we're experiencing now (though the scales are stupifyingly different). My point, I guess, is that changes during the industrial revolution basically introduced speed and reliability to more or less fa
      • Re:I Disagree (Score:3, Insightful)

        by Anonymous Coward
        You're talking about over 100 years' worth of innovations though - railways were invented before the Victorian age even started, and antibiotics weren't used until the 1930s.

        Look around you and ask yourself if what you see was available in 1905. I'm sitting in front of a Universal Machine capable of working out any calculable problem. I can talk to anyone and everyone I know without leaving my chair. I could look at the entire human genome and check to see if I share any sections with a chicken. I can list
        • None the less, if you think about someone who was born in say, 1860, and died in 1940, and think of the change they experienced, and then go say, 1920 to 2000, you will see what I mean.

          The former one went from a Dickonson society with short life expectations, lack of hygene, etc, to the 50's, with very many discontinuous radical changes.

          The latter one saw what was essentially continuous incremental change.
          • This is a different kind of change, it's social change you are talking about. Further improvements today are prevented for ideological reasons. It is already feasible to have a communist (in a good sense) society, where crime is low, where most people are well-educated and well-cultured, where people are healthy and noone is poor, where boring and dangerous work is done by machines. Of course, then you wouldn't be able to buy a 300000$ house, get a 70000$ car and other stuff like that, so the "elite" is qui
  • by Artifakt ( 700173 ) on Sunday April 10, 2005 @04:48PM (#12195899)
    At first, I thought the DNA assembly-Sierpinski Triangle story was particularly interesting, as a link between real world information storage and the usually unworldly area of fractal geometry. On following the story, it turns out that the error rate is simply enormous (1 to 10%). DNA, in normal use, works about a billion times more reliably than it does here.
    You could probably coax DNA to assemble into face centered cubic crystals with a much lower error rate than that. Hell, you might be able to get little figures of Snoopy and Garfield more reliably than these Sierpinski Triangles. This is like proving you could workably rebuild the Golden Gate bridge from Mayonaise and save the tax-payers a fortune, for sufficiently low values of "workable","fortune", and probably "Mayo".
    • by xEndymionx ( 757963 ) on Sunday April 10, 2005 @05:26PM (#12196059)
      the error rate is actually rather low, the high number reported comes from error propagation. if you get a single site error, the next generation of cells below it will be computed using that error, and will thus also be erroneous. the actual number of genuine errors is rather small. winfree also has done work in error-correcting self assembly of wang tiles (which is what this really is). the key point to his generating the sierpinski gasket is that it proves that one can computer elemetary cellular automata with this dna blocks, and that includes eca rule 110, which has been proven to be universal by matthew cook. dr. winfree gave a talk about all these findings early last semester at my university.
    • This particular pattern is just a proof of concept. What it implies is that you can potentially program how the crystal will grow.

      Try to imagine something more useful. Like a growing memory chip, or cpu.
    • I didn't RTFA, but I've read many of Eric's papers and met/conversed with him several times. I don't see what the problem is with the error rate. Yes it is high, but my understanding is that what Eric is trying to do is harness the massively parallel nature of DNA based computation, remember Avagadro's number is a very big number, and not develop a novel kind of information storage. Also, since no one has done this yet, he obviously has to start with simple problems, eg the Sierpinski experiment and the
      • That's sort of my point.
        Yes this is useful science - it's a proof in practice of the potential feasability of using DNA for some forms of parallel computation, and I'm sorry if it seemed like I was rejecting that accomplishment. That's a pretty decent thing to have done, even to this stage.
        Where I see a problem is there's no natural mapping between using Sierpinski Triangles as a form of binary decision tree, and their other aspect as an example fractal entity (and of course a real world construct can'
  • by screwballicus ( 313964 ) on Sunday April 10, 2005 @05:59PM (#12196218)
    It is I suppose some kind of audio-vibratory-physio-molecular transport device?
  • Prior Nanoart (Score:3, Interesting)

    by Doc Ruby ( 173196 ) on Sunday April 10, 2005 @06:54PM (#12196473) Homepage Journal
    Ned Seeman's NYU lab produced algorithmic self-assembling Wang tiles for cumulative XOR computation a couple of years ago [nyu.edu]. The application was inspired by suggestions by Winfree that their then-current system, could accomplish the computation. And it has. Glad to see Winfree continuing to explore this cutting edge.
  • ...but can it run Linux??
  • Very cool (Score:2, Interesting)

    by RacerZero ( 848545 )

    Guess I should have staid in microbiology instead of going to Art School. I did these Sierpinski sieve based pieces [marckerr.com] way back then.

    Glad to see someone doing something a little more significant with the idea.

  • single-protein wet biotransistor... algorithmic self-assembly of DNA Sierpinski triangles...

    brain.... ...hurts...

  • I believe this level of technology will lead to such devices as the Supository phone. A small 'contact pill' like devices that when lodged in the anal cavity will permanently lock itself to your tail bone and use your bone network to transmit sound to your ear drumbs and pick up your voice from the same. To dial up a number you would simply call out the command into thin air. YOu would hear the computer ask you if you wanted to dial this person or what not. YOU could adjust the settings to vibrate for q
  • First post!! I work in a nanotechnology department in England, studying for a PhD. Im pleased to tell you I once used or SEM to draw a tiny micormeter sized phallus on a wafer, complete with testicles and hair. Ill dig out the picture if I can find it.

Do you suffer painful hallucination? -- Don Juan, cited by Carlos Casteneda

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