Archive for April, 2010

How science is supposed to work

April 28, 2010

Doug’s blog Nanoscale Views is one that I enjoy reading. Here is his latest post on how science is supposed to work:

There’s an old quote from Isaac Asimov that is very true:  “The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny…’.”  In my group, we recently had an experience that supports this, and it highlights what I think is some of the most fun you can have as an experimental scientist:  trying to use the tools at your disposal to learn as much as you can about what’s behind some unexpected and surprising phenomenon.

It’s been science-as-puzzle-solving, trying to figure out what could be going on here.  We came up with many possible explanations, and tried to come up with ways to test the possibilities, eliminating the ones that didn’t fit.  … it’s a good example of how sometimes systems that you think are dull can surprise you, and how science is supposed to work.

A nice one!

When industries in your field of specialisation grow too big

April 27, 2010

To be studied at the University scale, what happens to research? Here is Matt Welsh on CS and industry:

‘ve been doing a lot of thinking lately about the role of academic computer science research vis-à-vis the state of the art in industry. When I was in grad school at Berkeley, we were building “big systems” — the 200+ node cluster that I did all my research on was on the rough order of the size of sites like Inktomi and Google at the time. Since then, industry has scaled up by orders of magnitude, leaving academics in the dust. These days it’s not clear that it makes sense for a university research group to work on systems problems that try to approximate industry: not only do we not have the resources, we simply have no idea what the real problems are at that scale. My friend and colleague Steve Gribble told me that after doing a sabbatical at Google, he decided that there’s no way a university group could compete with what they’re doing.

A must-read post.

By the way, if you do not have big enough industries in your specialisation so that you can be aware of industrially important issues to address, that is also a problem. This can, of course, lead to the question as to how big the industries in your area of specialisation be for optimal interactions!

On wetting and on controlling shape memory

April 27, 2010

Via Sami Mira’s viewpoint, I ended up on this paper by Smith and Bertola in PRL:

When a droplet of water impacts a hydrophobic surface, the drop is often observed to bounce. However, for about 10 years it has been known that the addition of very small quantities (∼100  ppm) of a flexible polymer such as poly-(ethylene oxide) can completely prevent rebound. This effect has for some time been explained in terms of the stretching of polymer chains by a velocity gradient in the fluid, resulting in a transient increase in the so-called “extensional viscosity.” Here we show, by measuring the fluid velocity inside the impacting drop, that the extensional viscosity plays no role in the antirebound phenomenon. Using fluorescently labeled λ DNA we demonstrate that the observed effect is due to the stretching of polymer molecules as the droplet edge sweeps the substrate, retarding the movement of the receding contact line.

Here is a viewpoint by Antoni Planes on controlling Shape Memory:

The essence of turning physics into technology relies on one verb: control. Whether it is controlling electricity with magnetism, magnetism with electricity, or controlling spins, currents, or fields, control is the necessary ingredient. Through the shape memory effect, it now becomes possible to control mechanical effects with electromagnetic stimuli.

At present, it is known that almost any Ni-Mn-based Heusler alloy will show a martensitic transition at an appropriate off-stoichiometric composition. In addition, these materials show other interesting functional properties such as magnetoresistance or magnetocaloric effects. The complex behavior displayed by these materials is, to a large extent, a consequence of the strong coupling between magnetism and structure that arises from the martensitic transition as the sample is cooled. Now, in a paper published in Physical Review Letters, Mao Ye and Akio Kimura at Hiroshima University, together with collaborators at Tohoku University, the National Institute for Materials Science, and Tohoku Gakuin University, all in Japan, study the case of Ni2Mn1+xSn1-x alloys to elucidate the role of excess Mn ions in driving the martensitic transition.

Have fun!

HowTo: avoid bad writing

April 25, 2010

Rachel Toor dissects bad writing for you (link via Brayden at Orgtheory):

By writing prose that is nearly unintelligible not just to the general public, but also to graduate students and fellow academics in your discipline, you are not doing the work of advancing knowledge. And, honestly, you don’t really sound smart. I understand that there are ideas that are so difficult that their expression must be complex and dense. But I can tell you, after years of rejecting manuscripts submitted to university presses, most people’s ideas aren’t that brilliant.

Call me simple-minded, call me anti-intellectual, but I believe that most poor scholarly writing is a result of bad habits, of learning tricks of the academic trade as a way to try to fit in. And it’s a result of lazy thinking. Most of us know that we may not be writing as well as we could, or should. Many academics have told me that they suspect they are bad writers but don’t know how to get better. They are often desperate for help. I tell them to reread Strunk and White, and to take a look at “Politics and the English Language.” Yeah, yeah, they say, and get buried working toward the next submission deadline, prepping for the next class.

But this is not to be taken lightly.

I’m going to provide a gloss on Orwell’s essay, in the hope that it will encourage a few wannabe-better writers to read it themselves. (You can find the original in seven seconds of Googling.)

To save those seven seconds for you (and, also because I really like), here is Orwell’s (must-read) piece.

The loss from the north and from the south

April 25, 2010

Githa Hariharan’s tributes to DKP and Gangubai Hangal in The Telegraph is a must-read:

The voices of two grand old women fell silent last year. With the passing of D.K. Pattammal and Gangubai Hangal in 2009, we lost two of our most important performers, one from each of the two streams of classical Indian music. They had quite a bit in common, these extraordinary women. Both were lauded as brilliant performers. But more important, they were hailed as musicians who engaged deeply with the technical nuances as well as the spirit of classical music.

Both said they listened to different types of music. But they were committed women. Their commitment anchored them firmly in their respective streams, with a steadfast loyalty to their schools of music and to their gurus.

Neither woman was viewed as particularly feminine, either in terms of appearance or voice. Both had unusually strong and deep voices, with Gangubai’s voice often being described as masculine. (Typically, this did not bother Gangubai — it did not “hurt” her, she said, because “as long as sur and bhaav are right, nothing else matters”.) The integrity the two radiated — the refusal to compromise with principle — was as powerful as their voices.

Take a look!

Athletics and their brains

April 25, 2010

The brain begins by setting a goal—pick up the fork, say, or deliver the tennis serve—and calculates the best course of action to reach it. As the brain starts issuing commands, it also begins to make predictions about what sort of sensations should come back from the body if it achieves the goal. If those predictions don’t match the actual sensations, the brain then revises its plan to reduce error. Shadmehr and Krakauer’s work demonstrates that the brain does not merely issue rigid commands; it also continually updates its solution to the problem of how to move the body. Athletes may perform better than the rest of us because their brains can find better solutions than ours do.To understand how athletes arrive at these better solutions, other neuroscientists have run experiments in which athletes and nonathletes perform the same task. This past January Claudio Del Percio of Sapienza University in Rome and his colleagues reported the results of a study in which they measured the brain waves of karate champions and ordinary people, at rest with their eyes closed, and compared them. The athletes, it turned out, emitted stronger alpha waves, which indicate a restful state. This finding suggests that an athlete’s brain is like a race car idling in neutral, ready to spring into action.

Del Percio’s team has also measured brain waves of athletes and nonathletes in action. In one experiment the researchers observed pistol shooters as they fired 120 times. In another experiment Del Percio had fencers balance on one foot. In both cases the scientists arrived at the same surprising results: The athletes’ brains were quieter, which means they devoted less brain activity to these motor tasks than nonathletes did. The reason, Del Percio argues, is that the brains of athletes are more efficient, so they produce the desired result with the help of fewer neurons. Del Percio’s research suggests that the more efficient a brain, the better job it does in sports. The scientists also found that when the pistol shooters hit their target, their brains tended to be quieter than when they missed.

Good genes may account for some of the differences in ability, but even the most genetically well-endowed prodigy clearly needs practice—lots of it—to develop the brain of an athlete. As soon as someone starts to practice a new sport, his brain begins to change, and the changes continue for years. Scientists at the University of Regensburg in Germany documented the process by scanning people as they learned how to juggle. After a week, the jugglers were already developing extra gray matter in some brain areas. Their brains continued to change for months, the scientists found.

From this piece of Carl Zimmer. Link via Swarup.

Writing in one’s own voice

April 22, 2010

Is very important and Terence Tao has more to say on the subject.

The Indian university system

April 22, 2010

Andre Beteille, in a piece in The Telegraph:

The universities cannot continue to be viable if they are set contradictory objectives. In the typical case, the Indian university is expected to produce hundreds of thousands of graduates every year, and these numbers keep rising. But it is also expected to maintain and even advance standards of teaching and research in all significant branches of learning. Those who advise the government know that these two objectives cannot be met simultaneously by the same institution or the same kind of institution, but their desire to be of service to the nation leads them to hope that they will somehow be able to square the circle.

Though Beteille is not stating it explicitly, his piece seems to argue for more and more of Indian Institutes of XXX type universities:

Perhaps the all-purpose university of the 19th and early 20th centuries has outlived its utility in the 21st century. If the university is to be viable as a centre of advanced study and research, it may have to limit the ambition that it earlier had of covering all branches of existing knowledge. At the same time, a university will scarcely deserve to be called one if it confines itself to a single subject. There is really no good reason to swing from the extremes of inclusion to the extremes of exclusion. A university can serve as an effective institution of teaching and research if it limits itself to a cluster of related subjects, and restrains its ambition for indefinite expansion.

It appears to me that we can still create universities that will be communities of learning, combining teaching and research, provided they are able to limit their scale and scope. Such universities will of course have to conduct examinations and award degrees, but the conduct of examinations and the awarding of degrees need not become their sole or even their main concern as inevitably happens in the mass universities.

Take a look!

Plastic currency notes

April 18, 2010

Thanks to an email alert from a colleague, I learnt about the essay by Prof. David Solomon titled Australia’s Plastic Banknotes: Fighting Counterfeit Currency:

Worlds first banknote printed on clear plastic film and using optically variable devices (OVDs) was issued in Australia in 1988 after twenty years of research and development. In the course of this, a great deal of technical as well as logistic issues had to be solved.

A must-read and fascinating piece! Here is the press release from Wiley.

A few interesting pieces from BMC

April 15, 2010

[1] A personal view on autism — you can either watch the video or read the edited transcript.

[2] When and whether to model — in molecular biology

[3] When it comes to scientific publishing, bigger is better?