Teaching and research: the complementarity of

The most significant aspect of Mr. Feldon’s findings, says Mr. Connolly, is that they are based on data that track the development of actual research skills instead of those that are self-reported. “They’re looking at demonstrated competency,” he says. “It gets away from these assumptions that teaching is inimical to research. In fact, they’re complementary.”

Mr. Feldon cites two reasons that teaching seems to improve research skills. The first is that a graduate student who teaches, for example, 20 undergraduates how to develop a laboratory study ends up practicing those same skills him or herself. “It’s a straight practice effect,” he says. “You’re getting more opportunities in more situations.”

The second reason is that people who have to explain to someone else how to carry out a task are quicker to develop their own abilities to do that same task.

Teaching’s benefit to research depends on a certain kind of educational experience, Mr. Feldon continues. The educational experience for both instructor and student must involve what he calls “active inquiry,” the investigation of open-ended questions, in which students must figure out which areas deserve exploration and what data to collect.

From CHE; via Abi.

Environmental research: the social and the technical

Today I heard Prof. Sharachchandra Lele on Interdisciplinarity in environmental research: How the social is intertwined with the Technical (pdf).

Here is my three line summary of the talk. Environmental phenomena are caused by humans; and they affect human welfare. So, inherently, there are value judgements in discussions, which are hidden, and what is worse, refused to be acknowledged. Further, different approaches (political ecology, economics, conservation biologist, …) lead to different solutions — because the end goal is different for each.

Prof. Lele also made a reference to a paper by Max-Neef called Foundations of transdisciplinarity, which is available here (pdf); I think I should read it some time.

A very though provoking lecture, all in all.

The curious case of the coffee ring

Or the microscopic tetris that molecules play — a must read of the day!

Nagel’s befuddlement, which he shared with his colleagues, could be stated this way: Why does all the material suspended in a drop of coffee end up at the edge when the drop evaporates, considering that it started out dispersed across the whole drop? The effect was common to all droplets of dispersed colloidal objects, including milk, blood, ink, and paint, evaporating on a wide variety of surfaces, suggesting there should be a general explanation.

The physical picture that emerged was beautiful and simple: As the droplet dries, the liquid evaporating from the thinning outer edge, where the contact angle θ is shrinking to zero, must be replenished by liquid from the drop’s interior. This sets up a strong outward flow in the solvent, which carries most of the solute to the contact line. Pre-existing surface roughness can provide the force to pin the contact line, but the contact line further pins itself through a feedback loop between flow and patterning: the outward flow increases the deposition of solute, which serves to anchor the fluid and reinforce the outward flow.

The simplicity of this picture carries some caveats—the suppression of counterflows that are due to gradients in surface tension (Marangoni flows) is one example. However, in the years since Nagel’s observation, the coffee ring has taken on a life of its own.

On an inverse problem

Inverse problems are generally known to be hard. Here is a commentary on a couple of papers published in PRL which discusses one such problem – namely, finding a potential that gives rise to a given type of lattice. One of the papers referred to in the commentary linked above has this to say:

In general, proving that a certain configuration is the ground state of a given potential is a very hard problem. In fact, the exact nature of the ground state is not rigorously known even for simple interactions such as the Lennard-Jones potential [21]. In this Letter we have described
a direct method to design potentials for targeted self-assembly of lattices, a problem usually approached using iterative methods involving repeated relaxations of the system [2,3]. From our construction follows the somewhat counterintuitive observation that it is actually simpler to find a potential with a given configuration as a ground state than to determine the ground state(s) of a given potential.

Another thing about these papers is the use of the concept of the reciprocal space. May be I can use these papers to tell students the power of reciprocal space based techniques when I teach my mathematical methods course next semester.

 

GPS and travel

A piece in New Atlantis by Ari Schulman; via Nicholas Carr. A wonderful piece!

On the need for building instruments

Lord Kelvin is supposed to have said

“In physical science the first essential step in the direction of learning any subject is to find principles of numerical reckoning and practicable methods for measuring some quality connected with it. I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science, whatever the matter may be.”

Yesterday, Prof. M S Valiathan, who delivered the Convocation address at IIT-Bombay, discussed how, as a country, we have fallen behind in instrumentation and equipment building, and emphasised the need for developing instruments and building them for our consumption in this country. At present, apparently only 15% of our needs are met by the domestic instrument industry and the remaining 85% is imported — leading to huge losses to the exchequer as well as subsequent problems in the upkeep and maintenance of these equipments. Prof. Valiathan also referred to one of his initiatives which has resulted in the report Strategies and a road-map for development of instrumentation in India (pdf) in his talk.  At a time when workshops are getting closed in many Departments, less and less theses are produced based on home-made equipments, and, majority of engineering graduates graduate without doing too many lab courses, I think, all of us in the Engineering education sector, should pay more attention to Prof. Valiathan’s ideas and the report of INSA.