Some must-read stuff!

Avian Grandmas

A few months back, I wrote a post titled In praise of grandparents; the post lead to some interesting discussions, where, I also wrote about how birds cope with child rearing:

As far child rearing, it is interesting to see how other species cope with the burden–in some bird species, for example, when the mother gets children, it is the elder sons who are forced to help the mother; in fact, the father will actively stop the sons from setting up their own nests! All this is explained in this rather nice article (pdf) (and in this book too, called Survival Strategies by Raghavendra Gadagkar).

However, I am afraid I was too quick to conclude that there are no avian grandparents. In a very readable post, Grrlscientist explains some recent research along these lines:

When talking about evolution, some people have wondered aloud about why grandmothers exist in human society since they clearly are no longer able to reproduce. However, these people are conveniently overlooking the fact that grandmothers perform a valuable service; they help their relatives, often their own children, raise their offspring — offspring that are genetically related to them. But curiously, grandmother helpers have not been documented to occur in birds, where most of our research into cooperative breeding systems occurs, so this makes the question even more intriguing: Why are there no avian grandmothers? Further, since cooperatively breeding birds are relatively long-lived, grandparental care should indeed be identifiable, especially if cooperatively-breeding bird societies are observed long enough.

(…)

This is the first time that grandparent helping has been documented in birds, although there are several other species where kin-directed helping behavior has been observed.

However, it is important to note that in other avian helping species, “all individuals attempt to breed independently each year and only move to helping if their nest fails. Consequently, this behavior would be very different to that of individuals that forgo independent breeding and become subordinate grandparent helpers.

A very interesting piece!

Oxytocin and childbirth

A couple of years ago, if I had seen a blog post on oxytocin and childbirth, I would have moved on without paying close attention; however, all the child care classes that we attended as well as my staying with my wife during our daughter’s birth has made me more aware; so, it is with great interest that I read Coturnix’s post on the issue — true, there seems to be more questions than explanations — but that is what makes is all the more interesting. Take a look!

A researcher’s nightmare(s)

It had happened to almost all the researchers I know; it happened to me recently when, one of my collaborators, who was trying to use my code reported that he is not able to reproduce some of the results that I report in my thesis; the nightmare lasted a couple of days before we could sort everything out, and thankfully, my results were indeed reproducible.

Highly Allochthonous writes about a similar horrifying experience that he went through recently; and, again, thankfully, it turns out that what he thought to be the mistake, actually wasn’t:

It was at about this point that an entire PhD’s worth of stress hormones decided to dump themselves into my bloodstream. It looked like all the cool and exciting conclusions from my PhD research were built on an exceedingly unsafe foundation. Also, if I was honest with myself, such a glaring mistake galloped far beyond the unfortunate, deep into the realm of the toweringly incompetent. Writing and publishing the necessary corrections and retractions would be equivalent to standing up in a room packed with everyone who might ever hire me and yelling “Hey! I’m a dumbass!”

It was a good job, then, that I turned out to be mistaken - although it took me until Monday to realise it. My salvation lay in the fact that samples were not placed in my old magnetometer in the ‘right’ orientation: what the machine measured as the x-axis was in fact the z-axis of the sample. This substitution meant that when the correction software rotated what it thought was the x-axis, it was actually rotating the z-axis of the sample, which meant that I was supplying the right direction and everything had ended up in the appropriate reference frame. ‘Phew’ is an understatement.

It is important to note though, that it is not always that such stories have such a happy ending. On another occasion, a week before my submitting an important document, I found a bug in my code. As Chris Rowan mentions, that is the time I realised how much of research reporting is based on trust. I am happy to say that I had enough courage to tell my adviser (who was more cool in that, instead of getting upset about my carelessness, he said “Guru, it is better that we noticed it before the referees did; throw away all the tainted results, run the code once more and let us see”). Fortunately, the changes in the results were more quantitative than qualitative. Again, for me too, “Phew” was an understatement.

Apart from these, there is another nightmare that some of us face–especially in the early stages of research–when you open a journal and see a paper which ostensibly solves the exact problem that you are trying to solve. But, as one of my experiences colleagues pointed out to me when I faced one such situation long ago, it is never that two groups would independently solve the same problem, using same techniques and arrive at identical results. So, most of the times, something of your efforts can be salvaged. But, it still is a nightmare when it happens.

A strongly recommended book

Recently, Jonah Lehrer recommended Body has a mind of its own (as we noted here); it is Grrlscientist’s turn now:

As a biologist who reads both widely and deeply about a number of scientific topics, it is very rare when I read a popular book that adds depth and nuance to my understanding of a biological phenomenon, but The Body Has a Mind of Its Own By Sandra Blakeslee and Matthew Blakeslee (NYC: Random House; 2007) is that book. This quiet but well-written book explores the interconnection between the environment, the body and the brain; discusses that the body is more just than a container for the brain and a vehicle that moves it around; and reveals how the brain depends upon sensory feedback from the environment in order to develop properly.

Looks like a must-read book. Take a look!

Happy reading!

Why writers are like otters

“Writers are otters,” states Neil Gaiman, firmly. (…)
“Otters are not trainable,” he explains. “Dogs are trainable - if you want them to sit you train them and give them rewards and they sit each time. But otters… if they do something cool and you give them a fish, the next time they’ll do something even cooler. Or they’ll try to do something completely different. I think that most writers - or at least a lot of us - are otters.”

From this Guardian piece; via Jenny.

Thursday morning links

• Tara Smith at Aetiology reviews Twelve diseases that changed our world and finds that though its bias towards Western history and civilization is a limitation, it is a book worth reading nevertheless;
• Inside Higher Ed informs that Utah OpencourseWare Alliance, a statewide initiative, goes online today; and,
• Vaughan at Mind Hacks informs about the online availability of Daniel Kahneman’s masterclass.

Few more links!

1. With grad student advice, can applying for faculty jobs be far behind? Julianne at Cosmic Variance offers some (unsolicited, but timely for some of us) advice;
2. Do birds “see” magnetic fields? Clifford at Asymptotia points to some online resources (and, is on the lookout for more info);
3. Tyler Cowen recommends a couple of very good books; and,
4. Henry at Crooked Timber on some free software for academics (as well as on their guilty pleasures).

Take a look!

Mukul Kesavan on blogging

The average blog tends to be a person’s online journal, an archive of his writing and an inventory of his interests all rolled into one. Narcissism is built into the form. So is coyness. The blogger must do two things at once: cultivate his readers while being his interesting self. All writers have to do this in lesser or greater degree, but nowhere is the lag between writing, reception and response so small, and in no other medium is it so continuous. How to draw attention to your cleverness while being disinterestedly intelligent about matters of general interest becomes the daily challenge for the diligent blogger. It is an impossible tight-rope to walk for any length of time and it invariably ends in unstable combinations of knowingness and modesty or self-congratulation and discretion, whereupon an awful coyness is born.

If the weaknesses of blogging spring from individual self-love, its strengths are collective. Bloggers are the conscience of the internet and, increasingly, of the mainstream media. Any error of fact, however small, made by me on my cricket blog is snouted up in a matter of hours, if not sooner. Bloggers learn to get their facts right because their peers and their readers are so unforgiving. Newspaper columnists used to get away with much more than they do now because there’s an army of unpaid fact-checkers cruising online who see it as their life’s work to ‘fisk’ sloppy opinion or reportage.

Blogging at its best is intelligent conversation between the blogger and his readers. Collectively, blogging serves an important editorial purpose. But, on the whole, blogging produces derivative and self-indulgent writing. It’s ironic that ‘fisking’, the blogger’s verb for aggressive or hostile fact-checking, is named after Robert Fisk, Britain’s most distinguished foreign correspondent, who has lived in and reported from the Middle East for the past quarter of a century. His trenchant critique of Anglo-American foreign policy has made him a byword for bias amongst right-wing bloggers. That a great journalist who has survived danger and risked death to live in the region he reports from, whose reportage has made him the doyen of Middle-Eastern reporting, should become the blogosphere’s measure of unreliability, tells us something about the frictionless sterility of the blogger’s online world.

From the latest Telegraph piece of Mukul Kesavan; and, more interestingly, from the piece, I found that Kesavan does indeed blog about cricket; Cf. with Kesavan’s one of the earlier columns and the responses to it.

A couple of links!

1. Sean’s Unsolicited (but wonderful) advice on how to be a good grad student (Perhaps, it is a little late for some of us; but then, it is too good a piece to be passed over); and,
2. Oliver Sacks’ iPod playlist (No, he does not have one; it is the list of songs he would have in his iPod, if he happens to own one).

HowTo: write a better resume

A (programmer specific) list of ten tips from Stevey’s blog rants:

1. Nobody cares about you;
2. Use plain text;
3. Check, please;
4. Avoid weasel words;
5. Avoid wank words;
6. Don’t be a certified loser;
7. Don’t say “expert” unless you really mean it;
8. Don’t tip you hand;
9. Don’t bore us to death; and,
10. Don’t be a lying scumbag.

Take a look!

Multiferroics: Progress and prospects

Today, I heard Prof. Nicola Spaldin of Materials Department, University of California, Santa Barbara on Progress and prospects in multiferroics. I learnt quite a few concepts and ideas today; here is the summary based on my notes. As usual, if I owe the clarity of ideas and presentation to Prof. Spaldin, any mistakes you may find are most probably mine.

Multiferroic materials are, as this wiki page notes, materials with two or more ferroic properties, namely, ferromagnetic, ferroelectric, and ferroelastic properties. Prof. Spaldin began the talk by noting that her interest in multiferroic materials that are ferromagnetic and ferroelectric at the same time is just one example of a more general class of materials known under the general rubric of contra-indicated multifunctional materials.

What is contra-indication? Consider a material which is transparent — this optical property is an indication that there is a band gap in the electronic structure of the material. On the other hand, in electrically conducting materials, there is an overlap of the valence and conduction bands (and, hence, no band gap). Thus, transparent conductors are by definition contra-indicated; thus, contra-indicated materials are those with pairs of functionalities that can a priori be expected not to exist together in a given material.

So, why is a multiferroic material that is both ferromagnetic and ferroelectric contra-indicated? Apparently, the contra-indication is chemical — magnetism (more specifically, in perovskites with transition metal ions) is dependent on localized transition metal d-electrons, while, atoms with such localised d-electrons don’t off-center in their crystal structure to form ferroelectrics. Thus, the requirement of filled d-orbitals for magnetism (apparently, also known as Stoner instability in the physics literature — I do not know exactly what that is — I might do a post about it sometime in future), is not compatible with the second-order Jahn-Teller effect which requires empty d-orbitals for ferroelectricity — since, apparently, in the Perovskite structure, the electron transfer is from the p-electrons of Oxygen to the empty d-orbitals of the cation when it shifts away from the centre of the unit cell — I understand that the technical name for such an electron transfer in the chemical literature is ligand field stabilization.

So, what is the way out? There seem to be several options. Prof. Spaldin concentrated on one strategy: since in a typical perovskite structure, there are two metal ions, leaving the metal atom in the centre of the Oxygen octahedron untouched (so that the material can still be ferroelectric via the usual mechanism), by aligning the spins of the electrons in the other metal atom, a material can be tricked to be both ferroelectric and ferromagnetic at the same time.

Using some approximate first principal density functional calculations, apparently, it has been calculated that BiMnO3, (since the Bi³⁺ are “stereochemically active lone pairs” as in Ammonia, which gives the non-planar shape to the molecule), may be expected to be ferroelectric (while Mn will give rise to ferromagnetism). However, thin films of this material were reported to be both ferromagnetic and ferroelectric, albeit with a very weak polarization (as if the material is not ferroelectric, but anti-ferroelectric). As an aside, later full-blown first principle calculations have shown that the material will indeed be perfect anti-ferroelectric with zero polarization (Moral of the story: sometimes it pays to do approximate calculations). Prof. Spaldin speculated that the experimental observation of weak polarization (while the theory predicts the material to have zero polarization) could be due either to epitaxial strains or defects; however, the issue is still open.

Another attempt at theoretical calculation, with the same strategy in mind, on BiFeO3, resulted in very strong ferroelectricity (so much so that they might be the next generation ferroelectric materials); however, the material is antiferromagnetic. Thus, the result of the usage of this strategy seems to be a tendency for ferro+anti-ferro combination, and not ferro+ferro combination.

Prof Spaldin also spoke about the attempts to couple magnetic and electric fields using magnetoelectric tensors in (a) polar materials that are magnetic, and (b) heterostructures of SrRuO3/SrTiO3.

As can be seen, multiferroics seems to be a field full of challenging and interesting problems, where theory and experiments drive each other (which was one of the undercurrents in Prof. Spaldin’s talk — the need for good theoretical calculations, and the importance of understanding the nuances associated with the theoretical methods and approximations so that the reliability of a given prediction can be assessed).

For those of you who are interested in learning more about this area, I can do no better than to refer to Prof. Spaldin’s publications page (which refers to several nice review articles). I have also listed and linked some of the papers that Prof. Spaldin referred to in her talk.

Happy reading!

Bibliography:

1. The renaissance of magnetoelectric multiferroics, Nicola A Spaldin and Manfred Fiebig, Science 15, July 2005, Vol. 309, No. 5733, pp. 391-392.
2. First principles investigation of ferromagnetism and ferroelectricity in bismuth manganite, Nicola A Hill and Karin M Rabe, Phys Rev B 59, 1999, pp. 8759-8769.
3. Epitaxial growth and properties of metastable BiMnO3 thin films, A F Moreira dos Santos et al, Applied Physics Letters, January 5, 2004, Vol. 84, Issue 1, pp. 91-93.
4. Evidence for the likely occurrence of magnetoferroelectricity in the simple perovskite, BiMnO3, A Moreira dos Santos et al, Solid State Communications, Vol. 122, Issues 1-2, April 2002, pp. 49-52.
5. Anti-polarity in ideal BiMnO3, Pio Baettig, Ram Seshadri, and Nicola A Spaldin, J Amer Chem Soc, Vol. 129 (32), 2007, pp. 9854-9855.
6. Epitaxial BiFeO3 multiferroic thin film heterostructures, J Wang et al, Science 14 March 2003, Vol. 299, No. 5613, pp. 1719-1722.
7. Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite, Claude Ederer and Nicola A Spaldin, Phys Rev B, 71, 060401 (R), 2005, 4 pages.
8. Magnetic control of ferroelectric polarization, Kimura et al, Nature, 426, 6 November 2003, pp. 55-58.
9. Revival of the magnetoelectric effect (Topical Review), Manfred Fiebig, 2005, J Phys D: Appl Phys, 38, R123-R152.

HowTo: become a MacArthur genius

Rule No. 2: Be a professor. Specifically, be a professor at Harvard or Stanford, where they hand out MacArthurs like candy. If you’re a humanities professor, choose Harvard (which has 35 MacArthurs) or University of California, Berkeley (which has 23). Hard scientists should land a job at Stanford (24) or Princeton (20). Physicists at one of those two universities seem to win MacArthurs more easily than tenure. In a pinch, University of Chicago, University of Michigan, Columbia, and New York University are acceptable backups, but avoid Yale! It’s got only six geniuses. You’d be better off with Bard College, whose tiny faculty has won four MacArthurs. (As Harvard grads have always suspected, Yale is approximately one-sixth as good as Harvard.)

But it’s not enough to be a professor. You also must choose the right specialty. Ancient civilizations win MacArthurs. Revisionist scholars of classical Greece do well, and MacArthur has identified not one, but two geniuses who decipher ancient Mayan glyphs and a third who deciphers ancient Andean knotted mnemonic devices (whatever they may be). Literature, philosophy, and history all win plenty of MacArthurs. Economics is unpromising, unless you study something odd. 2000 winner Matthew Rabin, for example, analyzes the economic implications of procrastination. Physics, math, and computer science are beloved of MacArthur. Chemistry is a lost cause. Environmentalism is a sure winner. Biologists should study evolution, dinosaurs, or primates, and little else.

There are six more rules along similar lines at this Slate article. Take a look!

Feeling God-like at the microscope

My own affair with Nano began with my doctoral studies at the University of Cambridge in 1962. It was an awesome experience to look at atoms with the field-ion microscope and feel God-like in evaporating tungsten atoms at liquid nitrogen temperature. This microscope predates the Feynman lecture and not many may know that its invention is due to the collaboration between Erwin Mueller and Kanwar Bahadur, who were the first to see specimens with atomic resolution in 1956.

That is Nomad Metallurgist (alias Prof. S Ranganathan aka SR aka Rangu) talking about nanotechnology.

It is not just technology, metallurgy, and microscopes that are discussed in the blog. Here is another post on his visit to Syria which quotes from an article about Syria, for example:

In certain quarters, Syrian lingerie is famous. You may not think so, but the fact is that you may be wearing it and never know. There are Syrian exporters who employ people to cut the “Made in Syria” labels out of frilly knickers and lacy bras, and replace them with ones that say “Made in Italy” prior to exporting them. A friend of mine in Damascus does precisely this job. But what is the reason for Syria’s infiltration of so many of the world’s underwear cupboards? Why Syria, of all places?
A wander around the capital Damascus gives no clues at first. Syrian culture is relatively conservative and this is reflected in what people wear on the streets. But if you know what you’re looking for, you’ll gradually start to spot it: a window of lace-up basques here, a display of fishnets there, and over there—an eyeful of bras and boas that would put the Playboy Mansion to shame. A lot of local men have a taste for such things because they’re “like children,” posits the manager of the upper-end Charme lingerie store. “They get bored easily so a girl must have many outfits.” In fact, she needs up to 30 lingerie sets for her trousseau, says Malu Halasa, co-editor of the forthcoming book The Secret Life of Syrian Lingerie. That demand helps to explain the prolific production of underwear in Syria, and its manufacturing expertise. On the supply side, Damascus’ prime position on the Silk Road has flooded the city with silks and satins since time immemorial.

Certainly a blog for your bookmarks/feedcatchers. Take a look!

Hat Tip: Abi