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Science Communication
The nomadic state

Intellectual nomadism and its virtues

Scientific discovery can thrive on lack of familiarity. Often, an outsider to a field will rejuvenate it and render it fertile. 1 Cross-disciplinary research is fecund. But how to encourage it? How does one go across scientific boundaries? Where obtain the "road maps" and the guides for venturing into unknown territories?

An obvious answer is multidisciplinary teams, small enough that conversation will ensue and that a "trading zone" 2 will start to exist. One ought to encourage also (bureaucracies running science as a district administration by their very existence discourage it) a spirit of intellectual nomadism. Nomadic tribes, nomadic people, nomadic nations have enriched history. Remember some of their epics: the Jewish diaspora; the Westward move from the Gobi Desert to Central Europe and to Scandinavia of Magyars and Finns; the Turkish migration from the shores of the Pacific to present-day Turkey; the tribulations of the Mongols from Central Asia to set-up empires in India and China; the Indo-European migration into Western Europe, the Gypsies embodying its lingering trace; closer to us, in the nineteenth century, the Western expansion of the United States. Such moves of populations are emblematic of a free-roving spirit of enquiry across disciplinary boundaries. A living example is Paul C. Lauterbur, a pioneer in many areas within nuclear magnetic resonance (nmr). Two of those areas he explored and put on the map almost single-handedly are carbon-13 nmr and magnetic resonance imaging (mri). His motto, borrowed from the US military during the Vietnam War, is "search and destroy," with the meaning of forays into unknown territory for "quick and dirty" (another American phrase) sizing-up the riches.

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Michelet vulgarisateur

Résumé

Pourquoi Pasteur s'est-il livré à l'attaque publique de Michelet? La réponse à cette question se trouve du côté de la jalousie d'auteur: Pasteur ambitionne la gloire littéraire, celle du génial vulgarisateur que Michelet est devenu.

L'a-t-il fait, comme Pasteur l'insinue, au détriment de l'exactitude scientifique? S'il est permis de généraliser à partir d'une citation de L'Insecte, il semblerait plutôt que Michelet présente une information tout-à-fait fiable; davantage, qu'il fut un précurseur, annonçant et anticipant certaines des percées de la science du XXe siècle.

Mais l'exposé, loin de verser dans l'hagiographie, nous montrera aussi un autre aspect de Michelet vulgarisateur, celui de l'habile plagiaire. L'analyse d'une page célèbre de La Mer nous le fera voir dans cet autre rôle.

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The say of things

by Roald Hoffmann and Pierre Laszlo

In search of a chemical conversation we are on a farm in Uniow, a little Ukrainian village in Austro-Hungarian Galicia, just before the onset of World War I. In the farm yard we see a big, steaming lead-lined iron pot. The men have mixed some potash in it (no, not the pure chemical with composition KOH from a chemical supply company, but the real ash from burning good poplar) and quicklime, to a thickness that an egg ÿ plenty of eggs here, judging from the roaming chickens ÿ floats on it.

Elsewhere in the yard, women are straining kitchen grease, suet, pig bones, rancid butter, the poor parts skimmed off the goose fat (the best of which had been set to cool, cracklings and all). This mix doesn’t smell good; they would rather toss the kitchen leavings and bones into the great iron pot, but the fat must be free of meat, bones, and solids for the process to work.

They are making soap. Not that we had to go that far, near where one of us was born, for soap was prepared in this way on farms since medieval times well into this century. Fat was boiled up with lye (what the potash and quicklime made). The reaction was slow ÿ days of heating and stirring until the lye was used up, and a chicken feather would no longer dissolve in the brew. One learned not to get the lye on one's hands. The product of a simple chemical reaction was then left in the sun for a week, stirred until a paste formed. Then it was shaped into blocks and set out on wood to dry.

And inside the steaming pot, deep inside, where the fat and the lye are reacting? There is the conversation we are after, a hellishly animated molecular conversation. The lye that formed was an alkaline mixture of KOH, Ca(OH)2 and NaOH. In the vat one had hydroxide (OH-) ions, and K+ , Ca2+ , Na+ all surrounded in dynamic array and disarray by water molecules. Contaminants aside, the fat molecules are compounds called esters, in which an organic base, glycerol, combines with three long-chain hydrocarbon chains. A typical one is stearate:

If we just call this ion Rÿ, then the formula for a fat is roughly

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