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Le regard de Jacques

Published by qdsa on April 12, 2008

“Cet oeil à la fois sagace et sans hâte qui pèse et qui rumine”, écrit Julien Gracq de Francis Ponge, dans un éloge Julien Gracq, OEuvres complètes, Bernhild Boie et Claude Dourguin, éds., vol.2, Gallimard-La Pléiade, Paris, 1995, pp. 1180-1183.: phrase à exciser, telle quelle, dans son sympathique fourbi hétéroclite, pour l’appliquer à l’ami Dubois. Jacques a mené une entreprise un peu comparable à celle de Francis Ponge, il est vrai. Là où Ponge, dans la mouvance de Jules Renard et de Paul Claudel (“Le porc”), a ouvert au poème en prose une friche, lui livrant les objets du quotidien, ces humbles fréquentations que sont le savon, l’automobile, la chèvre, le pré, Dubois s’est mis en tête d’étudier et de décrire, avec une sympathie comparable, avec une résonance ou une consonance, les formes replettes, bien nourries, du roman médical, du roman policier et de la littérature de gare. Pas seulement, certes. Proust aussi!

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Linus Pauling

Published by qdsa on April 12, 2008

His Contributions to Chemistry and Molecular Biology.

Lecture by Pierre Laszlo (Ecole polytechnique and University of Liège) given at Southern University, Ashland, February 7 1998

Let me take you on a short walk. What’s this? We ascend first a spiral staircase. It winds upward in highly regular manner, each step in the climb makes us circle a little around the axis of the structure. Thus, we come to a landing. We have reached a rather flat, but nevertheless undulating floor. We can move across it quite easily, till we reach another of the spiraling structures. The architecture I am describing is that of a building, neither man-made nor inhabitable. The building I’m telling you about is also the build-up of a protein molecule and its scale is that of atomic dimensions.

The man who made the first sighting of such an architecture for proteins, in the late 1940s, with its a-helices (the spiral structures) and with its undulating floors (the b-sheets) was Linus Pauling. His vision was, for that time, truly prophetic. And it has endured, it has been borne out by whole libraries of evidence accumulated since.

The two questions I wish to examine in this lecture are:

1. How did Pauling come to his notion of protein architecture?

2. Were all the pronouncements by this visionary genius, those about vitamin C and cancer for instance, milestones in the advancement of science?

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The Pinetree and the Molecule

Published by qdsa on April 12, 2008

The edge of the forest is close enough for a good look. Each tree is unique. The pine I am examining differs from its neighbours. This individual tree flaunts its own mortality. Some of its branches are dead, their needles have become brown and sparse. But any tree is not only constrained into immobility. Its response to the whiffs of wind is a dance. It forms a paean to the environmental pressures that have molded the evolution of this particular species.

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Juniper

Juniper

Published by qdsa on April 12, 2008

Juniperus communis L. (Conifers)

This bush, no taller than a child, is to be found on limy soils throughout the Northern hemisphere. Branches carry numerous small spiky leaves. It is a typical plant for the mediterranean garrigue (brush) landscape, at elevations ranging from 1,500 to 3,000 feet.

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The chestnut tree

The chestnut tree

Published by qdsa on April 12, 2008

Castanea dentata Cupuliferae

For millennia, mankind has domesticated this plant genus for its numerous uses, from feeding to tanning. It originated in Asia Minor: Persia, Armenia, Transcaucasia? In any case, Romans transplanted it to Western Europe. The first chestnut groves date back to when arboriculture techniques, such as pruning, budding or grafting had been mastered. During the Middle Ages, monasteries saw to preservation and development of chestnut groves. These trees are found at 1,500-2,500 ft elevations, on acidic soils (schists, granite; chestnuts hate limestone), and below about 52° N latitude, since frost destroys the flowers. It is not known when chestnut trees were introduced in North America.

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Le sel de cuisineComparaison des concentrations (en unités mM) des principaux anions et cations à l'intérieur et à l'extérieur d'une cellule-type.

Intervista a Pierre Laszlo, maggio 2001

Published by qdsa on April 11, 2008

a cura di Cristiana Spinedi

Di origine ungherese, cresciuto fra l’Algeria e la Francia, Pierre Laszlo è stato professore di Chimica all’Università di Liegi, in Belgio, dal 1979 al 1999 e alla Scuola Politecnica di Parigi dal 1986 al 1999. È stato inoltre professore invitato alla Cornell University di New York, a Chicago, nel Kansas, nella California, a Berkeley, nel Colorado, nel Connecticut, ad Amburgo, a Losanna e a Tolosa. Nel 1982 è stato anche professore di Letteratura francese all’Università John-Hopkins di Baltimora. Fra le sue numerose pubblicazioni citiamo La découverte scientifique (1999) e Le savoir des plantes (1999). Fra i suoi riconoscimenti ricordiamo il Premio dell’Accademia delle Scienze (1981) e il Premio Maurice Pérouse della Fondation de France (1999). Attualmente, Pierre Laszlo divide la sua vita vive fra la California e il Sud della Francia.

 

Continue readingIntervista a Pierre Laszlo, maggio 2001