Despite the very difficult conditions that are still preventing SOLEIL from functioning under normal operating conditions, due principally to the unavailability of the cooling system for the beamlines, a first experimental result was obtained on Wednesday, March 21, 2007 using the DIFFABS beamline. This line, which is currently in the testing phase, is dedicated to the analysis of a wide variety of materials via experiments in the absorption and diffraction of “hard” X-rays.

The study involves kidney stones, which are responsible for nephritic colic, a condition that affects 10% of the European population. The experiments involved determination of the density of zinc and of the environment of this element within the stones, in order to better understand the initial stages of their formation. Why zinc? Kidney stones are made up of a protein matrix and a mineral (calcium phosphate) present in the form of a grouping of nanocrystals a hundred nanometers in size (1 nm = 1 thousand millionth of a meter). Elements like zinc are likely, by catalyzing the formation of these nanocrystals, to speed up the formation of kidney stones.

This project, whose principal objective in this testing phase is to qualify the instruments installed on the DIFFABS beamline, was conducted as part of a collaboration between the SOLEIL DIFFABS team, directed by D. Thiaudière, and D. Bazin (Laboratory for Solid State Physics, University of Paris XI and CNRS) and Drs. M. Daudon (Cristal Laboratory, Hôpital Necker, AP-HP) and X. Carpentier and O. Traxer, urologists at Hôpital Tenon, (AP-HP). It is part of a multidisciplinary approach dedicated to the study of kidney stones on different scales , on the mesoscopic one (Electron Scanning Microscope) with G. Matzen and E. Véron (CRMHT, CNRS Orléans) and on the nanometric onevia neutronic diffraction with G. André (LLB CEA/CNRS Saclay).

Photograph of the DIFFABS assembly showing kidney stone under X-ray		Oxalocalcic stone formed by papillary calcification