Aspects of harmonisation of individual monitoring for external radiation in Europe: Conclusions of a EURADOS action

Following the publication of the EU Council Directive 96/29, EURADOS coordinated two working groups (WGs) for promoting the process of harmonisation on individual monitoring of occupationally exposed persons in Europe. An overview of the major findings of the second WG is presented. Information on the technical and quality standards and on the accreditation and approval procedures has been compiled. The catalogue of dosimetric services has been updated and extended. An overview of national regulations and standards for protection from radon and other natural sources in workplaces has been made, attempting to combine the results from individual monitoring for external, internal and workplace monitoring. A first status description of the active personal dosemeters, including legislative and technical information, and their implementation has been made. The importance of practical factors on the uncertainty in the dose measurement has been estimated. Even if a big progress has been made towards harmonisation, there is still work to be don

Stereoselectivity in (Z)-Vinylmetal Additions to the Dictyostatin C1\u2013C9 \u3b2-Silyloxy Aldehyde

(Z)-Vinyl iodides 6a\u2013d were synthesized in high yield with good diastereo- and enantioselectivity using a Marshall\u2013Tamaru, Pd-catalyzed allenylzinc reaction as the key step. The addition of 6a\u2013d to the dictyostatin C1\u2013C9 \u3b2-silyloxy aldehyde 5 was carried out through the vinyllithium and lithium vinylzincate routes. The lithium vinylzincate additions always proceeded in higher yields and gave fewer side products than the corresponding vinyllithium additions. The configuration of the newly created C9 stereocenter was assigned through Rychnovsky\u2019s acetonide 13C NMR method. The diastereoselectivity in this particular type of (Z)-vinylmetal addition reaction appears to be controlled by a subtle balance between the intrinsic stereochemical preference of the \u3b2-silyloxy aldehyde (1,3-anti-selective) and that of the chiral lithium (Z)-vinylzincates. The latter becomes more influential with increasing stereochemical complexity, that is, passing from a stereodyad (6a,6b) to a stereotriad (6c,6d)

Aspects of harmonisation of individual monitoring for external radiation in Europe: Conclusions of a EURADOS action

Following the publication of the EU Council Directive 96/29, EURADOS coordinated two working groups (WGs) for promoting the process of harmonisation on individual monitoring of occupationally exposed persons in Europe. An overview of the major findings of the second WG is presented. Information on the technical and quality standards and on the accreditation and approval procedures has been compiled. The catalogue of dosimetric services has been updated and extended. An overview of national regulations and standards for protection from radon and other natural sources in workplaces has been made, attempting to combine the results from individual monitoring for external, internal and workplace monitoring. A first status description of the active personal dosemeters, including legislative and technical information, and their implementation has been made. The importance of practical factors on the uncertainty in the dose measurement has been estimated. Even if a big progress has been made towards harmonisation, there is still work to be done. © 2006 Oxford University Press

TRACTION PATTERNS OF TUMOR CELLS

International audienceThe traction exerted by a cell on a planar deformable substrate can be in- directly obtained on the basis of the displacement field of the underlying layer. The usual methodology used to address this inverse problem is based on the exploitation of the Green tensor of the linear elasticity problem in a half space (Boussinesq problem), coupled with a minimization algorithm under force penalization. A possible alternative strategy is to exploit an adjoint equation, obtained on the basis of a suitable minimiza- tion requirement. The resulting system of coupled elliptic partial differential equations is applied here to determine the force field per unit surface generated by T24 tumor cells on a polyacrylamide substrate. The shear stress obtained by numerical integration provides quantitative insight of the traction field and is a promising tool to investigate the spatial pattern of force per unit surface generated in cell motion, particularly in the case of such cancer cells