Comparative study of multilayers used in monochromators for synchrotron-based coherent hard X-ray imaging.

A systematic study is presented in which multilayers of different composition (W/Si, Mo/Si, Pd/B(4)C), periodicity (from 2.5 to 5.5 nm) and number of layers have been characterized. In particular, the intrinsic quality (roughness and reflectivity) as well as the performance (homogeneity and coherence of the outgoing beam) as a monochromator for synchrotron radiation hard X-ray micro-imaging are investigated. The results indicate that the material composition is the dominating factor for the performance. By helping scientists and engineers specify the design parameters of multilayer monochromators, these results can contribute to a better exploitation of the advantages of multilayer monochromators over crystal-based devices; i.e. larger spectral bandwidth and high photon flux density, which are particularly useful for synchrotron-based micro-radiography and -tomography.

[Changes of the course of experimental epileptic attacks by curarization]. / Modification de l'évolution de crises comitales expérimentales par la curarisation.

In our studies on the Rabbit, the time of seizure in increase after curarization. The curare do not pass through the blood brain barrier ; the action of drug can not be a direct action on the central nervous system.

Pharmacokinetics of intravenous camazepam in dogs.

Free plasma concentrations were studied after i.v. administration of three different doses (2.5, 5, 7.5 mg/kg respectively) of 3-N,N-dimethylcarbamoyloxy-7-chloro-5-phenyl-1-methyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one (camazepam) to three healthy male mongrel dogs. Total plasma concentration was measured by a specific gas-liquid chromatography technique. The protein binding of camazepam in dog plasma was studied by using the equilibrium dialysis method and found to vary from 88.5 to 76.7% when the total drug concentration increased from 8 ng/ml to 8 micrograms/ml. For the subsequent pharmacokinetic analysis the calculated free camazepam plasma concentrations were used. The superposition principle was applied to each dog demonstrating that a linear pharmacokinetic model was applicable. Computer analysis showed that the pharmacokinetics of camazepam could be conveniently described by a three-compartment model assuming that the drug elimination occurred from the central compartment exclusively. The half-life of the terminal elimination phase ranged from 6.4 to 10.5 h, a finding which might suggest that camazepam could exhibit long-lasting effects.