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In this work, the influence of the powder particle morphology on the microstructural morphology and structural texture levels of tetragonal tungsten bronze Pb0·56Ba0·44Nb2O6ceramics was investigated. Powders were obtained by solid state reaction synthesis with different aspect ratios and densified through biaxial hot forging. A texture diffractometer was used to investigate the preferential orientation of the crystallographic planes and their relation to the microstructural morphology of the hot forged samples. The results showed that the higher the particle aspect ratio before firing, the higher the structural texture level of the sample after hot forging process. The highest anisotropy of the dielectric properties was observed in the sample with enhanced texture. Therefore, control of the particle morphology of the lead barium niobate precursor powder is very useful for obtaining ceramics with high texture levels and desirable anisotropic properties.

We describe the discovery and the structure−activity relationship of a new series of quinoline derivatives acting as selective and highly potent noncompetitive mGlu1 antagonists. We first identified cis-10 as a fairly potent mGlu1 antagonist (IC50 = 20 nM) in a cell-based signal transduction assay on the rat mGlu1 receptor expressed in CHO-K1 cells, and then we were able to design and synthesize highly potent compounds on both rat and human mGlu1 receptors as exemplified by compound cis-64a, which has an antagonist potency of 0.5 nM for the human mGlu1 receptor. We briefly present and discuss the in vitro metabolic stability of the compounds in human liver microsomes. We finally report the pharmacokinetic properties of our lead compound cis-64a.

Simultaneous measurements collected by a network of landers spread over the surface of Mars will provide a unique leap forward in our knowledge of Mars. This is the objective of the NetLander (for Network Lander) project developed by CNES (French Space Agency), FMI (Finnish Meteorological Institute), IfP (Institute fu¨r Planetologie - Mu¨nster) in cooperation with a number of institutes in Europe and in the United States. The NetLander mission will deploy four identical landers on the surface of Mars. Each lander includes a scientific payload with instrumentation aimed at studying the interior of Mars, the atmosphere, the sub-surface, as well as the ionospheric structure and geodesy. The European NetLander mission will be launched in 2007 with the orbiter developed by CNES in the framework of the French Mars exploration program. After a cruise phase lasting several months, the NetLander probes will be separated from the orbiter and targeted to their landing sites. NetLander has successfully completed the phase A study. Its Entry, Descent and Landing System uses a front-shield, parachutes and air-bags. On the surface of Mars, NetLander will use solar arrays and batteries for its power supply. Particular attention is paid to the definition of this power supply system, which should provide enough energy throughout the mission, with a duration objective of one Martian year. Telecommunications will be possible via data relay satellites in orbit around Mars.

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