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The French Transportable Laser Ranging Station (FTLRS)is a highly mobile satellite laserranging (SLR) system dedicated to the trackingof geodetic satellites equipped withretroreflectors. This station weighs only 300kg witha 13-cm diameter telescope and is housedin eight containers. The reliability of such a station and its accuracy of 2 cmin real field experiment conditionswere demonstrated during a first field campaign carried outfrom October 1996 to February1997 near Ajaccio on Corsica Island, France. The results ofthis probatory experiment suggestedthat several technical improvements and some modificationswere necessary for JASON-1validation and calibration phase and for new applicationssuch as the Time Transfer by LaserLink (T2L2) experiment. A first change concerns theuse of a new laser wavelength (green instead ofinfrared) and of a new avalanche photodiode with atime walk compensation system. Anotherchange is the installation of a coaxial cabletransmitting directly the signal coming from thereturn detector. Finally, a new calibration systemwas developed with several other changes.A short description of the system is first given.Then, the major changes and the main resultsof ground accuracy tests are summarized and presented.

The aim of this prospective, placebo-controlled study was to asses if unilaterally inhaled nitric oxide 20 ppm cold treat hypoxaemia during one-lung ventialtion. Sixty patients undergoing pulmonary resection using a lateral thoracotomy were allocated randomly to a control or nitric oxide group (NO group). During one-lung ventilation in the lateral decubitus position, the lungs were ventilated mechanically with 90% oxygen-10% nitrogen. After randomization, if Pa_O2 decreased to less than 9.3 kPa using one-lung ventilation, nitric oxide 20 ppm or nitrogen was added to the inspired gas. The criterion for treatment efficacy was an increase in Pa_O2 to greater than 9.3 kPa after gas administration. Eight patients in the control group and eight in group NO experienced hypoxaemia during one-lung ventilation. Pa_O2 was not significantly different in the two groups at the time of gas administration (control group mean 8.0 (SD 0.6) kPa; NO group 8.5 (0.5) kPa). The efficacy criterion was reached in two of eight patients in the control and NO groups. The results of this study showed that inhaled nitric oxide 20 ppm, administered in the dependent lung, was not superior to nitrogen in the treatment of hypoxaemia during one-lung ventilation. Nitric oxide should not be recommended as an alternative to conventional management of hypoxaemia in this condition.
Key words: phamacology, nitric oxide; ventilation, one-lung ventilation; surgery, thoracic; hpoxaemia

The aim of this prospective, placebo-controlled study was to assess if unilaterally inhaled nitric oxide 20 ppm could treat hypoxaemia during one-lung ventilation. Sixty patients undergoing pulmonary resection using a lateral thoracotomy were allocated randomly to a control or nitric oxide group (NO group). During one-lung ventilation in the lateral decubitus position, the lungs were ventilated mechanically with 90% oxygen--10% nitrogen. After randomization, if PaO2 decreased to less than 9.3 kPa during one-lung ventilation, nitric oxide 20 ppm or nitrogen was added to the inspired gas. The criterion for treatment efficacy was an increase in PaO2 to greater than 9.3 kPa after gas administration. Eight patients in the control group and eight in group NO experienced hypoxaemia during one-lung ventilation. PaO2 was not significantly different in the two groups at the time of gas administration (control group mean 8.0 (SD 0.6) kPa; NO group 8.5 (0.5) kPa). The efficacy criterion was reached in two of eight patients in the control and NO groups. The results of this study showed that inhaled nitric oxide 20 ppm, administered in the dependent lung, was not superior to nitrogen in the treatment of hypoxaemia during one-lung ventilation. Nitric oxide should not be recommended as an alternative to conventional management of hypoxaemia in this condition.

In a previous work [Macromolecules 1998, 31, 6426] the preparation technique of a latex of poly(β-hydroxyoctanoate) (PHO) obtained from Pseudomonas oleovorans grown at high cell density on sodium octanoate was presented. The resulting films displayed typical properties of thermoplastic elastomer. Depending on the experimental purification conditions, fully amorphous PHO films can be obtained. Nanocomposite materials were prepared using this latex as a matrix and using a colloidal suspension of hydrolyzed starch or cellulose whiskers as a natural and biodegradable filler. After stirring, the preparations were either cast and evaporated or freeze-dried and molded. High-performance materials were obtained from these systems, preserving the natural character of PHO. The resulting properties were strongly related to the aspect ratio L/d (L being the length and d the diameter) of the filler and to the geometric and mechanical percolation effects. In addition, specific polymer−filler interactions and geometrical constraint due to the particle size of the latex have to be considered to account for the mechanical reinforcement effect of cellulose whiskers.

Strain X4 was isolated several years ago from an anaerobic mesophilic plant treating vegetable cannery waste waters. It was the first example of propionic fermentation from ethanol. Morphologic and physiologic characterizations of the strain are presented here. This strain is described as type strain of a new species, Clostridium neopropionicum sp. nov. Whole cells of strain X4 ferment [1-13C]ethanol and CO2 to [2-13C]propionate, [1-13C]acetate and [2-13C]propanol, suggesting the absence of a randomizing pathway during the propionate formation. Enzymes involved in this fermentation were assayed in cell-free extracts of cells grown with ethanol as sole substrate. Alcohol dehydrogenase, aldehyde dehydrogenase, phosphate acetyl transferase, acetate kinase, pyruvate synthase, lactate dehydrogenases, and the enzymes of the acrylate pathway were detected at activities sufficient to be involved in ethanol fermentation. The same pathway may be used for the degradation of lactate or acrylate to acetate.

A latex of poly(β-hydroxyoctanoate) was obtained from Pseudomonas oleovorans grown at high cell density on sodium octanoate. A fermentation using a pH-stat control of octanoate concentration as well as the purification steps using sodium hypochlorite were described. It was observed that latex stabilization occurred spontaneously due to the persistence around the polymer granules of the murein sacculus, which envelopes the bacterial cell. Films were processed by casting and evaporating the polymeric aqueous suspension and were characterized by scanning electron microscopy, wide-angle X-ray scattering, dynamic mechanical analysis, and tensile tests. It was shown that the optimal conditions for the bacteria digestion correspond to a hypochlorite concentration between 21 and 26 mmol of NaOCl/g of biomass. These conditions enable latex stabilization and satisfactory mechanical properties of the resulting film.

Succinate dehydrogenase was purified from the particulate fraction of Desulfobulbus. The enzyme catalysed both fumarate reduction and succinate oxidation but the rate of fumarate reduction was 8‐times less than that of succinate oxidation. Quantitative analysis showed the presence of 1 mol of covalently bound flavin and 1 mol of cytochrome bper mol of succinate dehydrogenase. The enzyme contained three subunits with molecular mass 68.5, 27.5 and 22 kDa. EPR spectroscopy indicated the presence of at least two iron sulfur clusters. 2‐Heptyl‐4‐hydroxy‐quinoline‐N‐oxide inhibited the electron‐transfer between succinate dehydrogenase and a high redox potential cytochrome c3from Desulfobulbus elongatus.

The T2L2 experiment allows the synchronisation of remote clocks on Earth, and the monitoring of a satellite clock with an accuracy in the 50 ps range. It is based on the propagation of light pulses in space which is better controlled than the radio waves propagation. Some new optical timer and the definition of a new time origin allow direct accurate time transfer without external calibration. The time equations and the uncertainty budget are presented so as to justify the announced performance. This optical time transfer associated to an ultra-stable clock in space has many scientific application as the study of some aspects of the gravitation.