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Probing consciousness in noncommunicating patients is a major medical and neuroscientific challenge. While standardized and expert behavioral assessment of patients constitutes a mandatory step, this clinical evaluation stage is often difficult and doubtful, and calls for complementary measures which may overcome its inherent limitations. Several functional brain imaging methods are currently being developed within this perspective, including fMRI and cognitive event-related potentials (ERPs). We recently designed an original rule extraction ERP test that is positive only in subjects who are conscious of the long-term regularity of auditory stimuli.

Fiber drawing conditions (temperature, speed, tension) have been investigated to reach very low losses (0.20 dB/km at 1.55 μm) with MCVD triangular core-profile preforms. Such dispersion-shifted fibers exhibit good mechanical, splicing, cabling, and ageing properties.

The anticipated increase in demand for high–quality single–mode optical fibres requires the development of cost–effective alternatives to present methods of preform manufacture. Alcatel is closely involved in the improvement of existing production processes and the development of new and promising alternatives.

The authors demonstrate that single stage phosphorus-aluminium-codoped EDFAs greatly increase the usable spectral bandwidth for long-haul submarine applications. With such an amplifier, a total gain excursion of 5 dB was measured for eight WDM channels spanning 11 nm, with a total power budget of 1150 dB.