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International audience; We report the design, elaboration and measurements of an innovative planar thermoelectric (TE) devices made of a large array of small mechanically suspended nanogenerators (nanoTEG). The miniaturized TE generators based on SiN membranes are arranged in series and/or in parallel depending on the expected final resistance adapted to the one of the load. The microstructuration allows, at the same time, a high thermal insulation of the membrane from the silicon frame and high thermal coupling to its environment (surrounding air, radiations). We show a ratio of 60% between the measured effective temperature of the membrane, (and hence of the TE junctions), and the available temperature of the heat source (air). The thermal gradient generated across the TE junction reaches a value as high as 60 kelvin per mm. Energy harvesting with this planar TE module is demonstrated through the collected voltage on the TE junctions when a temperature gradient is applied, showing a harvested power on the order of 0.3 µWatt for a 1 cm 2 chip for an effective temperature gradient of 10 K. The optimization of nanoTEGs performances will increase the power harvested significantly and permit to send a signal by a regular communication protocol and feed basic functions like temperature measurement or airflow sensing.

Here we report the design, the elaboration and the measurement of an innovative planar thermoelectric (TE) devices made of large array of suspended nanogenerators [1]. The miniaturized TE generators are arranged in serial and/or in parallel depending on the expected final resistance adapted to the charge. Devices are elaborated using MEMS clean room processes. They can produce enough power (below 100 ¼Watt) to send a signal with common communication protocol and feed basic functions, for example a temperature measurement.

Radio telemetry equipment has significantly improved over the last 10–15 years and is increasingly being used in research for monitoring a variety of physiological parameters in non-sedated animals. The aim of this review is to provide an update on the current state of development of radio telemetry for recording respiration. Our literature review found only rare reports of respiratory studies via radio telemetry. Much of this article will hence report our experience with our custom-built radio telemetry devices designed for recording respiratory signals, together with numerous other physiological signals in lambs. Our current radio telemetry system allows to record 24 simultaneous signals 24 h/day for several days. To our knowledge, this is the highest number of physiological signals, which can be recorded wirelessly. Our devices have been invaluable for studying respiration in our ovine models of preterm birth, reflux laryngitis, postnatal exposure to cigarette smoke, respiratory syncytial virus infection and nasal ventilation, all of which are relevant to neonatal respiratory problems.

International audience; We describe a setup including a microscope to study volumes of a few μm^3 by static and dynamic light scattering (DLS) in a backscattering configuration. Light scattered by individual objects of micrometric size can be analyzed in the 400 - 800 nm spectral range. This setup can also be employed to study both diluted and concentrated colloidal solutions by DLS measurements. For diluted solutions we found evidence of the fluctuations of the number of particles in a confocal volume. We discuss their contribution to the autocorrelation function of the scattered intensity measured as a function of time.

This study was aimed at validating the use of a custom-made wireless pulse oximeter in freely moving lambs, using radiotelemetry transmission. First, measurements obtained simultaneously using the new, wireless oximeter and a standard commercially-available pulse oximeter (Nonin 8500) were compared in five lambs during 5 min episodes of normoxia, hypoxia and hyperoxia. Correlation between the two oximeters for both SpO 2 and heart rate was very good, regardless of oxygenation conditions. Secondly, the capabilities of our device were assessed during more than 45 h of polysomnographic recordings in seven lambs. According to the plethysmographic pulse waveform, reliable SpO 2 values were obtained in more than 85% of recording time. Multiple decreases in SpO 2 were readily observed after spontaneous apneas in preterm lambs. It is concluded that our wireless pulse oximeter performs as reliably as a standard pulse oximeter for monitoring SpO 2 variations in lambs, and offers new perspectives for researchers interested in continuous monitoring of oxygenation throughout sleep stages and wakefulness.