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International audience; The Port-Cros National Park (PCNP), established in 1963, was one of the earliest terrestrial and marine parks in the Mediterranean Sea. From 2012, it engaged in a major redefinition and extension of its territory (N-PCNP—New Port-Cros National Park). This case is particularly interesting insofar as the protected area has been competently and efficiently managed since its creation, and protection and management measures have been strictly implemented: in the Mediterranean, the PCNP has often been considered as a benchmark. Here, we critically analyse almost 60 years of the management of the biodiversity and the human uses, with their share of successes and failures, certain operations which are today regarded as errors, and a doctrine today of a priori non-interventionism, in contrast to the doctrine in vogue in the early years. Of particular interest is the change in outlook with regard to actions favouring flagship species, such as building a tower for bats, setting up artificial nests for seabirds, and constructing an artificial reef at sea. The question of the natural arrival of the wild boar, a native species, and the hostility of the public and some species-centred scientists, is particularly instructive. We analyse these changes in the light of the ongoing trends in concepts in ecology and nature conservation, and the shift from a species-centred to an ecosystem-centred approach. It is worth emphasizing that a critical review of almost 60 years of management is a very rare exercise in a national park anywhere in the world.

International audience; A passive bistatic ground-based synthetic aperture radar (PB-GB-SAR) system without a dedicated transmitter has been developed by using commercial-off-the-shelf (COTS) hardware for local-area high-resolution imaging and displacement measurement purposes. Different from the frequency-modulated or frequency-stepped continuous wave signal commonly used by GB-SAR, the continuous digital TV signal broadcast by a geostationary satellite has been adopted by PB-GB-SAR. In order to increase the coherence between the reference and surveillance channels, frequency and phase synchronization of multiple low noise blocks (LNBs) has been conducted. Then, the back-projection algorithm (BPA) and the range migration algorithm (RMA) have been modified for PB-GB-SAR to get the focused SAR image. Field experiments have been carried out to validate the designed PB-GB-SAR system and the proposed methods. It has been found that different targets within 100 m (like the fence, light pole, tree, and car) can be imaged by the PB-GB-SAR system. With a metallic plate moved on a positioner, it has been observed that the displacement of the target can be estimated by PB-GB-SAR with submillimeter accuracy.

An aspergilloma is a well-recognized lesion of the lung caused most of the time by the fungus Aspergillus fumigatus. Its main complication is hemoptysis and has been very rarely associated with tension pneumothorax. We present the case of a 47-year-old man with a history of treated and healed tuberculosis, which was successfully managed in our service for a ruptured right upper lobe complexed aspergilloma, complicated by a massive and tension pneumothorax. The patient underwent thoracotomy and lung resection with quick recovery. Conclusively, although rare, an aspergilloma may rupture and cause a life-threatening air leakage.

An aspergilloma is a well-recognized lesion of the lung caused most of the time by the fungus Aspergillus fumigatus. Its main complication is hemoptysis and has been very rarely associated with tension pneumothorax. We present the case of a 47-year-old man with a history of treated and healed tuberculosis, which was successfully managed in our service for a ruptured right upper lobe complexed aspergilloma, complicated by a massive and tension pneumothorax. The patient underwent thoracotomy and lung resection with quick recovery. Conclusively, although rare, an aspergilloma may rupture and cause a life-threatening air leakage.

International audience

International audience; In this paper, a passive measurement system is used to explore the phase noise of high overtone bulk acoustic wave resonators. The chosen overtone is around 373 MHz and the temperature coefficient of frequency at room temperature is 4 ppm/K. The 1/f noise is clearly shown and a flicker floor of about σy_floor = 1.5×10-11 is demonstrated.

International audience

International audience; The project aims to develop a 4.596 GHz MEMS HBAR-based microwave voltage controlled oscillator devoted to be used as a local oscillator in a Cs vapor microcell-based CPT atomic clock. These miniature high-spectral purity oscillators are interesting candidates to replace conventional local oscillator architectures using a 4.6 GHz VCO phase-locked to a 10 MHz quartz oscillator (TCXO) through a fractional N-PLLsystem. Today, about a half of the total power consumption of miniature atomic clocks is dedicated to the local oscillator module. The development of MEMS HBAR oscillators stands as an exciting opportunity to reduce drastically the power consumption of miniature atomic clocks, with additional improvement of absolute phase noise performances. These aspects could help miniature CPT-based atomic clocks to be of great interest in mobile and embedded systems where spectral purity of the local clock is crucial, such as radar defense systems.

International audience; We report the detailed characterization of 2.3 GHz AlN-Sapphire high-overtone bulk acoustic resonators (HBARs), with a typical loaded Q-factor of 25–30 103 , 15–20 dB insertion loss, and resonances separated by about 10 MHz. The temperature coefficient of frequency of HBARs is measured to be about 25 ppm/K. We observe at high-input microwave power a significant distortion of the HBAR resonance lineshape, attributed to non-linear effects. The power-induced fractional frequency variation of the HBAR resonance is measured to be about 5 1010/lW. The residual phase noise of a HBAR is measured in the range of 110 to 130 dBrad2/Hz at 1 Hz Fourier frequency, yielding resonator fractional frequency fluctuations at the level of 205 to 225 dB/Hz at 1 Hz and an ultimate HBAR-limited oscillator Allan deviation about 7 1012 at 1 s integration time. The 1/f noise of the HBAR resonator is found to increase with the input microwave power. A HBAR resonator is used for the development of a low phase noise 2.3 GHz oscillator.An absolute phase noise of 60, 120, and 145 dBrad2 /Hz for offset frequencies of 10 Hz, 1 kHz, and 10 kHz, respectively, in excellent agreement with the Leeson effect, is measured.

The development of future telecommunication systems requires the miniaturization of circulators. Apart from using planar technologies, removing magnets appears as one of the main solutions to improve the integration of circulators. This technological step requires the use of oriented hexaferrites in their remanent state. Thus, the unusual properties of these materials were used to design and realize a millimeter-wave self-biased circulator in rectangular waveguide. Without magnets, insertion losses of 1.79 dB and an isolation level of 28.1 dB were measured at 41.4 GHz. These results demonstrate the strong potential of these materials for the design of self-biased circulators.

International audience; The interest of surface acoustic wave devices (SAW) operating in radio-frequency range is their very high compactness, low losses and high quality factor. Thus, they are very interesting components for the stabilization of ultra-low noise on-board oscillators operating in direct bands. The need for working frequency beyond 3 GHz has lead SAW manufacturers to develop multilayer diamond-based waveguides providing higher phase velocity than conventional single-crystal materials, typically ranging from 7 to 12 km.s-1 for elliptically polarized waves. The very problem in this approach is the excitation and detection of acoustic waves requiring a high quality piezoelectric layer of less than one micrometer thick with physical properties as close as possible to the tabulated ones. An ultimate control of the film thickness and roughness is required to control dispersion and diffusion losses. In this work, we investigated a structure based on Nano-Crystalline Diamond (NCD). The waves are launched and detected using a Zinc Oxide film deposited atop the diamond layer, yielding notable dispersive properties of the device. In this way, technological developments have been achieved (NCD growth, piezoelectric layer deposition, e-beam and optical lithography) to build SAW devices taking advantage of NCD films to try and benefit from their suspected low acoustic damping. Results show the possibility of developing devices operating between 2 and 3 GHz at minimum, having losses lower than 10 dB. At last, devices whose dimensions are compatible with conventional lithography processes, show resonances at more than 4 GHz with less than 8 dB of insertion loss, what is, at the knowledge of the authors, the best experimental result for such devices. To compare with previous results, a device operating near 3 GHz has been used to stabilize an oscillator. Short term stability has been measured at 10-8 s-1 and a phase noise floor was observed at -170 dB at 3 MHz from the carrier. Although not yet meeting the expected requirements, these results show the impact of loss reduction and general device improvement and allow for preparing future work near 5 GHz.

International audience; The role of the phase noise of a local oscillator driving a pulsed-mode RADAR used for probing surface acoustic wave sensors is investigated. The echo delay, representative of the acoustic velocity, and hence the physical quantity probed by the sensor, is finely measured as a phase. Considering that the intrinsic oscillator phase fluctuation defines the phase noise measurement resolution, we experimentally and theoretically assess the relation between phase noise, measurement range, and measurand resolution.

International audience; We have investigated the possibility to use carbon-diamond layers exhibiting nano-sized grains for the fabrication of SAW resonators. One of the main purpose was to check the influence of the grain size on the resonator's spectral signature and to evaluate the fabrication of high frequency sources along this approach. We have investigated various material combinations on Nano-Carbon-Diamond (NCD) layers grown along different techniques (nano-seeding, BEN, followed by MPCVD). The best configuration was based on ZnO/NCD material combination provided the piezoelectric layer was deposited on the so-called nucleation surface of the NCD. Numerous resonators have been fabricated on such substrates, allowing to characterize and exploit the resonance near 3 GHz. An oscillator then was built using such a configuration: its stability has been measured near 10-7 and its phase noise was found near −100 dBc.Hz-1 at 10 kHz.

International audience; We demonstrate that single-piezoelectric substrate-based acoustic transducers act as ideal sensors for probing with various RADAR strategies. Because these sensors are intrinsically passive devices working in the radiofrequency range, they exhibit improved interrogation range and robustness with respect to silicon-based radio frequency identification tags. Both wideband (acoustic delay lines) and narrowband (acoustic resonators) transducers are shown to be compatible with pulse-mode and frequency-modulated continuous-wave RADAR strategies, respectively. We particularly focus on the ground-penetrating RADAR (GPR) application in which the lack of local energy source makes these sensors suitable candidates for buried applications in roads, building or civil engineering monitoring. A novel acoustic sensor concept - high-overtone bulk acoustic resonator - is especially suited as sensor interrogated by a wide range of antenna set, as demonstrated with GPR units working in the 100 and 200 MHz range.

International audience; Surface acoustic wave (SAW) devices are currently used as passive remote-controlled sensors for measuring various physical quantities through a wireless link. Among the two main classes of designs-resonator and delay line-the former has the advantage of providing narrow-band spectrum informations and hence appears compatible with an interrogation strategy complying with Industry-Scientific-Medical regulations in radio-frequency (rf) bands centered around 434, 866, or 915 MHz. Delay-line based sensors require larger bandwidths as they consists of a few interdigitated electrodes excited by short rf pulses with large instantaneous energy and short response delays but is compatible with existing equipment such as ground penetrating radar (GPR). We here demonstrate the measurement of temperature using the two configurations, particularly for long term monitoring using sensors buried in soil. Although we have demonstrated long term stability and robustness of packaged resonators and signal to noise ratio compatible with the expected application, the interrogation range (maximum 80 cm) is insufficient for most geology or geophysical purposes. We then focus on the use of delay lines, as the corresponding interrogation method is similar to the one used by GPR which allows for rf penetration distances ranging from a few meters to tens of meters and which operates in the lower rf range, depending on soil water content, permittivity, and conductivity. Assuming propagation losses in a pure dielectric medium with negligible conductivity (snow or ice), an interrogation distance of about 40 m is predicted, which overcomes the observed limits met when using interrogation methods specifically developed for wireless SAW sensors, and could partly comply with the above-mentioned applications. Although quite optimistic, this estimate is consistent with the signal to noise ratio observed during an experimental demonstration of the interrogation of a delay line buried at a depth of 5 m in snow.

The objective of this study was to examine the impact that two social housing complexes have had on their residents' quality of life. These two complexes, known as Tannery Court Co-operative Ltd., target a specific segment of the affordable housing market: non-elderly singles. A mixed-methods approach was used to assess the quality of life of residents. The data collection strategy used semi-structured interviews conducted with the help of a questionnaire. A total of 43 interviews were completed at the two building sites. Analysis of interview and questionnaire data identified six areas of improvement in residents' quality of life. These are life in general (an overarching dimension), housing (the focus of the Tannery Court intervention), neighbourhood (including safety and appearance), food , self-confidence (an enabling dimension for future development of projects and goals among the residents), and financial situation (a key dimension because of its multiple impacts on other aspects of life). RESUME L'objectif de cette recherche etait d'evaluer l'impact des deux complexes de logements cooperatifs Tannery Court sur la qualite de vie des residants. Ces complexes ciblent un segment particulier du marche du logement social, les celibataires d'âge actif et vivant en deca du seuil de la pauvrete. Cette etude utilise une methodologie mixte pour evaluer la situation et la qualite de vie des residants. La strategie de cueillette de donnees s'appuie sur des entrevues semi-dirigees effectuees a l'aide d'un questionnaire. Au total, nous avons complete 43 entrevues. Six aspects de la qualite de vie se sont ameliores de facon significative. Il s'agit de la vie en general (une dimension globale), le logement (l'objectif premier vise par l'equipe de Tannery Court), le quartier de residence (dimensions importantes de la localisation d'un complexe comme la securite et l'apparence) la confiance en soi (une dimension cle pour le developpement futur de projets et d'objectifs pour les residants), la nourriture (en raison de l'acces a des electromenagers) et la situation financiere (une dimension majeure etant donne son impact sur les autres composantes de la vie).

International audience; Within the context of probing acoustic wave resonators acting as wireless, passive sensors, we present a strategy for wireless monitoring of surface accoustic wave (SAW) resonators using a frequency modulation based interrogation method. The basic principle is the conversion of frequency modulation to amplitude modulation by the resonator through its S-11 transfer function. An ARM-7 based central processing unit synchronizes the narrow-band probing pulse emission, emission to reception switching, data sampling and data processing. A closed loop control keeps the emitted carrier frequency at the resonance frequency of the sensor: we demonstrate a resolution of 2Hz on the resonance freqeuncy identification at 1s integration time, limited by this proportional feedback loop.

International audience; We demonstrate the wireless conversion of frequency modulation to amplitude modulation by radio frequency resonators as means of accurately determining the resonance frequency of passive acoustoelectronic sensors. The emitted frequency modulated radio frequency pulses are generated by a pulsed radar for probing a surface acoustic wave based sensor. The sharp sign transition of the amplitude modulated received signal provides a signal on which a feedback loop is locked to monitor the resonance signal. The strategy is demonstrated using a full software implementation on a generic hardware, resulting in 2 Hz resolution at 1 s integration time limited by the proportional feedback loop.

International audience; Monitoring physical quantities using acoustic wave devices can be advantageously achieved using the wave characteristic dependence to various parametric perturbations (temperature, stress, and pressure). Surface acoustic wave (SAW) resonators are particularly well suited to such applications as their resonance frequency is directly influenced by these perturbations, modifying both the phase velocity and resonance conditions. Moreover, the intrinsic radio frequency (rf) nature of these devices makes them ideal for wireless applications, mainly exploiting antennas reciprocity and piezoelectric reversibility. In this paper, we present a wireless SAW sensor interrogation unit operating in the 434 MHz centered ISM band-selected as a tradeoff between antenna dimensions and electromagnetic wave penetration in dielectric media-based on the principles of a frequency sweep network analyzer. We particularly focus on the compliance with the ISM standard which reveals complicated by the need for switching from emission to reception modes similarly to radar operation. In this matter, we propose a fully digital rf synthesis chain to develop various interrogation strategies to overcome the corresponding difficulties and comply with the above-mentioned standard. We finally assess the reader interrogation range, accuracy, and dynamics.

International audience; The thermal sensitivity of acoustic-wave-based devices still is an optimization key-point for various applications (filters, sources, sensors). As the architecture of such devices becomes more and more complex to fit the RF manufacturer requirements. simple analytical models usually exploited to optimize their frequency thermal drift are found obsolete. The optimization of these complex periodic wave-guide thermal sensitivities require the development of simulation tools capable to address the problem. This paper describes a Finite Element Analysis-Boundary Element Method (FEA/BEM) model allowing for the simulation any 2D and 3D periodic wave-guide thermal sensitivity. and more specifically the extraction of the corresponding Temperature Coefficient of Frequency (TCF). Validation of the computation approach first is reported. Its capabilities then are illustrated by computing the TCF of Love wave resonator on quartz.

International audience; The development of new surface acoustic wave devices exhibiting complicated electrode patterns or layered excitation transducers has been favored by an intense innovative activity in this area. For instance, devices exhibiting interdigital transducers covered by piezoelectric or dielectric layers have been fabricated and tested, but the design of such structures requires simulation tools capable to accurately take into account the actual shape of the wave guide elements. A modeling approach able to address complicated surface acoustic wave periodic structures (defined in the saggital plane) exhibiting any geometry then has been developed and implemented. It is based on the combination of a finite element analysis and a boundary element method. A first validation of the computation is reported by comparison with standard surface wave devices. Surface transverse wave resonators covered by amorphous silica have been built and consequently used for theory/experiment assessment. Also the case of recessed electrodes has been considered. The proposed model offers large opportunities for modeling any two-dimensional periodic elastic wave guide.

Objectifs Ce travail a été entrepris dans l’optique de tester les activités antimicrobiennes de quatre espèces d’Eucalyptus d’origine australiennes, E. dives, E. gunnii, E. olida et E. staigeriana contre cinq micro-organismes d’importance alimentaire, E. faecalis, S. aureus, E. coli, P. aeruginosa et C. albicans. L’influence de deux méthodes d’extraction et l’influence d’un solvant comme stabilisateur d’extraits de plante dans les milieux de culture aqueux ainsi que le rôle de la provenance de deux différents spécimens de E. olida ont été étudiés sur les activités antimicrobiennes. Le profile des extraits de plante ainsi que les composés majeurs ont été analysés par GC/MS. Résultats Les huiles essentielles des quatre espèces d’Eucalyptus ont montré un degré variable d’activités antimicrobiennes contre le panel de micro-organismes testé, l’huile essentielle de E staigeriana montrant le meilleur potentiel. Les extraits d’hexane n’ont montré qu’une faible voir aucune activité antimicrobienne, excepté contre S. aureus. P. aeruginosa s’est montré comme le micro-organisme le plus résistant et S. aureus comme le plus faible. L’effet du solvant a montré une diminution de l’activité des extraits de plante ou bien n’a aucune influence. Les analyses GC/MS ont montré des huiles essentielles riches en composés très volatils pour E. dives ainsi que E. staigeriana et des composés plus lourds pour les deux spécimens de E. olida. Objectives This study was undertaken to screen the in vitro antimicrobial properties of four Ausralian native Eucalyptus species, i.e., E. dives, E. gunnii, E. olida and E. staigeriana against five food-related micro-organisms, i.e., E. faecalis, S. aureus, E. coli, P. aeruginosa and C. albicans. The influences of two different extraction methods as well as the influence of a surfactant as plant extract dissolver in the water-based culture media used in agar disc diffusion tests and the role of growth location of two different E. olida specimens were investigated on the antimicrobial activity. Plant extracts profile and major compounds were analysed by GC/MS. Results Essential oils of the four Eucalyptus species displayed a variable degree of antimicrobial activity against the panel of micro-organisms tested, E. staigeriana oil showing a greater potential. Hexane extracts displayed no or low antimicrobial properties against the microbial strains tested with the exception of S. aureus. P. aeruginosa proved to be the most resistent micro-organism tested while S. aureus was the most sensitive one. The effect of a surfactant showed to decrease the antimicrobial activity of plant extracts or to not have any influence at all. GC/MS analyses showed that E. staigeriana and E. dives essential oils contain mostly volatile compounds while essential oils of both E. olida specimens contain heavier compounds. Ziele Diese Studie wurde durchgeführt um die antimikrobiologischen Eigenschaften von vier einheimischen australischen Eukalyptus Arten zu untersuchen. Es wurden die Eigenschaften von E. dives, E. gunnii, E. olida und E. staigeriana gegenüber fünf in der Lebensmitteltechnologie wichtigen Mikroorganismen, das heisst, E. faecalis, S. aureus, E. coli, P. aeruginosa und C. albicans getestet. Der Einfluss zweier unterschiedlicher Extraktionsmethoden und der Herkunft zweier unterschiedlicher E olida Spezies sowie der Einfluss eines Lösungsmittels, welches die Diffusion im Kulturmilieu erleichtert, auf die antimikrobiologischen Eigenschaften wurde untersucht. Das Profil der Pflanzenextrakte sowie die Hauptkomponenten wurden mittels GC/MS analysiert. Resultate Die ätherischen Öle der vier Eukalyptus Arten zeigten unterschiedliche antimikrobiologische Aktivität gegenüber den Versuchsmikroorganismen. Das ätherische Öl von E. staigeriana wies das grösste Potential auf. Die Hexan-Extrakte zeigten nur schwache bis keine antimikrobiologischen Eigenschaften ausser gegenüber S. aureus. P. aeruginosa stellte sich als resistentester Mikroorganismus heraus und S. aureus als der schwächste. Der Einsatz des Lösungsmittels hatte entweder keinen Einfluss oder führte zu einer Abnahme der antimikrobiologischen Aktivität der Pflanzenextrakte. GC/MS Analysen zeigten, dass die ätherischen Öle von E. staigeriana and E. dives hauptsächlich aus flüchtigen Verbindungen bestanden während die ätherischen Öle der beiden E. olida Arten schwerere Verbindungen enthielten.

Mass-sensitive electro-acoustic devices such as surface acoustic wave (SAW) micro-balances, capable to operate with aqueous media are particularly favorable for the development of biosensors. Their dimensions and physical properties offer a large potential in biological fluid investigations, especially for measuring physical phenomenon (mass deposition, adsorption, pressure…). In this work, we propose a specific grating configuration to lower the influence of viscosity of fluids which reduces the signal dynamics of the surface wave transducers. A dedicated liquid cell also has been developed to isolate the electro-active part of the device. The fabrication of the cell is achieved using theSU-8™ photo-resist, allowing for manufacturing thick structures preventing any contact between the tested liquids and the transducers. Furthermore, the sensing area has been optimized to optimize the sensor gravimetric sensitivity. The operation of the sensor is illustrated by detecting bovine serum albumin (BSA) adsorption in the sensing area.

International audience; This paper reports the realization of a 5 MHz frequency difference x10 pre-multiplier, developed in the laboratory to replace an obsolete one. The principle we chose is to synthesize a 45 MHz and a 50 MHz from a reference signal and from the signal to be measured, and to subtract one to the other to generate a 5 MHz, whose precision on the measurement is increased by a factor 10. Obtained Allan variance Σy(Τ) at 1 s is 5.10-14 and output spectral density of phase noise floor is about -160 dBc/Hz at 5 MHz.