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International audience; Langatate (LGT) crystals of La3Ga5.5Ta0·5O14 composition of diameter 50 mm were grown from the melt by Czochralski technique. Using (1–2 wt %) Ga2O3 excess in the starting charge and growing crystal in mixture argon (0.1–1%O2) gas atmosphere are a good condition to crystallize LGT under stationary stable regime. The LGT crystals grown along Z-axis exhibit strong faceting. The grown crystals were exempt of inclusions, cracks and secondary phases. The presence of oxygen in the growth chamber is necessary to limit gallium oxide evaporation and strongly affect the crystals coloration and the transmission spectra in the range (200–500 nm). The electrical resistivity is sensitive to the oxygen content in the growth environment.

Dysprosium-doped Ruddlesden−Popper calcium manganates with compositions of Ca2-xDyxMnO4 are potential candidates for high temperature thermoelectric applications. The effect of dysprosium doping on the crystal structure of Ca2-xDyxMnO4 at room temperature and its thermal behavior between RT and 800 °C were investigated in the range 0

In the time and frequency domain, we need ultrastable crystal resonators embedded in Ultra Stable Oscillators (USO), working at 10 MHz and exhibiting excellent short-term stabilities. Up to now, th...

The use of energy piles remains a topic of discussion in Belgian practice. The main concern is the lack of knowledge and documented experience with regard to the energy performance. Another issue is the potential impact of temperature changes and temperature cycles on the pile response (bearing capacity, settlements), in particular for piles with a relative small diameter. To address this challenge, an extensive full-scale test campaign on several types of energy piles has been set up. The energy piles are instrumented over their entire length with Fibre Bragg Grating (FBG) optical sensors and thermocouples. The tests aim at thermally characterizing the piles, as well as determining the combined thermo-mechanical behaviour. This paper presents an overview of the first, preliminary results of the test campaign and assesses the potential of a fully coupled analysis with the Finite Element Method (FEM) in Plaxis 2D software, showing a good agreement with the measurements.

International audience; La3Ga5,5Ta0,5O14 (LGT) langatate crystals were grown along Z-axis by Czochralski technique in argon and mixed argon with 0.1%O2 atmosphere. The coloration and the performance of langatate crystals were strongly connected to the starting chemical composition, the gas atmosphere and the growth parameters. Any deviation from the optimal LGT generate macroscopic defects such cracks and grains boundary causing a deterioration of the crystals performance.

Resume Objectifs Illustrer les aspects specifiques et non specifiques en imagerie standard, en imagerie en coupe (echographie, TDM et IRM) et en scintigraphie osseuse de la myosite ossifiante circonscrite (MOC). Patients et methodes Huit patients presentant une MOC (3 hommes et 5 femmes) ont ete explores par radiographies standards (8 cas), echographie (7 cas), scintigraphie (4 cas), TDM (6 cas) et IRM (4 cas). Resultat Les radiographies standard et l’echographie des parties molles ont montre dans 75 % des cas la presence d’une masse bien limitee contenant des calcifications. La TDM a pose le diagnostic de MOC dans 4 cas, en montrant des masses calcifiees separees de l’os adjacent par un lisere clair radio transparent ou des calcifications tumorales peripheriques centripetes tres suggestives de la MOC, L’IRM ete non specifique. La scintigraphie osseuse a montre une hyperfixation dans les 4 cas ou elle est realisee. Conclusion Les radiographies standard sont utiles pour demontrer les calcifications des MOC et pour preciser leur rapport avec l’os sous jacent. L’echographie et la scintigraphie osseuse sont interessantes dans le monitorage de la maturation lesionnelle. La TDM, en plus de la detection precoce des calcifications elle permet de localiser avec precision la lesion avant toute ablation chirurgicale. L’IRM est une technique tres sensible pour la detection de petite lesion a un stade precoce mais elle est non specifique ne permettant pas d’eviter la biopsie necessaire parfois pour eliminer une pathologie maligne.

Before using any piezoelectric crystal to realize acoustic devices (sensors, transducers, actuators or ultra-stable resonators) and beyond its mechanical properties, the crystal material itself has to be characterized. Whether the very interesting properties of the LGT crystal make it the best candidate to substitute quartz crystal for frequency output devices, we must take into account the crystal quality. Indeed, applications require homogeneous crystals with reproducible physical properties.

cited By 2; International audience; Among the crystals belonging to the langasite family, the Langatate (La3Ga5.5Ta0.5O14 also called LGT) seems to be the best candidate to substitute quartz crystal for acoustic waves applications and frequency output devices. But, its capability to substitute quartz depends on the crystalline quality of the production of the harvested boule. Indeed, the crystal quality (its homogeneity and its atomic structure as well as the amount of chemical impurities) can be very different from one supplier to another. So, to compare and analyze the strategic interest of this crystal, we start a sufficiently researched program, supported by the French DGA, to enable us to address the parameters of the growth process, implemented on Cristal Innov platform. The Langatate is an incongruent material grown from a ternary melt of La2O3 - Ga2O3 and Ta2O5 by the Czochralski technique along or in iridium crucible and slightly oxidizing atmosphere. Furthermore, a post-growth annealing was performed in the pulling machine immediately after growth and in other oven under vacuum or in oxidizing/reducing atmosphere. Post-growth annealing is necessary to remove the thermal stress induced by the growth that are revealed by shadowscopy and it will determine the color of the boule, which varies from colorless to orange or pale-green color. We attach to analyze the stoechiometry (i.e. the amount of the majors La, Ga, Ta) by Electron Probe Micro-Analysis (EPMA) and the impurities levels by femtosecond laser ablation Inductively Coupled Plasma Mass Spectrometry (fs LA-ICP-MS) of different LGT crystals from different suppliers. The presence of point defects and inhomogeneity of the crystal composition significantly affect the optical properties and can be also revealed by optical transmission spectra in UV-VIS and IR ranges. © 2014 IEEE.

Elastofibroma dorsi is a rare benign and slow growing fibro-proliferative lesion of unknown pathogenesis. It has a characteristic location (periscapular region) and a specific imaging appearance (songraphy, CT, MRI) allowing accurate prospective diagnosis. The recognition of this benign lesion avoids unnecessary biopsy and/or surgery. We report three cases of elastofibroma dorsi illustrating the characteristic features on sonography, CT and MRI. Involvement was bilateral in two cases.

Three cases of hydatid disease of the soft tissues are reported. All presented as soft tissue lesions in the neck and lower extremities. All three cases were studied with ultrasound (US) and magnetic resonance (MR) imaging techniques. Two patients presented with multivesicular lesions, which were considered diagnostic for hydatid disease. The third showed a lesion with hypoechoic solid and lobulated pattern mimicking lymph node. MR outlined the cystic pattern with intense peripheral enhancement and was suggestive of an infected cystic lesion. Surgery was performed in all three cases. Hydatid disease presenting in the soft tissues can be diagnosed with confidence, when US and/or MR shows multivesicular lesions. MR appears to be the most useful imaging technique when a complex or solid pattern is present. Enhancement of the peri-cystic soft tissues can be considered as a suggestive MR feature of soft tissue hydatid disease.

Resume Le syndrome de Macleod est une bronchopneumopathie obstructive liee aux sequelles anatomiques de bronchiolites aigues virales de l'enfance. Il est souvent asymptomatique et est de decouverte tardive chez l'adulte jeune. Nous rapportons un cas pediatrique associant rachitisme severe et poumon hyperclair chez qui la symptomatologie a ete particulierement grave avec une evolution defavorable.

The study represents a diagnostical analysis of the water use at a farm level, which is a necessary step in the development and implementation of strategies to improve the management of irrigation water at an irrigation district scale. The work has focused on a case study, namely the irrigated district of Cherfech located in the governorate of Ariana, 25 km away from Tunis. The analysis concerns 63 farms covering an area of 850 ha during the 2010-2011 crop season. The achievement of this analysis was made possible using the MABIA-REGION software. Thus, daily Penman-Monteith reference evapotranspiration (ET0), effective precipitation (PE), dual crop coefficients (Kc=Ke+Kcb), potential and actual crop evapotranspiration (ETc and ETa) and net and gross irrigation requirements (NIR and GIR) were estimated for the different study levels (plot, farm and district) using spatially distributed parameters on the climate, crop, soil characteristics, irrigation system, growing season and basic irrigation management practice. These different outputs were also spatially represented using the GIS-Mod tool implemented in MABIA-REGION. The results obtained show that the irrigation's practice was seasonally variable. Thus, during the winter season, the irrigations practiced was far exceeded the irrigation water requirement estimated by MABIA-Region. While during the summer season, the irrigations carried have merely covered 44% of irrigation water requirements. Also, the study reveals a high variability in the practice of irrigation between different cultures and different farms.

Post-traumatic carotid-cavernous fistula is an abnormal communication between the internal carotid artery in its intracavernous portion and the cavernous sinus, resulting from a tear in the arterial wall connecting the internal carotid artery with the cavernous sinus. Direct gunshot trauma is unusual. Clinically, the symptoms most often include a classic triad: red eye, chemosis and proptosis. Cross-sectional imaging including CT angiography allows for positive diagnosis by showing pathognomonic signs. Arteriography remains the procedure of choice for proper mapping of the lesion and accurate specification of the type of fistula, and at the same time serves as a means of embolization.

Illustrate the specific and nonspecific aspects of myositis ossificans circumscripta (MOC) in standard imaging, cross-sectional imaging (sonography, CT, and MRI), and bone scintigraphy.Eight patients presenting with MOC (three men and five women) were explored using standard radiography (eight cases), sonography (seven cases), scintigraphy (four cases), CT (six cases), and MRI (four cases).Standard x-rays and sonography of the soft tissue showed a well-defined mass containing calcifications in 75% of the cases. The CT scan diagnosed MOC in four cases, showing calcified masses separated from the adjacent bone by a clear radiotransparent border or afferent peripheral tumoral calcifications highly suggestive of MOC. MRI was nonspecific. Bone scintigraphy showed hyperfixation in the four cases imaged.Standard x-rays were useful to demonstrate the calcifications of MOC and to identify their relation with the subjacent bone. Sonography and bone scintigraphy were interesting in monitoring the lesion's maturation. In addition to early detection of calcifications, CT can precisely localize the lesion before surgical ablation. MRI is a very sensitive technique in detecting small lesions at an early stage, but it is nonspecific and does not remove the necessity of biopsy to eliminate the possibility of a malignant disease.

Resume Le diagnostic des ruptures de la coiffe s’est considerablement ameliore au cours des dernieres annees, grâce au progres des techniques d’imagerie qui demeurent performantes pour l’etablissement d’un bilan lesionnel precis. L’interet de notre travail est d’evaluer les performances diagnostiques de l’imagerie dans les lesions de la coiffe. Nous avons confronte dans notre etude, l’echographie et l’arthroscanner a la chirurgie et nos resultats ont montre de tres bonnes performances des deux techniques dans cette indication. On a etudie les differentes limites de ces deux techniques, et nous avons demontre la place de chaque technique dans la detection des differents types de lesion.

Elastofibroma dorsi is a rare benign and slow growing fibro-proliferative lesion of unknown pathogenesis. It has a characteristic location (periscapular region) and a specific imaging appearance (songraphy, CT, MRI) allowing accurate prospective diagnosis. The recognition of this benign lesion avoids unnecessary biopsy and/or surgery. We report three cases of elastofibroma dorsi illustrating the characteristic features on sonography, CT and MRI. Involvement was bilateral in two cases.

Three cases of hydatid disease of the soft tissues are reported. All presented as soft tissue lesions in the neck and lower extremities. All three cases were studied with ultrasound (US) and magnetic resonance (MR) imaging techniques. Two patients presented with multivesicular lesions, which were considered diagnostic for hydatid disease. The third showed a lesion with hypoechoic solid and lobulated pattern mimicking lymph node. MR outlined the cystic pattern with intense peripheral enhancement and was suggestive of an infected cystic lesion. Surgery was performed in all three cases. Hydatid disease presenting in the soft tissues can be diagnosed with confidence, when US and/or MR shows multivesicular lesions. MR appears to be the most useful imaging technique when a complex or solid pattern is present. Enhancement of the peri-cystic soft tissues can be considered as a suggestive MR feature of soft tissue hydatid disease.

Objectifs Preciser l’apport de l’imagerie dans la localisation mediastinale des pseudokystes du pancreas. Materiels et methodes Nous rapportons le cas d’un enfant de 12 ans qui consulte pour des douleurs abdominales avec des vomissements. Il a beneficie d’une echographie abdominale et d’un scanner. Le malade a ete traite par ponction percutanee scanoguidee. Resultats Les explorations radiologiques ont mis en evidence une volumineuse masse kystique cloisonnee prenant naissance au niveau du pancreas et se developpant vers le mediastin a travers le hiatus œsophagien arrivant jusqu’au niveau de la carene en rapport avec un pseudokyste du pancreas. La rupture de ces kystes est une complication rare. Elle peut se faire dans le tube digestif mais surtout dans la plevre et le peritoine. La rupture du kyste dans les bronches, comme dans le cas rapporte, n’a jamais ete rapportee dans la litterature a notre connaissance. Conclusion La localisation mediastinale du faux kyste du pancreas est grave et rare. Elle doit etre evoquee devant une masse kystique du mediastin.

Resume La fistule carotido-caverneuse (FCC) post-traumatique est une communication anormale entre l’artere carotide interne dans sa portion intracaverneuse et le sinus caverneux, resultant d’une dechirure dans la paroi arterielle connectant l’artere carotide interne au sinus caverneux. Le traumatisme direct par balle est exceptionnel. Sur le plan clinique, la symptomatologie est faite le plus souvent d’une triade classique : œil rouge, chemosis et exophtalmie. L’imagerie en coupe notamment l’angioscanner permet d’etablir le diagnostic positif en montrant une semiologie specifique. L’arteriographie demeure l’examen de choix pour une bonne cartographie lesionnelle en precisant de facon exacte le type de la fistule, et sert comme premier temps pour l’embolisation.

Objectifs Preciser la place de l’echographie du poignet dans le diagnostic positif du syndrome du canal carpien (SCC) en utilisant l’examen electrophysiologique (EMG) comme « Gold standard ». Materiels et methodes Une etude prospective de 20 patientes, chez qui le diagnostic du SCC a ete suspecte cliniquement. Toutes les patientes ont beneficie d’un EMG et d’une echographie du poignet, fait par le meme radiologue en ignorant les resultats de l’EMG, dans un troisieme temps. Les resultats de l’EMG et de l’echographie ont ete compares. Resultats L’augmentation de la surface du nerf median, le bombement du ligament annulaire du carpe ainsi qu’une tenosynovite des tendons flechisseurs sont des signes fortement suggestifs du SCC. Conclusion Le diagnostic du SCC est le plus souvent clinique. La confirmation est habituellement apportee par l’EMG. Les resultats de l’echographie semblent se correler le mieux aux signes electrophysiologiques.

Existing AC power systems, established more than a century ago, are increasingly challenged by DC technologies, enabled by significant advancements in the power electronics and related scientific fields. Three major application areas for DC transmission are established: transferring bulk power over long distances, interconnecting grids and connecting offshore wind. Medium and low voltage DC application become more appealing based on the improved controllability, more effective integration of renewable energy sources, higher power density and better compatibility with underground cables. Such technologies will be attractive for the Swiss energy transition as they might provide more effective solutions for the densification of power systems, the integration of converter-based renewable energy sources and pumped-storage plants. In order to achieve this, several research challenges, however, need to be overcome and standardization must further advance. Several academic partners from Switzerland contribute to these research problems in WP3: “Multi-Terminal AC-DC Grids and Power Electronics” within the SCCER FURIES. In this paper six major topics are presented: -“General overview of DC options” where present and future applications of DC technologies as wells as MVDC grids development issues are discussed. -“MMC-based MVDC converters” where a selection of modular multilevel converter as a platform in order to provide flexibility in addressing a multitude of applications and conversion needs is shown. Several topological adaptations are proposed, leading to novel converter topologies. -“AC/DC resonance analysis” where analysis allowing to find the resonance location and to analyzeres-onance nodes contribution to critical mode. These frequency analysis methods permit to foresee net-work frequency behavior that is becoming an important issue due to the growing number of power electronics converters in the network. -“Overview of HVDC breaker technologies” where basic requirements for fast and reliable HVDC circuit breakers as well as the differences to HVAC technology are introduced. -“HVDC circuit breakers: testing methods and challenges” where the limits of HVDC circuit breakers are explored. In this section, a flexible, modular high current source is presented. The source is intended to act as a hardware-in-the-loop test benchfor future HVDC circuit breakers, by driving highly dynamic and arbitrary current waveforms through dynamic loads (e.g. DC arc). -“Fault location principles” where the significant influence of fault location on the network security of supply and quality is drawn. A newly-developed technique which is based on the electromagnetic time reversal (EMTR) theory that can be applied to radial/meshed AC/DC power transmission or distribution networks is presented and compared to other Travelling Wave –based methods. The outputs and outlooks are drawn in order to conclude the paper.