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In this paper physicochemical properties of non-doped GaN 0.94 As 0.06 (0001) are presented and compared to the host material. The GaN(As) epitaxial layers were grown by molecular beam epitaxy (MBE) using an As-cracker source and studied in situ in an interconnected analytical chamber using X-ray photoelectron spectroscopy (XPS). The results achieved for the highly ordered (1 × 1), (0001)-oriented GaN(As) samples reveal changes in binding energy (BE) positions of the Ga-3d and N-1s core-level lines compared to the GaN template. These peaks are shifted by about 0.4 eV towards a lower BE and positions of As states correspond to the As-Ga bonds. The valence band (VB) shape of GaN(As) indicates the same features as the host material in the range of higher BEs, however notable changes occur in the vicinity of the Fermi level. The VB maximum of GaN(As) is considerably shifted upwards. • The highly ordered (1 × 1), (0001)-oriented, non-doped GaN 0.94 As 0.06 was grown by MBE method. • The Ga-3d and N-1s peaks for the GaN(As) are shifted by 0.4 eV towards a lower binding energy (BE) vs. the pure GaN. • The positions of BE for As states correspond to As-Ga bonds. • In the valence band (VB) of the GaN(As) notable changes occur in the vicinity of the Fermi level. • The VB maximum of the GaN(As) is significantly shifted towards the Fermi level and is located at a BE of 1.0 eV. [ABSTRACT FROM AUTHOR]

In this work, we present three groups of microcavities: based on selenium compounds only, based on tellurium compounds only, and structures based on mixed selenium and tellurium compounds. We focus on their possible applications in the field of optoelectronic devices and fundamental physics (VCSELs, narrow range light sources, studies of cavity-polariton electrodynamics) in a range of wavelength from 540 to 760 nm. [ABSTRACT FROM AUTHOR]

Background Women in labour are considered at risk of gastric content aspiration partly because the stomach remains full before delivery. Ultrasonographic measurement of antral cross-sectional area (CSA) is a validated method of gastric content assessment. Our aim was to determine gastric content volume and its changes in parturients during labour under epidural analgesia using bedside ultrasonography. Methods The cut-off value corresponding to an increased gastric content was determined by ultrasound measurement of antral CSA in six pregnant women in late pregnancy before and after ingestion of 250 ml of non-clear liquid. Antral CSA was then measured twice in 60 parturients who presented in spontaneous labour: when the anaesthesiologist was called for epidural analgesia catheter placement, and at full cervical dilatation. Patient-controlled epidural analgesia was performed with a solution of ropivacaine and sufentanil. Results After liquid ingestion, antral CSA (mm2) increased from 90 (range, 80–151) to 409 (range, 317–463). A CSA of 320 was taken as cut-off value. The feasibility rate of antral CSA determination was 96%. CSA decreased from 319 [Q1 158–Q3 469] to 203 [Q1 123–Q3 261] during labour (P=2×10−7). CSA was >320 in 50% of parturients at the beginning of labour vs 13% at full cervical dilatation (P=0.006). Conclusions Bedside ultrasonographic antral CSA measurement is feasible in pregnant women during labour and easy to perform. The observed decrease in antral CSA during labour suggests that gastric motility is preserved under epidural anaesthesia. The procedure could be used to assess individual risk of gastric content aspiration during labour. [ABSTRACT FROM PUBLISHER]

Abstract: This work presents methods of controlling the density of self-assembled CdTe quantum dots (QDs) grown by molecular beam epitaxy. Two approaches are discussed: increasing the deposition temperature of CdTe and the reduction of CdTe layer thickness. Photoluminescence (PL) measurements at low temperature confirm that both methods can be used for significant reduction of QDs density from 1010 QD/cm2 to 107–108 QD/cm2. For very low QDs density, identification of all QDs lines observed in the spectrum is possible. [Copyright &y& Elsevier]

Abstract: We present the realization and characterization of a 20-fold, fully lattice-matched epitaxial distributed Bragg reflector based on (Cd,Zn)Te and (Cd,Zn,Mg)Te layers. We also present a microcavity based on (Cd,Zn,Mg)Te containing a (Cd,Zn)Te quantum well. Reflectivity spectra, photoluminescence imaging in real space and in far field are presented. [Copyright &y& Elsevier]

Objectives: To study the role and indications of breast MRI in normal breast screening. Patients and methods: Retrospective study of 51 patients (mean age of 51 years) conducted in northern Finistère. Each patient had a normal (BI-RADS 1 or 2) breast screening (mammography and echography). Four indications for MRI were chosen: screening of high-risk patients, high-density breasts, radio-clinical discordance, and breasts prostheses. Breast MRI were reviewed according to BI-RADS classification. Abnormalities categorized in BI-RADS 4 or 5 were confirmed histologically. Results: Thirteen patients underwent histological analysis. Nine invasive carcinomas were identified (six invasive lobular carcinomas (ILC), two mixed carcinomas, one invasive ductal carcinoma). For these patients, the reason for performing MRI was a radio-clinical discordance. Discussion and conclusion: The study demonstrates the breast MRI value for radio-clinical discordance and the key role of MRI in diagnostic challenge of ILC. In literature review, MRI has a role even if breast screening is normal: radio-clinical discordance, screening of patients with high-risk, breasts prostheses in certain cases. Breast density comes as an additional criteria to perform this exam. [Copyright &y& Elsevier]

Abstract: Introduction. – To the request of total plasma homocysteine determination in the investigation of vascular disease, diagnosis of homocystinuria in young adult patients with mild phenotype is not so rare. Exegesis. – A 26-year-old man developed embolic cerebral infarction and a 22-year-old woman presented a right renal venous thrombosis one week after delivery. In each case, high concentration of total plasma homocysteine was first found and plasma and urinary amino acids analysis later on directed the diagnosis towards homocystinuria. Finally, reduced skin fibroblast cystathionine β-synthase activity confirmed the diagnosis of homocystinuria. Conclusion. – Total plasma homocysteine determination must be determined for screening for hyperhomocysteinemia in young adults with venous thromboembolism without characteristic phenotypic features of homocystinuria. [Copyright &y& Elsevier]

Copyright of EMC-Radiologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of EMC-Chirurgie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction L’administration intraveineuse continue de lidocaïne en périopératoire améliore l’analgésie post-opératoire [1] . Cependant, l’effet anesthésique peropératoire de la lidocaïne est mal connu. Certaines études ont suggéré qu’elle pouvait diminuer les besoins anesthésiques peropératoires [2] . L’objectif de ce travail est d’évaluer l’influence de la lidocaïne sur l’administration automatisée du propofol et du rémifentanil guidée par l’index bispectral (BIS), excluant toute interférence de l’investigateur. Matériel et méthodes Il s’agit d’une étude prospective multicentrique en double aveugle. Après accord du comité d’éthique et consentement écrit, des patients admis pour chirurgie réglée gynécologique ou urologique ont été randomisés dans deux groupes (lidocaïne versus placebo). La lidocaïne était administrée sous la forme d’un bolus de 1,5 mg.kg −1 en 10 min avant l’induction suivi d’une perfusion continue de 2 mg.kg −1 .h −1 jusqu’à la fin de l’anesthésie. Le groupe placebo recevait un bolus puis une perfusion continue de sérum physiologique. Les agents anesthésiques, propofol et rémifentanil, étaient administrés par la boucle d’asservissement [3] qui permet une adaptation automatisée de leurs posologies en maintenant le BIS entre 40 et 60. Résultats Soixante-trois patients comparables sur le plan démographique et statut ASA ont été inclus. L’âge moyen dans les deux groupes était de 43 ans avec plus de 92 % de sexe féminin. Quatre-vingt-treize pour cent des interventions chirurgicales étaient gynécologiques et 53 % par voie laparoscopique. Il n’y avait pas de différence de durée d’intervention et de profondeur de l’anesthésie entre les deux groupes. Les doses de propofol et de rémifentanil à l’induction et durant l’entretien sont comparables entre les deux groupes ( Tableau 1 ). Discussion La titration automatisée des agents anesthésiques guidée par le BIS est une méthode non-biaisée pour évaluer les consommations. Il reste possible que le BIS ne prenne pas en compte l’action de la lidocaïne et que les besoins en agents anesthésiques n’en soient pas affectés de ce fait par la chirurgie réputée peu douloureuse [3] . [ABSTRACT FROM AUTHOR]

This work is devoted to epitaxy and magnetooptical study of (Zn,Co)Te and (Cd,Co)Te dilute magnetic semiconductors. Giant Zeeman effect is observed in both reflectivity and photoluminescence measurements. Magnetoreflectivity is used to determine cobalt composition. Magnetophotoluminescence reveals quenching due to intra-ionic cobalt transitions. The quenching is more effective at zero magnetic field than at high magnetic field, and in (Cd,Co)Te comparing to (Zn,Co)Te. [ABSTRACT FROM AUTHOR]

This article addresses the main results of the PEPS (PEllet Photonic Sensor) project, whcich aims at developing a new gas sensing transducer via a technological breakthrough: the combination of photonics (insensitive to external electromagnetic disturbances) and catalysis (reversibility, limited energy consumption). Indeed, catalytic reactions are often exothermic and this heat can modify the properties of optical devices. The experimental studies performed during the PEPS project highlighted the rapid and reversible response at room temperature of catalytic powders towards different concentrations of H 2 in air. The thermal and optical properties of the materials used for the integrated photonic component have also been studied. These results have been exploited for the design of the photonic transducers. The feasibility of the physical transduction principle has been demonstrated by developing different prototypes based on Bragg gratings and Multimode Interference Components. [ABSTRACT FROM AUTHOR]

We report on the technological and optical investigations of quantum dots (QDs) formation with magnetic ions, in particular QDs with single manganese ions. Motivation of our study was to control the ion-exciton interaction by controlling the position of a magnetic ion in a QD. We used molecular beam epitaxy (MBE) of CdTe/ZnTe QDs (zinc blend structure) and we studied the impact of the position of Mn δ-doping in the CdTe layer on their optical properties. The position of Mn δ-doping affects emission spectra of individual QDs with single magnetic ions and properties of QDs ensemble such as QDs density or photoluminescence energy. [ABSTRACT FROM AUTHOR]

Abstract: The LePix project explores monolithic pixel sensors fabricated in a 90nm CMOS technology built over a lightly doped substrate. This approach keeps the advantages usually offered by Monolithic Active Pixel Sensors (MAPS), like a low input capacitance, having a single piece detector and using a standard CMOS production line, and adds the benefit of charge collection by drift from a depleted region several tens of microns deep into the substrate, therefore providing an excellent signal to noise ratio and a radiation tolerance superior to conventional un-depleted MAPS. Such sensors are expected to offer significant cost savings and reduction of power consumption for the same performance, leading to the use of much less material in the detector (less cooling and less copper), addressing one of the main limitations of present day particle tracking systems. The latest evolution of the project uses detectors thinned down to 50μm to obtain back illuminated sensors operated in full depletion mode. By back-processing the chip and collecting the charge from the full substrate it is hence possible to efficiently detect soft X-rays up to 10keV. Test results from first successfully processed detectors will be presented and discussed. [Copyright &y& Elsevier]

Abstract: The LePix projects aim realizing a new generation monolithic pixel detectors with improved performances at lesser cost with respect to both current state of the art monolithic and hybrid pixel sensors. The detector is built in a 90nm CMOS process on a substrate of moderate resistivity. This allows charge collection by drift while maintaining the other advantages usually offered by MAPS, like having a single piece detector and using a standard CMOS production line. The collection by drift mechanism, coupled to the low capacitance design of the collecting node made possible by the monolithic approach, provides an excellent signal to noise ratio straight at the pixel cell together with a radiation tolerance far superior to conventional un-depleted MAPS. The excellent signal-to-noise performance is demonstrated by the device ability to separate the 6keV 55Fe double peak at room temperature. To achieve high granularity (10–20µm pitch pixels) over large detector areas maintaining high readout speed, a completely new compressing architecture has been devised. This architecture departs from the mainstream hybrid pixel sparsification approach, which uses in-pixel logic to reduce data, by using topological compression to minimize pixel area and power consumption. [Copyright &y& Elsevier]

Abstract: The LePix project aims at improving the radiation hardness and the readout speed of monolithic CMOS sensors through the use of standard CMOS technologies fabricated on high resistivity substrates. In this context, high resistivity means beyond , which is at least one order of magnitude greater than the typical value adopted for integrated circuit production. The possibility of employing these lightly doped substrates was offered by one foundry for an otherwise standard 90 nm CMOS process. In the paper, the case for such a development is first discussed. The sensor design is then described, along with the key challenges encountered in fabricating the detecting element in a very deep submicron process. Finally, irradiation results obtained on test matrices are reported. [Copyright &y& Elsevier]

Abstract: We present a monolithic pixel sensor developed in the framework of the LePIX project aimed at tracking/triggering tasks where high granularity, low power consumption, material budget, radiation hardness and production costs are a concern. The detector is built in a 90nm CMOS process on a substrate of moderate resistivity. This maintains the advantages usually offered by Monolithic Active Pixel Sensors (MAPS), like a low input capacitance, having a single piece detector and using a standard CMOS production line, but offers charge collection by drift from a depleted region and therefore an excellent signal to noise ratio and a radiation tolerance superior to conventional undepleted MAPS. Measurement results obtained with the first prototypes from laser, radioactive source and beam test experiments are described. The excellent signal-to-noise performance is demonstrated by the capability of the device to separate the peaks in the spectrum of a 55Fe source. We will also highlight the interaction between pixel cell design and architecture which points toward a very precise direction in the development of such depleted monolithic pixel devices for high energy physics. [Copyright &y& Elsevier]