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International audience; In this paper, the performance of different hybrid navigation filters exploiting GPS, Galileo and 5G Time Of Arrival (TOA) measurements in multipath environment are studied. For the realism of the study, realistic propagation channels must be considered and their impacts on the received signals processing must be accurately modelled. GNSS signal mathematical models in multipath environment have been analyzed for a long time. However, 5G mathematical models in a realistic multipath environment are still in its early stages of analysis. This article is divided in three main parts. The first part is dedicated to the identification of compliant GNSS and 5G signal propagation channel models; SCHUN is selected for GNSS and QuaDRiGa is selected for 5G. Based on this, the correlator output mathematical models for 5G signals and GNSS signals are derived. The second part tackles the accurate characterization of the pseudo range errors due to propagation channels shadowing and multipath effect as well as thermal noise. This step is required for the correct derivation of the navigation filters. Indeed, the study will focus on Extended Kalman Filters (EKF) and Unscented Kalman Filters (UKF); both assume a Gaussian distribution of the errors. Therefore, by optimally characterizing the errors, the performances of the filters are expected to be improved. The last part consists in validating through simulations the theory and mathematical models developed in the first and second parts.

International audience; This article offers a new characterization of GNSS meaconing and its impact on GNSS receivers through mathematical modelsand simulations.First, general mathematical models of the received signal at a receiver’s correlators input and output in nominal conditions thenin presence of a GNSS repeater are derivated. Then, the impact of a GNSS repeater is mathematically determined throughsimulations on a virtual GNSS receiver having various trajectories (static, pedestrian, car and airborne) for both realistic anddegraded satellites and repeater configurations.In this article, the received meaconing power, code delay and phase shift are computed with reason to the authentic signal’sparameters. A 3D multipath error envelope is introduced to obtain maximal and minimal code delay estimation error accordingto multipath’s delay and Doppler difference. A model of the newCN0cause by the meaconer is also given in this article.Simulations in nominal and degraded satellites configurations for various trajectories allow to emphasize the impact of themeaconer’s Doppler difference on the pseudorange and positioning errors. The impact of meaconing also is also proven togreatly depends on the GNSS receiver’s trajectory and velocity

Summary Background Patients with COVID-19 who develop severe acute respiratory distress syndrome (ARDS) can have symptoms that rapidly evolve to profound hypoxaemia and death. The efficacy of extracorporeal membrane oxygenation (ECMO) for patients with severe ARDS in the context of COVID-19 is unclear. We aimed to establish the clinical characteristics and outcomes of patients with respiratory failure and COVID-19 treated with ECMO. Methods This retrospective cohort study was done in the Paris–Sorbonne University Hospital Network, comprising five intensive care units (ICUs) and included patients who received ECMO for COVID-19 associated ARDS. Patient demographics and daily pre-ECMO and on-ECMO data and outcomes were collected. Possible outcomes over time were categorised into four different states (states 1–4): on ECMO, in the ICU and weaned off ECMO, alive and out of ICU, or death. Daily probabilities of occupation in each state and of transitions between these states until day 90 post-ECMO onset were estimated with use of a multi-state Cox model stratified for each possible transition. Follow-up was right-censored on July 10, 2020. Findings From March 8 to May 2, 2020, 492 patients with COVID-19 were treated in our ICUs. Complete day-60 follow-up was available for 83 patients (median age 49 [IQR 41–56] years and 61 [73%] men) who received ECMO. Pre-ECMO, 78 (94%) patients had been prone-positioned; their median driving pressure was 18 (IQR 16–21) cm H2O and PaO2/FiO2 was 60 (54–68) mm Hg. At 60 days post-ECMO initiation, the estimated probabilities of occupation in each state were 6% (95% CI 3–14) for state 1, 18% (11–28) for state 2, 45% (35–56) for state 3, and 31% (22–42) for state 4. 35 (42%) patients had major bleeding and four (5%) had a haemorrhagic stroke. 30 patients died. Interpretation The estimated 60-day survival of ECMO-rescued patients with COVID-19 was similar to that of studies published in the past 2 years on ECMO for severe ARDS. If another COVID-19 outbreak occurs, ECMO should be considered for patients developing refractory respiratory failure despite optimised care. Funding None.

The most ancient rocks in the geological record provide insights into the processes that shaped the evolution and composition of the first continental masses. Due to both the scarcity and the polymetamorphic history of exposed Eoarchean (>3.5 Ga) crust, the study of early geodynamic processes is very challenging and most of our knowledge has been learned from only a few localities on Earth.The present study focuses on felsic meta-igneous rock from the Saglek Block (North Atlantic Craton), a locality where recent zircon U-Pb dating studies indicate earliest crust formation in the Eoarchean (Komiya et al., 2017; Sałacińska et al., 2018; Vezinet et al., 2018). We performed in situ oxygen isotopes measurement (SIMS analyses) in zircon grains that have been carefully selected from CL-imaging for the good preservation of their internal structure and for their pristine composition in rare Earth element. We then performed U-Pb/Hf isotopes by laser ablation split stream (LASS)-ICP-MS. The results indicate 3 distinct crystallization events: (1) an Eoarchean event at ca 3.86 Ga; (2) an early Paleoarchean metamorphic event at ca. 3.5 Ga, and (3) a Neoarchean event (ca. 2.7-2.8 Ga) with zircon domains showing complex zoned overgrowths. While the 3.86 Ga magmatic domains display mantle-like δ18O(+4.9±0.2‰ to +6.8.0±0.2‰, n=30), large O-isotope fractionation (δ18Ovalues up to +9‰) characterise the Paleoarchean metamorphic event. Such elevated δ18O signatures provide unequivocal evidence for hydrosphere–crust interactions and reworking processes resulting in metamorphic zircon growth at ca. 3.5 Ga, namely 1 Ga before the Archean-Proterozoic transition (Vezinet et al., 2019).Interestingly, the two oldest age groups have chondritic to sub-chondritic εHfi values: +1.0 ± 2.2 to –5.5 ± 1.8 whereas large variations in Hf isotope composition (εHfi value from –11.2 ± 2.5 to –20.3 ± 1.5) are found in the 2.8–2.7 Ga zircon domains. Such intra-sample heterogeneities implies a significant perturbation of Hf-isotope composition during metamorphic events related to mixing of fluid with inherited (older) Hf isotope source. In the light of these results, we will discuss the potential consequences of isotope perturbation on whole-rock isochrones interpretation. Komiya, T., et al. "A prolonged granitoid formation in Saglek Block, Labrador: Zonal growth and crustal reworking of continental crust in the Eoarchean." Geoscience Frontiers 8.2 (2017): 355-385.Sałacińska, A., et al. "Complexity of the early Archean Uivak Gneiss: Insights from Tigigakyuk Inlet, Saglek Block, Labrador, Canada and possible correlations with south West Greenland." Precambrian Res. 315 (2018): 103-119.Vezinet, A, et al. "Hydrothermally-altered mafic crust as source for early Earth TTG: Pb/Hf/O isotope and trace element evidence in zircon from TTG of the Eoarchean Saglek Block, N. Labrador. EPSL 503 (2018): 95-107.Vezinet, A., et al. "Extreme δ18O signatures in zircon from the Saglek Block (North Atlantic Craton) document reworking of mature supracrustal rocks as early as 3.5 Ga." Geology 47.7 (2019): 605-608.

The first lower hybrid current drive experiments in the full tungsten WEST tokamak are reported. Good wave coupling is found at rather low plasma current (q95∼4.3) and medium density (ne∼3×1019m-3). Reflection coefficient is in agreement with the expectation from the linear theory of coupling. With low reflection coefficients, 5MW was coupled for 2 seconds. High central electron temperature, up to 5keV, is achieved at ne = 3-4×1019m-3. Flat and even hollow profiles of tungsten density are derived from the bolometry diagnostic. The stored thermal energy follows the H96-P scaling law with very slight degradation with density. The current drive efficiency has been assessed in low loop voltage (VL∼0.15V) discharges. Low plasma current operation and rather high effective charge (Zeff∼3) lead to modest current drive efficiency (ƞ = 0.5-0.65 × 1019 A.W−1m-2). Long pulse operation (∼30s) with high LHCD power (PLH=2.7MW) is achieved with stationary parameters, in particular electron and impurity densities, with the upper water-cooled tungsten divertor.

Repetitive high-voltage square pulses are of great importance for producing long-pulse electron beams and high-power microwaves. One of possible technologies for the generation of such pulses is a Marx generator using pulse forming network (PFN) stages, often combined with a pulse sharpening technique to reduce the rise time to a few nanoseconds (peaking stage). This paper presents an innovative design, named the “zigzag design,” for the optimization of the compactness and of the rise time of 400-kV–85-ns PFN-Marx. Thanks to this design, the 16 stages of this generator, which delivers an open circuit output voltage of 720 kV, fit in a 650-mm length. For a slightly overmatched load ( $Z_{\mathrm {load}} = 100 ~\Omega$ ), the output voltage reaches 400 kV with a rise time as less as 5 ns. The inductance reduction associated with the innovative zigzag design, which allows this sharp rise time with no need for a peaking stage, is described. The 85-ns plateau duration of the pulse is given by the PFN construction of each stage, which is based on six ceramic capacitors (2.1 nF–45 kV) connected within a strip line. The 16 PFN stages are housed in a 360-mm diameter gas pressurized vessel. Burst mode operation for a duration of 10 s at a pulse repetition frequency of 100 Hz is reported, for a resistive load and for the electron beam diode of a X-band relativistic backward-wave oscillator (BWO). To reach further compactness, the BWO system is integrated on side of the generator vessel and a U-shaped gas pressurized line connects both systems through a compact conical vacuum insulator.

Objectives Nebulized colistimethate sodium (CMS) can be used to treat ventilator-associated pneumonia caused by MDR bacteria. The influence of the diluent volume of CMS on aerosol delivery has never been studied. The main objectives of the study were to compare aerosol particle characteristics and plasma and urine pharmacokinetics between two diluent volumes in patients treated with nebulized CMS. Methods A crossover study was conducted in eight patients receiving nebulized CMS every 8 h. After inclusion, nebulization started with 4 million international units (MIU) of CMS diluted either in 6 mL (experimental dilution) or in 12 mL (recommended dilution) of normal saline in a random order. For each diluent volume, CMS aerosol particle sizes were measured and plasma and urine samples were collected every 2 h. Nebulization time and stability of colistin in normal saline were assessed. Results The mass median aerodynamic diameters were 1.4 ± 0.2 versus 0.9 ± 0.2 μm (P

Summary Background Prediction of neurological outcome after cardiac arrest is a major challenge. The aim of this study was to assess whether quantitative whole-brain white matter fractional anisotropy (WWM-FA) measured by diffusion tensor imaging between day 7 and day 28 after cardiac arrest can predict long-term neurological outcome. Methods This prospective, observational, cohort study (part of the MRI-COMA study) was done in 14 centres in France, Italy, and Belgium. We enrolled patients aged 18 years or older who had been unconscious for at least 7 days after cardiac arrest into the derivation cohort. The following year, we recruited the validation cohort on the same basis. We also recruited a minimum of five healthy volunteers at each centre for the normalisation procedure. WWM-FA values were compared with standard criteria for unfavourable outcome, conventional MRI sequences (fluid-attenuated inversion recovery and diffusion-weighted imaging), and proton magnetic resonance spectroscopy. The primary outcome was the best achieved Glasgow-Pittsburgh Cerebral Performance Categories (CPC) at 6 months, dichotomised as favourable (CPC 1–2) and unfavourable outcome (CPC 3–5). Prognostication performance was assessed by the area under the receiver operating characteristic (ROC) curves and compared between groups. This study was registered with ClinicalTrials.gov, number NCT00577954. Findings Between Oct 1, 2006, and June 30, 2014, 185 patients were enrolled in the derivation cohort, of whom 150 had an interpretable multimodal MRI and were included in the analysis. 33 (22%) patients had a favourable neurological outcome at 6 months. Prognostic accuracy, as quantified by the area under the ROC curve, was significantly higher with the normalised WWM-FA value (area under the ROC curve 0·95, 95% CI 0·91–0·98) than with the standard criteria for unfavourable outcome or other MRI sequences. In a subsequent validation cohort of 50 patients (enrolled between April 1, 2015, and March 31, 2016), a normalised WWM-FA value lower than 0·91, set from the derivation cohort, had a negative predictive value of 71·4% (95% CI 41·9–91·6) and a positive predictive value of 100% (90·0–100), with 89·7% sensitivity (75·8–97·1) and 100% specificity (69·1–100) for the prediction of unfavourable outcome. Interpretation In patients who are unconscious 7 days after cardiac arrest, the normalised WWM-FA value, measured by diffusion tensor imaging, could be used to accurately predict neurological outcome at 6 months. This evidence requires confirmation from future large-scale trials with a strict protocol of withdrawal or limitation-of-care decisions and time window for MRI. Funding French Ministry of Health, French National Agency for Research, Italian Ministry of Health, and Regione Lombardia.

Emission lines which appear in the spectral ranges of ground state transitions from n = 2 levels in He- and H-like argon ions are discussed. X-ray transitions from elements commonly found in tokamaks (tungsten, molybdenum, iron and sulphur) which radiate in the wavelength range from 3700–4000 mÅ are identified by comparison with atomic structure calculations. Individual lines from tungsten charge states in the vicinity of Zn-like W44+ are documented, along with B-like Mo37+. The behaviour of line ratios as a function of electron temperature is examined, in support of the identifications.

Differentiation of the continental crust is the result of complex interactions between a large number of processes, which govern partial melting of the deep crust, magma formation and segregation, and magma ascent to significantly higher crustal levels. The anatectic metasedimentary rocks exposed in the Southern Marginal Zone of the Limpopo Belt represent an unusually well-exposed natural laboratory where the portion of these processes that operate in the deep crust can be directly investigated in the field. The formation of these migmatites occurred via absent incongruent melting reactions involving biotite, which produced cm- to m-scale, K2O-poor garnet-bearing stromatic leucosomes, with high Ca/Na ratios relative to their source rocks. Field investigation combined with geochemical analyses, and phase equilibrium modelling designed to investigate some aspects of disequilibrium partial melting, show that the outcrop features and compositions of the leucosomes suggest several steps in their evolution: (1) Melting of a portion of the source, with restricted plagioclase availability due to kinetic controls, to produce a magma (melt + entrained peritectic minerals in variable proportions relative to melt); (2) Segregation of the magma at near peak metamorphic conditions into melt accumulation sites (MAS), a.k.a. future leucosome; (3a) Reequilibration of the magma with a portion of the bounding mafic residuum via chemical diffusion (H2O, K2O), which triggers the co-precipitation of quartz and plagioclase in the MAS; (3b) Extraction of melt dominated magma to higher crustal levels, leaving peritectic minerals entrained from the site of the melting reaction and the minerals precipitated in the MASs to form the leucosome in the source. The key mechanism controlling this behaviour is the kinetically induced restriction of the amount of plagioclase available to the melting reaction. This results in elevated melt H2O and K2O and chemical potential gradient for these components across the leucosome/mafic residuum contact. The combination of all of these processes accurately explains the composition of the K2O-poor leucosomes. These findings have important implications for our understanding of melt segregation in the lower crust and minimum melt residency time which, according to the chemical modelling is < 5 years. We demonstrate that in some migmatitic granulites, the leucosomes constitute a type of felsic refractory residuum, rather than evidence of failed magma extraction. This provides a new insight into the ways that source heterogeneity may control anatexis. This article is protected by copyright. All rights reserved.

The ITER bolometer diagnostic shall provide the measurement of the total radiation emitted from the plasma, a part of the overall energy balance. 550 lines-of-sight (LOS) will be installed in ITER observing the whole plasma from many different angles to enable reliable measurements and tomographic reconstructions of the spatially resolved radiation profile. The LOS are bundled in 71 individual cameras, which will be located behind blanket modules on the vacuum vessel wall, in five divertor cassettes, in two upper port plugs and in one equatorial port plug. For all major design issues solutions have been elaborated and will be presented. The design of collimators has been developed and tested on prototypes to provide an exact definition of the required viewing cones of about 1° while reliably reducing reflections, stray light and microwave stray radiation. A 3D-shaped ceramic printed circuit board is proposed to hold the sensor, orient it as desired, and provide good thermal contact as well as the bridge for electrically connecting external signal cables to the meanders on the sensor. The design of the camera housing for vacuum vessel and divertor cameras has been optimised for improved management of the thermal heat flow, supported by tests defining material properties and verifying analysis. Additionally, methods have been developed to derive the main design parameters of cameras and decide if pinhole or collimator type is more advantageous. Recently, the system-level design phase started and uses the achieved results to define interfaces and designs for the specific locations in ITER, with a focus on the vacuum-vessel cameras to finalise the interface with blanket modules.

International audience; High power electromagnetic signals can disrupt the functioning of electronic devices. As electromagnetism plays a role in cells homeostasis, such electromagnetic signals could potentially also alter some physiological processes. Herein we report on distinct biological parameters assessment after cellular spheroids exposure to high power electromagnetic signals, such as the ones used for defense applications. Signals effects were assessed in tumor cells spheroids and in normal human dermal fibroblasts spheroids, where macroscopic aspect, growth, plasma membrane integrity, induction of apoptosis, ATP content, and mitochondrial potential were investigated after spheroids exposure to high power electromagnetic signals. No significant effects were observed, indicating that 1.5 GHz narrowband electromagnetic fields with incident amplitude level of 40 kV/m, and 150 MHz moderate-band electric fields with an amplitude of 72.5 to approximately 200 kV/m, do not cause any significant alterations of assessed parameters. Electronic devices can stop operating in response to intense external electromagnetic signals. Electromagnetic environments, or more precisely intentional electromagnetic environments 1 , are among emerging approaches that could be used for defense applications. High power electromagnetic (HPEM) technology can be deployed to temporarily or permanently disrupt electronic devices or could even be used against the personnel 2. The HPEM systems that can be used to impair or destroy electronics and hardware 3 , and thus to black out the opponents electronic systems, operate in the range of tens of MHz to a few tens of GHz. Alternatively, HPEM signals (with frequencies of approximately 100 GHz and millimeter waves) could be used against personnel. This non-lethal directed-energy weapon, can heat the surface of its targets (e.g. heat people's skin) 2. Such non-lethal weapon system, also known as the Active Denial System, was developed by the U.S. military (https://jnlwp.defense. gov/Press-Room/Fact-Sheets/ArticleViewFactsheets/Article/577989/active-denial-technology-fact-sheet/ retrieved August 2018) and was designed for area denial, perimeter security and crowd control. Similar systems were also elaborated by Russia (https://www.popularmechanics.com/military/weapons/a7804/ why-russia-will-be-the-first-to-use-the-pain-ray-9833954/ retrieved August 2018) and China (http://en.people. cn/n3/2018/0205/c90000-9423875.html retrieved August 2018). High Power Microwave (HPM) and High Power Radio Frequency (HPRF) systems can radiate high power and short duration oscillatory pulses of electromagnetic fields. These pulses can exhibit different amplitudes, durations, frequency spectrums, as well as Pulse Repetition Frequencies (PRF), and can be classified into different families, according to their frequency spectrum bandwidth. The bandwidth classification distinguishes the narrowband (also known as hypo band), meso (or moderate) band, ultra-moderate (or sub-hyper) band and hyperband intentional electromagnetic environments 2 .

The Pietersburg Block (PB), the northernmost terrane of the Kaapvaal Craton, can be subdivided into four Archaean grey gneiss units: Makhutswi-Murchison South (MMS), Groot Letaba-Duivelskloof (GDL), Goudplaats-Hout River (GHR) and Southern Marginal Zone (SMZ). These domains are limited by greenstone belts (Pietersburg, Murchison, Rhenosterkoppies and Giyani) and major shear zones. These lithologies were intruded by a mafic-layered intrusion (the Rooiwater Complex) and voluminous syn- to post-tectonic granitoids forming either small bodies in grey gneisses or voluminous plutons/batholiths. The grey gneisses are made up of Mesoarchaean (3.12–2.85 Ga) and seldom Palaeoarchaean (3.46–3.17 Ga) TTGs formed by melting of metabasaltic rocks at >45 km depth. The greenstone belts consist of Palaeoarchaean (3.46–3.20 Ga) mafic metabasalts, metakomatiites (and intrusive counterparts) and rare Mesoarchaean (2.95–2.84 Ga) felsic volcanics, intercalated with BIF, chert and siliciclastic rocks deposited at 3.05–2.92 Ga in the Murchison belt; 2.88–2.80 Ga in the Pietersburg and Giyani belts; and 2.76–2.71 Ga in the Rhenosterkoppies belt and SMZ. All lithologies were affected by greenschist—to upper amphibolite-facies metamorphism, mainly during Mesoarchaean N–S-directed compression. The 2.97–2.96 Ga Rooiwater Complex and coeval felsic volcanics of the Murchison belt formed through fractionation of mantle-derived magma. Granitoids of the PB include Bt-(Ms-) granites formed at 2.84–2.75 Ga by melting of TTGs (± sediments), and Hbl-Bt-(Cpx-)sanukitoids and Bt-Ep-granitoids at 2.70–2.67 Ga by melting of enriched lithospheric mantle and interactions with the crust during magma ascent. After formation of a Palaeoarchaean (3.46–3.18 Ga) micro-terrane(s) in an island arc and/or oceanic plateau setting, the geodynamic evolution of the PB features a Meso- to Neoarchaean (3.15–2.65 Ga) accretionary orogen formed during protracted southward subduction. The Mesoarchaean evolution began at 3.15–2.97 Ga with the formation of an arc/back-arc system along the northern margin of the proto-Kaapvaal Craton. Subsequently, it was controlled by the docking of the Palaeoarchaean micro-terrane at 2.97–2.84 Ga, causing intense crustal reworking in an Andean-type continental margin setting (2.84–2.73 Ga) and by Neoarchaean (2.73–2.65 Ga) continent-continent collision with a crustal block located farther North, possibly the precursor (>2.7 Ga) rocks of the Central Zone of the Limpopo Belt.

International audience; The use of GNSS in the railway sector has been postulated on the notion of a Virtual Balise (VB). The VB-based positioning system works by setting a VB point on the railway track and determining the passage of the VB point using the position solution from the GNSS receiver. Although augmentation systems such as SBAS or GBAS are able to satisfy the integrity requirements of the aviation standards down to the 10-7 level, it is difficult to satisfy the high integrity requirements of the railway sector because firstly the railway users located on the ground are affected by the ground environment such as terrain, buildings and tunnels and secondly because the stringency of the railway sector requirements extends below the 10-9 level. This paper proposes a method to detect faults in the GNSS solution due to satellite failure or local effects. Firstly, requirements for the monitoring performance are carefully derived accounting for the specificities of GNSS, namely that the possibility of consecutive VB faults cannot be discounted. The second contribution of the paper is the proposed detection using both odometry and track geometry of the onboard system. This enables to monitor all three-dimensional solution error so that higher sensitivity for the fault detection can be achieved. Simulations have been performed with both single and dual (GPS, GALILEO) solutions. It has been found that the combinations of metrics are able to achieve very small missed detection probabilities for mean failure rates from 5.0m/s down to 0.03m/s for most dual constellation geometries. The detection performance of the odometer implementation varied according to the heading of the train. On the other hand, when odometry and track geometry are used together, all the three-directional monitors can obtain stable results regardless of the heading.