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BACKGROUND Anti-CD38 therapy causes interference with both the direct and the indirect antiglobulin tests. We describe the experience from an Immunohematology Reference Laboratory and model cost options for providing safe transfusions. STUDY DESIGN AND METHODS Phenotyping, genotyping, and antibody identification orders were retrospectively reviewed in the setting of anti-CD38 therapy. The data were used to model the added cost of transfusion support. Four approaches were evaluated: 1) thiol-treated reagent red blood cells (RRCs) in antibody investigations with K– red blood cell (RBC) transfusions, 2) patient phenotyping or 3) genotyping with antigen-matched RBC transfusions, and 4) a combination of interval thiol-treated RRC antibody investigations with genotype antigen–matched RBC transfusions. RESULTS Sixty-two patients were identified as receiving anti-CD38 therapy. Thiol-treated RRC antibody investigations (28/62 patients) were favored over genotyping (23/62) and combination testing (11/62). Patient phenotyping failed to detect useful antigen information on eight patients: seven Fyb silencing mutations and one partial e. A thiol-treated RRC antibody investigation was the least expensive testing method for the first transfusion, but four- and five-antigen-matched RBC transfusions were equal in cost within five and 21 transfusion events, respectively. CONCLUSION Genotyping provided a more accurate antigen status than phenotyping patient RBCs. Patients requiring long-term transfusion support benefit from antigen matching when matching less than four antigens. Ultimately, the decision to genotype or use thiol-treated RRC antibody investigations will vary for each hospital blood bank.

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WOS:000587760800076; International audience; This article proposes a design procedure of an integrated air coil in a laminated bus bar for current sensing. The concept is based on an air coil inserted into the insulators inside the laminated bus bar, avoiding the use of intrusive current sensors with an additional stray inductance. First, the basic principle of the integrated current sensor is described, and the relationship between the mutual inductance and the structure of the air coil is discussed. Next, the frequency characteristic of the current sensor obtained based on an equivalent circuit is detailed, the parameters of which are derived from the sensor structure. A postprocessing method is proposed to achieve a 100-MHz frequency bandwidth. A prototype of the current sensor is designed based on the proposed design procedure, and the frequency characteristic is evaluated. The validations of the design procedure and the postprocessing method are confirmed experimentally.

Gallium nitride (GaN) transistors have demonstrated their potential as a high switching frequency, high power density, and high-efficiency power device. There has been substantial research undertaken on the switching and conduction losses calculation, where most studies have calculated them using an analytical approach. This paper presents an interpolation-based method to calculate switching and conduction losses. This interpolation method employs a combination of the GaN transistor and driving parameters such as parasitic capacitances, parasitic inductances, gate resistors, drain-to-source voltage, instantaneous current, and temperature. A value for switching loss is considered as a base value and the different combinations of circuits will be reached by using interpolated equations. The second aim of this study is to investigate the temperature-dependency of the ON state resistance: two values at different temperatures are considered and ON resistance will be obtained by linear interpolation. Finally, the accuracy of the proposed model is validated by using some scenarios on LTSPICE simulations.

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This paper proposes a gradient-based design optimization of multiphase inverter for electric vehicle application. The aim is to optimize the total volume of the converter taking account the number of phases, the sizing of dc-link capacitor and total surface of semi-conductors. The developed method shows that the optimum design is given for a number of phases more than three.

Understanding the temperature dependence of thermal boundary resistance, or Kapitza resistance, between liquid helium and sintered metal has posed a problem in low temperature physics for decades. In the ballistic regime of superfluid $^{3}$He-B, we find the Kapitza resistance can be described via scattering of thermal excitations (quasiparticles) with a macroscopic geometric area, rather than the sintered metal's microscopic area. We estimate that a quasiparticle needs on the order of 1000 collisions to successfully thermalise with the sinter. Finally, we find that the Kapitza resistance is approximately doubled with the addition of two mono-layers of solid $^{4}$He on the sinter surface, which we attribute to an extra magnetic channel of heat transfer being closed as the non-magnetic solid $^{4}$He replaces the magnetic solid $^{3}$He., Comment: 7 pages, 4 figures

WOS:000506165200071; International audience; Design optimization of magnetic components, which considers both electrical and thermal performance, can help in designing power converters with a high power density. This paper proposes an approximate analytical model for thermal resistance of inductor and transformer windings, including litz wire, which only requires knowledge of thermal properties of constituent materials and geometric dimensions. The model is based on regular square and hexagonal packing of insulatedwires and is derived by integration of infinitesimal thermal resistances along a specified heat flow path. The model closely agrees with finite-element analysis (FEA) and can be used in place of time-consuming FEA as part of larger thermal network models for magnetic components. The model is also experimentally validated using a toroidal inductor with a litz-wire winding; the model has less than 12% error compared to the experimental measurement. Application of the model for practical windings, including litz-wire windings, is also discussed. The model can be used during the design process of magnetic components of a switching power converter to evaluate the temperature and potential hot spots. The model provides closed-form results, hence fast computation times, and so can be used in design optimization procedures.

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Higher reliability and downsizing of the inverter circuit are the essential demands in electric vehicles. This paper proposes an overcurrent detection method in the inverter using an integrated Rogowski coil. Notably, the current detection which flows in power devices is vital for overcurrent protection when the switching fault occurs. The integrated Rogowski coil has been proposed as the switching waveform measurement. In this paper, the Rogowski coil is applied for the overcurrent detection for an electric vehicles inverter. This paper focuses on the overcurrent when the short circuit occurs on the switching leg, and the appropriate detection method using the Rogowski coil is determined and validated.

International audience; This paper describes the evolution of a powerelectronics class at Master level (second year), to comply withthe new trends of this science. Indeed, the switching speed ofpower semiconductor devices –especially wide bandgap devices–is continually increasing and, the knowledge and comprehensionof switching mechanisms is absolutely necessary to design powerconverters. Apart from theoretical lectures, several lab workshave been specifically developed, to use these devices at theirrated operating point. Five different themes are studied: devicecharacterization (bare dies), switching waveforms, lossescharacterization, thermal design, ElectroMagneticCompatibility and magnetics design.

The aim of the work described in this paper is to analyze the impact that converters interactions, in a power electronics embedded grid, have on the control performance of each subsystem, with particular focus on More Electric Aircraft (MEA) applications. The study has been carried out on a notional electrical system composed by two three-phase power converters – a Voltage Source Inverter (VSI) and an Active Front End (AFE) which are commonly used in More Electric Aircraft applications. The analysis has been conducted in order to show the necessity of using a global control design approach in such electrical systems, rather than on individual converters. The modelling approach and controller design are presented in the paper, supported by simulation and experimental validation.

International audience; This paper proposes an analytical computation of the rms current flowing in the input DC capacitor ofa PWM inverter. For a chosen PWM control, switching angles are computed in order to estimate thespectrum of the input current, which is the key design parameter of the input capacitor. The calculationtakes into account the AC current ripple, as it can be important, especially for interleaved inverters. Theimpact of the neutral connection between AC and DC side is also studied. The spectral repartition of thecurrent in the DC capacitor is shown and compared to simulation results. The impact of the AC currentripple, of the PWM generation and of the number of interleaved level is discussed.

Designing inductors in Power Electronics PWM inverter requires accounting for losses generated in these components, including saturation. This paper investigates the design of the AC output inductors of a PWM inverter. The induction waveform of the output inductor is first computed, taking into account a variable saturation state of the core. This enables to compute the core losses using iGSE in a particular analytical formulation. Furthermore a high frequency copper losses model applied to Litz wire is presented and validated using impedance measurement. A calorimetric method is used to measure and determine the area of validity of these core and copper losses models. With a calibration step, the global measurement error is below 0.2W. Over dozens of experiments carried out in different conditions, results show the importance of the choice of Steinmetz coefficients if the signal has multiple frequencies. The effect of the saturation on the waveform and on the losses is also depicted.

In this work, we present a multiperiod-optimization-based metric for grid resilience to a given contingency. This metric is computed from the solution of a multi-period optimal power flow problem and, as a byproduct, precomputes the optimal emergency generator response. Through numerical experiments we show that this metric improves with increased ramping capacity. With our StructJuMP/PIPS-NLP modeling and solver stack we demonstrate that, for networks up to 9241 buses this metric is computable in a time consistent with planning analyses, and for the 118 bus case, in a time compatible with a real time computation of optimal emergency generator response.

Superfluids, such as superfluid 3He and 4He, exhibit a broad range of quantum phenomena and excitations which are unique to these systems. Nanoscale mechanical resonators are sensitive and versatile force detectors with the ability to operate over many orders of magnitude in damping. Using nanomechanical-doubly clamped beams of extremely high-quality factors Q>106, we probe superfluid 4He from the superfluid transition temperature down to mK temperatures at frequencies up to 11.6 MHz. Our studies show that nanobeam damping is dominated by hydrodynamic viscosity of the normal component of 4He above 1K. In the temperature range 0.3-0.8K, the ballistic quasiparticles (phonons and rotons) determine the beams' behavior. At lower temperatures, damping saturates and is determined either by magnetomotive losses or acoustic emission into helium. It is remarkable that all these distinct regimes can be extracted with just a single device, despite damping changing over six orders of magnitude.

International audience; Superfluids, such as superfluid 3 He and 4 He, exhibit a broad range of quantum phenomena and excitations which are unique to these systems. Nanoscale mechanical resonators are sensitive and versatile force detectors with the ability to operate over many orders of magnitude in damping. Using nanomechanical-doubly clamped beams of extremely high quality factors (Q > 10 6), we probe superfluid 4 He from the superfluid transition temperature down to mK temperatures at frequencies up to 11.6 MHz. Our studies show that nanobeam damping is dominated by hydrodynamic viscosity of the normal component of 4 He above 1 K. In the temperature range 0.3 − 0.8 K, the ballistic quasiparticles (phonons and rotons) determine the beams' behavior. At lower temperatures, damping saturates and is determined either by magnetomotive losses or acoustic emission into helium. It is remarkable that all these distinct regimes can be extracted with just a single device, despite damping changing over six orders of magnitude.

Superfluids, such as superfluid $^3\mathrm{He}$ and $^4\mathrm{He}$, exhibit a broad range of quantum phenomena and excitations which are unique to these systems. Nanoscale mechanical resonators are sensitive and versatile force detectors with the ability to operate over many orders of magnitude in damping. Using nanomechanical-doubly clamped beams of extremely high quality factors ($Q>10^6$), we probe superfluid $^4\mathrm{He}$ from the superfluid transition temperature down to $\mathrm{mK}$ temperatures at frequencies up to $11.6 \, \mathrm{MHz}$. Our studies show that nanobeam damping is dominated by hydrodynamic viscosity of the normal component of $^4\mathrm{He}$ above $1\,\mathrm{K}$. In the temperature range $0.3-0.8\,\mathrm{K}$, the ballistic quasiparticles (phonons and rotons) determine the beams' behavior. At lower temperatures, damping saturates and is determined either by magnetomotive losses or acoustic emission into helium. It is remarkable that all these distinct regimes can be extracted with just a single device, despite damping changing over six orders of magnitude., 4 pages, 2 figures. arXiv admin note: text overlap with arXiv:1810.10129

Background MEGDHEL is an autosomal recessive syndrome defined as 3‐MEthylGlutaconic aciduria (3‐MGA) with Deafness, Hepatopathy, Encephalopathy, and Leigh‐like syndrome on magnetic resonance imaging, due to mutations in the SERAC1 (Serine Active Site Containing 1) gene, which plays a role in the mitochondrial cardiolipin metabolism. Methods We report the case of a young patient who presented with a convulsive encephalopathy, 3‐methylglutaconic aciduria, deafness, and bilateral T2 hypersignals of the putamen and the thalami, who passed away at 8 years of age. Results Analysis of nuclear genes using an ampliSeq™ targeted custom panel disclosed two compound heterozygous variants in the SERAC1 gene: a nonsense substitution in exon 4, c.202C>T, resulting in a premature stop codon (p.Arg68*), and a novel variant at a canonical splicing site upstream exon 4 (c.129‐1G>C). mRNAs sequencing from the fibroblasts of the patient showed that the splice site variant resulted in exon 3 skipping without frameshift while Western blot experiments showed the absence of SERAC1 expression compared to controls and abnormal filipin staining. Conclusion We showed that the loss of the putative transmembrane domain of SERAC1, due to a novel splice site variant, impairs the protein expression and is responsible for the MEGDHEL syndrome.

International audience; Cet article présente un outil d’optimisation destiné au dimensionnement d’onduleurs de forte puissance à base de transistor MOSFET en carbure de silicium. L’application concerne un cas d’étude aéronautique. Un outil d’optimisation déterministe est choisi car il est adapté au pré-dimensionnement des systèmes d’électronique de puissance avec de multiples contraintes. Différentes topologies d’onduleurs sont considérées avec leurs modèles associées. Parmi ces modèles, le dimensionnement des composants actifs et passifs, ainsi que le calcul harmonique des courants et tensions, sont développés. Des résultats d’optimisation sont enfin présentés avec comme objectif la minimisation de la masse globale du convertisseur. Les différentes topologies sont comparées pour définir laquelle est la plus adaptée au cahier des charges.

International audience; This paper presents a Bidirectional WirelessPower Transfer (BWPT) system, for medium speed chargingElectrical Vehicle (EV), with Vehicle to Grid (V2G) capability.The studied system has 20 kW power rating and allows an intercoildistance between 17 and 25 cm with an offset direction x andy of 10 cm. The control of the converters has also wirelessfeatures. Efficiency results of the whole DC-DC power structurewith the coupler are presented for several misalignments of thevehicle side. Finally, a way to improve the converters efficiencyis proposed, using a dedicated control allowing working in fullbridge synchronous rectifier mode, depending on the operating condition.

This paper presents a Bidirectional Wireless Power Transfer (BWPT) system, for medium speed charging Electrical Vehicle (EV), with Vehicle to Grid (V2G) capability. The studied system has 20 kW power rating and allows an inter-coil distance between 17 and 25 cm with an offset direction x and y of 10 cm. The control of the converters has also wireless features. Efficiency results of the whole DC-DC power structure with the coupler are presented for several misalignments of the vehicle side. Finally, a way to improve the converters efficiency is proposed, using a dedicated control allowing working in full bridge synchronous rectifier mode, depending on the operating condition.

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