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International audience; This article provides the reader a focused and organised review of the research progresses on neurophysiological indicators, also called “neurometrics”, to show how neurometrics could effectively address some of the most important Human Factors (HFs) needs in the Air Traffic Management (ATM) field. The state of the art on the most involved HFs and related cognitive processes (e.g. mental workload, cognitive training) is presented together with examples of possible applications in the current and future ATM scenarios, in order to better understand and highlight the available opportunities of such neuroscientific applications. Furthermore, the paper will discuss the potential enhancement that further research and development activities could bring to the efficiency and safety of the ATM service.

International audience; This paper proposes a new test approach that goes beyond cell-aware test: device-aware test. The approach consists of three steps: defect modeling, fault modeling, and test/DfT development. The defect modeling does not assume that a defect in a device (or a cell) can be modeled electrically as a linear resistor (as the traditional approach suggests), but it rather incorporates and captures the impact of the physical defect on the technology parameters of the device and thereafter on its electrical parameters. Once the defective electrical model is defined, a systematic fault analysis (based on fault simulation) is performed to derive appropriate fault models and thereafter test solutions. The approach is demonstrated using two memory technologies: resistive random access memory (RRAM) and spintransfer torque magnetic random access memory (STT-MRAM). The results show that the proposed approach is able to sensitize faults for defects that are not detected with the traditional approach, meaning that the latter cannot lead to high-quality test solutions as required for defective part per billion (DPPB) level. The new approach clearly sets up a turning point in testing at least for the considered two emerging memory technologies.

International audience; The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received 12 million s funding under the European Union Framework Programme 7 from 1st June 2008 to 30th November 2012. The 19 project partners from both academia and industry from in total 7 countries had a project budget of 16 Ms with which they have discovered, created and developed a huge body of insights into nucleic acid analysis. Results have been presented widely in publications and in innumerous public presentations. Results have been moved to spin-offs such as the Olink enrichment kits (now sold by Agilent as Haloplex) and are findingtheir way to the market, such as the Oxford Nanopore MinIon sequencer that was first released to early-access user sites in 2014.

International audience; Metal-elastomer interfacial systems, often encountered in stretchable electronics, demonstrate remarkably high interface fracture toughness values. Evidently, a large gap exists between the rather small adhesion energy levels at the microscopic scale (‘intrinsic adhesion’) and the large measured macroscopic work-of-separation. This energy gap is closed here by unravelling the underlying dissipative mechanisms through a systematic numerical/experimental multi-scale approach. This self-containing contribution collects and reviews previously published results and addresses the remaining open questions by providing new and independent results obtained from an alternative experimental set-up. In particular, the experimental studies on Cu-PDMS (Poly(dimethylsiloxane)) samples conclusively reveal the essential role of fibrillation mechanisms at the micro-meter scale during the metal-elastomer delamination process. The micro-scale numerical analyses on single and multiple fibrils show that the dynamic release of the stored elastic energy by multiple fibril fracture, including the interaction with the adjacent deforming bulk PDMS and its highly nonlinear behaviour, provide a mechanistic understanding of the high work-of-separation. An experimentally validated quantitative relation between the macroscopic work-of-separation and peel front height is established from the simulation results. Finally, it is shown that a micro-mechanically motivated shape of the traction-separation law in cohesive zone models is essential to describe the delamination process in fibrillating metal-elastomer systems in a physically meaningful way.

International audience; High values for the work of separation have been reported in peel tests on fibrillating interfacial systems. The exact origin of these high values is not properly understood, since it remains unclear which dissipative mechanisms related to fibrillation cause a significant increase in the work of separation. In this paper, the contribution of fibril mechanics to the work of separation is quantified. To this end, a micromechanical model of a single fibril is used, in which the growth of a nucleated fibril up to the moment of fracture is described. The initial geometry is varied to reflect the variability in the substrate profile. It is observed that the stresses and strains that occur in the model are well beyond typical bulk values. Given the large variation in measured stress–strain curves for rubber materials reported in literature, a small scale single fibril experiment is performed to assess the applicability of reported bulk material parameters to this problem. The obtained experimental response falls well within the model bandwidth for the range of material parameters from literature. Furthermore, the fibril fracture stress, which serves as the failure criterion in the model, is extracted from the experiment. From the micromechanical model results, it appears that, for the considered range of material properties, the work of separation is mainly influenced by the fracture stress. Furthermore the initial geometry has a profound influence on the obtained work of separation. It is concluded that the work of separation determined from the micro-model is significantly larger than the intrinsic adhesion energy, yet it remains still an order of magnitude smaller than the values reported in literature. For the considered system this indicates that, although it has a significant contribution, fibril deformation is not the only contribution to the high work of separation.

International audience; Fixation density maps (FDM) created from eye tracking experiments are widely used in image processing applications. The FDM are assumed to be reliable ground truths of human visual attention and as such one expects high similarity between FDM created in different laboratories. So far, no studies have analysed the degree of similarity between FDM from independent laboratories and the related impact on the applications. In this paper, we perform a thorough comparison of FDM from three independently conducted eye tracking experiments. We focus on the effect of presentation time and image content and evaluate the impact of the FDM differences on three applications: visual saliency modelling, image quality assessment, and image retargeting. It is shown that the FDM are very similar and that their impact on the applications is low. The individual experiment comparisons, however, are found to be significantly different, showing that inter-laboratory differences strongly depend on the experimental conditions of the laboratories. The FDM are publicly available to the research community.

International audience; Medial skeletons provide an effective alternative to boundary or volumetric representations for applications that focus on shape structure. This capability is provided by the skeletal structure, i.e., the curves and surfaces computed from centers of maximally inscribed balls by a process called structuration. Many several structuration methods exist, all having various challenges in terms of delivering a high-quality medial skeleton. This paper provides a first overview of existing structuration methods. We formally define the skeletal structure by giving its theoretical properties, and use these properties to propose quality criteria for structurations. We next review existing structuration methods and compare them using the established criteria. The obtained insights help both practitioners in choosing a suitable structuration method and researchers in further perfecting such methods.

International audience; The loss of cardiac pump function accounts for a significant increase in both mortality and morbidity in Western society, where there is currently a one in four lifetime risk, and costs associated with acute and long-term hospital treatments are accelerating. The significance of cardiac disease has motivated the application of state-of-the-art clinical imaging techniques and functional signal analysis to aid diagnosis and clinical planning. Measurements of cardiac function currently provide high-resolution datasets for characterizing cardiac patients. However, the clinical practice of using population-based metrics derived from separate image or signal-based datasets often indicates contradictory treatments plans owing to inter-individual variability in pathophysiology. To address this issue, the goal of our work, demonstrated in this study through four specific clinical applications, is to integrate multiple types of functional data into a consistent framework using multi-scale computational modelling.

International audience; Interface delamination in metal–rubber-type stretchable electronic systems leads to early failure. This paper reports an investigation of metal–rubber interfaces through in situ scanning electron microscopy imaging of the progressing delamination front of 90° peel tests of rubber on copper samples. The results show that the energy dissipated in the forming, elongation and rupture of ∼50 μm long fibrils constitutes the major part of the work of separation. The experiments are characterized and modeled using a cohesive zone-enriched finite-element model.

International audience; We studied millimeter-sized aqueous sessile drops in an ambient oil environment in a classical electrowetting configuration with a wire-shaped electrode placed at a variable height above the substrate. Within a certain range of height and above a certain threshold voltage, the drop oscillates periodically between two morphologies where it is either attached to the wire or detached from it. We determine the range of control parameters, wire height, and voltage in which oscillations occur and explain it by a simple capillary model. Furthermore, we analyze the dynamics of the oscillations using high-speed video microscopy and numerical fluid dynamics modeling. We develop a one-dimensional harmonic oscillator model that describes the dependence of the drop oscillations on the relevant intrinsic (surface tension, viscosity, density) and extrinsic (wire height, voltage) parameters.

International audience; Knowledge of left atrial (LA) anatomy is important for atrial fibrillation ablation guidance, fibrosis quantification and biophysical modelling. Segmentation of the LA from Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) images is a complex problem. This manuscript presents a benchmark to evaluate algorithms that address LA segmentation. The datasets, ground truth and evaluation code have been made publicly available through the http://www.cardiacatlas.org website. This manuscript also reports the results of the Left Atrial Segmentation Challenge (LASC) carried out at the STACOM'13 workshop, in conjunction with MICCAI'13. Thirty CT and 30 MRI datasets were provided to participants for segmentation. Each participant segmented the LA including a short part of the LA appendage trunk and proximal sections of the pulmonary veins (PVs). We present results for nine algorithms for CT and eight algorithms for MRI. Results showed that methodologies combining statistical models with region growing approaches were the most appropriate to handle the proposed task. The ground truth and automatic segmentations were standardised to reduce the influence of inconsistently defined regions (e.g., mitral plane, PVs end points, LA appendage). This standardisation framework, which is a contribution of this work, can be used to label and further analyse anatomical regions of the LA. By performing the standardisation directly on the left atrial surface, we can process multiple input data, including meshes exported from different electroanatomical mapping systems

International audience; Remarkable toughnesses have been reported for metal–elastomer interfaces in stretchable electronics and attributed to surface roughness-induced fibrillation. Interestingly, this micro-mechanism was also observed for PDMS, known for its hyperelastic and thus non-dissipative material behavior. Here, the energy dissipation origin is elucidated by a thorough multi-scale experimental analysis of PDMS-copper delamination, for two distinct mode-mixities and surface roughnesses. The fracture process zone was observed by in situ and post-mortem optical and electron microscopy, and compared to cohesive-zone finite elements simulations: The PDMS deformation is indeed (predominantly) reversible and most energy is dissipated by release of elastically stored energy upon fibril fracture.

International audience; A remarkable high fracture toughness is sometimes observed for interfaces between materials with a large elastic mismatch, which is reported to be caused by the fibrillar microstructure appearing in the fracture process zone. In this work, this fibrillation mechanism is investigated further to investigate how this mechanism is dissipating energy. For that purpose, thermoplastic urethane (TPU)-copper interfaces are delaminated at various rates in a peel test experimental setup. The fracture process zone is visualized in situ at the meso-scale using optical microscopy and at the micro-scale using Environmental Scanning Electron Microscopy (ESEM). It is shown that the geometry of the fracture process zone is insensitive to the delamination rate, while the interface traction scales logarithmically with the rate. This research has revealed that, the interface roughness is shown to be pivotal in initiating the fibrillation delamination process, which facilitates the high fracture toughness. The multi-scale experimental approach identified two mechanisms responsible for this high fracture toughness. Namely, the viscous dissipation of the TPU at the high strain levels occurring in the fibrils and the loss of stored elastic energy which is disjointed from the propagation due to the size of the process zone.

The effect of the oil/water interfacial tension on the voltage-controlled two-dimensional motion of an oil/water interface across a hydrophobic fluoropolymer insulator is investigated within an electrowetting-based optical element. The investigated element is a pixel that contains dyed oil and water. The concentration and type of dye used to color the oil phase has been varied. The resulting changes in the oil/water interfacial tension have been evaluated together with the dynamics and electro-optic characteristics of an open pixel. Experimental results are correlated with the measured static oil/water interfacial tension values. When decreasing the oil/water interfacial tension, the amplitude of the driving voltage required for obtaining a given oil displacement decreases and the switching curve becomes more steep. These effects can be accurately reproduced by means of an electro-optic model. Moreover, a reduction in oil/water interfacial tension strongly affects the speed of the moving oil/water interface. It accelerates the voltage driven oil contraction and decelerates the oil film reformation process that results upon removal of the voltage. The contact-line speed of the oil droplet depends linearly on the electrowetting driving force defined by the oil/water interfacial tension and the contact angle as a function of time. In case the horizontally expanding oil film meets a vertical hydrophilic wall an additional term has to be included in the electrowetting driving force to account for pinning effects. This term does not depend on the oil/water interfacial tension. Reported results provide useful directions when formulating dyed oils for electrowetting-based devices with moving oil/water interfaces.

International audience; Purpose: Reconstruction of the beating heart in 3D + time in the catheter laboratory using only the available C-arm system would improve diagnosis, guidance, device sizing, and outcome control for intracardiac interventions, e.g., electrophysiology, valvular disease treatment, structural or congenital heart disease. To obtain such a reconstruction, the patient's electrocardiogram (ECG) must be recorded during the acquisition and used in the reconstruction. In this paper, the authors present a 4D reconstruction method aiming to reconstruct the heart from a single sweep 10 s acquisition.Method: The authors introduce the 4D RecOnstructiOn using Spatial and TEmporal Regularization (short 4D ROOSTER) method, which reconstructs all cardiac phases at once, as a 3D + time volume. The algorithm alternates between a reconstruction step based on conjugate gradient and four regularization steps: enforcing positivity, averaging along time outside a motion mask that contains the heart and vessels, 3D spatial total variation minimization, and 1D temporal total variation minimization.Results: 4D ROOSTER recovers the different temporal representations of a moving Shepp and Logan phantom, and outperforms both ECG-gated simultaneous algebraic reconstruction technique and prior image constrained compressed sensing on a clinical case. It generates 3D + time reconstructions with sharp edges which can be used, for example, to estimate the patient's left ventricular ejection fraction.Conclusions: 4D ROOSTER can be applied for human cardiac C-arm CT, and potentially in other dynamic tomography areas. It can easily be adapted to other problems as regularization is decoupled from projection and back projection.Acknowledgement: Published by the American Association of Physicists in Medicine. The electronic version of this work can be reached by using the following link: http://dx.doi.org/10.1118/1.4860215

International audience; The anatomy and motion of the heart and the aorta are essential for patient-specific simulations of cardiac electrophysiology, wall mechanics and hemodynamics. Within the European integrated project euHeart, algorithms have been developed that allow to efficiently generate patient-specific anatomical models from medical images from multiple imaging modalities. These models, for instance, account for myocardial deformation, cardiac wall motion, and patient-specific tissue information like myocardial scar location. Furthermore, integration of algorithms for anatomy extraction and physiological simulations has been brought forward. Physiological simulations are linked closer to anatomical models by encoding tissue properties, like the muscle fibers, into segmentation meshes. Biophysical constraints are also utilized in combination with image analysis to assess tissue properties. Both examples show directions of how physiological simulations could provide new challenges and stimuli for image analysis research in the future.

Metal-oxide polymer diodes exhibit non-volatile resistive switching. The current–voltage characteristics have been studied as a function of temperature. The low-conductance state follows a thermally activated behaviour. The high-conductance state shows a multistep-like behaviour and below 300 K an enormous positive temperature coefficient. This anomalous behaviour contradicts the widely held view that switching is due to filaments that are formed reversibly by the diffusion of metal atoms. Instead, these findings together with small-signal impedance measurements indicate that creation and annihilation of filaments is controlled by filling of shallow traps localized in the oxide or at the oxide/polymer interface.

International audience; We present a computational model of a thalamocortical relay neuron for exploring basal ganglia thalamocortical loop behavior in relation to Parkinson's disease and deep brain stimulation (DBS). Previous microelectrode, single-unit recording studies demonstrated that oscillatory interaction within and between basal ganglia nuclei is very often accompanied by synchronization at Parkinsonian rest tremor frequencies (3–10 Hz). These oscillations have a profound influence on thalamic projections and impair the thalamic relaying of cortical input by generating rebound action potentials. Our model describes convergent inhibitory input received from basal ganglia by the thalamocortical cells based on characteristics of normal activity, and/or low-frequency oscillations (activity associated with Parkinson's disease). In addition to simulated input, we also used microelectrode recordings as inputs for the model. In the resting state, and without additional sensorimotor input, pathological rebound activity is generated for even mild Parkinsonian input. We have found a specific stimulation window of amplitudes and frequencies for periodic input, which corresponds to high-frequency DBS, and which also suppresses rebound activity for mild and even more prominent Parkinsonian input. When low-frequency pathological rebound activity disables the thalamocortical cell's ability to relay excitatory cortical input, a stimulation signal with parameter settings corresponding to our stimulation window can restore the thalamocortical cell's relay functionality.

A generic process has been developed to grow nearly defect free arrays of (heterostructured) InP and GaP nanowires. Soft nanoimprint lithography has been used to pattern gold particle arrays on full 2 inch substrates. After lift-off organic residues remain on the surface, which induce the growth of additional undesired nanowires. We show that cleaning of the samples before growth with piranha solution in combination with a thermal anneal at 550 C for InP and 700 C for GaP results in uniform nanowire arrays with 1% variation in nanowire length, and without undesired extra nanowires. Our chemical cleaning procedure is applicable to other lithographic techniques such as e-beam lithography, and therefore represents a generic process., 12 pages, 4 figures, 2 tables

International audience; We present an optical biosensor technology that integrates the tethered particle motion technique and the magnetic tweezer technique. The goal is to quantify the three-dimensional mobility of bound particle labels and to characterize the bond between the particle and the surface. We show using a series of four different lengths of dsDNA (105 bp to 590 bp) that plots of the height as function of the in-plane particle position reflect the bond length and bond flexibility. We analyze ensembles of bound particles and show that the height displacement is at maximum the bond length, but that non-specific sticking causes large variations between particles. We also measured the height of bound particles under influence of magnetic forces. A magnetic gradient force towards the surface brought particles on average closer to the surface, but a magnetic gradient force away from the surface did not bring all particles away from the surface. We show that the latter can be explained by magnetic anisotropy in the particles. Our results demonstrate that mobility detection of bound particle labels in an evanescent field is a promising technique to characterize the bond between a particle and a surface in a biosensor system.

International audience; We demonstrate in this paper that the effect of object shift in an elliptical, astigmatic Gaussian beam does not affect the optimal fractional orders used to reconstruct the holographic image of a particle or another opaque object in the field. Simulations and experimental results are presented.

6 páginas, 10 figuras., This paper reports a new built-in self-test scheme for analog and mixed-signal devices based on die-level process monitoring. The objective of this test is not to replace traditional specification-based tests, but to provide a reliable method for early identification of excessive process parameter variations in production tests that allows quickly discarding of the faulty circuits. Additionally, the possibility of on-chip process deviation monitoring provides valuable information, which is used to guide the test and to allow the estimation of selected performance figures. The information obtained through guiding and monitoring process variations is re-used and supplement the circuit calibration.

International audience; During the last half century, a dramatic downscaling of electronics has taken place, a miniaturization that the industry expects to continue for at least a decade. We present efforts to use the self-assembly of one-dimensional semiconductor nanowires1 in order to bring new, high-performance nanowire devices as an add-on to mainstream Si technology. The nanowire approach offers a coaxial gate-dielectric-channel geometry that is ideal for further downscaling and electrostatic control, as well as heterostructure-based devices on Si wafers.

International audience; THERMINIC Workshops are a series of events to discuss the essential thermal questions of microelectronic microstructures and electronic parts in general. These questions are becoming more and more crucial with the increasing element density of circuits packaged together and with the move to nanotechnology. These trends are calling for thermal simulation, monitoring and cooling. Thermal management is expected to become an increasingly dominating factor of a system's cost. The growing power dissipated in a package, the mobile parts of microsystems raise new thermal problems to be solved in the near future necessitating the regular discussion of the experts in these fields. Finally, there is an increasing need for accurate assessment of the boundary conditions used in the analysis of electronic parts, which requires a concurrent solution of the thermal behaviour of the whole system.

Submitted on behalf of EDAA (http://www.edaa.com/); International audience; Both the number of embedded memories, as well as the total embedded memory content in our chips is growing steadily. Time for chip designers, EDA makers, and test engineers to update their knowledge on memories. This Hot Topic paper provides an embedded tutorial on embedded memories, in terms of what is new and coming versus what is old and vanishing, and what are the associated design, test, and repair challenges related to using embedded memories.

Editorial; Medical & Biological Engineering & Computing; International audience; Heart disease represents a highly relevant and epidemio- logically significant contributor to loss of quality and quantity of life. In Europe, cardiovascular disease (CVD) causes nearly half of all deaths or 4.3 million deaths a year [1]. CVD manifests itself in diseases such as coronary artery disease, congestive heart failure, and cardiac arrhythmias. These diseases have a significant impact on the EU economy with an estimated cost of EUR 192 billion a year [1]. This significant financial burden is spread across community sectors with approximately 57 % of costs due to direct health care costs, 21 % due to productivity losses and 22 % due to the informal care of people with CVD. Thus, the early detection and prediction of the progression of CVD are key requirements toward improved treatment, a reduction in mortality and morbidity, and of course to reduce healthcare costs...

We have studied the optical transitions in artificial atoms consisting of one to ten electrons occupying the conduction levels in ZnO nanocrystals. We analyzed near IR absorption spectra of assemblies of weakly coupled ZnO nanocrystals for a gradually increasing electron number and found four allowed dipole transitions with oscillator strengths in quantitative agreement with tight-binding theory. Furthermore, this spectroscopy provides the single-particle energy separation between the conduction levels of the ZnO quantum dots.

International audience; THERMINIC Workshops are a series of events to discuss the essential thermal questions of microelectronic microstructures and electronic parts in general. These questions are becoming more and more crucial with the increasing element density of deep submicron downscaling of integrated circuits necessitating thermal simulation, monitoring and cooling. Thermal management is expected to become an increasingly dominating factor of a system's cost. The high element density of MCMs, the growing power dissipated in a package, etc., and the mobile parts of microsystems raise new thermal problems to be solved in the near future necessitating the regular discussion of the experts in these fields. Finally, there is an increasing need for accurate assessment of the boundary conditions used in the analysis of electronic parts, which requires a concurrent solution of the thermal behaviour of the whole system.

International audience; Particle labels are used in biosensors to detect the presence and concentration of analyte molecules. In this paper we demonstrate an optical technique to measure the mobility and height of bound particle labels on a biosensor surface with single-label resolution. The technique is based on the detection of the particle-induced light scattering in an optical evanescent field. We show that the thermal particle motion in the evanescent optical field leads to intensity fluctuations that can accurately be detected. The technique is demonstrated using 290 bp (99 nm) DNA as an analyte, and using polystyrene particles and magnetic particles with diameters between 500 nm and 1000 nm as labels. The particle intensity histograms show that quantitative height measurements are obtained for particles with uniform optical properties, and the intensity versus position plots reflect the analyte-antibody orientation and the analyte flexibility. The novel optical detection technique will lead to biosensors with very high sensitivity and specificity.

Model representations of varying complexity are used to describe the band structure of semiconductor quantum wells and superlattices. However, the physics of valence-band-confined states is usually restricted to the upper ${\mathrm{\ensuremath{\Gamma}}}_{8}^{\mathit{v}}$ band. We report spectroscopic measurements of the light- to heavy-hole splitting in (Ga,In)As-AlAs strained multiple quantum wells. The results are compared to two types of theoretical calculations: (i) within the framework of the usual approximations, and (ii) taking account of the ${\mathrm{\ensuremath{\Gamma}}}_{7}^{\mathit{v}}$ split-off states, which are mixed with the light-hole ones. We demonstrate the crucial influence of the valence-band coupling, by a significant improvement of the agreement between theory and experiments. Competitive effects of thicknesses, potential-well depths, and magnitude of the ${\mathrm{\ensuremath{\Gamma}}}_{8}^{\mathit{v}\mathrm{\ensuremath{-}}}$${\mathrm{\ensuremath{\Gamma}}}_{7}^{\mathit{v}}$ splitting are detailed and discussed.

This article was corrected/updated to include the complete graphic legend of Fig. 3.