The increase of the kidney diseases prevalence is a worldwide major public health issue due to the high cost of treatments at the end-stage kidney failure (dialysis or transplantation). It is so needed to better understand kidney physiological and physiopathological mechanisms, particularly those of the glomerular capillary wall that are involved in the first step of the blood filtration in order to develop new therapeutic strategies. This interdisciplinary research project aims to generate an innovative microfluidic platform reproducing the glomerular capillary wall to get further insight into its pathophysiology. Here, the goal is to address the following questions: can we model the glomerular capillary wall physiology and study in real time its modifications induced by membranous nephropathy and idiopathic nephrotic syndrome using this innovative platform? In order to answer this biomedical question, the microfluidic platform enable: (i) to generate a type IV collagen hydrogel-based membrane mimicking the glomerular basement membrane, (ii) to differentiate induced pluripotent stem cells into glomerular cells (podocytes and endothelial cells) and to culture them on each side of the hydrogel membrane and (iii) to integrate sensors with the associated instrumentation, which will allow to measure in real-time, by impedance spectroscopy, the physiopathological changes of the reconstructed glomerular capillary wall within the microfluidic platform.

The ETAE project suggests significant advancements about the emergence and control of hydrodynamic instabilities in closed recirculating flows with a free surface. This generic flow configuration is present in numerous industrial contexts. The present aim is, from well-designed excitations by electro-active actuators, to manipulate the flow, and thus to identify the mechanisms promoting large-scale vortical instabilities arising in the presence of external mechanical noise. Bringing together the experimental/numerical skills on rotating flows at LIMSI, and the experience of GEEPS about modelling and conception of active actuators, will address important issues about the effect of parasitic noise on closed fluid systems. The exploratory side about actuators opens wide perspectives on the application of new measurement and control techniques in a fluid set-up, in close interaction with the development of new active materials expected to contribute in the future to fluid control strategies. The study of instabilities in closed rotating flows, triggered by rotating disks, has been one of the key topics for which LIMSI is internationally recognised. Such flows have now become classical topics due to their genericity and their importance in geophysical or industrial contexts. Using an experimental device consisting of a rotating vessel partially filled with liquid and a free surface, the team at LIMSI has shown evidence for instability modes due to the free surface. The flow before the instability is axisymmetric, and this axisymmetry is broken by instability modes above a given threshold (for the angular velocity of the disk). Two cases can be identified: weak deformations of the free surface where the instability manifests itself as a array of large-scale vortices, versus strong deformations where the free surface itself has broken its axisymmetry. From an experimental point of view, measurements of the free surface height in real time demands novel techniques. Besides, the strong deformation case remains even today a true challenge for numerical simulation. However, even in the weal deformation case, threshold measurements have revealed significant departures between experimental results and numerical predictions. Sensibility methods, developed only recently in the context of open flows, appear as relevant tools to understand the effect of generic external unsteadiness (of weak amplitude and mechanical origin) on the fluid system. Moreover, adding a perfectly controlled vibration to a given flow should explain, and more importantly reduce the mismatch between observed thresholds. Devising such actuators, the associated measurement methods, and integrating them into an efficient feedback loop represent as for today important technological challenges. This project is at the junction between active control of rotating flows at LIMSI and modelling of active-material-based actuators at GEEPS. Bringing together such skills is expected to lead to both fundamental and practical progress about the sensibility of confined flows to unavoidable parasitic vibrations. The exploratory side about actuators in the large deformation regime opens new important perspectives on the development of fluid-structure simulation codes as well as on the characterisation of electro-active materials.

The present project is aimed at the implementation of a Brain-Machine-interface (BMI) by integrating memristive Spiking Neural Networks (SNN) with an intact vertebrate animal model, the zebrafish larva, by means of an optogenetic neural link. The SNN will have learning capabilities, hence the BMI may endow the larva with novel cognitive skills that are not naturally present. Conversely, the BMI may also allow to probe and search for plasticity in neural system of the animal model. The BMI will require to implement SNN able to perform the neurocomputations and implement learning with a speed that cannot be reached by software running on conventional computer hardware, such as FPGAs. We shall leverage the recent development of a novel compact spiking neuron model that is based on a new type of memristors to implement SNNs directly on hardware. The concept of memristive devices are similar to that of Mott neuristors, but the key breakthrough was to achieve the same resistive commutation properties by means of a conventional electronic device, the thyristor. This allows for simplicity in the circuit design and functional reliability. The SNNs will incorporate learning capabilities by means of electronic synaptic circuits that implement the spike-time-dependent-plasticity (STDP) rule. The project is structured along three Work Packages. The first one is to extend a mathematical theory of Rectified Linear Unit (ReLU) neuron networks, which are firing-rate coded, to SNN, which operate with explicit spikes. We shall implement sequences and other dynamical neural attractor systems. The second WP will be devoted to implement learning with STDP. We shall aim to extend the notion of associative learning to the learning of spatio-temporal sequences. The third WP is the main one, where we implement the BMI using the experimental setup of the Sumbre Lab at ENS. The BMI will allow to explore the behavior of the neural system of larva in novel ways.

Zero-emission travel, noiseless power trains and driving comfort are big advantages for electric vehicles (EV). One drawback, however, is the limited range that results from the use of smaller batteries to keep the cost down. In the day-to-day usage of such full electric vehicles (FEV) the driver has to recharge the vehicle quite. Using cables to connect vehicles in an outdoor environment is very unattractive for reasons of safety and soiling especially during winter with cold wet days. Additional drawbacks are liability issues with cables lying in the street and modification of the urban landscape. Battery recharging every day by cable could slow the growth of urban FEV fleets. The WIC2IT project offers a solution to expand FEV growth even faster by offering wireless charging. The ease-of-use of such charging systems insures that vehicles are connected to the grid more often since the driver just has to park the vehicle on the right spot and does not have to handle any bulky, heavy, dirty cables. The major challenge here is to insure that different vehicles are able to use charging spots whenever a parking space with such a spot becomes free. Successful interoperation means that even newer vehicles can be charged inductively at spots with older systems that were not specifically designed for the particular vehicle. The same is true for vehicles that might come from different manufacturers. Differences may occur since it is important to allow a free market and maximum design freedom for both vehicle manufacturers and suppliers of charging equipment. A second challenge within the scope of interoperation is in the knowledge of electromagnetic radiation. WIC2IT looks at the effect of electromagnetic radiation on living beings in order to gain valuable experience that will help determine the extent of design freedom and thus support the standardization process to make wireless charging reality in EU.

The MOCACCINO project is proposed within a social and economic context characterized by a significant increase of communication needs. In particular, we observe in particular the rapid deployment of new infrastructures, as well as the densification and ramping-up of existing ones. All these evolutions tend to increase connectivity and information circulation rate between users, thus benefiting multiple economic sectors (healthcare, mobility, industry, security etc.). This requires an optimal usage of both physical space and frequency spectrum. To that end, it is crucial to have at our disposal planar antenna systems with high efficiency, directivity and wide-band operability. These antennas ensure both low consumption communications and high data-rates. Current and future SATCOM systems constitute an illustration of these demanding requirements cohabitation. One can also cite terrestrial infrastructures for 5G+ and 6G. The Numerical developments proposed in MOCACCINO aim at supplying powerful tools for design and optimization of very compact and complex antennas, exhibiting high radio-frequency performance level and energy efficiency. This project propose to increase the maturity level of design and optimization tools initially developed in the Fast-HEM-3DSIW (ANR-16-ASTR-0001), overcoming the limitations of general-purpose commercial software. These tools will allow for the efficient and fast analysis of planar systems with very high complexity in order to meet application needs. Indeed, the high performance level relies on the fine optimization of the numerous geometrical degrees of freedom offered by multi-layer printed circuit board technology, the proper choice of materials, as well as the modeling of elements in the near-field of the antennas such as superstrates (radome, lense, frequency selective surface, metasurface). In parallel, this project propose to continue the development of multilayer corporate feed networks in printed circuit board technology, such as introduced in the initial ASTRID project in order to significantly increase gain frequency stability of slot array antennas. Finally, this numerical tool will provide better design capability for other microwave components (feed networks, filters, coupler etc.).