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We discuss the use of machine learning techniques in effectively nonparametric modelling of generalised parton distributions (GPDs) in view of their future extraction from experimental data. Current parameterisations of GPDs suffer from model dependency that lessens their impact on phenomenology and brings unknown systematics to the estimation of quantities like Mellin moments. The new strategy presented in this study allows to describe GPDs in a way fulfilling theory-driven constraints, keeping model dependency to a minimum. Getting a better grip on the control of systematic effects, our work will help the GPD phenomenology to achieve its maturity in the precision era commenced by the new generation of experiments.

Membrane proteins are present in both cardiac T-tubule (TTM) and outer surface membrane (OSM), although at a different density. Classical pharmacology does not allow to explore the function of a membrane protein separately in OSM vs. TTM. Here, we developed a technology based on size exclusion to explore the function of β-adrenergic receptors (β-ARs) located in the OSM. We synthetized a PEG-Iso molecule by covalent linking between isoprenaline (Iso) and a 5000 Da PolyEthylene-Glycol (PEG). Using confocal microscopy, we show that PEGylation constrains molecules outside the T-tubule network. PEG-Iso produced similar effects as Iso on I ca,L , sarcomere shortening and Ca 2+ transients. However, PEG-Iso increased [cAMP] i with a lower efficacy than Iso, produced a much lower stimulation of nuclear PKA activity than Iso but a larger stimulation of cytosolic PKA at equivalent levels of [cAMP] i . Our results show that activation of OSM β-ARs is sufficient to activate cytosolic PKA and excitation-contraction coupling, but insufficient to activate nuclear PKA or nuclear protein phosphorylation for which additional activation of TTM β-ARs is needed.

We investigate interactions between individual's position in the labor market and health status. We jointly model health, employment and working hours using a dynamic model. We estimate a dynamic multivariate model with random effects for the period going from 1991 to 2009 and using data from the British Household Panel Survey (BHPS). Instrumental variables are used. We consider interactions of the error terms of the model using a vector autoregressive process of the order 1. A shock on one component of the error term can have an impact on the distribution of the error term the next period of time. Individual effects-one for each equation-can be correlated. The model is estimated using simulated maximum likelihood estimator. We consider the initial conditions problem. We find that joint dynamics of health and employment is determined by the interactions of their past realizations as well as by the individual's socioeconomic characteristics.

In this work, a mixed domain decomposition method (LATIN) is proposed to improve the efficiency of magnetostatic simulation of rotating machines. This strategy relies on a decomposed formulation of the problem considering both primal and dual fields on the interfaces. From this formulation, the LATIN solver method gives a powerful iterative scheme to build a solution. A first implementation using the magnetic vector potential formulation in 2D is developed and is illustrated on two test cases: a ferromagnetic 2D bar and a switched reluctance motor.

International audience; Context. Near-and mid-infrared observations have revealed the presence of organic refractory materials in the solar system, in cometary nuclei and on the surface of centaurs, Kuiper-belt and trans-neptunian objects. In these astrophysical environments, organic materials can be formed because of the interaction of frozen volatile compounds with cosmic rays, stellar/solar particles, and favoured by thermal processing. The analysis of laboratory analogues of such materials gives information on their properties, complementary to observations. Aims. We present new experiments to contribute in the understanding of the chemical composition of organic refractory materials in space. Methods. We bombard frozen water, methanol and ammonia mixtures with 40 keV H + and we warm the by-products up to 300 K. The experiments allow the production of organic residues that we analyse by means of infrared spectroscopy and by Very High Resolution Mass Spectrometry to study their chemical composition and their high molecular diversity, including the presence of hexamethylenetetramine and its derivatives. Results. We find that the accumulated irradiation dose plays a role in determining the residue's composition. Conclusions. Based on the laboratory doses, we estimate the astrophysical timescales to be short enough to induce an efficient formation of organic refractory materials at the surface of icy bodies in the outer solar system.

Policymaking during a pandemic can be extremely challenging. As COVID-19 is a new disease and its global impacts are unprecedented, decisions need to be made in a highly uncertain, complex and rapidly changing environment. In such a context, in which human lives and the economy are at stake, we argue that using ideas and constructs from modern decision theory, even informally, will make policymaking more a responsible and transparent process.

Summary:The European economic union is incomplete, which makes it vulnerable to macroeconomic shocks. The opportunity to move forward in the integration process was highly debated even before the Covid-19 crisis.Yet the diverging views among countries and political groups are often considered as an obstacle on the path to required agreements for completing the Economic and Monetary Union (EMU). We present the results of a survey conducted in 2018 among members of national parliaments (MPs) in France, Germany and Italy on European integration in policy fields related to risk-sharing and budgetary institutions, asking for their opinion on proposals such as the creation of a European Unemployment Insurance (EUI), Eurobonds, or an EU tax. We find that nationality and political groups are key determinants of support for such proposals, the latter being the strongest. We describe how opinions are divided and try to identify policy proposals which could gather enough political support. The agreement reached on July 21st, 2020 at the last European summit includes financial transfers between States and the creation of Eurobonds, thus representing an important institutional move and an application of some of the reforms suggested by our survey. Yet what has been decided upon is only temporary and leaves open the question of the future of European integration.Key points: At first glance, the answers show diverging opinions on most questions between countries with Italy supporting more integration, and Germany opposing it for most proposals. France has an intermediate position, leaning towards Italy. A breakdown of the results by party affiliation shows a more nuanced picture. For cross-country comparisons, we build a party indicator using the affiliation of national parties to European political groups. National MPs associated with the group of Socialists and Democrats (S&D) at the European level show strong support for the creation of new fiscal institutions and a new EU tax, and for risk sharing institutions (European Unemployment Insurance, Eurobonds). On the contrary, MPs associated with the European People’s Party (EPP) are mildly positive or against risk-sharing and fiscal institutions. National MPs affiliated to Renew Europe hold similar views to S&D MPs, but are less supportive of risk-sharing mechanisms. There is a substantial diversity of positions between the German AfD, the Italian Lega and the 5-star movement: the three parties have diverging views on the future of integration. Our econometric analysis shows that party affiliations have more explanatory power than nationality for all questions. This clearly shows that outcomes of national parliamentary elections could change the overall support for any issue.; Summary:The European economic union is incomplete, which makes it vulnerable to macroeconomic shocks. The opportunity to move forward in the integration process was highly debated even before the Covid-19 crisis.Yet the diverging views among countries and political groups are often considered as an obstacle on the path to required agreements for completing the Economic and Monetary Union (EMU). We present the results of a survey conducted in 2018 among members of national parliaments (MPs) in France, Germany and Italy on European integration in policy fields related to risk-sharing and budgetary institutions, asking for their opinion on proposals such as the creation of a European Unemployment Insurance (EUI), Eurobonds, or an EU tax. We find that nationality and political groups are key determinants of support for such proposals, the latter being the strongest. We describe how opinions are divided and try to identify policy proposals which could gather enough political support. The agreement reached on July 21st, 2020 at the last European summit includes financial transfers between States and the creation of Eurobonds, thus representing an important institutional move and an application of some of the reforms suggested by our survey. Yet what has been decided upon is only temporary and leaves open the question of the future of European integration.Key points: At first glance, the answers show diverging opinions on most questions between countries with Italy supporting more integration, and Germany opposing it for most proposals. France has an intermediate position, leaning towards Italy. A breakdown of the results by party affiliation shows a more nuanced picture. For cross-country comparisons, we build a party indicator using the affiliation of national parties to European political groups. National MPs associated with the group of Socialists and Democrats (S&D) at the European level show strong support for the creation of new fiscal institutions and a new EU tax, and for risk sharing institutions (European Unemployment Insurance, Eurobonds). On the contrary, MPs associated with the European People’s Party (EPP) are mildly positive or against risk-sharing and fiscal institutions. National MPs affiliated to Renew Europe hold similar views to S&D MPs, but are less supportive of risk-sharing mechanisms. There is a substantial diversity of positions between the German AfD, the Italian Lega and the 5-star movement: the three parties have diverging views on the future of integration. Our econometric analysis shows that party affiliations have more explanatory power than nationality for all questions. This clearly shows that outcomes of national parliamentary elections could change the overall support for any issue.

International audience; The first observation of coherent elastic neutrino-nucleus scattering (CE ν NS), reported by the COHERENT Collaboration in 2017, paved the way for a new generation of experiments using reactor ν̄e and aiming at precisely measuring this process. In this context, the BASKET (Bolometers At Sub-KeV Energy Thresholds) R&D; project investigates the use of cryogenic detectors for a reactor CE ν NS experiment. This article reports on the first test of a Mo-doped lithium tungstate scintillating bolometer ( ⊘ 18 × 7 mm, 8 g), performed in an aboveground laboratory at CSNSM, Orsay (France). The detector bolometric performance (energy and time response, particle identification capabilities) and radiopurity have been studied and confirm the promising potential of lithium tungstate-based bolometric detectors for the measurement of CE ν NS at reactors.

Cette thèse se compose de trois articles. Les deux premiers articles étudient les flux d'informations sur les marchés financiers, et le troisième étudie comment les familles de fonds communs de placement peuvent utiliser des sources de revenus relativement discrétionnaires pour canaliser des bénéfices vers des fonds spécifiques au sein de la famille. Le premier article, rédigé en collaboration avec Daniel Schmidt, étudie les retombées de prix et de liquidité sur les marchés financiers. En utilisant une expérience quasi-naturelle, nous montrons que les investisseurs observent les prix des actions pour en extraire des signaux, et les utilisent pour effectuer des transactions. Dans le deuxième article, je montre que les fonds d'investissement acquièrent des informations par le marché des prêts de titres. Je montre que les fonds communs de placement actifs vendent les actions qui leur sont empruntées par des vendeurs à découvert, alors que les fonds indiciels - qui sont interdits de négociation - ne le font pas. D'un autre côté, les fonds indiciels sont en mesure de facturer des frais de prêt de titres plus élevés aux emprunteurs. Je leur attribue le fait qu'ils sont de meilleurs prêteurs dans le sens où ils ne peuvent pas utiliser les informations qu'ils obtiennent pour négocier, et donc tirer des bénéfices des informations des vendeurs à découvert. Le troisième article, également avec Daniel Schmidt, étudie les politiques des familles de fonds en matière de répartition des prêts de titres et des revenus de prêts entre les fonds membres. Nous montrons que les familles de fonds s'écartent de l'allocation équitable revendiquée, en dirigeant davantage de prêts de titres et de bénéfices de prêts vers les fonds indiciels. Cette conclusion est conforme à la substitution par les fonds des frais de gestion plus faibles par des revenus de prêts de titres plus élevés. This thesis consists of three articles. The two first articles study information flows in the financial markets, and the third one studies how mutual fund families may use relatively discretionary income sources to channel profits to specific funds within the family. The first article, joint with Daniel Schmidt, studies price and liquidity spillovers in financial markets. Using a quasi-natural experiment, we show that investors look at stock prices to extract signals, and use these to trade. In the second article, I show that mutual fund acquire information through the securities lending market. I show that active mutual funds start selling the stocks that are borrowed from them by short sellers, whereas index funds — that are prohibited from trading — do not. One the other hand, index funds are able to charge higher stock lending fees from the borrowers. I attribute this to them being better lenders in the sense that they can not use the information they gain to trade, and thereby extract profits from the short sellers’ information. The third article, also with Daniel Schmidt, studies fund family level policies in allocating securities loans and lending revenues between member funds. We show that fund families deviate from the claimed fair allocation, directing more securities loans and lending profits to index funds. The finding is in line with with funds substituting a lower expense ratio with higher securities lending income.

subm. to Phys. Rev. Fluids; International audience; We investigate numerically the influence of currents on wind-generated surface deformations for wind velocity below the onset of regular waves. In that regime, the liquid surface is populated by small disorganised deformations elongated in the streamwise direction, referred to as wrinkles. These wrinkles are the superposition of incoherent wakes generated by the pressure fluctuations traveling in the turbulent boundary layer. In this work, we account for the effect of a current in the liquid, either longitudinal or transverse, by including a modified Doppler-shifted dispersion relation in the spectral theory previously derived by Perrard et al. [J. Fluid Mech. 873, 1020-1054 (2019)]. We use the pressure data from direct numerical simulation of the turbulent air flow to compute the surface deformation, and determine the wrinkle properties (size and amplitude) as a function of the liquid viscosity and current properties (surface velocity, thickness and orientation). We find significant modifications of the wrinkle geometry by the currents: the wrinkles are tilted for a transverse current, and show finer scales for a longitudinal current. However, their characteristic size is weakly affected, and their amplitude remains independent of the current. We discuss the implications of these results regarding the onset of regular waves at larger wind velocity. In this work, we introduce a new spectral interpolation method to evaluate the surface deformation fields, based on a refined meshing close to the resonance. This method, which can be extended to any dispersive system excited by a random forcing, strongly reduces the discretization effects at a low computational cost.