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The beta decay of the free neutron provides several probes to test the Standard Model of particle physics as well as to search for extensions thereof. Hence, multiple experiments investigating the decay have already been performed, are under way or are being prepared. These measure the mean lifetime, angular correlation coefficients or various spectra of the charged decay products (proton and electron). NoMoS, the Neutron decay prOducts MOmentum Spectrometer, presents a novel method of momentum spectroscopy: it utilizes the $R \times B$ drift effect to disperse charged particles dependent on their momentum in an uniformly curved magnetic field. This spectrometer is designed to precisely measure momentum spectra and angular correlation coefficients in free neutron beta decay to test the Standard Model and to search for new physics beyond. With NoMoS, we aim to measure inter alia the electron-antineutrino correlation coefficient $a$ and the Fierz interference term $b$ with an ultimate precision of $\Delta a/a < 0.3\%$ and $\Delta b < 10^{-3}$ respectively. In this paper, we present the measurement principles, discuss measurement uncertainties and systematics, and give a status update. Comment: 7 pages, 4 figures, accepted to the Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 2018

Abstract We resolve the long-standing mysterious discrepancy between the experimental magic angle in EELS— ∼ 2 ϑ E —and the quantum mechanical prediction of ∼ 4 ϑ E . A relativistic approach surpassing the usually applied kinematic correction yields a magic angle close to the experimental value. The reason is that the relativistic correction of the inelastic scattering cross section in anisotropic systems is significantly higher than in isotropic ones.

International audience; Sliced Inverse Regression (SIR) has been extensively used to reduce the dimension of the predictor space before performing regression. SIR is originally a model free method but it has been shown to actually correspond to the maximum likelihood of an inverse regression model with Gaussian errors. This intrinsic Gaussianity of standard SIR may explain its high sensitivity to outliers as observed in a number of studies. To improve robustness, the inverse regression formulation of SIR is therefore extended to non-Gaussian errors with heavy-tailed distributions. Considering Student distributed errors it is shown that the inverse regression remains tractable via an Expectation- Maximization (EM) algorithm. The algorithm is outlined and tested in the presence of outliers, both in simulated and real data, showing improved results in comparison to a number of other existing approaches.

The martensitic hcp→dhcp transformation was studied in single crystals of Co-0.85 at.%Fe by transmission electron microscopy (TEM) methods. During in-situ heating dhcp lamellae emerge into the hcp areas of the TEM specimens. The minimum thickness of the lamellae is about 15 close packed planes. Frequently lamellae are observed that grow in thickness by the movement of superledges that are up to about 100 close packed planes in height. The partials at the fronts of the transformation were analysed on an atomic level in TEM images with atomic resolution. The analysis shows that the transformation fronts consists of a sequence of very narrow dipoles compensating their long range strain fields. Since dipoles of a common Burgers vector are observed it is proposed that their short range interactions might promote their correlated nucleation.

Let $\mathbf{k}$ be an arbitrary field. For any fixed badly approximable power series $\Theta$ in $\mathbf{k}((X^{-1}))$, we give an explicit construction of continuum many badly approximable power series $\Phi$ for which the pair $(\Theta, \Phi)$ satisfies the Littlewood conjecture. We further discuss the Littlewood conjecture for pairs of algebraic power series.

International audience; Electric or hybrid vehicles are very silent, which represents a major advantage for the reduction of noise annoyance in urban areas. But this makes them dangerous for pedestrians, especially vulnerable ones as visually-impaired people. Current solutions consist in using warning sound so that the exterior noise of an electric vehicle is as high as for a conventional one. This may cancel the benefit of electric vehicles for the reduction of sound annoyance. The eVADER project (funded by the European Commission) aims at proposing a prototype car which combines a high safety and a low noise level. A part of the the work program consisted in perceptual studies. The goal of these studies was to evaluate the influence of various timbre parameters on the detectability and the unpleasantness of a warning sound. Results show that it is possible to make an electric vehicle easily detected while keeping its sound level much lower than the one of a conventional car.

International audience; The evaluation of vaccine strategies in animal models is essential for the development of a vaccine against HIV. In efficacy trials conducted in non-human primate models of AIDS, vaccines based on adenoviruses compared favourably with other vaccine vectors. To determine whether this strategy could be transposed to another animal model, and by extension, to humans, we have evaluated the efficacy of adenoviral vectors in a natural model of AIDS, infection of the cat by the feline immunodeficiency virus (FIV). Recombinant canine adenoviruses expressing the envelope glycoproteins or the Gag protein of a primary strain of FIV were constructed. Three groups of six cats were immunised twice with vectors expressing FIV antigens or with a vector expressing an irrelevant antigen, green fluorescent protein, by intramuscular and subcutaneous routes. Humoral responses were elicited against the transgene product in 6/6, 3/6 and 0/6 cats after immunisation against green fluorescent protein, Gag or the envelope glycoproteins, respectively. Six weeks after the second administration, cats were challenged by the intraperitoneal route with the homologous strain, and viral burden in plasma was followed by quantitative RT-PCR. Immunisation with FIV antigens did not afford protection. Rather, viral RNA was detected at earlier time points in cats immunised against Gag than in cats immunised with a vector expressing an irrelevant antigen. Such immune-mediated enhancement did not appear to have a long-range impact on viral set point or inversion of the CD4(+)/CD8(+) ratio. Thus, in the feline AIDS model pre-existing immunity against a viral antigen exacerbated acute phase infection.

International audience; We consider a prototypical nonlinear reaction-diffusion system arising in reversible chemistry. Based on recent existence results of global weak and classical solutions derived from entropy-decay related a-priori estimates and duality methods, we prove exponential convergence of these solutions towards equilibrium with explicit rates in all space dimensions.The key step of the proof establishes an entropy entropy-dissipation estimate, which relies only on natural a-priori estimates provided by mass-conservation laws and the decay of an entropy functional.

The emergence of electronic health records has highlighted the need for semantic standards for representation of observations in laboratory medicine. Two such standards are LOINC, with a focus on detailed encoding of lab tests, and SNOMED CT, which is more general, including the representation of qualitative and ordinal test results. In this paper we will discuss how lab observation entries can be represented using SNOMED CT. We use resources provided by the Regenstrief Institute and SNOMED International collaboration, which formalize LOINC terms as SNOMED CT post-coordinated expressions. We demonstrate the benefits brought by SNOMED CT to classify lab tests. We then propose a SNOMED CT based model for lab observation entries aligned with the BioTopLite2 (BTL2) upper level ontology. We provide examples showing how a model designed with no ontological foundation can produce misleading interpretations of inferred observation results. Our solution based on a BTL2 conformant formal interpretation of SNOMED CT concepts allows representing lab test without creating unintended models. We argue in favour of an ontologically explicit bridge between compositional clinical terminologies, in order to safely use their formal representations in intelligent systems.

We present CIGALE (Burgarella et al. 2005; Noll et al. 2009), a software developed at the Laboratoire d'Astrophysique de Marseille to fit galaxy spectral energy distributions from the rest-frame far-UV to far-IR wavelength range, and to derive some of their physical parameters. We also give some examples of scientific results obtained with CIGALE. 4 pages, 2 figures, proceeding of a poster to be presented at ADASS XXI in Paris