Euclid preparation: Determining the weak lensing mass accuracy and precision for galaxy clusters

International audienceWe investigate the level of accuracy and precision of cluster weak-lensing (WL) masses measured with the \Euclid data processing pipeline. We use the DEMNUni-Cov $N$-body simulations to assess how well the WL mass probes the true halo mass, and, then, how well WL masses can be recovered in the presence of measurement uncertainties. We consider different halo mass density models, priors, and mass point estimates. WL mass differs from true mass due to, e.g., the intrinsic ellipticity of sources, correlated or uncorrelated matter and large-scale structure, halo triaxiality and orientation, and merging or irregular morphology. In an ideal scenario without observational or measurement errors, the maximum likelihood estimator is the most accurate, with WL masses biased low by $\langle b_M \rangle = -14.6 \pm 1.7 \, \%$ on average over the full range $M_\text{200c} > 5 \times 10^{13} \, M_\odot$ and $z < 1$. Due to the stabilising effect of the prior, the biweight, mean, and median estimates are more precise. The scatter decreases with increasing mass and informative priors significantly reduce the scatter. Halo mass density profiles with a truncation provide better fits to the lensing signal, while the accuracy and precision are not significantly affected. We further investigate the impact of additional sources of systematic uncertainty on the WL mass, namely the impact of photometric redshift uncertainties and source selection, the expected performance of \Euclid cluster detection algorithms, and the presence of masks. Taken in isolation, we find that the largest effect is induced by non-conservative source selection. This effect can be mostly removed with a robust selection. As a final \Euclid-like test, we combine systematic effects in a realistic observational setting and find results similar to the ideal case, $\langle b_M \rangle = - 15.5 \pm 2.4 \, \%$, under a robust selection

Predicting coarse-grained representations of biogeochemical cycles from metabarcoding data

Taxonomic analysis of environmental microbial communities is now routinely performed thanks to advances in DNA sequencing. Determining the role of these communities in global biogeochemical cycles requires the identification of their metabolic functions, such as hydrogen oxidation, sulfur reduction, and carbon fixation. These functions can be directly inferred from metagenomics data, but in many environmental applications metabarcoding is still the method of choice. The reconstruction of metabolic functions from metabarcoding data and their integration into coarse-grained representations of geobiochemical cycles remains a difficult bioinformatics problem today. Results We developed a pipeline, called Tabigecy, which exploits taxonomic affiliations to predict metabolic functions constituting biogeochemical cycles. In a first step, Tabigecy uses the tool EsMeCaTa to predict consensus proteomes from input affiliations. To optimise this process, we generated a precomputed database containing information about 2,404 taxa from UniProt. The consensus proteomes are searched using bigecyhmm, a newly developed Python package relying on Hidden Markov Models to identify key enzymes involved in metabolic function of biogeochemical cycles. The metabolic functions are then projected on coarse-grained representation of the cycles. We applied Tabigecy to two salt cavern datasets and validated its predictions with microbial activity and hydrochemistry measurements performed on the samples. The results highlight the utility of the approach to investigate the impact of microbial communities on geobiochemical processes

Turkey’s Walled Borders: A Multiscalar Approach

International audienceIn addition to the walls built by Bulgaria on the Turkish-Bulgarian border and by Greece on the Greek-Turkish one, Turkey itself launched the construction of a concrete wall on its border with Syria in 2015. Two years later, it continued this policy of enclosure with the construction of a wall on its border with Iran. While the fortification of borders is not a dynamic peculiar to Turkey, a multiscalar approach enables us to situate this fortification policy within Turkey's own regional space. Observing these two walls on different geographical scales allows us to understand the converging interests of the various players involved in this strategy of fortification. This also makes it possible to draw out discourses that are probably less visible, such as the European Union's support for the creation of these walls

Space-time first-order correlations of an open Bose-Hubbard model with incoherent pump and loss

30 pages, 15 figuresInternational audienceWe investigate the correlation properties in the steady state of driven-dissipative interacting bosonic systems in the quantum regime, as for example non-linear photonic cavities. Specifically, we consider the Bose-Hubbard model on a periodic chain and with spatially homogeneous one-body loss and pump within the Markovian approximation. The steady state corresponds to an infinite temperature state at finite chemical potential with diagonal spatial correlations. Nonetheless, we observe a nontrivial behaviour of the space-time two-point correlation function in the steady state, obtained by exact diagonalisation. In particular, we find that the decay width of the propagator is not only renormalised at increasing interactions, as it is the case of a single non-linear resonator, but also at increasing hopping strength. We then compute the full spectral function, finding that it contains both a dispersive free-particle like dispersion at low energy and a doublon branch at energy corresponding to the on-site interactions. We compare with the corresponding calculation for the ground state of a closed quantum system and show that the driven-dissipative nature - determining both the steady state and the dynamical evolution - changes the low-lying part of the spectrum, where noticeably, the dispersion is quadratic instead of linear at small wavevectors

Negated actions are simulated within the primary motor cortex

International audienceControversy persists regarding the representation of linguistically negated actions, specifically concerning activation and inhibitory mechanisms in the motor system, and whether negated action sentences evoke an initial motor simulation of the action to be negated. We conducted two experiments probing corticospinal excitability (CSE) and short-interval intracortical inhibition (SICI) in the primary motor cortex at different latencies while reading affirmative and negative action sentences. In experiment one, twenty-six participants read action and non-action sentences in affirmative or negative forms. Using transcranial magnetic stimulation, we probed CSE in hand muscles at rest and at several latencies after verb presentation. We observed a greater CSE for action sentences compared to non-action sentences, regardless of verb form. In experiment two, nineteen participants read affirmative and negative action sentences. We measured CSE and SICI at short and long latencies after verb presentation. CSE was greater for affirmative and negative action sentences at both latencies compared to rest. SICI did not change at the short latency but increased at longer latencies, regardless of verb form. Negated action sentences showed the same motor excitability as affirmed action sentences with no additional inhibition at early latencies. These results lend support for the idea that actions to be negated are initially simulated within the motor system. Neural differences between affirmative and negative action sentences may occur outside the primary motor cortex

Choix, Présentation et annotation de textes de consolation du premier XVIIe siècle ( Théophile de Viau, Tristan L'Hermite, Malherbe)

International audienceThe volume édits a collection of texts on consolation, classified by topic, period, or practices. My work involved selecting, editing, and presenting the practice of consolation for four lyric texts: Théophile de Viau, "Consolation à M. de L.," 1621; Tristan, "Consolation à Monsieur de Gournay sur la perte de deux de ses enfants," Epitaph-Tombeau 10, La Lyre, 1643; Malherbe, "Vers de Malherbe à madame la comtesse sur la mort de sa fille," [1599]Le volume propose d'éditer un ensemble de textes sur la consolation, classées par topique, période ou pratiques. Mon travail a consisté à choisir, éditer et présenter la pratique de la consolation pour 4 textes lyriques: Théophile de Viau, « Consolation à M. de L. », 1621, Tristan, « Consolation à Monsieur de Gournay sur la perte de deux de ses enfans », épitaphe-tombeau 10., La Lyre, 1643; Malherbe, "Vers de Malherbe à madame la comtesse sur la mort de sa fille", [1599] 

Une goutte de sang

Alm@e Linguae n°2 Un@ Editions / PUPPATraduction inédite du récit La gota de sangre (1911) de Emilia Pardo Bazán, premier récit policier long de l'histoire du genre en Espagn

Multifunctional Expectile Regression Estimation in Volterra Time Series: Application to Financial Risk Management

International audienceWe aim to analyze the dynamics of multiple financial assets with variable volatility. Instead of a standard analysis based on the Black–Scholes model, we proceed with the multidimensional Volterra model, which allows us to treat volatility as a stochastic process. Taking advantage of the long memory function of this type of model, we analyze the reproduced movements using recent algorithms in the field of functional data analysis (FDA). In fact, we develop, in particular, new risk tools based on the asymmetric least squares loss function. We build an estimator using the multifunctional kernel (MK) method and then establish its asymptotic properties. The multidimensionality of the Volterra process is explored through the dispersion component of the convergence rate, while the nonparametric path of the risk tool affects the bias component. An empirical analysis is conducted to demonstrate the ease of implementation of our proposed approach. Additionally, an application on real data is presented to compare the effectiveness of expectile-based measures with Value at Risk (VaR) in financial risk management for multiple assets

Comment les personnes bien-voyantes expérimentent-elle le sens des masses ?

Fabrique du sensible & mutations des espaces habitésSi le sens des masses est utilisé quotidiennement par les personnes non-voyantes, nous ne savons pas si les personnes bien-voyantes peuvent en faire l’expérience, ni si cette expérience s’apparente à celle expérimentée par les personnes non-voyantes. Un parcours, préalablement déterminé dans le centre-ville de Nantes, a été réalisé par 19 participants bien-voyants et bien-entendants. Les résultats montrent, d’une part, que les participants bien-voyants sont capable d’expérimenter le sens des masses rapidement et sans entrainement et, d’autre part, qu’ils font l’expérience de sa phénoménologie complexe, synesthésique et multimodale. Ces conclusions amènent à penser que le sens des masses existe de façon préréflexive et automatisée chez toutes personnes bien-entendante et sous-tendent une implication dans l’expérience sensible et affective des espaces urbains

The golden triangle of place reputation for metropolitaninternational cities: the cases of London and Paris

International audienceThis prescient book explores the relationship between city branding, reputation management and tourism development through a comprehensive collection of propositions to re-examine and refine city branding tools and ideas.Enhancing the existing literature and with contributions from cities across four continents, chapters set out how city branding relates to urban identity and image, city reputation and sustainable tourism development. Illustrating how city branding can contribute towards a more sustainable future for cities, the book transcends disciplinary boundaries and uses methodological propositions to provide an innovative assessment of the current status of reputation management and tourism development. Showcasing new understandings of tools and conceptualizations, this forward-thinking book develops this field of study in both theory and practice.City Branding is an excellent resource not only for scholars of urban studies and tourism management but also for those studying local development, planning, urban governance, placemaking and place management