RED: Deep Recurrent Neural Networks for Sleep EEG Event Detection

The brain electrical activity presents several short events during sleep that can be observed as distinctive micro-structures in the electroencephalogram (EEG), such as sleep spindles and K-complexes. These events have been associated with biological processes and neurological disorders, making them a research topic in sleep medicine. However, manual detection limits their study because it is time-consuming and affected by significant inter-expert variability, motivating automatic approaches. We propose a deep learning approach based on convolutional and recurrent neural networks for sleep EEG event detection called Recurrent Event Detector (RED). RED uses one of two input representations: a) the time-domain EEG signal, or b) a complex spectrogram of the signal obtained with the Continuous Wavelet Transform (CWT). Unlike previous approaches, a fixed time window is avoided and temporal context is integrated to better emulate the visual criteria of experts. When evaluated on the MASS dataset, our detectors outperform the state of the art in both sleep spindle and K-complex detection with a mean F1-score of at least 80.9% and 82.6%, respectively. Although the CWT-domain model obtained a similar performance than its time-domain counterpart, the former allows in principle a more interpretable input representation due to the use of a spectrogram. The proposed approach is event-agnostic and can be used directly to detect other types of sleep events.Comment: 8 pages, 5 figures. In proceedings of the 2020 International Joint Conference on Neural Networks (IJCNN 2020

Infrared propagators of Yang-Mills theory from perturbation theory

We show that the correlation functions of ghosts and gluons for the pure Yang-Mills theory in Landau gauge can be accurately reproduced for all momenta by a one-loop calculation. The key point is to use a massive extension of the Faddeev-Popov action. The agreement with lattice simulation is excellent in d=4. The one-loop calculation also reproduces all the characteristic features of the lattice simulations in d=3 and naturally explains the pecularities of the propagators in d=2.Comment: 4 pages, 4 figures

Hi ha una història social de la llengua catalana?

La lingüística històrica ha produït al llarg de l'últimsegle estudis notables sobre l'evolució formal de la llengua catalana. A més, en les últimes dècades s'ha desenvolupat una sociolingüística catalana que connecta la teoria i la descripció empírica amb la política lingüística. No obstant això, no s'ha gestat una història social de la llengua, o una sociolingüística històrica en sentit estricte, més enllà d'alguns esforços individuals. Les raons d'aquest dèficit són internes (les limitacions de l'objecte d'estudi, la inèrcia i l'estancament dels estudis filològics...) i externes (els condicionants sociopolítics i de mercat que pesen sobre el català). Per això es proposa avançar cap a un nou paradigma en què la diacronia lingüística s'integri dins de les ciències socials, obertes a l'autocrítica i la superació de l'apriorisme ideològic.Does the Catalan language have a social history?. Over the last century, historical linguistics has produced notable studies on the formal evolution of the Catalan language.Moreover, in recent decades Catalan sociolinguistics has been developed, connecting theory and empirical description to language policy. However, a social history of the Catalan language has not been developed nor historical sociolinguistics, strictly speaking, bar a few random examples. The reasons for this deficit are both internal (the limitations of the subject matter, the inertia and the stagnation of philological studies…) and external (the socio-political andmarket constraints imposed on the Catalan language). We therefore propose to move towards a new paradigm in which the linguistic diachrony is integrated within social sciences, open to self-criticism and to overcoming ideological apriorism

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Background and aims: Juncus is the largest and most diverse genus of Juncaceae, distributed mainly in the temperate zones of both hemispheres. The Southern Cone flora contains ca. 38 Juncus species (44 taxa including 12 infraspecific categories). Sixteen of those species belong to the section Ozophyllum. As a part of our ecologic studies in wetlands of Patagonia (Argentina) we collected specimens of Juncus that did not match any of the species currently known to the Southern Cone. The aim of this contribution is to report for the first time the presence of Juncus articulatus subsp. articulatus for the Southern Cone flora.  M&M: Classical methods in taxonomy were employed. Living and herbarium material, original descriptions, and type material of Juncus articulatus subsp. articulatus were studied. Collected materials were deposited in the herbarium ARC of the Universidad Nacional del Comahue. Results: Juncus articulatus subsp. articulatus is here described. A distribution map, photos, and a key to the Southern Cone species of Juncus belonging to the section Ozophyllum are provided. Also, some ecological and distributional features are discussed.  Conclusions: The naturalization of Juncus articulatus subsp. articulatus is reported here for the first time in the Southern Cone. From now on, Juncus contributes 39 species to the Southern Cone flora, and 17 to Juncus section Ozophyllum.Introducción y objetivos: Juncus es el género más grande y diverso de Juncaceae, distribuido en zonas templadas de ambos hemisferios. La flora del Cono Sur contiene ca. 38 especies de Juncus (44 taxones que incluyen 12 categorías infraespecíficas). Dieciséis de esas especies pertenecen a la sección Ozophyllum. Como parte de nuestros estudios ecológicos en humedales de la Patagonia (Argentina), hemos coleccionado especímenes de Juncus que no coincidían con ninguna de las especies actualmente conocidas en el Cono Sur. El objetivo de esta contribución es reportar por primera vez la presencia de Juncus articulatus subsp. articulatus para la flora del Cono Sur. M&M: Se emplearon los métodos clásicos de taxonomía. Se estudió material vivo y de herbario, descripciones originales y material tipo de Juncus articulatus subsp. articulatus. El material coleccionado fue depositado en el herbario ARC de la Universidad Nacional del Comahue. Resultados: Se describe a Juncus articulatus subsp. articulatus. Se proporciona un mapa de distribución, fotografías y una clave de las especies de Juncus pertenecientes a la sección Ozophyllum presentes en el Cono Sur. Se discuten algunas características ecológicas y de distribución de la especie. Conclusiones: Se reporta por primera vez la naturalización de Juncus articulatus subsp. articulatus en el Cono Sur. Desde ahora, Juncus aporta 39 especies a la flora del Cono Sur, y 17 a la sección Ozophyllum.- &nbsp

LHC sensitivity to singly-charged scalars decaying into electrons and muons

Current LHC searches for non-supersymmetric singly-charged scalars, based on Two-Higgs-Doublet models, in general focus the analysis on third-generation fermions in the final state. However, singly-charged scalars in alternative extensions of the scalar sector involve Yukawa couplings not proportional to the mass of the fermions. Assuming the scalar decays into electrons and muons, it can manifest cleaner experimental signatures. In this paper we suggest that a singly-charged scalar singlet, with electroweak production, can start to be probed in the near future with dedicated search strategies. Depending on the strength of the Yukawa couplings, two independent scenarios are considered: direct pair-production (small couplings) and single-production via virtual neutrino exchange (large couplings). We show that, up to a mass as large as 500 GeV, most of the parameter space could be excluded at the 95% C.L. in a high-luminosity phase of the LHC. Our results also apply to other frameworks, provided the singly-charged scalar exhibits similar production patterns and dominant decay modes.Comment: 15 pages, 8 figure

Transport and invariant manifolds near L3 in the Earth-Moon Bicircular model

This paper focuses on the role of $\mathrm{L}_3$ to organise trajectories for a particle going from Earth to Moon and viceversa, and entering or leaving the Earth-Moon system. As a first model, we have considered the planar Bicircular problem to account for the gravitational effect of the Sun on the particle. The first step has been to compute a family of hyperbolic quasi-periodic orbits near $\mathrm{L}_3$. Then, the computation of their stable and unstable manifolds provides connections between Earth and Moon, and also generates trajectories that enter and leave the Earth-Moon system. Finally, by means of numerical simulations based on the JPL ephemeris we show that these connections can guide the journey of lunar ejecta towards the Earth