Thermodynamical properties of the ICM from hydrodynamical simulations

Modern hydrodynamical simulations offer nowadays a powerful means to trace the evolution of the X-ray properties of the intra-cluster medium (ICM) during the cosmological history of the hierarchical build up of galaxy clusters. In this paper we review the current status of these simulations and how their predictions fare in reproducing the most recent X-ray observations of clusters. After briefly discussing the shortcomings of the self-similar model, based on assuming that gravity only drives the evolution of the ICM, we discuss how the processes of gas cooling and non-gravitational heating are expected to bring model predictions into better agreement with observational data. We then present results from the hydrodynamical simulations, performed by different groups, and how they compare with observational data. As terms of comparison, we use X-ray scaling relations between mass, luminosity, temperature and pressure, as well as the profiles of temperature and entropy. The results of this comparison can be summarised as follows: (a) simulations, which include gas cooling, star formation and supernova feedback, are generally successful in reproducing the X-ray properties of the ICM outside the core regions; (b) simulations generally fail in reproducing the observed ``cool core'' structure, in that they have serious difficulties in regulating overcooling, thereby producing steep negative central temperature profiles. This discrepancy calls for the need of introducing other physical processes, such as energy feedback from active galactic nuclei, which should compensate the radiative losses of the gas with high density, low entropy and short cooling time, which is observed to reside in the innermost regions of galaxy clusters.Comment: 26 pages, 12 figures, accepted for publication in Space Science Reviews, special issue "Clusters of galaxies: beyond the thermal view", Editor J.S. Kaastra, Chapter 13; work done by an international team at the International Space Science Institute (ISSI), Bern, organised by J.S. Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke

Restriction of Odd Degree Characters of Sn\mathfrak{S}_n

Let $n$ and $k$ be natural numbers such that $2^k < n$. We study the restriction to $\mathfrak{S}_{n-2^k}$ of odd-degree irreducible characters of the symmetric group $\mathfrak{S}_n$. This analysis completes the study begun in [Ayyer A., Prasad A., Spallone S., Sem. Lothar. Combin. 75 (2015), Art. B75g, 13 pages] and recently developed in [Isaacs I.M., Navarro G., Olsson J.B., Tiep P.H., J. Algebra 478 (2017), 271-282]

Arcadi Navarro

La natura &eacute;s absolutament conflictiv

Synopsis of the genus "Teucrium" L. (Lamiaceae) in Morocco

Sinopsis del género Teucrium (Lamiaceae) en Marruecos. Para el género Teucrium en Marruecos, se reconocen 60 taxa distribuidos en 52 especies ordenadas en 8 secciones. La nomenclatura correcta ha sido establecida en base a las sinonimias principales y designación de tipos en la mayoría de los casos. Se proponen tres nuevas combinaciones para el género Teucrium en Marruecos: T. rifanum (Maire & Sennen) T. Navarro & El Oualidi, T. joannis (Sauvage & Vindt) El Oualidi, T. Navarro & A. Martin y T. embergeri (Sauvage & Vindt) El Oualidi, T. Navarro & A. Martin

Dissecting the multifunctional role of the N-terminal disordered domain of a plant virus coat protein in RNA packaging, viral movement and interference with antiviral plant defense

[EN] The coat protein (CP) of Melon necrotic spot virus (MNSV) is structurally composed of three major domains. The middle S-domain builds a robust protein shell around the viral genome, whereas the C-terminal protruding domain, or P-domain, is involved in the attachment of virions to the transmission vector. Here, we have shown that the N-terminal domain, or R-domain, and the arm region, which connects the R-domain and S-domain, are involved in different key steps of the viral cycle, such as cell-to-cell movement and the suppression of RNA silencing and pathogenesis through their RNA-binding capabilities. Deletion mutants revealed that the CP RNA-binding ability was abolished only after complete, but not partial, deletion of the R-domain and the arm region. However, a comparison of the apparent dissociation constants for the CP RNA-binding reaction of several partial deletion mutants showed that the arm region played a more relevant role than the R-domain in in vitro RNA binding. Similar results were obtained in in vivo assays, although, in this case, full-length CPs were required to encapsidate full-length genomes. We also found that the R-domain carboxyl portion and the arm region were essential for efficient cell-to-cell movement, for enhancement of Potato virus X pathogenicity, for suppression of systemic RNA silencing and for binding of small RNAs. Therefore, unlike other carmovirus CPs, the R-domain and the arm region of MNSV CP have acquired, in addition to other essential functions such as genome binding and encapsidation functions, the ability to suppress RNA silencing by preventing systemic small RNA transport.This work was funded by grant BIO2014-54862-R from the Spanish Ministry of Science and Innovation and the Prometeo Program GV2014/010 from the Generalitat Valenciana. J.A.N. and M.S.-S. are the recipients of a postdoctoral contract and a PhD fellowship, respectively, from the Ministerio de Educacion y Ciencia of Spain. We thank L. Corachan for technical assistance. The authors have no conflicts of interest to declare.Serra Soriano, M.; Navarro Bohigues, JA.; Pallás Benet, V. (2017). Dissecting the multifunctional role of the N-terminal disordered domain of a plant virus coat protein in RNA packaging, viral movement and interference with antiviral plant defense. Molecular Plant Pathology. 18(6):837-849. https://doi.org/10.1111/mpp.12448S83784918

First Results from the rapid-response spectrophotometric characterization of Near-Earth Objects

As part of our multi-observatory, multi-filter campaign, we present \rmi color observations of 82 Near-Earth Objects (NEOs) obtained with the RATIR instrument on the 1.5m robotic telescope at the San Pedro Martir's National Observatory in Mexico. Our project is particularly focused on rapid response observations of small ($\lesssim 850$ m) NEOs. The rapid response and the use of spectrophotometry allows us to constrain the taxonomic classification of NEOs with high efficiency. Here we present the methodology of our observations and our result, suggesting that the ratio of C-type to S-type asteroids in a size range of $\sim$30-850m is 1.1, which is in accordance with our previous results. We also find that 10$\%$ of all NEOs in our sample are neither C- nor S-type asteroidsComment: 31 pages, 4 tables, 10 figure