On cosmological expansion and local physics

We find an exact convergence in the local dynamics described by two supposedly antagonistic approaches in modern cosmology: one starting from an expanding universe perspective such as FLRW, the other based on a local model ignoring any notion of expansion, such as Schwarzschild dS. Both models are in complete agreement when the local effects of the expansion are circumscribed to the presence of the cosmological constant. We elaborate in the relevant role of static backgrounds like the Schwarzschild-dS metric in standard form as the most proper coordinatizations to describe physics at the local scale. Finally, making use of an old and too often forgotten relativistic kinematical invariant, we clarify some widespread misunderstandings on space expansion, cosmological and gravitational redshifts. As a byproduct we propose a unique and unambiguous prescription to match the local and cosmological expression of a specific observable

Forward backward asymmetries of lepton pairs in events with a large transverse momentum jet at hadron colliders

We discuss forward-backward charge asymmetries for lepton-pair production in association with a large-transverse-momentum jet at hadron colliders. The lepton charge asymmetry relative to the jet direction AjFB gives a new determination of the effective weak mixing angle sin2lept eff M2 Z with a statistical precision after cuts of 10 3 (8 10 3) at LHC (Tevatron). This is to be compared with the current uncertainty at LEP and SLD from the asymmetries alone, 2 10 4. The identification of b jets also allows for the measurement of the bottom-quark–Z asymmetry AbFB at hadron colliders, the resulting statistical precision for sin2lept eff M2 Z being 9 10 4 (2 10 2 at Tevatron), also lower than the reported precision at e+ e- colliders, 3 10 -4.Peer ReviewedPostprint (published version

Characterization of Nuclear Microsatellite Markers for Rumex bucephalophorus (Polygonaceae) Using 454 Sequencing

Premise of the study: Nuclear microsatellite markers were developed in Rumex bucephalophorus subsp. canariensis (Polygonaceae) to investigate its genetic diversity and structure. Methods and Results: Sixteen polymorphic microsatellite markers were obtained using 454 next-generation sequencing with di-, tri-, and tetranucleotide repeats. The average number of alleles was 5.688 and 3.813 for R. bucephalophorus subsp. canariensis var. canariensis and var. fruticescens, respectively. Slightly higher levels of mean genetic diversity were found in var. canariensis (expected heterozygosity = 0.600) than in var. fruticescens (expected heterozygosity = 0.514). Cross-amplifications in related taxa within R. bucephalophorus showed good amplification and polymorphic patterns. Conclusions: These 16 novel nuclear microsatellite markers are the first in the genus Rumex and may serve as valuable tools to carry out studies on genetic diversity and structure as well as progeny studies

Una especie nueva de Astragalus sect. Sesamei DC. (Leguminosae) del sureste de España: Astragalus castroviejoi

We describe a new species of Astragalus section Sesamei from the semiarid zone of SE Spain: Astragalus castroviejoi. Morphologically the new species resembles A. sesameus L. and A. stella L. and we provide a key to distinguish the three species. A. castroviejoi is a diploid species with 2n = 16, the same chromosome number as A. sesameus and A. stella. We provide an image of the karyotype, together with an illustration of the new species and a map of its distribution. Since the existing populations are restricted in area, we also provide an estimate of the conservartion status of this species according to the criteria of the IUCN.En este trabajo se describe una especie nueva de la zona semiárida del SE de España perteneciente a la sección Sesamei del género Astragalus: Astragalus castroviejoi. En lo morfológico, esta especie se parece a A. sesameus L. y A. stella L., por lo que se aporta una clave para la identificación de estas tres especies. A. castroviejoi es una especie diploide con 2n = 16, el mismo número cromosomático de A. sesameus y A. stella. Se da la descripción del cariótipo y se aporta la iconografía de la especie y un mapa de distribución. Como los núcleos poblacionales son pequeños se hace también una valoración, siguiendo los criterios de la IUCN, del estado de conservación de la especie

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

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Presentació

New design of gravitational wave detectors

We propose a novel approach to detect gravitational waves based on a semi-rigid detector. The approach relies upon the time delay that the light takes to travel from a fixed mirror at the end of a rigid bar to a nearby free mirror. We show that the dimensions of the experimental device can be shortened in comparison to the conventional ones based on two free mirrors.Peer ReviewedPostprint (published version

Hidden conformal symmetry and entropy of Schwarzschild–de Sitter spacetime

In this paper we treat two aspects of a black hole (BH) immersed in the Schwarzschild–de Sitter (SdS) spacetime. First we show that the equation of motion of a massless scalar particle near the BH horizon enjoys a hidden conformal symmetry when the two horizons satisfy a quadratic relation, not related with the Nariai limit. This hidden symmetry is S L ( 2 , R ) × S O ( 2 ) . As a second aspect of our analysis we present the leading quantum corrections, at large time, to the entropy in the semiclassical limit.Postprint (published version

Lowest resonance in QCD from low-energy data

We worked out a generalization of su(2) chiral perturbation theory, including a perturbative singlet scalar field. The approach suggests that the prediction for sensible low-energy observables converge faster towards their physical value. The physical mass and width of the scalar particle are obtained through a simultaneous analysis of the pion vector form factor and the ¿¿¿p 0 p 0 cross section. Both values are statistically consistent with the ones obtained by using Roy equations in p-p scattering. In addition we find indications that the photon-photon-singlet coupling is quite small

Insights into Q2Qbar2 states from an effective perspective

We discuss the two-photon coupling of the lightest scalar meson on the basis of an extension of χPT. Using low-energy data on the pion form factor and the γγ→π+π−(π0π0) cross sections as inputs, we find Γ(σ→γγ)≅0.126  keV. The smallness of the result and the relative weight between its components, Γγγ→S1Γγγ→ππ→S1≤1, suggests that the scalar 0++ meson is mainly a Q2Q¯2 state.Peer Reviewe