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Context. Biases in mass measurements of galaxy clusters are one of the major limiting systematics in constraining cosmology with clusters. Aims. We aim to demonstrate that the systematics associated with cluster gravitational potentials are smaller than the hydrostatic mass bias and that cluster potentials could therefore be a good alternative to cluster masses in cosmological studies. Methods. Using cosmological simulations of galaxy clusters, we compute the biases in the hydrostatic mass (HE mass) and those in the gravitational potential, reconstructed from measurements at X-ray and millimeter wavelengths. In particular, we investigate the effects of the presence of substructures and of non-thermal pressure support on both the HE mass and the reconstructed potential. Results. We find that the bias in the reconstructed potential (6%) is less than that of the HE mass (13%), and that the scatter in the reconstructed potential decreases by about 35% with respect to that in the HE mass. Conclusions. This study shows that characterizing galaxy clusters by their gravitational potential is a promising alternative to using cluster masses in cluster cosmology., submitted to the journal A&A, 16 pages, 26 figures

Accounting for the triaxial shapes of galaxy clusters will become important in the context of upcoming cosmological surveys. We show that, compared to the gas density distribution, the cluster gravitational potential can be better characterised by a simple 3D model and is more robust against fluctuations. Perturbations in the gas density distribution can have a substantial influence on the derived thermodynamic properties, while cluster potentials are smooth and well-approximated by a spheroidal model. We use a statistical sample of 85 galaxy clusters from a large cosmological hydrodynamical simulation to investigate cluster shapes as a function of radius. In particular, we examine the shape of isodensity and isopotential shells and analyze how it is affected by the choice of component (gas vs. potential), substructure removal (for the gas density) and the definition of the computation domain (interior vs. shells). We find that the orientation and axis ratios of gas isodensity contours are degenerate with the presence of substructures and unstable against fluctuations. We observe that, as the derived cluster shape depends on the method used for removing the substructures, thermodynamic properties extracted from e.g. X-ray emissivity profiles suffer from this additional, often underestimated bias. In contrast, the shape reconstruction of the potential is largely unaffected by these factors and converges towards simple geometric models for both relaxed and dynamically active clusters. The observation that cluster potentials are better represented by simple geometrical models and reconstructed with a low level of systematics for both dynamically active and relaxed clusters suggests that by characterising galaxy clusters by their potential rather than by their mass, dynamically active and relaxed clusters could be combined in cosmological studies, improving statistics and lowering scatter., Comment: Updated with referee's comments, revised version submitted to A&A, 16 pages, 14 figures

In a real-world setting, the clinical response to the anti-IL-5/5R mAbs mepolizumab and benralizumab in patients with severe eosinophilic asthma is independent of co-eligibility with the anti-IgE mAb omalizumabhttps://bit.ly/2NfAitP

Freshwater biofilms can be useful indicators of water quality and offer the possibility to assess contaminant effects at the community level. The present field study examines the effects of chlor-alkali plant effluents on the community composition of biofilms grown in the Olt River (Romania) reservoirs. The relationship between ambient water quality variables and community composition alterations was explored. Amplicon sequencing revealed a significant modification of the composition of microalgal, bacterial and fungal communities in the biofilms collected in the impacted reservoirs in comparison with those living in the uncontaminated control reservoir. The abundance corrected Simpson index showed lower richness and diversity in biofilms collected in the impacted reservoirs than in the control reservoir. The biofilm bacterial communities of the impacted reservoirs were characterized by the contaminant-tolerant Cyanobacteria and Bacteroidetes, whereas microalgal communities were predominantly composed of Bacillariophyta and fungal communities of Lecanoromycetes and Paraglomycetes. A principal component analysis revealed that major contaminants present in the waste water of the chlor-alkali production plant, i.e. Na+, Ca2+, Cl- and Hg, were correlated with the alteration of biofilm community composition in the impacted reservoirs. However, the biofilm composition was also influenced by water quality variables such as NO3-, SO42-, DOC and Zn from unknown sources. The results of the present study imply that, even when below the environmental quality standards, typical contaminants of chlor-alkali plant releases may affect biofilm composition and that their impacts on the microbial biodiversity might be currently overlooked.

We present electrical transport measurements in natural graphite and highly ordered pyrolytic graphite (HOPG) comparing macroscopic samples with exfoliated nanofabricated specimen of nanometer thickness. Nano samples exhibit a very large c axis resistivity \rho_c much larger than expected from simple band theory and non monotonic temperature dependence similar to macroscopic HOPG but in stark contrast to macroscopic natural graphite. A recent model of disorder induced delocalization is consistent with the data. Micro Raman spectroscopy reveals clearly reduced disorder in exfoliated samples and HOPG as expected within the model therefore presenting further evidence for a novel paradigm of electronic transport in graphite.

The infrastructure of energy production facilities is vulnerable to natural hazards, especially in Alpine environments. The determination of risk requires the knowledge of the probability of a natural hazard event and the associated intensity and the damage potential (vulnerability), which is site and object specific. Up to now a qualitative risk assessment was standard praxis in energy production facilities, but in the past years a quantitative risk analysis gained in importance, including the determination of uncertainties. In this paper we introduce a method on how to consider ranges of object values (€) and ranges in the damage susceptibility of different types of objects in risk calculation.

Ultraviolet B (UVB, 290-320 nm) radiation initiates in vivo a dose- and wavelength-dependent down regulation of cell-mediated immunity. An action spectrum for UV-induced immunosuppression indicated that the photoreceptor for this effect is urocanic acid (UCA), which undergoes a trans to cis isomerization in the stratum corneum on UV exposure. An accumulation of evidence has supported this conclusion. However, evidence has also been presented that formation of thymine dimers in DNA is responsible for initiation of UV-induced immunosuppression. Because photobinding of UCA to DNA in vitro forming cyclobutane-type adducts has been shown, we sought to resolve this dilemma by investigating if UCA photobinds to DNA in vivo. The [14C]cis-UCA, [14C]trans-UCA or [3H]8-MOP (8-methoxypsoralen) was applied topically to BALB/c mice that were then irradiated with a dose of UV previously shown to cause systemic suppression of contact hypersensitivity. The DNA was prepared from epidermal cells by phenol extraction immediately after in vivo irradiation and bound radioactivity determined. Although photobinding of [3H]8-MOP was readily demonstrable under these conditions (0.9 nmol/mg DNA), no significant binding of either isomer of UCA to DNA (between 1.2 x 10(-3) and 2.1 x 10(-3) ng/mg DNA) could be detected. Uptake studies in keratinocytes prepared from epidermis of untreated animals indicated that [3H]8-MOP was taken up with a rate constant of 4.2 x 10(-3) pmol/s/mg protein/mumol/L. In contrast, uptake of [14C]cis-UCA was not statistically significant from zero and uptake of [14C]trans-UCA was negligible (0.8 x 10(-3) +/- 0.08 x 10(-3) pmol/s/mg protein/mumol/L). There was no significant difference between uptake of UCA isomers, but uptake of [3H]8-MOP was significantly greater than that of either UCA isomer (P0.01). These studies indicate that the photobinding of UCA to DNA does not play a role in UV-induced immunosuppression.