Are group- and cluster-scale dark matter halos over-concentrated?

We investigate the relationship between the halo mass, M_200, and concentration, c, for a sample of 26 group- and cluster-scale strong gravitational lenses. In contrast with previous results, we find that these systems are only ~ 0.1 dex more over-concentrated than similar-mass halos from dark matter simulations; the concentration of a halo with M_200 = 10^14 M_sun is log c = 0.78\pm0.05, while simulations of halos with this mass at similar redshifts (z ~ 0.4) predict log c ~ 0.56 - 0.71. We also find that we are unable to make informative inference on the slope of the M_200-c relation in spite of our large sample size; we note that the steep slopes found in previous studies tend to follow the slope in the covariance between M_200 and c, indicating that these results may be measuring the scatter in the data rather than the intrinsic signal. Furthermore, we conclude that our inability to constrain the M_200-c slope is due to a limited range of halo masses, as determined by explicitly modelling our halo mass distribution, and we suggest that other studies may be producing biased results by using an incorrect distribution for their halo masses.Comment: 8 pages; accepted to MNRA

A rapid review of communication strategies for physical activity guidelines and physical activity promotion: A review of worldwide strategies

BACKGROUND: To support the strategy development for communication of the updated physical activity (PA) guidelines, the UK Chief Medical Officers’ Expert Panel for Communication was created. METHODS: To help inform this process a rapid review was performed to identify and describe how other nations are communicating their PA guidelines and PA generally. Elements of the Health enhancing physical activity (HEPA) policy audit tool (PAT) created by the World Health Organization (WHO) were used to investigate all 195 countries. RESULTS: Seventy-seven countries had their own guidelines, 53 used the WHO guidelines, and for 65 countries no guidelines could be found. For the communication, 27 countries used infographics, 56 had government policies/documents, and 11 used a mass media campaign. Only 6 of these had been evaluated. Although many countries used infographics, there were no associated evaluations. As such any future communication strategies should incorporate an evaluation. Mass media campaigns had the strongest evidence base, proving to be an effective strategy, particularly when incorporating aspects of social marketing. CONCLUSION: This review provides an insight into strategies countries worldwide have taken to communicate PA guidelines and PA promotion. These should be carefully considered when deciding how best to communicate and promote PA guidelines

Surface topography of precursors Cu-Zn-Sn electrochemically deposited on Mo/glass and Mo-foil

The paper discusses the possibility of constructing thin-film solar cells based on non-toxic and abundant Cu2ZnSnSe4 components (CZTSe) obtained by electrochemical deposition on Ta-foil substrates with subsequent selenization. Foil substrates open up new possibilities for application of flexible thin-film solar cells. Atomic force microscopy and scanning electron microscopy combined with energy dispersive spectrometry of secondary electrons were employed for the investigation of thin films topography. В статье обсуждается возможность создания тонкопленочных солнечных элементов на основе нетоксичных и распространенных компонентов Cu2ZnSnSe4 (CZTSe), полученных электрохимическим осаждением на подложки из Ta-фольги с последующей селенизацией. Подложки из фольги открывают новые возможности применения гибких тонкопленочных солнечных элементов. Для исследования топографии тонких пленок использовались атомно-силовая микроскопия и сканирующая электронная микроскопия в сочетании с энергодисперсионной спектрометрией вторичных электронов

Calibration and sensitivity of the Virgo detector during its second science run

The Virgo detector is a kilometer-length interferometer for gravitational wave detection located near Pisa (Italy). During its second science run (VSR2) in 2009, six months of data were accumulated with a sensitivity close to its design. In this paper, the methods used to determine the parameters for sensitivity estimation and gravitational wave reconstruction are described. The main quantities to be calibrated are the frequency response of the mirror actuation and the sensing of the output power. Focus is also put on their absolute timing. The monitoring of the calibration data as well as the parameter estimation with independent techniques are discussed to provide an estimation of the calibration uncertainties. Finally, the estimation of the Virgo sensitivity in the frequency-domain is described and typical sensitivities measured during VSR2 are shown.Comment: 30 pages, 23 figures, 1 table. Published in Classical and Quantum Gravity (CQG), Corrigendum include