Assessing the performance of protective winter covers for outdoor marble statuary: pilot investigation

Outdoor statuary in gardens and parks in temperate climates has a tradition of being covered during the winter, to protect against external conditions. There has been little scientific study of the environmental protection that different types of covers provide. This paper examines environmental conditions provided by a range of covers used to protect marble statuary at three sites in the UK. The protection required depends upon the condition of the marble. Although statues closely wrapped and with a layer of insulation provide good protection, this needs to be considered against the potential physical damage of close wrapping a fragile deteriorated surface

HESS-II expected performance in the tens of GeV

International audienceBy the end of 2009 the four-telescopes-HESS-system will be upgraded to HESS-II with a new telescope with a 600 m2 mirror area and a very high resolution camera. HESS-II will allow to lower the energy threshold from 100 GeV to about 30 GeV and enhance the HESS sensitivity. Therefore AGNs at higher redshift could be detected and searches for new classes of very high energy gamma-ray emitters (pulsars, microquasars, GRB, and dark matter candidates) will also be possible. The evaluation of the instrument performance is presented in term of sensitivity, energy and angular resolutions, based on Monte Carlo simulation, using a multivariate analysis

In situ characterisation of readhesion treatments for ceiling paintings using unilateral NMR

Ceiling and wall paintings pose significant challenges for historic house management due to their position at the interface between the environment and the building. Tight restrictions to modifications on built heritage prevent total control of the environment, resulting in temperature and humidity fluctuations. Different hygrothermal responses within the wall painting stratigraphy frequently lead to fracturing and lifting of paint layers, necessitating remedial conservation to readhere areas of detachment. Assessing the success of readhesion interventions is difficult due to the hidden nature of the treatment and, often, limited access. This paper presents comparative results of two different adhesive treatments employed during the conservation of the baroque ceiling painting in the Queen's Staircase at Hampton Court Palace, analysed with unilateral nuclear magnetic resonance (NMR). This non-invasive technique enabled monitoring of the adhesive systems, based on Jun Funori and BEVA® 371 adhesives, up to a depth of 3,500 μm into the ceiling by providing specially resolved proton density profiles before and after treatment. The results offer a unique and pertinent assessment of treatment areas within a strictly limited timeframe. It is shown that the solvent carrier leaves the system within 24 hours and that the ultimate deposition of the adhesive can be identified

Inducible liver-specific knockdown of protein tyrosine phosphatase 1B improves glucose and lipid homeostasis in adult mice.

AIMS/HYPOTHESIS Protein tyrosine phosphatase 1B (PTP1B) is a key negative regulator of insulin signalling. Hepatic PTP1B deficiency, using the Alb-Cre promoter to drive Ptp1b deletion from birth in mice, improves glucose homeostasis, insulin sensitivity and lipid metabolism. The aim of this study was to investigate the therapeutic potential of decreasing liver PTP1B levels in obese and insulin-resistant adult mice. METHODS Inducible Ptp1b liver-specific knockout mice were generated using SA-Cre-ER(T2) mice crossed with Ptp1b floxed (Ptp1b(fl/fl)) mice. Mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity and insulin resistance. Tamoxifen was administered in the HFD to induce liver-specific deletion of Ptp1b (SA-Ptp1b(-/-) mice). Body weight, glucose homeostasis, lipid homeostasis, serum adipokines, insulin signalling and endoplasmic reticulum (ER) stress were examined. RESULTS Despite no significant change in body weight relative to HFD-fed Ptp1b(fl/fl) control mice, HFD-fed SA-Ptp1b(-/-) mice exhibited a reversal of glucose intolerance as determined by improved glucose and pyruvate tolerance tests, decreased fed and fasting blood glucose and insulin levels, lower HOMA of insulin resistance, circulating leptin, serum and liver triacylglycerols, serum NEFA and decreased HFD-induced ER stress. This was associated with decreased glycogen synthase, eukaryotic translation initiation factor-2α kinase 3, eukaryotic initiation factor 2α and c-Jun NH2-terminal kinase 2 phosphorylation, and decreased expression of Pepck. CONCLUSIONS/INTERPRETATION Inducible liver-specific PTP1B knockdown reverses glucose intolerance and improves lipid homeostasis in HFD-fed obese and insulin-resistant adult mice. This suggests that knockdown of liver PTP1B in individuals who are already obese/insulin resistant may have relatively rapid, beneficial therapeutic effects

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

HESS-II expected performance in the tens of GeV

International audienceBy the end of 2009 the four-telescopes-HESS-system will be upgraded to HESS-II with a new telescope with a 600 m2 mirror area and a very high resolution camera. HESS-II will allow to lower the energy threshold from 100 GeV to about 30 GeV and enhance the HESS sensitivity. Therefore AGNs at higher redshift could be detected and searches for new classes of very high energy gamma-ray emitters (pulsars, microquasars, GRB, and dark matter candidates) will also be possible. The evaluation of the instrument performance is presented in term of sensitivity, energy and angular resolutions, based on Monte Carlo simulation, using a multivariate analysis

Dark matter searches with H.E.S.S.: nearby dwarf galaxies and IMBH mini-spikes

International audienceWIMP pair annihilations produce high energy gamma-rays in the final state, which can be detected by Imaging Atmospheric Cherenkov Telescopes such as the H.E.S.S. array. We focus in this contribution on searches towards dwarf galaxies and mini-spikes around intermediate mass black holes (IMBHs) in the Galactic halo. H.E.S.S. observations towards the nearby dwarf galaxies Sagittarius and Canis Major are presented. Using realistic modellings for the dark matter (DM) density profiles, constraints on the velocity-weighted annihilation cross section sigmav of DM particles are derived in the framework of Supersymmetric and Kaluza-Klein models. A search for DM mini-spikes around IMBHs is described as well as constraints on the particle physics parameters

Ammando 61, 62 , F. de Palma 45

See paper for full list of authors - 13 pages, 9 figures, accepted for publication in A&AInternational audienceThe addition of a 28 m Cherenkov telescope (CT5) to the H.E.S.S. array extended the experiment's sensitivity to lower energies. The lowest energy threshold is obtained using monoscopic analysis of data taken with CT5, providing access to gamma-ray energies below 100 GeV. Such an extension of the instrument's energy range is particularly beneficial for studies of Active Galactic Nuclei with soft spectra, as expected for those at a redshift > 0.5. The high-frequency peaked BL Lac objects PKS 2155-304 (z = 0.116) and PG 1553+113 (0.43 100 GeV interpreted as being due to interactions with the extragalactic background light (EBL). Multiple observational campaigns of PKS 2155-304 and PG 1553+113 were conducted during 2013 and 2014 using the full H.E.S.S. II instrument. A monoscopic analysis of the data taken with the new CT5 telescope was developed along with an investigation into the systematic uncertainties on the spectral parameters. The energy spectra of PKS 2155-304 and PG 1553+113 were reconstructed down to energies of 80 GeV for PKS 2155-304, which transits near zenith, and 110 GeV for the more northern PG 1553+113. The measured spectra, well fitted in both cases by a log-parabola spectral model (with a 5.0 sigma statistical preference for non-zero curvature for PKS 2155-304 and 4.5 sigma for PG 1553+113), were found consistent with spectra derived from contemporaneous Fermi-LAT data, indicating a sharp break in the observed spectra of both sources at E ~ 100 GeV. When corrected for EBL absorption, the intrinsic H.E.S.S. II mono and Fermi-LAT spectrum of PKS 2155-304 was found to show significant curvature. For PG 1553+113, however, no significant detection of curvature in the intrinsic spectrum could be found within statistical and systematic uncertainties