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If femoral blood is not available at autopsy, toxicological analyses, in particular blood ethanol measurements, are carried out on cardiac blood. This is known to be subject to major redistribution. We aimed to determine whether subclavian blood can be equated with a peripheral blood sample and could be used if femoral blood is not available. The study was based on 50 medicolegal autopsies in which we compared ethanol concentrations between subclavian blood, the different heart blood compartments (right and left cardiac blood), and femoral blood. Mechanisms that could lead to variations in concentration, i.e., postmortem redistribution and/or endogenous production, were also taken into account in interpreting the results. Ethanol concentrations were determined by headspace gas chromatography with a flame ionization detector. In each case, we recorded the circumstances of death, resuscitation attempts if any, degree of putrefaction, chest or abdominal trauma, and/or inhalation of gastric fluid in the airways. Ethanol concentrations in subclavian blood were found to be close to those in peripheral blood (p = 0.948) and were not influenced by the degree of putrefaction (r = 0.017, p = 0.904), gastric ethanol concentration (r = -0.011, p = 0.940), inhalation of gastric contents in the airways (p = 0.461), or cardiac resuscitation attempts (p = 0.368). We discuss the possible explanations for these findings and stress the value of sampling subclavian blood when femoral blood is not obtainable at autopsy.

It is increasingly acknowledged that climate change is influencing terrestrial ecosystems by increased drought and rainfall intensities. Soil microbes are key drivers of many processes in terrestrial systems and rely on water in soil pores to fulfill their life cycles and functions. However, little is known on how drought and rainfall fluctuations, which affect the composition and structure of microbial communities, persist once original moisture conditions have been restored. Here, we study how simulated short-term drying and re-wetting events shape the community composition of soil fungi and prokaryotes. In a mesocosm experiment, soil was exposed to an extreme drought, then re-wetted to optimal moisture (50% WHC, water holding capacity) or to saturation level (100% WHC). Composition, community structure and diversity of microbes were measured by sequencing ITS and 16S rRNA gene amplicons 3 weeks after original moisture content had been restored. Drying and extreme re-wetting decreased richness of microbial communities, but not evenness. Abundance changes were observed in only 8% of prokaryote OTUs, and 25% of fungal OTUs, whereas all other OTUs did not differ between drying and re-wetting treatments. Two specific legacy response groups (LRGs) were observed for both prokaryotes and fungi. OTUs belonging to the first LRG decreased in relative abundance in soil with a history of drought, whereas OTUs that increased in soil with a history of drought formed a second LRG. These microbial responses were spread among different phyla. Drought appeared to be more important for the microbial community composition than the following extreme re-wetting. 16S profiles were correlated with both inorganic N concentration and basal respiration and ITS profiles correlated with fungal biomass. We conclude that a drying and/or an extreme re-wetting history can persist in soil microbial communities via specific response groups composed of members with broad phylogenetic origins, with possible functional consequences on soil processes and plant species. As a large fraction of OTUs responding to drying and re-wetting belonged to the rare biosphere, our results suggest that low abundant microbial species are potentially important for ecosystem responses to extreme weather events.

Abstract The Antarctic and Greenland ice contains an almost direct record of past atmospheric CH 4 . The record over the last 200 years reveals a spectacular 150% increase of the CH 4 atmospheric mixing ratio since pre-industrial times. At the scale of a glacial-interglacial cycle the record shows a remarkable correlation with climatic changes, with high (low) CH 4 levels during warm (cold) periods. A striking feature of the glacial-interglacial CH 4 record is the presence of large and abrupt (at the scale of a century or less) changes during the last glaciation and glacial-interglacial transition. The classical interpretation for the origin of CH 4 changes prior to the industrial era involves mainly the wetland source. In the context of gas hydrates the question is to know whether the past ice-core record contains fingerprints of catastrophic hydrate release (CHR). We currently conclude that the available record shows no evidence for CHR but additional ice-core analyses are necessary to reach a more definitive conclusion.

The reason why low-to-moderate alcohol drinking is associated with reduced cardiovascular mortality is not elucidated. While data suggested that ethanol drinking may have a protective effect on global cardiac ischemia, the effect of chronic low dose ethanol drinking (CLEthD) on myocardial infarct size has not been evaluated in a model of regional ischemia. Using an isolated rat heart model to exclude the effect of various in vivo confounders, we have studied the effect of CLEthD on infarct size (IS) and left ventricular function after 30 min of regional ischemia and 120 min of reperfusion. The effect of CLEthD was compared with ischemic preconditioning (IPC) and protein kinase C (PKC) isoforms were analysed in the myocardium before the 30-min ischemia. Ethanol-fed rats received 9% (v/v) ethanol in their drinking water for 7 weeks. Four groups of rats were studied: (1) control, (2) ethanol, (3) control + IPC, (4) ethanol + IPC. Compared with controls (59 +/- 10), IS (as percent of risk zone) was smaller in the ethanol (39 +/- 6) and IPC (31 +/- 8) groups (both p < 0.05). Combination of ethanol and IPC in the same rats further decreased IS (-46% vs. ethanol, p < 0.05). PKC analyses did not show sustained isoform translocation in that model. These data indicate that chronic low dose ethanol drinking actually induces in the rat heart a chronic protective state that is independent from an effect on the traditional (lipid and coagulation) risk factors. Further studies are required to elucidate the mechanisms of that protection.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data- taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1+/-0.9 ��m and a relative momentum resolution ��p/p = (4.83+/-0.16) \times 10-4 GeV-1 \times pT have been measured for high momentum tracks. 34 pages, 25 figures