High-resolution Rayleigh-wave velocity maps of central Europe from a dense ambient-noise data set

We present a new database of surface wave group and phase-velocity dispersion curves derived from seismic ambient noise, cross-correlating continuous seismic recordings from the Swiss Network, the German Regional Seismological Network (GRSN), the Italian national broad-band network operated by the Istituto Nazionale di Geosica e Vulcanologia (INGV). To increase the aperture of the station array, additional measurements from the Mediterranean Very Broad-band Seismographic Network (MedNet), the Austrian Central Institute for Meteorology and Geodynamics (ZAMG), the French, Bulgarian, Hungarian, Romanian and Greek stations obtained through Orfeus are also included. The ambient noise, we are using to assemble our database, was recorded at the above-mentioned stations between 2006 January and 2006 December. Correlating continuous signal recorded at pairs of stations, allows to extract coherent surface wave signal travelling between the two stations. Usually the ambient-noise cross-correlation technique allows to have informations at periods of 30 s or shorter. By expanding the database of noise correlations, we seek to increase the resolution of the central Europe crustal model. We invert the resulting data sets of group and phase velocities associated with 8-35 s Rayleigh waves, to determine 2-D group and phase-velocity maps of the European region. Inversions are conducted by means of a 2-D linearized tomographic inversion algorithm. The generally good agreement of our models with previous studies and good correlation of well-resolved velocity anomalies with geological features, such as sedimentary basins, crustal roots and mountain ranges, documents the effectiveness of our approac

A new absolute arrival time data set for Europe

The main aim of this study is to create a data set of accurate absolute arrival times for stations in Europe which do not report to the International Seismological Centre (ISC). Waveforms were obtained from data centres and temporary experiments and a semi-automatic picking method was applied to determine absolute arrival times for P and S phases. 85 000 arrival times were picked whose distribution of residuals shows generally low standard deviations on the order of 0.5-0.7 s. Furthermore, mean teleseismic station residuals reflect the properties of the underlying crust and uppermost mantle. Comparison to ISC data for matching event-station-phase combinations also confirms the good quality of the new absolute arrival time picks. Most importantly, this data set complements the ISC data as it fills regional data coverage gaps in Europ

Shallow subduction beneath Italy

This paper presents a velocity model of the Italian (central Mediterranean) lithosphere in unprecedented detail. The model is derived by inverting a set of 166,000 Pg and Pn seismic wave arrival times, restricted to the highest-quality data available. The tomographic images reveal the geometry of the subduction-collision system between the European, Adriatic, and Tyrrhenian plates, over a larger volume and with finer resolution than previous studies. We find two arcs of low-Vp anomalies running along the Alps and the Apennines, describing the collision zones of underthrusting continental lithospheres. Our results suggest that in the Apennines, a significant portion of the crust has been subducted below the mountain belt. From the velocity model we can also infer thermal softening of the crustal wedge above the subducting Adriatic plate. In the Tyrrhenian back-arc region, strong and extensive low-Vp anomalies depict upwelling asthenospheric material. The tomographic images also allow us to trace the boundary between the Adriatic and the Tyrrhenian plates at Moho depth, revealing some tears in the Adriatic-Ionian subducting lithosphere. The complex lithospheric structure described by this study is the result of a long evolution; the heterogeneities of continental margins, lithospheric underthrusting, and plate indentation have led to subduction variations, slab tears, and asthenospheric upwelling at the present day. The high-resolution model provided here greatly improves our understanding of the central Mediterranean’s structural puzzle. The results of this study can also shed light on the evolution of other regions experiencing both oceanic and continental subduction

The fidelity of DNA synthesis by yeast DNA polymerase zeta alone and with accessory proteins

DNA polymerase zeta (pol z) participates in several DNA transactions in eukaryotic cells that increase spontaneous and damage-induced mutagenesis. To better understand this central role in mutagenesis in vivo, here we report the fidelity of DNA synthesis in vitro by yeast pol z alone and with RFC, PCNA and RPA. Overall, the accessory proteins have little effect on the fidelity of pol z. Pol z is relatively accurate for single base insertion/deletion errors. However, the average base substitution fidelity of pol z is substantially lower than that of homologous B family pols a, d and «. Pol z is particularly error prone for substitutions in specific sequence con-texts and generates multiple single base errors clustered in short patches at a rate that is unprece-dented in comparison with other polymerases. The unique error specificity of pol z in vitro is consistent with Pol z-dependent mutagenic specificity reported in vivo. This fact, combined with the high rate of single base substitution errors and complex muta-tions observed here, indicates that pol z contributes to mutagenesis in vivo not only by extending mismatches made by other polymerases, but also by directly generating its own mismatches and then extending them

I-Move towards monitoring seasonal and pandemic influenza vaccine effectiveness: lessons learnt from a pilot multi-centric case-control study in europe, 2008-9

Within I-MOVE (European programme to monitor seasonal and pandemic influenza vaccine effectiveness (IVE)) five countries conducted IVE pilot case-control studies in 2008-9. One hundred and sixty sentinel general practitioners (GP) swabbed all elderly consulting for influenza-like illness (ILI). Influenza confirmed cases were compared to influenza negative controls. We conducted a pooled analysis to obtain a summary IVE in the age group of >or=65 years. We measured IVE in each study and assessed heterogeneity between studies qualitatively and using the I2 index. We used a one-stage pooled model with study as a fixed effect. We adjusted estimates for age-group, sex, chronic diseases, smoking, functional status, previous influenza vaccinations and previous hospitalisations. The pooled analysis included 138 cases and 189 test-negative controls. There was no statistical heterogeneity (I2=0) between studies but ILI case definition, previous hospitalisations and functional status were slightly different. The adjusted IVE was 59.1% (95% CI: 15.3-80.3%). IVE was 65.4% (95% CI: 15.6-85.8%) in the 65-74, 59.6% (95% CI: -72.6 -90.6%) in the age group of >or=75 and 56.4% (95% CI: -0.2-81.3%) for A(H3). Pooled analysis is feasible among European studies. The variables definitions need further standardisation. Larger sample sizes are needed to achieve greater precision for subgroup analysis. For 2009-10, I-MOVE will extend the study to obtain early IVE estimates in groups targeted for pandemic H1N1 influenza vaccination.European Centre for Disease Prevention and Control (ECDC

Segmented Hellenic slab rollback driving Aegean deformation and seismicity

The NE dipping slab of the Hellenic subduction is imaged in unprecedented detail using teleseismic receiver function analysis on a dense 2-D seismic array. Mapping of slab geometry for over 300 km along strike and down to 100 km depth reveals a segmentation into dipping panels by along-dip faults. Resolved intermediate-depth seismicity commonly attributed to dehydration embrittlement is shown to be clustered along these faults. Large earthquakes occurrence within the upper and lower plate and at the interplate megathrust boundary show a striking correlation with the slab faults suggesting high mechanical coupling between the two plates. Our results imply that the general slab rollback occurs here in a differential piecewise manner imposing its specific stress and deformation pattern onto the overriding Aegean plate

NGO Legitimacy: Four Models

The aim of this paper is to examine NGOs’ legitimacy in the context of global politics. In order to yield a better understanding of NGOs’ legitimacy at the international level it is important to examine how their legitimacy claims are evaluated. This paper proposes dividing the literature into four models based on the theoretical and analytical approaches to their legitimacy claims: the market model, social change model, new institutionalism model and the critical model. The legitimacy criteria generated by the models are significantly different in their analytical scope of how one is to assess the role of NGOs operating as political actors contributing to democracy. The paper argues that the models present incomplete, and sometimes conflicting, views of NGOs’ legitimacy and that this poses a legitimacy dilemma for those assessing the political agency of NGOs in world politics. The paper concludes that only by approaching their legitimacy holistically can the democratic role of NGOs be explored and analysed in the context of world politics

Hepatic Mitochondrial Alteration in CD-1 Mice Associated with Prenatal Exposures to Low Doses of Perfluorooctanoic Acid (PFOA)

Perfluorooctanoic acid (PFOA) is a perfluoroalkyl acid primarily used as an industrial surfactant. It persists in the environment and has been linked to potentially toxic and/or carcinogenic effects in animals and people. As a known activator of peroxisome proliferator-activated receptors (PPARs), PFOA exposure can induce defects in fatty acid oxidation, lipid transport, and inflammation. Here, pregnant CD-1 mice were orally gavaged with 0, 0.01, 0.1, 0.3 and 1 mg/kg of PFOA from gestation days (GD) 1 through 17. On postnatal day (PND) 21, histopathologic changes in the livers of offspring included hepatocellular hypertrophy and periportal inflammation that increased in severity by PND 91 in an apparent dose-dependent response. Transmission electron microscopy (TEM) of selected liver sections from PND 91 mice revealed PFOA-induced cellular damage and mitochondrial abnormalities with no evidence of peroxisome proliferation. Within hypertrophied hepatocytes, mitochondria were not only increased in number, but also exhibited altered morphologies suggestive of increased and/or uncontrolled fission and fusion reactions. These findings suggest that peroxisome proliferation is not a component of PFOA-induced hepatic toxicity in animals that are prenatally exposed to low doses of PFOA