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In this paper, we test a method for forecasting in real-time the properties of offshore propagating tsunami waves generated by landslides, with the aim of supporting tsunami early warning systems. The method uses an inversion procedure, that takes input data measurements of water surface elevation at a point close to the tsunamigenic source. The measurements are used to correct the results of pre-computed numerical simulations, reproducing the wave field induced by different landslide scenarios. The accuracy of the method is evaluated using the results of laboratory experiments, aimed at studying tsunamis generated by landslides sliding along the flank of a circular shoreline island. The paper investigates what the optimal position is of where to measure the tsunamis, what the effects are, the accuracy of the results, and of uncertainties on the landslide scenarios. Finally, the method is successfully tested using partial input time series, simulating the behaviour of the system in real-time during the tsunami event when forecasts are updated, as the measurements become available.

Resistivity inverse problems are routinely solved in order to characterize hydrocarbon bearing formations. They often require a large number of forward problems simulations. When considering a one dimensional (1D) planarly layered media, semi-analytical methods can be employed in order to solve a single forward problem in a fraction of a second. However, in some situations, a large number of (over one million) simulations is required, preventing this method to be used as a real time (logging) alternative. In this paper, we propose a novel semi-analytical method that dramatically reduces the total computational time, so it can be employed for real time inversion. In our proposed method, we select an ad hoc basis representation for the spectral solution such that its inverse Hankel transform can be computed analytically. The proposed method requires a pre-process that is expensive when compared with a single evaluation in classical semi-analytical methods. However, subsequent evaluations can be rapidly obtained, decreasing thus the total computational time by orders of magnitude when the number of required forward simulations is large., Marie Sklodowska-Curie grant agreement No 644602 MTM2013-40824-P SEV-2013-0323 BERC 2014-2017

A linear increase with the volume of the topological susceptibility can signal spontaneous breaking of parity and time inversion, due to a nonzero vacuum expectation value of the topological charge. Such a breaking would produce a nonzero electric dipole moment of the neutron, d_n. An upper limit to d_n is derived from numerical simulations at increasing volumes., 4 pages, 3 figures, talk presented at QCD05 (Montpellier) 4-9 July

Starting in July 2011, anomalous seismicity was observed at El Hierro Island, a young oceanic island volcano. On 12 October 2011, the process led to the beginning of a submarine NW-SE fissural eruption at ~15 km from the initial earthquake loci, indicative of significant lateral magma migration. Here we conduct a multifrequency, multisensor interferometric analysis of spaceborne radar images acquired using three different satellite systems (RADARSAT-2, ENVISAT, and COSMO-SkyMed (Constellation of Small Satellites for Mediterranean Basin Observation)). The data fully captures both the pre-eruptive and coeruptive phases. Elastic modeling of the ground deformation is employed to constrain the dynamics associated with the magmatic activity. This study represents the first geodetically constrained active magmatic plumbing system model for any of the Canary Islands volcanoes, and one of the few examples of submarine volcanic activity to date. Geodetic results reveal two spatially distinct shallow (crustal) magma reservoirs, a deeper central source (9.5 ± 4.0 km), and a shallower magma reservoir at the flank of the southern rift (4.5 ± 2.0 km). The deeper source was recharged, explaining the relatively long basaltic eruption, contributing to the observed island-wide uplift processes, and validating proposed active magma underplating. The shallowest source may be an incipient reservoir that facilitates fractional crystallization as observed at other Canary Islands. Data from this eruption supports a relationship between the depth of the shallow crustal magmatic systems and the long-term magma supply rate and oceanic lithospheric age. Such a relationship implies that a factor controlling the existence/depth of shallow (crustal) magmatic systems in oceanic island volcanoes is the lithosphere thermomechanical behavior.

The short TI LGE sequence detected a significant higher number of papillary muscle infarction compared to standard LGE sequence (19/54 versus 15/54 respectively). Moreover, in these images papillary muscle infarction was appeared with more sharpness (84.2% vs 53.3%) The contrast-to-noise ratio was higher between infarcted myocardium and blood (77.9±60 vs 19.3±16, p

High-frequency measurements of atmospheric molecular hydrogen (H2) and carbon monoxide (CO) were made at an urban site in the United Kingdom (UK) from mid-December, 2008 until early March, 2009. Very few measurements of H2 exist in the urban environment, particularly within the UK, but are an essential component in the assessment of anthropogenic emissions of H2 and to a certain extent CO. These data provide detailed information on urban time-series, diurnal cycles as well as sources and sinks of both H2 and CO at urban locations. High-frequency data were found to be strongly influenced by local meteorological conditions of wind speed and temperature. Diurnal cycles were found to follow transport frequency very closely due to the sites proximity to major carriageways, consequently a strong correlation was found between H2 and CO mole fractions. Background subtracted mean and rush hour molar H2/CO emission ratios of 0.53±0.08 and 0.57±0.06 respectively, were calculated from linear fitting of data. The scatter plot of all H2 and CO data displayed an unusual two population pattern, thought to be associated with a large industrial area 85 km to the west of the site. However, the definitive source of this two branch pattern could not be fully elucidated. H2 emissions from transport in the UK were estimated to be 188±39 Gg H2/yr, with 8.1±2.3 Tg/yr of H2 produced from vehicle emissions globally. H2 and CO deposition velocities were calculated during stable night-time inversion events when a clear decay of both species was observed. CO was found to have a much higher deposition velocity than H2, 1.3±0.8×10−3 and 2.2±1.5×10−4 m s−1 (1σ) respectively, going against the law of molecular diffusivity. The source of this unusual result was investigated, however no conclusive explanation was found for increased loss of CO over H2 during stable night time inversion events.

International audience; This paper introduces a. new Light Aspiration device for in vivo Soft TIssue Characterization (LASTIC). This device is designed to be used during surgery can undergo sterilization. It provides interactive-time estimation of the elastic parameters. LASTIC is a. 3cm x. 3cm metallic cylinder divided in two compartments. The lower compartment is a. cylindrical chamber made airtight by a. glass window in which a. negative pressure can be applied. Put in contact with soft tissues it can aspirate the tissues into the chamber through a. circular aperture in its bottom side. The upper compartment is clinched onto the lower part. A. miniature digital camera is fixed inside the upper chamber focusing on the aspirated soft tissue. LASTIC is operated by applying a. range of negative pressures in the lower compartment while measuring the resulting aspirated tissue deformations with the digital camera. These measurements are used to estimate the tissue elasticity parameters by inverting a. Finite Element model of the suction experiment. In order to use LASTIC during surgical interventions a. library-based optimization process is used to provide an interactive time inversion.

Background A new fast and robust technique combing CINE imaging with a retrospectively adjustable delayed-enhancement (DE) contrast in a short breath-hold of 4 seconds was recently introduced [1]. As a benefit of this technique, DE images can be reconstructed as a CINE series for any TI contrast, which in turn could be beneficial in the evaluation of CMR images and allow for improved diagnostic accuracy. In this work, we performed an initial clinical evaluation of the technique.

Purpose To assess the diagnostic effectiveness of unenhanced-multiparametric magnetic resonance imaging (mp MRI) as an alternative to gadolinium (Gad)-enhanced MRI in the characterization of vertebral marrow infiltrative lesions. Patients and methods A prospective evaluation of fifty-six patients with suspected or untreated vertebral metastases undergoing MRI of the spine at 1.5 T was carried out. Two groups of sequences were assigned and compared for the characterization of marrow infiltrative lesions: group [A] unenhanced-mp MRI (including T1-weighted, T2-weighted, short time inversion recovery (STIR), diffusion weighted imaging (DWI) and in/opposed phase sequences) and group [B] gadolinium-enhanced MRI (including T1-weighted, T2-weighted, STIR and T1-weighted fat-suppressed gadolinium-enhanced sequence). Qualitative and quantitative image analysis was performed and compared. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for both imaging techniques were calculated. Results There was no statistical significant difference between unenhanced-multiparametric MRI and gadolinium-enhanced MRI as regards their diagnostic performance in differentiating benign from malignant vertebral marrow infiltrative lesions ( p > 0.05) with calculated sensitivity (94% vs. 97%), specificity (92% vs. 88%), positive predictive value (94% vs. 91%), negative predictive value (92% vs. 95%) and (93% vs. 93%) accuracy. Conclusion Unenhanced-multiparametric MRI is compatible with gadolinium-enhanced MRI in reliable characterization of marrow infiltrative lesions. The routine MRI protocol of cancer patients should be altered to accommodate the evolving MRI technology and cost effectively substitute the need for a gadolinium enhanced scan.