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Objective: The objectives of our study were to analyze the influence of age on the survival of patients with RAIR-DTC and to determine their prognostic factors according to age. Methods: This single-center, retrospective study enrolled 155 patients diagnosed with RAIR-DTC. The primary end point was overall survival (OS) according to different cutoff (45, 55, 65, 75 years). Secondary endpoints were progression free survival (PFS) and prognostic factors in patients under and over 65 years. Results: Median OS after RAIR diagnosis was 8.2 years (95% IC: 5.3–9.6). There was no difference according to age with a 65 (P = 0.47) and 55 years old cutoff (P = 0.28). Median OS improved significantly before 45 years old (P = 0.0043). After 75 years old, median OS significantly decreased (P = 0.0008). Median PFS was 2.1 years (95% CI: 0.8–3) in patients < 65 years old, and 1 year in patients ≥ 65 years old (95% CI: 0.8–1.55) with no statistical difference (P = 0.22). There was no impact of age on PFS with any cutoff. In both groups, progressive disease despite 131I treatment reduced OS. In patients < 65 years old, an interval of less than 3 years between the initial diagnosis and the diagnosis of RAIR metastatic disease was predictive of poor survival. In patients > 65 years old, the presence of a mediastinum metastasis was a significant factor for mortality (HR: 4.55, 95% CI: 2.27–9.09). Conclusion: In RAIR-DTC patients, a cut-off age of 65 years old was not a significant predictive factor of survival. Fortyfive and 75-years-old cutoff were predictive for OS but not PFS. [ABSTRACT FROM AUTHOR]

Measuring and modelling the permeability of tight rocks remains a challenging task. In addition to the traditional sources of errors that affect more permeable formations (e.g. sample selection, non-representative specimens, disturbance introduced during sample acquisition and preparation), tight rocks can be particularly prone to solid–fluid interactions and thus more sensitive to the methods, procedures and techniques used to measure permeability. To address this problem, it is desirable to collect, for a single material, measurements obtained by different methods and pore fluids. For that purpose, a benchmarking exercise involving 24 laboratories was organized for measuring and modelling the permeability of a single low-permeability material, the Grimsel granodiorite. The objectives of the benchmark were: (i) to compare the results for a given method, (ii) to compare the results between different methods, (iii) to analyse the accuracy of each method, (iv) to study the influence of experimental conditions (especially the nature of pore fluid), (v) to discuss the relevance of indirect methods and models and finally (vi) to suggest good practice for low-permeability measurements. To complement the data set of permeability measurements presented in a companion paper, we focus here on (i) quantitative analysis of microstructures and pore size distribution, (ii) permeability modelling and (iii) complementary measurements of permeability anisotropy and poroelastic parameters. Broad ion beam—scanning electron microscopy, micro-computerized tomography, mercury injection capillary pressure (MICP) and nuclear magnetic resonance (NMR) methods were used to characterize the microstructures and provided the input parameters for permeability modelling. Several models were used: (i) basic statistical models, (ii) 3-D pore network and effective medium models, (iii) percolation model using MICP data and (iv) free-fluid model using NMR data. The models were generally successful in predicting the actual range of measured permeability. Statistical models overestimate the permeability because they do not adequately account for the heterogeneity of the crack network. Pore network and effective medium models provide additional constraints on crack parameters such as aspect ratio, aperture, density and connectivity. MICP and advanced microscopy techniques are very useful tools providing important input data for permeability estimation. Permeability measured—orthogonal to foliation is lower that—parallel to foliation. Combining the experimental and modelling results provide a unique and rich data set. [ABSTRACT FROM AUTHOR]

Measuring the permeability of tight rocks remains a challenging task. In addition to the traditional sources of errors that affect more permeable formations (e.g. sample selection, non-representative specimens, disturbance introduced during sample acquisition and preparation), tight rocks can be particularly prone to solid–fluid interactions and thus more sensitive to the methods, procedures and techniques used to measure permeability. To address this problem, it is desirable to collect, for a single material, measurements obtained by different methods and pore-fluids. For that purpose a collaborative benchmarking exercise involving 24 laboratories was organized for measuring the permeability of a single low permeability material, the Grimsel granodiorite, at a common effective confining pressure (5 MPa). The objectives of the benchmark were: (i) to compare the results for a given method, (ii) to compare the results between different methods, (iii) to analyze the accuracy of each method, (iv) to study the influence of experimental conditions (especially the nature of pore fluid), (v) to discuss the relevance of indirect methods and models and finally (vi) to suggest good practice for low permeability measurements. In total 39 measurements were collected that allowed us to discuss the influence of (i) pore-fluid, (ii) measurement method, (iii) sample size and (iv) pressure sensitivity. Discarding some outliers from the bulk data set (4 out of 39) an average permeability of 1.11 × 10−18 m² with a standard deviation of 0.57 × 10−18 m² was obtained. The most striking result was the large difference in permeability for gas measurements compared to liquid measurements. Regardless of the method used, gas permeability was higher than liquid permeability by a factor approximately 2 (k gas = 1.28 × 10−18 m² compared to k liquid = 0.65 × 10−18 m²). Possible explanations are that (i) liquid permeability was underestimated due to fluid-rock interactions (ii) gas permeability was overestimated due to insufficient correction for gas slippage and/or (iii) gases and liquids do not probe exactly the same porous networks. The analysis of Knudsen numbers shows that the gas permeability measurements were performed in conditions for which the Klinkenberg correction is sufficient. Smaller samples had a larger scatter of permeability values, suggesting that their volume were below the Representative Elementary Volume. The pressure dependence of permeability was studied by some of the participating teams in the range 1–30 MPa and could be fitted to an exponential law k  =  ko.exp(– γP eff) with γ  = 0.093 MPa−1. Good practice rules for measuring permeability in tight materials are also provided. [ABSTRACT FROM AUTHOR]

We present the analysis of rotational and translational ground motions from earthquakes recorded during October-November 2016, in association with the Central Italy seismic sequence. We use co-located measurements of the vertical ground rotation rate from a large ring laser gyroscope and the three components of ground velocity from a broad-band seismometer. Both instruments are positioned in a deep underground environment, within the Gran Sasso National Laboratories of the Istituto Nazionale di Fisica Nucleare. We collected dozens of events spanning the 3.5-5.9 magnitude range and epicentral distances between 30 and 70 km. This data set constitutes an unprecedented observation of the vertical rotational motions associated with an intense seismic sequence at local distance. Under the plane-wave approximation we process the data set in order to get an experimental estimation of the events backazimuth. Peak values of rotation rate (PRR) and horizontal acceleration (PGA) are markedly correlated, according to a scaling constant which is consistent with previous measurements from different earthquake sequences. We used a prediction model in use for Italy to calculate the expected PGA at the recording site, obtaining consequently predictions for PRR. Within the modelling uncertainties, predicted rotations are consistent with the observed ones, suggesting the possibility of establishing specific attenuation models for ground rotations, like the scaling of peak velocity and peak acceleration in empirical ground-motion prediction relationships. In a second step, after identifying the direction of the incoming wavefield, we extract phase-velocity data using the spectral ratio of the translational and rotational components. This analysis is performed over time windows associated with the P-coda, S-coda and Lg phase. Results are consistent with independent estimates of shear wave velocities in the shallow crust of the Central Apennines. [ABSTRACT FROM AUTHOR]

We present observations of cross coupled spheroidal modes in the Earth's free oscillation spectrum recorded by the vertical component G-ring laser (Geodetical Station Wettzell) of the 2011 Mw 9.0 Tohoku-Oki earthquake. In an attempt to determine which are the mechanisms responsible for spheroidal energy in a vertical axes rotational spectra, we first rule out instrumental effects as well as the effect of local heterogeneity. Secondly, we carry out simulations of an ideal rotational sensor taking into account the effects of the Earth's rotation, its hydrostatic ellipticity and structural heterogeneity, which results in a good fit to the data. Simulations considering each effect separately are performed in order to evaluate the sensitivity of rotational motions to various phenomena compared to traditional translation measurements. [ABSTRACT FROM AUTHOR]

We report in this paper an original analysis of microseismic events (MSEs) induced by an excavation operation in the clay environment of the Mont Terri underground rock laboratory. In order to identify the MSEs with confidence, we develop a restrictive but efficient multistep method for filtering the recorded events. We deduce the spatial distribution and processes associated with the excavation-induced damage from the spatial location and focal mechanisms of the MSEs. We observe an asymmetric geometry of the excavation damaged zone around the excavated gallery, without notable microseismic activity in the sandy facies sidewall, in contrast with the shaly facies sidewall where a first burst of events is recorded, followed by two smaller bursts: one locates ahead of the excavation front and is associated with a dominant double-couple component, suggesting bedding plane reworking, that is, shear fracture mode, and the MSEs of the other cluster inside the shaly sidewall of the gallery, with a dominant compensated linear vector dipole component, suggesting extensive cracking. We identify and discuss four major factors that seem to control the MSEs source mechanisms: lithology, geometry of the geological features, gallery orientation and direction of the main compressive stress. [ABSTRACT FROM PUBLISHER]

Uniaxial and triaxial compression experiments were performed on oolitic iron ores to investigate damage processes. Most of these experiments included four indirect measurements of damage evolution, that is, P-wave velocity and maximum amplitude received during pulse transmission experiments, elastic properties (apparent Young´s modulus and apparent Poisson´s ratio) and acoustic emission (AE) monitoring. The mechanical behaviour deduced from strain measurements is dilatant for some samples and non-dilatant for the other samples. However, variations in elastic properties indicate damage processes for all samples. AE source mechanism analysis shows two different microscopic damage processes: (1) for dilatant rock, the development of axial extensive microcracks as well as their interaction and coalescence lead to the formation of shear macroscopic discontinuities; (2) for non-dilatant oolitic iron ore, both compressive and shear micromechanisms take place and interact with macroscopic fractures. A particular consistency between the four types of measurements employed was observed. [ABSTRACT FROM AUTHOR]

The 2002 seismicity of Mt Hochstaufen, SE Germany, is characterized by several swarm-type earthquake sequences that follow above-average rainfall events. First investigations have recently provided indication, that the rain events triggered this swarm-type activity. We present a detailed relocation of the 2002 seismicity, which is composed of (1) cluster analysis, (2) multievent semi-automatic phase repicking, (3) probabilistic location in a pseudo-3-D velocity model with topography and (4) master event relocation. Furthermore, focal mechanisms of selected events are derived by taking into account the first-motion polarities of P, SV and SH waves. We introduce a simple methodology to test the stability and estimate the variance of the focal mechanisms solutions. Location uncertainties of less than 100 m were achieved. The hypocentres are mainly concentrated between 1000 m above and 4000 m below sea level and aligned on two planes, which, however, cannot be associated with geological structures with reasonable certainty. Swarm-type activity follows above-average rain events and shows a depth migration of hypocentres over time. Evidence that the rain events triggered the earthquake swarms is reported by Hainzl et al. on basis of our relocation. The derived focal mechanisms seem to indicate an influence of the Saalachtal Fault Zone on the stress regime of the study area. [ABSTRACT FROM AUTHOR]