Improving Global Radial Anisotropy Tomography: The Importance of Simultaneously Inverting for Crustal and Mantle Structure

Observed seismic anisotropy gives the most direct information on mantle flow, but it is challenging to image it robustly at global scales. Difficulties in separating crustal from mantle structures in particular can have a strong influence on the imaging. Here we carry out several resolution tests using both real and synthetic data, which show that unconstrained crustal structure can strongly contaminate retrieved radial anisotropy at 100–150 km depth. To efficiently reduce crustal effects, we perform whole‐mantle radially anisotropic tomographic inversions including crustal thickness perturbations as model parameters. Our data set includes short‐period group velocity data, which are sensitive to shallow structure. We perform a series of tests that highlight the advantages of our approach and show that to properly constrain thin oceanic crust in global radially anisotropic inversions, group velocity data with wave periods of at least T∼20  s or shorter are required. Our Moho perturbation model shows thicker crust along subduction zones and beneath the Ontong Java plateau in the southwestern Pacific than in the global crustal model CRUST2.0. These features agree well with other crustal models as well as with refraction survey data and tectonic features in these regions

Parasites gastro-intestinaux d'antilopes et de buffles (Syncerus caffer brachyceros) du ranch de gibier de Nazinga au Burkina Faso

Gastro-intestinal parasites of antelopes and buffalos (Syncerus caffer brachyceros) from the Nazinga game ranch in Burkina Faso. Parasitological survey done on the digestive tracts of antelopes [roans (Hippotragus equinus koba), hartebeests (Alcelaphus buselaphus major), defassa waterbucks (Kobus ellipsiprymnus defassa), oribis (Ourebia ourebi quadriscopa)] and buffalos (Syncerus caffer brachyceros) from the Nazinga game ranch in Burkina Faso allowed the identification of gastrointestinal parasites and the estimation of their prevalence and load. Nine different nematode species and three cestode species were found. Females and larvae of Cooperia were not identified up to the species level and were recognized as Cooperia spp. The nematode species found were: Haemonchus contortus, Trichostrongylus axei, Cooperia curticei, Cooperia spatulata, Skrjabinema sp., Trichostrongylus colubriformis, Trichuris ovis, Bunostomum phlebotomum, and Oesophagostomum sp. Cestodes’ species were: Moniezia expansa, Avitellina centripunctata, and Stilesia globipunctata. It was also noted without a thorough investigation the presence of Setaria labiato-papillosa in the abdominal cavity and paramphistomes in the rumen. In spite of the presence of parasites on the antelopes and buffalos, their killing out percentages (47.5 to 54.7%) indicated a good physical status

Resolution of rupture directivity in weak events: 1-D versus 2-D source parameterizations for the 2011, M-w 4.6 and 5.2 Lorca earthquakes, Spain

Resolving robust source parameters of small-moderate magnitude earthquakes is still a challenge in seismology. We infer directivity from apparent source time functions (ASTFs) at regional distance and quantify the associated uncertainties. ASTFs are used for (i) modeling a propagating 1-D line source from the duration data and (ii) inverting the 2-D slip distribution from the full signals. Slip inversion is performed through a Popperian scheme, where random trial models are either falsified on account of large misfit, or else become members of the solution set of the inverse problem. We assess the resolution of rupture directivity representing centroid shifts from the solution set in a rose diagram. Using as example an event with well-studied rupture directivity, the 2011 Mw 5.2 Lorca (Spain) earthquake, 1-D and 2-D parameterizations yield similar estimates for direction (N213°E and N220°E, respectively) and asymmetry (67:33, 65:35) of rupture propagation, as well as rupture length (2.1 km, 2.7 km) and speed (3.5 km/s, 3.25 km/s). The high rupture velocity ≥ 90% vS may be held primarily responsible for the strong directivity effect of this earthquake. We show that inversion of apparent source durations is intrinsically unable to resolve highly asymmetric bilateral ruptures, while inversion of full ASTFs misses part of the signal's complexity, suggesting the presence of deconvolution artifacts. We extend the analysis to the Mw 4.6 foreshock of the Lorca earthquake, inferring similar directivity parameters and slip pattern as for the mainshock. The rupture toward SW of both earthquakes suggests that this direction could be inherent to the fault segment

Extended fault inversion with random slipmaps: a resolution test for the 2012 Mw 7.6 Nicoya, Costa Rica earthquake

Inversions for the full slip distribution of earthquakes provide detailed models of earthquake sources, but stability and non-uniqueness of the inversions is a major concern. The problem is underdetermined in any realistic setting, and significantly different slip distributions may translate to fairly similar seismograms. In such circumstances, inverting for a single best model may become overly dependent on the details of the procedure. Instead, we propose to perform extended fault inversion trough falsification. We generate a representative set of heterogeneous slipmaps, compute their forward predictions, and falsify inappropriate trial models that do not reproduce the data within a reasonable level of mismodelling. The remainder of surviving trial models forms our set of coequal solutions. The solution set may contain only members with similar slip distributions, or else uncover some fundamental ambiguity such as, for example, different patterns of main slip patches. For a feasibility study, we use teleseismic body wave recordings from the 2012 September 5 Nicoya, Costa Rica earthquake, although the inversion strategy can be applied to any type of seismic, geodetic or tsunami data for which we can handle the forward problem. We generate 10 000 pseudo-random, heterogeneous slip distributions assuming a von Karman autocorrelation function, keeping the rake angle, rupture velocity and slip velocity function fixed. The slip distribution of the 2012 Nicoya earthquake turns out to be relatively well constrained from 50 teleseismic waveforms. Two hundred fifty-two slip models with normalized L1-fit within 5 per cent from the global minimum from our solution set. They consistently show a single dominant slip patch around the hypocentre. Uncertainties are related to the details of the slip maximum, including the amount of peak slip (2–3.5 m), as well as the characteristics of peripheral slip below 1 m. Synthetic tests suggest that slip patterns such as Nicoya may be a fortunate case, while it may be more difficult to unambiguously reconstruct more distributed slip from teleseismic data

Ellipticity of Rayleigh waves in basin and hard-rock sites in Northern Italy

We measure ellipticity of teleseismic Rayleigh waves at 95 seismic stations in Northern Italy, for wave period between 10 and 110 s, using an automatic technique and a large volume of high-quality seismic recordings from over 500 global earthquakes that occurred in 2008–2014. Northern Italy includes a wide range of crustal structures, from the wide and deep Po Plain sedimentary basin to outcropping sedimentary and crystalline rocks in the Northern Apennines and Alps. It thus provides an excellent case for studying the influence of shallow earth structure on polarization of surface waves. The ellipticity measurements show excellent spatial correlation with geological features in the region, such as high ellipticity associated with regions of low seismic velocity in the Po Plain and low ellipticity values in faster, hard rock regions in the Alps and Apennine mountains. Moreover, the observed ellipticity values also relate to the thickness of the basement, as highlighted by observed differences beneath the Alps and the Apennines. Comparison between observations and predicted ellipticity from a reference crustal model of the region show substantial fit, particularly for T ∼ 38 s data. Discrepancy for shorter wave period suggests that slight modifications of the model are needed, and that the ellipticity measurements could help to better constrain the shallow crustal structure of the region. Predictions for the Po Plain are larger than the observations by a factor of four or more and transition from retrograde to prograde Rayleigh wave motion at the surface for periods of T ∼ 10–13 s is predicted for seismic stations in the plain. Analysis of corresponding real data indicates a possible detection of teleseismic prograde particle motion, but the weak teleseismic earthquake signals are mixed with ambient noise signals at the predicted, short, transition periods. Detection of the period of polarity inversion from the joint analysis of earthquake and ambient noise ellipticity measurements may provide further, stringent, constraints on the structure of sedimentary basins

Crustal structure of northern Italy from the ellipticity of Rayleigh waves

Northern Italy is a diverse geological region, including the wide and thick Po Plain sedimentary basin, which is bounded by the Alps and the Apennines. The seismically slow shallow structure of the Po Plain is difficult to retrieve with classical seismic measurements such as surface wave dispersion, yet the detailed structure of the region greatly affects seismic wave propagation and hence seismic ground shaking. Here we invert Rayleigh wave ellipticity measurements in the period range 10–60 s for 95 stations in northern Italy using a fully non linear approach to constrain vertical vS,vPvS,vP and density profiles of the crust beneath each station. The ellipticity of Rayleigh wave ground motion is primarily sensitive to shear-wave velocity beneath the recording station, which reduces along-path contamination effects. We use the 3D layering structure in MAMBo, a previous model based on a compilation of geological and geophysical information for the Po Plain and surrounding regions of northern Italy, and employ ellipticity data to constrain vS,vPvS,vP and density within its layers. We show that ellipticity data from ballistic teleseismic wave trains alone constrain the crustal structure well. This leads to MAMBo-E, an updated seismic model of the region’s crust that inherits information available from previous seismic prospection and geological studies, while fitting new seismic data well. MAMBo-E brings new insights into lateral heterogeneity in the region’s subsurface. Compared to MAMBo, it shows overall faster seismic anomalies in the region’s Quaternary, Pliocene and Oligo-Miocene layers and better delineates the seismic structures of the Po Plain at depth. Two low velocity regions are mapped in the Mesozoic layer in the western and eastern parts of the Plain, which seem to correspond to the Monferrato sedimentary basin and to the Ferrara-Romagna thrust system, respectively

High-quality lowest-frequency normal mode strain observations at the Black Forest Observatory (SW-Germany) and comparison with horizontal broad-band seismometer data and synthetics

We present spectra concentrating on the lowest-frequency normal modes of the Earth obtained from records of the invar-wire strainmeters and STS-1 broad-band seismometers located in the Black Forest Observatory, Germany after the disastrous earthquakes off the NW coast of Sumatra in 2004 and off the coast near Tohoku, Japan in 2011. We compare the spectra to ones obtained from synthetic seismograms computed using a mode summation technique for an anelastic, elliptical, rotating, spherically symmetric Earth model. The synthetics include strain–strain-coupling effects by using coupling coefficients obtained from comparisons between Earth tide signals recorded by the strainmeters and synthetic tidal records. We show that for the low-frequency toroidal and spheroidal modes up to 1 mHz, the strainmeters produce better signal-to-noise ratios than the broad-band horizontal seismometers. Overall, the comparison with the synthetics is satisfactory but not as good as for vertical accelerations. In particular, we demonstrate the high quality of the strainmeter data by showing the Coriolis splitting of toroidal modes for the first time in individual records, the first clear observation of the singlet 2S0/1 and the detection of the fundamental radial mode 0S0 with good signal-to-noise ratio and with a strain amplitude of 10^−11. We also identify the latter mode in a record of the Isabella strainmeter after the great Chilean quake in 1960, the detection of which was missed by the original studies

Renal hemodynamic changes and renal functional reserve in children with type I diabetes mellitus

Increased glomerular filtration rate (GFR) has been implicated in the development of diabetic nephropathy. Large normal interindividual variations of GFR hamper the diagnosis of renal hemodynamic alterations. We examined renal functional reserve (RFR) in children with type 1 diabetes mellitus to assess whether hyperfiltration occurs. The renal hemodynamic response following dopamine infusion was examined in 51 normoalbuminuric diabetic children (7.7 +/- 3.6 years) with a mean duration of diabetes of 6.2 years and compared them with 34 controls. Mean baseline GFR in diabetic children did not differ from the control population (130.7 +/- 22.9 vs. 124.8 +/- 25 ml/min per 1.73 m(2) stop), whereas renal plasma flow was significantly lower (463.7 +/- 103.9 vs. 587.2 +/- 105 ml/min per 1.73 m(2) , p < 0.001), and filtration fraction was increased (29 +/- 8 vs. 21 +/- 2%, p < 0.001), compared with controls. The mean RFR was lower (p < 0.001) than in control subjects (-0.77 +/- 23 vs. 21 +/- 8 ml/min per 1.73 m(2) stop). This study documents an increased filtration fraction and reduced or absent RFR in children with type 1 diabetes mellitus in the stage before apparent nephropathy. GFR values were within normal range. Although the reduced RFR and increased filtration fraction indicate the presence of hemodynamic changes, their relevance to the development of hyperfiltration and subsequent diabetic nephropathy remains unknown

Quantitative projections of a quality measure: Performance of a complex task

AbstractComplex data series that arise during interaction between humans (operators) and advanced technology in a controlled and realistic setting have been explored. The purpose is to obtain quantitative measures that reflect quality in task performance: on a ship simulator, nine crews have solved the same exercise, and detailed maneuvering histories have been logged. There are many degrees of freedom, some of them connected to the fact that the vessels may be freely moved in any direction. To compare maneuvering histories, several measures were used: the time needed to reach the position of operation, the integrated angle between the hull direction and the direction of motion, and the extent of movement when the vessel is to be manually kept in a fixed position. These measures are expected to reflect quality in performance. We have also obtained expert quality evaluations of the crews. The quantitative measures and the expert evaluations, taken together, allow a ranking of crew performance. However, except for time and integrated angle, there is no correlation between the individual measures. This may indicate that complex situations with social and man–machine interactions need complex measures of quality in task performance. In general terms, we have established a context-dependent and flexible framework with quantitative measures in contact with a social-science concept that is hard to define. This approach may be useful for other (qualitative) concepts in social science that contain important information on the society

RBMS3 at 3p24 inhibits nasopharyngeal carcinoma development via inhibiting cell proliferation, angiogenesis, and inducing apoptosis.

Deletion of the short arm of chromosome 3 is one of the most frequent genetic alterations in many solid tumors including nasopharyngeal carcinoma (NPC), suggesting the existence of one or more tumor suppressor genes (TSGs) within the frequently deleted region. A putative TSG RBMS3 (RNA binding motif, single stranded interacting protein 3), located at 3p24-p23, has been identified in our previous study. Here, we reported that downregulation of RBMS3 was detected in 3/3 NPC cell lines and 13/15 (86.7%) primary NPC tissues. Functional studies using both overexpression and suppression systems demonstrated that RBMS3 has a strong tumor suppressive role in NPC. The tumor suppressive mechanism of RBMS3 was associated with its role in cell cycle arrest at the G1/S checkpoint by upregulating p53 and p21, downregulating cyclin E and CDK2, and the subsequent inhibition of Rb-ser780. Further analysis demonstrated that RBMS3 had a pro-apoptotic role in a mitochondrial-dependent manner via activation of caspase-9 and PARP. Finally, RBMS3 inhibited microvessel formation, which may be mediated by down-regulation of MMP2 and β-catenin and inactivation of its downstream targets, including cyclin-D1, c-Myc, MMP7, and MMP9. Taken together, our findings define a function for RBMS3 as an important tumor suppressor gene in NPC.published_or_final_versio