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Deep seismic studies have revealed that low-velocity zones mainly occurred in the continental lithosphere at the depth of 100–150 km. Their origin has not been clearly explained yet. The article demonstrates the possible scale of Vp changes in crystalline rocks of different composition. The conclusions were made on the basis of the comprehensive analysis of the experimental data obtained by the authors. The compressional wave velocities in the temperature range from 20 to 800 °C, both in dry conditions (at pressure of 600 MPa) and in the presence of aqueous fluid (at pressure of 300 MPa) were measured. It is shown that the most significant decrease of velocities (by ~ 3 km/s) in the temperature range of 400–700 °C, corresponding to the deep waveguides of the lithospheric mantle, occurs under water pressure in ultramafic rocks enriched by olivine (dunites). Such decrease is due to rock structure changes caused by olivine serpentinization reactions. It is assumed that serpentinization and/or formation of similar hydrous minerals, which are stable in a wide range of PT-conditions in olivine-rich mantle rocks due to the influence of deep fluids, may cause low-velocities zones in the upper mantle at depths of about 100 km.

Lithologic interpretations of the earth crust from seismic wave velocities are non-unique so that inferences about composition can not be drawn. In order to evaluate how elastic properties of rock materials are controlled by lithology at in situ pressures and temperatures, compressional (Vp), shear wave velocities (Vs) and velocity anisotropy of crustal rocks were measured at conditions of greater depth. The first part deals with the interdependence of elastic wave propagation and the physical and lithological parameters. In the second part data from laboratory seismic measurements and theoretical calculations are used to interpret (1) a shallow seismic reflection line (SE Finland) and (2) a refraction profile of a deep crust (Central China). The comparison of the calculated velocities with the experimentally-derived in situ velocities of the Finnish crustal rocks give hints that microcracks have an important bearing on the in situ seismic velocities, velocity anisotropy and the reflectivity observed at relative shallow depth. The coupling of the experimentally-derived in situ velocities of P- and S-wave and corresponding Poisson's ratios of relevant exhumed high-grade metamorphic crustal rocks from Central China with respective data from seismic refraction profiling provided a key for the lithologic interpretation of a deep seismic crustal structure.

Objective To investigate the differences in incidence, time course and outcome of primary versus secondary intra-abdominal hypertension (IAH), and to evaluate IAH as an independent risk factor of mortality in a presumable risk population of critically ill patients. Design Prospective observational study. Setting General intensive care unit of a university hospital. Patients A total of 257 mechanically ventilated patients at presumable risk for the development of IAH were studied during their ICU stay and followed up for 90-day survival. Interventions Repeated measurements of intra-abdominal pressure (IAP). Measurements and results IAP was measured intermittently, via bladder. IAH (sustained or repeated IAP ≥ 12 mmHg) developed in 95 patients (37.0%). Primary IAH was observed in 60 and secondary IAH in 35 patients. Patients with secondary IAH demonstrated a significant increase of mean IAP during the first three days (mean ΔIAP was 2.2 ± 4.7 mmHg), whilst IAP decreased (mean ΔIAP −1.1 ± 3.7 mmHg) in the patients with primary IAH. The patients with IAH had a significantly higher ICU- (37.9 vs. 19.1%; P  = 0.001), 28-day (48.4 vs. 27.8%, P  = 0.001), and 90-day mortality (53.7 vs. 35.8%, P  = 0.004) compared to the patients without the syndrome. Patients with secondary IAH had a significantly higher ICU mortality than patients with primary IAH ( P  = 0.032). Development of IAH was identified as an independent risk factor for death (OR 2.52; 95% CI 1.23–5.14). Conclusions Secondary IAH is less frequent, has a different time course and worse outcome than primary IAH. Development of IAH during ICU period is an independent risk factor for death.

In the geologic record, the quartz c -axis patterns are widely adopted in the investigation of crystallographic preferred orientations (CPO) of naturally deformed rocks. To this aim, in the present work, four different methods for measuring quartz c -axis orientations in naturally sheared rocks were applied and compared: the classical universal stage technique, the computer-integrated polarization microscopy method (CIP), the time-of-flight (TOF) neutron diffraction analysis , and the electron backscatter diffraction (EBSD). Microstructural analysis and CPO patterns of quartz, together with the ones obtained for feldspars and micas in mylonitic granitoid rocks, have been then considered to solve structural and geological questions related to the Montalto crustal scale shear zone (Calabria, southern Italy). Results obtained by applying the different techniques are discussed, and the advantages as well as limitations of each method are highlighted. Importantly, our findings suggest that patterns obtained by means of different techniques are quite similar. In particular, for such mylonites, a subsimple shear (40% simple shear vs 60% pure shear) by shape analysis of porphyroclasts was inferred. A general tendency of an asymmetric c -maximum near to the Z direction (normal to foliation) suggesting dominant basal slip, consistent with fabric patterns related to dynamically recrystallization under greenschist facies, is recognized. Rhombohedral slip was likely active as documented by pole figures of positive and negative rhombs (TOF), which reveal also potential mechanical Dauphiné twinning. Results showed that the most complete CPO characterization on deformed rocks is given by the TOF (from which also other quartz crystallographic axes can be obtained as well as various mineral phases may be investigated). However, this use is restricted by the fact that (a) there are very few TOF facilities around the world and (b) there is loss of any domainal reference, since TOF is a bulk type analysis. EBSD is a widely used technique, which allows an excellent microstructural control of the user covering a good amount of investigated grains. CIP and US are not expensive techniques with respect the other kind of investigations and even if they might be considered obsolete and/or time-consuming, they have the advantage to provide a fine and grain by grain “first round” inspection on the investigated rock fabric.

At the southern boundary of the Rhodope Massif, NE Greece, the Kavala Shear Zone (KSZ) represents an example of the Eastern Mediterranean deep-seated extensional tectonic setting. During Miocene time, extensional deformation favoured syntectonic emplacement and subsequent exhumation of plutonic bodies. This paper deals with the strain-related changes in macroscopic, geochemical and microstructural properties of the lithotypes collected along the KSZ, comprising granitoids from the pluton, aplitic dykes and host rock gneisses. Moreover, we investigated the evolution of seismic anisotropy on a suite of granitoid mylonites as a result of progressive strain. Isotropic compressional and shear wave velocities (Vp, Vs) and densities calculated from modal proportions and single-crystal elastic properties at given pressure-temperature (P-T) conditions are compared to respective experimental data including the directional dependence (anisotropy) of wave velocities. Compared to the calculated isotropic velocities, which are similar for all of the investigated mylonites (average values: Vp approximately 5.87 km s-1, Vs approximately 3.4 km s-1, Vp/Vs = 1.73 and density = 2.65 g cm-3), the seismic measurements give evidence for marked P-wave velocity anisotropy up to 6.92% (at 400 MPa) in the most deformed rock due to marked microstructural changes with progressive strain, as highlighted by the alignment of mica, chlorite minerals and quartz ribbons. The highest P- and S-wave velocities are parallel to the foliation plane and lowest normal to the foliation plane. Importantly, Vp remains constant within the foliation with progressive strain, but decreases normal to foliation. The potential of the observed seismic anisotropy of the KSZ mylonites with respect to detectable seismic reflections is briefly discussed.

Crustal structures of nine broad tectonic units in China, except the Tarim craton, are derived from 18 seismic refraction profiles including 12 geoscience transects. Abundances of 63 major, trace and rare earth elements in the upper crust in East China are estimated. The estimates are based on sampling of 11 451 individual rock samples over an area of 950 000 km2, from which 905 large composite samples are prepared and analyzed by 13 methods. The middle, lower and total crust compositions of East China are also estimated from studies of exposed crustal cross sections and granulite xenoliths and by correlation of seismic data with lithologies. All the tectonic units except the Tarim craton and the Qinling orogen show a four-layered crustal structure, consisting of the upper, middle, upper lower, and lowermost crusts. P-wave velocities of the bulk lower crust and total crust are 6.8–7.0 and 6:4–6.5 km/s, respectively. They are slower by 0.2–0.4 km/s than the global averages. The bulk lower crust is suggested to be intermediate with 58% SiO2 in East China. The results contrast with generally accepted global models of mafic lower crusi. The proposed total crust composition in East China is also more evolved than previous estimates and characterized by SiO2=64%, a significant negative Eu anomaly (Eu/Eu* = 0.80), deficits in Sr and transition metals, a near-arc magma La/Nd ratio (3.0), and a calculatedμ(238U/204Pb) value of 5. In addition, it has the following ratios of element pairs exhibiting similar compatibility, which are identical or close to the primitive mantle values: Zr/Hf=37, Nb/Ta=17.5, Ba/Th=87, K/Pb=0.12x104, Rb/Cs=25, Ba/Rb=8.94, Sn/Sm=0.31, Se/Cd=1.64, La/ As=10.3, Ce/Sb=271, Pb/Bi=57, Rb/TI=177, Er/Ag=52, Cu/Au=3.2×104, Sm/Mo=7.5, Nd/W=40, CI/Li=10.8, F/Nd=21.9, and La/B=1.8.

Background. High volumes of haemofiltration are used in septic patients to control systemic inflammation and improve patient outcomes. We aimed to clarify if extended intermittent high volume online haemodiafiltration (HVHDF) influences patient haemodynamics and cytokines profile and/or has effect upon sublingual microcirculation in critically ill septic shock patients. Methods. Main haemodynamic and clinical variables and concentrations of cytokines were evaluated before and after HVHDF in 19 patients with septic shock requiring renal replacement therapy due to acute kidney injury. Sublingual microcirculation was assessed in 9 patients. Results. The mean (SD) time of HVHDF was 9.4 (1.8) hours. The median convective volume was 123 mL/kg/h. The mean (SD) dose of norepinephrine required to maintain mean arterial pressure at the target range of 70–80 mmHg decreased from 0.40 (0.43) μg/kg/min to 0.28 (0.33) μg/kg/min (p = 0.009). No significant changes in the measured cytokines or microcirculatory parameters were observed before and after HVHDF. Conclusions. The single-centre study suggests that extended HVHDF results in decrease of norepinephrine requirement in patients with septic shock. Haemodynamic improvement was not associated with decrease in circulating cytokine levels, and sublingual microcirculation was well preserved.

Recently, it was proposed that solubleintercellular adhesion molecule (sICAM)-1 plasma levels may allowsubgroup identification of patients at risk for cardiovascularcomplications during sepsis. However, the impact of preexistingcoronary artery disease (CAD) on these results has not yet been tested. The aim of this study was to investigate whether plasma levels of adhesion molecules, nitric oxide, and cytokines differ between septicpatients with or with out preexisting CAD. Prospective study. Surgical ICU. Forty-four septic patients, 24 of whom met thecriteria of CAD. Hemodynamic measurementswere performed and blood samples were taken with in 12 h afteronset of sepsis (early sepsis) and again 72 h thereafter (latesepsis). Soluble adhesion molecules and cytokines were determined usingcommercially available enzyme-linked immunosorbent assay kits, cyclicguanosinomonophosphate (cGMP) by competitive radioimmunoassay, and nitrite/nitrate photometrically by Griess reaction. In CAD patients, sICAM-1 (p < 0.02) wassignificantly elevated in early and late sepsis, whereas solubleendothelial-linked adhesion molecule (sE-selectin; p < 0.01) and cGMP (p < 0.03) were only increased in late sepsis. Oxygenconsumption did not significantly differ between groups. Oxygendelivery and mixed venous oxygen saturation during early and latesepsis were significantly diminished and the oxygen extraction ratiosignificantly increased in the CAD group (p < 0.05). Increased endothelial injury may be indicatedby the elevated levels of sICAM-1, sE-selectin, and cGMP in septicpatients with preexisting CAD. These parameters, however, failed toserve as predictors for unknown CAD or chances for survival in earlysepsis.

Laboratory measurements of combined P- and S-wave-velocities of eclogite from the Dabie-Sulu ultrahigh pressure metamorphic belt and from literature data show a significant increase of Poisson’s ratio of eclogite with its intrinsic water content H2O+ and thus the degree of hydration. Unaltered eclogites with H2O+<1.0% have an average Poisson’s ratio between 0.24 and 0.25, which is identical to that calculated from single crystal elastic properties but lower than the averages (0.27±0.02) of measurements compiled by previous studies. Thus, the Poisson’s ratio of unaltered eclogites is considerably lower than that of lower crustal mafic granulite and upper mantle peridotite. The lower crust and upper mantle of the Dabie ultrahigh pressure metamorphic belt, the northern and southern parts of the Tibetan Plateau as well as the central Andes, where eclogite may have formed during Mesozoic and Cenozoic tectonism, are characterized by the Poisson’s ratio >0.26. This, together with their normal upper mantle P-wave velocities, implies that eclogites are no longer an important component of the present-day lower crust and upper mantle of these subduction-collision belts. Combined with age constraints on eclogite-facies metamorphism and subsequent exhumation, this in turn suggests that the interval from formation to delamination of eclogites is confined to a very short period of <15 Ma.