Role of a Phase: Change Moho in Stabilization and Preservation of the Southern Uralide Orogen, Russia

Geophysical (URSEIS experiment) and geological data from the Southern Uralides of central Russia provide the basis for a geodynamic model involving eclogitization of the Uralian crustal root in Late Triassic to Early Jurassic time as a mechanism for stabilization and preservation of this Paleozoic orogen. The crustal structure of the orogen implies eastward subduction of the East European continental crust, and balanced restoration implies a significant volume of crust (comprised of ~70% European crust, and ~30% accreted terranes) was carried to sub-Moho depths of up to 70 km. The lack of a clearly defined near-vertical incidence reflection Moho corroborated by coincident wide-angle reflection data suggest that the Moho is a sub-horizontal gradational boundary at ~50--53 km depth beneath the axis of the Southern Uralides. Previous modeling of a subdued (-50 mgal) regional Bouguer gravity minimum across the orogen suggests a subsurface load that is interpreted here as substantiation for a metamorphic phasechange of the lower crust to mantle-like eclogite facies rocks. Timing of eclogitization appears to be constrained by (1) superposition of a nearly flat Moho across the Paleozoic Uralian orogenic fabric, and (2) zircon and apatite fission-track minimum ages of 180--200 Ma, marking an upper age limit to cooling of rocks exposed at the surface, and, implicitly, to significant uplift and erosion in the Southern Uralides. The proposed eclogitization of the Southern Uralian root zone may have led to an isostatically balanced system with subdued topography, and thereby presumably served to stabilize and preserve the orogenic structure

Seismogeological Features of the Crust in Romania

The Romanian area consists of old consolidated units of pre-Alpine age (the Moesian, Moldavian and Scythian platforms) and Alpine orogenic units (the Carpathian arc and North-Dobrudjan orogen). General seismogeological peculiarities of the pre-Alpine tectonic units are presented, as well as some structural characteristics of the Transylvanian Basin and the Pannonian Depression. Both shallow and deep seismic reflection/refraction data as well as log information and some potential field data were used for the investigation of the crustal structure. The varibility in the seismogeological pattern and crustal thickness shown by the different tectonic units is due to the differences in structure and lithology as well as to differences in crustal age. Some general characteristics are presented as an overall seismogeological image

HEPATORENAL SYNDROME: A REVIEW

Hepatorenal syndrome (HRS) is defined as a functional renal failure in patients with liver disease that features morphologically intact kidneys, where regulatory mechanisms have minimized glomerular filtration and maximized tubular resorption and urine concentration. The syndrome occurs almost exclusively in patients with ascites. Type 1 HRS develops as a consequence of a severe reduction of effective circulating volume due to both an extreme splanchnic arterial vasodilatation and a reduction of cardiac output. Type 2 HRS is characterized by a stable or slowly progressive renal failure so that its main clinical consequence is not acute renal failure, but refractory ascites, and its impact on prognosis is less negative. Liver transplantation is the most appropriate therapeutic method, nevertheless, only a few patients can receive it. The first line treatment includes terlipressin plus albumin. Renal function recovery can be achieved in less than 50% of patients and a considerable decrease in renal function may reoccur even in patients who have been responding to therapy over the short term. Other therapies include transjugular intrahepatic portosystemic shunts (TIPS), dialysis and peritoneovenous shunts which are most commonly done when patients are awaiting a liver transplant or when there is the possibility of improvement in liver function

Probing Tectonic Topography in the Aftermath of Continental Convergence in Central Europe

Continental topography is at the interface of processes taking place at depth in the Earth,at its surface,and above it.Topography influences society, not only in terms of slow processes of landscape change and earthquakes,but also in terms of how it affects climate.The Pannonian Basin–Carpathian Orogen System in Central and Eastern Europe represents a key natural laboratory for the development of a new generation of models for ongoing orogeny and its effect on continental topography development (Figure 1).This system comprises some of the best documented sedimentary basins in the world,located within the Alpine orogenic belt, at the transition between the western European lithosphere and the East European Craton. It includes one of the most active seismic zones in Europe,with intermediate depth (50–220 km) mantle earthquakes of significant magnitude occurring in a geographically restricted area in the Vrancea zone of southeastern Romania

Precambrian Moho Offset and Tectonic Stability of the East European Platform from the URSEIS Deep Seismic Profile

Deep seismic reflection data from the 1995 Urals Seismic Experiment and Integrated Studies (URSEIS) transect of the Southern Urals document a distinct ∼5 km vertical offset of the Moho beneath the Uralian foreland, here named the Makarovo fault zone. This offset does not disrupt the overlying Riphean sedimentary section, nor does it correlate with any major surface lineaments or known Phanerozoic subduction features. It is thus interpreted to be an Archean or Early Proterozoic fault zone (possibly a terrane boundary) that disrupts an even older Moho. Most important is the implication that this structure and the Moho it offsets were not significantly modified by two subsequent cycles of continental collision that affected this region, the Baikalian (700–570 Ma) and the late Paleozoic Uralian (350–230 Ma) orogenic phases. Similarly, the pronounced reflectivity of the Moho beneath the Uralian foreland must also be a Precambrian signature, not a young feature, as would be implied by certain recent thermo-rheological and reflectivity models that associate a reflective lower crust and Moho with areas that underwent pronounced synorogenic or postorogenic collapse. The Makarovo fault zone provides yet another demonstration that relicts of ancient tectonic processes can survive for long periods of time in the lower crust, and that the Moho can be a key marker horizon in delineating the tectonic evolution of the lithosphere

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)