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The Izu-Bonin subduction zone is a subduction system formed in early Eocene. The structure of the subduction zone becomes complicated with the evolution of the surrounding plate motion, and many aspects are still unkown or ambiguous. The geodynamic implications are further investigated in related to published seismic observations and geochemical characters of the Izu-Bonin subduction zone. As indicated by seismic tomography and epicentral distributions, the dip angle of the plate beneath the segment to the south of 29°–30°N (the southern Izu-Bonin) is much steeper than the northern one (the northern Izu-Bonin). Deep focus events in the southern segment extend to the depth of ∼600 km, whereas in the northern section deep events just terminate at 420–450 km. Particularly, tomographic images show an obvious boundary between the northern and southern Izu-Bonin at depths of 150–600 km neglected in the previous studies. The northern and southern segments are even separated by a wide range of low-velocity anomaly in P and S wave tomography at 380 km and 450 km depths. In this depth range, three events near 30°N are characterized by strike-slip mechanisms with slab parallel σ 1 and horizontally north-south trending σ 3 , which differ with the typical down-dip compression mechanisms for neighboring events. These events could be attributed to an abrupt change of the morphology and movement of the slab in the transition segment between the northern and southern Izu-Bonin. Indicated by the focal mechanisms, the northern and southern Izu-Bonin exhibits an inhomogeneous stress field, which is closely related to age differences of the downgoing slab. Because of the reheating process, the thermal age of the Pacific plate entering the Izu-Bonin trench in the past 10 Ma, is only 60–90 ± 20 Ma, along with the younger plate subducting in the northern segment. The seismic anisotropy implies that mantle wedge flow orientation is between the motion direction of the Pacific plate and trench strike, which may be caused by the viscous coupling to the subducting plate and along-trench N-S shearing. The NE splitting direction oblique or perpendicular to the NW-NNW movement of the Pacific plate beneath the transition segment results from the “tearing” of the slab, which is also confirmed by the slab-related velocity anomalies, a sharp change in the dip angle of the Wadati-Benioff zone, the tectonic stress characteristics and along-arc variations of Sr-Nd-Pb isotope ratios in the transition segment. [ABSTRACT FROM AUTHOR]

The principal objective of this paper is to understand the gas migration process and the structures of mud volcanoes in the central Black Sea. Multichannel seismic lines were acquired across 6 mud volcanoes in the central Black Sea: MSU, Yuzhmorgeologiya, Malyshev, Kornev, Goncharov and Vassoevitch. Based on a high resolution seismic processing, we analyzed acoustic anomalies and studied near-surface sediment structures of these mud volcanoes. Four types of pathways for gas and fluid migration and three types of gas reservoirs were recognized. A regional “Bottom Simulating Reflection” (BSR) seems to be absent in most parts of the study area, however a clear BSR was observed in one of the seismic profiles. The free gas migrating upwards along these pathways were sealed by gas hydrates or fine-grained sediments in the gas hydrate stability zone. Four seismic units were separated according to a suggested age model and identified seismic facies. Combining with the possible sedimentary processes of the central Black Sea, we try to reveal the active mechanism of these mud volcanoes. These mud volcanoes reveal two to three major active stages. These active stages might be related to distinct sea level falls, which seem to be one of the main trigger factors of the mud volcano eruptions in the central Black Sea. A structural model for the MSU mud volcano was presented with respect to mechanisms of gas migration and the origin of the gas. [ABSTRACT FROM AUTHOR]

Coronary artery interventional therapy is a clinically effective minimally invasive surgery for coronary artery disease. Extracting effective coronary vascular structures from coronary angiography videos is essential for the safe navigation of coronary interventional equipment and for the doctor to observe the location of the lesion. This paper proposes a new semi 3D architecture that uses the temporal information of video to segment coronary arteries from angiography video. We combine the 3D U-Net and 2D U-Net through a dimension conversion layer and a context extracting module. The input of the 3D encoder is a set of coronary video sequences. After the extracted three-dimensional features pass through the dimension conversion layer and the context information extraction module, the valuable features are input into the 2D decoder module. Finally, a clearer and more complete coronary is extracted to help the doctor to observe the vascular status better. We tested this method and the comparison methods on the coronary angiography video data set we made before. We can see from the experimental results that even in coronary angiography video sequences with poor quality, our method can achieve better results than the other methods. The accuracy of our results can reach 98.60%, which shows that in the vessel video segmentation task, the extraction of temporal information is helpful to extract a more complete vascular structure. [ABSTRACT FROM AUTHOR]

To investigate the lithospheric structure and deformation of the Tibetan Plateau, we present thermo-rheological models for two transects across the southeastern Tibetan Plateau (SE Tibet), showing strong lateral heterogeneity. The geodynamic implications are also investigated in relation to GPS motions, seismic anisotropy, seismicity distribution and crustal isostatic state. The unmatched pattern between Pms and SKS splittings which even intersect at right angles to the south of 26°N, suggests the crust-mantle decoupling. Constrained by a brittle load-bearing layer at the uppermost mantle beneath the Indochina block, the decoupling may occur below the uppermost mantle. The strong crust beneath the South China plate and Indochina block implied by the seismicity distribution, has two thick brittle load-bearing layers, indicating a coupled system. The crust beneath the Emeishan large igneous province (ELIP) also has two brittle load-bearing layers, but the brittle deformation is restricted to the topmost 10 km of the upper and lower crust. Only one brittle load-bearing layer resides in the upper crust in the other part of the Chuandian block. Combining with GPS and Pms splitting, we can infer that the weak crust with seismicity restricted into the depth of <30 km beneath the Chuandian block becomes decoupled. The heterogeneous rheological behavior under SE Tibet is further supported by different crustal isostatic states among the blocks. Through the comparison with observations in the central-northern Tibetan Plateau and Chuandian block, we suggest that the layers with aqueous fluids and (or) partial melting are distributed only in some place/channels of the weak middle-lower crust. [ABSTRACT FROM AUTHOR]

Diabetes is a chronic non-communicable disease whose incidence continues to grow rapidly, and it is one of the most serious and critical public health problems. Diabetes complications, especially atherosclerosis-related chronic vascular complications, are a serious threat to human life and health. Growing evidence suggests that dipeptidyl peptidase 4 (DPP4) inhibitors, beyond their role in improving glycemic control, are helpful in ameliorating endothelial dysfunction in humans and animal models of T2DM. In fact, DPP4 inhibitors have been shown by successive studies to play a protective effect against vascular complications. On one hand, in addition to their hypoglycemic effects, DPP4 inhibitors participate in the control of atherosclerotic risk factors by regulating blood lipids and lowering blood pressure. On the other hand, DPP4 inhibitors exert anti-atherosclerotic effects directly through multiple mechanisms, including improving endothelial cell dysfunction, increasing circulating endothelial progenitor cell (EPCs) levels, regulating mononuclear macrophages and smooth muscle cells, inhibiting inflammation and oxidative stress and improving plaque instability. Herein, we review the beneficial roles of DPP4 inhibitors in atherosclerosis as detailed. [ABSTRACT FROM AUTHOR]

• The stress field of the subduction zone near the Ogasawara Plateau is heterogeneous. • Based on the seismic pattern, the subduction system can be divided into three parts. • Three segments of the subducting Pacific plate are separated by 26.5°N and 24°N. • The segmentation of the subducting Pacific plate is related to the plateau subduction. The Ogasawara Plateau has a major control on the geology of the region between the Izu-Bonin and Mariana subduction zones. This region is important for understanding active collisional zones. We attempt to illustrate the stress field in the Wadati-Benioff zone of this region through seismic estimations. 49 events (M ≥ 3.5) are chosen for waveform inversion by the ISOLA software to distinguish the stress field. According to available focal mechanism solutions, the heterogeneous stress field parameters are determined for several depth ranges. Based on the epicentral distribution and seismic stress field, the subduction system at the west of the Ogasawara Plateau can be divided into three segments separated by 26.5°N and 24°N. At depths of 0–50 km in the outer-trench slope, the slab is characterized by a varying stress filed. The best-fit stress model with horizontal σ 3 and vertical σ 1 is related to the plate bending and preexisting faults. For the central segment, the solutions present a compressional stress regime in the outer-trench slope without preexisting faults, induced by the resistance of the buoyant plateau. The solutions for the depth range of 0–50 km in the forearc region, σ 1 coincides with the plate convergence and σ 3 dips steeply to the west in the northern and central segments, controlled by the friction effect and convergence of the plates. However, this depth range in the southern segment shows an extensional stress range, associated with subduction of older slab segment, relatively low rate of plate convergence and the morphological adjustment of the slab between different segments. At depths of 50–200 km, the inhomogeneous stress field exhibits a complicated extensional stress system with strike-slip focal mechanisms. At depths of 200–400 km, the seismicity presents a pronounced seismic gap and the stress field cannot be determined. The seismic gap may be attributed to the missing or tear of the subducting slab, which is caused by the subduction of the buoyant Ogasawara Plateau. The mechanism solutions are characterized by an inhomogeneous strain regime below 400 km, driven by gravity and strong contortion of the slab and resistance to penetration of the 660-km discontinuity. In contrast, there are little earthquakes below 400 km in the southern region of the Ogasawara Plateau. [ABSTRACT FROM AUTHOR]

Aims The clinical use of doxorubicin (Dox) is limited due to a degenerative irreversible cardiac toxicity, but the precise mechanisms that contribute to this pathological response are not understood. C1q/TNF-related protein 1 (CTRP1), which is a conserved protein of the C1q family, has notable metabolic and cardiovascular functions. However, whether CTRP1 can attenuate Dox-induced cardiac injury remains unclear. Our study aimed to investigate the effect of CTRP1 on Dox-induced cardiotoxicity and assessed the mechanisms of this effect. Materials and methods We manipulated CTRP1 expression in the heart using in vivo gene delivery system. Two weeks after gene delivery, the mice received a single intraperitoneal injection of Dox (20 mg/kg) to induce cardiac injury. Key findings Cardiac CTRP1 protein levels were decreased in DOX-treated mice. CTRP1 overexpression reduced plasma cardiac troponin I, restored cardiac function and attenuated cardiomyocyte apoptosis in Dox-treated mice. CTRP1 also improved cell viability and reduced lactate dehydrogenase release in vitro. Dox resulted in the decreased the protein kinase B (PKB/AKT) phosphorylation, which were restored by CTRP1 overexpression. AKT inhibition offset the inhibitory effects of CTRP1 on myocyte apoptosis in vitro. CTRP1 lost its protection against Dox-induced cardiac injury in mice with AKT deficiency. Furthermore, infusion of recombinant CTRP1 protein could reverse pre-established injury in heart induced by Dox treatment. Significance In conclusion, CTRP1 protected against Dox-induced cardiotoxicity via activation of AKT. CTRP1 has the therapeutic potential to treat Dox-induced cardiotoxicity. [ABSTRACT FROM AUTHOR]

The geological processes in the northernmost Philippine Sea plate, which is bounded by the Suruga and Sagami troughs, are a typical example of an active collision zone. We attempt to illustrate the stress field through seismic estimations and geodetic analysis and propose the kinematic mode of the northernmost tip of the Philippine Sea plate. Seven events (M ≥ 4.0) are chosen for waveform inversion by the ISOLA software to distinguish the stress field. In particular, six of the chosen events, which exhibit strike-slip motion, are distributed in the eastern area, where few focal mechanisms have been reported by previous studies. According to the available focal mechanisms, strike-slip faults with similar P and T axes are widely distributed in the study area. The stress inversion suggests that the northern area is characterized by a NW-SE compression and a NE-SW extension stress regime, although some spatial differences exist. As indicated by an analysis of the geodesy, epicenters, focal mechanisms, gravity anomalies and velocity structure, the deformation in the northernmost tip is mainly accommodated by several conjugate strike-slip fault systems with steep dips that center on the Izu volcanic line. Generally, the maximum principal stress of the kinematics is derived from the collision between the Philippine Sea plate and Central Japan. Because of the different subduction angles, rates and directions of the down-going plate, diverging slab-pull forces along the Suruga and Sagami troughs may be causing the NE-NNE extension in most of the areas that are bounded by the two troughs. The extension propagates southwards along the Izu volcanic line and reaches the area adjacent to Miyake-jima. [ABSTRACT FROM AUTHOR]

The purpose of the study is to summarize the application rule of multi-frequency sine wave compound magneto-optical modulation in measuring roll angle. Firstly, we establish the model of compound modulation signal composed of fundamental and multi-frequency sine wave signals, and then the modulated signal is analyzed with Bessel function. Secondly, we analyze the characteristic of AC signal extracted from the modulated signal, and discuss the feasibility of establishing angle measurement model with extremum in AC signal. Finally, we draw the conclusion that study on the fundamental sine wave signal superimposed on itself compound modulation in roll angle measurement is enough, the others is unnecessary. The study result has an important guiding significance on the application of multi-frequency sine wave compound magneto-optical modulation in measuring roll angle. [ABSTRACT FROM AUTHOR]