We proposed a modified Pn velocity and anisotropy tomography method by considering the Moho depth variations using the Crust 1.0 model and obtained high‐resolution images of the uppermost mantle Pn velocity and anisotropy structure from eastern Europe to western China. The tomography results indicate that the average Pn velocities are approximately 8.0 and 8.1 km/s under the western and eastern parts of the study area, respectively, with maximum velocity perturbations of 3%–4%. We observed high Pn velocities under the Adriatic Sea, Black Sea, Caspian Sea, Arabian Plate, Indian Plate, and in the Tarim and Sichuan Basins but low Pn velocities under the Apennine Peninsula, Dead Sea fault zone, Anatolia, Caucasus, Iranian Plateau, Hindu Kush, and in the Yunnan and Myanmar regions. Generally, regions with stable structures and low lithospheric temperatures exhibit high Pn velocities. Low Pn velocities provide evidence for the upwelling of hot material, which is associated with plate subduction and continental collision processes. Our Pn velocity and anisotropy imaging results indicate that the Adriatic microplate dives to the east and west, the hot material upwelling caused by subduction beneath the Tibetan Plateau is not as significant as that in the Caucasus and Myanmar regions, the lithosphere exhibits coupled rotational movement around the Eastern Himalayan syntaxes, and the areas to the north and south of 26°N in the Yunnan region are affected by different geodynamic processes. Our newly captured images of the uppermost mantle velocity and anisotropy structure provide further information about continental collision processes and associated dynamic mechanisms.

We used a newly developed Pn tomography method to obtain high-resolution uppermost mantle velocity and anisotropy structures beneath the Northwest Pacific region. The observed Pn velocities are consistent with the local tectonic background, where high Pn velocities are observed beneath the Japan Trench area and Songliao Basin, and low Pn velocities beneath the Kuril Islands, Japan Archipelago-Izu Islands, Kyushu Island, Changbaishan-Jingpohu volcanoes, Korea Peninsula, and Japan Basin. The new Pn velocity image outlines the subducting slabs along the trenches and the young seafloor within the Japan Basin. Our results also support the existence of hot upwelling feeding the Changbaishan, Jingpohu, and Chuga-Ryong volcanoes, where small-scale mantle convection may exist below the Northeast China region. Further east, both trench-parallel anisotropy below arcs and trench-perpendicular anisotropy within the back-arc region suggest subduction-dominant mantle flow, where anisotropy may be attributable to the lattice-preferred orientation of olivine induced by flow-related strain. The highly accurate uppermost mantle velocity and anisotropy structures provide crucial information outlining the complex dynamic processes near convergent plate boundaries.

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Gut microbiota ( GM ) is a collection of bacteria, fungi, archaea, viruses and protozoa , etc. They inhabit human intestines and play an essential role in human health and disease. Close information exchange between the intestinal microbes and the host performs a vital role in digestion, immune defence, nervous system regulation, especially metabolism, maintaining a delicate balance between itself and the human host. Studies have shown that the composition of GM and its metabolites are firmly related to the occurrence of various diseases. More and more researchers have demonstrated that the intestinal microbiota is a virtual ‘organ’ with endocrine function and the bioactive metabolites produced by it can affect the physiological role of the host. With deepening researches in recent years, clinical data indicated that the GM has a significant effect on the occurrence and development of cardiovascular diseases ( CVD ). This article systematically elaborated the relationship between metabolites of GM and its effects, the relationship between intestinal dysbacteriosis and cardiovascular risk factors, coronary heart disease, myocardial infarction, heart failure and hypertension and the possible pathogenic mechanisms. Regulating the GM is supposed to be a potential new therapeutic target for CVD .

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Speech enhancement is challenging because of the diversity of background noise types. Most of the existing methods are focused on modelling the speech rather than the noise. In this paper, we propose a novel idea to model speech and noise simultaneously in a two-branch convolutional neural network, namely SN-Net. In SN-Net, the two branches predict speech and noise, respectively. Instead of information fusion only at the final output layer, interaction modules are introduced at several intermediate feature domains between the two branches to benefit each other. Such an interaction can leverage features learned from one branch to counteract the undesired part and restore the missing component of the other and thus enhance their discrimination capabilities. We also design a feature extraction module, namely residual-convolution-and-attention (RA), to capture the correlations along temporal and frequency dimensions for both the speech and the noises. Evaluations on public datasets show that the interaction module plays a key role in simultaneous modeling and the SN-Net outperforms the state-of-the-art by a large margin on various evaluation metrics. The proposed SN-Net also shows superior performance for speaker separation.

The Aleutian-Alaska subduction zone lies at the junction of the Pacific and North American plates. The Pacific Plate subducted at the Aleutian trench (Figure 1) with the dip angle of the slab shifts from shallow subduction in the east to steep in the west (Eberhart-Phillips et al., 2006;Qi et al., 2007;Zhao et al., 1995). In addition, the variation of seismicity density and depth distribution, geochronology, geochemistry and metamorphism between the east and west indicates that the subducting plate is highly segmented (