The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly characterized by low velocity of P wave, can be divided into three parts in terms of depth. At the depth range of 9~15 km, the distribution of the magma system is characterized by extensiveness, large scale and near-SN orientation. This layer is the major place for magma storage. From the depth of 15 km down to the lower crust, it is characterized by small lateral scale, which indicates the "trace" of magma intrusion from the upper mantle into the crust and also implies that the magma system most probably extends to the upper mantle, or even deeper.(less than 8-9 km deep), the range of magma distribution is even smaller, centering on an SN-oriented area just north of the Tianchi crater. If low velocity of P wave is related to the magma system, it then reflects that the magma here is still in a state of relatively high temperature. In this sense, the magma system of Changbaishan-Tianchi volcanic region is at least not "remains", in other words, it is in an "active" state.

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To identify the clinical risk factors and investigate the efficacy of a classification model based on the identified factors for predicting 2-year recurrence after ischemic stroke. From June 2017 to January 2019, 358 patients with first-ever ischemic stroke were enrolled and followed up in Shenzhen Traditional Chinese Medicine Hospital. Demographic and clinical characteristics were recorded by trained medical staff. The outcome was defined as recurrence within 2 years. A multivariate logistic regression model with risk factors and their interaction effects was established and evaluated. The mean (standard deviation) age of the participants was 61.6 (12.1) years, and 101 (28.2%) of the 358 patients were female. The common comorbidities included hypertension (286 patients, 79.9%), diabetes (148 patients, 41.3%), and hyperlipidemia (149 patients, 41.6%). The 2-year recurrence rate was 30.7%. Of the 23 potential risk factors, 10 were significantly different between recurrent and non-recurrent subjects in the univariate analysis. A multivariate logistic regression model was developed based on 10 risk factors. The significant variables include diabetes mellitus, smoking status, peripheral artery disease, hypercoagulable state, depression, 24 h minimum systolic blood pressure, 24 h maximum diastolic blood pressure, age, family history of stroke, NIHSS score status. The area under the receiver operating characteristic curve (ROC) was 0.78 (95% confidence interval: 0.726–0.829) with a sensitivity of 0.61 and a specificity of 0.81, indicating a potential predictive ability. Ten risk factors were identified, and an effective classification model was built. This may aid clinicians in identifying high-risk patients who would benefit most from intensive follow-up and aggressive risk factor reduction. The clinical trial registration number: ChiCTR1800019647

Postpartum depressive disorder (PPD) is a unique subtype of major depressive disorder and a substantial contributor to maternal morbidity and mortality. However, the pathogenesis of PPD has still remained elusive, and it may associate with genetic and environmental factors. Gut microbiota has already been proved to be associated with depression; however, a limited number of studies have concentrated on PPD. The present study aimed to explore the potential correlations between gut microbiota and PPD. In this study, 57 participants were enrolled, in which fecal samples of 28 patients with PPD and 16 healthy controls (HCs) were collected and then analyzed by high-throughput sequencing of the 16S ribosomal RNA (rRNA) gene. The results showed that diversity and composition of gut microbial communities were partly different between PPD patients and HCs. The relative abundance of Firmicutes phyla was lower in PPD patients. The levels of several predominant genera were significantly different between PPD patients and HCs. More importantly, the PPD patients experienced reduced levels of Faecalibacterium, Phascolarctobacterium, Butyricicoccus , and Lachnospiraceae , as well as increased levels of Enterobacteriaceae family. In addition, a correlation was observed between levels of Phascolarctobacterium, Lachnospiraceae, Faecalibacterium , and Tyzzerella.3 and the severity of depressive symptoms. Various kinds of bacteria, such as Lachnospiraceae and Faecalibacterium , were found to be associated with levels of sex hormones. This study indicated the correlation between gut microbiota and PPD, and gut microbiota-based biomarkers may be helpful for the diagnosis and treatment of PPD patients. However, further studies need to be conducted to clarify the cause–effect relationship between PPD patients and gut microbiota and to highlight the suitability of gut microbiome as a biomarker.

Using 2‐D ray tracing software package, the crustal and upper‐mantle velocity structure and deep features of the Changbaishan Tianchi volcanic region and its vicinity are studied through travel‐time fitting and synthetic seismogram computation with deep seismic sounding (DSS) data acquired along the Changbai‐Dunhua profile. The results show that the crust of this region is separated into the upper crust and the lower crust by the interface C2. The upper crust is 19–23km thick and P‐wave velocity is 6.00–6.25 km/s. The lower crust is 12–17km thick, which is composed of a homogeneous velocity layer and a crust‐mantle transition layer 6–9km thick. Crustal thickness is 31–33km in Dunhua and becomes gradually greater southeastwards to its maximum value of 39km in the Tianchi volcanic region. In the Tianchi volcanic region, there exists a low‐velocity body in the crust, whose velocity is about 0.15 km/s lower than that of the adjacent medium. Results of seismic profiling, seismic tomography, and magnetotelluric sounding suggest that in Tianchi volcanic region there is a low‐velocity, low‐density, and low‐resistivity anomalous body, which may indicate the existence of a magma chamber in the crust.