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This article analyzes the recorded characteristics and differences of multiple heavy ground leveling machine construction and small magnitude natural earthquake events from November 2022 to May 2023 in Zhaotong Xunlong. Analysis shows that the initial motion of P-wave of the Zhaotong Xunlong strong rammed soil event is downward, with short duration, fast attenuation, and the maximum amplitude of P-wave and S-wave is smaller than that of natural earthquakes. The spectral characteristics recorded by the waveform of strong rammed soil event are significantly different from those of natural earthquakes, and the seismic phase P-wave and S-wave of the natural earthquake is obvious, while the seismic phase of the strong rammed soil event is not obvious. Utilizing Pg/Sg spectral ratio and cross Pg/Sg spectral ratio achieves classification and recognition of non natural earthquakes and natural earthquake events in dynamically compacted soil. The classification results indicate that when the frequency is greater than 5 Hz, the Pg/Sg spectral ratio criterion basically achieves the classification of natural earthquakes and strongly compacted soil events; The classification recognition accuracy corresponding to the cross Pg/Sg spectral ratio criterion is 91.3% for natural earthquake events and 90.7% for strong compacted soil events. The cross Pg/Sg spectral ratio criterion reflects the characteristic differences between natural earthquakes and strongly compacted soil events better than the single frequency band spectral ratio criterion.

Based on the quality evaluation results of the national seismic stations from 2018 to 2021 at Zhaotong Xunlong seismic sation, the improvement data analysis is given by analyzing the deduction of points and the reasons for the problems over the years. Combined with the actual situation of the station, corresponding experience and technical countermeasures such as level and strengthening system operation ability are presented. In order to improve the quality of seismic observations at the Zhaotong Xunlong seismic station in the future, it provides a principle to follow and significance guide for the improvement of the quality of the seismic observation data for this station and its brother stations.

Dendrobium officinale is a valuable homologous resource of medicine and food in China, which has rich health value. Dendrobium officinale polysaccharide is one of the important active ingredients in Dendrobium officinale. Therefore, research on development of the extraction, separation and purification, composition of monosaccharides, molecular weight of Dendrobium officinale polysaccharides are summarized in this review, and the effect of lowering blood sugar and improving diabetic complications, protecting of gastric mucosal injury, anti-tumor, regulating microecology are also discussed. In view of the current situation of polysaccharide content affected by many factors, poor repeatability of separation and purification, unclear structure analysis, and less in-depth structure-activity relationship of Dendrobium officinale, the future research views of Dendrobium officinale polysaccharides are put forward in order to provide useful reference for the development and utilization of Dendrobium officinale.

This paper uses the precursor observation data of the YRY-4 borehole strain gauge at Zhaotong seismic station to extract the interference events of rainfall on the observation data of the instrument. The results show that when the total rainfall reaches 40 mm and the instantaneous maximum rainfall is greater than 0.4 mm, the observation data of the YRY-4 borehole strain gauge is obviously disturbed by the rainfall; when the total rainfall is greater than 40 mm, the total rainfall and the observation data is a linear relationship between the strain variables. There is no significant corresponding relationship between the instantaneous maximum rainfall and the total rainfall. The analysis shows that the influence of rainfall interference mainly comes from rainfall infiltration and the load capacity of the geological water body around the station. Quantitative analysis of rainfall disturbance is helpful to distinguish the difference between anomalies and disturbances, and to accumulate experience so as to facilitate anomaly determination timely and effectively and serve earthquake research.

Taking cylindrical spur gear as study object，a nonlinear dynamics model of planetary gear transmission system is established by using mass concentration method. Four influences factors，namely backlash，time-varying meshing stiffness，meshing damping and comprehensive meshing error，are considered in the model，the dynamics equations corresponding to the model are listed and solved by the fourth-order Runge Kutta method. By changing the size of the backlash，the response states of the system under different backlash sizes are obtained. Finally，the time displacement image of relative position error，phase plane diagram and FFT spectrum are used to reflect the effect of specific backlash size on gear vibration response.

Objective To evaluate the relation between metabolic syndrome (MetS) and gastric cancer (GC) based on a meta-analysis. Methods The case-control studies about the relation between MetS and GC were retrieved from CNKI, WanFang Data, VIP, CBM, Web of Science, The Cochrane Library and PubMed database. The retrieval time was from inception to June, 2020. Two researchers independently screened the literatures, extracted the data and evaluated the quality of the included studies. The meta-analysis of the included literatures was conducted by the Stata 12.0 software. Results A total of six literatures, involving 43617 participants, were included. The results of meta-analysis showed that there was no statistically significant difference between GC and non-GC groups in the risk of hyperglycemia (OR=1.24, 95%CI: 0.59-2.61), hypertension (OR=1.40, 95%CI: 0.60-3.25) or MetS (OR=0.79, 95%CI: 0.44-1.39), respectively. Conclusion MetS may not be related to the risk of GC.

There are many problems in safety management and risk assessment of underground reservoir project in karst area because of the special structure and environment.Taking a typical karst underground reservoir project in southwest China as the research object,this paper establishes the three-dimensional finite element model of its cave block to analyze the variation law of its temperature field,stress field and displacement field under different working conditions.The results show that:the overall deformation of the cave block was small,and the stress level of the cave block was generally within the safe range under various working conditions.There was stress concentration at the local position between the cave block and bedrock,but the overall stress distribution met the requirements of the code.The research results serve as a reference for safety evaluation and risk analysis of underground reservoir projects in karst areas.

Objective To detect the serum levels of IL-25 and IL-17 in rheumatoid arthritis (RA) patients and investigate the potential relationship with bone erosion and concomitant interstitial lung disease (ILD). Methods The study enrolled a total of 117 RA patients and 56 healthy subjects as controls. The serum levels of IL-25 and IL-17 were determined by ELISA, and rheumatoid factor (RF) was detected by turbidimetric immunoassay, anticyclic citrullinated peptide (anti-CCP) antibody as well as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were also tested. ILD was identified on high-resolution computed tomography (HR-CT), the degree of bone erosion was inspected by musculoskeletal ultrasonography, and radiographic grade was graded by Sharp-van der Heijde Score (SHS). Disease activity in RA was scored with the DAS28 and visual analogue scale (VAS). Correlation analysis was used to evaluate the correlations of IL-25 and IL-17 in different groups. Results Compared with healthy control group, the serum levels of IL-25 and IL-17 increased significantly in the patients with RA. Compared with bone erosion negative group, the serum level of IL-25 was higher significantly in bone erosion group. The level of IL-25 was higher in the ILD group of RA patients than the non-ILD group. In addition, there were positive correlations between the serum level of IL-25 and RF-IgG (r=0.285), RF-IgA (r=0.314), RF-IgM (r=0.380). Meanwhile, the serum level of IL-17 had the positive correlations with RF-IgG (r=0.198) and RF-IgM (r=0.273). Both of them had no correlations with anti-CCP antibody. Conclusion The serum level of IL-25 is raised in RA patients with bone erosion and ILD.

Objective: To investigate the expression of full-length spleen tyrosine kinase [SYK (L)] mRNA and protein in human oral squamous cell carcinoma (OSCC) as well as its possible effects on the invasion and metastasis of OSCC., Methods: The expression of SYK (L) was detected in 27 cases of OSCC tissues and its matched adjacent non-cancerous tissues by real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, and immunohistochemistry. Fourteen cases of normal oral gingival tissues were also analyzed as a normal control., Results: Reduced mRNA and protein expression of SYK (L) in OSCC tissues was observed compared with that in normal oral gingival tissues (P<0.01) and adjacent non-cancerous tissues (P<0.05). SYK(L) expression was significantly associated with lymph-node metastasis (P<0.05)., Conclusion: SYK(L) is a candidate tumor suppressor for OSCC tissues, and has an inhibitive effect on the initiation, proliferation, and lymph-node metastasis of human OSCC.

Objective: To investigate the effects of burn trauma on pituitary-testis axis., Methods: The changes in serum estradiol(E2), testosterone(T), luteinizing hormone(LH), and follicle stimulating hormone(FSH) levels were dynamically investigated by RIA in 30 days after thermal injury in 28 burnt men., Results: The serum FSH, LH, and T levels significantly decreased after injury, and there was some increase from PBD(postburn day) 14 to 30. In patients in group II and III (BSA > 30% TBSA), not all of their FSH, LH, and T levels reached the normal control on the PBD 30. Serum E2 levels were elevated after injury, then returned gradually to normal. In three patients who died, their mean T levels were significantly lower than patients who survived, but mean E2 levels were significantly higher than that of survivors., Conclusion: The activity of pituitary might be depressed after burn trauma. The imbalance between E2 and T might play a role in the processes of immuno-depression after injury. The changed extent of E2 and T levels was correlated to burn size. They could be sensitive indicators of burn stress.