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Objective Based on the virtual simulation fatigue test technology, fatigue life analysis and reliability evaluation of the bogie arm positioning node of a certain type of vehicle are carried out to improve the vehicle stability and guarantee the train operation safety. Method ABAQUS software is used to establish a finite element model of the arm positioning node and obtain the stress and strain data. FE-SAFE software is used to set the fatigue parameters of rubber material, simulate and analyze its fatigue life. Graph test method is used to test the distribution hypothesis of pseudo-failure fatigue life and to select the optimal life distribution. The relation between the life distribution parameters and the stress level is used to fit a proper functional relation and evaluate the reliability of the arm positioning node fatigue life under normal stress level. Result & Conclusion Under normal stress level, only the rubber bushing in arm positioning node will have fatigue damage. The bottom end of the rubber bushing is the area with the lowest pseudo-failure fatigue life value, and is also the area where the damage occurs first. On-site test and fatigue simulation results verify the accuracy of the finite element model of arm positioning node. The optimal normal life distribution is determined. Under normal stress level, the number of fatigue life cycles is about 210,000 when the reliability of the arm positioning node is 0.9.

Objective Based on the measured data of the train wheelsets on Shanghai Metro Line 17, the wheelset wear pattern is studied, and a wear model of wheel rim thickness and wheel diameter is established to improve the safety and maintenance efficiency of urban rail transit vehicles. Method The measured wheelset data are pre-processed to eliminate data errors. Curve fitting and error analysis method are used to establish the wear model of wheel rim thickness and wheel diameter. The fitting standard deviation of wear rate and that of the error value between the true value and the error fitting curve are used as evaluation indexes to evaluate the accuracy of the wear model. The wheelset wear model is verified with Train 1701 and Train 1721 respectively. Result & Conclusion Both the fitting standard deviation of 4th power fitting curve of wear rate for Train 1701 and Train 1721 wheelset rim thickness and wheel diameter, and that of 6th power fitting curve of the error value between the true value and the error fitting curve are close to zero, verifying that the vehicle wheelset wear model can accurately predict the wheelset wear of different types of trains and different vehicle positions of the same train on Shanghai Metro Line 17.

Objective To investigate the status of readiness and quality for hospital discharge and its influencing factors in patients undergoing radiofrequency ablation for atrial fibrillation. Methods A total of 151 patients undergoing radiofrequency ablation for atrial fibrillation were collected using convenience sampling method. General data questionnaire, Readiness for Hospital Discharge Scale(RHDS) and Quality of Discharge Teaching Scale (QDTS were used to conduct a questionnaire survey on the subjects. Results The total score of RHDS was(104. 43±15. 57), indicating a high level of readiness for hospital discharge. The total score of QDTS was (159. 56±17. 36), indicating a moderate-to-high level of quality assessment on hospital discharge. The quality of discharge is positively associated with readiness for hospital discharge(r＝0. 777, P＜0. 05). Age, marital status, occupational status, family income, disease occurrence, number of hospitalizations, regular hospital revisit, reduced ability of daily living, Comorbidity of other diseases and type of drug administration. Conclusion Findings of the study showed a high level of readiness and quality for hospital discharge in patients undergoing radiofrequency ablation for atrial fibrillation. Patients’ awareness of readiness for hospital discharge is correlated with quality for hospital discharge. Medical workers should take effective intervention to improve quality of hospital discharge teaching and quality of life after hospital discharge (目的 探讨心房颤动患者射频消融术后出院准备度及出院指导的现状及其相关影响因素。方法 随机抽取2022年1月—8月在医院接受房颤射频消融术治疗的患者151例作为研究对象。采用一般资料调查问卷、出院准备度量表(RHDS)和出院指导量表(QDTS)对151例研究对象进行调查。结果 患者RHDS量表总分为(104. 43±15. 57)分, 处于较高的水平; QDTS量表得分(159. 56±17. 36)分, 处于中等水平。出院指导质量与出院准备度呈正相关(r＝0. 777, P＜0. 05)。年龄、婚姻状况、工作状态、家庭人均收入、发病情况, 疾病住院次数、定期多次复诊、生活自理能力下降、合并其他疾病与服用药物种类是影响患者出院准备度的因素。结论 心房颤动患者射频消融术后出院准备度和出院指导质量处于较高水平, 且心房颤动患者对出院准备度的感知与其获得的出院指导质量关系密切。医务人员要找寻切实可行的措施提高指导质量, 对出院指导进行有效的干预, 从而可改善患者出院后的生活质量, 进而提高患者的出院准备水平。)

Pheochromocytoma is one of rare tumors of neuroendocrine. Most of the tumors are sporadic with about 1/3 of them caused by genetic mutations. Papillary thyroid carcinoma (PTC) from thyroid follicular cells is the most common malignant tumors. However, pheochromocytoma with PTC is rarely reported. Here we present a case report of an 41-year-old male patient found to have an adrenal pheochromocytoma combined with PTC, and PTC was diagnosed first with fine needle aspiration. The patient admitted to hospital, and surgery would be prepared when abnormal blood pressure rose, and operation was suspended. Further CT scan and blood biochemical examination were performed, and concurrent adrenal pheochromocytoma was considered. Multidisciplinary team decided to perform adrenal surgery priority. When the recovery of patient appeared after first operation, radical thyroidectomy was performed. Whether the co-existence of pheochromocytoma and PTC is coincidence or caused by RET gene or unknown inherited genetic mutations is unclear, so accumulation of studies with more combined cases should be done and genetic testing data are needed.

In order to improve the utilization of Haliotis discus hannai mantle, collagen purified from it was hydrolyzed by trypsin and pepsin to prepare angiotensin I-converting enzyme (ACE) inhibitory peptides. The hydrolysate was purified by sequential ultrafiltration, SuperdexTM peptide 10/300 GL gel filtration chromatography and high performance liquid chromatography (HPLC). Three ACE inhibitory peptides, SGEVGQ, QRGPAGAQGPQ and GPPGPAGAR, were obtained . Among them, GPPGPAGAR had the highest ACE inhibitory activity with a half maximal inhibitory concentration (IC50) of 177.1 μmol/L. Molecular docking results showed that GPPGPAGAR mainly acted on the S1 active pocket of ACE and the inhibitory mode was similar to that of lisinopril. GPPGPAGAR still showed high ACE inhibitory activity after simulated gastrointestinal digestion. This study will provide a reference for deep processing of abalone mantle and the development of ACE inhibitory peptides.

[Objective] Understandings of the ecological evolution in the Hunshandake Sandy Land are divergent duo to the differences in study area, data used, and period of study. How the vegetation in the hinterland and marginal ecotones of the Hunshandake Sandy Land interacts with regional climate and responds to human activities remain to be addressed. [Methods] In this study, the Gobi desert area was set as the background area (CK), and the Hunshandake Sandy Land and its surrounding areas were divided into a core area (CA) and four ecotones. Based on the long-term GIMMS NDVI3g v1 (1982-2015) dataset, combined with climate data (annual temperature and precipitation) from 1982 to 2015, nighttime light dataset (1984-2015), and population and herbivore data of each banner/county (1986-2015), the correlations between NDVI and climate change and human activities in the CK, CA and the ecotones were analyzed. [Results] The results show that: (1) Vegetation phenology was regionally heterogeneous. The length of growing season (LOS) was between 158 and 196 days, and the phenological difference within the region reached 38 days. (2) The change rate of NDVI was spatially different. Total NDVI increased at a rate of 0.00021/10a, while the rate of change in each region varied, with a maximum difference of 17 folds. (3) The response of vegetation to climate variability was zonal. In these ecotones, NDVI change was more sensitive to monthly temperature than to monthly precipitation. (4) The coefficient of variation (Cov) of vegetation went through several stages. The Cov fluctuated little in the 1980s, was relatively stable in the 1990s, and had higher positive variation in the first 15 years of this century. (5) The response of vegetation cover to human activities was not significant. While NDVI was not correlated with population density and nighttime light intensity per square kilometer, it was locally positively correlated with sheep and total herbivorous livestock density per square kilometer. [Conclusion] These results suggest that the NDVI of the Hunshandake Sandy Land and its ecotones fluctuated in response to climate change, and although it has improved in this century, it has only reached the level of the mid- to late 1980s.

Non-alcoholic fatty liver disease (NAFLD) is a chronic non-communicable disease. It is a metabolic syndrome (MS) in the liver. Menopause is a physiological phenomenon of women due to the decline of ovarian function, which is characterized by the deterioration of hypothalamic-pituitary function. Clinical and epidemiological studies have shown that the incidence trend of NAFLD has gender differences and is related to metabolic parameters such as glucose, lipids, and blood uric acid. The incidence of NAFLD in premenopausal women is lower than that in males, while the incidence of NAFLD in postmenopausal women gradually increases to the same as that in males. The mechanism may be mainly related to the changes of sex hormones in postmenopausal women (mainly the decrease of estrogen). The changes of sex hormones such as the decreased levels of estrogen and sex hormone binding globulin (SHBG) and the relatively increased level of androgen can increase the incidence of MS components such as abdominal obesity, abnormal blood lipid metabolism and insulin resistance (IR), making menopause an important independent risk factor for NAFLD in women. Estrogen, androgen receptor antagonists and phytoestrogens can improve hepatic steatosis and IR through many ways, reduce the severity of NAFLD and delay its progression to liver fibrosis, which have certain therapeutic significance for postmenopausal women with NAFLD, but also have some limitations. This paper reviews the research progress in the relationship between menopause and NAFLD in recent years, so as to provide ideas and reference for the prevention and treatment of NAFLD in postmenopausal women.

Objective To investigate the clinical effect of buccal fat pad flaps on the restoration of maxillary defects. Methods Nineteen cases with oral-nasal communications and maxillary soft and hard tissue defects ranging from 3.0 cm×2.0 cm-5.0 cm×4.0 cm after resection of the primary tumor foci were repaired with a pedicled buccal fat pad flap, and the maxillary sinus cavity and oral-nasal communication were closed. The survival, healing and complications of the flap were observed during the 3-month follow-up. Results The buccal fat pad flaps of 19 patients all survived. Five days after the operation, the buccal fat pad flap was dark red with slight edema, and the maxillary defect area collapsed. Ten days after the operation, most of the buccal fat pad flap turned pink, and the collapse was alleviated. One month after the operation, the buccal fat pad flap had no obvious collapse, and its surface was epithelialized, with a shape and color close to those of the normal mucosa. The opening was slightly limited. Three months after the operation, the buccal fat pad flap was completely epithelialized, with no difference from the surrounding tissue, and the opening was approximately 3 transverse fingers. No complications, such as swelling and necrosis of the buccal fat pad flap, limitation of mouth opening, maxillary sinus fistulas, oral-nasal communications and facial changes occurred in 19 patients within 3 months after the operation. Conclusion The application of a buccal fat pad flap has a good effect to repair maxillary tissue defects and close oral maxillary sinus communication with diameters less than 5 cm, so it can be widely used in the clinic.

The general aviation airplane is an important component part of civil airplanes,and its shape feature is of important influence on aircraft drag.The numerical simulation method based on Navier-Stokes equation is utilized to analyze the barrel shape feature of drag polar curve of classical general aviation airplane,and the influence of upper surface outline curvature of fuselage.The aerodynamic characteristics difference for a typical general aviation airplane under three different rear fuselage contractions are studied,including upper surface,lower and side ones.The aerodynamic characteristics of basic shape and improvement shape are compared.The results show that,with the increase of contraction rate,the pressure drag and frictional drag for lower surface and side surface are decreased,while for the upper surface,the pressure drag is increased.The suitable fuselage contraction can reduce the pressure drag of 29.76%,and increase the maximum lift-to-drag of the fuselage of 6.34%.The reasonable contraction pattern can not only increase the lift-drag ratio,but improve the longitudinal static stability as well.

Ceramic 3D printing based on stereolithography has attracted wide attention because it can fabricate complex ceramic components with high dimensional accuracy, good surface finish, uniform microstructure, and excellent mechanical properties. It is one of the important technical means to achieve high-performance parts by additive manufacturing. The core of the technology is to prepare ceramic slurries with high solid loading and good printability, and its composition has a vital influence on the curing effect and printing process. In this review, two main additive manufacturing methods, stereolithography (SL) and digital light processing (DLP), commonly used in ceramic 3D printing were introduced, and advantages and disadvantages of the two methods were compared. Based on the research work in the field of ceramic slurries in recent years, the effects of monomer/oligomer and diluent, dispersant, physical properties of ceramic particles and solid loading on viscosity, shear thinning/thickening behavior, viscoelasticity, yield stress were discussed. Finally, the main development trends and challenges of ceramic slurries via stereolithography were put forward in, and a general guiding principle for the construction of ceramic slurries with high solid loading was provided.

Objective To investigate the expression of AKAP12 in HER2-positive breast cancer and its relation with clinicopathological factors and clinical significance. Methods UALCAN database was used to explore AKAP12 mRNA expression in breast cancer and para-cancerous tissues. AKAP12 protein expression in 120 cases of breast cancer tissues, adjacent tissues and 8 cases of metastases tissues were detected by immunohistochemistry. Then we analyzed the relation between AKAP12 protein expression and clinicopathological factors. Bc-GenExMiner v4.4 database was used to explore the relation between AKAP12 mRNA expression and overall survival. The relation between AKAP12 protein expression and overall survival was analyzed by GraphPad Prism 7.0. Results AKAP12 expression in breast cancer tissues was lower than that in para-cancerous tissues (P < 0.05). AKAP12 protein expression in metastasis was lower than that in primary lesion (P < 0.05). AKAP12 was negatively related to tumor size and TNM stage (P < 0.05). Survival analysis showed that patients with low AKAP12 mRNA and protein expression had shorter overall survival than those with high AKAP12 expression (P < 0.05). Univariate and multivariate Cox regression analyses revealed that AKAP12 expression, vascular infiltration and radiotherapy were independent risk factors for the prognosis of HER2-positive breast cancer patients. Conclusion The low AKAP12 expression is related to the prognosis of HER2-positive breast cancer patients.

Most of existing comprehensive exploration technologies for water-hazard on coal mine working face adopt conventional rotary drilling method with lots of boreholes and heavy workload. In addition, blending deformation of drill pipes, geological condition variation in boreholes and alterations of drilling parameters during construction process would lead to borehole deflection, which may cause wrong decision about water-hazard exploration. For above problems, a comprehensive exploration technology based on directional drilling was proposed and applied to water-hazard detection on fully mechanized mining face of a coal mine. The application process is as follows: Firstly, mine audio-frequency electric penetration technology is used in the comprehensive exploration technology to detect anomalous area with low apparent resistivity on the working face, and then directional drilling technology is adopted to directly expose water-rich zone. It is determined that there is a water-conductive collapse column of Ordovician limestone karst in the anomalous area through observing water gushing in the boreholes and chemically examine quality of the water. Meanwhile, extension state and boundary of the water-conductive collapse column in the working face are delineated. Position of open-off cut is redesigned according to comprehensive exploration results, so as to effectively eliminate hidden water-inrush danger caused by exposing the water-conductive collapse column during mining process.

In this paper, the elemental analysis-stable isotope ratio mass spectrometer (EA-IRMS) is modified to testing different forms of sulfur isotope standard material and sample. A SO2 gas trap tube is installed after chromatographic column to trap the SO2 gas generated by redox reaction and the captured SO2 can be used as reference gas several times, there is no need to introduce high-purity SO2 gas externally, which reduces the damage to the instrument pipeline corrosion and laboratory environment. When the amount of barium sulfate is about 400 μg, SO2 gas in the trap tube can provide at least 20 peak center focus. Modified EA-IRMS system testing sulfur isotope standard material (IAEA-SO-5, IAEA-S-2, IAEA-S-3, EMA-P1), when the sulfur element injection volume is 20 μg, the δ34S value test accuracy achieve 0.2‰(n=3), 4 kinds of international standard material measured value and true value have a good correlation coefficient (R2=1), it indicates that the δ34S value of different compounds of sulfur can be mutual calibration, and the modified EA-IRMS can meet the accuracy requirement of the sulfur isotope test.

The prevalent pretreatment method for sulfur isotope determination in water samples is to convert dissolved SO2-4 into solid BaSO4. However, when this method is applied to sulfate samples with small volume and low-concentration (0～20 mg·L-1), there are some problems such as time-consuming and low recovery rate, which would cause uncertain effects on the results of sulfur isotope determination. In this paper, considering the effects of different conditions(Ba2+ addition, reaction temperature, pH, settling time) on recovery rate and determination of δ34S BaSO4, the method of converting dissolved SO2-4 into solid BaSO4 was optimized. In addition, the optimized method has been tested in four different types of water samples(rain water, lake water, sewage and seawater) . The results show: 1) The recovery rate of SO2-4 was controlled by the precipitation generating rate and reaction time. Under the condition of the the same reaction time, the precipitation generating rate was positively correlated with the super-saturation ratio and temperature, while negatively with the concentration of H+, and stirring can accelerate the formation of BaSO4 crystals. 2) The optimized pretreatment process is as follows: add appropriate amount of hydrochloric acid and barium chloride to the water sample（pH=2.6, super-saturation ratio≥55）, and stir with a glass rod at a constant speed for 1 minute, heat in a water bath at 90 ℃ for 1 hour, then cool to normal temperature and use filter membrane to collect solid BaSO4. 3) The optimized pretreatment method has been tested in natural samples, the test result shows that dissolved SO2-4can be completely converted into solid BaSO4 within 1 hour without any sulfur isotope fractionization. In rainwater samples with low SO2-4 concentration (3.24 mg·L-1), the conversion rate increased from 0 to 98.7%, and the δ34S value was determined to be about 15.7‰±0.1‰; in lake water samples with medium SO2-4 concentration (30.34 mg·L-1) , the conversion rate increased from 26% to 100%, and the δ34S value was determined to be 5.8‰±0.2‰. While, the recovery rate or δ34S value in sewage and seawater samples with high SO2-4 concentration (140.4～2 516.4 mg·L-1) are close to that got by prevalent method. In conclusion, the optimized pretreatment method effectively increases the recovery rate of low-concentration water-soluble sulfate samples and avoids sulfur isotope fractionization during the conversion process. Evidently, this optimized method is also applicable to samples with medium and high SO2-4concentrations.

Objective To explore the regulative effect of miR-214 on oxidative stress injury induced by hypoxia reoxygenation (H/R) in H9c2 myocardial cells though targeted inhibition of CaMKⅡ. Methods Rat myocardial H9c2 cells were randomly divided into 4 groups, ①control group: H9c2 cells without any treatment; ② H/R group: the myocardial cells were cultured in hypoxia for 24 h and then reoxygenation for 6 h; ③ mimics+H/R group: the myocardial cells were transfected with miR-214 and then cultured with H/R as above; ④ mimics negative control (MNC)+H/R group: the myocardial cells were transfected with miR-214's mimics negative control and then cultured with H/R as above. CCK-8 assay was used to detect the viability of cells. qPCR was adopted to detect the expression of miR-214. Flow cytometry, TUNEL assay, and SOD or MDA detect kits were used to determine the reactive oxygen species (ROS) levels and cell apoptosis. The association of miR-214 with CaMKⅡ was examined by double-luciferase reporter assay, and their changes at mRNA and protein levels were detected by qPCR and Western blotting. After H9c2 cells were transfected with recombinant adenovirus carrying CaMKⅡ gene or the control adenovirus, the regulative effect of miR-214 on oxidative stress of cells was examined by the above methods. Results CCK-8 assay showed that compared with normal group, the cell viability of H/R group was significantly decreased (P < 0.05), while miR-214 overexpression could obviously increase the cell viability (P < 0.05). qPCR results showed that the expression level of miR-214 was markedly downregulated in the H/R group than the control group, while notable increase of miR-214 was observed in the miR-214 mimics group (P < 0.05). Compared with the normal group, the ROS production, MDA level and TUNEL positive cells were obviously increased, while the SOD level was significantly decreased in H/R group (P < 0.05), but opposite trends were observed when the HR group compared to and the miR-214 mimics group (P < 0.05). TargetScan server indicated that there was binding site of miR-214 and CaMKⅡ. The dual luciferase reporter assay also confirmed that miR-214 could bind to CaMKⅡ in H9c2 cells. In addition, qPCR and Western blot results showed that H/R treatment increased the expression of CaMKⅡ at mRNA and protein levels, but miR-214 significantly inhibited the enhanced expression induced by H/R. Overexpression of CaMKⅡ in H9c2 cells resulted in partially blocked effects of miR-214 on oxidative stress and apoptosis induced by H/R treatment. Conclusion Overexpression of miR-214 can regulate oxidative stress and apoptosis of H9c2 cells by inhibiting CaMKⅡ at the transcription level.

Objective: To verify whether FN1 and ZNF438 are the androgen receptor(AR) target genes in LNCaP-AI cells and investigate the effects of AR exerts on FN1 and ZNF438 gene expression., Methods: ChIP-PCR and agarose gel electrophoresis were performed to verify the fact that AR acted on FN1 and ZNF438 gene. Subsequently, LNCaP-AI cells were treated with dihydrotestosterone(DHT)and lentivirus transfection to down-regulate AR expression. The expression of FN1 and ZNF438 gene in mRNA and protein levels were analyzed by RT-qPCR and Western blot., Results: FN1 and ZNF438 gene enrichment of AR-ChIP group were 7.274±0.290 and 6.843±0.078, significantly higher than the IgG-ChIP group of 1.004±0.113 and 1.000±0.014 (t(FN1)=34.91, t(ZNF438)=128.377, P<0.05). Differences were statistical significance. After DHT stimulation, the expression of FN1 and ZNF438 gene in mRNA and protein levels were 0.434±0.050 and 0.069±0.042, significantly lower than the control group of 1.000±0.016 and 1.025±0.277 (t(FN1)=18.532, t(ZNF438)=5.905, P<0.05). Differences were statistical significance. Moreover, after AR down-regulation, the expression of FN1 and ZNF438 gene in mRNA and protein levels were 17.579±4.415 and 1.895±0.424, significantly higher than the control group of 1.028±0.445 and 1.041±0.190 (t(FN1)=6.461, t(ZNF438)=3.184, P<0.05). Differences were statistical significance., Conclusions: FN1 and ZNF438 gene are AR negatively regulated target genes in LNCaP-AI cells. The study might provide a new sight to further explore the mechanism of LNCaP-AI cells grow in androgen-depleted conditions.

Objective: To explore the effects of glutamine, eicosapntemacnioc acid (EPA) and branched-chain amino acids supplements in esophageal cancer patients on concurrent chemoradiotherapy and gastric cancer patients on chemotherapy., Methods: From April 2013 to April 2014, a total of 104 esophageal and gastric carcinoma patients on chemotherapy or concurrent chemoradiotherapy were recruited and randomly divided into experimental and control groups. Both groups received dietary counseling and routine nutritional supports while only experimental group received supplements of glutamine (20 g/d), EPA (3.3 g/d) and branched-chain amino acids (8 g/d). And body compositions, blood indicators, incidence of complications and completion rates of therapy were compared between two groups., Results: After treatment, free fat mass and muscle weight increased significantly in experiment group while decreased in control group (P < 0.05). And albumin, red blood cell count, white blood cell count and blood platelet count remained stable in experiment group while declined significantly in control group. During treatment, compared to control group, the incidences of infection-associated complication were lower (6% vs 19%, P < 0.05) and the completion rates of therapy were significantly higher in experiment group (96% vs 83%, P < 0.05)., Conclusion: Supplements of glutamine, EPA and branched-chain amino acids can help maintain nutrition status, decrease the complications and improve compliance for esophageal cancer patients on concurrent chemo-radiotherapy and gastric cancer patients on postoperative adjuvant chemotherapy.