Search

Purposes Origin software was adopted to study the mechanism and final effects of rainwater erosion prevention of Earthen Sites with bare soil and herbs in Western Wall of Jinyang Ancient City. Methods The data analysis method of field artificial simulation rainfall experiment through the software of Origin was used to compare the effects of the underlying surface layer on the runoff and sediment producing processes on the slope surface at different times. Findings Pre-runoff interception Q0 of Fresh Herbs was negatively correlated with runoff starting time T0. And Q0 was in descending order of Dry Herbs, Fresh Herbs, and Bare Soil. Sediment producing coefficient Csy and sediment producing intensity Isy of Fresh Herbs were positively correlated with rainfall intensity Irf. Runoff coefficients Cro and Csy were in descending order of Bare Soil, Dry Herbs, and Fresh Herbs. By forming a mud surface, exposed earthen sites were less affected by rainwater infiltration, making them suitable for arid climate zones. By strengthening anti-erosion, herbal earthen sites reduced soil surface erosion, making them suitable for semi-arid and semi-humid climate areas. Conclusions Origin analysis confirms that herbal plants have a significant effect on improving the anti-erosion of earthen sites. The phenomenon of herbs covering is beneficial to the protection of local earthen sites in Shanxi. However, when extreme sustained heavy rainfall occurs between September and October, further research is needed to determine whether herbal plants are suitable or not for covering earthen sites.

In order to explore the economic and carbon reduction benefits of photovoltaic-storage-charging integrated stations and achieve reasonable configuration of internal components, a multi-objective optimization configuration method for stations that takes into account economic and low-carbon aspects is proposed. Firstly, based on the functions and requirements of each module in the charging station, the sources of carbon emissions generated by station is explored, and a mathematical model for the cost and carbon emissions of each module in the station is established. Then, with the goal of minimizing the annual investment and operating cost of the system and carbon emissions, a multi-objective particle swarm optimization algorithm based on three-black-hole capturing strategy is used to optimize the configuration of various modules of stations in different load scenarios, and the optimal configuration plan for each component module of the station under three scenarios is obtained. The comparative results show that the method proposed in this article can effectively reduce the cost and carbon emissions during planning and operation, and improve the economic and environmental benefits of stations. Finally, the technique for order preference by similarity to ideal solution is used to provide a compromise optimization plan for the optimal scenario, which can provide reference for the current investment and construction of photovoltaic-storage-charging integrated stations.

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.