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The transmission tower and tower line coupling system is an important carrier of the power system transmission process. Strong winds in coastal areas have a significant impact on the transmission tower and tower line system. To study the dynamic response characteristics of tower line system under the action of random fluctuating wind fields, the 1W2C9 drum-type self-supporting transmission tower in Guangdong is taken as the research object. Finite element models for the single tower and one tower two-line tower line coupling system are established. By combining the Davenport wind speed spectrum with the fourth order autoregressive method, the fluctuating wind fieldswith spatial correlation are simulated for a single tower with 9 nodes and tower line system with 49 nodes. The dynamic response of a single tower and tower line system under this fluctuating wind field is studied, and the influence of different wind direction angles on theirdynamic response is explored. The results indicate that the maximum dynamic response of both the single tower and tower line system is greater than their pseudo-static response. The existence of transmission lines enhances the stability of the transmission tower line system, reducing its dynamic response. A wind direction angle of 90° proves to be the most unfavorable for the dynamic response of the single tower and tower line system.

The carbon fiber triaxial woven fabric has good application prospects in the field of space deployment devices because of its advantages of stable structure， light density and quasi-isotropic. In order to study the deformation properties of carbon fiber triaxial woven fabric/thermoplastic polyurethanes （TPU） flexible composite， TPU and carbon fibertriaxial woven fabric were composited by hot pressing. The unit cell model of triaxial woven fabric was established by metallographic microscope and SEM.The moment of inertia of different sections was calculated by the model， the moment of inertia of the weft section is greater than that of the warp， and the triaxial woven fabric is more difficult to deform in the weft direction. Drape experiments were performed on carbon fiber plain fabric and triaxial woven fabric.The results show that the deformation ability of the triaxial woven fabric is stronger than plain fabric， and the warp direction deformation of triaxial woven fabric is greater than the weft when it is draped， which is consistent with the calculation result of the moment of inertia of the model section； triaxial woven fabric is subjected to tensile tests in the 0°，15°and 30°directions， the load curve changes and ultimate loads of the three angles are analyzed at different strain stages.

Objective To investigate the risk factors and preventive strategies of pancreaticoduodenectomy postoperative hemorrhage. Methods A total of 208 patients who underwent pancreaticoduodenectomy in the Department of Hepatobiliary Surgery of the 904th Hospital of Joint Logistics Support Force, PLA from January 2017 to December 2021 were enrolled. Twenty-one patients with postoperative hemorrhage were retrospectively analyzed. Results Univariate analysis indicated that postoperative hemorrhage was mainly associated with pancreatic leakage, biliary leakage, abdominal infection, hypoproteinemia, diabetes, improper use of ultrasound knife, skeletonization, intraoperative blood loss, preoperative jaundice, etc.(P0.05). Among the 21 patients with postoperative hemorrhage, 4 cases recovered after conservative treatment such as hemostasis and blood transfusion, 6 cases underwent interventional treatment, 11 cases underwent abdominal exploration, and 2 cases died of postoperative multiple organ failure. Pancreatic leakage (OR=3.963,95%CI: 1.120-14.025), biliary leakage (OR=4.013,95% CI: 1.173-13.734) and abdominal infection (OR=7.545,95%CI: 1.833-31.051) were independent risk factors for postoperative hemorrhage. Conclusions The improvement of anastomotic manipulation, reduction of anastomotic leakage, and control and prevention of abdominal infection are important to prevent postoperative hemorrhage of pancreaticoduodenectomy. Surgical treatment should be performed as soon as possible for the patients with poor conservative treatment effect.

Pipeline-type oil-water separation technology has the advantages of small footprint, high separation efficiency and low cost. A Y-type tubular oil-water separation structure was designed based on the principle of pipeline-type oil-water separation. The effects of internal flow field and external parameters on separation efficiency of Y-tube were studied by adopting standard k-ε turbulence model and mixture multiphase flow model in Fluent numerical simulation software. The results showed that the Y-shaped tube had little disturbance to fluid, stable internal flow field characteristics and was not easy to generate eddy current, which could realize oil-water separation. There was oil-water separation at the junction of branch pipe and main pipe. The oil-water separation efficiency increased gradually with the increase of the oil droplet size. The larger of the oil droplet size, the better the oil phase will float and gather in the upper layer of Y-shaped tube, which effectively improved the oil-water separation efficiency. The inlet velocity had a great influence on the oil-water separation effect. The higher the inlet velocity, the shorter the oil phase floating time, and the lower the separation efficiency of Y-shaped tube. The separation efficiency increased with the increase of branch shunt ratio. When the inlet velocity was 0.5 m/s, the separation efficiency would not increase when the shunt ratio exceeded 0.4. The results provided a new idea for oil-water separation and a theoretical reference for the design of Y-shaped tube.

【Objective】 The Venlo-type greenhouse is commonly used in commercial horticulture due to its efficient space utilization and superior light transmission. This study investigates the impact of spire width on microclimate within such greenhouses under natural ventilation conditions. 【Method】 The study focused on multi-span glass greenhouses. We used experimental measurement and CFD modelling to simulate the variations in temperature and airflow in the greenhouse for various spire widths: 3.2 m JD3.2, 3.6 m JD3.6 and 4 m JD4 under natural ventilation conditions when the outdoor wind speed was 0 and 1 m/s, respectively. 【Result】 ① Comparing with measured temperature at different sampling points in the greenhouse reveals that the relative error of the simulated temperature ranged from 0.2% to 3.3%, ② Spire width had a significant effect on temperature distribution in the greenhouse. In particular, temperature increased upward in the greenhouses with the JD3.2 spire, while, in contrast, temperature increased downward in the greenhouses with the JD3.6 spire. ③ Regardless of the outdoor wind speed, greenhouses with JD3.2 spire had the best heat removal efficiency. The heat removal efficiency of JD3.6 and JD4 spire and the associated temperature distribution in the greenhouses was better when the outdoor speed was 0 m/s than when the outdoor wind speed was 1 m/s. 【Conclusion】 For all spire widths we compared under different working conditions, the greenhouse with JD3.2 spire work best for ventilating and cooling the greenhouse.

In response to the current problems of high startup wind speed, complex design schemes, and inability to accurately measure the average wind speed of the entire section of the roadway using wind speed sensors, based on the principle of ultrasonic opposed wind measurement, a mine opposed wind speed and direction sensor with STM32 as the core is designed. The overall structure of the sensor, the design of the transmitting and receiving circuit, the filtering algorithm, and the software process are introduced. This sensor has changed the wind measurement method from point to surface, using a single ARM core and measuring the wind speed at the centerline of the roadway through long-distance (5-12 m) ultrasonic wind measurement technology. This wind speed represents the average wind speed of the entire roadway. It greatly improves the accuracy and real-time performance of roadway wind speed measurement. A test prototype is developed based on the design scheme, and the test results in a circular wind tunnel show that the measured values of the sensor has good consistency with the standard wind speed values in the range of 0.1-15 m/s, with a measurement error of less than 0.1 m/s. It can meet the precision requirements of intelligent mines for roadway wind speed measurement.

Aviation industry is one of the eight key industries of carbon emission. The carbon emission of aviation industry is mainly affected by the carbon emission of aero-engine. Therefore, it is urgent to carry out the research on the measurement method of aero-engine carbon emission. The life cycle assessment is used as a quantitative method for the carbon footprint of aero-engines. The life cycle carbon emissions of aero-engines are divided into fuel cycle carbon emissions and material cycle carbon emissions, and statistics are carried out separately. The aero-engine system boundary is divided, the data collection that should be carried out in each stage is proposed, and the data is required. A relatively complete set of aero-engine carbon emission measurement method is obtained. The method obtained in this paper can comprehensively evaluate the carbon emissions of aeroengines from the perspective of life cycle, which can provide guidance for the measurement of carbon emissions of aeroengines throughout the life cycle, and provide a theoretical basis for emission reduction from the perspective of fuel and material.

In the rehabilitation training process of lower limb rehabilitation robots, the existence of uncertain factors such as model parameters and environmental interference will affect the accuracy of trajectory tracking of the robot. To solve this problem, an adaptive compensation control based on the radial basis function (RBF) neural network is proposed. This control method can improve the accuracy of mechanical system trajectory tracking. Firstly, a closed chain horizontal lower limb rehabilitation robot structure with four working modes and stable movement is designed. Secondly, the Lagrange method is used to solve the kinetic nominal model, the uncertainty factors such as model parameters and external interference of the rehabilitation device are separated, and the adaptive compensation algorithm based on the RBF neural network is designed for the approximate control. Finally, the Matlab/Simulink environment is used to verify the effectiveness of the control strategy. The results show that, compared with the traditional fuzzy proportional integral derivative (PID) control method, the adaptive compensation algorithm based on the RBF neural network has a faster response speed and better tracking effect in human gait curve trajectory tracking. Moreover, the peak angle errors of the hip joint and the knee joint trajectory tracking are 0.08° and 0.13° respectively, which are much less than the rotation angle of patients' lower limbs in rehabilitation exercise. A single-leg prototype experiment is designed to show that the RBF compensation adaptive controller used in the study can achieve high precision tracking results and meet the safety requirements of patients in rehabilitation training.

With the development of the gear transmission system towards complexity, multiple transmission types and high reliability, it becomes more and more important to assign the reliability of the gear transmission system quickly and accurately. In this study, aiming at the problems of incomplete consideration factors, inconsistent range of changes in different allocation methods for the same parameter, and inconvenient digital software development in existing reliability allocation methods, an improved advisory group on reliability of electronic equipment (AGREE) allocation method is proposed, the scoring allocation method is extended, and the digital characteristics of reliability allocation method are discussed. The basic reliability model and task reliability model of the complex gear transmission system are established, and the traversal algorithm of the automatic reliability model generation is studied. A digital platform for rapid reliability allocation of fixed axle gear train, planetary gear train and hybrid gear train is developed. Four independent modules, namely input module, calculation module, result display module and output module, are designed. The accuracy of the calculation results of the software is verified by comparing with the results of examples. The parametric modeling and the automatic generation of the example report for the reliability allocation of the gear transmission system are realized, and the accuracy and efficiency of the reliability allocation model are raised.

Objective To analyze the clinical features and prognostic factors of herpes simplex virus type 1 (HSV-1) encephalitis. Methods A total of 51 patients with HSV-1 encephalitis hospitalized in He'nan Provincial People's Hospital from January 2018 to September 2023 were selected, and their clinical data, laboratory and imaging examination results were recorded. The modified Rankin Scale (mRS) was used to evaluate the prognosis of patients and the recovery of neurological function after brain injury. Univariate and multivariate stepwise Logistic regression analyses were screened for risk factors of adverse prognosis of HSV-1 encephalitis. Results The main symptoms of 51 cases were fever and headache. The serological examination results showed increased white blood cell count (14 cases), increased neutrophil count (14 cases), decreased lymphocyte count (8 cases), and decreased serum sodium level (17 cases). Cerebrospinal fluid (CSF) examination by lumbar puncture showed increased CSF pressure (18 cases), increased white blood cell count (28 cases), increased protein (32 cases), and increased glucose (15 cases). There were 48 patients who underwent head MRI examination, and 43 patients (89.58%) showed obvious brain region involvement on head MRI, among which 35 patients (72.92%) with positive MRI showed typical unilateral or bilateral temporal and frontal lobe involvement, and 8 cases (16.67%) with increased cerebral pia mater enhancement. 66.67% (34/51) of the patients recovered completely within 6 months after discharge, 21.57% (11/51) of the patients had sequelae, and the fatality rate was 11.76% (6/51). There were 34 (66.67%) patients with good prognosis and 17 (33.33%) patients with adverse prognosis. Multivariate Logistic regression analysis showed age increased (OR = 1.090, 95%CI: 1.020-1.200; P = 0.023) and increased CSF glucose level (OR = 23.800, 95%CI: 23.800-1250.000; P = 0.030) were risk factors for adverse prognosis in HSV-1 encephalitis patients. Conclusions Increased aging and CSF glucose level are risk factors for the adverse prognosis in HSV - 1 encephalitis patients. In clinical practice, it is necessary to master the clinical characteristics of patients with HSV-1 encephalitis, so as to achieve early detection, diagnosis and treatment.

Since 2017, human encephalitis caused by pseudorabies virus (PRV) has been reported in 28 cases in China. The clinical symptoms include fever, headache, seizures, focal neurological loss, disturbance of consciousness, etc.. This disease has the high disability rate and fatality rate. PRV is mainly transmitted through close contact with infected pigs or their excrement, or spread via blood-borne. Patients are mostly practitioners in the live pig industry chain. Early diagnosis and treatment are critical to the prognosis of patients. Therefore, this article reviews the progress on diagnosis and treatment of human encephalitis caused by PRV, in order to improve the clinical diagnosis and treatment of this disease.

Hydrogel is an ideal material for cartilage repair, but it is difficult for artificial materials to achieve ultra-low friction coefficient of cartilage at present. The amphoteric ion anionic double crosslinked P(AAm-co-AAc-co-SBMA-co-AMPS)/Fe3+hydrogel was synthesized by using the amphoteric monomer [2-(methacryloxy) ethyl] dimethyl-(3-sulfopropyl)(SBMA) and the anionic monomer 2-acrylamido-2-methylpropane sulfonic acid (AMPS). The frictional tests were conducted in water and PBS to evaluate the effects of zwitterionic and anionic groups on the coefficient of friction (CoF). The results show that the physical crosslinking point introduced by SBMA and AMPS can improve the compressive strength of hydrogel, and achieve a low CoF (0.04) in water, In addition, it is observed that CoF further decreases to 0.015 in PBS, and the decrease of CoF is caused by the highly hydrated upper layer of hydrogel produced during PBS soaking.

【Objective】 Drip fertigation is an irrigation technique increasingly used to simultaneously irrigate and fertilize crops grown in different environments. However, calcium and magnesium in the water could react chemically to precipitate, clogging the irrigator as a result. In this paper, we experimentally study the impact of calcium and magnesium concentration on irrigator clogging in drip fertigation using brackish water and humic acid fertilizer. 【Method】 In this experiment, four types of irrigators (FE1, FE2, FE3, FE4) with different rated flow rates (1.6, 1.1, 1.4, 1.75 L/h) were selected, in which three groups of brackish water treatments with calcium ion mass concentration, with ion mass concentrations of 100, 150 and 200 mg/L (G1, G2, G3), and three groups of brackish water treatments with magnesium ion mass concentration, with ion mass concentrations of 100, 150 and 200 mg/L (M1, M2, M3). In each treatment, fertigation using local groundwater was taken as the control (CK), we measured the average flow rate in the irrigator (Dra), clogging distribution in the irrigator, the dry mass of clogging materials (DW), and mineral fraction of the clogging materials in the irrigator. 【Result】 Compared to CK, fertigation using water with elaborated Ca2+ and Mg2+ concentration and humic acid fertilizer increased Dra by 21.58% to 56.75%, and DW by 67.14% to 270.09%, respectively, with the increase depending on dripping rate and Ca2+ and Mg2+ concentration. When Ca2+ and Mg2+concentration was the same, increasing dripping rate reduced DW by 4.77% to 27.26%, with the reduction depending on Ca2+ and Mg2+ concentration. 【Conclusion】 Increasing calcium and magnesium concentration in the fertigation water significantly increased irrigator clogging. When calcium and magnesium concentration was the same, an increase in magnesium concentration significantly reduced the mass of clogged materials due to the reduced carbonate. Thus, increasing magnesium ion can ameliorate irrigator clogging and reduce the risk of irrigator blockage.

Human milk oligosaccharides （HMOs） are a group of complex glycans in human milk and play an important role in promoting the growth and development of infants, and more than 200 kinds of HMOs have been identified so far. In this paper, the types and structures of HMOs and their roles in improving infant intestinal health, promoting immune system development and brain development were reviewed. The application status of HMOs was summarized, the possibility and necessity of industrial production and application of HMOs in the future were prospected.

We report a case of a young female patient with fatigue, hypokalemia, and hyperglycemia. She had past-history of diabetes mellitus, and was admitted to hospital with a history of fatigue and hypokalemia for 5 years. The patient's examination indicated hypokalemia, hypomagnesemia, metabolic alkalosis, hypocalciuria, and SLC12A3 gene pathogenic mutation. The diagnosis was Gitelman syndrome. Potassium and magnesium supplements were given to improve the patient's fatigue. Serum potassium and magnesium were normal. The blood glucose reached standard after treatment with oral hypoglycemic drugs. This article incorporates literature review to sort out the diagnosis and treatment of Gitelman syndrome, in order to provide feasible reference for clinicians.

[Objective] To explore the nutrient characteristics and fertility status of wetland soil in the lower reaches of Lhasa River. [Methods] A total of 69 soil samples were collected from the four representative regions of Ganqu Wetland, Baga Snow Wetland, Lalu Wetland and Chabalang wetland. The values of pH, total nitrogen, total phosphorus, total potassium, total salt, electrical conductivity, redox potential, cation exchange capacity and organic matter of the samples were determined. The improved Nemerow composite index method was used to evaluate the wetland soil fertility comprehensively. [Results] (1) The pH range of the soil in the study area was 5.77~7.78, with an average value of 6.62, which was neutral. The correlation between organic matter and total nitrogen was strong, and the distribution characteristics were similar. The contents of organic matter and total nitrogen were 61.82 and 3.13 g/kg, respectively, and both were very abundant, belonging to the first level. The contents of total phosphorus and total potassium were 0.75 g/kg and 18.05 g/kg, respectively, which were moderate and belonged to the tertiary level. The total salt content is 0.92 g/kg, and the electrical conductivity is 2.97 mS/m. On the whole, the soil in the study area had strong fertilizer retention ability. (2) The soil comprehensive fertility coefficient (P) of wetland was in the order of Chabalang Wetland (2.01) > Bagaoxue Wetland (1.95) > Lalu Wetland (1.93) > Ganqu Wetland (1.86), all belonging to the fertility level. The index affecting the soil comprehensive fertility of wetland was TP, because the formation conditions of natural wetlands were similar. There was no significant difference in soil comprehensive fertility coefficient. [Conclusion] The present situation of wetland soil nutrients in the lower Lhasa River was clarified, which provides scientific basis for realizing the sustainable utilization of wetland resources in the the study area.

Deploying user-side energy storage in urban power grids is an effective solution to operational challenges such as insufficient capacity for renewable energy consumption and local overloads. Therefore， an assessment method for energy storage demand on the user side in urban power grids that considers multiple operational scenarios is proposed. The approach involves quantifying the weights between different scenarios in the urban power grid based on their frequency of occurrence and severity. Scenarios including normal operation， insufficient renewable energy consumption， and local overloads are chosen to construct a model to assess energy storage demand on the user side in urban power grids. Case studies are conducted using a 37-node model of an urban power grid in a region of Zhejiang Province. The results indicate that the method is effective in evaluating energy storage demand on the user side in urban power grids and improving the reuse rate of energy storage on the user side across various operational scenarios. Compared to methods for assessing energy storage demand in a single operational scenario， this approach significantly reduces the overall demand for energy storage on the user side in urban power grids and decreases both investment costs and operational costs.

Objective To explore the relevant relationship and specificity between the implicit and explicit loyalty of military cadets in order to provide a theoretical basis and objective indicators for a more comprehensive and objective assessment for individual loyalty. Methods E-Prime 2.0, a classic implicit association paradigm was employed to construct an implicit association loyalty test for 64 military cadets. Simultaneously, an explicit loyalty measurement was conducted using the Chinese Military Personnel Loyalty Scale. Results ① Significant implicit effect was observed in the loyalty assessment of military cadets, indicating a general tendency to perceive higher levels of personal loyalty and lower levels of loyalty to external entities. ② Explicit loyalty assessment revealed that the participants had the highest loyalty score towards the Party, the Nation, and the People (4.79±0.34), followed by the loyalty score to their profession (4.38±0.53), and the relatively lower loyalty score towards the unit and leaders (4.03±0.83). Among the 3 dimensions of loyalty, the normative loyalty score ranked highest, while continuance loyalty score took lower. ③ There were no correlations among the scores of loyalty to the Party, the Nation, and the People (r=-0.030, P=0.823), to the profession (r=-0.047, P=0.728), to the unit (r=0.050, P=0.710), or to the leaders (r=0.043, P=0.749). Conclusion The implicit effect in the loyalty assessment is significant in military cadets, and there is no significant correlation between explicit and implicit loyalty measurements. Thus, we cannot rely solely on explicit measurements to assess their loyalty attitudes.

A new type of rotary reducer is urgently needed in engineering to improve the low efficiency of single point drive operation for flat single axis photovoltaic tracking brackets, in order to adapt to complex environments and reduce costs. For this purpose, a cylindrical worm helical gear toroidal worm multi-point drive rotary reducer is designed, and performance testing and analysis are conducted. Firstly, analyze and compare the installation position and transmission mechanism of the multi-point drive rotary reducer with that of the single point drive. Secondly, the performance of the rotary reducer under rated output torque and overturning torque is numerically simulated using Romax software, and a comprehensive performance testing platform for the rotary reducer is built to test the transmission performance of the prototype under rated output torque and overturning torque. The results show that multi-point drive can withstand larger loads compared to single point drive, and the overall stability of the tracking bracket is stronger; the larger the rated output torque value, the greater the stress value of the worm gear; the overall stress value and deformation of the secondary transmission mechanism under the overturning torque meet the actual working condition requirements; the experimental test does not cause significant damage inside the reducer, and the simulation and experimental results are in good agreement. The design of the rotary reducer meets the practical working characteristics of the flat single axis photovoltaic tracking bracket under harsh working conditions, and can provide theoretical reference and support for improving the photovoltaic conversion efficiency construction of photovoltaic power stations.

ObjectiveTo investigate the prevalence and risk factors of dental caries and its related influencing factors in 12-year-old children in Yangpu District， Shanghai， and to provide relevant data support for the formulation of oral health policies and measures for children.MethodsIn 2021， 839 12-year-old children were randomly selected from five ordinary junior high schools in Yangpu District. The investigation included an oral health examination and a questionnaire survey on factors related to dental caries. Logistic regression analysis was used to analyze the influencing factors of dental caries.ResultsAmong the 839 participants， data from 830 were included. Among them， 426 were male （51.3%） and 404 were female （48.7%）. Of the 830 children， 203 had dental caries， resulting in a caries prevalence of 24.46%， a caries supplemental filling ratio of 32.6%， and a DMFT of 0.63. Multivariate logistic regression analysis revealed that a mother’s education level of college or above （OR=0.849，95% CI： 0.732‒0.984）， brushing teeth twice a day （OR=0.827，95%CI： 0.703‒0.973）， and the caregiver brushing teeth twice a day （OR=0.843， 95%CI： 0.726‒0.983） were effective factors in reducing the caries rate. Factors associated with childhood dental caries included consuming sweets ≥1 time per day （OR=1.397，95%CI： 1.197‒1.342） and female gender （OR=1.482，95%CI： 1.347‒1.671）.ConclusionThe prevalence of dental caries among 12-year-old children in Yangpu District is 24.46%. Gender， maternal education， the frequency of children's toothbrushing， the frequency of sweet consumption， and the caregiver’s toothbrushing frequency are the main factors affecting the prevalence of dental caries in children.

Bladder cancer is the most common malignant tumor in the urinary system. Currently, the clinical treatment options for bladder cancer mainly include surgery, chemotherapy, radiotherapy, immunotherapy, targeted therapy, photodynamic therapy, combination therapy, etc. The conventional treatment and administration strategies for bladder cancer primarily depend on the tumor stage and the extent of metastasis. However, in the process of non-surgical treatment, drugs lack specificity and targeting. Once the dosage is improperly controlled, drugs will damage normal cells when attacking cancer cells, which will lead to poor efficacy and multiple side effects. Nanomedicine is an emerging interdisciplinary field that utilizes nanomaterials and technologies in nanomedicine to provide disruptive technologies for traditional treatments, with advantages such as targeted delivery and high efficiency with low toxicity. Many nanotechnologies have become hot topics in clinical research in the field of medicine. Functionalized nanoparticles can actively or passively target specific cells within target organs, such as bladder cancer cells, by altering their surface properties, thereby enhancing drug delivery precision, reducing damage to normal cells, and improving treatment efficacy. This article provides an overview of the progress in classical and novel treatment approaches to bladder cancer, with a particular focus on the potential applications and future development directions of nanotechnology in the treatment of bladder cancer, providing important reference for personalized therapy and clinical translation in bladder cancer.

Predicting cracking radius is a prerequisite for determining the holes spacing of gas extraction technology by liquid CO2 phase transition cracking and permeability improvement, which directly affects the gas extraction effect. Most existing prediction methods are based on single factor analysis. In order to grasp the influence of multiple factors on the radius of liquid CO2 phase transition cracking and effectively predict the spacing between holes, ANSYS/LS-DYNA numerical simulation software is used to carry out the research on predicting the radius of coal seam liquid CO2 phase transition cracking combing with orthogonal experiments. The numerical simulation results indicate that the order of factors affecting the radius of liquid CO2 phase transition cracking is ground stress>gas pressure>coal solidity coefficient. The cracking radius decreases with the increase of stress, and increases with the increase of gas pressure and coal solidity coefficient with a linear relationship. A multiple regression analysis is conducted on the numerical simulation results. A prediction model for the radius of liquid CO2 phase transition cracking is established based on three different coupling conditions of ground stress, gas pressure, and coal solidity coefficient. Industrial experiments are conducted on the coal mine site. Extraction boreholes are set up based on the predicted model calculation results. The pressure index method is used to test and analyze the gas extraction effect. The results show the following points. The gas pressure in the observation holes on both sides of the liquid CO2 phase transition cracking hole shows a decreasing trend with time. The farther away from the cracking hole in the initial stage of extraction, the greater the gas pressure. It is consistent with theoretical analysis and numerical simulation results. The effective cracking range of liquid CO2 phase transition is basically consistent with the predicted results. The gas volume fraction in the observation hole is 73.4% higher than that in the natural extraction hole, and the gas extraction efficiency is significantly improved.

The low cycle fatigue（LCF） properties of DD6 single crystal superalloy were investigated at 700 ℃ and R of 0.05. SEM was used to study the fracture surface and fracture microstructure. The results show that the LCF life of the alloy decreases with the increase of strain amplitude. LCF properties of the alloy are excellent under asymmetrical cyclic loading. The alloy has no transition fatigue life during LCF tests at all total strain amplitudes. LCF fatigue damage can be dominantly contributed to elastic damage and the plastic deformation is very minimal. The plastic damage increases with the increase of total strain amplitude. The crack initiation site, the fatigue crack propagation area and the final fracture zone can be observed in the fracture surface and all specimens is similar to quasi-cleavage fracture. The fatigue cracks are initiated from the micro-pores on the surface, sub-surface or far from the surface. Far from the surface crack fractures have fish-eye feature. The fatigue crack propagates perpendicularly to main stress at first and then along {111} plane. Typical fatigue striation, cleavage steps and river pattern characteristic are formed on fatigue crack propagation zone. The cleavage plane, slip band and tearing ridge are seen in the final fracture zone. Fracture microstructure analysis shows that the γ′ phase morphology far from the fracture surface still maintains cubic shape， and the slip bands are visible seen near the fracture surface， and secondary cracks are formed along slip bands.

Insulation is considered the weakest link in electrical equipment. The combined effects of special working conditions in coal mines and aging factors such as electrical, thermal, and mechanical stresses make it difficult to determine the aging mechanism and evaluate the condition of EPDM insulation for high-voltage cables used in mines. This paper introduces the basic performance and aging factor types of EPDM insulation for high-voltage mobile flexible cables used in coal mines. Based on the physical, chemical, mechanical, and electrical properties of EPDM under the influence of multiple aging factors, the aging mechanism of EPDM is proposed. This paper summarizes the basic principles and existing problems of online monitoring methods for insulation resistance, partial discharge, dielectric loss factor, and temperature of mining high-voltage cables. The paper summarizes the current research status of insulation status evaluation methods for mining high-voltage cables. The paper introduces the evaluation methods for insulation status of multi parameter based on improved radar map and single parameter based on dielectric loss mining high-voltage cables. To cope with the development of coal mine intelligence, on the one hand, it is suggested to do research on intelligent perception and control of mining electrical equipment to compensate for the lack of state perception and state evaluation feature quantities. On the other hand, it is necessary to study lightweight models or algorithms to reduce the computational complexity, parameter quantity, and analysis time of intelligent terminals near devices. It improves the feasibility of state evaluation technology, and lays the foundation for achieving intelligent analysis and decision-making.

Objective To explore how to integrate the history of Peking Union Medical College (PUMC) into the teaching of diabetes in internal medicine, in order to develop an ideological and political theory-based course with PUMC characteristics. Methods The students in '4+4' medical doctor program of PUMC were enrolled into this study. Diabetes mellitus course combined with ideological and political theories course (including the history of insulin development, the life and contribution of Prof. WU Xian and Prof. LIN Kesheng, and the contributions of Prof. CHI Zhisheng, Prof. PAN Xiaoren and Prof. XIANG Hongding to the prevention and treatment of diabetes) was used for the teaching. Feedback (including the level of the political teaching knowledge before and after the course, the effectiveness of the political teaching by students after the course) was collected by questionnaire online, and statistical analysis was conducted. Results A total of 62 students (32 in grade 2020 and 30 in grade 2021) were included in the '4+4' pilot class of clinical medicine at PUMC. A total of 58 questionnaires were collected (30 in grade 2020 and 28 in grade 2021), with a rate of 93.5%(58/62). Before teaching, 55.2%~100% of the students had no knowledge of the course, and after teaching, all students had a general understanding, with the level of understanding significantly better than before (P < 0.001). According to the survey, 82.8% of the students thought that the course increased their interest in learning, 86.2% of the students were satisfied with the overall effect of the course, 89.7% thought that it allowed them to better understand the history of PUMC, 77.6% thought it deepened their understanding of the spirit of medical science, 82.8% thought it increased their understanding of the spirit of professional service to the country and patriotism, and 72.4% thought it increased their sense of social responsibility. Conclusions Integrating the history of PUMC into clinical medicine education is the unique advantage of PUMC medical education. It is conducive to students understanding of ideological and political theories, inculcation of correct values, method ology and humanistic qualities, and cultivation of the truth-seeking and pragmatic spirit of medical science.

Objective To evaluate the performance of a new fluorescence immunochromatographic assay for interleukin-6 (IL-6) detection. Methods A total of 104 serum samples from patients with suspected infections and normal population were collected at Peking Union Medical College Hospital in December, 2021. Assay A (Wanfu biofluorescence immunochromatography assay) and B (Siemens chemiluminescence assay) were used as references to evaluate the equivalence of the Innova assay for detecting serum IL-6. Meanwhile, 39 homologous paired plasma and serum were collected to evaluate the consistency of the Innova assay in detecting IL-6 content in different types of samples. Results In quantitative analysis, two samples were excluded because the content was above the limit of detection for method B. Compared with the assay A or B, the regression equations of the Innova assay were Y=-7.0950+1.1924X (R2=0.9448), Y=-2.6143+1.3072X (R2=0.9391), and the Pearson correlation coefficients were 0.9720 and 0.9691, respectively. With assay A or B as reference, the Innova assay showed the Bland-Altman bias values of -3.0 and 8.0, while the expected bias at the medical decision level (7 ng/L) was -1.44 ng/L (95% CI: -5.37 to 2.50), 1.97 ng/L (95% CI: -2.09 to 6.01), respectively, with 95% CI intervals all included permissible errors (±15%, -1.05 to 1.05 ng/L). The qualitative results showed the high total coincidence rate between the Innova assay and assay A (84.6%), and assay B (83.7%). In addition, the consistency of the Innova assay was good for 39 homologous pairs of plasma and serum samples (P < 0.0001). Only one data (2.6%, 1/39) was identified by Bland-Altman bias analysis to be outside the maximum allowable error range. Conclusions Compared with the two reference assays with the same or different principles used in clinical practice, the Innova assay for IL-6 detection has good consistency and correlation, and its test results are almost not affected by the type of serum/plasma samples. To a certain extent, the Innova assay meets the needs of rapid detection in clinical practice.

USRP (ultrasonic surface rolling processing) was used to change the surface layer of 6061 aluminum alloy, so as to realize the change of the second phase microstructure of 6061 aluminum alloy by USRP under different static pressure conditions to improve corrosion resistant, which was characterized by using scanning electron microscopy, laser confocal microscopy, scanning Kelvin probe force microscopy, etc. Based on the principle of microzone galvanic corrosion and considering the impedance of solution and oxide, the correlation law between the size of the second phase and the development of local corrosion was obtained. The effect of the size of the second phase on the development of local corrosion was verified by in-situ observation using laser confocal microscope. The results show that the initial self-corrosion current density of aluminum alloy in 3.5%(mass fraction) NaCl solution is only 1/15 of that of the untreated sample, the corrosion rate is reduced by 93.04%, when the surface layer is rolled with 0.10 MPa static pressure. The Mg2Si phase has no significant morphology change during the rolling process, and it has no significant effect on the corrosion performance before and after USRP. The AlFeSi phases with long strip continuous distribution are refined into micro- and nano-scale dispersion distributions under the action of USRP. The fully refined AlFeSi phase weakens the galvanic corrosion effect due to the reduction of the local anode/cathode area ratio of the corrosion microcell, which promotes the metastable pitting nucleation rate of the aluminum alloy matrix, but also cause the rapid dissolution of the aluminum alloy itself. When self-dissolution occurs or Al2O3 oxide film is formed in the inner wall of metastable corrosion hole, the electrochemical corrosion effect of AlFeSi relative to aluminum alloy matrix is greatly weakened, so as to improve the corrosion resistance of 6061 aluminum alloy as a whole.

Implant infection is one of the most common and serious complications in orthopedics, and it is also an important reason for the failure of implant surgery. When bacteria form a biofilm on the implant surface, it is extremely difficult to be eliminated and attracts more bacteria and fungi. A large number of studies have shown that the use of surface modification technology can effectively reduce the adhesion and accumulation of pathogenic bacteria, thereby preventing peri-implant infection. The formation process of bacterial biofilm on the surface of orthopedic implants and the antibacterial mechanism of metal antibacterial agents were first analyzed. Then, some of the most widely used metal-based inorganic antibacterial coatings at home and abroad and their related preparation processes were reviewed, the problems and improvement methods in the application of these coatings were also discussed, and the development direction of inorganic antibacterial coatings in the future was prospected, such as synergistic antibacterial coatings and bone-promoting antibacterial coatings.

Objective To investigate the demands of clinical teaching and perception of the theoretical knowledge and clinical practice among nursing undergraduates at school, and provide reference for establishment of a systematic teaching management system and improve the quality of clinical teaching. Methods Totally 161nursing undergraduates at school were recruited by a convenience sampling method, and an open-ended questionnaire survey was conducted to investigate the nursing undergraduates’ demands of clinical teaching. Results The top-ranked demand for clinical teaching was the combination of theoretic knowledge and clinical practice (91. 93%), followed by the diversified teaching methods including video-assisted and real case teaching (85. 71%) and developing students' interest in clinical work(81. 99%). Most of students were satisfied with clinical teaching. Conclusion Clinical teachers should help students build clinical thinking ability by adopting the teaching method combining theory with practice. Clinical teachers should help students build conference and establish identity and self-worth in clinical practice. (目的 调查在校本科护理学生对临床带教老师的需求, 通过了解学生的理论知识与临床实践认知, 为建立系统、完善的教学管理体系, 不断探索完善临床护理实践与理论知识的紧密结合, 从而为提高临床护理教学质量提供参考。方法 采用便利抽样法对某高校161例在校本科护理学生进行临床教学需求问卷调查。结果 在校生护生对“应将书本理论与临床实操练习相结合”的需求最高(91. 93%), 其次为“教学多样化, 如视频、真实案例等教学”(85. 71%)和“教学过程中应培养学生对临床工作的兴趣”(81. 99%)。满意度调查显示, 156(96. 89%)例在校护生对教学满意。结论 在进行临床教学时, 教师可以通过现场理论与实操教学相结合的方式, 让学生建立自己的临床思维, 老师多分享临床经验, 多鼓励学生, 在潜移默化中帮助学生建立自信心, 帮助护理实习生在临床工作中找到自我价值, 从而提高护理教学质量。)

The upper and middle reaches of the Yellow River is an important region in China characterized by ongoing conflicts regarding water resources, food, and energy. To achieve high-quality development of the region, it is essential to identify water, food, and energy security risks and propose corresponding measures. This study examines the basic implications of water-food-energy coordinated development and analyzes the new situation, opportunities, and challenges associated with the coordinated development of water, food, and energy in the region. Focusing on the goals of ecological protection and high-quality development in the Yellow River Basin, the study proposes a strategic framework for coordinating water, food, and energy development. It further proposes the following suggestions: (1) maximizing the utilization of water resources, (2) taking the energy industry as a pillar industry of the region and enhancing energy production efficiency, (3) ensuring food security by strengthening water support, (4) minimizing the negative impacts of food and energy development on water resources and ecology, and (4) innovating technological and institutional approaches to guarantee water, food, and energy security.

Owing to the feature of ultrahigh power density, the dielectric capacitors play an increasingly important role in the field of industrial production, basic scientific research, aerospace, and military industry in recent years. However, the relatively low energy storage density of the dielectric capacitors generally leads to their big sizes, which is difficult to meet the miniaturization requirements of future devices. Polymer-ceramic nanocomposites can combine high permittivity of the ceramic fillers and the excellent breakdown strength of the polymer matrix, thus achieving excellent energy storage performance. At present, developing the polymer-ceramic nanocomposites with high energy storage density is the key to realize the miniaturization goal of dielectric capacitors in the future. The current research progress of polymer-ceramic nanocomposites for energy storage capacitor applications from three perspectives was systematically summarized, including regulation of the nanofillers, optimization of the interfaces, and design of the multilayer composite structure. Notably, the influences of the dimension, size, species, hierarchical structure of the nanofillers, interface optimization methods such as surface modification and core-shell structure construction, as well as multilayer structure design such as sandwich structure and gradient structure on the permittivity, breakdown strength and the energy storage density of the nanocomposites were introduced in detail. Meanwhile, the structure-activity relationships between the microstructure of nanocomposites and their energy storage properties were further analyzed and discussed. Finally, based on the challenges and shortcomings of the current research, the important development directions of this field in the future were proposed, including selecting the new 2D nanofillers, enhancing the energy storage efficiency, employing multimode combined optimization strategy, and constructing the corresponding dielectric capacitors.

SiC fiber-bonded ceramics (FBCs), as a new thermal-structural material obtained by hot-pressing sintering of SiC fiber, has low porosity, high fiber volume fraction, high temperature resistance, oxidation resistance and high strength. It is an excellent candidate material for high temperature components such as turbine blades and rotors of aero-engine. The research progresses of FBCs were systematically reviewed in this paper. The structural characteristics and preparation methods of two types of FBCs (Tyranohex and SA Tyranohex) were introduced, the relationships among the composition, structure and performance of FBCs were discussed. It was noted that the interface carbon layer plays a crucial role in the performance of FBCs. The mechanical properties of SA-Tyranohex at room temperature and high temperature were highlighted, and the reasons for its excellent high temperature performance were analysed. The examination, verification and application development were summarized. The difficulties of FBCs in forming complex components were pointed out, and the future development trends and research directions were prospected. Finally, it was proposed that conducting research on SiC fiber-bonded ceramics is of great significance for the development of new materials for high-temperature resistant components in China.

Objective By summarizing the clinical characteristics and follow-up outcomes of 5 patients with immune checkpoint inhibitor induced diabetes mellitus (ICI-DM) and reviewing the relevant literatures, the article aims at providing reference to clinicians in the diagnosis and treatment of the ICI-DM. Methods Clinical data of 5 patients with ICI-DM who were admitted to Peking Union Medical College Hospital from December 2018 to February 2023 and did retrospectively analyzed. Results Five patients with a mean age of (65±7)years received treatment by the programmed cell death 1 (PD-1) or its ligand inhibitor (PD-L1). The median time from the first immunotherapy to the discovery of elevated plasma glucose was 100 (43, 210)days, and the median cycle of immunotherapy was 7 (2.5, 10.5). The onset of the illness of all the 5 patients started with diabetic ketosis or ketoacidosis. At the onset, urine ketone bodies were positive, random plasma glucose was (36.36±15.89)mmol/L, glycosylated hemoglobin A1c (HbA1c)was (8.6%±0.66%), arterial blood pH was (7.28±0.16), and the median fasting C-peptide level was 0.09 (0.05, 0.32)μg/L. Five patients had an onset plasma glucose level of grade 3 or 4.Then, ICI treatment was discontinued in all patients and insulin therapy started. The daily dosage of insulin was (56±20)IU, supplemented with hypoglycemic drugs. After treatment, urine ketone body turned negative, pH value increased to normal range, and random plasma glucose decreased significantly (the median difference of random blood glucose before and after treatment was 21.30 mmol/L, P=0.043) showing that the treatment was effective. During the follow-up, all patients continued to use insulin. The PD-1 or PD-L1 inhibitors were restarted after hyperglycemia remission. The tumor condition was under control. Conclusions ICI-DM mainly occurs in patients who receive treatment with PD-1 or PD-L1 inhibitors usually with acute hyperglycemia whose laboratory tests indicate insulin secretion defects. Some patients had positive islet cell antibodies, glutamic acid decarboxylase antibodies and autoantibodies.Patients with positive autoantibodies needed early diagnosis and continuous insulin treatment. ICI treatment can be restarted after endocrinologists brought the blood glucose under control.

The 4+4 Medical Doctor Program set up by Peking Union Medical College has the characteristics of diverse professional backgrounds and short learning experience of medical courses. It is a pilot project to set up an integrated course of “organ-system-function”(OSF) basic medicine in the program. Teachers try to build an autonomous learning environment through the modular object-oriented dynamic learning environment(Moodle) platform in endocrine system teaching, carry out collective lesson preparation and trial lecture system, combine with the history of medicine and the introduction to medical scientific research, in order to explore a teaching model suitable for 4+4 Medical Doctor Program. According to the questionnaire survey, 80.0% of the students are generally satisfied with the teaching effect, 45.0% suggest that the basic knowledge content should be strengthened, and 55.0% of them believe that it is necessary to increase the humanistic knowledge related to the professional content.

Geomorphic features contribute to variations in regional climate, soil, and other ecological environment factors, which are also an important basis for the biodiversity and evolution of ecosystems. Studying geomorphic features in nature reserves provides a geomorphic basis for resource and environmental management and protecting ecology and biodiversity in these areas. This study revealed the terrain variation, geomorphic patterns, and developmental evolution of the Wumeng Mountain National Nature Reserve by combining quantitative and qualitative methods by investigating geomorphic features and advanced land observing satellite (ALOS) digital elevation model (DEM) terrain analysis. The results indicated that: (1) the reserve elevation was 980~2,454.7 m, with an average of 1,859.9 m, and the undulation was 390~2,104.7 m, with an average of 1,392.1 m. The basic geomorphic types of the reserve were mainly large undulating middle mountains (57.45), large undulating subalpine mountains (30.66%), and medium undulating mesas (11.17%), with an average slope of 21.1°. The gentle slopes (34.83%) had the highest proportion, followed by slopes (31.21%) and gently steep slopes (17.57%). The area of each aspect was the highest on half shady slopes (27.92%) and the least on sunny slopes (21.70%); (2) the reserve was located at the top part of the mountain, with the slope and undulation in the middle of each area being low and the surrounding area being high. From Sanjiangkou to Chaotianma and Haiziping, the average values of geomorphic parameters, such as elevation, undulation, slope, and hypsometric integral, decreased gradually, and there was a trend of progressive reduction in planation surfaces; (3) the terrain profile indicated seven planation surface levels around the reserve. Among them, levels Ⅰ-Ⅲ were the summit surfaces and residual planation surfaces, level Ⅶ was the Jinsha River erosional terrace surface, and levels Ⅳ-VI were the planation surfaces, corresponding to the three tectonic cycles in the area; (4) the hypsometric integral of the reserve ranged from 0.197 to 0.815, with an average of 0.503, and more than 80% of the area was in adulthood of geomorphic evolution, indicating that the surface erosion dynamics of the area was strong, and there was a greater ecological risk with enhanced human activities. Consequently, future conservation planning should consider differences in the surface dynamics of areas with various basic geomorphic types. Geomorphic features form an important part of the natural ecosystems of forest reserves. The unique and rich geomorphic structure enables the conservation and development of biodiversity along with the elements of the ecological environment on which it depends. Geomorphic diversity supports the analysis of the biological formation, evolution, and persistence mechanisms in reserves and provides geomorphic evidence for studying neotectonic activity in the area.

In this experiment, the peptides were obtained by enzymatic digestion of wheat germ proteins from river sets using neutral protease, trypsin and pepsin. In vitro antioxidant capacity of samples was determined and their polypeptides distribution was determined using polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that germ protein and polypeptides concentrations were positively correlated with antioxidant capacity.The antioxidant capacity of the peptides obtained by enzymatic digestion of neutral protease at different concentrations was significantly higher than that obtained by enzymatic digestion of pepsin and trypsin (P

For the analysis of the coupling characteristics of the power system frequency dynamic and power angle oscillation, the mechanism of the two-machine system under disturbances is derived in this paper, and the mechanism of the multi-machine system is obtained based on the extended equal area criterion (EEAC). A quantitative assessment index is proposed based on the Pearson coefficient, which quantified the coupling according to the characteristics of frequency dynamics and power angle oscillation. The influence of power angle oscillation on the frequency dynamic indices is analyzed, and the coupling degrees of between the power angle oscillation and different frequency dynamic indices are assessed quantitatively. The results of the mechanism analysis and case study verify the proposed quantitative indices and show the coupling characteristics of the power system frequency dynamic and power angle oscillation, which provided guidance for optimal frequency and power angle control.

Seafloor instability and secondary submarine geohazards are widely present in the ocean, posing a threat to submarine infrastructures such as coastal port facilities, offshore drilling platforms, and submarine pipelines and fiber-optic cables. However, formation mechanisms and controlling factors of seafloor instability are still poorly understood. To improve the understanding, based on the history and development of seafloor instability, this study sorts out the common categories, global distribution, and geophysical characteristics, analyzes the formation mechanisms, controlling factors, and engineering geohazards risks, and summarizes popular quantitative analysis methods for seafloor instability. Subsequently, the application and limitations of experimental simulation technology for the slope instability process are discussed. Focused on the disaster mechanism, intelligent analysis of multi-source data, and three-dimensional monitoring of seabed instability, this study proposed the development direction and countermeasures of future seafloor instability research, aiming to provide guiding suggestions for the simulation, prediction, and warning of seafloor instability.

ObjectiveTo analyze the effect of O3 pollution on outpatient visits for respiratory diseases in a district of Shanghai.MethodsWe collected the respiratory disease outpatient data， and atmospheric and meteorological data of from a suburban general hospital in Shanghai from 2015 to 2017. A time-series analysis by generalized additive model was conducted to examine the relationship between O3 pollution and daily outpatient visits.ResultsThe daily outpatient volume for respiratory diseases was 831. The daily 8 h median concentration of O3 was 101.04 μg·m-3. The excess relative risk was 0.461% （95%CI： 0.240%‒0.682%） at lag3. Stratified by gender and age， females， child and the aged had higher risk of respiratory diseases. In the double-pollutant model， PM2.5 and PM10 increased health effects， while CO reduced health effects.ConclusionThe increase of O3 concentration can increase the daily outpatient volume of respiratory diseases.

Older population migration has become a normal occurrence that requires further systematic attention. The reasons for older migration in contemporary China exhibit a diversified trend. However, existing literature rarely discusses the impact of migration reasons on the settlement intention of the mobile older population. In China, where the aging demographic is increasing, the residence choice of the older floating population with their families presents a significant difference among cities and regions. Therefore, from the perspective of comparative analysis, to address the gap in the literature, there is an urgent need to reveal the influence mechanism of the settlement intention of the floating older population under different categories of reasons for mobility. Such an approach is of great significance for local governments to conduct differentiated management of the floating older population according to local conditions, provide equal health care services for older people, and promote a new wave of urbanization. In addition to continuous aging and urbanization in China, the migration reasons and characteristics of the older migrant population are diversified. While family migration is still the main reason for the mobility of older people in China, there is an increasingly evident demand for off-site pension, which presents new requirements for the government to actively respond to the aging and carry out services for different kinds of migrant older people. This study explores the influence mechanism of two typical mobility reasons (off-site pension and family migration) on the settlement intention of migrant older people. We adopt the multi-level logistic regression model based on the 2017 China Migrant Population Dynamic Survey. This study derives the following main results. First, the settlement intention of off-site older people is significantly promoted, while the intentions of the family accompany-migrated older people are not convincing. The intention of the former is 14.3% higher than the latter. Second, personal and family characteristics (demographic factors, socioeconomic status, social integration status) and inflow characteristics (urban scale, urban public services, urban environment) both affect the settlement intention of migrant older people. Third, there are different mechanisms for the settlement intention of migrant older people with different reasons for migration. The family is the core of the settlement choice for family migration, while the livability of the environment mitigates its effect. Fourth, the settlement choice of the off-site older people depends on the purpose of personal pension. This kind of migrant older people focus more on external conditions such as favorable policies of urban agglomeration and convenient pension facilities. They will be more easily affected by the social network connection of the inflow place. An in-depth understanding of the migration reasons and characteristics of migrant older people can aid in the provision of better public services. The conclusions of this study provide a reference for local governments to carry out differentiated governance of migrant older people, promote new urbanization, and equalize public services.

Cultural memory is a spiritual, inner, and middle world composed of self-consciousness, memory, and behavior that expresses the cultural phenomenon, local emotions, and identity generated by human practice in the present world space. Geography pays more attention to the human-land relationship and spatial perception in the formation of cultural memory and constructs a unique cultural memory space. This space is the agglomeration of figurative cultural relics in space, as well as the spiritual representation of non-figurative places, such as art, text, and folklore in space. By systematically analyzing the theory of cultural memory, this study summarizes the process of evolution and development context of cultural memory. Based on 1,527 key domestic and international studies on geography, this study analyzes the main content and progress of global cultural memory space research from the perspective of keyword co-occurrence clustering, theme path evolution, and research trend, with the assistance of CiteSpace—the bibliometrics and visualization tool. By reviewing the frontier hot spots of cultural memory space research at home and abroad, this study aims to construct a research paradigm of cultural memory from the perspective of geography, improve the research methods of cultural memory, and provide a reference for the local application and multidisciplinary integration of cultural memory theory. The analysis results focus the research topics of foreign cultural memory space primarily on: 1) the memory representation of the landscape of daily life; and 2) political and ritual studies in memory. Domestic research topics primarily include: 1) cultural and local studies in collective and social memory; 2) research on urban and rural memory carried by space; and 3) research on heritage memory reproduction, promoted by cultural tourism. The literature on cultural memory space at home and abroad has gradually increased in recent years, as has the attention paid to memorial landscape, heritage buildings, ritual celebrations, war trauma, and national memory; however, the research on cultural memory space has not formed a specific theoretical paradigm. Most of the literature only focuses on the integration of cultural memory and other fields, and relatively few studies address the connotation of cultural memory space, media conversion mechanisms, and spatial identification methods. The perspective of the content and trends in domestic and foreign research indicates that Western scholars pay more attention to the study of migration, rights, free will, women, power politics, and war trauma. The focus on space is mainly on cities, emotions, and rights. Domestic geographers focus on deconstructing regionalized and China-seized cultural memory and local identity from the intangible carrier of memory. Most studies are based on obvious policy orientations. War sites, red tourist sites, traditional villages, characteristic folk customs, and festival ceremonies have become important themes in the study of cultural memory space. In the future, geography research should depict the practical process of text, ritual, and language through non-representational means and re-introduce memory into human research in a materialized way. Simultaneously, the connotation of urban and rural cultural memory should be clearly defined, and heritage, immigration, and tourism should be adopted as the new themes of cultural memory space research through digital images.

The development history, market overview and development status of viscosity index improver for hydrogenated styrene-diene copolymer at home and abroad were systematically summarized with 38 references, and the basic classification, performance characteristics and preparation methods of viscosity index improver were briefly discussed. Finally, the development direction and trend of hydrogenated styrene-diene copolymer viscosity index improver in the future were pointed out.

In recent years, arginine has received extensive attention from researchers and scholars in the field of food and nutrition because of its important role in patients' postoperative recovery and cardiovascular health. This article describes the metabolic pathways, physiological functions, absorption and intake of arginine, summarizes the application of arginine in clinical research and food for special medical purpose, and the future direction of development and research of the food for special medical purpose is also prospected.

Urban creative networks, as distinct forms of production networks, differ from inter-firm-based urban networks. It is featured by flexible production, "temporary cooperation" and being "people-centered." This study attempts to address the concept of the urban creative network in theory, and based on the basic database of Chinese digital music, it integrates the social network, Geographical Information System (GIS) spatial analysis, and econometric model to empirically analyze the structural evolution characteristics and influencing factors of the creative cooperation network of Chinese singers in the past 40 years, which enriches the theoretical and empirical study of urban networks from the perspective of creative individual connections. The results suggest the following: (1) The scale of Chinese urban digital music collaborative networks grows rapidly and shows the characteristics of low density and a "small world", and network density is negatively correlated with network scale, with obvious social network properties. (2) The collaborative network as a whole presents a "core-periphery" structure and the development trend of polycentricity and high-centricity cities are mainly located in the eastern region, with relatively low centrality in the central and western cities, and gradually forms a triad structure of Beijing-Hong Kong-Taipei. (3) The evolution of the digital music cooperation network is characterized by both path dependence and path creation, and the main form of network extension is hierarchical diffusion, with the early high-intensity links between Hong Kong and Taiwanese cities gradually being replaced by mainland cities. (4) The coverage of city ties in the cooperative network expands with an uneven spatial distribution, and high-intensity ties are mainly concentrated in the eastern cities. Over time, the core cities' control over network resources through inter-high-intensity ties weakened. (5) The cooperative network has an obvious community structure, and the communities of this coproduction network appear to be expanding, grouping, and hierarchical, with dual-core and multi-core models as its main spatial organization modes. (6) A negative binomial regression model analysis shows that the scale of the urban economy, industrial structure, and the level of the network economy have significant impacts on the network structure, while the roles of human capital, opening up, urban administrative level, and traffic accessibility are not evident, indicating that the Chinese music cooperation network has obvious endogenous mechanisms and local embeddedness. The findings of this study provide in-depth theoretical and policy insights for understanding intercity interactions and promoting the development of creative industries under the influence of the creative (digital) economy. First, a study on city networks based on the production networks of digital creative industries should focus on the characteristics of creative production networks and the role of creative actors (people). Second, policymakers should fully understand the characteristics of digital creative production sector actors and production modes when formulating policies for the development of digital creative industries and choose development paths that fit the advantages of local resources to realize industrial development. Finally, we propose a future research agenda for urban creative networks.

When the gears work under high-speed and heavy-load conditions, the effects of friction and wear cannot be ignored. The gear modification can reduce gear wear and surface temperature, and has a significant effect on improving the anti-scuffing ability of gears. Thus, the heat distortion and modification of gears are studied. Based on the basic theories of gear meshing principle and gear modifying principle, the following studies have been made: a parametric model of gear thermo-mechanical coupling is established using the finite element simulation software; the steady-state heat balance equations for each face of the gear teeth are determined, and the finite element simulation software is used to automatically impose convection boundary conditions and frictional heat fluxes on each point of the gears. By solving the temperature field of the gear, the influence of gear tooth temperature change on gear deformation is analyzed, and gear modification technology is studied. The calculation formulas of elastic deformation, thermal deformation and thermo-mechanical coupling deformation are derived. The results show that the modification can reduce the gear temperature and improve the scuffing strength of the gear.

【Objective】 The geometry of side ventilation windows is an important design parameter of greenhouse and this paper investigates the impact of their aspect ratio on air circulation in terraced greenhouses. 【Method】 The study is based on butterfly windows of terraced greenhouses in Guangzhou, using numerical simulation and experimental data measured from a greenhouse (Window C). We modelled five aspect ratios and compared the numerical simulations with experimental data. Air circulation in the greenhouse is quantified using non-uniformity coefficients. 【Result】 The average errors between the simulated and measured temperature and wind speed are 2.48% and 8.76% respectively, and their associated root mean square errors are 1.10 ℃ and 2.1×10-3 m/s, respectively. Changes in the aspect ratio do not result in significant effect on average temperature in the greenhouses, but affect temperature variation noticeably. Among the five aspect ratios we compared, Window A gives the greatest average wind speed and highest wind uniformity coefficient. Compared with Window C, it increase average wind speed by 23% and the wind speed uniformity coefficient by 41%. 【Conclusion】 Our results show that reducing the aspect ratio of the side ventilation window as currently used by local farmers can effectively increase the uniformity of both temperature and wind speed in the greenhouse.

Objective: To identify mildew maize kernels accurately. Methods: A novel method to identify mildew maize kernels using spectral variables and color characteristics of hyperspectral images. Firstly, image segmentation, spectral variables and color features extraction were carried out on maize kernel images. Then, color features of maize kernel images were utilized to generate color histograms. Additionally, spectral variables and color histogram features were combined into a feature set. Finally, the distance functions were used to analyze the features in this feature set to identify mildew maize kernels. Results: For the proposed method, the maximum average identification deviation and accuracy for the mildew maize kernels were 1.12 and 97.59%, respectively. Compared with the method based on hyperspectral images + random frog + extreme learning machine, the method using hyperspectral images + colony optimization + BP neural network, and the method based on hyperspectral images + sparse auto-encoders + convolutional neural network, the identification accuracies of mildew maize kernels were significantly improved by the proposed method. Conclusion: The developed method can accurately identify whether the corn grain samples are mildew and the mildew degree of the maize kernel samples.

Taking gob-side entry retaining in Sichuan Coal Group Xuyong No.1 mine as an engineering background, the displacement inverse analysis method is used to calibrate the physical and mechanical parameters test results of coal and rock, and the numerical simulation method is used to analyze the mine pressure distribution law of gob-side entry retaining roadway. Field observation shows that during the working face mining, the maximum relative displacement of roadway roof and floor is 743 mm. Roof subsidence is the main displacement mode of roadway roof and floor. The average roof subsidence is 3.6 times of floor heave, and the numerical simulation result is 3.5 times. The parameter calibration results show that the reduction of elastic modulus and cohesion has a significant impact on the roof and floor approach. At the same calculation step, the roof and floor approach increases with the decrease of elastic modulus and cohesion. When the elastic modulus is reduced to 20%, the maximum value of roof and floor approach increases to 800 mm. The numerical simulation results show that the abutment pressure at the high wall of gob-side entry retaining roadway at the rear of mining face increases significantly, and the abutment pressure distribution is low on both sides and “convex” with the middle height, and the peak value of abutment pressure increases with the advance of working face. The influence range of the average leading abutment pressure of the working face is 77 m.

The high voltage cable used in mine is affected by many factors, such as electricity, heat and machinery stress. These factors accelerate insulation aging and easily lead to cable leakage, short circuit or discharge. At present, the dielectric response method is introduced into analysis, evaluation and diagnosis of insulation performance and aging state of mine cables. In view of problems of insulation performance and aging state evaluation of mine cables, the commonly used ethylene propylene diene monomer (EPDM) insulated mobile flexible cable for mining is taken as the research object. The basic principles and typical characteristics of recovery voltage method, polarization/depolarization current method and frequency-domain dielectric spectroscopy method in dielectric response method are summarized. The advantages and disadvantages of the three methods are compared. The characteristics of cable insulation performance evaluation based on the dielectric response model are introduced. The characteristics include the aging factor extracted by the extended Debye model, relaxation characteristics extracted by the modified dielectric relaxation model and dielectric loss integral spectrum. The application of the dielectric response method in the evaluation of the insulation performance of mine cables is summarized from the following aspects. The aspects include the identification of trace corrosion degree of mine cables based on recovery voltage method and polarization/depolarization current method. The aspects include the evaluation of EPDM insulation multi-stress aging state based on polarization/depolarization current method and isothermal relaxation current, based on dielectric relaxation model and based on dielectric loss integral value. The existing online monitoring technology for the evaluation of the insulation performance of mine cables based on the dielectric response method cannot adapt to the working conditions of coal mines. The evaluation data is insufficient, and the relationship between the insulation deterioration degree and the characteristic quantity is unknown. In order to solve the above problems, this paper puts forward that the research should focus on two key technologies, namely, cable insulation state perception and the relationship between insulation degradation degree and characteristic quantity construction.

ObjectiveFocused on the laboratory animal domestication and breeding of domestic cats, to explore the feeding management methods and breeding techniques of experimental cats.MethodsSeven Chinese garden cats from three litters were introduced from the rural suburbs of Guangzhou, and a breeding seed colony was established. The cats were domesticated in captivity, bred, closed breeding and transmission according to the feeding and management methods of laboratory animal. The population reproduction, the number of pregnancies per year, the litter season, the birth and weaning quality of the cats, and the survival rate of weaning were statistically collected.ResultsThe young breeding cats were able to adapt to the cage feeding management. In the transmission breeding and the expanded breeding colony, the number of female cats pregnant with one, two or three litters a year accounted for 63.2%, 26.3% and 10.5%, respectively. The proportions of litters born from the 1st to the 4th quarters were 20.7%, 20.7%, 27.6%, and 31.0%. A total of 29 pregnancies and 101 kittens were got from 19 female cats, with an average of (3.5±1.33) kittens per litter. The birth weights of female and male cats were (89.31±13.69) g and (93.47±15.12) g, respectively. Sixty-seven kittens survived from weaning. The average survival rate was 60.86%, and the weaning weights of female and male cats were (361.62±82.77) g and (376.0±91.71) g, respectively.ConclusionDomestic Chinese garden cats can adapt to laboratory animal feeding and breeding rules, and have strong fertility. They can normally pregnant and breeding throughout the year. The kittens grow to 5-6 months of age can meet the weight requirements for the examination of pharmaceutical hypotensive substances, and can be used as experimental cats for pharmaceutical examination with clear origin.