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In recent years， there have been several serious incidents involving explosions and fires in on-load tap changers （OLTCs） of converter transformers during the adjustment. To address this issue， a novel design solution for a split type OLTC is proposed， separating the switching part from the transformer body to effectively prevent the faults in the tap changer being intensified. The vacuum permanent magnet switch replaces each contact of the switch， and the operating mechanism is independently configured. Based on current sampling devices arranged in the internal circuit， monitoring and control of the switching process are achieved. Split type synchronous control logic and step control logic for the diverter switch are introduced to monitor the status and provide fault protection during the tap changer adjustment process. Experimental results from the prototype validate the feasibility and effectiveness of the proposed OLTC design for converter transformers.

Mr. Zeng Zhaoxuan was a famous geographer, geomorphologist, and educator in China and one of the first winners of the "geographical science achievement award" of the Chinese Geographical Society. He developed theories such as the stage development theory of flowing water topography and stage model of coral island development, and academic terms such as "stone egg" "collapse hill" "alluvial Delta" and "Danxia landform". His achievements filled the research gaps in the fields of landscape geography, historical geomorphology, and human geography. The research fields involved many disciplines such as geography, geomorphology, geology, ocean, biology, history, human, local chronicles, and cities. This study deeply analyzes his academic works, adopts the life path method of time geography to establish the academic life path according to the time latitude, and combines the academic tree method to construct his academic landscape. During his 60 years of teaching and scientific research, Mr. Zeng made indelible contributions to China's geographical science research and geographical education. First, he actively engaged in education and compiling teaching materials. While teaching and educating people, Mr. Zeng compiled a number of teaching materials for colleges and universities with wide influence. He wrote and published Geomorphology with Mr. Yan Qinshang, which won the first prize for excellent teaching materials from the State Education Commission in 1988. The textbook is easy to teach and learn, simple, and easy to understand; its research content covers a wide range, and the selected materials and achievements are novel. It is considered "shallow, broad, and new". He also compiled many teaching materials such as Comprehensive Physical Geography, Fundamentals of Geomorphology and Principles of Geomorphology. Second, he participated in the national scientific investigation work and successively participated in mountain investigations in Taiwan, geomorphic division and coastal investigation in Guangdong, investigation of Shiwandashan, investigation of karst areas in Southwest Guangxi, and a comprehensive investigation of the Pearl River Delta. Third, he dared to express his opinions, open up and innovate, and actively wrote academic papers. In scientific research, Mr. Zeng defied public opinions and actively published papers whenever he met different opinions, and expressed his unique views. He had profound knowledge, broad interests, sharp thinking, and worked hard work. He was an innovative and productive outstanding scholar.

Coupling of surface plasmon polaritons (SPPs) supported by graphene and hyperbolic phonon polaritons (HPPs) supported by hyperbolic materials (HMs) could effectively promote photon tunneling, and hence the radiative heat transfer. In this work, we investigate the polariton hybridization phenomena on near-field radiative heat transfer (NFRHT) in multilayer heterostructures, which consist of periodic graphene/α-MoO3 cells. Numerical results show that increasing the graphene/α-MoO3 cells can effectively enhance the NFRHT when the vacuum gap is less than 50 nm, but suppresses the enhanced performance with larger gap distance. This depends on the coupling of SPPs and HPPs in the periodic structure, which is analyzed by the energy transmission coefficients distributed in the wavevector space. The influence of the thickness of the α-MoO3 film and the chemical potential of graphene on the NFRHT is investigated. The findings in this work may guide designing high-performance near-field energy transfer and conversion devices based on coupling polaritons.

ZnO is currently the main coating material for piezoelectric bolt sensors, which exhibits excellent acoustic-electric signal conversion because of its unique piezoelectric effect, but its high-temperature structure and performance stability have been less studied. In this paper, ZnO piezoelectric coating that could generate ultrasonic longitudinal waves was prepared on （100）Si and industrial titanium bolts by RF magnetron sputtering, and annealed at different temperatures and different time durations to investigate the effects of high-temperature annealing treatment on the structure and properties of the coating. The results of scanning electron microscopy show that the annealing treatment below 600 °C does not affect the microscopic morphology of the coating surface, and the cross-sectional morphology of the coating shows a columnar crystal structure, and the columnar crystals tend to merge with the temperature increased. The results of atomic force microscopy show that the surface roughness of the coating varies by ±4 nm, and the X-ray diffraction results show that different annealing temperatures do not affect the crystal structure of the coating significantly. The acoustic signals of the bolt samples after annealing treatment at different temperatures and durations are examined, and the results show that the coating surface is intact after annealing treatment at 500 °C and below, and the bolt coating is completely peeled off after annealing treatment at 600 °C. The ultrasonic signals characterize that the structure of coating is stable after annealing at 500 °C or below; at 300 °C, after a long annealing treatment, none of the excitable ultrasonic properties of the bolt samples are destroyed, indicating that the ZnO coating can serve in the temperature range of 300 ℃ for a long time.

The Laodonggou gold deposit is a medium-sized gold deposit discovered in the eastern section of the Beishan metallogenic belt. It resulted from the superposition of multi-phase and multi-stage metallogenesis. Due to its complex deposit genesis, the deposit has five sections, of which skarn orebodies dominate Section III. Skarn minerals are mainly garnet, which can be divided into early and late phases, with early garnet having more oscillatory ring bands. We systematically studied the two types of garnet by detailed microscopic observation and electron microprobe. The core of the early garnet primarily consists of essonites, and the edge is calcium–iron to calcium–aluminum composition. Andradites dominate the late garnet. The chemical composition of garnet indicates that the early skarnization stage is under a moderately acidic and weakly oxidizing–to–weakly reducing hydrothermal environment, while the iron content increases in the later stage and the oxygen escape increases, resulting in increased alkalinity and oxidation. The garnets in Section Ⅲ, originating from hydrothermal metasomatism, belong to the andradite–essonite series. Essonites and andradites prevail in the early stage, accompanied by copper mineralization. With the late hydrothermal environmental changes, andradites increase, and pyrite mineralization and arsenopyrite mineralization increase as well, resulting in gold-rich mineralization.

Objective: To study and optimize the extraction technology of bacteriostatic extract from Indocalamus leaves. Methods: The extracts were drawn from Indocalamus leaves by ultrasound-assisted, refluxing and immersing method with extraction solvents: water, ethyl acetate, pH 4 of hydrochloric acid solution, pH 4 of acetic acid solution, pH 10 of ammonia solution and different volume ratio ethyl alcohol. The tests were carried out to analyze the antimicrobial effects with indicator bacteria Bacillus subtilis, Pseudomonas aeruginosa, Shigella Dysenteriae and Salmonella typhi and the total bacteriostatic circle was as inspection indicator, to find out the best extraction solvent and the best extraction method. Using water as extraction solvent, ultrasonic extraction method as method, an orthogonal test L9（33） was carried out by adjusting three impact factors. The impact factors were liquid-solid ratio, sonication period and sonication frequency. The orthogonal test found the optimal extraction process parameters and obtained the best extract. At the same time, the antimicrobial effect of the extract obtained under the optimized conditions was investigated according to the standard series of reference substances. Results: The results showed that water was the best solvent, and ultrasound-assisted method was the best method. The best extraction process parameters were as follows: the ratio of liquid to solid was 16∶1 （mL/g）, ultrasonic frequency was 4 times, ultrasonic period was 55 minutes. The inhibitory effect of the best extract on Bacillus Subtilis and Salmonella Typhi was equivalent to the effect of 0.01 and 0.03 mg/mL gentamicin, respectively. The bacteriostatic effects on Pseudomonas Aeruginosa and Shigella Dysenteriae were greater than that of 0.05 mg/mL gentamicin. Conclusion: The water ultrasonic method is an effective method for extracting antibacterial substances from Indocalamus leaves, and the inhibitive effect of the extract on Bacillus Subtilis, Pseudomonas Aeruginosa, Shigella Dysenteriae and Salmonella Typhi is remarkable.

At present,the mainstream diagnosis of depression is through the communication between doctors and patients,filling in the relevant questionnaire,which needs corresponding clinical knowledge and is subjective.It brings a lot of challenges to the diagnosis of depression.Using information processing technology to analyze physiological signals and build an accurate and objective auxiliary diagnosis model is of great value.However,the sample size of the public data set of depression auxiliary diagnosis is generally small,which makes the accuracy of auxiliary diagnosis is generally low.On this basis,this paper proposes a graph neural network (GNN) method for depression recognition based on data augmentation and model ensemble strategy.The method uses 128 channel EEG signals of 53 subjects and segments the collected EEG data.After data augmentation,Pearson correlation coefficient is used to calculate the correlation between different channels to construct a brain network,graph neural network is used to learn the features of brain network,and the final prediction results are obtained by majority voting with model ensemble strategy.Experimental results show that the proposed method improves the classification ability of the network and solves the problem of poor classification performance caused by small sample size.The proposed method achieves 77% classification accuracy on the MODMA data set(including 24 patients with depression and 29 normal controls) provided by the Pervasive Sensing and Intelligent Systems Laboratory of Lanzhou University.The classification accuracy of the proposed method is significantly improved compared to other methods.

Abstract Neuroinflammation occurs early in Alzheimer’s disease (AD). The initial stage of AD is related to glial dysfunction, which contributes to impairment of Aβ clearance and disruption of synaptic connection. CEBPβ, a member of the CCAAT-enhancer-binding protein (CEBP) family, modulates the expression of inflammation-associated genes, and its expression is elevated in brains undergoing degeneration and injured brains. However, the mechanism underlying CEBPβ-mediated chronic inflammation in AD is unclear. In this study, we observed that increases in the levels of nuclear CEBPβ facilitated the interaction of CEBPβ with the NFκB p65 subunit, increasing the transcription of proinflammatory cytokines in the APP/PS1 mouse brain. Oral administration of nanocarrier-packaged carnosic acid (CA) reduced the aberrant activation of microglia and astrocytes and diminished mature IL-1β, TNFα and IL-6 production in the APP/PS1 mouse brain. CA administration reduced β-amyloid (Aβ) deposition and ameliorated cognitive impairment in APP/PS1 mice. We observed that CA blocked the interaction of CEBPβ with NFκB p65, and chromatin immunoprecipitation revealed that CA reduced the transcription of the NFκB target genes TNFα and IL-6. We confirmed that CA alleviated inflammatory mediator-induced neuronal degeneration and reduced Aβ secretion by inhibiting the CEBPβ-NFκB signalling pathway in vitro. Sulfobutyl ether-beta-cyclodextrin (SBEβCD) was used as the encapsulation agent for the CA-loaded nanocarrier to overcome the poor water solubility and enhance the brain bioavailability of CA. The CA nanoparticles (NPs) had no obvious toxicity. We demonstrated a feasible SBEβCD-based nanodelivery system targeting the brain. Our data provide experimental evidence that CA-loaded NPs are potential therapeutic agents for AD treatment.

In this work, the effect of common functional groups, namely hydroxyl, formyl, carboxyl, and amine groups on the interfacial behavior of surface-modified glass fiber-reinforced epoxy is investigated at molecular scale. The interfacial properties of the epoxy/silica coated with different functional group systems are quantified by performing pulling test using the steered molecular dynamics simulations. It is found that the system with hydroxyl groups has a relatively lower interfacial interaction, exhibiting an adhesive failure mode. When partial hydroxyl groups are replaced by carboxyl, amine, and formyl groups, respectively, the interfacial interactions are increased and these systems exhibit a cohesive failure mode where failure happens in the epoxy close to interface. A relatively higher force is required for the adhesive debonding, while more energy can be dissipated for the cohesive debonding. Because the increased interfacial interactions can prevent the mobility of polymer chains, and delay the propagation of micropores in the matrix, leading to the epoxy matrix with a high ability of energy absorption. Our work provides an insight into how functional groups affect the interface debonding behavior of glass fiber-reinforced epoxy, offering a guideline for control of the interfacial properties of such composites through surface modification techniques.

In order to study the dynamic mechanical properties of SUS304 stainless steel commonly used in rail vehicles, tensile tests under wide strain rates of 0.000 2 s-1～500 s-1 were carried out respectively. The test results show that SUS304 stainless steel exhibits strain hardening during dynamic stretching. As the strain rate increases, the material exhibits a strain rate strengthening effect. At the same time, a certain thermal softening effect is produced. To accurately describe the dynamic mechanical properties of the material, the Johnson-Cook model of the material at room temperature was first established. On this basis, adiabatic temperature rise is introduced, and a modified Johnson-Cook model considering plastic strain and strain rate correlation is established. The modified Johnson-Cook model can better describe the dynamic mechanical characteristics of SUS304 stainless steel, which is the characteristic that the stress gradually weakens with the increase of strain and strain rate. This modified model provides a basic basis for the crashworthiness analysis of the rail vehicle body structure.

In order to more accurately grasp the health status of key parts of heavy-haul wagon, the crack initiation life of the structure under existing service conditions is one of the important links of the research. In order to accurately analyze the fatigue crack initiation life of heavy-haul wagon coupler knuckle, an analysis manner of fatigue crack initiation life based on the separated body model is proposed. Firstly, the uniform load model based on strain test points, the contact force model based on contact nonlinearity, and the load distribution model based on load-bearing characteristics were constructed respectively, three types of knuckle crack initiation life models under different load conditions; Then, the finite element simulation under the three load-bearing conditions and bench test results of the knuckle are compared and analyzed, and it is proved that the elastic strain calculation results of each test point in the uniformly distributed load model based on strain test points are in good agreement with the results of bench test; Finally, based on the uniform load model and the local stress-strain method, the fatigue crack initiation life analysis of the heavy-haul wagon coupler knuckle is carried out. It shows that the dangerous part of the knuckle fatigue damage is the roots of the upper and lower traction flanges. Under specific load spectrum conditions, 95% confidence and 90% survival rate, its fatigue crack initiation life is 12 200 kilometers.

In order to accurately obtain the fracture mechanics parameters of the cast E-grade steel material,and to study the crack propagation law and influencing factors of material,a fatigue crack growth test of the CT specimens of the cast E-grade steel was carried out. The Paris formula was used for characterization. Taking the crack growth calculation model of CT samples as an example,the fatigue crack growth length and load cycle period results of 5 groups of samples were calculated by using the M-integral numerical method. The relative error was within 10%,which had better consistency. Through further comparison and analysis of the reasons for the error between the test and the simulation,it is shown that the load amplitude is the main error factor,and the initial crack position,propagation rate parameters,and crack length parameters have little effect,so as to provide a reference for the prediction of three-dimensional fatigue crack propagation rules for complex structures.

Using the vibration excitation spectrum of IEC61373, the subway bogie obstacle detector was taken as the research object. The random vibration fatigue strength of the obstacle detector was studied by combining the finite element method and bench vibration test, and the remaining life at the fatigue weak points of the aluminum beam welded joints was predicted. Based on the frequency domain method, combined with Miner’s linear accumulation damaging theory, the simulation life results of the obstacle detector under acceleration excitation were obtained, then compared with the bench vibration testing results to verify the accuracy of the fatigue simulation analysis. Moreover, the sub-model boundary technique was used to separate the aluminum beam, and the stress spectrum of the fatigue weak points was equivalently converted. At last, the remaining life was predicted after inserting the initial cracks at the evaluation points. The result indicated also that it is reasonable to evaluate the remaining life of aluminum alloy welded joints with initial cracks based on fracture mechanics, which provides the certain reference for engineering applications.

Structural variations in gastric cancer impact progression. Here, the authors perform whole-genome sequencing on 168 gastric cancer patients and identified tandem-duplications of super-enhancer ZFP36L2 in 10% of gastric cancer, and mutational signatures in tumors with cadherin 1 mutations that associated with poor prognoses.

Objective To investigate the relationship between hypothyroidism and endometrial carcinoma, and to explore the relationship of the differentiation degree of endometrial carcinoma, the expression of estrogen receptor (ER) and progesterone receptor (PR) in cancer tissues with thyroid function of patients with endometrial carcinoma. Methods We collected 113 patients with endometrial carcinoma treated in our hospital from January 2015 to July 2018. A total of 156 women whose age matched with endometrial cancer group underwent physical examination in the physical examination center of our hospital during this period were randomly selected as control group. Serum thyroid stimulating hormone (TSH) and thyroid hormone (FT4) were measured. The prevalence of hypothyroidism was compared between the two groups. The expression of ER and PR in the excision specimen of cancer tissues were detected by immunohistochemistry. We analyzed the relationship of the differentiation degree of endometrial carcinoma, the expression of ER and PR in cancer tissues with thyroid function of patients with endometrial carcinoma. Results The prevalence of hypothyroidism was higher in the endometrial carcinoma group than that in the control group (P < 0.000). The TSH of patients with poorly-differentiated endometrial cancer was higher than that of patients with moderately-differentiated endometrial cancer (P=0.025). There was no significant difference in TSH and FT4 between ER, PR positive and negative in the cancer tissues of patients with endometrial carcinoma (P > 0.05). Conclusion Hypothyroidism is associated with endometrial cancer.

To study the change of grain size for the hot extrusion deformation of half shaft bushing,according to the dynamic recrystallization theory,the paper establishes the dynamic recrystallization model of material and uses the finite element analysis software Deform-3 D to study the shape of half shaft bushing in the mold work under the condition of different variation of hot extrusion deformation process of material grain size. The results show that while doing the extrusion in the shape of straight line and circular arc and spline curve with three kinds of work,the grain sizes are at different levels of detail. The circular mold material makes grain size smaller and more symmetrical. The result has important significance on the improvement of performance and quality of the sleeve.

In order to study the nonlinear deformation behavior of bolt-flange-joined laminated coupling under three different load forms of tension, bending and torsion load, a local finite element model of the coupling is established. The effects of bolt preload and interfacial friction coefficient on the deformation of the laminated coupling and the stiffness of the bolt flange connection are analyzed. The relationship between the radial or circumferential slip and the nonlinear deformation of the coupling is discussed. The results show that reducing the preload and friction coefficient can effectively reduce the lateral and torsional stiffness of the laminated coupling, but the influence on the bending stiffness is limited. The friction coefficient and the bolt preload have a similar influence mechanism on the torsional stiffness. Research results can provide a useful reference for the design of laminated coupling.

The identification of seed vigor is of great significance to improve the seed germination rate, increase crop yield, and ensure product quality. In this study, based on a hyperspectral data acquisition system and an improved feature extraction algorithm, an identification model of the germination characteristics for corn seeds was constructed. In this research, hyperspectral data acquisition and the standard corn seed germination test for Zhengdan 958 were carried out. By integrating the hyperspectral data in the spectral range of 386.7–1016.7 nm and the first derivative information of the spectral data, the root length prediction for corn seeds was successfully completed. The data regression model and prediction relationship between the spectral characteristics and seedling root length were established by principal component regression, partial least squares, and support vector regression. The first derivative information of the hyperspectral data was obtained by comparing the prediction model results with the original spectral data, which was preprocessed by Savitzky–Golay smoothing, multiplicative scatter correction, standard normal variate, and curve fitting. The results showed that the prediction model based on the first-order differential spectral data showed better performance than the one based on the spectral data obtained by other processing algorithms. By comparing the prediction results using different data characteristics and regression models, it was found that the hyperspectral method can effectively predict the root length of the seed, with the coefficient of determination reaching 0.8319.

Methionine adenosyltransferase 2 A (MAT2A) and MAT2B are essential for hepatic stellate cells (HSCs) activation. Forkhead box M1 (FOXM1) transgenic mice develop liver inflammation and fibrosis. Here we examine if they crosstalk in male mice. We found FOXM1/MAT2A/2B are upregulated after bile duct ligation (BDL) and carbon tetrachloride (CCl4) treatment in hepatocytes, HSCs and Kupffer cells (KCs). FDI-6, a FOXM1 inhibitor, attenuates the development and reverses the progression of CCl4-induced fibrosis while lowering the expression of FOXM1/MAT2A/2B, which exert reciprocal positive regulation on each other transcriptionally. Knocking down any of them lowers HSCs and KCs activation. Deletion of FOXM1 in hepatocytes, HSCs, and KCs protects from BDL-mediated inflammation and fibrosis comparably. Interestingly, HSCs from Foxm1Hep-/-, hepatocytes from Foxm1HSC-/-, and HSCs and hepatocytes from Foxm1KC-/- have lower FOXM1/MAT2A/2B after BDL. This may be partly due to transfer of extracellular vesicles between different cell types. Altogether, FOXM1/MAT2A/MAT2B axis drives liver inflammation and fibrosis.

Mineral quantitative analysis by optical microscope is simple and reliable, and has been widely used in process mineralogy and rock-mineral determination. The line measurement method is fast and efficient, and is suitable for fine-grained mineral particles, which plays an important role in the application. However, the conventional test line has the characteristics of directional identity, and cannot deal with the problem of 'preferential orientation' of the analyzed mineral particles. To solve this problem, a new mineral quantitative method by rotating the platform of an optical microscope was conducted. The main principle is that the length ratio of the circular cutting lines of different mineral particles is equal to their volume ratio. The main test process of the method is as follows:rotating the objective table for a circle and testing the angles (ΔK) that the circular cutting line contained, which is intersected by the mineral particles and the visual field under the microscope. By testing a certain number of visual fields (N) and calculating weight percentage (W), the percent content is acquired by the equation W=[∑ΔK/(N×360)]·(δ/Δ)×100%. After theoretical analysis, the galena, sphalerite, and magnetite thin sections were examined. The results show that the new mineral quantitative method is simple, accurate, and the difference value of the test results is less than ±5% compared with the conventional line measurement method. In addition, this method can be used to effectively solve the negative effect of 'preferential orientation' on the test results.