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Objective To explore the role of indole-3-propionic acid (IPA) in the pathogenesis of metabolic associated fatty liver disease (MAFLD) induced by high-fat diet (HFD) in order to reveal the role and related mechanism of adipose tissue metabolism in the process. Methods A mouse model of MAFLD was induced by HFD. Male C57BL/6J mice (6~7 weeks old) were randomly divided into control group (CON), HFD group, and HFD+IPA intervention group (HFD+IPA). The CON group was fed with control diet, and the HFD group and HFD+IPA group were fed with 60% of high-fat diet. The experiment period was 12 weeks, and IPA was administered at 20 mg/(kg·d) for 6 weeks starting from the 7th week. The body weight and food intake of each group were monitored weekly. After the intervention, the body composition of mice was detected by animal body composition analyzer. After the mice were euthanized, the morphological and structural changes in the liver and adipose tissues were observed by HE staining, the indicators relevant to lipid metabolism in the serum, liver and adipose tissues were detected by automatic blood biochemical analyzer and biochemical kits, and the mRNA expression changes of lipid metabolism and inflammation related genes were detected by qRT-PCR. Results Compared with the CON group, the HFD group had significantly increased body weight and body fat percentage, obvious lipid deposition in the liver, obviously elevated serum alanine aminotransferase, aspartate aminotransferase, liver triglyceride and total cholesterol levels (P < 0.05), and raised mRNA levels of liver fatty acid transporter CD36 (P < 0.05), while IPA intervention significantly reversed the above changes (P < 0.05). IPA intervention significantly inhibited the HFD-induced enlargement of visceral and brown fat cells, reduced the content of visceral adipose tissue (VAT) and serum level of free fatty acids (P < 0.05), and increased the mRNA expression levels of VAT lipolysis (HSL, CGI58), browning genes (Cidea, ND5, UCP1, Prdm16) (P < 0.05), as well as those of brown adipose tissue (BAT) lipolysis (HSL, ATGL) and fatty acid beta oxidation (Cpt1a, PPARα) genes (P < 0.05). Meanwhile, the mRNA levels of TNF-α, IL-1β, CXCL1 and CCL2 in VAT and BAT were decreased after IPA intervention (P < 0.05). Conclusion IPA can improve the occurrence of MAFLD induced by HFD, and its mechanism may be closely associated with its regulation of BAT and VAT morphology, and the mRNA expression of metabolic function and inflammation related genes.

The forming technology of surface micropattern structure was widely used in practical manufacturing as a means to texture the surface of materials and to promote advanced and functional materials. The main methods of surface micropattern forming include hot embossing, chemical etching, electrical discharge machining(EDM), photolithography and 3D printing depending on the application areas of materials. The different surface micropattern structure forming techniques and the basic principles of preparing surface texturise functional materials were reviewed, and their practical applications in photovoltaics, electronic information, intelligent manufacturing, ultra-precision manufacturing and other fields were listed. The characteristics and scope of application of different surface micropattern structure forming technologies are summarized, and the key problems faced in realizing the surface texturisation and functionalization of materials are put forward, which provides certain reference for the micromachining technology of surface micropattern structures.

Objective To study the buccolingual inclination of posterior premolars and molars and the curve of Wilson in patients with different sagittal skeletal patterns, to explore the compensation mechanism of horizontal inclination of posterior teeth in patients with different sagittal skeletal patterns and to provide a reference for the control of posterior tooth inclination in the treatment of bone malocclusion. Methods This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. Ninety CBCT scans of adults and ninety scans of adolescents before orthodontic treatment were evaluated in this cross-sectional study. There were 30 skeletal Class I, Class Ⅱ, and Class Ⅲ patients in the adult group and adolescent group. The inclination angles of posterior teeth and the curve of Wilson of first and second molars were measured, and data were analyzed between adolescents and adults with different sagittal skeletal patterns. Results Compared with skeletal Class Ⅰ adult patients, the upper posterior molar inclination of skeletal Class Ⅱ patients was significantly lower, and the lower posterior molar inclination was significantly higher. Compared with skeletal ClassⅠ adult patients, the upper posterior molar inclination of skeletal Class Ⅲ adult patients was higher, and the lower posterior molar inclination was significantly lower. The Wilson curve of the second molar in skeletal Class Ⅱ adult patients was significantly higher than that in the other groups. Compared with skeletal ClassⅠ adolescent patients, skeletal Class Ⅲ adolescent patients had a significantly higher upper posterior molar inclination; however, no difference was found between the inclination of the posterior teeth between skeletal Class Ⅰ, Class Ⅱ and Class Ⅲ adolescent patients. Comparing adolescent and adult samples, in skeletal Class Ⅱ patients, adults showed more lingual inclination than adolescents in the upper posterior teeth and less lingual inclination in the lower posterior teeth except for the mandibular first molar. Comparing adolescent and adult samples, in skeletal Class Ⅲ patients, adults showed more lingual inclination than adolescents in the lower posterior teeth except for the mandibular second molars and showed no difference in the upper posterior teeth. Conclusions The inclination of the posterior teeth and the curve of Wilson show significant differences between the three sagittal skeletal patterns. Compared with those of skeletal Class Ⅰ patients, the posterior teeth of skeletal Class Ⅱ patients show more lingual inclination in the upper arch and less lingual inclination in the lower arch. Meanwhile, posterior teeth of skeletal Class Ⅲ patients show more lingual inclination in the lower arch and maintain the inclination in the upper arch.

Reef islands are composed of unconsolidated carbonate sediment from the reef that has been organized and deposited on an atoll and platform reef by ocean hydrodynamics. They are frequently found in remote mid-ocean locations within tropical and subtropical waters and are the sole source for habitable land of some island nations. It is anticipated that sea level rise and more frequent and intense storms resulting from global climate change will destabilize these low-lying reef islands, thus there is increasing concern about the persistence and habitability of these islands during future extreme wave events. The reef island morphodynamic response to the action of regular waves has not been reported in the literature. Therefore, this study performed laboratory experiments based on a horizontally one-dimensional reef island physical model in a wave flume. The temporal variation of the island profile under regular waves was measured to analyze the effects of island morphological factors (initial island height and width) and initial island location on its topographic evolution. The results showed that the reef island lost crest elevation and migrated and extended toward its lagoon side under the action of regular waves. Accretion also occurred on the lagoon side beach and random ripples appeared. The time required for the island to reach its equilibrium profile decreased with increasing of initial island height, initial island width, and initial island distance from reef edge. The island crest lowering due to scouring increased with increase of initial island height, but it decreased with increasing of initial island width and initial island distance from the reef edge. Among the three factors, initial island height had the greatest impact on the crest lowering. The island lagoonward migration decreased with increasing of both initial island height and initial island distance from reef edge, but it increased with the increase of initial island width. Among the three factors, initial island location was the most influential factor to lagoonward migration, but no island lagoonward migration was detected when the initial island distance D≥2 m. Regression analysis was used to obtain empirical formulae to predict the island crest lowering and island lagoonward migration, respectively. The outcomes of this study provide a habitability assessment for such low-lying island nations in the context of global climate change.

In the context of new power system construction and the increasingly severe risks of urban security， urban power supply security has now become a top priority of urban security. Firstly， the risks faced by urban power grid in the context of new power system are analyzed. Then， major urban power supply accidents at home and abroad in recent years are sorted out， and the causes of each accident are analyzed. Then， the concept of risk transmission chain is put forward. Based on the evolution and conduction theory of the proposed risk chain， major urban power supply accidents at home and abroad in recent years are deduced， a detailed risk blocking scheme is formulated， and the grid risk assessment process and risk blocking deduction framework are put forward. Finally， the main measures and suggestions for improving the safety level of urban power supply are put forward. The proposed risk transmission chain and risk blocking measures have practical significance for consolidating urban power supply security in building a new power system.

The three-dimensional carbon fiber fabric was densified by chemical vapor infiltration and precursor impregnation cracking composite process, and the high thermal conductivity 3D C/C composite material with density of 1.95 g/cm3 was obtained. Using SEM, XRD, thermal conductivity test, linear expansion coefficient test and three-point bending experiment to study the effect of different heat treatment temperatures of 2350,2550,2850℃ on the microscopic morphology,structure, thermal conductivity, linear expansion coefficient and bending performance of 3D C/C composites. The results show that with the increase of the heat treatment temperature, the mesophase pitch-based carbon fiber graphite sheet structure becomes more obvious, the order of the pyrolytic carbon sheets evenly wrapped around the carbon fiber increases, and the arrangement between the sheets becomes more dense; the graphitization and thermal conductivity of 3D C/C composite materials improve; in the test temperature range of 250-1400℃, the linear expansion coefficient increases slightly with the increase of the test temperature, and the 3D C/C composite after different heat treatment temperatures. The linear expansion coefficient of the materials is -1×10-6-2×10-6℃-1, showing good "zero expansion". In addition, when the heat treatment temperature increases, the bonding of the carbon fiber and the matrix of the 3D C/C composite materials are weakened, resulting in the decrease in the bending strength and flexural modulus of the materials. A large number of long fibers are pulled out on the bending fracture surface of the materials after the high temperature heat treatment at 2850℃. In general, the fracture after three different heat treatment temperatures shows "pseudoplastic" fracture characteristics.

Porous carbon/carbon (C/C) composites prepared by pitch-based carbon fiber and mesophase pitch were densified by chemical vapor infiltration (CVI) and precursor impregnation process (PIP). After different heat temperature treatment (HTT), the unidirectional C/C composites and bidirectional C/C composites were obtained. The microstructure of C/C composites was investigated by SEM, XRD, and the thermal conductivity was analyzed based on the thermal conductivity mechanism. The results show that unidirectional C/C composites and bidirectional C/C composites have dense structures and excellent thermal conductivity along the fiber axis. After 3000 ℃ treatment, the structure of graphite flat layers become more distinct and the graphitization degree is increased by 18.84%, leading to higher thermal conductivity. Furthermore, the thermal conductivity in X direction and Y direction of the bidirectional C/C composites can be calculated from that of unidirectional C/C composites in X direction and Z direction.

In view of problems that fault signal of centrifugal pump is easily submerged by noise and data analysis is difficult, a wear fault analysis method of centrifugal pump impeller based on multi-source signal fusion was proposed. Three vibration signals of volute, outlet and base of centrifugal pump, and electrical signals of prime mover terminal are collected when centrifugal pump impeller is in normal condition and wear state. Wavelet packet decomposition is used to extract characteristic frequency bands of the vibration signals, it is determined that the base can be used as the best detection point by laterally comparing energy values of each frequency band, and frequency analysis range is narrowed by longitudinally comparing the energy values of each frequency band. Based on narrowed frequency analysis range, chirp Z transform is used to analyze electrical signals of prime mover terminal and separate fault characteristics frequency and the third harmonic frequency, so as to extract fault characteristic frequency accurately. Test result verifies effectiveness of the method.

As strategic emerging mineral resources supported by the state, niobium and tantalum are the functional and structural materials needed for the development of emerging industries. Therefore, conducting research on the determination of niobium and tantalum in related materials is of great significance. Unfortunately, niobium and tantalum have similar physical and chemical properties, making it difficult to separate them. However, they are easy to hydrate. Geological samples are difficult to be decomposed, thus the determination of niobium and tantalum has always been a difficult issue. Sample pre-treatment technology and modern analytical techniques are reviewed in this paper. Sample pre-treatment is the key step for niobium and tantalum analysis, therefore a suitable sample digestion and preconcentration method combined with analytical methods and sample characteristics is the premise of accurate determination of niobium and tantalum. Instrument analysis is the mainstream of modern analytical technology. Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) are the most widely used methods for the determination of niobium and tantalum, but it is necessary to solve problems such as coexisting component interference, matrix effects and salt influence. Laser Ablation (LA), X-ray Fluorescence Spectrometry (XRF), and Neutron Activation Analysis (NAA) are the development direction of tantalum and niobium analysis, due to the fact that they avoid the complicated sample pre-treatment and addition of impurities by solid sample introduction.

For the problems of complex failure process and defective failure database for centrifugal pump, an accelerated-life test platform of centrifugal pump based on double circulating lines for isolation measurement was designed. The platform uses sand particle diameter and particle concentration as accelerated life stress factors of centrifugal pump, and selects flow-head curve as evaluation index of its life. The test results show that the platform can accelerate failure process of centrifugal pump, and can implement centrifugal pump characteristic curve fitting and on-line measurement of test data， which satisfies requirement of accelerated life tests.

Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) has been widely used in the determination of Nb and Ta, but its low sensitivity and high detection limits cannot meet the analysis requirement of low content Nb and Ta in ores and metallurgical samples. The sensitizing effect of many organic reagents was optimized in the ICP-AES determination. The results show that ethanol is the best sensitizer for determination of Nb and Ta after the samples were decomposed by open acid-solution with HF-HNO3-H2SO4 mixture. When the concentration of ethanol reaches 6%, the sensitivities of Nb (292.781 nm) and Ta (240.063 nm) have increases of 180.5% and 265.5%, respectively. Moreover, the detection limits of Nb and Ta were reduced from 5.85 to 3.22 μg/g and from 10.65 to 5.03 μg/g, respectively. The recoveries of Nb2O5 and Ta2O5 were 97.7%-101.9% and 96.8%-97.2%, respectively. The precision of this method was less than 6%. The method is suitable for the simultaneous determination of low and high contents of Nb and Ta, and is particularly suitable for determining Nb and Ta in ore concentrates, medium ores and the tailings of metallurgical samples from the same batch, which overcomes the bad agreement of recovery between ICP-AES and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).

At present, research on crane hoisting system are generally done in way of electrical system and in way of mechanical system, or done in way of simple link of electrical system and mechanical system, so it's difficult to establish an effective and precise mathematical model. For the problem, an electromechanical coupling mathematical model of crane hoisting system was built based on analyzing of relationships between all component parts of hoisting system of crane. The model avoids to neglect interrelationship between the electrical system model and mechanical system model through introducing electromagnetism torque and elastic coefficient of ropes as variables. Meanwhile, a simulation test was performed for the model with speed regulation method based on vector control and taking position of load movement as control variable. The simulation result showed that the model preferably reflectes work process of hoisting system of crane.

Relationship of all parts of crane hoisting system was analyzed and mathematic model of the system was established, so as to effectively unify moving states of motor and loads of the system. A controller of load position of crane hoisting system based on adaptive Backstepping strategy was designed on the basis of the model, which takes load position as a control variable. The simulation result showed that the controller not only has faster responding speed and smaller tracking error, but also restrains influence of load wave and parameter perturbation effectively with good robustness.

In view of problem of fracture of cylinder in strength test and type test for column cylinder, the paper put forward a scheme of crack monitoring of column cylinder based on acoustic emission technology. The scheme uses acoustic emission technology to capture, analyze, process and display elastic wave of crack produced in compression process of column, uses time difference location method to get position of acoustic emission source, and uses wavelet packet technology to process acoustic emission signal to improve location precision. The test result showed that it is feasible to use acoustic emission technology to produce and development and make risk analysis of crack and weld of column cylinder.

To investigate the impact of climate change on the growth period and yield of irrigated spring maize in arid region of Northwest China, the study was conducted based on located observational experiment and climatic data from 1984 to 2022. The results showed that the temperature increased significantly during the entire growth period with a climate trend rate of 0.76°C•10y-1 (P<0.01), and a significant rise in active accumulated temperature above 10°C, with a climate trend rate of 135.80°C•d•10y-1 (P<0.01). Although there was no significant change in precipitation during the entire growth period, it increased significantly during the milky-maturity stage, with a climate trend rate of 4.50mm•10y-1 (P<0.05). The sunshine duration increased significantly from 1984 to 2004, with a climate trend rate of 126.88h•10y-1 (P<0.01), but decreased significantly in the last 19 years, with a climate trend rate of -109.38h•10y-1 (P<0.01). The growth days of spring maize increased from 1984 to 2004, with a climatic trend rate of 9.86d•10y-1 (P<0.01), but decreased significantly in the last 19 years, with a climatic trend rate of 7.39d•10y-1 . The length of sowing-seedling and seventh leaf-jointing was significantly negatively correlated with temperature, respectively. The length of sowing-seeding, third leaf-seventh leaf and silking-milky was significantly positively correlated (P<0.05) with precipitation, respectively. The length of different growth periods was significantly positively correlated (P<0.01) with sunshine duration, respectively. The yield of spring maize fluctuated and climatic yield was significantly negatively correlated (P<0.05) with precipitation. In summary, climate change has been unfavorable to spring maize growth under current irrigation methods in arid region of northwest China. [ABSTRACT FROM AUTHOR]

Objective To provide reference for controlling or delaying the decline of pulmonary ventilation function in male pneumoconiosis patients by studying associations of serum albumin levels with the risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients. Methods A retrospective cohort design was adopted in this study. Male pneumoconiosis patients who were hospitalized in West China Fourth Hospital from January 2012 to December 2021 and did not have pulmonary ventilation dysfunction at baseline were selected as the study objects. Cox proportional hazard regression models were used to calculate HRs and 95% CIs to evaluate the association of baseline serum albumin levels and the risk of severe or very severe pulmonary ventilation dysfunction. Restricted cubic spline plot was used to explore whether there was a dose-response relationship between baseline serum albumin concentrations and the risk of severe or very severe pulmonary ventilation dysfunction. Results A total of 746 subjects were included in this study. Fully adjusted model results of Cox proportional hazard regression analysis showed that male pneumoconiosis patients with serum albumin higher than 40.8 g/L had a reduced risk of severe or very severe pulmonary ventilation dysfunction compared with male pneumoconiosis patients with serum albumin lower than 34.4g/L (HR = 0.660, 95% CI: 0.439-0.992). The restricted cubic spline figure showed that the risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients gradually decreased with the gradual increase of serum albumin concentrations and there was a linear negative relationship between baseline serum albumin concentrations and the incidence risk of severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients (P < 0.05). Conclusion Higher serum albumin is a protective factor for severe or very severe pulmonary ventilation dysfunction in male pneumoconiosis patients and maintaining the serum albumin concentrations above 40.8 g/L can reduce the risk of severe or very severe pulmonary ventilation dysfunction. [ABSTRACT FROM AUTHOR]

Objective To construct a deep learning model based on multi -task learning to assist clinicians in differential diagnosis and staging of pneumoconiosis. Methods The digital chest radiographs of 3 600 patients from an occupational disease hospital in Sichuan Province from 2011 to 2022 were collected, and the full convolution neural network (UNet) was used to segment the lung field. Based on multi-task learning, the multi-task model was constructed using the correlation between tasks. The multi -task model was pre -trained on the ChestX -ray14 dataset, whose backbone network was DenseNetl21, and two classifiers were added behind the backbone network. Paired t-test was used to compare the differences in accuracy, precision, sensitivity, and Fl scores between single-task model and multi-task model. Results The test set results showed that the differential diagnosis and diagnostic staging performance of the single-task model was about 90% and 77%, respectively. The differential diagnosis and diagnosis staging performance of the multi-task model was about 94% and 86%, which was higher than that of the single-task model about 4% and 9%, respectively. The difference between the evaluation indexes was statistically significant (P < 0.05). Conclusion The multi-task model has more advantages than the single-task model and can effectively realize the differential diagnosis and accurate staging of pneumoconiosis and pulmonary tuberculosis. [ABSTRACT FROM AUTHOR]

In order to reveal the synergistic effect of biological and engineering measures on improving saline-alkali soil, and to clarify the suitable buried spacing and organic-inorganic fertilizer application ratio for sunflower production in coastal agricultural areas, this paper designs three different hidden pipe spacing of 10 m (S1), 15 m (S2), and 20 m (S3), as well as six fertilization treatments of 100% organic fertilizer (100% OF), 75% organic fertilizer+25% inorganic fertilizer (75% OF), 50% organic fertilizer+50% inorganic fertilizer (50% OF), 25% organic fertilizer+75% inorganic fertilizer (25% OF), 100% inorganic fertilizer (0% OF) and no fertilization (CK). The response of sunflower yield, quality, nitrogen utilization, and soil available nutrients, organic matter, and total salt content is observed. The results show that under the same distance between tubes, the 25% OF fertilization treatment has the most significant yield increase effect, while under the same fertilization treatment, the S2 spacing is at a higher level in sunflower yield. Under different treatments, the 25% of fertilization treatment has the highest sunflower yield under S2 condition, reaching 3.82 t/hm2. Increasing the proportion of organic fertilizer application is beneficial for increasing the content of crude fat, oleic acid, and linoleic acid in sunflower seeds. Fertilization treatment significantly increases the nitrogen uptake amount of sunflower plants, with an increase of 18.1-47.2%, 8.6-40.5%, and 8.8-34.5% under S1, S2, and S3 spacing compared with CK treatment, respectively. The nitrogen utilization efficiency of sunflowers shows a trend of first increasing and then decreasing with the increase in organic fertilizer proportion, S2-25% OF and S1-25% OF treatments at a higher level, reaching 44.2% and 43.9%, respectively. The content of available nitrogen, available phosphorus, and available potassium in soil is positively correlated with the proportion of organic fertilizer application. Under S1-S3 spacing, the content of available nitrogen, available phosphorus, and available potassium in organic fertilizer treatment is on average 22.0%, 2.4%, and 26.4% higher than CK. The smaller the distance between hidden pipes and the higher the proportion of organic fertilizer application will lead to the higher the salt reduction rate of the topsoil. The salt reduction rate of the 100% of treatment under S1 spacing has reached 42.6%. Considering the factors such as yield, quality, and nitrogen fertilizer utilization efficiency, this paper recommends using a 25% organic fertilizer application ratio under 15 m dark tube spacing as the optimal plan for sunflower production in saline alkali soil. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Taipinglinchang Formation is the key oil-gas exploration horizon in Sunwu-Jiayin Basin. Based on the detailed field observation and description, the sedimentology of section of Taipinglinchang Formation in the east of the basin is studied in this paper. The results show that the sedimentary facies developed in Taipinglinchang Formation include lacustrine facies and fan delta facies, which can be further divided into 3 sedimentary subfacies with 6 sedimentary microfacies. The petrology and organic geochemical characteristics of the shale in Taipinglinchang Formation are analyzed by various organic geochemical testing methods. The results indicate that the mineral composition of shale is mainly quartz, belonging to felsic shale. The maceral composition is dominated by sapropelinite, with oil-prone property. The source rocks are of medium-good quality, with the organic matter types of II1-II2, which are in the low mature-mature stage, suggesting a good hydrocarbon potential. The results may provide basic data for further research and oil-gas exploration in the basin. [ABSTRACT FROM AUTHOR]

Purposes The flexible bedding layer and pile cap have great influences on the pile-soil stress ratio, load sharing ratio, and settlement of CFG pile composite foundation, and further research is still needed about how the flexible bedding layer and pile cap jointly affect the characteristics of the composite foundation in field tests. Methods By using a section of CFG pile composite foundation with soft foundation treatment as the engineering background, field in-situ tests were conducted for the combinations of bedding thicknesses of 100, 200 and 300 mm and pile cap size of 0.8, 1.0, and 1.2 m under the control of constant number of geogrid layers to investigate the pile-soil stress ratio, load sharing ratio, and settlement characteristics of CFG pile composite foundation. Findings Field tests show that with the increase of cushion thickness from 100 to 300 mm, pile-soil load ratio decreases by 51.5%, pile-soil stress ratio decreases by 52.5%, and total settlement increases by 7.9%. As the diameter of pile cap increases from 0.8 to 1.2 m, the pile-soil load ratio increases by 29.0%, the pile-soil stress ratio decreases by 29.2%, and the total settlement is 10.4%. For the regional geological conditions in this work, it is advisable to choose the CFG pile composite foundation with cushion thickness of 100 mm and pile cap diameter of 1.2 m.

Objective At present, a relatively systematic, mature and rapid excavation construction method for the connection passage construction in hard rock stratum has not been formed yet. Due to the small cross-section and limited operating space in the connection passage, construction with the conventional construction method is less efficient with significant construction risks. Therefore, it is necessary to conduct in-depth study on the technology of controlled blasting in the connection passage of metro shield section in hard rock stratum. Method Taking the connection passage in a shield section of Fuzhou Metro Line 4 as a case study, the controlled blasting technology suitable for this project is proposed. According to the engineering characteristics of the project, the calculating parameters required by the maximum single blast charge for a single-section are set up. In addition, based on the distance between the designed connection passage and the objects to be protected, three levels of maximum single-section charges are calculated, and the schemes for blasting hole design, charge structure design and charge blockage are proposed. Six ground settlement measuring points are selected on the ground above the connection passage, and the settlement curves of the six points during construction are obtained to analyze the influence of blasting on ground settlement. Result & Conclusion The measures of reserving protection layers, treating rock masses as rock walls, shallow hole differential blasting, and digital micro-difference initiation being taken in the process of construction, effectively reduce the explosion impact and blasting vibration, achieving the preset goal of safe blasting and rapid excavation.

Praseodymium (Pr) is a critical mineral for the global clean energy industry. The global demand for Pr continues to increase. China possesses the largest proven reserves and highest production of Pr worldwide. However, a future Pr supply-demand gap still could occur in China. Developing a circular economy and promoting material recycling are considered solutions to the potential supply constraints. This study adopts a material flow analysis method and combines it with the recycling input rate (RIR) indicator to estimate the potential quantities of the Pr recycling supply in China from 2011 to 2020. The key findings are as follows: (1) From 2011 to 2020, 7.902 × 104 t Pr entered the anthropogenic cycle system in China from the supply side, of which 1.639 × 104 t Pr originated from recycling; (2) 1.369 × 104 t Pr was recycled from NdFeB magnet production scraps, with the RIR remaining stable at approximately 17%; (3) theoretically, 2.7 × 103 t Pr could be recycled from end-of-life (EoL) products, and the RIR of EoL products could increase from 0.04% to 5.17%. In view of the major challenges in realizing Pr recycling from EoL products, this study proposes improvement strategies to promote Pr recycling in China. They include improving the extended producer responsibility of China, progressively establishing consumer responsibility for relevant products, and guiding the industry to formulate recycling-related technical specifications and industry standards.

Objective To investigate the causal association between 91 kinds of circulating inflammatory proteins and different subtypes of breast cancer (estrogen receptor-positive and -negative breast cancer) using a two-sample Mendelian randomization (MR) method. Methods Corresponding exposure and outcome data were extracted from the genome-wide association study database. The data were analyzed by two-sample MR with inverse-variance weighting (IVW) as the primary study method, and MR-Egger, weighted median, simple mode, and weighted mode were used to complement the results. The results were complemented by sensitivity analysis to verify the reliability of the data. Results The IVW results showed that SULT1A1 (P=0.0007) was associated with an increased risk of total BC, whereas IL-5 (P=0.0011) was associated with a decreased risk of total BC. SULT1A1 (P=0.0011) and CX3CL1 (P=0.0005) were associated with an increased risk of ER+BC, whereas beta-NGF (P=0.0001) was associated with an increased risk of ER−BC. Supplementary analysis methods validated that the findings were consistent in direction and magnitude. The results of the sensitivity analysis showed that the data were reliable and unbiased. Conclusion Using the MR method, this study confirms that SULT1A1 is a risk factor for overall breast cancer, whereas IL-5 is a protective factor for overall breast cancer. SULT1A1 and CX3CL1 are risk factors for estrogen receptor-positive breast cancer, and beta-NGF is a risk factor for estrogen receptor-negative breast cancer.

C/C-HfC composites with a density of 2.14 g/cm3 was successfully prepared using an inorganic hafnium solution as a precursor via chemical vapor infiltration (CVI) and precursor infiltration pyrolysis (PIP) methods, and its microstructure and composition were analyzed. The results show that the HfC ceramics are uniformly dispersed in the pores of the matrix and closely bonded to the matrix. The material's ablation resistance is significantly enhanced by introducing HfC ceramics. Under the same heat flux conditions, when the ablation time is 120 s, the linear and mass ablation rates of the C/C-HfC composite are 6.20×10-2 mm·s-1 and 2.03×10-2 g·s-1, respectively, which are reduced by 48.33% and 40.12%, respectively, compared to those of the C/C composite. During the ablation process, HfC would react with oxygen in the heat flux to generate molten HfO2, which uniformly covers the surface of the matrix to form a protective layer, isolates the heat flux, prevents oxidation of the matrix, and prevents heat transfer. The evaporation of molten HfO2 also takes away some of the surface's heat. With the increase of ablation time, the loss of HfO2 will gradually increase, the protective layer on the surface of the matrix will be gradually destroyed, and the ablation damage of the heat flux on the matrix would become more severe.

In order to solve the problem of low precision in drum height adjustment caused by different working conditions during the working process of the shearer, a generation method for cutting height template of the shearer drums based on working condition triggering is proposed. The method preprocesses and extracts features from historical sensor data of the shearer, selects 5-dimensional feature data that affect the adjustment of drum height, including cutting motor current, cutting motor temperature, pitch angle, roll angle, and traction speed. The method constructs a compensated echo state network (C-ESN) model for generating drum cutting height templates. The method establishes a working condition triggering mechanism, inputs real-time data from the shearer sensors into the C-ESN model. The method uses testing error as the judgment criterion to recognize the current working condition of the shearer as normal area, triangular coal area, or abnormal working condition. Finally, the C-ESN model generates the corresponding drum cutting height template. When the testing errors in both the triangular coal area and the normal area are greater than the threshold, transfer learning method is used to correct the parameters of the cutting height template with small testing errors to ensure the precision of the cutting height template under abnormal working conditions. The experimental results based on actual data of on-site coal mining machines show that compared with the actual cutting height, the maximum errors of the left and right drum cutting height templates in the normal area are 11.47 cm and 9.96 cm, respectively, and in the triangular coal area are 12.91 cm and 7.94 cm, respectively.The results can meet the practical requirements of engineering. Compared with traditional echo state network and radial basis function network models, the precision of the C-ESN model has been improved by 54% and 57% in the normal region, and by 10% and 69% in the triangular coal region, respectively.

Objective: To Prepared of β-Cyclodextrin inclusion complex with Foeniculum vulgare（fennel） volatile ooil and study on its sstructural characterization and stability. Methods: Based on the inclusion rate, the inclusion yield and the content of trans-anethole in the inclusion compound, the comprehensive evaluation index was established, and the effects of the ratio of fennel volatile oil to β-cyclodextrin, inclusion temperature and inclusion time on it were explored. The preparation process was optimized by orthogonal test. It was characterized by scanning electron microscopy, thin layer chromatography, Fourier infrared spectroscopy and differential scanning calorimetry. Finally, the stability of the inclusion compound was investigated by light, high temperature and high humidity tests. Results: The optimum conditions obtained by saturated aqueous solution method were as follows: the ratio of volatile oil to β-cyclodextrin was 1∶8 (mL/g), the inclusion temperature was 40 ℃, the inclusion time was 60 min. Under these conditions, the inclusion rate of fennel volatile oil inclusion compound was 96.90%, the inclusion yield was 93. 61%, the content of trans-anethole was 6.81%, and the comprehensive score was 99.68. The inclusion compound was white powder with loose texture and good inclusion effect. The inclusion compound was characterized by scanning electron microscopy, thin layer chromatography, Fourier infrared spectroscopy and differential scanning calorimetry. Its stability was good within 5 days of illumination (4 000 lx), volatile components in the inclusion compound were easy to lose at high temperature (60 ℃) for a long time, and it would deliquesce and agglomerate when the relative humidity was more than 75%. Under the conditions of long illumination time, high temperature and high humidity, the inclusion rate and trans-anethole content were obviously reduced. Conclusion: The inclusion rate and inclusion yield of the above-mentioned optimal inclusion process are high, and the process is stable. When stored in a dry and sealed environment at room temperature, the β-cyclodextrin inclusion compound of fennel volatile oil has certain stability compared with the volatile oil.

The existing deep reinforced learning algorithms cannot see local environments and have insufficient perceptual information on UAV autonomous navigation tasks. The paper investigates the UAV's autonomous navigation tasks in its unknown environments based on the nondeterministic policy soft actor-critic (SAC) reinforced learning model. Specifically, the paper proposes a policy network based on a memory enhancement mechanism, which integrates the historical memory information processing with current observations to extract the temporal dependency of the statements so as to enhance the state estimation ability under locally observable conditions and avoid the learning algorithm from falling into a locally optimal solution. In addition, a non-sparse reward function is designed to reduce the challenge of the reinforced learning strategy to converge under sparse reward conditions. Finally, several complex scenarios are trained and validated in the Airsim+UE4 simulation platform. The experimental results show that the proposed method has a navigation success rate 10% higher than that of the benchmark algorithm and that the average flight distance is 21% shorter, which effectively enhances the stability and convergence of the UAV autonomous navigation algorithm.

Objective: This study focused on the antioxidant synergistic mechanism between resveratrol and sesamol. Methods: The levels of free radicals and peroxide free radicals in sunflower seed oil were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide assays, respectively. The proportion of resveratrol and sesamol were optimized by integrating the measurements with the determination of the induction period. Additionally, quantum chemical simulations were employed to elucidate the underlying reaction processes. Results: Upon heating sunflower seed oil supplemented with resveratrol and sesamol at 180 ℃ for 2 hours, the total content of free radicals was determined as （0.08±0.03） mol/L and （0.20±0.03） mol/L, respectively, in comparison to （0.44±0.01） mol/L in the control sample. Resveratrol exhibited the highest inhibitory efficiency, while sesamol has the strongest scavenging ability of peroxide radicals. The optimal concentrations for their synergistic effect in purified sunflower seed oil were determined as 1 400, 200 mg/kg, and resveratrol had protective effect on sesamol at the degradation rate of 180 ℃. Conclusion: By utilizing quantum chemical methods, it was found that a dynamic equilibrium process exists between the two compounds. As the amount of resveratrol added is seven times that of sesamol, and the reaction is more inclined to supply hydrogen to sesamol radicals by resveratrol.

Background Difficult problems such as poor diagnosis and treatment capacity of diabetes in the community, low screening rate of complications, low standardized monitoring rate of blood glucose, and low rate of blood glucose compliance are the problems that general practitioners need to think about and solve when carrying out management of diabetes patients. It is necessary to explore and innovate the standardized management mode of diabetes in the community for making general practitioners become specialists in the general practice and achieve "precision management combining general care and specialty care". Objective To understand the management effect of diabetes "1358 model" on community diabetes patients based on "precision management combining general care and specialty care". Methods A total of 212 patients with diabetes who visited the outpatient clinic at the Hongkou District North Bund Street Community Health Service Center from May to July 2020 and had signed a contract with the community general practitioner were selected as the research subjects and divided into 106 cases in the control group and 106 cases in the intervention group by the random number table method. The patients in the control group received routine follow-up management, and the patients in the intervention group received the "1358 model" of diabetes based on "precision management combining general care and specialty care". One year after the intervention, the cognitive and behavioral levels of diabetes, the attainment of key indicators and the experience of visiting community health centers were compared between the two groups. Results There was no statistically significant difference in the cognition and behavior related to diabetes management and the attainment rate of key indicators between the two groups (P>0.05). After intervention, the proportions of patients in the intervention group who monitored FPG within 1 month, monitored 2 hPG within 1 month, carried out comprehensive blood glucose monitoring within 1 month, monitored HbA1c within 6 months, carried out self-monitoring of blood glucose, recorded a blood glucose diary, standardized the use of medication, followed the doctor's advice on diet, screened for peripheral vascular complications within 1 year, screened for urinary albumin/creatinine within 1 year, screened for carotid artery plaques within 1 year, screened for the inner ocular fundus within 1 year were higher than those of the control group, and the difference was statistically significant (P0.05). After the intervention, the rates of FPG attainment, HbA1c attainment and ABC composite attainment of patients in the intervention group was higher than those of the control group, and the difference was statistically significant (P

Panicle nitrogen fertilizer amount and shading during grain filling period directly and obviously regulated the relationship between carbon and nitrogen metabolism of rice grains by affecting leaf photosynthesis and plant nitrogen nutrition, which would be benefit to forming different characteristics of rice quality. In order to investigate the combined effect between panicle nitrogen fertilizer amount and shading during grain filling period on quality of conventional japonica rice, field experiments were carried out with three panicle nitrogen application treatments of 40.5 kg hm-2 (N1), 81.0 kg hm-2 (N2) and 121.5 kg hm-2 (N3) at the same amount of basal and tilling fertilizers, and two artificial shading treatments of 100% natural light (S0) and 50% natural light (S50) during grain filling period in 2019 and 2020. The quality characteristics of conventional japonica rice Huaidao 5, Nanjing 9108, and Yangnongxiang 28 were determined under different light and nitrogen conditions during grain filling period. Results showed that with the increase of panicle nitrogen fertilizer amount, the brown rice rate, milled rice rate, and heading rice rate firstly increased and then decreased under S0 and decreased under S50. The brown rice rate, milled rice rate and heading rice rate of S0 were significantly higher than S50, while the processing quality of S0N2 with higher heading rice rate was the best among all treatments. The chalkiness grain percentage and chalkiness degree of rice had a trend of S50N3 > S50N2 > S50N1 > S0N3 > S0N2 > S0N1. Therefore, the increase of panicle nitrogen fertilizer amount and the shading during grain filling period had a cumulative effect on the increase of chalkiness grain rate and chalkiness degree of rice. Both the increase of panicle nitrogen fertilizer amount and shading during grain filling period decreased the amylose content and gel consistency, but increased the protein content. And the variation coefficient of glutelin was higher than other protein components among treatments. The rice taste value was decreased with the increase of panicle nitrogen fertilizer amount and the shading during grain filling period, while the direct influence of taste characteristic value on taste value was different among rice varieties. The peak viscosity and breakdown viscosity of rice starch decreased with the increase of panicle nitrogen fertilizer amount and the shading during grain filling period, while the setback viscosity increased. And the combination of light and nitrogen increased the difference of the above viscosity indexes among treatments. Based on the ratio of amylose content to protein content under different treatments of panicle nitrogen fertilizer amount and shading during grain filling period, the carbon and nitrogen metabolism ability of plants at grain filling stage were changed. In addition, the amylose content and protein content were significantly negatively correlated with taste value, while the correlation coefficient of protein was bigger than amylose content. Thus, an appropriate reduction of panicle nitrogen application fertilizer amount was beneficial to the improvement of rice processing quality, appearance quality and cooking and eating quality at grain filling stage with shading. The reduction of amylose content and especially the reduction of protein content might be an effective way to improve rice taste. The results would provide scientific support for the innovation of high yield and good taste rice cultivation techniques. [ABSTRACT FROM AUTHOR]

The development characteristics of sedimentary microfacies significantly affect the occurrence and exploitation of shale oil. Taking the cores from the upper part of 4th Member of Quantou Formation and lower part of 2nd-3rd members of Qingshankou Formation from SYY1 and SYY2 wells in Qijia-Gulong area of northern Songliao Basin as the research object, the paper studies the sedimentary microfacies through large-scale core observation and fine description based on core lithology, bedding structures, fossils, inclusions and electrical characteristics. It is concluded that lacustrine facies deposits are mainly developed in the cores of SYY1 and SYY2 wells, which can be divided into two sedimentary subfacies of shallow lake and semi-deep-deep lake, with five sedimentary microfacies including beach-bar sands in shallow lake, ostracoda beach, argillaceous shallow lake, semi-deep-deep lake mud and oil shale. The lower part of 1st Member of Qingshankou Formation is dominated by semi-deep-deep lake subfacies; while the upper part of 1st Member and lower part of 2nd-3rd members of Qingshankou Formation and upper part of 4th Member of Quantou Formation, by shallow lake subfacies. The latter three microfacies are all favorable to form shale oil. [ABSTRACT FROM AUTHOR]

Objective: A method for the determination of 7 synthetic colorants in freshly prepared beverages by high performance liquid chromatography dual （HPLC） wavelength method with automatic solid phase extraction was established. Methods: Extraction conditions: The sample was extracted 2 times with pure water, and then the supernatant combined after centrifugation. The pH of the supernatant was adjusted to 3~4. After activation by an automatic solid-phase extraction device, loading, rinsing, and elution of the sample were carried out on the Poly-sery synthetic colorant solid-phase extraction column. The eluent was concentrated to 200 μL by nitrogen blowing, and then fixed to 1.0 mL with 50% mobile phase A+50% mobile phase B. Instrument conditions: The column was C18 column. The mobile phase was 20 mmol/L ammonium acetate-methanol, gradient elution. The flow rate was 1.0 mL/min. The injection volume was 10 μL. The detection wavelength were 254 nm and 628 nm. Results: The correlation coefficient of each substance in the range of 0.5～50 μg/mL was greater than 0.999 9, the detection limit of the method was 0.023～0.179 mg/kg, the quantitative limit was 0.078～0.598 mg/kg, the standard recovery was 92.4%～96.8%, and the relative standard deviation （RSD） was 1.2%～4.2%. Conclusion: This method has low consumption of toxic reagents, simple operation steps, high degree of automation, good recovery and repeatability, and it is suitable for the determination of large quantities of samples.

As a novel type of refractory material, ceramizable-silicon-rubber composite has broad application potential in the wire and cable industry. To improve the mechanical strength and flame retardancy of materials, three halogen-free flame-retardant ceramizable-silicone-rubber insulation materials with different compositions suitable for radiation-crosslinking process were constructed by using methyl vinyl silicone rubber (MVSR) as the matrix. It was found that the mechanical strength and moduli of ceramicable-silicone-rubber composites could be greatly improved after 60Co (γ-ray) radiation crosslinking. Among them, Composite-3 with allyl-functionalized cyclotriphosphazene (CP-Allyl) and Mg(OH)2 as synergistic flame retardant exhibited the better radiation crosslinking effect and flame retardancy. The tensile strength of Composite-3 treated by a dose of 80 kGy could reach 4.65 MPa, and its limiting oxygen index was 34.4%. In addition, these composites could form dense and hard ceramic layers after high-temperature ablation at 700-1 000 ℃. As a result, the radiation-crosslinked silicone-rubber composites with a good performance and a high-temperature ceramic forming ability are expected to be applied in the field of insulation materials for wires and cables.

In order to improve the transmission capability by exploring the relationship between torsional stiffness on output shaft and load meshing characteristics, a simulation model of finite element analysis (FEA) is built to evaluate the performance of tooth profile under transmission loading. A triple-circular-arc tooth profile of flexspline is constructed, and the radial modification of the tooth profile is adjusted to minimize the outer envelope overlap of meshing motion of the tooth profiles. Then, a triple-circular-arc planar tooth profile of circular splines is designed with the envelop method according to the outer envelope. A triple-circular-arc tooth profile of flexspline with tradial modification is constructed in several cross sections, and the spatial tooth profiles of flexsplines are generated by axial lofting in finite element environment. A finite element simulation model including circular spline with planar tooth profile, cup-shaped flexspline with spatial tooth profile and outer ring of wave generators is established. Transmission torques of different amplitudes in two rotational directions are applied on the flange plate at the bottom of the flexspline engaged with a fixed circular spline, and the meshing force distribution and torsional stiffness hysteresis curves are simulated. The number of meshing teeth in different meshing states can be estimated with the relationship between torsional stiffness and meshing characteristics of tooth profiles. The simulation results show that the number of meshing teeth is positively correlated with the torsional stiffness. Using the measureable hysteresis curve of torsional stiffness, the immeasurable meshing characteristics such as the number of meshing teeth can be estimated.

Patient and public versions of guidelines (PVG) have attracted increasing attention in China, and their number is also on the rise. This article explores the methods for the development of PVG, introduces and compares different development methods, and incorporates case studies for interpretation, with the aim of providing reference for the developers of PVG and further promoting the development of PVG in China.

Objective In this study, a meta-analysis of the expression of G-protein-coupled estrogen receptor (GPER) in breast cancer (BC) and its role in prognosis was conducted to understand the effect of this expression on the survival and clinicopathological characteristics of patients with BC. Methods Identical search strategies were used to search relevant literature in electronic databases updated to November 24, 2022. Individual hazard ratios (HRs) and odds ratios (ORs) with their 95%CI were extracted and pooled to evaluate the strength of the association between positive GPER expression and survival results, the clinicopathological features of patients with BC. Begg's tests, Egger's tests, and funnel plots were used to evaluate publication bias. Heterogeneity and sensitivity were also assessed. All works were completed using Review Manager 5.4.1. Results GPER expression had a favorable effect on OS (HR=0.77; 95%CI: 0.49-1.22; Z=01.10; P=0.27) and an unfavorable effect on DFS/RFS/DDFS (HR=1.03; 95%CI: 0.64-1.65; Z=00.13; P=0.90) in patients with BC. GPER expression was not significantly related to the prognosis of patients with BC, and GPER expression was not an independent prognostic factor. Furthermore, GPER expression was significantly associated with TNM staging (OR=0.31, 95%CI: 0.06-0.55, Z=02.43, P=0.02), distant metastasis (OR=6.82, 95%CI: 1.89-24.55, Z=02.94, P=0.003), histological grade (OR=0.009, 95%CI: −0.16-0.01, Z=02.16, P=0.03), ER expression (OR=1.77, 95%CI: 1.15-2.72, Z=02.59, P=0.009), and PR expression (OR=1.36, 95%CI: 1.00-1.84, Z=01.95, P=0.05). Conclusion GPER may not be an independent prognostic factor for BC. GPER expression was significantly related to some clinicopathological features of patients with BC, including TNM staging, distant metastasis, histological grade, ER expression, and PR expression.

Objective·To explore microRNAs (miRNAs) as biomarkers of polycystic ovary syndrome (PCOS) and the biological significance in the pathogenesis of PCOS. Methods·Five patients with PCOS from January 2019 to October 2019 in Renji Hospital, Shanghai Jiao Tong University School of Medicine were selected as the observation group, and 5 healthy women were selected as the control group. Granulosa cells from 2 groups were collected and RNA was extracted by TRIzol method. TruSeq Small RNA Library Prep Kit was used to construct miRNA-Seq library. After the quality inspection of the library, NextSeq500 was used for high-throughput sequencing. Bioinformatics data analysis was performed on the sequencing results. RT-qPCR was used to verify the differential expression of candidate miRNA markers. Results·We finally got 20 differentially expressed miRNAs (all P<0.05). Among them, miR-196a-5p, miR-10a-5p and miR-451a were significantly up-regulated, while miR-877-5p and miR-2355-5p were significantly down-regulated. These differentially expressed miRNAs and their target genes may be involved in the transcriptional regulation mechanism of PCOS occurrence and development. Conclusion·Differentially expressed miRNAs have potential as PCOS biomarkers and are involved in the occurrence and development of PCOS. [ABSTRACT FROM AUTHOR]

The waveguide invariant is usually not extracted from the striation pattern of broadband continuous spectrum in the low frequency analysis and recording spectrum at low signal-to-noise ratio. In this paper, the correlation coefficient of multi-tonal acoustic intensity interference fluctuation is utilized to estimate waveguide invariant. Since the proportional relationship between the reference intensity interference fluctuation and the scaled intensity interference fluctuation is dependent on waveguide invariant, the waveguide invariant estimation can be done. Firstly, the tonal intensity interference fluctuation has been resampled in the new time domain under the radial and non-radial motion models respectively. Then, the similarity degree between the resampling reference tonal intensity interference fluctuation and the scaling tonal intensity interference fluctuation can be described by correlation coefficient, and the peak of correlation coefficient is corresponding to the true value. Finally, the numerical results and the experimental results prove the proposed method's effectiveness.

There are abundant shale oil resources in the first member of Qingshankou Formation in Qijia and Gulong sags of Songliao Basin. In the past, the shale oil resources were calculated mainly based on incomplete old core data with corrected pyrolysis Si or chloroform asphalt A as oil-bearing parameters. The accuracy of corrected parameters was affected by multiple factors including sample freshness, testing means and correction method, leading to certain limitations in the application of the above parameters. According to the latest development in shale oil exploration, the paper compares the applications of different oil-bearing parameters (pyrolysis S1; chloroform bitumen "A" and oil saturation) in shale oil resource calculation. The result shows that oil saturation can reflect the content of free oil and dissolved hydrocarbon, without considering the influence of adsorbed oil and correction of light hydrocarbon, heavy hydrocarbon and NSO compound. This parameter is more suitable for the calculation of shale oil resources under the condition of fresh sample test data. The plane distribution of effective shale thickness, TOC, organic maturity (Ro) and burial depth are determined on the basis of latest drilling results and test data of shale oil parameter well. The shale oil enrichment areas in the first member of Qingshankou Formation in Qijiahe and Gulong sags are 1957.23 km² and 4509.09 km² respectively by multifactor overlap method. Combined with the measured data of oil saturation, density and effective porosity logging interpretation data of sealed frozen samples, the resources of shale oil enriched areas in Qijia and Gulong sags are calculated as 19.79x108 and 27.29x108 respectively, indicating the matrix shale oil in the study area has a good exploration prospect. [ABSTRACT FROM AUTHOR]

The shale oil resources are abundant in the first member of Qingshankou Formation, Upper Cretaceous, in northern Songliao Basin. The previous exploration was targeted at shale fractures and interbedded thin sands and ostracod layers. Due to the limitation of distribution range of target layers, the shale oil exploration results have not been satisfactory. Focusing on the widely-developed shale reservoirs in the basin, the survey refreshes the geological understanding of shale oil in the shale reservoirs of continental basin, and forms the exploration technology system. The industrial oil flows of SYY1, SYY2 and SYY3 wells pumped after fracturing yield 3.22, 4.93 and 3.46 m³/d respectively, the flowing high-yield industrial oil run of 14.37 m³/d from SYY-1HF well and pumping oil run of 10.06 m³/d from SYY-2HF well after fracturing, achieving a major breakthrough in the strategic survey of shale oil in northern Songliao Basin. [ABSTRACT FROM AUTHOR]

Taking the shale from the first member of Qingshankou Formation in SYY-3 well of Sanzhao sag in Songliao Basin as an example, the paper studies the petrological characteristics, including sedimentary structure, organic matter abundance and mineral composition. The results show that the shale develops massive structure and laminated structure are, with TOC of 0.50%-6.82% (averagely 3.16%) and S1+S2 of 2.01x10-3-49.41x10-3 (averagely 23.02x10-3), generally belonging to good-best source rock. The mineral composition is mainly felsic mineral, followed by clay, with low content of carbonate and pyrite. Based on the petrological characteristics, the first member of Qingshankou Formation can be divided into 9 types of lithofacies by the classification criteria of organic matter abundance-sedimentary structure-mineral composition, among which the laminated felsic shale with high TOC has good hydrocarbon generation potential, serving as the most favorable lithofacies for shale oil exploration in Sanzhao sag. [ABSTRACT FROM AUTHOR]

Shale oil exploration in China has entered a new field. As shale oil reservoir is much more complex than conventional reservoir, the improvement of imaging accuracy of shale oil reservoir is the key to shale oil seismic exploration. The wide-azimuth 3D seismic technique is widely used in seismic exploration currently as it can solve relatively difficult geological problems while providing high-quality seismic data. Taking the study area Y88 in Qijia-Gulong depression of Songliao Basin as an example, the paper conducts shale oil reservoir processing by wide-azimuth data, and analyzes the characteristics of wave field, signal-to-noise ratio and frequency. On this basis, the processing flow of wide-azimuth data is determined and the wide-azimuth and broadband high-resolution amplitude-preserving processing technique is adopted for better imaging. [ABSTRACT FROM AUTHOR]

Objective To evaluate the methodological quality of systematic review/meta analysis (SR/MA) published in Chinese Science Citation Database (CSCD) journals in 2020, with the aim of providing suggestions for researchers in China to develop SR/MA and reference for editors and reviewers to review SR/MA. Methods The list of journals was formed with a sample of journals published by the Chinese Medical Association Publishing House and included in CSCD. Four researchers working in pairs conducted independently manual searches on the official websites of the journals to include SR/MA published in 2020, and one researcher conducted a supplementary search on China National Knowledge Infrastructure. After identifying the included literature, the researchers worked in pairs to extract information independently, evaluated methodological quality by using AMSTAR 2(A Measurement Tool to Assess Systematic Reviews 2) and performed statistical analysis of the results. Results A total of 79 journals from the Chinese Medical Association Publishing House were included in CSCD, 46 of which published SR/MA in 2020, and 126 SR/MA were included for analysis after screening according to inclusion and exclusion criteria. AMSTAR 2 evaluation results showed that the average score of SR/MA was 10.38±1.91. The scored proportion of 9 items was more than 70%. SR/MA met partially/met a minimum of 5 AMSTAR 2 items and a maximum of 12 items. Before the key items were adjusted, over 90% of SR/MA's credibility rating was critically low. After adjusting the key items according to the actual Chinese situation, about 40% of SR/MA's credibility rating was medium and low, respectively. The results of the stratified analysis showed that the use of GRADE, adherence to the PRISMA statement, the number of authors greater than 5, the language of publication, the type of included studies including RCTs, and the reporting of funding were not factors that influenced the methodological quality of SR/MA. Conclusions The methodological quality of SR/MA published in CSCD journals in 2020 need to improve. Attention should be paid to the registration, retrieval, inclusion and exclusion criteria of SR/MA as well as financial support, so as to effectively improve the quality of SR/MA.

The geological circle has been studying the South China Ocean for 40 years. Based on the existing studies, the geological features of the middle Neogene South China Ocean and related geological structures and mineralization issues have been further understood through the topics of Regional Geology of China: Jiangxi, Mineral Geology of China: Jiangxi, and Evolution and Mineralization in South China Ocean–Marginal Pacific. The Pingxiang–Shexian–Suzhou junction zone connects the Jinsha River–Red River junction zone to the north of Henei, which is the subduction zone of the South China Ocean in the middle Neogene. It formed the boundary between the Yangtse plate and the newly-defined China-Southeast Asia plate (referred to as the Jinsha River–Red River–Shexian–Suzhou junction zone), which is now a latitudinal tectonic belt bending southward. The South China Ocean is a Meso-Neoproterozoic ocean between the Yangzi Paleo-plate and the Cathaysia-Southeast Asia Paleo-plate, closed at about 820± Ma. The Jinning movement took place during the collision of the plates, resulting in a consolidation of the Yangtze Block and the Cathaysia-Southeast Asia Block, where they united into one. The region has been an essential part of the Eurasian plate since the Indo-Chinese period, and the South China Rift System had been formed from 815± Ma in the late Neogene to the early Paleozoic. The Tethys and Paleo-Pacific tectonic domains have formed the geological tectonic framework of southern China and plateaus, continents, seas, and island arcs of the neighboring areas since the late Paleozoic. The subduction zone of the South China Ocean has evolved into the “Jinsha River–Hong River–Qinzhou Bay–-Hangzhou Bay” mega metallogenic belt of tungsten-tin-copper-gold polymetallic precious and rare metals, featuring two major magmatic mineralization series of S and I types.

Carbon/carbon-polyimide composites were prepared by chemical vapor infiltration and vacuum-pressure impregnation curing process. Firstly, the carbon felt was deposited with pyrolytic carbon by chemical vapor infiltration method to prepare porous carbon/carbon materials with pyrolytic carbon contents of 7.33%(mass fraction, the same below), 14.55% and 22.00%, respectively. Then, through a specific impregnation curing process, the carbon/carbon-polyimide composites P1, P2 and P3 and the control group P0 without pyrolytic carbon were obtained in turn. Through SEM, linear expansion coefficient test and mechanical properties test, the effects of different pyrolytic carbon contents on the microstructure, average linear expansion coefficient and mechanical properties of carbon/carbon-polyimide composites were investigated. The results show that in the temperature range of 20-300℃, the XY-direction average linear expansion coefficients of P0, P1, P2 and P3 are between (0.67-0.79)×10-6℃-1, and the XY-direction average linear expansion coefficients of four groups are basically the same. The Z-direction average linear expansion coefficients of P1, P2 and P3 decrease by 41.6%, 41.8% and 24.1%, respectively compared with P0. Pyrolytic carbon significantly reduces the Z-direction average linear expansion coefficient of materials. The XY-direction compressive strengths of P0, P1, P2 and P3 are 243.91, 244.73, 216.65 MPa and 210.79 MPa, respectively, and the Z-direction compressive strengths are 269.22, 258.80, 246.68 MPa and 219.20 MPa, respectively. The compressive strength of P1 is equivalent to that of P0. The Z-direction bending strengths of P0, P1, P2 and P3 are 92.77, 77.11, 80.71 MPa and 86.06 MPa, respectively. Different pyrolytic carbon contents have different effects on the mechanical properties of materials. The lower pyrolytic carbon content can basically maintain compressive strength of materials, while the higher pyrolytic carbon content can basically maintain bending strength of materials.

The current theory considers that the shape of the deformed flexspline tooth ring neutral line is an isometric line of the cam, which ignores the effect of fit clearance and neutral line's elongation. To reveal the mechanical properties and the tooth positioning on deformed flexspline tooth rings with fit clearance, taking elliptical cam wave generator as an example and considering the fit clearance caused by the clearance between the inner wall of flexsplines, the outer surface of wave generators, the clearance of flexible bearings and the elongation of neutral lines, a contact mechanical model of tooth rings is established. The wrap angle after deformation is introduced as an unknown parameter, and the internal forces in tooth rings in the wrap angle is determined according to the curvature of the neutral line of tooth rings represented by the elliptic equidistant line and the equilibrium equations of the forces. The size of non-contact area, and the internal forces and deformation of tooth ring is solved iteratively with Energy Method according to the displacement conditions on minor axis and the curvature condition at wrap angle and arc length relationship. Based on the results of finite element model, the theoretical results and tooth positions are compared and verified. Both the theoretical analysis and the numerical simulation show that the actual wrap angle of zero clearance fit is far less than 90°, and the full round fitting cam is not true because of the elongation of the neutral line. Reducing fit clearance can effectively increase the contact area and reduce the radial load and the wear of flexible bearings. Considering the wrap angle and the circumferential elongation, more accurate tooth positioning may lead to a more accurate foundation for structural design and meshing analysis of harmonic gears.

Objective: Spirulina platensis, Neochloris oleoabundans, Phaeodactylum tricornutum and Isochrysis zhanjiangensis are common microalgae for food and feed. Their odors can affect the flavor of foods made from the aquaculture and farm animals through the food-chain transfer. This study aimed at analyzing the flavor characteristics of these four microalgae to provide fundamental data for the further researches of the relative foods. Methods: HS-SPME-GC-MS and electronic nose techniques were applied to identify the volatile compounds and the flavor profiles of the microalgae were analyzed thereafter. Results: In the four microalgae mentioned above, 33, 35, 23 and 29 volatile compounds were identified respectively. The results showed that hexanol, 1-octen-3-ol, (E,Z)-2,4-decadienal, (E)-2-nonenal and hexanal were the main compounds in S. platensis contributing to its grassy, earthy and fatty odor; (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, octanal, 1-octen-3-ol, hexanal and hexanol were the key volatile compounds in N. oleoabundans and gave it a flavor feature of fatty, earthy, fishy and grassy note; heptanal, naphthalene, octanal, hexanal and 1-octen-3-ol were the main volatile compounds in P. tricornutum contributing to its fatty odor; (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, 1-octen-3-ol, hexanol, hexanal and (E,E)-2,4-heptadienal were the primary volatile substances in I. zhanjiangensis giving it fatty, grassy and fishy odor. Conclusion: Hexanal, hexanol, 1-octen-3-ol and olefin/diolefin aldehyde with 7~10 carbon atoms are the main odorous compounds in the four microalgae, contributing to their grassy, earthy, fishy and fatty odorous feature.

Objects: The object of this paper was to determine the taxonomic status of a newly isolated of thermophilic microalga, and to study the stability of its phycocyanin to evaluate its possibility of application in food. Methods: The newly isolated algal strain was morphologically observed by optical microscope, and identified its taxonomic status based on its 16S rDNA sequence and the phylogenetic tree analysis. The phycocyanin of the alga was obtained by ultrasound-assisted extraction, and the stability of phycocyanin was investigated and evaluated based on the changes of the optical density measured with spectrophotometer under different levels of temperature, illumination and pH. Results: The alga cell was rod shape, straight or arc sometimes, binary fission, and was a branch of genus Thermosynechococcus. A crude extract of phycocyanin with a purity of 0.941 and a color value of 196.53 was obtained from the alga, and the yield was 11.37% (for dry mass weight). The stability tests showed that the phycocyanin was stable for 3.5 h at the temperature 60 ℃, its optical density retained 91.4% after illumination of 6000 lux for 7 d, the color was stable kept pH4.0~8.0 for 3.5 h, but it exhibited a poor stability in strong acid or strong alkali. Conclusion: The isolated microalga is a strain of the genus Thermosynechococcus. Its phycocyanin has good thermal-stability, photo-stability and acid-base-stability, exhibiting encouraging possibility for food application.