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Objective Shale generally contains water, and it is highly important to clarify the occurrence characteristics of adsorbed water in shale to improve the drainage effect of shale gas. Methods This study analysed shale cores from the JY11-4 and JY41-5 wells in the Jiaoshiba area of Fuling. The influence of high-pressure conditions on the occurrence characteristics of adsorbed water in shale was investigated using custom-designed frozen nitrogen adsorption experiments and nuclear magnetic resonance experiments. Results and Conclusion The results show that (1) under atmospheric pressure, the average volume of adsorbed water per unit mass calculated by the "weighing method" is 0.017 3 mL/g. The volume proportion of water in the micropores and mesopores (average of 90.94%) significantly exceeds that in the macropores (average of 9.06%). This may be because water molecules cannot occupy the adsorption sites in all the shale pores when the relative pressure is relatively low. Most water molecules condense in micropores and mesoporous pores, and only a few water molecules enter the macropores. In addition, the small and medium pores in clay-rich shale become "filled and blocked" by water molecules in the process of water adsorption. (2) Under a saturated water pressure of 30 MPa, the average adsorbed water volume per unit mass of the sample calculated by the "weighing method" is 0.021 6 mL/g. The volume proportions of water in the micropores and mesopores (average of 40.26%) is lower than that in macropores (average of 59.74%), which may be related to the fact that water molecules can occupy more adsorption sites on the inner surface of micropores and mesoporous pores under the action of capillary forces when the relative pressure is significantly increased. (3) Compared with normal pressure, high-pressure conditions increase the volume of water adsorbed per unit mass of shale (approximately 25% increase in the experiment), and the proportion of water volume in large pores is greater than that in micropores and mesoporous pores. (4) During hydraulic fracturing, the relative pressure of the reservoir increases significantly. Under the action of capillary forces, fracturing fluid may enter large pores that cannot enter under the pressure of the original reservoir to "relieve" the "unsaturated state" of the original shale reservoir. After fracturing is completed, the pressure around the reservoir is gradually released, and the fracturing fluid that originally enters the adsorption pores of the shale may have difficulty overcoming the capillary resistance at the pore, making it difficult to return.

Considering the dual requirements of stability and low carbon, integrating clean coal power with carbon capture, utilization and storage (CCUS) and combining new energy power generation with energy storage have become the inevitable trends of China’s power industry. This study investigates the typical cases regarding clean coal power, CCUS, new energy power generation, and energy storage in China and abroad, analyzing the trend of technological development. A levelling cost model is used to measure the economical efficiency and changes of “clean coal power + CCUS” in three stages: current stage, technological breakthroughs, and commercial application. The competitiveness of “clean coal power + CCUS” is evaluated by comparing it with the “new energy + energy storage” mode from three dimensions: economical efficiency, stability, and security. The results indicate that technological breakthroughs and commercialization of CCUS will reduce the cost of “clean coal power + CCUS” by 30.3%−77.6%. When the cost of CCUS is lower than 550 CNY/t CO2, “clean coal power + CCUS” is more competitive than the “new energy + energy storage” mode. When the cost of CCUS is lower than 150 CNY/t CO2, the cost of “clean coal power + CCUS” will be lower than that of “new energy + energy storage”. Moreover, advantageous technical routes and application scenarios of “clean coal power + CCUS” are calculated and analyzed based on the competitiveness and synergy of “clean coal power + CCUS” and “new energy + energy storage”. The breakthrough directions and technical path of zero-carbon clean coal power are proposed from the aspects of improving the complementarity of clean coal power, enhancing the competitiveness of “clean coal power + CCUS”, and promoting the optimal combination of coal power and new energy. Furthermore, the following suggestions are proposed to promote the development of lowcarbon clean coal: (1) clarifying the preferential technology route, (2) strengthening the research and development of transformative and disruptive technologies, (3) improving the peak shaving capability of clean coal-fired power units, (4) promoting the coupling and coordinated development of coal-fired power and new energy, and (5) establishing a high-end composite talent support system.

Accurate determination of the inverse kinematics for the drilling arm of a drilling and anchoring robot is crucial in achieving automatic support in coal mine roadways. Addressing issues such as poor accuracy, limited real-time performance, and susceptibility to local optima, this study presents a novel approach for solving the inverse kinematics problem of an unconventional mechanical arm by combining Monte Carlo random sampling method and Newton iteration method. Initially, a kinematics model is established based on the structure of the drilling arm, and individual coordinate systems are defined for each joint to enable forward kinematics solutions. The Monte Carlo method is employed to determine the motion space of the drill boom. By subdividing the motion space into smaller cubes with a defined step size, a mapping relationship is established between the spatial coordinates of these cubes and the corresponding joint variable values. Using the transformation matrix associated with a given target space point, an index function is employed to identify the relevant small cubes. The points within these cubes, which are closest to the target space point, are calculated, and their corresponding joint variable values are used as initial values. The Newton iteration method is then introduced, utilizing the iterative formula for multivariate functions to determine the variation of each joint variable. The inverse kinematics solution for the unconventional manipulator is obtained through iterative cycles. The simulation results show that, compared with Newton-Raphson iterative method based on random initial values and the particle swarm optimization algorithm, the corresponding average angle error of the calculation results of this method is reduced by 64.98% and 57.34%, and the average time consumption is reduced by 35.90% and 22.33%, respectively, thereby enhancing solution accuracy and real-time performance. The feasibility and effectiveness of the proposed Monte Carlo and Newton iteration method for solving the inverse kinematics problem in unconventional manipulators are verified. Overall, this research provides evidence supporting the practicality and efficiency of the proposed Monte Carlo random sampling method and Newton iteration method for accurate inverse kinematics solutions in unconventional manipulators.

ObjectiveTo evaluate the internal exposure level of antibiotics in children and analyze its influencing factors.MethodsQuestionnaires were disseminated and urine samples were collected in June 2022 from kindergarteners and children enrolled in primary schools in a city in Jiangsu Province. The presence of 41 antibiotics was detected in urine using ultra-performance liquid chromatography and tandem mass spectrometry. Chi-square tests and rank-sum tests were performed to test the detection frequencies and concentrations of urinary antibiotics. Logistic regression models were established to identify the independent variables associated with the detection frequencies and concentrations of urinary antibiotics.ResultsA total of 295 children aged 3-8 from Jiangsu Province were included in this study. The detection frequencies of the antibiotics ranged from 0 to 48.1%， with sulfameter （48.1%） having the highest frequency， followed by sulfadiazine （38.3%） and erythromycin （38.3%）. The 95th percentile concentrations of the antibiotics ranged from 0 to 23.7 ng/mL， with amoxicillin （23.7 ng/mL） having the highest concentration， followed by azithromycin （6.3 ng/mL） and sulfadiazine （3.5 ng/mL）. The results of Logistic regression analysis showed that age， residence， source of drinking water， and freshwater fish and shrimp consumption frequency were identified as independent influencing factors for specific antibiotic exposure.ConclusionDifferent antibiotics were detected in the urine of children in Jiangsu Province. Intervention measures should be adopted to reduce the exposure of children to antibiotics associated with high detection frequencies and concentrations.

[Objective] Metal hydride hydrogen storage reactors serve as core components in solid-state hydrogen storage techniques.During the reversible hydrogen absorption and desorption reactions of metal hydrides, significant heat exchange occurs, leading to uneven temperature distribution within the reactors and resulting in adverse effects on the hydrogen storage performance and service life of the reactors. Therefore, effective thermal management is recognized as one of the key technologies to improve the efficiency and stability of metal hydride hydrogen storage reactors. [Methods] This paper aims to review the research progress in the field of thermal management for metal hydride hydrogen storage reactors both in China and abroad. To this end, an extensive investigation of available literature was conducted to summarize the principle of hydrogen absorption-desorption reactions in metal hydrides. The heat transfer process within hydrogen storage reactors was examined, leading to the division of the heat exchange process into three stages: heat transfer in the hydrogen storage materials; heat exchange between the hydrogen storage materials and the wall surface of the hydrogen storage reactors; heat exchange between the wall surface of the hydrogen storage reactors and the ambient environment. Furthermore, thermal management methods that enhance heat exchange efficiency in each stage were categorized. [Results] Through an analysis of the heat exchange performance in various thermal management methods, this review presents an overview of the research progress in these approaches, including the use of heat exchange tubes, fins, and phase-change materials. The evaluation of hydrogen absorption and desorption rates as crucial metrics allows for a comparison of their advantages and disadvantages. Additionally, the review summarizes the existing challenges in this field and envisions the prospects for future trends in thermal management for metal hydride hydrogen storage reactors. [Conclusion] Different thermal management methods have their pros and cons. Therefore, it is essential to select and optimize specific thermal management methods based on the scale and intentions of metal hydride hydrogen storage reactors, to design efficient and compact thermal management systems. The outcomes of this research lay a foundation for the large-scale and engineering applications of solid-state hydrogen storage techniques.

Porosity is a key parameter that affects the heat and moisture transfer within a grain pile. In order to investigate the distribution law of porosity in bulk grain piles in grain silos, grain compression experiment was carried out to obtain the porosity of different grain types under different moisture content and vertical pressure conditions. A porosity prediction model for grain cell based on GWO-BP neural network was proposed, and the model was compared with the porosity prediction results of BP neural network model and random forest model. Finally, the generalization ability of the model was verified using the grain cell box test. The results showed that the porosity prediction performance of the GWO-BP neural network model was the best, and the evaluation indexes of the model, including R2 of 0.960 5, RMSE of 0.013 7 and MAE of 0.013 1, were all within the permissible range. This study has provided a neural network prediction method for the determination of grain porosity, which could provide an important foundation for in-depth multi-field coupling analysis of grain piles and theoretical support for safe grain storage.

As intelligent technologies and unmanned systems develop rapidly, the concept of cross-domain cooperative technology of intelligent unmanned swarm systems has emerged, received widespread attention, and gradually become the high ground in the competition of unmanned system technologies among countries worldwide. Based on the development demand for the cross-domain cooperative technology of intelligent unmanned swarm systems in China, this study summarizes the research status of the crossdomain cooperative technology in typical unmanned scenarios such as sea – air, air – ground, and sea – ground/sea – ground – air, and thoroughly analyzes the current status, technological demand, and key research directions of the technology. Additionally, countermeasures and suggestions are proposed to promote the steady and rapid development of the cross-domain cooperative technology from the perspectives of overall concept, system architecture, theoretical innovation, and technological breakthroughs, with the aim of facilitating the sustained development of unmanned systems in China.

The construction of China’s ecological civilization has entered a critical period in which carbon reduction is the key strategic direction since the “dual carbon” goal was proposed. Coal’s status as the least expensive energy source will be unchanged in the short term. CH4-CO2 coordinated emission reduction is the core of the convert from “dual control” of energy consumption to “dual control” of total carbon emissions and intensity. On the basis of accurately analyzing the challenges of CH4-CO2 dual carbon emission reduction in coal mines at the stage of carbon peak and carbon neutrality, the development of coal and gas co-mining technology in the dual carbon strategy has been clarified to be combined with the core principles of current demand-technical research-policy drive, the development path of coal and gas co-mining technology in the dual carbon strategy is formulated, and the key technical issues are discussed. At the peak stage of carbon emission, CH4 emission reduction is based on the perspective of emission source control. The core is the key technology for carbon emission reduction in the whole cycle of gas extraction and utilization, including the targeted and accurate extraction technology in gas-rich areas, the permeability-enhancement, replacement and flow-increasement extraction by injecting gas in low-permeability coal seams, the gas escape channel plugging and carbon reduction technology in closed mines, and the integrated technology of gas enrichment-concentration-utilization. The purpose is to greatly improve the efficiency of high-concentration gas extraction and utilization and to reduce the carbon emission from low-concentration and ventilated gas. CO2 emission reduction is centered on the “CCUS + ecological carbon sink” region-wide negative carbon emission technology to further absorb flue gas and pure CO2 emissions, including CO2 storage in coal seams, industrial solid waste goaf filling synergistic CO2 geological storage, soil-surface-atmosphere anomaly monitoring and ecological carbon sink technology in coal mine carbon storage areas, etc. The core task of the carbon neutralization stage is to achieve CH4-CO2 (near) zero carbon emission. CO2 emission reduction should be transformed from a technical research demonstration project to a large-scale application stage, and establishing an intelligent monitoring and dynamic control technology system for CH4-CO2 emission from coal mine in the whole life cycle to realize the in-deep matching between monitoring and control technology means and carbon emission links, and the in-deep docking between the monitoring-control cloud platform of carbon emission and the global monitoring-control system of coal mines. Finally, the insights and thoughts is put forward on the green and low-carbon development of the future coal and gas co-mining system. ① Continue to deepen the coal mine CH4 zero emission technology model of “efficient and accurate extraction + full-concentration cascade utilization”. ② Continue to tackle the CO2 zero emission technology system of “CO2 engineering storage + ecological carbon sinks”. ③ Actively exploring the comprehensive solution of “zero carbon wisdom park” in coal mines, and forming a policy support system for carbon emission reduction in coal mines that emphasizes both incentive and pushback.

Coal is vital for the energy system of China. As the digital economy develops rapidly in China and in the context of carbon peaking and carbon neutrality, promoting the digital development of the coal industry becomes crucial for the industrial upgrade and high-quality development of the industry. This study defines the digitalization of the coal industry, clarifies the digital economy in the coal industry, and for the first time calculates the scale of digital economy in China's coal industry. The basic conditions for the digital development of the coal industry are sorted out, and the urgent issues that constrain the digital development of the industry, such as concept understanding, infrastructure, talent teams, and core technologies, are summarized. On this basis, strategic goals are proposed, and a strategic path is elucidated from the aspects of digital infrastructure, skilled personnel, key capabilities, and development environment. The key development directions, technologies for the entire industry chain, and key technologies for the digital development of the coal industry are emphasized. Furthermore, the following policy recommendations are proposed to build a solid support for the digital development of the coal industry: (1) establishing data management institutions and platforms, (2) establishing laboratories for developing coal-related digital technologies, (3) enhancing the data sharing and value mining capabilities of the industry, and (4) building training bases to cultivate skilled personnel for the digital development of the coal industry.

Lightning activity poses threats to human life and property safety. A large volume studies indicate that aerosol plays a significant role in lightning activity. To explore the effect of different types of aerosols on lightning activity in the Yangtze River Delta and its surrounding areas, cloud-to-ground (CG) lightning location data and aerosol optical depth from reanalysis dataset is analyzed in the target area(27.5°-35°N, 115°-122.5°E) during 2015-2021.The spatial distribution of aerosol optical depth (AOD) with CG lightning condition and without CG lightning condition, and monthly variation of aerosol concentration under two conditions are investigated. All the grids in the target region show that sulfate AOD is higher, while dust AOD is lower with CG lightning. In summer there are little differences between the AOD with CG lightning and without CG lightning conditions. In other months, more sulfate aerosol and less dust aerosol are found with CG lightning condition.The spatial distribution of CG lightning density difference under higher and lower AOD conditions is given. The results show that when the sulfate AOD is high, the CG lightning density of most grids is higher. The CG lightning density is significantly lower when the dust AOD is high.The correlation coefficient between CG lightning density and the AOD for different types of aerosols is calculated for the months when CG lightning is active. When the concentration of sulfate aerosol is low, the correlation coefficient between sulfate AOD and CG lightning density is significant. When the sulfate aerosol concentration exceeds a certain threshold, there is no significant correlation between CG lightning density and sulfate AOD. The positive correlation may be due to the fact that the cloud microphysical effect of sulfate aerosols can promote the development of convection. With sufficient water vapors, sulfate aerosols form cloud condensation nuclei and promote CG lightning activity. When the concentration of sulfate aerosols is higher than the threshold value, the cloud microphysical effect and the radiation effect of aerosol may be counterbalanced, which may lead to weak correlation between CG lightning density and aerosol concentration. The results also show a weak negative correlation between dust aerosol and CG lightning density in April, May, June, and no significant correlation in July, August, September. Considering the low concentration of dust aerosols in the Yangtze River Delta and its surrounding areas, the inhibitory effect of dust aerosols on CG lightning activity may not be just explained by the radiation effect. The large particle size of dust aerosol may play a significant role in suppressing CG lightning activity.

To solve the problems of line overload tripping and cascading faults caused by power flow transfer in power systems， an optimal control strategy for grid overload considering energy storage and electrothermal characteristics of transmission lines is proposed. Firstly， the variation of electrothermal characteristics of transmission lines is analyzed. Based on meteorological data from various observation stations covered by transmission corridors in practical power grids， a method for calculating conductor temperatures considering meteorological distribution is formulated to enhance the accuracy of estimating line overload capacity. Furthermore， to minimize the control cost， an optimized control model incorporating energy storage for power system overload is established. The simulated annealing particle swarm optimization algorithm is used to solve the model， swiftly determining the optimal control and adjustment quantities and thereby fully leveraging the energy storage regulation capability and line overload tolerance capacity to effectively prevent cascading faults in the power grid. Finally， the effectiveness of the proposed control method is validated using the improved IEEE 39-node system.

ObjectiveTo evaluate the surgical effects of transumbilical laparoendoscopic single-site surgery (TU-LESS） through self-made approach channel versus traditional porous laparoscopic surgery(TPLS） in the patients with benign gynecological diseases(BGD). MethodsA total of 100 BGD patients admitted to Tangshan Union Medical College Hospital from January 2021 to May 2022 were retrospectively selected and divided into control group(receiving TPLS, n=50） and research group(receiving self-made approach channel TU-LESS, n=50). The following indicators were compared between two groups, including operation time, intraoperative bleeding volume, postoperative anal exhaust time, intraoperative and postoperative complications, postoperative VAS score at 24hours, the time to get out of bed after surgery, hospital stay and treatment costs. ResultsCompared with control group, postoperative VAS score and treatment cost significantly decreased, and the postoperative anal exhaust time, postoperative off-bed time and hospitalization time were significantly shortened in research group(P＜0.05). The intraoperative bleeding volume was below 120mL in both groups, but the amount of bleeding in research group was statistically more than that in control group (P＜0.05). There was no significant difference in the operation time and the incidence of postoperative complications between control group and research group(P>0.05). ConclusionIn the treatment of patients with benign gynecological diseases, the clinical application effect of self-made approach TU-LESS is definite and can effectively reduce the economic cost, improve postoperative recovery of patients.

Using the cloud top data provided by Fengyun-4A (FY-4A) multi-channel scanning imaging radiometer (AGRI) and lightning observations provided by the ground-based global lightning positioning network (WWLLN) during 2019-2020, combined with the meteorological and oceanographic data from MICAPS and extreme wind data recorded by buoys, the spatial-temporal distribution and convective activity characteristics of 71 thunderstorm and strong wind processes in the South China Sea are studied. Results show that the thunderstorms and strong winds recorded by the observatory are mainly distributed in the northern part of the South China Sea. Thunderstorms and strong winds mainly occur from May to September, with the peak in August and valley in March. Thunderstorms and strong winds mainly occur in the morning (0700-1200 BT), with the highest frequency at 1000 BT, a sharp decrease in the frequency in the afternoon, and the lowest frequency between 2100 BT and 2300 BT. The maximum value area of lightning density is distributed in the offshore area of southern Guangdong, and the lightning concentration occurs in the radius of 40 km to 80 km of the observation station. There is an obvious lightning jump in the isolated thunderstorms and strong winds process, and the occurrence time of the first jump is 30 min to 2 min ahead of the peak time of the wind, showing that the lightning activity is indicative of the peak of thunderstorms and strong winds. In terms of convection characteristics, at the peak moment of thunderstorms and wind speed, the cloud top brightness temperature at the location of the observation station is concentrated at 200-220 K, and the cloud top height is concentrated at 12.5 km to 15 km. The distance between the lowest brightness temperature value of isolated thunderstorms and strong winds cloud cluster (i.e., the location of the strongest convection) and the strong winds observation site (i.e., the location of the thunderstorms and strong winds) is 77.2 km on average, and the average difference of brightness temperature value is 2.6 K.

Tea is beneficial to human health, which is rich in tea pigments with important biological activities. Theabrownin, derived from theaflavins and thearubigins by oxidative polymerization, mainly distributes in semi-fermented oolong tea, and completely fermented black tea and dark tea. As a kind of macromolecular substance, theabrownin cannot be directly absorbed by the gut, but it can directly interact with intestinal microbiota to regulate and maintain the homeostasis of intestinal flora. Theabrownin has multiple physiological roles via modulating the gut microbiota, including inhibiting hepatic cholesterol production, promoting the catabolism of cholesterol and triglyceride, and promoting energy metabolism in adipose tissues, thereby improving lipid metabolism. Theabrownin can also directly influence the gut absorption of glucose to improve carbohydrate metabolism and maintain blood glucose homeostasis. Theabrownin plays an anti-tumor role by inducing apoptosis and regulating gene expression in tumor cells. Theabrownin also plays an anti-inflammatory role via participating in the regulation of the immune cell differentiation and the levels of inflammatory factors. This review summarizes the formation process, the extraction procedures, and the chemical structure of theabrownin, and reviews the effects and mechanisms of theabrownin on intestinal microbiota, lipid metabolism, blood glucose homeostasis, cancer and inflammation.

Objective To investigate the nursing dependence level and discharge readiness of middle-aged and elderly patients undergoing coronary artery bypass grafting, and to explore the correlation between them. Methods A questionnaire survey by using Readiness for Hospital Discharge Scale(RHDS) and Care Dependency Scale (CDS) was conducted between February 2021 and August 2022 among 130 coronary artery bypass grafting patients who were scheduled to be discharged from hospital. Results The total score of CDS in middle-aged and elderly patients undergoing coronary artery bypass grafting was (54. 86(+-)4. 38), and the total score of RHDS was (169. 64(+-)16. 32). Pearson correlation analysis showed that the score of CDS in middle-aged and elderly patients undergoing coronary artery bypass grafting was positively correlated with the score of RHDS. Conclusion Age and medical payment ratio were the main factors affecting the degree of nursing dependence of patients. Medical staff should focus on the elderly patients and the patients with heavy family medical burden payment ratio. To develop targeted discharge planning services to reduce patients' nursing dependence. (目的 了解中老年冠状动脉旁路移植术患者护理依赖水平和出院准备度现状, 并探讨两者间的相关性。方法 于2021年2月—2022年8月对130例拟计划出院的冠状动脉旁路移植术患者进行问卷调查。结果 中老年冠状动脉旁路移植术患者护理依赖总分为(54. 86(+-)4. 38)分, 出院准备度总分为(169. 64(+-)16. 32)分, Pearson相关分析显示: 中老年冠状动脉旁路移植术患者护理依赖量表(CDS)得分与出院准备度量表(RHDS)得分呈显著正相关关系。结论 年龄和医疗支付比例是患者护理依赖严重程度的独立影响因素, 建议医护人员应重点关注高龄和家庭医疗负担支付比例较重的患者群体, 制定针对性的出院计划服务进而降低患者护理依赖水平。)

ObjectiveSaposhnikovia divaricata (Turcz.) Schischk is a kind of traditional Chinese medicine. Currently, the methods of identifying the origin and quality of Saposhnikovia divaricata (Turcz.) Schischk are mainly based on their physical or chemical characteristics, which is impossible to make an accurate measurement of Groundness identification. With the continuous development of deep learning, its advantages of no manual extraction and high classification accuracy are widely used in different fields, and an attention-embedded ShuffleNet V2-based model was proposed in this study to address the problems of large computation and low accuracy of most convolutional neural network models in the identification of Chinese herbal medicine Saposhnikovia divaricata (Turcz.) Schischk.MethodsThe model architecture was adjusted to reduce the number of model parameters and computation without degrading the network performance, and the traditional residual network was replaced by the Hourglass residual network, while the SE attention mechanism was introduced to embed the hourglass residual network with additional channel attention into ShuffleNet V2. The important features were enhanced and the unimportant features were weakened by controlling the size of the channel ratio to make the extracted features more directional by SE attention. The SiLU activation function was used to replace the ReLU activation function to enhance the generalization ability of the model Enriching local feature learning. Therefore, a lightweight Shuffle-Hourglass SE model was proposed. The samples of Saposhnikovia divaricata (Turcz.) Schischk used in this research were samples from the main production areas, including more than 1000 samples from five production areas in Heilongjiang, Jilin, Hebei, Gansu and Inner Mongolia. A total of 5234 images of Saposhnikovia divaricata (Turcz.) Schischk were obtained by using cell phone photography indoors under white daylight, fully taking into account the geographical distribution differences of different Saposhnikovia divaricata (Turcz.) Schischk. The data set of Saposhnikovia divaricata (Turcz.) Schischk images was expanded to 10,120 by using random flip, random crop, brightness and contrast enhancement processes. In order to verify the effectiveness of the model proposed, four classical network models, VGG16, MobileNet V2, ShuffleNet V2 and SqueezeNet V2, were selected for comparison experiments, ECA ( Efficient Channel Attention ) attention mechanism, CBAM ( Convolutional Block Attention Module ) attention mechanism and CA attention mechanism were chosen to compare with SE. All attention mechanisms were introduced into the same position in the ShuffleNet V2 model, and ReLU, H-swish and ELU activation functions were selected for contrast experiments under the condition in which other parameters unchanged. In order to explore the performance improvement of ShuffleNet V2 model by using the attention mechanism of SE module, Hourglass residual block and activation function, Shuffle-Hourglass SE model ablation experiment was carried out. Finally, loss, accuracy, precision, recall and F1 score in test set and training set were used as evaluation indexes of model performances.Results and DiscussionsThe results showed that the Shuffle-Hourglass SE model proposed achieved the best performances. An accuracy of 95.32%, recall of 95.28%, and F1 score of 95.27% were obtained in the test set, which was 2.09%, 2.1 %, and 2.19 % higher than the ShuffleNet V2 model, respectively. The test duration and model size were 246.34 ms and 3.23 M, respectively, which were not only optimal among Traditional CNN such as VGG and Desnet,but had great advantages among lightweight networks such as MobileNet V2、SqueezeNet V2 and ShufffleNet V2. Compared with the classical convolutional network VGG, 7.41% of the accuracy was improved, 71.89% of the test duration was reduced, and 96.76% of the model size was reduced by the Shuffle-Hourglass SE model proposed in this study. Although the test duration of ShuffleNet V2 and MobileNet V2 were similar, the accuracy and speed of the Shuffle-Hourglass SE model improved, which proved its better performance. Compared with MobileNet V2, the test duration was reduced by 69.31 ms, the model size was reduced by 1.98 M, and the accuracy was increased by 10.5 %. In terms of classification accuracy, the improved network maintains higher recognition accuracy and better classification performance.ConclusionsThe model proposed in this research is able to identify the Saposhnikovia divaricata (Turcz.) Schischk originality well while maintaining high identification accuracy and consuming less storage space, which is helpful for realizing real-time identification of Saposhnikovia divaricata (Turcz.) Schischk originality in the future low performance terminals.

Objective To investigate the clinical effect of strong light therapy with cold light source in the treatment of severe neonatal hyperbilirubinemia. Methods A total of 217 neonates with severe hyperbilirubinemia who were hospitalized in Department of Neonatology in our hospital from June 2016 to January 2022 were enrolled and treated with strong light therapy with cold light source. Serum total bilirubin (STB) was measured after 4-6 h, and if STB decreased or immunohemolytic STB decreased by ≥34-50 μmol/L, strong light therapy with cold light source was continued for 18-24 h, with STB tested once during 8-12 h. When STB decreased to below 342.0 μmol/L, the treatment was changed to standard phototherapy. If STB did not decrease to the target value after 4-6 h of strong light therapy with cold light source or the early manifestation of acute bilirubin encephalopathy was observed, phototherapy was stopped and switched to exchange transfusion immediately. Results Among the 217 neonates, 2 showed no response to strong light therapy with cold light source and were treated with exchange transfusion, and the other 215 neonates achieved a reduction in STB of (40.6±14.9), (61.2±17.7), and (114.7±49.4) μmol/L, respectively, after 4-6 h, 12-14 h, and 20-24 h of strong light therapy with cold light source. The mean duration of strong light therapy with cold light source was (32.3±14.5) h. After treatment for 5-9 d, the neonates were discharged when there was no increase in STB. Hearing screening within 1 week after discharge showed normal results; brainstem auditory evoked potential (BAEP) examination was performed for 96 neonates and showed no abnormality; all neonates had normal MRI results. Of all neonates, 134 were followed up for 1 year, 43 were followed up for 1-6 months, and 38 were lost to follow-up after 1 month. The neonates who were followed up had normal physical growth, motor development, neurobehavioral assessment, BAEP, and MRI results. Conclusion Strong light therapy with cold light source has a marked clinical effect in the treatment of severe neonatal hyperbilirubinemia, and comprehensive treatment such as non-exchange transfusion strong light irradiation with cold light source can be selectively used.

The traditional coal gangue sorting methods have low efficiency, significant safety hazards, and limited application scope. The existing machine vision-based coal gangue image recognition methods are difficult to balance model recognition speed and accuracy. And the methods do not comprehensively consider the impact of different input image sizes, low important channel weights, and large convolution parameters on model precision. In order to solve the above problems, an improved tiny YOLO v3 coal gangue rapid recognition model is proposed based on the tiny YOLO v3 model. Firstly, a spatial pyramid pooling (SPP) network with multiple convolutional kernels combined pooling is introduced in the tiny YOLO v3 model to ensure that the input feature maps can be processed to a fixed size before being output. Secondly, a squeeze-and-excitation (SE) module with adjustable RGB channel weights is introduced to enhance the connections between the channels in the previous layer feature maps. It emphasizes the differences between the feature values of the interested channels and the features of different targets. It ensures the capture of key information and network sensitivity. Finally, the dilated convolution containing zero weight points is introduced to replace part of the convolution layer in the tiny YOLO v3 model. Under the premise of not adding model parameters, multi-scale context information can be captured to expand the receptive field and improve the calculation speed of the model. This model is compared with the tiny YOLO v3 model, Faster RCNN model, and YOLO v5 series models respectively. The results show the following points. ① Compared with tiny YOLO v3, the improved tiny YOLO v3 coal gangue rapid recognition model has significantly improved recognition accuracy and speed. ② Compared with Faster RCNN, the improved tiny YOLO v3 coal gangue rapid recognition model has reduced training time by 65.72%, increased recognition precision by 11.83%, increased recognition recall by 0.5%, and increased model mean average precision (mAP) by 3.02%. ③ Compared with the YOLO series model, the improved tiny YOLO v3 coal gangue rapid recognition model has a significant increase in recognition speed while maintaining the advantage of recognition precision. The results of the ablation experiment show that the improved tiny YOLO v3 coal gangue rapid recognition model has a recognition accuracy of 99.4%. It is 4.9% higher than the tiny YOLO v3 model added with the SPP network. The time to test each image is 12.5 ms, which is 1 ms less than the tiny YOLO v3 model added to the SPP network.

Objective: This study aimed to detect the quality of wheat flour quickly and non-destructively. Methods: The online detection system for wheat flour quality was built in the experiment, which mainly includes the flowing four parts: micro near-infrared spectrometer integrated device, production line adjustable speed simulation device, spectrum online acquisition and control software and online modeling and analysis software. Different modeling algorithms were used to establish quantitative analysis models for moisture, ash and gluten, and the robustness of the online quantitative analysis model was optimized. The influence of different experimental conditions on the modeling results was analyzed. Results: Partial least squares regression （PLSR） algorithm is superior to multiple linear regression （MLR） and principal component regression （PCR） algorithm for quantitative analysis of moisture, ash and gluten. The best modeling effect was obtained by using quartz glass to collect wheat flour samples online, and the best ratio of 15 speed/integration time was 6 000 ms. Conclusion: The wheat flour quality online detection system based on near-infrared spectrum analysis technology realize the nondestructive and rapid online detection of wheat flour quality.

Combustion instability is easy to occur under lean combustion of gas turbine. Analyzing and predicting the characteristics of unstable combustion is of great significance to ensure the normal operation of combustion chamber. The flame describing function (FDF) of combustion chamber was obtained by numerical simulation, and the thermoacoustic instability characteristics of combustion chamber were predicted by combining the low-order thermoacoustic network model. Firstly, the operating conditions and main frequency of oscillating combustion were obtained through the self-excited oscillation experiment of model swirler combustor.Secondly, by using large eddy simulation (LES), the response characteristics of heat release rate of flame combustion under different inlet disturbances were obtained, and the FDF was fitted. Finally, the low-order thermoacoustic network model of the combustion chamber was established, and the instability characteristics of the combustion chamber were analyzed. The results show that the oscillation characteristics predicted by the model are consistent with the experimental data, indicating that the model can predict the combustion instability characteristics from the mechanism.

As the reconstruction of global industrial chain and energy supply chain accelerates and variables in China’s energy supply security increase, it becomes inevitable for China to maximize the guarantee function of coal. Considering the characteristics of the accelerated reconstruction of the two chains, this study analyzes the impacts of the reconstruction on China's energy sector: large fluctuation of energy demand structure, restricted local production capacity, increased import risks, and increased pressure on lowcarbon transition. A fluctuation prediction model is established to predict the fluctuation range of coal demand considering these scenarios: fluctuation of fossil energy imports, output fluctuation of renewable energies, and consistent growth of energy consumption. The results indicate that coal demand will fluctuate by ±14.1% in 2025, ±16.5% in 2030, and ±18.2% in 2035, respectively. Therefore, we propose that a coal technology innovation chain should be constructed by extending and improving the coal industrial and supply chains. Moreover, future key tasks should include intelligent construction of coal mines, green development and clean transformation of coal, research and development of carbon sequestration and utilization technology in coal mine areas, and collaborative development of coal and new energies. To promote the long-term high-quality development of the coal industry in China, it is necessary to encourage the fine exploration of coal resources, strengthen the construction of coal reserves and emergency transportation capacities, improve the flexible supply of coal, enhance the support capacity for coal-to-oil and coal-to-gas production, and formulate support policies for coal industry development.

The resources of tar-rich coal in Western China are abundant and are available for large-scale development. Understanding the oil and gas resource properties of tar-rich coal and promoting the development and transformation of tar-rich coal to produce oil and gas are crucial for increasing domestic oil and gas supply, relieving external dependence on oil and gas, and ensuring national energy security of China. This study estimated the potential of tar-rich coal resources in Western China based on the current exploration results of coal resources, reviewed the current status and existing problems, and proposed the basic concept and technical conception for the development and utilization of tar-rich coal in Western China considering the new requirements for carbon reduction, intelligent green development, and compensation for oil and gas shortage. The study concluded that the development and utilization of tar-rich coal needs to focus on key technologies, including high-precision comprehensive exploration, high-recovery-rate mining, underground in-situ pyrolysis, pyrolysis and gasification integration, and in-situ pyrolysis char CO2 storage. Furthermore, we suggest that the tar-rich coal should be included in the management of unconventional oil and gas resources, scientific and technological research on the development and utilization of tar-rich coal should be strengthened, a national demonstration area should be established, and development of new energy and tar-rich coal in Western China should be coordinated, so as to maximize the special advantages of tar-rich coal as coal-based oil and gas resources and realize the low-carbon and high-value utilization of coal resources.

【Objective】 Mechanical transplanting of rice seedlings often results in some holes being missed for the transplantation. Understanding their ultimate consequence for yield and yield components is important to help improve design and implementation of mechanical transplanting. The purpose of this paper is to experimentally study the effect of the types and number of such missing holes on yield and yield components of rice of different varieties. 【Method】 Rice varieties of Kongyu 131 (KY131) and Longjing 31 (LJ31) were used as the model plants in the experiment. For each variety, there were two missing hole-seedling treatments: inter-plant (P) and inter-row (R). For the inter-plant missing, there were further three types of missing: independent type (PI), spaced type (PS) and mixed type (PM), while for the inter-row missing, there were relative type (RR), reciprocal type (RP), and mixed type (RM). For each treatment, we measured yield and yield traits of rice. 【Result】 There were significant differences in effective panicle numbers, seed setting rate, harvest index and grain yield between the two varieties and treatments. Compared with CK (without missing), the treatments reduced the effective panicles, grain numbers and yield, with the average effective panicles reduced by 13.45% and 15.44% and the average grain yield by 10.50% and 12.82%, respectively, for the inter-plant and inter-row missing holes treatments. The missing holes also changed the allocation of morphological characters of the main stem and the grain yield, though the change varies with varieties. When the number of missing holes was the same, the variation in seed setting rate of KY131 was greater than that of LJ31, and the effective panicles, grain numbers, harvest index and grain yield all decrease with the increase in the missing holes. The yield falling range of inter-row was higher than that of inter-plant, and the yield of KY131 decreases more than that of LJ31, with the average yield reduction in the former and latter being 13.01% and 10.38%, respectively, compared to CK. The main determinant of yield reduction was effective panicles and grain numbers. Correlation analysis showed a significant negative correlation between the missing holes and grain yield, with the effective panicles and 1 000-grain weight reduced being greater for KY131 than for LJ31. The number of effective panicles and grains per square meter was positively correlated with the grain yield at significant level, with the correlation coefficient for the effective panicles number being 0.954 7** and 0.890 4**, respectively, for KY131 and LJ31, the correlation coefficient for the grains number being 0.981 2** and 0.912 5**, respectively, for LJ31 and KY131. 【Conclusion】 The missing holes between plants and rows had a negative effect on many characters of rice, reduced the yield, and was not conducive to the effective combination of agricultural machinery and agronomy.

This article reported the clinical features of a rare patient with anti-metabotropic glutamate receptor 5 （mGluR5） encephalitis with mental disorders as the initial symptom， so as to provide references for clinical diagnosis and treatment. The patient was a 38-year-old male， developed pharyngeal pain as prodromal symptoms， and the main clinical manifestations included rapidly progressive memory loss， anxiety and depression， and psychomotor excitement symptoms including irritability and impulsive behaviors. The disease had a progressive deterioration. In the most severe state， the patient became unconscious in a shallow coma， with further cognitive decline， hallucinations and delusions， and lack of self-awareness. Both cerebrospinal fluid and serum anti-mGluR5 antibody were strongly positive （1∶100）. After two sessions of hormone shock therapy， the patient showed significantly improvement in consciousness， cognitive， emotional and psychiatric dimensions.

Artificially triggered lightning refers to the lightning that is artificially triggered to the ground under appropriate thunderstorm conditions. The location of artificially triggered lightning can be determined; the occurring time can be precisely stamped, and the channel-base current can be measured directly. Therefore, it's one of the effective methods to evaluate the performance of lightning location system (LLS). From the observations of artificially triggered lightning experiment conducted at the Field Experiment Base on Lightning Sciences, China Meteorological Administration from 2014 to 2019, 50 lightning flashes are selected to evaluate and analyze the performance characteristics of Guangdong-Hongkong-Macau Lightning Location System (GHMLLS).The results show that the lightning detection efficiency and stroke detection efficiency are about 96% (48/50) and 88% (233/265), respectively. The arithmetic mean, geometric mean and median values of location error are 279 m, 193 m and 202 m, respectively. The results show that there is a systematic deviation to the southwest in GHMLLS observations around the triggered lightning experiment site, which is about 170 m to the west and 50 m to the south. After correction, the arithmetic mean, geometric mean and median values of location error are reduced to 198 m, 108 m and 103 m, respectively. The linear fitting result with intercept of 0 shows that the LLS-inferred peak current of GHMLLS is about 65% of the direct measurement value of the channel-base current. Meanwhile, the arithmetic mean (median) value of the LLS-inferred peak current error is -37% (-36%). However, there is a strong positive correlation and the correlation coefficient is 0.93. The arithmetic mean (median) value of the absolute value of the LLS-inferred peak current error is reduced to 15% (12%) when the ratio of 65% is used to correct them. Among 233 return strokes of triggered lightning flashes, 16 return strokes are mistakenly classified as intra-cloud lightning, so the return stroke classification accuracy of GHMLLS is 93%. The peak currents of these mistakenly classified return strokes are lower, the stations available for locating are fewer, and the errors of location and LLS-inferred peak current are larger.In conclusion, GHMLLS have good detection efficiency and location accuracy. The return stroke classification accuracy of GHMLLS is at a high level as well. Nevertheless, there is an obvious systematic deviation in the LLS-inferred peak current of GHMLLS. In order to obtain more reliable analysis results, it's recommended to divide it by 0.65 when using the LLS-inferred peak current of GHMLLS.

Background and purpose: Laryngeal cancer is a refractory malignant tumor in otolaryngology. Radiotherapy and chemotherapy combined with surgery are often used, however, this treatment method has little improvement on the 5-year survival rate and mortality of patients, and is often accompanied by loss of laryngeal function and drug resistance. This study aimed to explore the effect of sonodynamic therapy (SDT) mediated by nanoacoustic sensitizer T-G-C particles on inhibiting human laryngeal cancer cells, and to provide a new non-invasive treatment for laryngeal cancer. Methods: Based on the synthesized T-G-C nanomaterials, the uptake of nanomaterials by Tu686 cells was evaluated under confocal laser scanning microscope, and the cell survival and apoptosis were evaluated by cell counting kit-8 (CCK-8) and Annexin Ⅴ- fluorescein isothiocyanate (FITC) reagent in the presence of ultrasound. BALB/c nude mouse xenograft model was established. The weight and tumor changes of mice were recorded during the treatment by injecting different types of drugs and ultrasonic irradiation in the tumor area, and the treatment effects were analyzed and compared. The apoptosis and necrosis of tumor cells and the production of reactive oxygen species (ROS) were compared by H-E, TUNEL, Ki-67 and DHE stainings. Results: Nanomaterials and cells incubated for 24 hours had no obvious toxicity, only led to the decline of cell survival rate under ultrasonic stimulation, and the cells showed mainly early apoptosis and late apoptosis. In the animal experiment, only after intratumoral injection of drugs and ultrasound treatment on the 1st, 3rd, 5th and 7th days, the tumor growth of mice in T-G-C+ultrasound group was significantly inhibited, and the tumor inhibition rate is 100%. After 16 d of treatment, obvious red fluorescence could be seen in the tumor area after ultrasound irradiation, which demonstrated that the core of tumor inhibition was the production of ROS. Conclusion: Biocompatible T-G-C nanoparticles stimulate the synergy of SDT and piezoelectric therapy when stimulated by ultrasound, and promote the early and late apoptosis of laryngeal cancer cells through ROS, which provides a combined treatment method for laryngeal cancer and promotes the application of multidisciplinary therapy in department of otolaryngology.

ObjectiveTo study whether diatoms can enter the body through the lymphatic system of the digestive tract.MethodsTwenty experimental rabbits were divided into the test group and the control group randomly, and intragastric administration was performed with 20 mL water sample from the Pearl River and 20 mL ultrapure water, respectively. After 30 min, lymph, lungs， livers and kidneys were extracted for the diatom test. The concentration, size and type of diatoms were recorded.ResultsThe concentration of diatoms of the test group was higher than that of the control group （P

ObjectiveTo retrospectively analyze diatom test cases of corpses in water and discuss the value of quantitative analysis of diatoms in the diagnosis of drowning.MethodsA total of 490 cases of water-related death were collected. They were divided into drowning group and postmortem immersion group according to the cause of death. Diatoms in lung, liver, kidney tissue and water sample were analyzed quantitatively by microwave digestion-vacuum filtration-automated scanning electron microscopy （MD-VF-Auto SEM） method. The ratios of content of diatoms in lung tissue and water sample （CL/CD） were calculated.ResultsThe results of diatom test for three organs （lung, liver and kidney） were all positive in 400 cases （85.5%）; the content of diatom in lung, liver, kidney tissues, and water samples of drowning group were （113 235.9±317 868.1）, （26.7±75.6）, （23.3±52.2） and （12 113.3±21 760.0） cells/10 g, respectively; the species of diatom were （7.5±2.8）, （2.6±1.9）, （2.9±2.1） and （8.9±3.0） types, respectively; the CL/CD of drowning group and postmortem immersion group were （100.6±830.7） and （0.3±0.4）, respectively.ConclusionQuantitative analysis of diatoms can provide supportive evidence for the diagnosis of drowning, and the parameter CL/CD can be introduced into the analysis to make a more accurate diagnosis of drowning.

ObjectiveTo study the effects of temperature and time for diatoms digestion and find out suitable digestive temperature and time.MethodsEighty pieces of liver tissues were collected, each piece of tissue was 2 g, and 2 mL Pearl River water was added to each piece of tissue. The digestion temperature was set at 100 ℃, 120 ℃, 140 ℃, 160 ℃, 180 ℃ and the digestion time was set at 40, 50, 60, 70, 80 min. The liver tissue and water mixture were divided into 8 portions in each group. All the samples were tested by microwave digestive - vacuum filtration - automated scanning electron microscopy method. The quantity of diatom recovered and the quality of residue on the membrane were recorded.ResultsWhen the digestion time was set to 60 min, there were statistically significant differences in the number of diatoms recovered at different temperatures （P0.05）.ConclusionThe effect of diatom digestion is related to temperature and time. When the digestion temperature was 140 ℃ and the digestion time was 40, 50 and 60 min, it is favorable for diatom test.

Tropical cyclone is one of the major weather disasters affecting coastal areas, which can produce high winds and heavy rains, posing serious threats to the safety of people's lives and property in coastal areas. China is in the Northwest Pacific, which is affected more frequently by tropical cyclones than any other area in the world. Therefore, it is of great significance to strengthen the research on tropical cyclone in the Northwest Pacific. In recent years, observations and studies have proved that lightning activity often occurs in tropical cyclone, which is closely related to the convective evolution and intensity variation of tropical cyclone. Based on data of lightning imaging sensor (LIS) carried on the TRMM (Tropical Rainfall Measuring Mission) satellite during 1998-2014, the characteristics of lightning properties (including duration, extended distance, channel area and optical radiant energy) of tropical cyclone in the Northwest Pacific are studied by establishing the lightning dataset of tropical cyclone in the region. The results show that all attributes of tropical cyclone lightning present lognormal distribution characteristics, and the distribution of peak values of these attributes is consistent with that of the Northwest Pacific thunderstorm system, but different from that of East Asia land thunderstorm system. The maximum of tropical cyclone lightning tends to occur over the ocean at tropical depression intensity levels. The maximum proportion of lightning in the outer rain belt is the lowest, while the maximum proportion of the duration and optical radiant energy of lightning in the inner core is the highest. The tropical cyclone lightning duration of different intensity levels has no significant difference, but the mean value of lightning spatial scale and optical radiation energy of tropical storm are lower than those of tropical depression and typhoon. For different areas of tropical cyclone, the maximum value of duration and optical radiant energy of core lightning decrease with the increase of distance between lightning and tropical cyclone center. In terms of maritime-continental contrasts, tropical cyclone lightning occurs over the ocean with larger spatial scale and stronger optical radiant energy than that over the land, while lightning duration is roughly the same. After tropical cyclone landing, the spatial scale of lightning decreases and the optical radiant energy of lightning weakens. Compared with non-tropical cyclone lightning, tropical cyclone lightning has shorter extension distance, narrower channel area and weaker optical radiant energy, but the average duration of lightning is longer.

Multimodal data modeling can effectively overcome the problem of insufficient information in a single mode and can greatly improve the performance of model. However, not much progress has been made in quantifying the confidence of neural network models, especially for multimodal fusion models. This paper proposes a method based on embedding, which calculates the local density estimation in the embedding space by calculating the distance between samples, and then calculates the confidence score of the model. The proposed method is scalable and can be used not only for a single modal model, but also for the confidence measurement of multimodal fusion model. In addition, it can also evaluate and quantify the influences of different modal data on the multimodal fusion model.

Since the beginning of this century, three types of coronavirus have widely transmitted and caused severe diseases and deaths, which strongly indicates that severe infectious diseases caused by coronavirus infection are not accidental events. Coronavirus-infected diseases are mainly manifested by respiratory symptoms, with multiple organ dysfunctions. Precisely investigating the pathological process, characteristics and pathogenesis of coronavirus-infected diseases will be beneficial for us to understand clinical manifestations and provide targeted suggestions on prophylaxis and treatment. This paper briefly reviews the pathological findings of three known coronavirus-infected diseases, and attempts to construct the pathological spectrum of coronavirus-infected diseases, aiming to provide reference and thinking for autopsy, histopathological examination and animal infection model study of coronavirus-infected diseases.

In order to solve the problem of deep rock roadway stability control, a large-size three-dimensional numerical calculation model of “bolt support and concrete shotcrete layer” was established by means of numerical simulation and field industrial test. The control effect of bolt and shotcrete support parameters on roadway deformation was systematically studied. The research showed that: with bolt pre-tightening force, spacing, the increase of the anchorage length, to effectively control the deformation of surrounding rock of roadway, and is subject to the control of pre-tightening force and the anchoring length is more significant, and the appropriate anchor length can effectively control the deformation of roadway, the strength of spraying layer and the thickness is small, the structure of spray layer will cause the deformation of roof and floor of roadway to shift to two sides, when the spray layer reaches a certain strength and thickness, spray layer structure can improve the overall control effect of surrounding rock of roadway. Based on research results, we design the spray anchor net supporting technology and parameters, and the industrial test its rationality was verified.

Objective To investigate the protective effect of pericyte (PC)-derived microvesicle (MV) on lung injury in septic rats. Methods PC-MV was harvested by differential centrifugation and identified by transmission electron microscopy (TEM) and flow cytometry (FCM). Forty SD rats of either sex (12~14 weeks old, about 220 g) were randomly divided into 4 groups (n=10): normal group, PC-MV control group (normal rats with PC-MV injection), sepsis group (cecal ligation puncture, CLP), and PC-MV treatment group(septic rats with PC-MV injection). The effects of PC-MV (1×107 per rat) on pulmonary vascular permeability in septic rats were observed by measuring the wet/dry weight ratio of lung and Evans blue dye exudation in lung tissue, those on pulmonary tissue function were determined by lung pathological sections and arterial blood gas analysis, and those on inflammation were observed by detecting the levels of inflammatory factors. Results Compared with the normal group, the pulmonary function was obviously impaired in the septic rats, which was manifested as destruction of lung tissue structure, exudation of a large number of red blood cells and inflammatory cells, and decrease of oxygen partial pressure (PaO2, 33.6%) and increase of carbon dioxide partial pressure in the arteries (PaCO2, 47.5%). In septic rats, pulmonary vascular permeability was significantly increased, which was manifested as increment of lung wet/dry weight ratio, increment of Evans blue permeability in the lung, and increased levels of TNF-α and IL-6 (P < 0.01). Exogenous PC-MV improved pulmonary structure, restored the arterial blood gas (compared with the normal group, PaO2: decreased by 17.7%; PaCO2: increased by 26.9%), reduced inflammatory factor exfiltration (compared with the sepsis group, TNF-α level: decreased by 10.7%; IL-6 level: decreased by 23.9%) in PC-MV treatment group when compared with the sepsis group), and significantly protected pulmonary function of septic rats. Conclusion PC-MV has a protective effect on lung injury in septic rats.

A thunderstorm feature dataset (TFD) is built up based on the black body temperature (TBB) product and cloud classification (CLC) product of FY-2E meteorological satellite as well as the lightning data of the World-Wide Lightning Location Network (WWLLN). In the TFD, thunderstorm cloud is determined when there is WWLLN lightning in the area with TBB not higher than -32℃ or its fitted ellipse. The characteristic parameters of thunderstorms including time, location, morphology, structure, and lightning activities are obtained to establish the TFD. Based on the dataset, thunderstorms in the land of China and the adjacent seas are analyzed after the quality control.The results show that South China, Southwest China, Eastern and Central of Tibetan Plateau and South China Sea are the areas with most frequent thunderstorm activities. North China and Northeast China are two areas with relatively frequent thunderstorm activities in the north part of China. Meanwhile, thunderstorm activity is the weakest in Northwest China.The seasonal variation of thunderstorm activity shows obvious differences between land and sea. The active stage of thunderstorms on land is from June to August. In high latitudes, the peak appears earlier. There is a peak of thunderstorm activity in the South China Sea around May, and another peak after August. The lower the latitude is, the later the second peak appears. The peak time of thunderstorm activity in diurnal variation in most parts of the land is from 1400 BT to 2000 BT and the peak of thunderstorm activity in adjacent sea areas mainly occurs in the morning. In the Sichuan Basin, thunderstorms are more frequent in the early morning. The diurnal variation of thunderstorm activity in the South China Sea is relatively weak.The area of thunderstorm cloud with TBB not higher than -32℃ follows a log-normal distribution, with the peak interval being 1×103-1×104 km2, and the average area is 3.0×104 km2. The area of thunderstorm cloud over the sea is obviously larger than that of land, and the South China Sea has the largest area of thunderstorm clouds. On the land, the area of thunderstorm clouds in the east is larger than that in the west, and the average area of thunderstorm clouds greater than 1.2×105 km2 can be predominantly found in the first step of Chinese topography. Meanwhile, there is a local center with an average area of thunderstorm clouds greater than 1.2×105 km2 in the Qaidam Basin.

Water mobility is an important factor affecting the production of coalbed methane. It is of great significance to analyze the effect of porosity and permeability on water mobility for the development of coalbed methane in Jixi Basin. In order to analyze the influence of porosity and permeability of coal reservoir on the water mobility, we performed low field NMR, permeability and water saturation experiments on the main coal seams of different mining areas in Jixi Basin.The results show that: ①Adsorption pores are relatively developed and the average proportion is 58.36%, while the seepage pores and fractures are similarly developed, with the average proportion of 21.23% and 20.41%, respectively.The seepage pores and fracture are well connected; ②The centrifugal force that makes the studied coal seam reach the bound water state is 1.38 MPa, under which the movable water can be discharged from half-open or open pores with a radius of more than 0.1 μm.By which the movable water saturation is 27.84%-60.87%, with an average of 37.86%; the irreducible water saturation is higher which is calculated as 39.13%-72.16%(av.62.14%).With the increase of pressure, the movable water flows first along the fracture, and then flows out through the seepage pores, while the irreducible water mainly existing in the adsorption pores is difficult to flow because of the large capillary resistance during centrifugation; ③There are obvious differences in water mobility and occurrence in coal samples with similar metamorphic degree, which may be one of the reasons for the difference of water and gas production in different block's CBM wells; ④The movable water in the study area is easy to flow out from coals with higher movable water saturation, greater permeability and more developed pore throat of more than 1 000 nm, but the water is difficult to flow out from coals with lower movable water saturation and more developed pore throat of 0-100 nm in which water is trapped.

With the ongoing global climate change, extreme heat events have a profound negative impact on the socio-economic development of cities. In this study, through a portrayal of the urban vulnerability pattern of cities under extreme heat stress in China, as well as an in-depth analysis of its influencing factors, a foundation was laid targeting reduction in the risk of extreme heat event occurrence in these cities and building a healthy urban environment. Herein, the municipal districts of 280 cities in China were considered as the research targets. On the basis of meteorological observation data, census data, and socio-economic statistics, the urban vulnerability assessment index system for extreme heat was constructed from the standpoint of three dimensions: Exposure, sensitivity, and adaptability. The set pair analysis method and the vulnerability index model method were used to comprehensively calculate the indices of urban exposure, sensitivity, adaptability, and vulnerability to extreme heat. Thereby, the spatial and temporal distribution patterns of urban exposure, sensitivity, adaptability, and vulnerability to extreme heat in the main cities in China for 1990, 2000, and 2010 were revealed, following which the factors affecting the urban vulnerability to extreme heat were discussed. The following conclusions from three standpoints were ultimately drawn. First, from 1990 to 2010, the urban exposure index to extreme heat in China gradually increased, the urban sensitivity index first rose and then declined, and the adaptability index demonstrated a slow decline. The overall spatial distribution of urban exposure to extreme heat is high in the south and low in the north, while the urban sensitivity and adaptability to extreme heat are widely distributed and scattered throughout the country. Second, from 1990 to 2010, the number of cities with a high vulnerability to extreme heat showed an overall trend of increase, accounting for 24%, 28%, and finally 62% of highly vulnerable cities, which implies that the vulnerability to extreme heat in China gradually increased. From 1990 to 2000, the pattern of urban vulnerability to extreme heat in China changed slightly. In 2010, the number of cities with high vulnerability increased sharply, and the distribution range expanded from the south to the north of China. Further, the overall distribution of urban vulnerability to extreme heat was high in the south and low in the north. Third, urban vulnerability to extreme heat is mainly affected by the regional climate conditions, natural environment, and differences in urban development levels. The average monthly temperature in summer and heat island intensity both have a significant positive impact on the urban vulnerability to extreme heat. On the contrary, the per capita local fiscal revenue, average precipitation in summer, output value of the secondary industry as a percentage of GDP, elevation, maximum wind speed, and per capita investment in fixed assets all have a significant negative impact on the urban vulnerability to extreme heat. However, the positive impact of the average monthly temperature in summer on urban vulnerability to extreme heat is far greater than the negative impact of social and economic conditions. Therefore, it can be inferred that urban vulnerability to extreme heat is mainly affected by the regional temperature environment.

Aimed at the problem of instability and deviation of multiple training model in limited samples, this paper proposes a method of distance metric learning based on the Gaussian mixture model, which can solve this problem more reasonably by dividing the dataset. Distance metric learning relies on the excellent feature extraction capabilities of deep neural networks to embed the original data into the new metric space. Then, based on the deep features, the Gaussian mixture model is used to cluster the analyzer and estimate the sample distribution in this new metric space. Finally, according to the characteristics of sample distribution, stratified sampling is used to reasonably divide the data. The research shows that the method proposed can better understand the characteristics of data distribution and obtain a more reasonable data division, thereby improving the accuracy and generalization of the model.

Up to 81. 5 d B high noise occurs in the range hood fitted with original process impeller. This paper presents a method of combing experiment and numerical simulation to reduce the noise level of the range hood under the maximum working condition.First,noise and vibration test of range hood and excitation resource are conducted on a range hood fitted with impellers made by original approach and new process,respectively. Then,the differences between the processing technologies in making the two impellers are analyzed. Modal analysis of the above impellers are performed to determine the cause of the vibration noise. Results show that the thermal stress is generated in the production process,which changes the natural frequency of the impeller made by the original process.Moreover,the changed natural frequency is close to the excitation frequency,which leads to the severe vibration noise. However,less thermal stress is produced in the production process of the new impeller by adding one more step in the production. The final modified procedure is to increase the natural frequency of the impeller by thickening the impeller rear lap and use the original production process. Thus the problems caused by severe vibration noise of the impeller gets solved successfully.

The fracture reason analysis of oscillator wire was performed of vertical log-periodic antenna,which mounted somewhere in the north of China in 2018. Through the analysis of two possibilities of brass material fracture,the results show the reason of brass oscillator wire fracture is fatigue damage. The main causes of fatigue damage are the tension adjustment of the antenna cable and the large local temperature difference,which results in the stress of the oscillator wire far exceeding the original design stress. According to the reason breakage of the brass oscillator wire,an improved scheme is proposed to meet the antenna requirements in this area.

Lightning activity in a convection cell that occurred in Guangzhou of China on 7 May 2017 dominated by heavy warm cloud precipitation and its relationship with the precipitation structure of the cell are disscussed, using three-dimensional lightning location data of the Low_Frequency E-field Dection Array (LFEDA) in the Field Experiment Base on Lightning Sciences, China Meteorological Administration (CMA_FEBLS) and Guangzhou polarimetric radar observations. According to the ground precipitation obtained by radar inversion, the maximum cumulative precipitation from 0000 BT to 0400 BT in the cell dominated by warm cloud precipitation is 261 mm. The cell produces a total of 1250 detected lightning flashes within 4 h, with the ratio of cloud-to-ground flashes being about 24%. Lightning discharges mainly occur in the height range of 4-12 km, corresponding to the isotherm layers between approximately 0℃ and -40℃. The height and isotherm associated with the peak-frequency lightning discharges are about 8.5 km and -19℃, respectively. The heavy rainfall cell represents general tripolar charge structure, i.e., the upper positive charge region, middle negative charge region and lower positive charge region, with the negative charge core being between approximately -8℃ and -15℃ layers. The region featuring lightning discharges and dominated by dry snow account for about 82% of all, while the ratio for the region featuring lightning discharges and dominated by graupel account for about 11%. Most graupel-dominating regions associate with lightning discharges are located between 4 km and 8 km layers. This may be related to the weak convection in the cell dominated by warm cloud precipitation. Total lightning rate show relatively significant correlations with the 30 dBZ radar echo top height and volumes of the regions where radar echoes are greater than 20 dBZ and heights are larger than -20℃ level. The average height of lightning discharges is well related with the 20 dBZ radar echo top height and volumes of regions where radar echoes are greater than 30 dBZ and heights are larger than -20℃ level. Relative prominent corresponding relationship is also found between total flash frequency and maximum precipitation intensity. Meanwhile, the rainfall per flash is in the order of 107 kg/fl.

Rocket-triggered lightning experiment conducted in Field Experiment Base on Lightning Sciences, China Meteorological Administration (CMA_FEBLS) provides a good opportunity to study the discharge process and its related electromagnetic effects. During the experiment, two medium-low frequency magnetic antennas are deployed at different distances from the rocket launch site, named close antenna (about 80 m) and far antenna (about 1.9 km), respectively, and magnetic fields are observed with high sensitivity by two antennas. Combined with the synchronous channel-base current and fast electric fields, electromagnetic characteristics of initial continuous current are analyzed. Benefitting from the expansion of the bandwidth of the antenna, magnetic pulse signals can be observed throughout the triggered lightning, including the initial magnetic pulse (IMP), magnetic pulse of the signal quiet period, the magnetic pulse burst (MPB) and the regular magnetic pulse (RMP). IMPs can be divided into two categories (i.e., impulsive and ripple pulses) according to the discernibility of separation between individual pulses. Impulsive pulses are well simulated by the transmission-line model, which suggests that these pulses are generated by leader current pulses propagating downward along the steel wire. Magnetic pulses of the signal quiet period are observed for the first time. The mean pulse width and inter-pulse interval of these pulses are about 1 μs and 14 μs, respectively, which indicates that the propagation of upward leaders during the stage is in the form of small-scale breakdown. The MPB can be observed by both close and far antennas, and the mean inter-pulse interval of the MPB(24.5 μs) is larger than that of the signal quiet period pulse. Furthermore, the channel-base current during the stage of MPB increases to dozens of hundreds of amperes, so it can be concluded that the electric field condition is conductive to the development of the upward leaders. In addition, the magnetic signal recorded at close distance indicates the physical process leading to initial continuous current pulse (ICCP), M-component as well as the direct measurement of current enhancement at the channel base, due to the charge transfer in the ICCP or M-component. Magnetic antennas can also record the regular magnetic pulses (RMPs) that are attributed to the interception of recoil leader with existing lightning channel. Inter-pulse intervals of RMPs are one order smaller than that of MPBs and IMPs, and observations may reflect differences between the positive polarity breakdown and the negative polarity breakdown of leaders.

The discharge process is often discussed in the lightning physics. VHF (very high frequency) observations play an important role in studying lightning discharge processes, because they show where air breakdown occurs. Triggered lightning flashes are ideal research objects, because they are generated in a fixed time and place. Regular experiments of triggering lightning have been conducted by Chinese Academy of Meteorological Sciences since 2006, and 189 lightning flashes are triggered successfully. Besides regular observations, such as fast/slow antenna, channel-based current and high-speed video, the continuous interferometer (CINTF) is developed and deployed at the site for triggered lightning after 2016 in order to observe detailed discharge processes. The CINTF can provide high-precision location with time resolution of around 1 μs.A multi-stroke triggered lightning with 8 return strokes is observed by a self-developed lightning continuous interferometer during Guangdong Comprehensive Observation Experiment on Lightning Discharge on 11 June 2019. The whole discharge processes, including precursor current pulse, initial precursor current pulse, initial continuous current and return strokes, last for about 1600 ms. The channel-based current, electric field change and radiation source positions are obtained. CINTF results show that the radiation signal generated from discrete precursor current pulse with a minimum value of about 8 A can be detected. The average transfer charge of initial precursor current pulse is twice as much as that of the precursor current pulse. During the initial continuous current stage after continuously developing of the upward positive leader, the obviously forward channel extension is the main discharge form at the beginning, and then the extension can be accompanied by discontinuously backward propagation, and recoil leader often occurs in the following stage. M-component in the ICC stage is caused by two discharge processes:Forward positive streamer (or leader) or recoil leader generated in the existing channel. Multi recoil leaders occur during the whole M process, which maintain M discharge. The main discharge form in return stroke stage is recoiling discharge. There are multi recoil leaders before return strokes, however, most of them cannot develop to ground, keep as an attempted leader until the last leader-stroke occurs. Adjacent two strokes with a short duration time of 4.5 ms have the same optical channel in optical images, but they are obviously different in development paths, which lead to a very short RS interval.

The research on rocket-triggered lightning has made great progress since 1967. Various parts of rocket-triggered lightning are studied, but differences between initial stages of different types of rocket-triggered lightning and the relevance on each part of rocket-triggered lightning is still not well understood. Based on the rocket-triggered lightning current data obtained from Guangdong Comprehensive Observation Experiment on Lightning Discharge in Field Experiment Base on Lightning Sciences, China Meteorological Administration, two types of rocket-triggered lightning are classified considering the existence of return storke(RS)and the length of the initial continuous current(ICC). Differences of rocket-triggered lightning in different categories and the correlation between various parts are analyzed. Firstly, the difference between the rocket-triggered lightning with return strokes and the rocket-triggered lightning without return strokes is obvious. The precursor current pulse(PCP)and initial precursor current pulse(IPCP)average peak current, IPCP transfer charge, ICC average current and total transfer charge and duration of lightning with RSs are greater than those of lightning without RSs. Secondly, longer ICC duration corresponds to higher average peak current, first return charge and first RS peak current, PCP and IPCP peak current, PCP and IPCP average transfer charge of triggered lightning. It is also found that the average peak value of PCP and IPCP has the strongest correlation with ICC duration. The larger the average peak value of PCP and IPCP is, the longer the ICC duration is. It's also found that during the ascent of the rocket, the transfer charge of PCP tends to increase as the altitude of the rocket increases. There are some PCP pulse clusters that cannot produce a continuous upward leader (UPL), and it fails to produce an ICC. The average transfer charge of the PCP cluster is smaller than the average transfer charge of the initial precursor current pulse cluster (IPCP). According to the analysis of data, one of the conditions for the PCP cluster that fails to generate ICC to become IPCP is that the average transfer charge is greater than 25.91 μC.

The tropism of six species of insect pests in stored grain to six kinds of colours was researched in laboratory by color correction.The results showed that the tropism of six species of insect pests in stored grain to different colors mostly changed with time, and the behavioral responses of the Tribolium castaneum(Herbst)、Tribolium confusum Jacquelin du Val、Sitophilus oryzae (linnaeus)、Sitophilus zeamais Motschulsky to different colors were significantly different within a specific period of time (P≤0.05).Red、orange and black had obvious attracting effect on Tribolium castaneum (Herbst), with the highest trapping rates of 76.23%、39.55%、49.57%; Red and black had obvious attracting effect on Sitophilus zeamais Motschulsky,with the highest trapping rates of 38.48%、38.67%.The Liposcelis bostrychophila Bodonnel and Liposcelis decolor (Pearman) showed evasiveness to the most of the six colors tested.Red and purple had evident evasive effects on the Liposcelis bostrychophila Bodonnel and Liposcelis decolor (Pearman), with the highest evasive rates of 70.29% and 54.46%.The results can provide reference for the development of color traps to trap and monitor pests in stored grain.

The periodic structure coating maintenance process based on the selective surface was proposed. The coating of oxidized Fe and carbonyl iron particles (CIPs) was obtained by the corrosion method. The morphology of particles after corrosion was characterized by the scanning electron microscopy (SEM). The permittivity and permeability of the absorber adding the hybrid particles were tested in 8-18GHz, and the oxidized coating parameter could be calculated using the effective medium rule. Effects of the corrosion process and the maintenance process were analysed. The results show that as the CIPs oxidized in the coating surface, the coating's absorbing property was weakened as the oxidization thickness is increased, and the increment value of reflection loss (RL) is about 2dB. When the coating thickness is set as 0.8mm, the maintenance performance is unsuitable. However, if the coating thickness is increased to 1mm and the oxidization thickness is 0.1mm, the maintenance performance is improved, then the absorbing band can be widened in 10-18GHz and the RL decrement is about 2dB correspondingly.

Objective To explore the clinical manifestation, pathological features, treatment regimen and prognosis of primary thyroid lymphoma (PTL) patients. Methods We analyzed retrospectively the clinicopathologic features, diagnosis and treatment of 13 PTL patients confirmed by pathology. Results All patients were B cell non-Hodgkin lymphoma, including three cases of extranodal marginal zone lymphoma and 10 cases of diffuse large B cell lymphoma; 10 patients were in the early stage (stage Ⅰ and Ⅱ) and three patients with advanced stage (stage Ⅲ-Ⅳ); only one patient accepted surgical resection and the rest accepted multi-drug chemotherapy or combined with local radiotherapy; the median survival time was 99.5 months and the 5-year survival rate was 100%. Conclusion The incidence of PTL is low. Thyroid nodules are the main symptoms. More than half of them are accompanied with Hashimoto's thyroiditis. Main pathological type is B cell non-Hodgkin lymphoma. CHOP-based chemotherapy is effective for most of the patients with good prognosis.

For achieving the requirement of real-time video monitoring which is located in the circuit cut-over operating point of the substation of the National Grid Nanjing Branch,China Telecom Nanjing Branch developed a new real-time video monitoring system which was based on internet of things technology and 4G wireless transmission network,by creating a smart pipeline based on 4G VPDN (virtual private dial-up network).The new system has solved the problem that the cable can not be used due to the frequent changing of the circuit cut-over operating points of the substation.

Objective To investigate the relationship between the level of the soluble triggering receptor expressed on myeloid cell (sTREM⁃1) in the gingival crevicular fluid (GCF) of individuals and peri⁃implantitis. Methods 46 pa⁃ tients (75 implants) with different severities of peri⁃implantitis and 18 patients (75 implants) without peri⁃implantitis were selected in this study. The concentrations of sTREM⁃1 in GCF with different types of peri⁃implantitis were detected by enzyme⁃linked immunosorbent assay (ELISA). The peri⁃implantitis peroxidase depth (PPD), the distance from the shoul⁃ der of the implant to the bottom of the bony defect (DSB), the modified sulcus bleeding index (mSBI) and the modi⁃ fied plaque index (mPLI) were recorded. The correlation between PPD, DSB, mSBI, mPLI and sTREM⁃1 was analyzed. Results The concentrations of sTREM⁃1 in GCF in mild, moderate and severe peri⁃implantitis group were significant⁃ ly higher than those in healthy group (P < 0.05). The concentrations of sTREM ⁃ 1 in GCF in severe peri ⁃implantitis group were significantly higher than those in mild and moderate group (P < 0.05). There was no significant difference in the concentration of sTREM⁃1 in GCF between mild peri⁃implantitis group and moderate group (P > 0.05). In addi⁃ tion, there was a significant positive correlation between the concentration of sTREM ⁃ 1 and PPD, DSB, mSBI, mPLI. Conclusions The concentration of sTREM ⁃1 in GCF is closely related to the severity of tissue inflammation around implant.

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