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Table of Content

    19 August 2023, Volume 51 Issue 4
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    Research Progress on Silicon-Carbon Composite Anode Materials Prepared by Chemical Vapor Deposition
    FU Xiangnan1，XU Yuanjian1，CHAI Jingchao1，ZHANG Yumin1，WANG Haiping1，ZHENG Yun1，XIE Ming1，LIU Zhihong1，YAN Bo2，YAN Weixiong*3
    2023, 51(4):  5-16.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.001
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    At present，it is one of the most effective ways to prepare silicon-carbon composite anode materials by compositing the silicon materials with high specific capacity and the carbon materials with stability. Among the many preparation processes of silicon-carbon composite anode materials，the silicon-carbon composite anode prepared by chemical vapor deposition（CVD） has the advantages of high charging/discharging efficiency，good cycle stability，facile process，and is suitable for mass production. This paper summarized the research progress of preparing silicon-carbon composite anode materials by chemical vapor deposition. From the perspective of silicon-carbon composites structure，such as coreshell structure， yolk-shell structure， porous structure， and embedded structure， the structural design and battery performance of different types of silicon-carbon composite anode materials were introduced， and their advantages and existing the problem were discussed. Finally，the application of silicon-carbon composite anode materials prepared by CVD was summarized，and we prospected the future of industrialization of silicon-carbon composite anode materials.
    Equivalence of Limit Distributions of a Sum and a Maximum Sum of Pair-wise PQD Sequences
    YANG Wenquan
    2023, 51(4):  17-22.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.002
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    We prove the equivalence of limit distributions of a sum and a maximum sum of pair-wise PQD sequences on the condition of exiting finite variances. That is，the result of Kruglov（1999）is also valid for pair-wise PQD sequences.
    Gorenstein Projective and Gorenstein Injective Properties of Modules over Special Rings
    LI Yanwu，CHEN Qianqian
    2023, 51(4):  23-28.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.003
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    The Gorenstein projective and Gorenstein injective properties of modules over rings were studied. Firstly，under the framework of an Artin ring，the sufficient and necessary conditions for any left R-module to be a Gorenstein projective module and a Gorenstein injective module were discussed by the characterization condition of a special ring. Then，the Gorenstein projective and Gorenstein injective properties of modules over a general ring were described in terms of the embeddability of the right R-module to free Rmodules and projective modules，as well as the zero-dependent lifting chain. The results of the existing literature were partially extended.
    The Limit of Sum Form Obtained by Uniformly Convergent
    SHU Wenhao，KUANG Siying，HU Xiaoli
    2023, 51(4):  29-35.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.004
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    The limit of sum form is one of the most important limit problem and has a wide range of applications in all branches of mathematics. It is complex，diverse，and flexible， and there is usually no fixed method to solve it. A postgraduate examination question about the uniform convergence of function sequences triggered the author to think about the limit of sum form with function sequences. By deforming and arranging the limit of the sum form properly and constructing the uniform convergence function，a series of the limit of the sum form with function sequence problems can be solved skillfully. We give rigorous reasoning proof to the conclusion and provide general ideas for solving such problems. Through the analysis of typical examples， it is helpful for beginners to understand and grasp such problems.
    A Study of Production Class Raw Material Procurement Problem Based on Entropy Power-TOPSIS-DE Modle
    ZHU Yukun，LI Heng，LIANG Yitian，XIONG Xin
    2023, 51(4):  36-46.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.005
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    For the 0-1 planning problem of optimal cost in the process of raw materials ordering and forwarding，evaluating the supply capacity of 402 suppliers and the loss rate of forwarders on the basic situation of a construction and decoration panel manufacturer，we designed a procurement and transportation framework of the supply chain problem based on the entropy power-TOPSIS-differential evolutionary（DE）algorithm by constructing the objective function and constraints. Firstly，the overall quantitative analysis of the order quantity and supply quantity of the raw material suppliers of this enterprise in the past 240 weeks was carried out，and some evaluation indexes such as order quantity of suppliers， order time of suppliers，total supply quantity of suppliers，supply stability rate，supply time， and average supply quantity were constructed. Then，a comprehensive evaluation of all suppliers was made by the entropy power-TOPSIS model. Finally，108 high-quality suppliers were selected for supply. Another aspect，based on the decision variable of whether the enterprise chose the supplier and the objective function of the minimum purchasing cost， the optimal purchasing strategy was obtained by the DE algorithm. Meanwhile，the optimal transportation scheme was obtained by the DE algorithm based on the objective function of the lowest loss rate.
    Design of Remote Inspection System for Welding Seam Image Based on YOLOv5
    SUN Chao ，FENG Yaolong ，ZHANG Hong ，LI Shaowei
    2023, 51(4):  47-56.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.006
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    Aiming at the problems of welding seam image transmission，storage，and detection，this research designed a remote welding seam image detection system based on YOLOv5. The hardware system consisted of the camera module， power step-down module，main control unit module，and radio frequency module. The software system was developed by the WinForms application program，and the original welding seam image and marked image were displayed on the monitoring end in the form of a visual interface. In this study，an attention mechanism was added to the YOLOv5 network model to enhance the ability of weld seam feature extraction. A small target detection layer was added to the Neck part of the YOLOv5 model to enhance the generalization ability of the model. The YOLOv5 convolution neural network was trained with 870 images and tested with 130 images. The experimental results showed that the mAP value of the improved model was finally stable at 93. 42%，0. 53% higher than that of the original model.
    Real-time Pressure Dynamics Research on Independent Nozzle Control of Boom Sprayer
    ZHENG Shenyu ，ZHAO Xueguan ，ZHANG Xinwei ，ZHENG Kang ， ZHAI Changyuan ，YI Kechuan
    2023, 51(4):  57-65.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.007
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    The change in spray pressure causes the change in spray flow rate and finally affects the uniformity of the spray. In this paper，the real- time nozzle tip pressure controlled by the independent nozzle of the boom sprayer was taken as the research object，the independent nozzle control system and nozzle tip pressure data acquisition system were built based on the C37 controller. The pressure dynamics of the nozzle tip when 5，10，or 15 nozzles were opened and closed at the same time were collected，and the pressure dynamic characteristics were analyzed. The real- time pressure dynamic test results of independent nozzle control showed that the number of nozzle openings and closings had a significant influence on the nozzle tip pressure. The opening position of the nozzle had no significant influence on the pressure change of the nozzle tip，and the pressure changes of the nozzle tip collected by all pressure sensors were consistent. At the same time，in the process of opening and closing 5，10，or 15 solenoid valves，the pressure at the nozzle tip varied during 6. 0% and 20. 0%，and the spray flow rate varied during 3. 20% and 10. 90%. Using the independent nozzle control system and nozzle tip pressure data acquisition system built in this paper，the real- time pressure dynamics of independent nozzle control of boom sprayers were obtained，which provided a reference for spray uniformity research of independent nozzle control boom sprayers on a farm and the research of the target spray technology.
    Causes Analysis of Severe Complications After Bronchoscopic Balloon Dilation
    HU Zhimin ，JING Qiusheng ，LIU Min ，WU Mingdi ，CHEN Xianxiang
    2023, 51(4):  66-72.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.008
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    Objective To analyze the causes of severe complications caused by bronchoscopic balloon dilation in three cases of Wuhan Pulmonary Hospital，to improve the safety of balloon dilation and reduce or avoid severe complications. Methods Three cases of severe complications were tracheal-bronchial membrane laceration， pneumomediastinum and subcutaneous emphysema，and intraoperative hemorrhage，respectively. The records of the operation process and the methods of rescue treatment or symptomatic treatment were reviewed to find out the causes of severe complications and successful experience of rescue or symptomatic treatment. Results From May 1，2021 to April 30，2022，the incidence of severe complications after balloon dilation for tuberculous airway stenosis was only 2. 6% （3/114）in Wuhan Pulmonary Hospital，including 1 case of airway membrane tear，1 case of mediastinal subcutaneous emphysema，and 1 case of postoperative massive bleeding. After symptomatic treatment， all recovered completely. Conclusion The severe complications of balloon dilation for tuberculous trachel-bronchial membrane laceration are mostly seen in patients with extremely severe cicatricial stenosis or central airways occlusion （CAO）requiring recanalization. For severe scar stenosis，scar release before balloon dilation can reduce the incidence of airway membrane tear and mediastinal subcutaneous emphysema. Relevant emergency plans should be made before surgery，appropriate cicatricotomy should be performed before balloon dilation，and active symptomatic treatment after surgery can minimize the impact of serious complications.
    A Case of Central Pontine Myelinolysis Secondary to Perioperative Triphasic Diabetes Insipidus in Children with Craniopharyngioma and Literature Review
    PENG Mengqiao ，JIN Lei
    2023, 51(4):  73-78.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.009
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    Objective To statistically analyze the distribution and clinical significance of different antibody types of Helicobacter pylori（Hp） infection in various stages of gastric mucosa lesions （non-atrophic gastritis， atrophic gastritis， gastric ulcer， intraepithelial neoplasia，and gastric cancer）. Methods 2 081 inpatients admitted to the Third People's Hospital of Hubei Province Affiliated to Jianghan University from 2019 to 2021 were enrolled. The C13 breath test， serological antibody test， gastroscopy， and pathological examination were performed simultaneously. According to the results of gastroscopy and pathological examination，the patients were divided into five groups：non-atrophic gastritis （917 cases），atrophic gastritis （636 cases），gastric ulcer （406 cases），intraepithelial neoplasia（89 cases），and gastric cancer（33 cases）. The relationship between Hp infection with different toxin types and patients' age，gastroscopy，and pathological diagnosis was statistically analyzed. ResultsThe infection rate of Hp in each group from high to low was gastric cancer group，intraepithelial neoplasia group，atrophic gastritis group，gastric ulcer group，and non-atrophic gastritis group，and the difference was statistically significant （P < 0. 05）. A total of 653 cases of type I Hp and 324 cases of type II Hp were detected in 2 081 patients. The positive rate of type I Hp was higher than that of type II Hp in each group，and the difference was statistically significant（P < 0. 05）. There were significant differences in the positive rate of type I Hp and type II Hp among all groups（P < 0. 05）. There were significant differences in cytotoxin-associated protein A（CagA），vacuolar toxin （VacA），and urease（Ure）among all groups（P < 0. 05），and Ure antibody increased with age（≥ 50）. Among 653 patients with type I Hp positive，the CagA + VacA antibody （60. 0%） was the main antibody，which was higher than CagA antibody （36. 2%） and VacA antibody （3. 6%），and the differences were statistically significant （P < 0. 05）. Among 324 patients with type II Hp positive，the positive rate of UreB antibody（64. 8%） in each group was higher than that of UreA + UreB antibody（30. 5%）and UreA antibody （4. 6%），and the difference was statistically significant （P < 0. 05）. Conclusion Hp infection is closely related to gastric mucosal lesions. Type I Hp strain is the main pathogenic strain of gastric diseases，but type II Hp strain infection should not be ignored.
    The Influence of Adverse Pregnancy History on Anxiety and Depression of Pregnant Women
    YU Gongzhi ，CAO Ming ，CHENG Wenna ，LU Huihui ，ZHOU Yan
    2023, 51(4):  79-86.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.010
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    Objective To investigate and analyze the influence of adverse pregnancy history on maternal anxiety and depression. Methods Pregnant women with adverse pregnancy history and normal pregnant women were recruited to complete questionnaires. A self-made basic information questionnaire，self-evaluation of anxiety scale（SAS），and depression self-rating scale（SDS）was used to collect the general data，anxiety scores，and depression scores. Two groups of general information，the anxiety self-assessment scale scores，and the depression self-rating scale scores were compared，the effects of various types of adverse maternal history on maternal anxiety and depression were investigated，and other related factors affecting maternal anxiety and depression were analyzed. Results A total of 235 valid questionnaires were collected， including 69 pregnant women with adverse pregnancy history as the case group，and 166 normal pregnant women as the control group. For the case group，the positive rate of anxiety screening and depression screening was 20. 3% and 37. 7%， respectively. For the control group， the positive rate of anxiety screening and depression screening was 9. 0% and 24. 7%，respectively. The positive rate of anxiety and depression screening in the case group was higher than in the control group，and there was a statistically significant difference （P < 0. 05）. There was no statistically significant difference in the positive rate of anxiety and depression screening among three types of adverse pregnancy history，including induced abortion history，embryo termination history，and infertility history in the first year after marriage. Conclusion Previous adverse pregnancy history is associated with higher anxiety and depression during pregnancy. There was no significant difference in the positive rate of anxiety and depression among three types of adverse pregnancy history：induced abortion history，embryo termination history，and infertility history in the first year after marriage. During pregnancy，more attention should be paid to the emotional state of pregnant women with adverse pregnancy history，timely detection of abnormalities，and corresponding psychological intervention.
    The Complications Risk of Prone Position Ventilation Treating Neonatal Respiratory Distress Syndrome：A Meta-analysis
    FAN Feiyan ，JIANG Chiqiu
    2023, 51(4):  87-96.  doi:10.16389/j.cnki.cn42-1737/n.2023.04.011
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    Objective To discuss the influence of prone position ventilation（PPV） on the complications risk of neonatal respiratory distress syndrome （NRDS）. Methods The two researchers jointly formulated retrieval strategies and inclusion criteria. Relevant clinical controlled trials on the application effect of PPV on NRDS mechanical ventilation in newborns were searched from PubMed，EMBASE，Web of Science，China Biomedical Literature Database，CNKI，Wanfang，and VIP databases，respectively. The literature that met the inclusion criteria was screened out，the quality grade was divided，and valuable information was extracted. Finally，RevMan 5.3 software was used for evidence-based medicine analysis. Results 12 pieces of literature ultimately met the inclusion criteria， covering 1 246 subjects. The Meta-analysis results showed that the risk of pressure ulcers， accidental extubation， ventilator-associated pneumonia， pneumothorax， pulmonary hemorrhage，subcutaneous edema，and intracranial hemorrhage in the supine group was higher than those in the PPV group（P ≤ 0. 05）. There was no significant difference in the risk of artificial airway blockage between the two groups（P > 0. 05）. Conclusion PPV can reduce the risk of pressure ulcers，accidental extubation，ventilator-associated pneumonia， pneumothorax，pulmonary hemorrhage，subcutaneous edema，and intracranial hemorrhage in newborns with NRDS，but does not affect the risk of artificial airway blockage. This study can provide evidence reference for the safety of PPV in neonatology.