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石油科学：英文版 2022年第3期19卷 1250-1261页

作者： yun-Tao Li xiao-Ning he Jian Shuai College of Safety and Ocean Engineering China University of PetroleumBeijingChina

Buried natural gas pipelines are vulnerable to external corrosion because they are encased in a soil environment for a long time.Identifying the causes of external corrosion and taking specific maintenance measures is essential.In this work,a risk analysis and maintenance decision-making model for natural gas pipelines with external corrosion is proposed based on a Bayesian network.A fault tree model is first employed to identify the causes of external corrosion.The Bayesian network for risk analysis is determined accordingly.The maintenance strategies are then inserted into the Bayesian network to show a reduction of the risk.The costs of maintenance strategies and the reduced risk after maintenance are combined in an optimization function to build a decision-making model.Because of the limitations of historical data,some of the parameters in the Bayesian network are obtained from a probabilistic estimation model,which combines expert experience and fuzzy set theory.Finally,a case study is carried out to verify the feasibility of the maintenance decision model.This indicates that the method proposed in this work can be used to provide effective maintenance schemes for different pipeline external corrosion scenarios and to reduce the possible losses caused by external corrosion.

关键词： Natural gas pipelines External corrosion Risk analysis Maintenance decision making Bayesian network

Flow control characteristics of the digital and mechanical redundancy control electric modulation valve

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第8期23卷 599-609页

作者： he LIU Bin ZHAO Bo WANG Long QUAN yun-xiao HAO yun-wei LI Key Laboratory of Advanced Transducers and Intlligent Control System of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024China Deparment of Electrical and Computer Engineering University of AlbertaEdmonton ABT6G1H9Canada

The electrical modulation valve can provide proportional output valve element displacement,flow,or pressure according to a continuously changing input electrical signal.It is the core component of electro-hydraulic proportional control technology.To remove the influence of pressure difference changes on the output flow,the traditional scheme is to use a pressure compensation valve,which increases the difficulty of both manufacturing and maintaining the valve.To solve this problem,a method of digital and mechanical redundancy control flow is proposed.Pressure sensors are installed at the inlet and outlet of the valve,and the controller adjusts the displacement of the valve element according to the pressure difference between the valve ports to realize high-precision control of the flow.A pressure compensation valve is installed in front of the valve,and a three-way solenoid valve is used to control the working of the compensation valve.In the case of sensor failure,the valve is switched to the mechanical compensation differential pressure mode,to control the flow and to achieve redundancy control.The system security is thereby improved.The feasibility of this scheme is verified through simulation and tests.The results show that,both for digital compensation and mechanical compensation,the output flow can be kept constant when the pressure difference changes,and the system has good static and dynamic characteristics.The principle can be applied to the displacement-flow feedback type electrical modulation valve,and can realize accurate control of the flow of the pilot valve and,finally,accurate control of the flow in the main valve.

关键词： Electrical modulation valve Control characteristics Co-simulation Redundancy control

Clinical significance of serum miR-129-5p in patients with diabetes mellitus presenting macrovascular complications

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World Journal of Diabetes 2021年第8期12卷 1282-1291页

作者： Xiao-Yun He Chun-Lin Ou Department of Pathology Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Endocrinology Affiliated Hospital of Guilin Medical UniversityGuilin 541001Guangxi Zhuang Autonomous RegionChina

BACKGROUND Diabetic macrovascular complications(DMCs)are the most common complications encountered during the course of diabetes mellitus(DM)with extremely high mortality rates.Therefore,there is an urgent need to identify specific and sensitive biomarkers for the early diagnosis of DMCs.AIM To investigate the expression and significance of serum miR-129-5p in patients with DM and macrovascular complications.METHODS Serum samples were collected from 36 healthy controls,58 patients with DM presenting no macrovascular complications,and 62 patients with DMCs.The expression of miR-129-5p was detected using quantitative real-time polymerase chain reaction.Pearson’s correlation assay was performed to analyze the correlation between serum miR-129-5p levels and clinical indicators.Receiver operator characteristic(ROC)analysis was conducted to analyze the diagnostic value of serum miR-129-5p in patients with DM or DMCs.RESULTS There was a 4.378-fold and 7.369-fold increase in serum miR-129-5p expression in the DM(5.346±0.405)and DMCs(8.998±0.631)groups,respectively(Phe control group(1.221±0.090).In addition,the expression of serum miR-129-5p in patients with DMCs was higher than that in patients with DM,revealing a 1.683-fold increase(Phemoglobin(HbA1c)in patients with DMCs(Phe area under the ROC curve(AUC)of miR-129-5p as a serum marker was 0.964(95%confidence interval[CI]:0.930-0.997,Phealthy controls,whereas the AUC of miR-129-5p as a serum marker was 0.979(95%CI:0.959-0.999,Phealthy controls.CONCLUSION Elevated serum miR-129-5p expression levels correlate with the development of DMCs and can be utilized as a novel early diagnostic biomarker for DM combined with macrovascular complications.

关键词： Diabetes mellitus Diabetic macrovascular complications MircoRNA Diagnosis Therapy

Activation of Carbon Dioxide by Gas-phase Metal Species

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1385-1403页

作者： LIU yun-Zhu LI xiao-Na he Sheng-Gui State Key Laboratory for Structural Chemistty of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Molecular Sciences and CAS Research/Educatiou Center of Excellence in Molecular Sciences Beijing 100190China

Catalytic conversion of carbon dioxide(CO_(2)) into value-added chemicals is an important and active field in both of the condensed-phase and gas-phase studies. This mini-review summarizes a variety of experimentally identified reactions in the activation and transformation of CO_(2) by metal species in the gas phase. The use of advanced mass spectrometric instrumentation in conjunction with quantum chemistry calculations can uncover the mechanistic details and determine the vital factors that control the activation of CO_(2). This review focuses mainly on three topics: the activation of CO_(2) by(1) bare metal ions and metal oxide species,(2) metal hydrides, and(3) other gas-phase metal species. Emphasis is placed on the latest advances in the hydrogenation of CO_(2) mediated with metal hydrides. A potential prospect toward the future effort in the activation and transformation of CO_(2) in gas phase has also been discussed.

关键词： carbon dioxide activation gas-phase metal species mass spectrometry quantum chemistry calculations

Application of extended criteria donor grafts in liver transplantation for acute-on-chronic liver failure:A retrospective cohort study

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World Journal of Gastroenterology 2023年第41期29卷 5630-5640页

作者： Jin-Long Gong Jia Yu Tie-Long Wang xiao-Shun he yun-Hua Tang xiao-Feng Zhu Department of hepatobiliary Surgery Hunan Provincial People's HospitalThe First Affiliated Hospital of Hunan Normal UniversityChangsha 410005Hunan ProvinceChina Organ Transplant Center The First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina Department of Gastroenterology Surgery The First Affiliated Hospital of University of South ChinaHengyang 421005Hunan ProvinceChina

BACKGROUND There is no consensus on the usage of extended criteria donor(ECD)grafts in liver transplantation(LT)for acute-on-chronic liver failure(ACLF)patients.AIM To summarize the experience of using ECD livers in ACLF-LT.METHODS A retrospective cohort study was conducted,enrolling patients who underwent LT at the First Affiliated Hospital of Sun Yat-Sen University from January 2015 to November 2021.The patients were divided into ECD and non-ECD groups for analysis.RESULTS A total of 145 recipients were enrolled in this study,of which ECD and non-ECD recipients accounted for 53.8%and 46.2%,respectively.Donation after cardiac death(DCD)recipients accounted for the minority compared with donation after brain death(DBD)recipients(16.6%vs 83.4%).Neither overall survival nor graft survival significantly differed between ECD and non-ECD and DCD and DBD recipients.ECD grafts were associated with a significantly higher incidence of early allograft dysfunction(EAD)than non-ECD grafts(67.9%vs 41.8%,P=0.002).Postoperative outcomes between DCD and DBD recipients were comparable(P>0.05).ECD graft(P=0.009),anhepatic phase(P=0.034)and recipient gamma glutamyltransferase(P=0.016)were independent risk factors for EAD.Recipient preoperative number of extrahepatic organ failures>2(P=0.015)and intraoperative blood loss(P=0.000)were independent predictors of poor post-LT survival.CONCLUSION Although related to a higher risk of EAD,ECD grafts can be safely used in ACLF-LT.The main factors affecting post-LT survival in ACLF patients are their own severe preoperative disease and intraoperative blood loss.

关键词： Extended criteria donor Acute-on-chronic liver failure Liver transplantation

Poly(arylene ether nitrile)Dielectric Film Modified by Bi_(2)S_(3)/rGO-CN Fillers for High Temperature Resistant Electronics Fields

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Chinese Journal of Polymer Science 2022年第11期40卷 1441-1450页

作者： Li-Fen Tong Liang he Chen-Hao Zhan yun-Qing Xia xiao-Bo Liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu610054China Sichuan Province Engineering Technology Research Center of Novel CN Polymeric Materials Chengdu610054China

High-quality film capacitors are widely used in many fields such as new energy vehicles,electronic communications,etc.,due to their advantages in wide frequency response and low dielectric loss.The dielectric film is a crucial part of the film capacitor,and its properties have an important impact on the performance and use conditions of the film capacitor.In this work,a novel high-temperature-resistant dielectric film was prepared.Firstly,the Bi_(2)S_(3)/rGO-CN fillers were prepared by hydrothermal method combined with cyanation treatment,and then added to the poly(arylene ether nitrile)(PEN)matrix to prepare the dielectric film materials(PEN/Bi_(2)S_(3)/rGO-CN).After high temperature treatment,the fillers Bi_(2)S_(3)/rGO-CN reacted with the PEN matrix,and the composites materials transformed into a thermosetting hybrid film(PEN-Bi_(2)S_(3)/rGO)with gel content of 97.88%.The prepared hybrid dielectric films did not decompose significantly before 400℃,and showed a glass transition temperature(Tg)of up to 252.4℃,which could increase the effective use temperature of the materials.Compared with the composite films without heat treatment,they exhibit better mechanical properties,with further improvement in tensile strength and elastic modulus,and a decrease in elongation at break.The dielectric constant of the hybrid films can be up to 6.8 while the dielectric loss is only about 0.02 at 1 kHz.Moreover,the hybrid films showed excellent dielectric stability during temperature changes,and remain relatively stable before 250℃,which is suitable as a high-temperature-resistant high-dielectric material and is more advantageous for practical applications.

关键词： Poly(arylene ether nitrile) Bismuth sulfide Graphene oxide High-temperature-resistant Dielectric properties

Clostridium perfringens gas gangrene caused by closed abdominal injury: A case report and review of the literature

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World Journal of Clinical Cases 2023年第4期11卷 852-858页

作者： he-yun Li Zhi-Xiang Wang Jian-Chun Wang xiao-Di Zhang Department of Intensive Care Unit Shaanxi Nuclear Industry 215 HospitalXianyang 712000Shaanxi ProvinceChina Department of General Surgery Shaanxi Nuclear Industry 215 HospitalXianyang 712000Shaanxi ProvinceChina Department of healthcare-associate Infection Management Shaanxi Nuclear Industry 215 HospitalXianyang 712000Shaanxi ProvinceChina

BACKGROUND Abdominal Clostridium perfringens(C. perfringens) gas gangrene is a rare infection that has been described in the literature as most frequently occurring in postoperative patients with open trauma. Intra-abdominal gas gangrene caused by C.perfringens infection after closed abdominal injury is extremely rare, difficult to diagnose, and progresses rapidly with high mortality risk. here, we report a case of C. perfringens infection caused by closed abdominal injury.CASE SUMMARY A 54-year-old male suffered multiple intestinal tears and necrosis after sustaining an injury caused by falling from a high height. These injuries and the subsequent necrosis resulted in intra-abdominal C. perfringens infection. In the first operation,we removed the necrotic intestinal segment, kept the abdomen open and covered the intestine with a Bogota bag. A vacuum sealing drainage system was used to cover the outer layer of the Bogota bag, and the drainage was flushed under negative pressure. The patient was transferred to the intensive care unit for supportive care and empirical antibiotic treatment. The antibiotics were not changed until the results of bacterial culture and drug susceptibility testing were obtained.Two consecutive operations were then performed due to secondary intestinal necrosis. After three definitive operations, the patient successfully survived the perioperative period. Unfortunately, he died of complications related to GuillainBarre syndrome 75 d after the first surgery. This paper presents this case of intraabdominal gas gangrene infection and analyzes the diagnosis and treatment based on a review of current literature.CONCLUSION When the intestines rupture leading to contamination of the abdominal cavity by intestinal contents, C. perfringens bacteria normally present in the intestinal tract may proliferate in large numbers and lead to intra-abdominal infection. Prompt surgical intervention, adequate drainage,appropriate antibiotic therapy, and intensive supportive care comprise the most effective tr

关键词： Clostridium perfringens Intra-abdominal infection Gas gangrene Open abdomen Case report

The use of melittin to enhance transgene expression mediated by recombinant adeno-associated virus serotype 2 vectors both in vitro and in vivo

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Journal of Integrative Medicine 2023年第1期21卷 106-116页

作者： Yi-lin Xie Ji-yao Wang yun he xiao-min Yu Qing-yun Zheng Chen Ling Xi-lin Feng Li-qing Zhu State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology(Ministry of Education) School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200438China Department of Clinical Laboratory the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province Wenzhou 325000Zhejiang ProvinceChina Yantai Fuheng Biological Technology Co. Ltd.Yantai 264006Shandong ProvinceChin

Objective: Melittin, a cell-penetrating peptide, improves the efficiency of many non-viral gene delivery vectors, yet its application in viral vectors has not been well studied. The non-pathogenic recombinant adeno-associated virus(rAAV) vector is an ideal in vivo gene delivery vector. However, its full potential will only be achieved after improvement of its transduction efficiency. To improve the transduction efficiency of rAAV2 vectors, we attempted to develop a melittin-based r AAV2 vector delivery strategy.Methods: The melittin peptide was inserted into the rAAV2 capsid either in the loop Ⅷ of all viral proteins(VPs) or at the N terminus of VP2. Various r AAV2-gfp or-fluc vectors were subjected to quantitative real-time polymerase chain reaction and Western blot assays to determine their titers and integrity of capsid proteins, respectively. Alternatively, the vectors based on wild-type capsid were pre-incubated with melittin, followed by transduction of cultured cells or tail vein administration of the mixture to C57BL/6 and BALB/c nude mice. In vivo bioluminescence imaging was performed to evaluate the transgene expression.Results: rAAV2 vectors with melittin peptide inserted in the loop Ⅷ of VPs had low transduction efficiency, probably due to dramatically reduced ability to bind to the target cells. Fusing the melittin peptide at the N-terminus of VP2 produced vectors without the VP2 subunit. Interestingly, among the commonly used rAAV vectors, pre-incubation of r AAV2 and rAAV6 vectors with melittin significantly enhanced their transduction efficiency in heK293 and Huh7 cells in vitro. Melittin also had the ability to increase the rAAV2-mediated transgene expression in mouse liver in vivo. Mechanistically, melittin did not change the vector-receptor interaction. Moreover, cell counting kit-8 assays of cultured cells and serum transaminase levels indicated melittin had little cytotoxicity.Conclusion: Pre-incubation with melittin, but not insertion of melittin into the rAAV2 capsid, significantly enhanced

关键词： TAAV Melittin Capsid engineering Co-administration Transduction efficiency

前馈多源信息下异构动力学卡车队列协同控制系统

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交通运输工程学报 2023年第1期23卷 256-266页

作者：吴超仲杨鑫炜贺宜 LU xiao-yun 武汉理工大学智能交通系统研究中心湖北武汉430063 加利福尼亚大学伯克利分校加利福尼亚先进交通技术研究中心加利福尼亚伯克利CA 94804

针对目前卡车队列动力学异构性所导致的系统弦稳定性、内部稳定性以及队列耦合性降低的问题,提出了一种异构协同自适应巡航系统控制器设计方法,建立了基于前馈多源信息的异构动力学卡车队列闭环耦合系统;考虑由异构车型所构成的卡车队... 详细信息

针对目前卡车队列动力学异构性所导致的系统弦稳定性、内部稳定性以及队列耦合性降低的问题,提出了一种异构协同自适应巡航系统控制器设计方法,建立了基于前馈多源信息的异构动力学卡车队列闭环耦合系统;考虑由异构车型所构成的卡车队列存在发动机执行器的饱和态异构问题,建立了发动机饱和性和状态约束条件;在上层协同控制器的基础上,建立了一种非线性下层异构发动机扭矩输出控制模型,用于控制车辆动力学仿真软件TruckSim中的真实车辆模型;建立了基于三维燃油特性图的车辆能耗模型,用于计算实时车辆油耗和节能性分析;通过频域分析法,结合已知异构动力学参数量化标定了协同自适应巡航系统控制器的增益,确保系统满足弦稳定条件。分析结果表明:相比同构动力学控制器,异构协同自适应巡航系统控制器可以确保距离误差在-0.01~0.15 m内,优于同构控制器作用下的-0.3~0.5 m,且当领航车进入匀速行驶状态时,跟随车辆能立刻收敛至相同的行驶状态,收敛性能优于同构协同自适应巡航控制系统;卡车队列节油率最大可达8.15%,随着车头时距减小至0.5 s,平均节油率最大可达8.10%。由此可见,多源前馈信息异构控制系统能有效降低车辆的状态误差传递,设计的前馈多源信息下异构动力学卡车队列协同控制系统能提升队列的弦稳定性,也能保证系统的燃油经济性。

关键词：汽车工程卡车队列协同控制系统异构动力学发动机饱和态约束弦稳定性

Effect of CacO_(3) on volatilization of self-reduced zinc from blast furnace dust

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Journal of Iron and Steel Research(International) 2022年第9期29卷 1404-1411页

作者： Wei-an Wang xiao-ming Li-yun he Hao-dong Xi Jian-li Wang Guo-xing Qiu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina

To solve the problem of low reduction extraction rate of zinc from blast furnace dust,the effects of CacO3 addition,reduction temperature,and reduction time on self-reduction zinc extraction were studied through high-temperature reduction experiment,and the mechanism of how CaCO_(3) addition promotes zinc ferrite reduction was analyzed.The zinc removal rate can reach 98.82%when the blast furnace dust is reduced at 1000℃ for 25 min by adding 10 mass%CaCO_(3).At low temperature,CaCO_(3) can enhance the reduction and decomposition of ZnFe_(2)O_(4)(which is difficult to reduce)into ZnO and low-valent iron oxides.After CaCO_(3) is decomposed at high temperature,CO_(2) is produced to undergo gasification reaction with carbon in blast furnace dust,and co is generated to provide more reducing agents for the whole reduction system.CaO generated by decomposition can also catalyze the gasification reaction of carbon,thus improving the removal rate of zinc in the reduction process of dust.

关键词： Blast furnace dust Self reducing zinc extraction Calcium carbonate Zinc ferrite