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Molecular Characteristics of Cephalosporin-Resistant Neisseria gonorrhoeae Strains in China:A Retrospective Study

International Journal of Dermatology and Venereology 2024年第2期7卷 78-83页

作者： Jin Zhang xiao-Yu Zhu jing-Wei liu Yue-Ping Yin Shao-Chun Chen Reference Laboratory for STD Control Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences&Peking Union Medical CollegeNanjingJiangsu 210042China National Center for STD Control Chinese Center for Disease Control and PreventionNanjingJiangsu 210042China

Objective:An increasing level of antimicrobial resistance to extended-spectrum cephalosporins has been reported,so we conducted this study to investigate the molecular characteristics of cephalosporin resistant Neisseria gonorrhoeae(NG)strains isolated from China Gonococcal Antimicrobial Resistance Surveillance Programme(China-GRSP).Methods:In total,2,038 NG isolates were collected from the China-GRSP between 2015 and *** multiantigen sequence typing(NG-MAST),multilocus sequence typing(MLST),and NG sequence typing for antimicrobial resistance(NG-STAR)were used to determine characteristics and resistant determinants of cephalosporin-resistant *** results are described as ***:Seventy-four(3.6%)cephalosporin-resistant isolates were ***_(ST7363)was the most prevalent MLST among cefixime-resistant(CFX-R)isolates,whereas MLST_(ST7365)(n=8)in was the most prevalent sequence type among ceftriaxone-resistant(CRO-R)***-R strains were mainly associated with penA-X(n=27,44.3%),penA-XIII(n=6,9.8%),penA-XVIII(n=5,8.2%),and CRO-R strains were mainly related to penA-XVIII(n=10,25.6%),penA-43(n=9,23.1%),penA-XIII(n=7,17.9%).Conclusion:The main conclusion of this study is that the predominant cephalosporin-resistant clones in China include locally emerged and imported *** CFX-R and CRO-R strains are primarily related to penA mutations,and their predominant genotypes are *** the increase in international travel,tracking high-risk-resistant clones and identifying outbreaks and their associations with epidemiological characteristics are critical to improve public health.

关键词： gonorrhea resistance cephalosporin cefixime ceftriaxone

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High-sensitivity formaldehyde gas sensor based on Ce-doped urchin-like SnO_(2) nanowires derived from calcination of Sn-MOFs

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Frontiers of Materials Science 2024年第1期18卷 29-43页

作者： Wei xiao Wei Yang Shantang liu Hubei Key Lab of Novel Reactor&Green Chemical Technology School of Chemistry and Environmental EngineeringWuhan Institute of TechnologyWuhan 430073China Hubei Key Laboratory of Wudang Local Chinese Medicine Research Department of ChemistrySchool of Pharmaceutical SciencesHubei University of MedicineShiyan 442000China

Metal-organic frameworks(MOFs)have attracted widespread attention due to their regular structures,multiple material centers,and various *** are always considered as one kind of ideal templates for developing highly sensitive and selective gas *** this study,the advantages of MOFs with the high specific surface area(71.9891 m^(2)·g^(-1))and uniform morphology were fully utilized,and urchin-like SnO_(2) nanowires were obtained by the hydrothermal method followed by the calcination using Sn-MOFs consisting of the ligand of C_(9)H_(6)O_(6)(H_(3)BTC)and Sn/Ce center ions as sacrificial *** unique urchin-like nanowire structure facilitated gas diffusion and adsorption,resulting in superior gas sensitivity.A series of Ce-doped SnO_(2) nanowires with different doping ratios were synthesized,and their gas sensing properties towards formaldehyde were *** resulted Ce-SnO_(2) was revealed to have high sensitivity(201.2 at 250℃),rapid response(4 s),long-term stability,and good repeatability for formaldehyde sensing,and the gas sensing mechanism of Ce-SnO_(2) exposed to formaldehyde was also systematically discussed.

关键词： Ce-SnO_(2) SnO_(2) gas sensor formaldehyde Sn-MOF

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Development of Fixture Layout Optimization for Thin-Walled Parts:A Review

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 15-39页

作者： Changhui liu jing Wang Binghai Zhou Jianbo Yu Ying Zheng Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past ***,few papers systematically review these *** analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods *** process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout *** paper makes a review of the fixture layout for thin-walled parts according to these three ***,two different kinds of optimization objectives are *** usually consider in-plane variations or out-of-plane deformations when designing ***,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based *** common methods are discussed *** that,optimization algorithms are reviewed *** are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic ***,discussions on the current situation are *** research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization ***,a new research point for fixture layout optimization is *** paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.

关键词： Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms

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混合能谱超临界水堆堆芯热工-物理性能分析

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原子能科学技术 2009年第6期43卷 538-542页

作者：刘晓晶程旭上海交通大学核科学与工程学院上海200240

针对一种新型的超临界水堆设计方案——混合能谱超临界水堆(SCWR-M)进行分析。混合能谱超临界水堆包括热谱区和快谱区两部分,分别布置在堆芯的外部与内部。它在继承了热谱与快谱超临界堆芯设计优点的同时,有效地克服了两者的不足。对于... 详细信息

针对一种新型的超临界水堆设计方案——混合能谱超临界水堆(SCWR-M)进行分析。混合能谱超临界水堆包括热谱区和快谱区两部分,分别布置在堆芯的外部与内部。它在继承了热谱与快谱超临界堆芯设计优点的同时,有效地克服了两者的不足。对于热谱区,冷却剂与慢化剂同向流动,大幅降低了燃料包壳的表面温度和组件的机械加工难度;对于快谱区,采用多层燃料组件和较大的栅距棒径比p/d,可得到较高的燃料转换比和较小的冷却剂负反应性系数。本工作采用自主开发的基于子通道分析和三维物理计算的耦合程序,对混合能谱超临界水堆的热工性能和中子物理性能(包括燃耗性能)进行研究。初步的耦合分析结果表明了混合能谱超临界水堆设计方案的可行性。

关键词：超临界水堆混合中子能谱堆芯设计

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超临界水冷堆堆芯子通道稳态热工分析

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核动力工程 2007年第5期28卷 18-21,58页

作者：刘晓晶程旭上海交通大学核科学与工程学院 200240

超临界水冷堆(SCWR)作为6种第四代未来堆型中唯一的水冷堆,冷却剂出口温度可达500℃,具有良好的经济性。本文采用改进的COBRA-IV程序对超临界水冷堆方形组件子通道进行稳态热工分析。对计算结果进行分析可知:减小慢化剂通道中给水质量... 详细信息

超临界水冷堆(SCWR)作为6种第四代未来堆型中唯一的水冷堆,冷却剂出口温度可达500℃,具有良好的经济性。本文采用改进的COBRA-IV程序对超临界水冷堆方形组件子通道进行稳态热工分析。对计算结果进行分析可知:减小慢化剂通道中给水质量流量份额和加大慢化剂通道与相邻子通道之间的热阻,可以降低热管焓升,后者还可以得到较好的慢化效果。通过热通道的传热恶化分析发现,超临界水冷堆的设计不能避免传热恶化,必须精确计算传热恶化条件下的包壳温度才能确定包壳能否保证其完整性。

关键词：超临界水冷堆子通道组件设计传热恶化

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Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 213-227页

作者： Changhui liu jing Wang Ying Zheng Ke Jin Jianbo Yu Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

There are lots of researches on fixture layout optimization for large thin-walled *** researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of ***,how to determine the number of fixtures is *** most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra ***,this paper constructs an optimization model to minimize the number of *** constraints are set in the optimization model to ensure that the part deformation is within the surface profile *** addition,the assembly gap between two parts is also *** conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia *** the algorithm,particles are encoded according to the fixture *** dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization ***,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality *** research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.

关键词： Assembly quality Large thin-walled parts Fixture layout PSO FEM

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From molecule to cell:the expanding frontiers of plant immunity

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Journal of Genetics and Genomics 2024年第7期51卷 680-690页

作者： Lei Li jing liu Jian-Min Zhou Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China

In recent years,the field of plant immunity has witnessed remarkable *** the co-evolution between plants and pathogens,plants have developed a wealth of intricate defense mechanisms to safeguard their *** identified immune receptors have added unexpected complexity to the surface and intracellular sensor networks,enriching our understanding of the ongoing plant–pathogen *** the molecular mechanisms of resistosome shapes our understanding of these mysterious molecules in plant ***,technological innovations are expanding the horizon of the plant–pathogen battlefield into spatial and temporal *** the development provides new opportunities for untangling the complex realm of plant immunity,challenges remain in uncovering plant immunity across spatiotemporal dimensions from both molecular and cellular levels.

关键词： Plant immunity Calcium Spatiotemporal Biomolecular condensate Immune receptor Resistosome

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Friction moment calculation method for tapered roller bearings under combined loads

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Science China(Technological Sciences) 2024年第8期67卷 2565-2578页

作者： LI XinBin liu jing HUANG SuHe PAN Guang School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi’an 710072China System Engineering Research Institute Beijing 100094China

Tapered roller bearings(TRBs) can withstand axial loads, radial loads, and overturning moments. The performance, safety, and efficiency of rotating machinery are directly influenced by the friction moments within the TRBs. However, most current research has relied on empirical formulas that focus on axial loads. Additionally, the friction coefficient between the rollers and the inner ring rib has been defined using simple empirical methods. In actual applications, the loads on TRBs are not purely axial or radial, and simple empirical friction coefficients do not adequately account for the varying lubrication conditions. To address this challenge, this study proposes an improved method for calculating the friction moments of TRB under combined axial and radial loads. This study employs a calculation method for sliding friction coefficients that can model dry, boundary, elastohydrodynamic, and mixed lubrication conditions. To demonstrate the advantages of the proposed method, the friction moments obtained using the existing and proposed methods are compared. Additionally, the influence of TRB structural parameters on the friction moment is discussed. An experimental study is conducted to validate the effectiveness of the proposed method. The findings provide valuable insights for designing TRB structural parameters to minimize friction moments.

关键词： tapered roller bearing friction moment structural parameters combined loads

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Lorentz violation induces isospectrality breaking in Einstein-bumblebee gravity theory

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 87-96页

作者： Wentao liu Xiongjun Fang Jiliang jing Jieci Wang Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

In this study,we investigate the quasinormal modes(QNMs)of a Lorentz-violating spacetime,factoring in a cosmological constant,within the framework of Einstein-bumblebee *** findings reveal that the interaction of spacetime with an anisotropic bumblebee field imparts distinct contributions to the axial and polar sectors of the vector *** subsequently breaks the isospectrality typically observed in vector *** evidence strongly indicates isospectral breaking in the vector modes of Einstein-bumblebee black holes:a pronounced breakage in the real part of the frequencies,while the imaginary component seems less *** isospectral breaking indicates the existence of two different waveforms in the Ringdown phase of the black hole,which provides a potential signal of quantum gravity observable in current experiments.

关键词： Lorentz-violating isospectral breaking quasinormal modes

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Collision-free parking recommendation based on multi-agent reinforcement learning in vehicular crowdsensing

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Digital Communications and Networks 2024年第3期10卷 609-619页

作者： Xin Li Xinghua Lei Xiuwen liu Hang xiao College of Computer Science and Technology China University of Petroleum(East China)QingDao266580China

The recent proliferation of Fifth-Generation(5G)networks and Sixth-Generation(6G)networks has given rise to Vehicular Crowd Sensing(VCS)systems which solve parking collisions by effectively incentivizing vehicle ***,instead of being an isolated module,the incentive mechanism usually interacts with other *** on this,we capture this synergy and propose a Collision-free Parking Recommendation(CPR),a novel VCS system framework that integrates an incentive mechanism,a non-cooperative VCS game,and a multi-agent reinforcement learning algorithm,to derive an optimal parking strategy in real ***,we utilize an LSTM method to predict parking areas roughly for recommendations *** incentive mechanism is designed to motivate vehicle participation by considering dynamically priced parking tasks and social network *** order to cope with stochastic parking collisions,its non-cooperative VCS game further analyzes the uncertain interactions between vehicles in parking *** its multi-agent reinforcement learning algorithm models the VCS campaign as a multi-agent Markov decision process that not only derives the optimal collision-free parking strategy for each vehicle independently,but also proves that the optimal parking strategy for each vehicle is ***,numerical results demonstrate that CPR can accomplish parking tasks at a 99.7%accuracy compared with other baselines,efficiently recommending parking spaces.

关键词： Incentive mechanism Non-cooperative VCS game Multi-agent reinforcement learning Collision-free parking strategy Vehicular crowdsensing

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