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核苷(酸)类似物治疗慢性乙型肝炎患者HBV逆转录酶区变异的研究

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实验与检验医学 2017年第4期35卷 466-474页

作者：李健曾文兴方颖慧曾小平南昌大学基础医学院免疫学教研室江西南昌330006 宜春市人民医院检验科江西宜春336000

目的分析核苷(酸)类似物治疗的慢性乙型肝炎患者HBV逆转录酶区耐药相关变异位点、变异位点组合模式、HBV DNA水平和HBeAg等特征,为临床应用核苷(酸)类似物抗乙肝病毒治疗提供参考。方法纳入研究的141例慢性乙型肝炎患者,使用NAs治疗的10... 详细信息

目的分析核苷(酸)类似物治疗的慢性乙型肝炎患者HBV逆转录酶区耐药相关变异位点、变异位点组合模式、HBV DNA水平和HBeAg等特征,为临床应用核苷(酸)类似物抗乙肝病毒治疗提供参考。方法纳入研究的141例慢性乙型肝炎患者,使用NAs治疗的107例为治疗组,未使用药物抗病毒治疗的34例为对照组。采用线性探针反向杂交法(PCRRLP)检测HBV逆转录酶区耐药相关变异位点,实时荧光定量PCR法检测乙型肝炎病毒DNA水平,酶联免疫吸附试验检测乙肝免疫标记物,并对耐药相关变异的特点和研究病例的临床资料进行统计学分析。结果核苷(酸)类似物治疗效果不佳组耐药相关变异检出率(82.5%)明显高于未治疗的对照组(5.9%)和抗病毒治疗有效组(有效组10例未检出耐药相关变异)(P<0.01)。97例核苷(酸)类似物抗病毒效果不佳的病例中80例检出140个耐药相关变异位点,包括rtM204I 45个、rtM204V 32个、rtA181V 28个、rtL180M 25个、rtN236T 10个;变异位点组合模式主要有:rtL180M+rtM204I、rtM204V、rtM204I+rtM204V、rtA181V+rtM204V、rtM204I、rtA181V+rtN236T等;51个对NAs应答不佳病例耐药变异检出率70.59%,46个病毒学突破病例耐药变异检出率95.65%,差异明显(P<0.01)。NAs单药治疗病例早于多药治疗病例检出耐药相关位点(P<0.01);NAs治疗时间越长,耐药变异检出率越高(P<0.01);病例HBV-DNA水平等级越高,耐药变异检出率也越高(P<0.01)。结论⑴NAs治疗慢性乙型肝炎可导致HBV逆转录酶区变异,NAs抗乙型肝炎病毒效果不佳与HBV逆转录酶区变异密切相关;⑵不同NAs药物导致慢性乙肝患者HBV逆转录酶区变异位点、变异模式特点不同;⑶NAs治疗慢性乙型肝炎的用药种类与方式、治疗时长,患者HBV-DNA水平等对HBV逆转录酶区发生耐药变异均可能产生重要影响。提示在NAs治疗前、治疗过程合适时间点检测NAs耐药相关变异位点和HBV DNA水平,可为临床慢性乙型肝炎的抗病毒治疗提供重要参考。

关键词：核苷(酸)类似物慢性乙型肝炎耐药 HBV逆转录酶区基因变异

Synergy enhancement of Co single atoms and asymmetric subnanoclusters for Fenton-like activation

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Nano Research 2024年第9期17卷 7935-7944页

作者： Ming Ma Zhiyi Sun Ziwei Deng Xiang Li fang Zhang wenxing Chen School of Materials Key Laboratory of Cluster Science Ministry of EducationBeijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsAdvanced Technologies Research Institute(Jinan)Advanced Research Institute of Multidisciplinary ScienceSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Energy and Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Analysis and Testing Center Beijing Institute of TechnologyBeijing Institute of TechnologyBeijing 100081China

As a new water treatment technology,Fenton-like reaction has great *** this study,we successfully prepared an excellent Fenton-like catalyst,which is composed of cobalt monoatoms and asymmetric subnanoclusters(labeled CoSA/Clu-C_(2)N),and exhibits excellent peroxymonosulfate(PMS)activation *** directly comparing the catalytic properties of CoSA-C_(2)N and CoSA/Clu-C_(2)N,the synergistic effects of coasymmetric Co subclusters and Co atoms on the activation of PMS and degradation of organic micropollutants were *** results showed that CoSA/Clu-C_(2)N had higher degradation rates of carbamazepine(CBZ),antipyrine(AT)and chlorobenzoic acid(CA)when combined with active oxidant *** cyclic frequency of CBZ was 5.4 min^(-1),which was twice as high as the catalytic constant of CoSA-C_(2)N(2.4 min^(-1)).The results show that CoSA/Clu-C_(2)N cobalt subnanoclusters and cobalt single atom can synergistically improve the catalytic performance of activated PMS oxidation of micropollutants in *** addition,electron paramagnetic resonance(EPR)technology has proved that the introduction of Co subnano clusters in CoSA/Clu-C_(2)N is conducive to the production of singlet oxygen(1O_(2)),thereby improving the efficiency of pollutant *** work lays a solid foundation for the future design of advanced multifunctional catalysts by carefully regulating and combining monmetallic atoms and metal subnanoclusters.

关键词： carbamazepine Fenton-like reaction Co single atoms asymmetrical sub-nanoclusters peroxymonosulfate synergy enhancement

Highly efficient hydrogen production from methanol by single nickel atoms anchored on defective boron nitride nanosheet

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Nano Research 2023年第7期16卷 8800-8808页

作者： Shengshu Yang fang Zhang Haifa Qiu Ming Yang Fengjuan Qin Hao Tang wenxing Chen Zhengang Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China National Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101408China Analytical and Testing Center Beijing Institute of TechnologyBeijing 100081China Department of Applied Physics the Hong Kong Polytechnic UniversityHong Kong 999077China Energy&Catalysis Center School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China

Exploiting inexpensive and effective nickel-based catalysts that produce hydrogen from liquid organic hydrogen carriers(LOHCs)is crucial to alleviating the global energy and environmental *** this study,we report a rational strategy that can realize atomically dispersed Ni atoms anchored on vacancy-abundant boron nitride nanosheets(Ni1/h-BNNS)with high specific surface area(up to 622 m^(2)·g^(-1))and abundant hydroxyl groups for high efficient hydrogen *** dehydrogenation results show an excellent hydrogen production performance catalyzed by this Ni1/h-BNNS,as evidenced by a remarkably high H_(2) yield rate(1684.23 mol·mol_(Ni)^(-1)·h^(-1)),nearly 100%selectivity toward hydrogen and CO,and high anti-coking *** functional theory(DFT)calculations reveal that the outstanding catalytic performance of Ni1/h-BNNS primarily originates from the unique coordinated environment of atomically dispersed Ni(Ni-B_(2)O_(2))and the synergistic interaction between Ni single atoms and the h-BNNS ***,the coordinated O atoms play a decisive role in promoting the activity of Ni,and the neighboring B sites significantly decrease the energy barriers for the adsorption of key intermediates of methanol *** study offers a novel strategy for developing high-performance and stable single-atom Ni catalysts by precisely controlling single-atom sites on h-BN support for sustainable hydrogen production.

关键词： single-atom catalyst coordination environment boron nitride hydrogen production liquid organic hydrogen carriers

Fertilization practices affect biological nitrogen fixation by modulating diazotrophic communities in an acidic soil in southern China

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Pedosphere 2023年第2期33卷 301-311页

作者： Long GUO Chao WANG Manman ZHENG wenxing LI Zejiang CAI Boren WANG Juan CHEN Ren fang SHEN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Qiyang Red Soil Experimental Station Chinese Academy of Agricultural SciencesQiyang 426182(China) Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education Hohai UniversityNanjing 210098(China)

Biological nitrogen(N)fixation(BNF)driven by diazotrophs is an important pathway for N input in agricultural ***,free-living BNF and its associated diazotrophic communities under different fertilization practices in acidic soils are poorly ***,we conducted a long-term(29 years)fertilization experiment to explore how fertilization affected free-living BNF via changing biotic and abiotic *** fertilization treatments included an unfertilized control(CK),chemical N,phosphorus(P),and potassium(K)fertilizers(NPK),NPK plus lime(NPKL),NPK plus straw(NPKS),NPK plus straw and lime(NPKSL),and NPK plus manure(NPKM).Compared with CK(1.51 nmol C_(2)H_(2)g^(-1)d^(-1)),BNF rate was significantly(P<0.05)higher in NPKM(1.99 nmol C_(2)H_(2)g^(-1)d^(-1))but lower in NPK(0.55 nmol C_(2)H_(2)g^(-1)d^(-1)),NPKL(0.61 nmol C_(2)H_(2)g^(-1)d^(-1)),and NPKS(0.69nmol C_(2)H_(2)g^(-1)d^(-1)).Similarly,chemical fertilization treatments without manure reduced the gene abundance(0.71×10^(8)-1.18×10^(8)copies g^(-1))andα-diversity(Shannon index,1.11-2.43)of diazotrophic communities,whereas the treatment with manure had a positive effect on diazotrophic abundance(3.23×10^(8)copies g^(-1))and Shannon index(3.36).Non-parametric multivariate analysis of variance(PERMANOVA)suggested that manure application(R^(2)=0.212,P=0.001)had a stronger influence on diazotrophic community composition than the addition of lime(R^(2)=0.115,P=0.019)or straw(R^(2)=0.064,P=0.161).Random forest modeling revealed that BNF rates can be significantly(P<0.05)explained by soil pH(9.9%),diazotrophic community attributes(composition,8.5%;Chao 1 index,8.1%;abundance,6.0%;Shannon index,5.7%),and soil total carbon(5.1%).Partial least squares path modeling(PLS-PM)suggested that the diazotrophic community attributes and soil properties mainly provided direct and indirect contributions to the variations in BNF rates,*** dominant genera,Pelomonas,Azospirillum,and Dechloromonas,were positiv

关键词： chemical fertilizer community composition free-living N fixation long-term fertilization practices manure application soil pH

Electrocatalytic acidic oxygen evolution reaction:From nanocrystals to single atoms

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Aggregate 2021年第4期2卷 100-121页

作者： Nadia Ismail Fengjuan Qin Chaohe fang Dan Liu Bihan Liu Xiangyu Liu Zi-long Wu Zhuo Chen wenxing Chen Energy&Catalysis Center Department of Materials Physics and ChemistrySchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijingPeople’s Republic of China CNPC Research Institute of Petroleum Exploration&Development BeijingPeople’s Republic of China

Hydrogen is the most preferred choice as an energy source to replace the nonrenewable energy resources such as fossil fuels due to its beneficial features of abundance,ecofriendly,and outstanding gravimetric energy *** water through a proton exchange membrane(PEM)electrolyzer is a well-known method of hydrogen *** the major impediment is the sluggish kinetics of oxygen evolution reaction(OER).Currently,scientists are struggling to build out an acid-stable electrocatalyst for OER with low overpotential and excellent *** this review,the reaction mechanism and characterization parameters of OER are introduced,and then the improvement method of metal nanocatalysts(noble metal catalysts and noble metal-free catalysts)in acidic media is ***,the application of single-atom catalysts in acidic OER is summarized,which is current researching *** the same time,we also briefly introduced the cluster phenomenon,which is easy to occur in the preparation of single-atom *** importantly,we summarized the in situ characterization methods such as in situ X-ray absorption spectroscopy,in situ X-ray photoelectron spectroscopy,and so forth,which are conducive to further understanding of OER reaction intermediates and active ***,we put forward some opinions on the development of acidic OER.

关键词： acidic media in situ characterization nanocatalysis oxygen evolution reaction single-atom catalysis

Cooperative optimal mid-course guidance laws with parameter optimization

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Cooperative optimal mid-course guidance laws with parameter ...

第三十九届中国控制会议

作者： Zihao Wu Yangwang fang wenxing Fu Collage of Aerospace Northwestern Polytechnical University Collage of Unmanned Systems Technology Northwestern Polytechnical University

At present, there is no clear way to select the cooperative term coefficients in the cooperative guidance law based on the biased proportional guidance architecture, which is not conducive to project implementation. In this paper, considering the group cost function, an optimization method is proposed to solve the cooperative term coefficients of a cooperative guidance ***, the structure of cooperative mid-course guidance is introduced in three-dimensional inertial coordinate system. Secondly, the optimization method of the cooperative term coefficient is given and analyzed. Finally, numerical simulation results are given to illustrate the effectiveness of the proposed optimization method.

关键词： Cooperative mid-course guidance laws parameter optimization maneuvering target

UAV Path Planning Based on Shuffled Frog-Leaping Algorithm and Dubins Path

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UAV Path Planning Based on Shuffled Frog-Leaping Algorithm a...

第三十九届中国控制会议

作者： Xinfang Li Yangwang fang wenxing Fu Northwestern Polytechnical University

In this paper, a novel path planning algorithm for the fixed-wing UAV based on shuffled frog-leaping algorithm（SFLA） and Dubins path is proposed. First, the Dubins path planning is transformed into a discrete combinatorial optimization problem. Then the SFLA is used to search the optimal Dubins path, so that the generated flight path directly satisfies the minimum turning radius constraint of UAV. In order to perfectly combine the SFLA and the Dubins path, a novel coding method and the worst frog update strategy are presented. Finally, the simulation results prove that the algorithm is effective for path planning of single UAV and multiple UAVs.

关键词： path planning Dubins path shuffled frog-leaping algorithm obstacle avoidance

Prescribed-time Group Consensus Cooperative Guidance

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Prescribed-time Group Consensus Cooperative Guidance

第40届中国控制会议

作者： Wenhui Ma Yangwang fang Zhikai Wang wenxing Fu Xiaogeng Liang School of Automation Northwestern Polytechnical University Unmanned System Research Institute Northwestern Polytechnical University School of Astronautics Northwestern Polytechnical University

In this paper,a prescribed-time group consensus cooperative guidance law（PTGCCGL） is proposed based on the prescribed-time control *** from the tradition cooperation against single target,the group cooperative guidance shows its potential in intercepting multiple *** the group cooperative attack,the formation is classified into subgroups which attack their own targets ***,prescribed-time group consensus based on the time-scaling function is proved by Lyapunov stability ***,the PTGCCGL is proposed for cluster cooperation to achieve the simultaneous attack of same subgroup while keep the communication between ***,a numerical example is presented to show the effectiveness of the proposed cooperative guidance law.

关键词： Prescribed-time convergence group consensus multiple flight vehicles cooperative guidance

Distributed Array Planning Method with Layered Constraint in Multi-UAV Formation with Bearing-only Detection

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Distributed Array Planning Method with Layered Constraint in...

第43届中国控制会议

作者： Zhan Chen wenxing Fu Ruitao Zhang Bowen Ye Yangwang fang Unmanned Systems Research Institute Northwestern Polytechnical University

Multi-UAV formations for bearing-only detection are increasingly important in modern military confrontations, and the geometric array of the formation is one of the decisive factors affecting the detection accuracy of the system. This paper proposed the distributed stochastic subgradient projection algorithm(DSSPA) with layered constraint to solve this ***, the system model for cooperative positioning of UAV formation using bearing-only detection method was *** based on the constraints of safe flight altitude and fixed baseline, the UAV formation is layered. Then, the proposed DSSPA combines the idea of stochastic subgradient descent and the projection method, making it more suitable for processing the objective function including non-smooth and convex optimization parts. Simultaneously, by applying the projection operation on each feasible solution, it can ensure that the constraints of the problem are met when updating parameters. Finally, simulation experiment was set up to verify the effectiveness and superiority of the proposed distributed method in array planning of UAV formations with bearing-only detection.

关键词： UAV formation layered constraint Distributed Stochastic Algorithm Geometry Dilution of Precision