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Influence mechanism of government subsidy on the green transformation of coal company in China
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作者 xiaolei li Changsong Wu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第7期1033-1040,共8页
The optimization of government subsidies to enhance the efficiency of coal companies’green transformation constitutes a critical component in the pursuit of global sustainability.We investigate the influence mechanis... The optimization of government subsidies to enhance the efficiency of coal companies’green transformation constitutes a critical component in the pursuit of global sustainability.We investigate the influence mechanism of government subsidies on the green transformation using data from the listed coal companies in China from 2007 to 2022.According to our findings and hypothesis testing,previous government subsidies did not have a significant direct impact on coal companies’green transformation.Nevertheless,government subsidies can help coal companies transition to greener practices by promoting innovative green initiatives.Furthermore,we confirmed an indirect route:that government subsidies enable the adoption of low-carbon initiatives,which in turn could facilitate the transition of coal companies towards green practices.In addition,we discovered that the coal company’s digitization will improve this indirect route.Thus,we propose increasing the effectiveness of government subsidies in facilitating coal companies’transition to green practices by focusing on technological advancements and enhancing company digitalization. 展开更多
关键词 Government subsidy Green transformation Coal company DIGITALIZATION INNOVATION
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Event-triggered H_(∞) PI state estimation for delayed switched neural networks
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作者 Yuzhong Wang Changyun Wen xiaolei li 《Journal of Automation and Intelligence》 2024年第1期26-33,共8页
On state estimation problems of switched neural networks,most existing results with an event-triggered scheme(ETS)not only ignore the estimator information,but also just employ a fixed triggering threshold,and the est... On state estimation problems of switched neural networks,most existing results with an event-triggered scheme(ETS)not only ignore the estimator information,but also just employ a fixed triggering threshold,and the estimation error cannot be guaranteed to converge to zero.In addition,the state estimator of non-switched neural networks with integral and exponentially convergent terms cannot be used to improve the estimation performance of switched neural networks due to the difficulties caused by the nonsmoothness of the considered Lyapunov function at the switching instants.In this paper,we aim at overcoming such difficulties and filling in the gaps,by proposing a novel adaptive ETS(AETS)to design an event-based H_(∞)switched proportional-integral(PI)state estimator.A triggering-dependent exponential convergence term and an integral term are introduced into the switched PI state estimator.The relationship among the average dwell time,the AETS and the PI state estimator are established by the triggering-dependent exponential convergence term such that estimation error asymptotically converges to zero with H_(∞)performance level.It is shown that the convergence rate of the resultant error system can be adaptively adjusted according to triggering signals.Finally,the validity of the proposed theoretical results is verified through two illustrative examples. 展开更多
关键词 Switched neural networks H_(∞)performance PI state estimation Event-triggered scheme
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Consensus of second-order nonlinear multi-agent systems via sliding mode observer and controller 被引量:1
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作者 xiaolei li Xiaoyuan Luo +2 位作者 Shaobao li Jianjin li Xinping Guan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期756-765,共10页
This paper investigates the consensus problem of second-order nonlinear multi-agent systems (MASs) via the sliding mode control (SMC) approach. The velocity of each agent is assumed to be unmeasurable. A second-order ... This paper investigates the consensus problem of second-order nonlinear multi-agent systems (MASs) via the sliding mode control (SMC) approach. The velocity of each agent is assumed to be unmeasurable. A second-order sliding mode observer is designed to estimate the velocity. Then a distributed discontinuous control law based on first-order SMC is presented to solve the consensus problem. Moreover, to overcome the chatting problem, two controllers based on the boundary layer method and the super-twisting algorithm respectively are presented. It is shown that the MASs will achieve consensus under some given conditions. Some examples are provided to demonstrate the effectiveness of the proposed control laws. 展开更多
关键词 nonlinear multi-agent system sliding mode observer CONSENSUS sliding mode controller
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基于“课程思政”的基础力学教学实践思考
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作者 李欣业 韩明江 +1 位作者 李晓雷 叶楠 《西南交通大学学报(社会科学版)》 2023年第S02期244-249,共6页
发挥课堂教学在大学生思想政治教育中的主渠道作用,注重挖掘和运用各学科所蕴含的思想政治教育资源,引导大学生树立正确的世界观、人生观和价值观,是我们党在新时代关于“培养什么样的人、如何培养人以及为谁培养人”这个根本问题上对... 发挥课堂教学在大学生思想政治教育中的主渠道作用,注重挖掘和运用各学科所蕴含的思想政治教育资源,引导大学生树立正确的世界观、人生观和价值观,是我们党在新时代关于“培养什么样的人、如何培养人以及为谁培养人”这个根本问题上对高校加强和改进思想政治教育和人才培养的新定位、新要求、新任务。本文以基础力学教学为依托,阐述了可以通过哪些渠道融入课程思政元素并基于此应着力培养哪些能力以及提升哪些素质。本文的观点同样适合于除了基础力学之外的其他课程的“课程思政”;不仅适合本科生教学的“课程思政”也适合于研究生教学的“课程思政”。 展开更多
关键词 基础力学教学 课程思政 能力培养 素质提升
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Lyapunov-based fixed-time stabilization control of quantum systems
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作者 xiaolei li Changyun Wen Jiange Wang 《Journal of Automation and Intelligence》 2022年第1期48-54,共7页
In this paper,we consider the fixed-time stabilization control problem of quantum systems modeled by Schrodinger equations.Firstly,the Lyapunov-based fixed-time stability criterion is extended to finitedimensional clo... In this paper,we consider the fixed-time stabilization control problem of quantum systems modeled by Schrodinger equations.Firstly,the Lyapunov-based fixed-time stability criterion is extended to finitedimensional closed quantum systems in the form of coherence vectors.Then for a two-level quantum system with single control input,a non-smooth fractional-order control law is designed using the relative state distance.By integrating the fixed-time Lyapunov control technique and the bi-limit homogeneity theory,the quantum system is proved to be stabilized to an eigenstate of the inherent Hamiltonian in a fixed time.Comparing with existing methods in quantum system control,the proposed approach can guarantee stabilization in a fixed time without depending on the initial states. 展开更多
关键词 Quantum system Lyapunov stability Fixed-time control
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2-D distributed pose estimation of multi-agent systems using bearing measurements
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作者 Xu Fang Jitao li +1 位作者 xiaolei li lihua Xie 《Journal of Automation and Intelligence》 2023年第2期70-78,共9页
This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and position... This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and positions,while the followers can measure the relative bearings or(angular and linear)velocities in their unknown local coordinate frames.For the orientation estimation,the local relative bearings are used to obtain the relative orientations among the agents,based on which a distributed orientation estimation algorithm is proposed for each follower to estimate its orientation.For the position estimation,the local relative bearings are used to obtain the position constraints among the agents,and a distributed position estimation algorithm is proposed for each follower to estimate its position by solving its position constraints.Both the orientation and position estimation errors converge to zero asymptotically.A simulation example is given to verify the theoretical results. 展开更多
关键词 Pose estimation Distributed algorithm Bearing measurements Multi-agent system Local coordinate frame 2-D plane
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含不对称茚满结构聚酰亚胺的合成与表征 被引量:2
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作者 包春连 李晓雷 +1 位作者 陈涛 许保云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第12期7-13,20,共8页
以双酚A为原料,通过有机合成制备含不对称茚满结构的二胺单体6-(4-氨基-2-三氟甲基)苯氧基-1-[4-(4-氨基-2-三氟甲基)苯氧基]苯基-1,3,3,-三甲基茚满,并与5种二酐通过化学亚胺化法制备含茚满结构聚酰亚胺。通过红外光谱、核磁共振、溶... 以双酚A为原料,通过有机合成制备含不对称茚满结构的二胺单体6-(4-氨基-2-三氟甲基)苯氧基-1-[4-(4-氨基-2-三氟甲基)苯氧基]苯基-1,3,3,-三甲基茚满,并与5种二酐通过化学亚胺化法制备含茚满结构聚酰亚胺。通过红外光谱、核磁共振、溶解性能测试、紫外可见光谱、差示扫描量热分析、热重分析等对聚合物进行测试。结果表明,该系列聚酰亚胺室温下在低沸点溶剂如CHCl3,CH2Cl2,THF,丙酮等中也表现出非常优异的溶解性能;在450~760 nm范围内具有优异的光学性能,550 nm处透光率高达88.1%;玻璃化转变温度在228~265℃,5%热失重温度(N2氛围)在484~520℃,具有良好的热性能;拉伸强度为75.8~92.5 MPa,弹性模量为1.3~2.0 GPa,断裂伸长率为3.2%~10.8%,表现出良好的力学性能。 展开更多
关键词 聚酰亚胺 茚满结构 溶解性能 光学性能 热性能
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Detection of composition of functional component theabrownins in Pu-erh tea by degradation method 被引量:4
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作者 Simin Hu xiaolei li +5 位作者 Chuangchuang Gao Xianyu Meng Mingchao li Yuqian li Tianrui Xu Qian Hao 《Food Science and Human Wellness》 SCIE 2022年第3期643-647,共5页
Habitual tea consumption can reduce the risk of ASCVD morbidity and mortality and all-cause mortality in China,and long-term adherence to this habit can provide greater protection.Pu-erh tea is one of the representati... Habitual tea consumption can reduce the risk of ASCVD morbidity and mortality and all-cause mortality in China,and long-term adherence to this habit can provide greater protection.Pu-erh tea is one of the representatives of post-fermented teas,and the polymers in Pu-erh tea have anti-cancer and anti-hyperlipidemic activities,but their chemical composition is still unknown.In this study,the chemical composition of Pu-erh tea was investigated in detail and eight(1–8)known compounds were isolated.The polymers in Pu-erh tea were also degraded by thiol degradation,and the fragments of quercetin and(–)-epicatechin-3-O-gallate were found in the thiol degradation products of Pu-erh tea polymers by UPLC observation and separation and purification.This is the first time that this fragment was obtained in Pu-erh tea polymer. 展开更多
关键词 Pu-erh tea POLYMER THEABROWNIN Thiol degradation
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Bearing Fault Diagnosis Method of Wind Turbine Based on Improved Anti-Noise Residual Shrinkage Network
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作者 xiaolei li 《Energy Engineering》 EI 2022年第2期665-680,共16页
Aiming at the difficulty of rolling bearing fault diagnosis of wind turbine under noise environment,a new bearing fault identification method based on the Improved Anti-noise Residual Shrinkage Network(IADRSN)is propo... Aiming at the difficulty of rolling bearing fault diagnosis of wind turbine under noise environment,a new bearing fault identification method based on the Improved Anti-noise Residual Shrinkage Network(IADRSN)is proposed.Firstly,the vibration signals of wind turbine rolling bearings were preprocessed to obtain data samples divided into training and test sets.Then,a bearing fault diagnosis model based on the improved anti-noise residual shrinkage network was established.To improve the ability of fault feature extraction of the model,the convolution layer in the deep residual shrinkage network was replaced with a Dense-Net layer.To further improve the anti-noise ability of the model,the first layer of the model was set as the Drop-block layer.Finally,the labeled data samples were used for training model and the trained model was applied to the test set to output the fault diagnosis results.The results showed that the proposed method could achieve the fault diagnosis of wind turbine bearing more accurately in the high noise environment through comparison and verification. 展开更多
关键词 Bearing fault diagnosis improved residual shrinkage network noise immunity
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Break-Even Analysis on the Charging and Battery-Swapped Station of Electric Vehicles
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作者 xiaolei li Huawei Jia 《Journal of Power and Energy Engineering》 2013年第1期1-5,共5页
The construction of electric vehicle charging station plays an important role in the development of electric vehicles and the promotion of the renewable resource. In the paper, a model to analyze the economic benefit ... The construction of electric vehicle charging station plays an important role in the development of electric vehicles and the promotion of the renewable resource. In the paper, a model to analyze the economic benefit of the charging station is presented, which is based on the break-even theory. Then the threshold price is calculated based on the model according to the construction plans of charging facilities in one district. Finally, the strategy for the development of charging faculties is proposed to improve the health growth of electric automotive industry. 展开更多
关键词 Electric Vehicle CHARGING STATION Break-Even Critical CHARGING PRICE
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Convergence Rate of Solutions to a Hyperbolic Equation with p(x)-Laplacian Operator and Non-Autonomous Damping
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作者 Wenjie Gao xiaolei li Chunpeng Wang 《Communications in Mathematical Research》 CSCD 2023年第2期190-208,共19页
This paper concerns the convergence rate of solutions to a hyperbolic equation with p(x)-Laplacian operator and non-autonomous damping.We apply the Faedo-Galerkin method to establish the existence of global solutions,... This paper concerns the convergence rate of solutions to a hyperbolic equation with p(x)-Laplacian operator and non-autonomous damping.We apply the Faedo-Galerkin method to establish the existence of global solutions,and then use some ideas from the study of second order dynamical system to get the strong convergence relationship between the global solutions and the steady solution.Some differential inequality arguments and a new Lyapunov functional are proved to show the explicit convergence rate of the trajectories. 展开更多
关键词 Convergence rate energy estimate non-autonomous damping
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Management and nursing strategies for different patterns of adverse events in patients with urological cancer treated with immune checkpoint inhibitors
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作者 Xiaojuan Huang xiaolei li +1 位作者 Lulin Ma Chunxia liu 《Current Urology》 2024年第3期212-217,共6页
Background This study aimed to explore the patterns of treatment-related adverse events(AEs)associated with immune checkpoint inhibitor(ICI)monotherapy and in combination with chemotherapy or tyrosine kinase inhibitor... Background This study aimed to explore the patterns of treatment-related adverse events(AEs)associated with immune checkpoint inhibitor(ICI)monotherapy and in combination with chemotherapy or tyrosine kinase inhibitor(TKI)therapy and to summarize the corresponding management and nursing strategies.Materials and methods A total of 69 patients with malignant urological tumors who received ICI treatment between June 2019 and October 2022 were retrospectively analyzed,and AEs that occurred during treatment were observed and reported.Based on the different types of treatment,the patients were divided into ICI monotherapy,ICI plus chemotherapy,and ICI plus TKI therapy groups.Subgroup analysis was performed.The incidence,distribution,and severity of AEs in the different subgroups were evaluated.Results A total of 138 AEs occurred in 69 patients,among which grade 1 plus 2,and grade 3 plus 4 AEs accounted for 78.99%and 21.01%,respectively.The incidence of AEs per patient in the ICI-TKI therapy group was the highest(3.75 times/person),followed by the ICI-chemotherapy(2.33 times/person)and ICI monotherapy(0.82 times/person)groups.Specific AEs,such as fatigue,nausea,and myelosuppression,were much more common in the ICI-gemcitabine and cisplatin group,whereas renal injury,skin lesions,and diarrhea were most common ones in the ICI-TKI group.Conclusions Immune checkpoint inhibitors are new treatment options for advanced urological tumors and renal cell carcinoma.Distinctive AE patterns were observed among the different treatment groups.Therefore,strict and meticulous clinical management and nursing measures are required to ensure the safety of patients receiving ICI treatment. 展开更多
关键词 Immune checkpoint inhibitor IMMUNOTHERAPY Adverse events NURSING Urological tumor
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Structure,retrogradation and digestibility of waxy corn starch modified by a GtfC enzyme from Geobacillus sp.12AMOR1 被引量:3
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作者 xiaolei li Yong Wang +6 位作者 Siyu Mu Xiangqing Ji Cheng Zeng Dingkuan Yang liyuan Dai Cuicui Duan Dan li 《Food Bioscience》 SCIE 2022年第2期282-290,共9页
To lower the retrogradation and digestibility of waxy corn starch for different food applications,a novel thermostable GtfC type 4,6-α-glucanotransferase without N-and C-terminals(GsGtfC)from Geobacillus sp.12AMOR1 w... To lower the retrogradation and digestibility of waxy corn starch for different food applications,a novel thermostable GtfC type 4,6-α-glucanotransferase without N-and C-terminals(GsGtfC)from Geobacillus sp.12AMOR1 was used.Waxy corn starch of 50 g/L was incubated with GsGtfC of 40-100 U/g substrate at 65℃and pH 5.5 for 1 h.Its molecular weight,iodine affinity,XRD crystallinity,and FTIR ratio of heights of bands at 1047 and 1022 cm^(-1) decreased,but ratio of DP<6 to DP≥25 branches and degree of branching increased.GsGtfC cleavedα-1,4-glycosidic bonds and inducedα-1,6-branching points to produce reuteran-likes polymers,which is different from Exiguobacterium sibiricum GtfC enzyme cleavingα-1,4-glycosidic bonds and synthesizing consecutiveα-1,6-glycosidic bonds to produce isomalto/malto-oligosaccharides.GsGtfC modified waxy corn starch had significantly lower DSC retrogradation enthalpies during the storage at 4℃for 3-14 days and significantly lower released glucose during the incubation with mammalian mucosalα-glucosidase at 37℃for 10-360 min.GsGtfC at 100 U/g substrate increased slowly digestible portion from 11.07%to 24.11%. 展开更多
关键词 Waxy corn starch STRUCTURE RETROGRADATION DIGESTIBILITY GtfC 4 6-α-glucanotransferase
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Optimal model establishment of whole-process management data for CAR-T therapy in China—how should this be done? 被引量:3
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作者 xiaolei li Hanren Dai +4 位作者 Xian li Ping li Wenbin Qian Aibin liang Weidong Han 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2022年第1期122-124,共3页
Chimeric antigen receptor(CAR)T-cell therapy utilizes patients’own T lymphocytes that are engineered to attack cancer cells[1,2,3].With the US Food and Drug Administration(FDA)approval of four CD19-and one BCMA-targe... Chimeric antigen receptor(CAR)T-cell therapy utilizes patients’own T lymphocytes that are engineered to attack cancer cells[1,2,3].With the US Food and Drug Administration(FDA)approval of four CD19-and one BCMA-targeted CAR therapy for B cell malignancies[4,5],CAR T-cell therapy has finally reached the status of a medicinal product. 展开更多
关键词 CAR LYMPHOCYTES utilize
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DNA methylation-mediated repression of miR-181a/135a/302c expression promotes the microsatellite-unstable colorectal cancer development and 5-FU resistance via targeting PLAG1 被引量:9
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作者 Lu Shi Xiang li +5 位作者 Zhiqiang Wu xiaolei li Jing Nie Mingzhou Guo Qian Mei Weidong Han 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2018年第4期205-214,共10页
Micro sate Hite instability(MSI) defines a subtype of colorectal cancer(CRC) with typical clinicopathologic characteristics. CRCs with MSI(MSI CRCs) frequently acquire accelerated carcinogenesis and 5-FU resista... Micro sate Hite instability(MSI) defines a subtype of colorectal cancer(CRC) with typical clinicopathologic characteristics. CRCs with MSI(MSI CRCs) frequently acquire accelerated carcinogenesis and 5-FU resistance, and the exact underlying mechanism remains incompletely understood. Our previous study has identified the microRNA(miRNA) expression profile in MSI CRCs. In this study, three miRNAs(miR-181 a, miR-135 a and miR-302 c) were validated by qRT-PCR to be dramatically decreased in 67 CRC samples. Proliferation and apoptosis assays demonstrated that miR-181 a/135 a/302 c function as tumor suppressors via repressing PLAG1/IGF2 signaling. Moreover, we presented compelling evidence that restoration of miR-181 a/135 a/302 c expression promoted sensitivity of MSI CRC cells to 5-FU treatment. miR-181 a/135 a/302 c exerted their effect on chemoresistance through attenuating PLAG1 expression. Notably, the hypermethylation status of MSI CRC accounts for the decrements of miR-181 a/135 a/302 c. Our results contribute to a better understanding of the mechanism of chemo?resistance in MSI CRCs, and provide a clue for digging the bio markers and therapeutic targets for CRC patients. 展开更多
关键词 Colorectal cancer Microsatellite instability microRNA PLAG1 Chemoresistance 5-FU
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Type I vaccine-derived polioviruses in China from 1995 to 2019 被引量:2
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作者 Yong Zhang Shuangli Zhu +5 位作者 Dongmei Yan Dongyan Wang xiaolei li Hui Zhu Hongqiu An Wenbo Xu 《Biosafety and Health》 2019年第3期155-158,共4页
A nation-wide case surveillance was conducted in China since 1995 for the objective of identifying acute flaccid paralysis(AFP)in children so that potential wild polioviruses and vaccine-derived poliovirus(VDPV)could ... A nation-wide case surveillance was conducted in China since 1995 for the objective of identifying acute flaccid paralysis(AFP)in children so that potential wild polioviruses and vaccine-derived poliovirus(VDPV)could be identified on time.Two outbreaks associated with type I circulating VDPVs,eight native independent type I ambiguous VDPVs(aVDPV),and one imported aVDPV were identified during the AFP case surveillance in China from 1995 to 2019.The VP1 coding region of the Chinese type I VDPVs differed from the polio vaccine strain by 1.00%–3.75%(9–34 substitutions in 906 nucleotides).Most of the Chinese type I VDPV strains shared 4 amino acid substitutions in the neutralizing antigenic(NAg)sites:3 located at the BC loop,which formed the NAg site 1,and another at NAg site 3a.All of the Chinese type I VDPVs identified during the AFP case surveillance were young VDPVs,which indicated a limited viral replication resulted from the administration of the initiating oral polio vaccine(OPV)dose.VDPVs can emerge and spread in isolated communities with immunity gaps and the circulation ceases following a mass immunization with OPV.As such,high-quality surveillance permitted very early detection and response and it played a key role in stalling the widespread circulation of the emergent cVDPV strains in China. 展开更多
关键词 Type I Vaccine-derived poliovirus Phylogenetic analysis Neutralizing antigenic sites
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Hydrothermal conversion of lignin and black liquor for phenolics with the aids of alkali and hydrogen donor 被引量:4
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作者 Cuina Peng Guangyi Zhang +1 位作者 Jiangze Han xiaolei li 《Carbon Resources Conversion》 2019年第2期141-150,共10页
The potentials of phenolic productions from lignin and black liquor(BL)via hydrothermal technology with the aids of alkalis and hydrogen donors were investigated,by conducting batch experiments in micro-tube reactors ... The potentials of phenolic productions from lignin and black liquor(BL)via hydrothermal technology with the aids of alkalis and hydrogen donors were investigated,by conducting batch experiments in micro-tube reactors with 300℃ sub-critical water as the solvent.The results showed that all the employed alkalis improved lignin degradation and thus phenolics production,and the strong alkalis additionally manifested deoxygenation to produce more phenolics free of methoxyl group(s).Relatively,hydrogen donors more visibly facilitated phenolics formation.Combination of strong alkali and hydrogen donors exhibited synergistically positive effects on producing phenolics(their total yield reaching 22 wt%)with high selectivities to phenolics,among which the yields of catechol and cresols respectively peaked 16 and 3.5 wt%.BL could be hydrothermally converted into phenolics at high yields(approaching 10 wt%with the yields of catechol and cresols of about 4 and 2 wt%,respectively)with the aids of its inherent alkali and hydrogen donors,justifying its cascade utilization. 展开更多
关键词 Hydrothermal technology Phenolics LIGNIN ALKALI Hydrogen donor
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Multiple measurements of quasars acting as standard probes: Model independent calibration and exploring the dark energy equation of states 被引量:1
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作者 XiaoGang Zheng Shuo Cao +3 位作者 Marek Biesiada xiaolei li TongHua liu YuTing liu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2021年第5期97-109,共13页
Recently, two classes of quasar samples were identified, which are promising as new cosmological probes extending to higher redshifts. The first sample uses the nonlinear relation between the ultraviolet and X-ray lum... Recently, two classes of quasar samples were identified, which are promising as new cosmological probes extending to higher redshifts. The first sample uses the nonlinear relation between the ultraviolet and X-ray luminosities of quasars to derive luminosity distances, whereas the linear sizes of compact radio quasars in the second sample can serve as standardized rulers, providing angular-diameter distances. In this study, under the assumption of a flat universe, we refreshed the calibration of multiple measurements of high-redshift quasars(in the framework of a cosmological-model-independent method with the newest Hubble parameters data). Furthermore, we placed constraints on four models that characterize the cosmic equation of state(w). The obtained results show that:(1) the two quasar samples could provide promising complementary probes at much higher redshifts,whereas compact radio quasars perform better than ultraviolet and X-ray quasars at the current observational level;(2) strong degeneracy between the cosmic equation of state(w) and Hubble constant(H0) is revealed, which highlights the importance of independent determination of H0 from time-delay measurements of strongly lensed quasars;(3) together with other standard ruler probes, such as baryon acoustic oscillation distance measurements, the combined QSO+BAO measurements are consistent with the standard ΛCDM model at a constant equation of state w =-1;(4) ranking the cosmological models, the polynomial parametrization gives a rather good fit among the four cosmic-equation-of-state models, whereas the Jassal-Bagla-Padmanabhan(JBP) parametrization is substantially penalized by the Akaike Information Criterion and Bayesian Information Criterion. 展开更多
关键词 dark energy experiments dark energy theory QUASARS
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Epidemiological survey and genetic characterization of type 3 vaccine-derived poliovirus isolated from a patient with four doses of inactivated polio vaccine in Henan Province,China
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作者 Mingyu Zhang Jianhui Yang +16 位作者 Yiran Bai Hui Zhu Changshuang Wang Lu Zhang Jin Xu Mingxia Lu Xiaoxiao Zhang Zhanpei Xiao Yating Ma Yan Wang xiaolei li Dongyan Wang Shuangli Zhu Dongmei Yan Wenbo Xu Yong Zhang Yanyang Zhang 《Infectious Diseases of Poverty》 SCIE 2022年第6期99-100,共2页
Background:Vaccine-derived poliovirus(VDPV)is a potential threat to polio eradication because they can reintroduce into the general population and cause paralytic polio outbreaks,a phenomenon that has recently emerged... Background:Vaccine-derived poliovirus(VDPV)is a potential threat to polio eradication because they can reintroduce into the general population and cause paralytic polio outbreaks,a phenomenon that has recently emerged as a prominent public health concern at the end of global polio eradication.This study aimed to describe the epidemiology and genetic characteristics of the frst VDPV identifed from a patient with acute faccid paralysis(AFP),with four doses of inactivated polio vaccine immunization in Henan Province,China in 2017.Methods:The patient was diagnosed with type 3 VDPV.Subsequently,a series of epidemiological approaches was implemented,including a retrospective search of AFP cases,rate of vaccination assessment,study of contacts,and supplementary immunization activities.Fecal samples were collected,viral isolation was performed,and the viral isolates were characterized using full-length genomic sequencing and bioinformatic analysis.Results:Phylogenetic analysis showed that the viral isolates from the patient were diferent from other reported genetic clusters of type 3 VDPV worldwide.They were identifed as a Sabin 3/Sabin 1 recombinant VDPV with a crossover site in the P2 region.Nucleotide substitutions,including U→C(472)and C→U(2493),have been identifed,both of which are frequently observed as reversion mutations in neurovirulent type 3 poliovirus.A unique aspect of this case is that the patient had been vaccinated with four doses of inactive polio vaccine,and the serum neutralizing antibody for Sabin types 1 and 3 were 1∶16 and 1∶512,respectively.Thus,the patient was speculated to have been infected with type 3 VDPV,and the virus continued to replicate and be excreted for at least 41 d.Conclusions:The existence of this kind of virus in human population is a serious risk and poses a severe challenge in maintaining a polio-free status in China.To the best of our knowledge,this is the frst report of VDPV identifed in the Henan province of China.Our results highlight the importance of maintaining a high-level vaccination rate and highly sensitive AFP case surveillance system in intercepting VDPV transmission. 展开更多
关键词 Epidemiological Survey Genetic characterization Type 3 vaccine-derived poliovirus Recombination HENAN China
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Boosting the lithium-ion storage performance of perovskite Sr_(x)VO_(3-δ) via Sr cation and O anion deficient engineering
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作者 xiaolei li Zifeng lin +9 位作者 Na Jin Xiaojiao Yang Lei Sun Yuan Wang Lei Xie Xiping Chen li Lei Patrick Rozier Patrice Simon Ying liu 《Science Bulletin》 SCIE EI CAS CSCD 2022年第22期2305-2315,共11页
Perovskite SrVO_(3) has been investigated as a promising lithium storage anode where the V cation plays the role of the redox center,combining excellent cycle stability and safe operating potential versus Li metal pla... Perovskite SrVO_(3) has been investigated as a promising lithium storage anode where the V cation plays the role of the redox center,combining excellent cycle stability and safe operating potential versus Li metal plating,with limited capacity.Here,we demonstrate the possibility to boost the lithium storage properties,by reducing the non-redox active Sr cation content and fine-tuning the O anion vacancies while maintaining a non-stoichiometric Sr_(x)VO_(3-δ) perovskite structure.Theoretical investigations suggest that Sr vacancy can work as favorable Li^(+) storage sites and preferential transport channels for guest Li^(+) ions,contributing to the increased specific capacity and rate performance.In contrast,inducing O anion vacancy in Sr_(x)VO_(3-δ) can improve rate performance while compromising the specific capacity.Our experimental results confirm the enhancement of specific capacities by fine adjusting the Sr and O vacancies,with a maximum capacity of 444 mAh g^(-1) achieved with Sr_(0.63)VO_(3-δ),which is a 37%increase versus stoichiometric SrVO_(3).Although rich defects have been induced,Sr_(x)VO_(3-δ) electrodes maintain a stable perovskite structure during cycling versus a LiFePO_(4) cathode,and the full-cell could achieve more than 6000 discharge/charge cycles with 80%capacity retention.This result highlights the possibility to use the cation defective-based engineering approach to design high-capacity perovskite oxide anode materials. 展开更多
关键词 PEROVSKITE Sr vacancy Non-stoichiometric Sr_(x)VO_(3-δ) O vacancy Defective-based engineering
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