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Genetic Characteristics of 2009 Pandemic H1N1 Influenza A Viruses Isolated from China's Mainland

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Virologica Sinica 2011年第6期26卷 418-427页

作者： Jiu-ru Zhao Yong-dong li li-min Pan Na Zhu Hong-xia Ni Guo-zhang Xu Yong-zhong Jiang Xi-xiang Huo Jun-qiang Xu Han Xia Na Han Shuang Tang Zhong Zhang Zheng Kou Simon Rayner tian-xian li State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China Center for Disease Control and Prevention Ningbo 315000 Zhejiang China Center for Disease Control and Prevention Wuhan 430071 China

A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic （H1N1） viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology （96%-99%） with known epidemic strains （A/Califomia/04/2009（H1N1）. Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 （221-228） of the HA receptor binding site in the 39 HA sequences： A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.

关键词： H1N1 Phylogenetic analysis Key sites Mutations

Environmental concentration of ammonia nitrogen induced marked changes in proteome of clam Ruditapes philippinarum in dose-and time-dependent manner

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Journal of Oceanology and limnology 2024年第5期42卷 1634-1650页

作者： Ming CONG Zhaoshun li Wenwen tian Yuanmei li Jiasen LÜ School of Ocean Yantai UniversityYantai 264005China School of life Sciences Yantai UniversityYantai 264005China

Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes ***,knowledge is lacking regarding the related proteins involved in the toxicological responses,which is vital to elucidate the underlying mechanism of ammonia *** this study,clams *** were exposed to ammonia nitrogen for 21 d at two environmentally relevant *** tandem mass tags approach(TMT)was applied to assay the differentially expressed proteins(DEPs)in clam gill tissues on the 3 rd and 21 st ***,a total of 7263 proteins were *** analyses revealed that clam protein profiles changed in dose-and time dependent manner after ammonia nitrogen *** inferred that the clams may face heavy challenges after ammonia exposure,such as unbalanced gender ratio,lysosomal disease,energy lack,neurological disorders,altered glutamine metabolism,increased lipid synthesis,and impaired *** profiles of enzyme activities of glutaminase and glutamine synthase provided direct evidence to verify the related inference from proteome *** of the inferred toxic effects merit further *** study identified important proteins related to ammonia nitrogen toxicity in the clam and indicated the severe stress of marine ammonia pollution on the healthy development of mollusc aquaculture.

关键词： ammonia nitrogen Ruditapes philippinarum proteomic analysis toxicity

Non-Targeted Metabolomics Reveals the Metabolic Alterations in Response to Artificial Selective Breeding in the Fast-Growing Strains of Pacific Oyster

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Journal of Ocean University of China 2024年第2期23卷 518-528页

作者： HU Boyang tian Yuan liU Shikai li Qi Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Laoshan LaboratoryQingdao 266237China

Pacific oyster(Crassostrea gigas)is one of the most important mollusks cultured all around the *** breeding programs of Pacific oysters in China is initiated since 2006 and developed the genetically improved strain with fast-growing ***,little is known about the metabolic signatures of the fast-growing *** the present study,the non-targeted metabolomics was performed to analyze the metabolic signatures of adductor muscle tissue in one-year old Pacific oysters from fast-growing strain and the wild population.A total of 7767 and 10174 valid peaks were extracted and quantified in ESI^(+)and ESI^(−)modes,resulting in 399 and 381 annotated metabolites,*** and OPLS-DA revealed that considerable separation among samples from fastgrowing strain and wild population,suggesting the differences in metabolic ***,81 significantly different metabolites(SDMs)were identified in the comparisons between fast-growing strain and wild population,based on the strict *** was found that there were highly correlation and conserved coordination among these *** enrichment analysis indicated that the SDMs were tightly related to pantothenate and CoA biosynthesis,steroid hormone biosynthesis,riboflavin metabolism,and arginine and proline *** them,the CoA biosynthesis and metabolism,affected by pantetheine and pantothenic acid,might be important for the growth of Pacific oysters under artificial selective *** study provides the comprehensive views of metabolic signatures in response to artificially selective breeding,and is helpful to better understand the molecular mechanism of fastgrowing traits in Pacific oysters.

关键词： metabolic signature Pacific oyster artificial selection fast-growing trait

Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang li xian-Ming Xiao Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng li School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing100083 China

The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well *** the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were *** results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM *** pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,*** methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,*** with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption *** GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content oflittle shale gas *** the geological and geochemical conditions of shale gas formation a

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor

A novel interpretable multilevel wavelet decomposition deep network for actual heartbeat classification

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Science China(Technological Sciences) 2024年第6期67卷 1842-1854页

作者： JIN YanRui li ZhiYuan tian YuanYuan WEI XiaoYang liU Chengliang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China

Arrhythmias may lead to sudden cardiac death if not detected and treated in time.A supraventricular premature beat(SPB)and premature ventricular contraction(PVC)are important categories of arrhythmia ***,deep learning methods have been applied to the PVC/SPB heartbeats ***,most researchers have focused on time-domain information of the electrocardiogram and there has been a lack of exploration of the interpretability of the *** this study,we design an interpretable and accurate PVC/SPB recognition algorithm,called the interpretable multilevel wavelet decomposition deep network(IMWDDN).Wavelet decomposition is introduced into the deep network and the squeeze and excitation(SE)-Residual block is designed for extracting time-domain and frequency-domain ***,inspired by the idea of residual learning,we construct a novel loss function for the constant updating of the multilevel wavelet decomposition ***,the IMWDDN is evaluated on the Third China Physiological Signal Challenge Dataset and the MIT-BIH Arrhythmia *** comparison results show IMWDDN has better detection performance with 98.51%accuracy and a 93.75%F1-macro on average,and its areas of concern are similar to those of an expert diagnosis to a certain ***,the IMWDDN has good application value in the clinical screening of PVC/SPB heartbeats.

关键词： actual heartbeat classification electrocardiogram interpretable deep network multilevel discrete wavelet decomposition layer SE-Residual block

Mechanical properties and microstructure of Mg-treated and Catreated industrial H13 steel after quenching and tempering

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Journal of Iron and Steel Research International 2024年第8期31卷 1987-2001页

作者： Jun-ying Yue Dong Hou De-yong Wang tian-peng Qu xiang-long li Jun tian School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The effect of magnesium treatment and calcium treatment on the microstructure and mechanical properties of industrial H13 steel after quenching and tempering was *** impact toughness and tensile tests were mainly carried out,and the microstructure was observed by scanning electron microscopy,electron backscattered diffraction,and X-ray *** results show that magnesium treatment is still feasible in industrial *** is mainly manifested in the refinement of lath martensite and *** with calcium treatment,the prior austenite grains and carbides size of industrial H13 steel treated with magnesium decreased by 3.17μm after *** quenching and tempering,the carbides(especially V-rich carbides)in Mg treatment obviously spheroidized and distributed uniformly and increased in quantity *** lath martensite size is reduced from 2.45 to 2.31μ*** suggests that magnesium treatment was able to yield smaller grains and more evenly distributed ***,the impact toughness,yield strength,and ultimate tensile strength of industrial H13 steel with magnesium treatment increased by 28%,65.5 MPa and 123.7 MPa,*** increment of strength mainly comes from dislocation strengthening,grain refinement strengthening,and precipitation strengthening,among which precipitation strengthening accounts for the largest proportion.

关键词： Industrial H13 steel Mg treatment Heat treatment Carbide-Mechanical property

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu Zhang Yi Zhang Wen-hao tian Yan li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution

Aerodynamic Analysis and Optimization of Pantograph Streamline Fairing for High-Speed Trains

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1075-1091页

作者： xiang Kan Yan li tian li Jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China Technical Center Southwest Jiaotong University Chengdu Design Institute Co.Ltd.Chengdu610031China

A pantograph serves as a vital device for the collection of electricity in ***,its aerodynamic resistance can limit the train’s running *** installing fairings around the pantograph is known to effectively reduce the resistance,in this study,different fairing lengths are considered and the related aerodynamic performances of pantograph are *** particular,this is accomplished through numerical simulations based on the k-ωShear Stress Transport(SST)two-equation turbulence *** results indicate that the fairing diminishes the direct impact of high-speed airflow on the pantograph,thereby reducing its aerodynamic ***,it also induces interferences in the flow field around the train,leading to variations in the aerodynamic resistance and lift of train *** is shown that a maximum reduction of 56.52%in pantograph aerodynamic resistance and a peak decrease of 3.38%in total train aerodynamic resistance can be achieved.

关键词： Pantograph fairing train aerodynamic numerical simulation

Resource-saving scheduling scheme for centralized target tracking in multiple radar system under automatic blanket jamming

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Chinese Journal of Aeronautics 2024年第5期37卷 349-362页

作者： Zhengjie li Yujie WEI Junwei XIE Haowei ZHANG Yu tian Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Xi’an Flying College Xi’an 710300China Air and Missile Defense Institute Air Force Research InstituteBeijing 100085China School of Economics and Management Beihang UniversityBeijing 100191China

This paper investigates the problem of Joint Radar Node Selection and Power Allocation(JRNSPA)in the Multiple Radar System(MRS)in the blanket jamming *** radar node independently tracks moving target and subsequently transmits the raw observation data to the fusion center,which formulates a centralized tracking network *** order to establish a practical blanket jamming environment,we suppose that each target carries the self-defense jammer which automatically implements blanket jamming to the radar nodes that exceed the preset interception ***,the Predicted Conditional Cramer-Rao Lower Bound(PC-CRLB)is derived and utilized as the tracking accuracy *** at ensuring both the tracking performance and the Low Probability of Intercept(LPI)performance,the resource-saving scheduling model is formulated to minimize the transmit power consumption while meeting the requirements of tracking ***,the Modified Zoutendijk Method Of Feasible Directions(MZMFD)-based two-stage solution technique is adopted to solve the formulated non-convex optimization *** results show the effectiveness of the proposed JRNSPA scheme.

关键词： Multiple Radar System(MRS) Centralized target tracking Resource scheduling Blanket jamming Low Probability of Intercept(LPI)