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Detection of reassortant avian influenza A (H11N9) virus in environmental samples from live poultry markets in China

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Infectious Diseases of Poverty 2016年第1期5卷 499-504页

作者： Ye Zhang Shu-Mei Zou Xiao-Dan li li-bo dong Hong bo Rong-Bao Gao Da-Yan Wang Yue-Long Shu National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Key Laboratory for Medical Virology National Health and Family Planning CommissionBeijing 102206China

Background:Avian influenza viruses have caused human infection and posed the pandemic potential.live poultry markets are considered as a source of human infection with avian influenza viruses.Avian influenza routine surveillance of live poultry markets is taken annually in China.We isolated the 2 H11N9 influenza virus from the surveillance program.To better understand the risk caused by these new viruses,we characterize the genetic and pathogenicity of the two viruses.Methods:Viral isolation was conducted with specific pathogen-free(SPF)embryonated chicken eggs.Whole genome was sequenced,and phylogenetic analysis was conducted.Results:Two H11N9 viruses were identified,with all 8 segments belonging to the Eurasian lineage.The HA,NA,M,NS and PA genes were similar to virus isolates from ducks,and the NP,PB2 and PB1 gene segments were most similar to those viruses from wild birds,indicating that the H11N9 viruses might represent reassortant viruses from poultry and wild birds.The HA receptor binding preference was avian-like,and the cleavage site sequence of HA showed low pathogenic.The NA gene showed 94.6%identity with the novel H7N9 virus that emerged in 2013.There was no drug resistance mutation in the M2 protein.The Asn30Asp and Thr215Ala substitutions in the M1 protein implied a potentially increased pathogenicity in mice.both viruses were low-pathogenic strains,as assessed by the standards of intravenous pathogenicity index(IVPI)tests.Conclusion:Two reassortant H11N9 avian influenza viruses were detected.These viruses showed low pathogenicity to chickens in the IVPI test.Public health concern caused by the reassortant H11N9 viruses should be emphasized during the future surveillance.

关键词： Avian influenza H11N9 Genetic characterization Reassortant

Animal models of eosinophilic esophagitis,review and perspectives

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Animal Models and Experimental Medicine 2024年第2期7卷 127-135页

作者： dong li Yujia Wei Jing Wang bo Wang Department of Dermatology Huazhong University of Science and Technology Tongji Medical College Tongji HospitalWuhanChina Health Management Center Huazhong University of Science and Technology Tongji Medical College Tongji HospitalWuhanChina Department of Gastroenterology Huazhong University of Science and Technology Tongji Medical College Tongji HospitalWuhanChina

Eosinophilic oesophagitis(EoE)is an allergen/immune-mediated chronic esophageal disease characterized by esophageal mucosal eosinophilic infiltration and esophageal dysfunction.Although the disease was originally attributed to a delayed allergic reaction to allergens and a Th2-type immune response,the exact pathogenesis is complex,and the efficacy of existing treatments is unsatisfactory.Therefore,the study of the pathophysiological process of EOE has received increasing attention.Animal models have been used extensively to study the molecular mechanism of EOE pathogenesis and also provide a preclinical platform for human clinical intervention studies of novel therapeutic agents.To maximize the use of existing animal models of EOE,it is important to understand the advantages or limitations of each modeling approach.This paper systematically describes the selection of experimental animals,types of allergens,and methods of sensitization and excitation during the preparation of animal models of EoE.It also discusses the utility and shortcomings of each model with the aim of providing the latest perspectives on EoE models and leading to better choices of animal models.

关键词： anaphylaxis disease models animal eosinophilic esophagitis methods

铜冶炼企业中原料库智能天车的功能需求及关键技术探析

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世界有色金属 2024年第8期 33-35页

作者：马佳陈忠良李东波钱强云南铜业股份有限公司西南铜业分公司云南昆明650102

铜冶炼行业中原料的搬运大多依靠人工驾驶天车进行,员工劳动强度大,天车运行效率不高,信息及现场管理原始粗放,急需借助智能化手段优化原有作业模式,以减轻员工劳动强度,提高生产效率,改善工作环境,实现无人化管理。针对以上问题及优化... 详细信息

铜冶炼行业中原料的搬运大多依靠人工驾驶天车进行,员工劳动强度大,天车运行效率不高,信息及现场管理原始粗放,急需借助智能化手段优化原有作业模式,以减轻员工劳动强度,提高生产效率,改善工作环境,实现无人化管理。针对以上问题及优化目标,对多品种物料原料库智能天车的软硬件功能需求以及精准定位技术、吊具防摇摆等关键技术进行探析,为后续深入设计和实施提供技术支撑。

关键词：智能天车 3D激光扫描智能调度仓储管理精准定位吊具防摇

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某扭杆驱动的折叠舵设计

机械工程与自动化 2024年第2期 93-94,97页

作者：杨志远李东博鲁霄光张雷北京航天飞腾装备有限技术责任公司北京100080

利用扭杆作为驱动能源进行折叠舵展开设计,实现大尺寸舵面的横向折叠结构设计。通过该设计方案可减小外包络尺寸,从而有效降低了储、运、发包络尺寸要求,提高了产品的平台适应性。考虑润滑摩擦边界下,展开到位时间为135 ms,到位速度为24... 详细信息

利用扭杆作为驱动能源进行折叠舵展开设计,实现大尺寸舵面的横向折叠结构设计。通过该设计方案可减小外包络尺寸,从而有效降低了储、运、发包络尺寸要求,提高了产品的平台适应性。考虑润滑摩擦边界下,展开到位时间为135 ms,到位速度为24.39 rad/s。通过动力学仿真验证,结果表明该产品设计满足性能要求,可为其他类似产品的设计提供参考。

关键词：折叠舵扭杆仿真验证驱动

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research(International) 2024年第4期31卷 894-908页

作者： Yan-li Xin Zhi-ying Gao bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product quality.Macroscopic instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction coefficient.However,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is applied.Subsequently,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling mill.On one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is determined.Furthermore,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Numerical Investigations on the Resonance Errors of Multiscale Discontinuous Galerkin Methods for One-Dimensional Stationary Schrödinger Equation

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Communications on Applied Mathematics and Computation 2024年第1期6卷 311-324页

作者： bo dong Wei Wang Department of Mathematics University of Massachusetts DartmouthNorth DartmouthMA02747USA Department of Mathematics and Statistics Florida International UniversityMiamiFL33199USA

In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(dong et al.in J Sci Comput 66:321–345,2016;dong and Wang in J Comput Appl Math 380:1–11,2020)for a one-dimensional stationary Schrödinger equation.Previous work showed that penalty parameters were required to be positive in error analysis,but the methods with zero penalty parameters worked fine in numerical simulations on coarse meshes.In this work,by performing extensive numerical experiments,we discover that zero penalty parameters lead to resonance errors in the multiscale DG methods,and taking positive penalty parameters can effectively reduce resonance errors and make the matrix in the global linear system have better condition numbers.

关键词： Discontinuous Galerkin(DG)method Multiscale method Resonance errors One-dimensional Schrödinger equation

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： dong Wen-bo ZHOU li DING Shi-feng WANG Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

R2R3-type Lo MYB21 affects jasmonate-regulated development and dehiscence of anthers in lily(lilium oriental hybrids)

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Horticultural Plant Journal 2024年第1期10卷 239-251页

作者： Zheng Tong Tingting dong Qiuhua li Rui Wang Junna He bo Hong Institute of Tropical Bioscience and Biotechnology Chinese Academy of Tropical Agricultural Sciences&Hainan Institute for Tropical Agricultural ResourcesHaikouHainan 571101China Beijing Key Laboratory of Development and Quality Control of Ornamental Crops Department of Ornamental HorticultureChina Agricultural UniversityBeijing 100193China Beijing Garden Expo Management Center Beijing 100072China

lilies are widely cultivated for cut flowers,but their large anthers carry a considerable amount of colored pollen that is dispersed easily.Studying the molecular mechanism of anther development and dehiscence could help solve this problem.LoMYB21,encoding a putative R2R3v-myb avian myeloblastosis viral oncogene homolog(MYB)transcription factor,was identified from oriental lilies(lilium‘Siberia’).Real-time quantitative PCR analysis showed that LoMYB21 was mainly expressed in the anther,filament and stigma and had high expression during the late stages of lily anther development.LoMYB21 had transactivation activity and was located in the nucleus through yeast one-hybrid assays and transient expression in Nicotiana benthamiana.Suppression of LoMYB21 by virus-induced gene silencing(VIGS)in lilium‘Siberia’led to anther indehiscence and reduced the expression of genes related to Jasmonate acid(JA)biosynthesis and signal transduction.Induction of LoMYB21 in DEX::LoMYB21 transgenic Arabidopsis caused procumbent inflorescences that became infertile,accompanied by higher expression of JA biosynthetic and signaling genes.These results demonstrated that JA content and signaling were abnormal in silenced lily and transgenic LoMYB21 Arabidopsis,which affected anther development.Our study indicated that LoMYB21 could regulate lily anther dehiscence through JA biosynthesis and signaling during the late stages of anther development.

关键词： lilium LoMYB21 Anther dehiscence Jasmonate acid

Mechanism of Diabatic Heating on Precipitation and the Track of a Tibetan Plateau Vortex over the Eastern Slope of the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第1期41卷 155-172页

作者： Yuanchang dong Guoping li Xiaolin XIE Long YANG Peiwen ZHANG bo ZENG Institute of Plateau Meteorology China Meteorological Administration(CMA)/Heavy Rain and Drought-Flood Disaster in Plateau and Basin Key Laboratory of Sichuan ProvinceChengdu 610072China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Meteorological Observation Data Center of Sichuan Province Chengdu 610072China Sichuan Branch of Meteorologist Training Institute CMAChengdu 610072China

Existing studies contend that latent heating(LH)will replace sensible heating(SH)to become the dominant factor affecting the development of the Tibetan Plateau vortex(TPV)after it moves off the Tibetan Plateau(TP).However,in the process of the TPV moving off the TP requires that the airmass traverse the eastern slope of the Tibetan Plateau(ESTP)where the topography and diabatic heating(DH)conditions rapidly change.How LH gradually replaces SH to become the dominant factor in the development of the TPV over the ESTP is still not very clear.In this paper,an analysis of a typical case of a TPV with a long life history over the ESTP is performed by using multi-sourced meteorological data and model simulations.The results show that SH from the TP surface can change the TPV-associated precipitation distribution by temperature advection after the TPV moves off the TP.The LH can then directly promote the development of the TPV and has a certain guiding effect on the track of the TPV.The SH can control the active area of LH by changing the falling area of the TPV-associated precipitation,so it still plays a key role in the development and tracking of the TPV even though it has moved out of the main body of the TP.

关键词： eastern slope of the Tibetan Plateau diabatic heating Tibetan Plateau vortex precipitation distribution track