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Control of highly pathogenic avian influenza through vaccination

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Journal of Integrative Agriculture 2024年第5期23卷 1447-1453页

作者： Xianying Zeng Jianzhong shi Hualan Chen State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin150069China

The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to *** this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and *** addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.

关键词： avian influenza control highly pathogenic vaccination

Occurrence of microplastics in natural and farmland soil in the Qilian Mountains of the Northern Tibetan Plateau

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Journal of Mountain Science 2024年第7期21卷 2159-2172页

作者： kang Qiangqiang ZHANG Yulan kang shichang ZHANG Shengyin LUO Xi LI Longrui WANG Zhaoqing ZHANG Shuncun Key Laboratory of Petroleum Resources Exploration and Evaluation Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China

Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern ***,the status of MPs in natural and farmland soils in remote areas remains poorly *** this study,we investigated the characteristics of MPs in natural and farmland soils along two transects in the Qilian Mountains of the northern Tibetan *** average abundance of MPs in natural and farmland soils was 29,778 and 56,123 items kg^(-1),respectively,with a detection size range of 10-1000μ*** in the size range of 10-100μm accounted for 84.1%of particles *** the 21 polymers detected,polyethylene dominated in both farmland and natural *** shape of MPs was dominated by fragments(95.8%),followed by fibers(3.8%)and beads(0.4%).The abundance of MPs was positively correlated with increasing altitude in natural *** was no significant correlation between the abundance of MPs and soil physicochemical properties due to the narrow range of values of soil physicochemical *** the growing concern regarding MPs pollution,research on the status of MPs in high altitude and remote areas is critical to understanding their global cycle.

关键词： Microplastics pollution Soil Remote areas Tibetan Plateau

Induced pluripotent stem cells(iPSCs):molecular mechanisms of induction and applications

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2065-2090页

作者： Jonas Cerneckis Hongxia Cai Yanhong shi Department of Neurodegenerative Diseases Beckman Research Institute of City of HopeDuarteCA 91010USA Irell&Manella Graduate School of Biological Sciences Beckman Research Institute of City of HopeDuarteCA 91010USA

The induced pluripotent stem cell(iPSC)technology has transformed in vitro research and holds great promise to advance regenerative *** have the capacity for an almost unlimited expansion,are amenable to genetic engineering,and can be differentiated into most somatic cell *** have been widely applied to model human development and diseases,perform drug screening,and develop cell *** this review,we outline key developments in the iPSC field and highlight the immense versatility of the iPSC technology for in vitro modeling and therapeutic *** begin by discussing the pivotal discoveries that revealed the potential of a somatic cell nucleus for reprogramming and led to successful generation of *** consider the molecular mechanisms and dynamics of somatic cell reprogramming as well as the numerous methods available to induce ***,we discuss various iPSC-based cellular models,from mono-cultures of a single cell type to complex three-dimensional organoids,and how these models can be applied to elucidate the mechanisms of human development and *** use examples of neurological disorders,coronavirus disease 2019(COVID-19),and cancer to highlight the diversity of disease-specific phenotypes that can be modeled using iPSC-derived *** also consider how iPSC-derived cellular models can be used in high-throughput drug screening and drug toxicity ***,we discuss the process of developing autologous and allogeneic iPSC-based cell therapies and their potential to alleviate human diseases.

关键词： mechanisms programming holds

Design and mechanical properties analysis of a cellular Waterbomb origami structure

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 193-202页

作者： Yongtao Bai Zhaoyu Wang Yu shi School of Civil Engineering Chongqing UniversityChongqing 400045China Research Center of Steel Structure Engineering Chongqing UniversityChongqing 400045China

Cellular structures are commonly used to design energy-absorbing structures,and origami structures are becominga prevalent method of cellular structure *** paper proposes a foldable cellular structure based on theWaterbomb origami *** geometrical configuration of this structure is ***-static compressiontests of the origami tube cell of this cellular structure are conducted,and load-displacement relationship curvesare *** simulations are carried out to analyze the effects of aspect ratio,folding angle,thicknessand number of layers of origami tubes on initial peak force and specific energy absorption(SEA).Calculationformulas for initial peak force and SEA are obtained by the multiple linear regression *** degree ofinfluence of each parameter on the mechanical properties of the single-layer tube cell is *** resultsshow that the cellular structure exhibits negative stiffness and periodic load-bearing capacity,as well as foldingangle has the most significant effect on the load-bearing and energy-absorbing *** adjusting the designparameters,the stiffness,load-bearing capacity and energy absorption capacity of this cellular structure can beadjusted,which shows the programmable mechanical properties of this cellular *** foldability andthe smooth periodic load-bearing capacity give the structure potential for application as an energy-absorbing structure.

关键词： Cellular structure Waterbomb origami Mechanical metamaterial Numerical simulation Energy absorption

Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： Han-Qing shi Hai-Qing Zhang Center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body *** they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural *** address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising ***,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field *** excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink ***,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the ***,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： Ye TIAN Tielin shi Qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

A modified smoothed particle hydrodynamics method considering residual stress for simulating failure and its application in layered rock mass

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Journal of Mountain Science 2024年第6期21卷 2091-2112页

作者： XIA Chengzhi shi Zhenming KOU Huanjia Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Residual strength is an indispensable factor in evaluating rock fracture,yet the current Smoothed Particle Hydrodynamics(SPH)framework rarely considers its influence when simulating *** improved cracking strategy considering residual stress in the base bond SPH method was proposed to simulate failures in layered rocks and slopes and verified by experimental results and other simulation methods(i.e.,the discrete element method).Modified Mohr–Coulomb failure criterion was applied to distinguish the mixed failure of tensile and *** fracture markψwas introduced to improve the kernel function after tensile damage,and the calculation of residual stress after the damage was derived after shear *** simulations were carried out to evaluate its performance under different stress and scale conditions and to verify its effectiveness in realistically reproducing crack initiation and propagation and coalescence,even fracture and *** results indicate that the improved cracking strategy precisely captures the fracture and failure pattern in layered rocks and rock *** residual stress of brittle tock is correctly captured by the improved SPH *** improved SPH method that considers residual strength shows an approximately 13%improvement in accuracy for the safety factor of anti-dip layered slopes compared to the method that does not consider residual strength,as validated against analytical *** infer that the improved SPH method is effective and shows promise for applications to continuous and discontinuous rock masses.

关键词： Smoothed particle hydrodynamics Cracking strategy Residual stress Layered rock Crack propagation

THE SCHUR TEST OF COMPACT OPERATORS

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Acta Mathematica Scientia 2024年第5期44卷 2041-2050页

作者： Qijian kang Maofa WANG School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang524048China School of Mathematics and Statistics Wuhan UniversityWuhan430072China

Infinite matrix theory is an important branch of function *** linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of the space,but not every infinite matrix corresponds to an *** classical Schur test provides an elegant and useful criterion for the boundedness of linear operators,which is considered a respectable mathematical *** this paper,we prove the compact version of the Schur ***,we provide the Schur test for the Schatten class S_(2).It is worth noting that our main results can be applicable to the general matrix without limitation on non-negative *** finally provide the Schur test for compact operators from l_(p) into l_(q).

关键词： Schur test compact operator infinite matrix