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Nuclear Science and Techniques 2021年第4期32卷 10-19页

作者： feng Tian Chang-Ran Geng Xiao-Bin Tang Di-Yun Shu huang-feng ye Silva Bortolussi Chun-Hui Gong Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Nuclear Technology Application and Radiation Protection in Astronautics(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 210016China Unit of Pavia National Institute of Nuclear Physics(INFN)Via A.Bassi 627100 PaviaItaly

A method based on the cross-sectional relationship between^(10)B(n,α)^(7)Li and^(1)H(n,γ)^(2)H was proposed to detect and reconstruct the three-dimensional boron concentration/dose distribution in vivo during boron neutron capture therapy(BNCT).Factors such as the neutron energy,fluence rate,and degree of non-uniform distribution of the boron concentration in a voxel may affect the results of this method.A theoretical analysis of the accuracy of the method using a Monte Carlo simulation shows that the determining error is generally less than 1%under different tumor locations and neutron source *** the voxel size is larger than 0.4 cm,the determining error might be higher for a non-uniformly distributed boron concentration in the voxel because of the changes in the neutron energy and fluence *** conclusion,the proposed method enables an accurate threedimensional boron determination in vivo during BNCT.

关键词： BNCT Boron concentration Prompt gamma Capture cross section

Noninvasive beam diagnosis based on the TM_(010)mode

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Nuclear Science and Techniques 2024年第7期35卷 115-125页

作者： Chuang-ye Song Wen-Hui huang Department of Engineering Physics Tsinghua University BeijingBeijing100084China of Education Beijing100084China

A resonant cavity based on the TM_(010)mode is an effective tool for noninvasive beam characterization. This technique has the advantages of a high signal-to-noise ratio, compact structure, and is related to multiple parameters compared with other beam monitors. In this study, high-precision measurements of the bunch charge, arrival time, bunch length, and energy parameters based on the TM_(010)mode are discussed. A cavity beam arrival time monitor(BAM) utilizing a phase cavity has been widely used in many facilities. Regarding bunch-length measurements, the influence of the beam energy, beam offset,and longitudinal spectrum on the TM_(010)mode are carefully considered to reduce errors, and the theoretical resolution of two cavities with different frequencies is analyzed. Owing to the dependence of the beam velocity of the beam loss factor, this method can also be used for the detection low beam energy using two cavities with the same frequency but different cavity lengths. A set of three cavities with different lengths and frequencies of 1.902 and 11.424 GHz is presented for measuring the four aforementioned parameters.

关键词： TM_(010)mode Noninvasive diagnosis Beam length Low energy

Energy-information trade-off induces continuous and discontinuous phase transitions in lateral predictive coding

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 79-85页

作者： Zhen-ye huang Ruyi Zhou Miao huang Hai-Jun Zhou Key Laboratory for Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China Minjiang Collaborative Center for Theoretical Physics Minjiang UniversityFuzhou 350108China

Lateral predictive coding is a recurrent neural network that creates energy-efficient internal representations by exploiting statistical regularity in sensory ***,we analytically investigate the trade-off between information robustness and energy in a linear model of lateral predictive coding and numerically minimize a free energy *** observed several phase transitions in the synaptic weight matrix,particularly a continuous transition that breaks reciprocity and permutation symmetry and builds cyclic dominance and a discontinuous transition with the associated sudden emergence of tight balance between excitatory and inhibitory *** optimal network follows an ideal gas law over an extended temperature range and saturates the efficiency upper bound of energy *** results provide theoretical insights into the emergence and evolution of complex internal models in predictive processing systems.

关键词： predictive coding recurrent neural network phase transition internal model free energy

Estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy

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International Journal of Mining Science and Technology 2024年第2期34卷 137-148页

作者： Chuangbing Zhou Zuyang ye Chi Yao Xincheng Fan feng Xiong School of Infrastructure Engineering Nanchang UniversityNanchang 330031China b School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Engineering China University of GeosciencesWuhan 430074China

With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different *** with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture *** to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip *** a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors.

关键词： 3D fracture network Geological entropy Directional entropic scale Anisotropy Hydraulic conductivity

Ultralow friction PTFE/PEEK heterolayer:A new solid lubrication approach toward simplicity

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Friction 2024年第1期12卷 120-135页

作者： Wei SUN Jiaxin ye Qingrui SONG Yi feng Xiaojun LIU School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Institute of Tribology School of Mechanical EngineeringHefei University of TechnologyHefei 230009China

Tribological applications of polytetrafluoroethylene(PTFE)are often limited by technological complexity to overcome its poor wear ***,a PTFE/polyetheretherketone(PEEK)heterolayer(HL)was proposed and evaluated as a new solid lubrication ***-on-disk tribometry found the lowest friction coefficient(μ)of 0.031 and ultralow wear for the PEEK/HL under typical *** friction coefficient of the HL surpasses those of the state-of-the-art polymeric coatings/composites by at least 200%,and approaches that of highly lubricated *** investigations revealed multi-length physical and chemical heterogeneity of the HL that best facilitates a tribofilm with high subsurface stability and surface *** technological simplicity and robustness of the HL’s high lubricity make it a promising new type of solid lubrication toward greater reliability and longevity.

关键词： ultralow friction anti-wear polytetrafluoroethylene(PTFE) heterolayer(HL)

Joint deletion of multifunctional MGF505-7R and H240R genes generates a safe and effective African swine fever virus attenuated live vaccine candidate

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Virologica Sinica 2024年第3期39卷 355-357页

作者： Changjiang Weng Li huang Guangqiang ye Division of Fundamental Immunology National African Swine Fever Para-reference LaboratoryState Key Laboratory for Animal Disease Control and PreventionHarbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China Heilongjiang Provincial Key Laboratory of Veterinary Immunology Harbin 150069China

African swine fever(ASF)caused by the ASF virus(ASFV)is a highly contagious disease of pigs and wild ***,there are no safe,effective commercial vaccines *** genome of ASFV HLJ/18 contains more than 180 genes,including a few virulence-related *** these key virulence genes through individual deletion and subsequent pathogenicity testing in pigs is a laborious *** addition,some ASFV genes are indispensable for viral replication and cannot be *** the past 30 years,scientists have confirmed that certain ASFV genes particularly those host antiviral innate immune responses,are associated with the virulence of ASFV *** knockout of these genes does not impact viral replication,it does attenuate the virulence of ASFV in *** immunized with these live attenuated vaccine candidates can provide partial or complete *** on these findings,we propose a new concept that ASFV immunomodulatory genes involved in type I interferon(IFN)production,IFN-JAK-STAT signaling,inflammatory responses,cell death(involved in apoptosis,necrosis,and pyroptosis),and autophagy may be related to the pathogenicity of *** unbiased screening may identify more ASFV immunomodulatory or multifunctional genes,simplifying the confirmation of ASFV virulence-related *** line with these theories,we have identified MGF505-7R and H240R as key virulence genes determining the pathogenicity of the ASFV HLJ/18 *** of MGF505-7R,H240R alone or both attenuate the virulence of ASFV HLJ/18 in pigs,providing a paradigm for developing attenuated live vaccines from basic research results.

关键词： attenuated fever swine

The Extension Dimension of Subcategories and Recollements of Abelian Categories

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1042-1058页

作者： Xin MA ye Yang PENG Zhao Yong huang College of Science Henan University of EngineeringZhengzhou 451191P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

We investigate the behavior of the extension dimension of subcategories of abelian categories under ***Λ',Λ,Λ"be art in algebras such that(modΛ',mod A,modΛ")is a recollement,and let D'and D"be subcategories of modΛand modΛ"*** any n,m≥0,under some conditions,we get dimΩ^(k)(D)≤dimΩ^(n)(D')+dimΩ^(m)(D")+1,where k=max{m,n}and D is the subcategory of modΛglued by D'and D";moreover,we give a sufficient condition such that the converse inequality holds *** applications,some results for Igusa-Todorov subcategories and syzygy finite sub categories are obtained.

关键词： Recollements extension dimension Igusa–Todorov subcategories syzygy finite subcategories

A Blockchain and CP-ABE Based Access Control Scheme with Fine-Grained Revocation of Attributes in Cloud Health

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Computers, Materials & Continua 2024年第2期78卷 2787-2811页

作者： ye Lu Tao feng Chunyan Liu Wenbo Zhang School of Computer&Communication Lanzhou University of TechnologyLanzhou730000China School of Economics&Management Lanzhou University of TechnologyLanzhou730000China School of Computer Science Baoji University of Arts and ScienceBaoji721000China

The Access control scheme is an effective method to protect user data *** access control scheme based on blockchain and ciphertext policy attribute encryption(CP–ABE)can solve the problems of single—point of failure and lack of trust in the centralized ***,it also brings new problems to the health information in the cloud storage environment,such as attribute leakage,low consensus efficiency,complex permission updates,and so *** paper proposes an access control scheme with fine-grained attribute revocation,keyword search,and traceability of the attribute private key distribution *** technology tracks the authorization of attribute private *** credit scoring method improves the Raft protocol in consensus ***,the interplanetary file system(IPFS)addresses the capacity deficit of *** the premise of hiding policy,the research proposes a fine-grained access control method based on users,user attributes,and file *** optimizes the data-sharing *** the same time,Proxy Re-Encryption(PRE)technology is used to update the access *** proposed scheme proved to be *** analysis and experimental results show that the proposed scheme has higher efficiency and more *** can meet the needs of medical institutions.

关键词： Blockchain access-control CP-ABE cloud health

A Large-Scale Online Survey on Clinical Severity and Associated Risk Factors for SARS-CoV-2 Omicron Infection — China, April–May 2023

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China CDC weekly 2024年第15期6卷 305-311,I0001-I0004页

作者： Yanxia Sun Yuping Duan Jie Qian Yimin Qu ye Wang Guohui Fan Qiangru huang Zhongjie Li Weizhong Yang Luzhao feng State Key Laboratory of Respiratory Health and Multimorbidity Key Laboratory of Pathogen Infection Prevention and ControlMinistry of EducationSchool of Population Medicine and Public HealthChinese Academy of Medical Science&Peking Union Medical CollegeBeijingChina

What is already known about this topic?Individuals who initially contract severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)lack significant mixed ***,it is crucial to monitor the clinical characteristics and associated factors of these individuals in order to inform *** is added by this report?The common symptoms reported were fever,cough,and sore *** and receiving four vaccination doses within a 6-month period were found to be associated with a shorter duration of virus shedding,decreased hospitalization rate,and reduced risk of *** aged 60 years and older,as well as those with underlying medical conditions,had a higher risk of developing *** are the implication for public health practices?Online surveys conducted through social media platforms have the potential to complement disease surveillance and data collection *** terms of vaccination prioritization,it is recommended to prioritize older individuals and those with underlying diseases.

关键词： doses Online initially

Occurrence of dark septate endophytes in Phragmites australis in the Baiyang Lake and their resistance to Cd stress

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Pedosphere 2024年第2期34卷 484-496页

作者： Minghui XU Xia LI Qiannan ye feng GONG Xueli HE School of Life Sciences Hebei UniversityBaoding 071002China Key Laboratory of Microbial Diversity Research and Application of Hebei Province Hebei UniversityBaoding 071002China

Heavy metal pollution poses a serious hazard to human health,and microbial remediation of heavy metals in soil has been widely studied.A group of ascomycetes classified as dark septate endophytes(DSEs)colonize plant roots and benefit host plants under abiotic stress *** this study,Phragmites australis,a common remediation plant in the Baiyang Lake in North China,was *** and roots of *** were collected in typical heavy metal-contaminated sites,and the species diversity and community structure of DSEs in *** roots were *** addition,DSE strains were isolated,cultured,and tested for their tolerance to Cd *** results showed that DSEs occurred extensively in *** roots,forming typical dark septate hyphae,with a total colonization rate of 19.7%–83.1%.Morphological and internal transcribed spacer sequencing analyses were used to identify 10 species within 9 genera of DSE *** these fungi,6 strains with considerable resistance to Cd stress were *** biomasses of Poaceascoma helicoides,Alternaria doliconidium,and Acrocalymma vagum strains increased as the Cd levels *** results can not only help to understand plant-DSE interactions in wetland environments,but also provide a theoretical basis for making full use of DSE fungi to alleviate heavy metal contamination in soil.

关键词： ascomycete colonization rate contaminated site evenness index heavy metal Shannon-Wiener index Simpson index wetland