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Forest Ecosystems 2024年第5期11卷 677-684页

作者： Richard Osei Lance p.Moore Rosanise A.Odell Marcel Schneider Tanvir Ahmed Shovon charles A.Nock Department of Renewable Resources University of AlbertaEdmontonCanada Institut des Sciences de La For^et Temperee Universite Du Quebec en Outaouais58 Rue PrincipaleRiponJ0V 1V0QCCanada

In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests,ecosystem-based forest management(EBM)has become the de facto management *** forestry represents one prominent way that EBM is implemented in many parts of the *** patches commonly left after harvesting serve as analogues of fire island remnants,which are patches of unburned forests in the burned forest *** the persistence of retention patches has been questioned,few studies have attempted to quantitatively compare forest attributes in both burned and harvested *** part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants,we investigated the impact of disturbance type(fire/harvest)and forest edges on C stock in snags and coarse woody debris(CWD)found in island remnants in mixedwood boreal forests of Alberta,*** C stock(in snags and CWD)was similar between the two disturbance types and edge plots had similar total deadwood C stocks to *** edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types,but C stock in CWD was unaffected by edge effects and disturbance *** results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar,thus lending support for the continued implementation of retention forestry in Alberta.

关键词： Retention forestry Deadwood Ecosystem-based management Wildfires Boreal forest

The Enhanced period Map and Equivariant Deformation Quantizations of Nilpotent Orbits

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Acta Mathematica Sinica,English Series 2024年第3期40卷 885-934页

作者： Shi lin YU Department of Mathematics School of Mathematical SciencesXiamen UniversityXiamen 361005P.R.China

In a previous paper,the author and his collaborator studied the problem of lifting Hamil-tonian group actions on symplectic varieties and Lagrangian subvarieties to their graded deformation quantizations and apply the general results to coadjoint orbit method for semisimple Lie *** even quantizations were considered *** this paper,these results are generalized to the case of general quantizations with arbitrary *** key step is to introduce an enhanced version of the(truncated)period map defined by Bezrukavnikov and Kaledin for quantizations of any smooth sym-plectic variety X,with values in the space of picard Lie algebroid over *** an application,we study quantizations of nilpotent orbits of real semisimple groups satisfying certain codimension condition.

关键词： Coadjoint orbit method deformation quantization Harish-Chandra modules semisimple Liegroups

Mechanism study of Cu(Ⅱ) adsorption from acidic wastewater by ultrasonic-modified municipal solid waste incineration fly ash

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Chinese Journal of Chemical Engineering 2024年第3期67卷 157-165页

作者： Shunda lin Yang Lu lin Zheng ling Long Xuguang Jiang Jianhua Yan State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China Zhejiang University Qingshanhu Energy Research Center Hangzhou 310027China Hangzhou Xiaoshan Jinjiang Green Energy Co. Ltd.XiaoshanHangzhou 310000China

High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG ption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects.

关键词： Ultrasound MSWI fly ash Cu(Ⅱ) Wastewater Adsorption

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin Shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code pRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

A new elastoplastic model for bolt-grouted fractured rock

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International Journal of Mining Science and Technology 2024年第7期34卷 995-1016页

作者： Haoyi Li Shuangying Zuo peiyuan lin State Key Laboratory for Tunnel Engineering Sun Yat-Sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519082China School of Civil Engineering Sun Yat-Sen UniversityGuangzhou 510275China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Complexities in mechanical behaviours of rock masses mainly stem from inherent discontinuities,which calls for advanced bolt-grouting techniques for stability *** the mechanical properties of bolt-grouted fractured rock mass(BGFR)and developing accurate prediction methods are crucial to optimize the BGFR support *** paper establishes a new elastoplastic(E-p)model based on the orthotropic and the Mohr-Coulomb(M-C)plastic-yielding *** elastic parameters of the model were derived through a meso-mechanical analysis of composite materials mechanics(CMM).Laboratory BGFR specimens were prepared and uniaxial compression test and variable-angle shear test considering different bolt arrangements were carried out to obtain the mechanical parameters of the *** showed that the anisotropy of BGFR mainly depends on the relative volume content of each component material in a certain ***,the mechanical parameters deduced from the theory of composite materials which consider the short fibre effect are shown to be in good agreement with those determined by laboratory experiments,and the variation rules maintained good ***,a case study of a real tunnel project is provided to highlight the effectiveness,validity and robustness of the developed E-p model in prediction of stresses and deformations.

关键词： Bolt-grouted fractured rock mass Elastoplastic model Composite materials mechanics Laboratory experiment

An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-Time Switched LQR problem

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Journal of Systems Science & Complexity 2024年第1期37卷 22-39页

作者： HOU Tan LI Yuanlong lin Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR *** particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value *** method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing *** numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

Distribution of per-and polyfluoroalkyl substances in blood,serum,and urine of patients with liver cancer and associations with liver function biomarkers

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Journal of Environmental Sciences 2024年第5期139卷 418-427页

作者： Cao Dai lin peng Yanjie Li Zhendong Li Da Chen Fei Wang Nan lin Department of Hepatobiliary Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630China School of Environment Guangdong Key Laboratory of Environmental Pollution and HealthJinan UniversityGuangzhou 510632China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China South China Institute of Environmental Sciences MEEGuangzhou 510655China

Studies have shown that per-and polyfluoroalkyl substances(pFASs)may be hepatotoxic in animals or ***,data on clinical epidemiology are very *** this study,21pFASs were determined in patients with liver diseases,with the highest median concentrations detected in the serum sample(26.7 ng/mL),followed by blood(10.7 ng/mL)and urine(5.02 ng/mL).Higher total pFAS concentrations were found in hepatocellular carcinoma(HCC)patients compared to non-HCC patients,with significant discrepancies in serum and blood ***,significant correlations were also found among pFAS concentrations and age,gender,body mass index(BMI),and liver function biomarkers *** example,pFAS concentrations are significantly higher in males than in females;Several serum pFASs concentrations increase with age and BMI,while the serum perfluorohexane sulfonic acid(pFHxS)concentrations are negatively correlated with *** addition,multiple regression models adjusted for age,gender and BMI found that increased serum perfluorobutane sulfonic acid(pFBS),perfluoroheptane sulfonic acid(pFHpS)and perfluorohexylphosphonic acid(pFHxpA)conentrations are correlated with elevated alkaline phosphatase(ALp),aspartate aminotransferase(AST),and alpha-fetoprotein(AFp)(pprovide epidemiological support for the future study on the potential clinical hepatotoxicity of pFAS.

关键词： per-and polyfluoroalkyl substances(pFASs) Liver cancer Serum Blood Urine Liver function biomarkers

The Minimum Centroid Branch Spanning Tree problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao lin Cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly Np-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and p_(m)×p_(n),are presented.

关键词： Spanning tree optimization Centroid branch-Np-hardness polynomial-time algorithm

Half a century after their discovery:Structural insights into exonuclease and annealase proteins catalyzing recombineering

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Engineering Microbiology 2024年第1期4卷 39-54页

作者： Lucy J.Fitschen Timothy p.Newing Nikolas p.Johnston charles E.Bell Gökhan Tolun School of Chemistry and Molecular Bioscience and Molecular HorizonsUniversity of WollongongWollongongNSWAustralia The ARC Training Centre for Cryo-electron Microscopy of Membrane proteins University of WollongongWollongongNSWAustralia Faculty of Science University of Technology SydneyUltimoNSW 2007Australia Department of Biological Chemistry and pharmacology The Ohio State University College of MedicineColumbusOH 43210

Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations involving restriction *** main workhorses behind recombineering are bacteriophage proteins that promote the single-strand annealing(SSA)homologous recombination pathway to repair double-stranded DNA *** there have been several reviews examining recombineering methods and applications,comparatively few have focused on the mechanisms of the proteins that are the key players in the SSA pathway:a 5′→3′exonuclease and a single-strand annealing protein(SSAp or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be developed for recombineering in ***:the RecET system from *** Rac prophage and the𝜆Red system from bacteriophageλ.By comparing the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we provide new insights into how the structures of these proteins dictate their *** the sequence conservation of the𝜆λExo and RecE exonucleases gives more profound insights into their critical functional ***,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the proteins behind this powerful technique will drive the development of improved and expanded capabilities in the future.

关键词： Recombineering Redβ λExo RecE RecT protein structure Annealase Exonuclease

Boundary Behaviors for a Continuous-state Nonlinear Neveu’s Branching process

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2005-2016页

作者： lin Yu BAI Xu YANG School of Mathematics and Information Science North Minzu UniversityYinchuan 750021P.R.China

By generalizing a criterion of Mufa Chen for Markov jump processes,we establish the necessary and sufficient conditions for the extinction,explosion and coming down from infinity of a continuous-state nonlinear Neveu... 详细信息

关键词： Continuous-state branching process nonlinear branching Neveu’s branching extinction explosion coming down from infinity