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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na Li Mai-he Li Yu Cong Haibo Du Decai Gao Hong s.he Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China school of Natural Resources University of MissouriColumbiaMO65211USA swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China school of Life science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TsAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TsALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NsC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TsAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TsAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TsAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TsAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NsC) Non-treeline species sink activity stressful environments Upper elevation limit

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Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/Fes nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

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Journal of Environmental sciences 2024年第2期136卷 390-399页

作者： Aihua Cheng Yi he Xiaohe Liu Chi he Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China state Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater ***,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/Fes(Fe/s)nanoparticles,was synthesized by simple impregnation precursor,followed by *** prepared Fe/s-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the ***,the acid microenvironment formed by sO_(4)^(2-)group from Fe/s composite extended the pH range for Fenton reaction,and s^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation ***,biochar can effectively promote cycling stability by limiting Fe *** work may provide a general strategy for designing 3D framework biochar-based Fe/s catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/Fes(Fe/s) Phenol degradation

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Plant type effect overweighs seasonal variation in n-alkanoic acid biomarker on regional Loess Plateau of China

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science China Earth sciences 2024年第8期67卷 2547-2562页

作者： Jinzhao LIU s.Nemiah LADD Jiaju ZHAO Dongna YAN Ding he Yunning CAO Zhisheng AN state Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAs Center for Excellence in Quaternary science and Global Change Xi’an 710061China Department of Environmental sciences University of BaselBasel 4056Switzerland Department of Ocean science and Center for Ocean Research in Hong Kong and Macao The Hong Kong University of Science and TechnologyHong Kong 999077China

The effect of plant type on n-alkane biomarker has been widely studied,but the influence of plant type on n-alkanoic acids(n-FAs)has received less *** the effect of the distribution of n-FAs and their hydrogen isotope composition(δ^(2)H_(FA))is critical for interpreting sedimentaryδ^(2)H_(FA)values as proxies of hydroclimate and/or vegetation *** this study,we systematically investigated the distribution ofn-FAs andδ^(2)H_(FA)values across seasons on the Chinese Loess Plateau(CLP).Our results showed that there were no significant seasonal differences in n-FAs distribution andδ^(2)H_(FA)values,but there were significant differences inδ^(2)H_(FA)values across plant ***δ^(2)H_(FA)values ranged from-185‰to-125‰in dicots(-161‰±28‰),and from-215‰to-170‰in monocots(-196‰±22‰)on the *** fractionation betweenδ^(2)H_(FA)values and precipitationδ^(2)H(ε_(FA-P))was also^(2)H-enriched in dicots relative to *** the regional scale of the CLP,δ^(2)H_(FA)values were not correlated withδ^(2)H values of ***,δ^(2)H_(FA)values from the CLP were similar to expectations from a global comparison,both in terms of their mean values and high variability among plants growing in sites with similarδ^(2)H values of *** some of this variability inεFA-Pis due to the effect of plant type,a careful assessment of the likely sources of waxes in terrestrial sediments is critical when usingδ^(2)H_(FA)values for paleohydroclimate reconstruction.

关键词： n-Alkanoic acid Hydrogen isotope Plant type Paleohydroclimate Chinese Loess Plateau

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Chemotherapy induces breast cancer stem cell enrichment through repression of glutathione s-transferase Mu

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Genes & Diseases 2024年第2期11卷 528-531页

作者： Jing he Yiran Yu Yilin he Jie he Guangyu Ji Haiquan Lu The second Hospital and Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Department of Nursing The First Affiliated Hospital of Shandong First Medical UniversityJinanShandong 250014China school of Medicine Xinjiang Medical UniversityUrumqiXinjiang 830054China school of Medicine Binzhou Medical UniversityYantaiShandong 264003China Oncology Department Jinan Zhangqiu District People's HospitalJinanShandong 250200China Key Laboratory for Experimental Teratology of the Ministry of Education Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Center for Reproductive Medicine Shandong UniversityJinanShandong 250012China

Triple-negative breast cancer(TNBC)has aggressive characteristics as exemplified by the high risk of recurrence,metastasis,and patient mortality.1 Cytotoxic chemotherapy may reduce tumor burden initially,but leave behind chemo-resistant breast cancer stem cells(BCsCs)that lead to tumor recurrence and metastasis.2 Chemotherapy induces BCsC enrichment through the activation of glutathione biosynthesis pathways,which increases intracellular glutathione levels and specifies the BCsC phenotype through complicated downstream signaling pathways.3 Glutathione s-transferases(GsTs),a superfamily(which contains seven cytosolic classes:Alpha,Kappa,Mu,Omega,Pi,Theta,and Zeta,and one microsomal class MGsTs)of phase Il enzymes that catalyze the conjugation of glutathione with electrophilic compounds,play a critical role in detoxification and chemotherapy resistance of cancer ***,the role of GsTs in the regulation of BCsCs is largely elusive.

关键词： chemotherapy breast metastasis

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P2P Energy Trading Considering Prosumer Preference and system Risk

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CsEE Journal of Power and Energy systems 2024年第3期10卷 1179-1194页

作者： Xinyu he Ping Dong Mingbo Liu Xuewei Huang Wenli Deng Ruijin he school of Electric Power Engineering South China University of TechnologyGuangzhou 510640China IEEE

As an important means of mobilizing demand-side resources,peer-to-peer(P2P)energy trading has drawn more and more attention from *** paper constructs a P2P energy trading framework considering prosumers’trading partner preferences(TPPs)and system *** first,we build the P2P trading models of prosumers equipped with different distributed energy resources(DERs),and TPP ***,to solve the established energy trading problem,a fully distributed double-consensus alternating direction method of multipliers(DC-ADMM)is proposed,which can achieve transaction consensus when considering market players’***,a risk-based security constrained economic dispatch(RBsCED)model based on AC power flow is established for the first time,by which a distribution system operator(DsO)checks system security and obtains risk-based locational marginal prices(RLMPs).Moreover,double-regulated price signals related to RLMPs which contain grid utilization prices(GUPs)and DsO’s retail prices realize management of players’*** the end,the proposed method is applied to an IEEE33 bus distribution *** show the proposed method effectively reduces system risk and ensures secure operation of system without direct management.

关键词： Double-consensus ADMM grid utilization price price signal risk-based locational marginal price trading partner preference

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Chien-physics-informed neural networks for solving singularly perturbed boundary-layer problems

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1467-1480页

作者： Long WANG Lei ZHANG Guowei he The state Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China school of Engineering sciences University of Chinese Academy of SciencesBeijing 100049China

A physics-informed neural network(PINN)is a powerful tool for solving differential equations in solid and fluid ***,it suffers from singularly perturbed boundary-layer problems in which there exist sharp changes caused by a small perturbation parameter multiplying the highest-order *** this paper,we introduce Chien's composite expansion method into PINNs,and propose a novel architecture for the PINNs,namely,the Chien-PINN(C-PINN)*** novel PINN method is validated by singularly perturbed differential equations,and successfully solves the wellknown thin plate bending *** particular,no cumbersome matching conditions are needed for the C-PINN method,compared with the previous studies based on matched asymptotic expansions.

关键词： physics-informed neural network(PINN) singular perturbation boundarylayer problem composite asymptotic expansion

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Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun Chen sheng-ping he College of Materials science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials science and Engineering Chongqing UniversityChongqing 400044China

single argon bubble dynamics in liquid steel under Ruhrstahl-heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

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Answering reachability queries with ordered label constraints over labeled graphs

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Frontiers of Computer science 2024年第1期18卷 105-117页

作者： Daoliang he Pingpeng YUAN Hai JIN National Engineering Research Center for Big Data Technology and system Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science&TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Reachability query plays a vital role in many graph analysis *** researches proposed many methods to efficiently answer reachability queries between vertex *** many real graphs are labeled graph,it highly demands Label-Constrained Reachability(LCR)query inwhich constraint includes a set of labels besides vertex *** researches proposed several methods for answering some LCR queries which require appearance of some labels specified in constraints in the *** that constraint may be a label set,query constraint may be ordered labels,namely OLCR(Ordered-Label-Constrained Reachability)queries which retrieve paths matching a sequence of ***,no solutions are available for ***,we propose DHL,a novel bloom filter based indexing technique for answering OLCR *** can be used to check reachability between vertex *** the answers are not no,then constrained DFs is ***,we employ DHL followed by performing constrained DFs to answer OLCR *** show that DHL has a bounded false positive rate,and it's powerful in saving indexing time and *** experiments on 10 real-life graphs and 12 synthetic graphs demonstrate that DHL achieves about 4.8-22.5 times smaller index space and 4.6-114 times less index construction time than two state-of-art techniques for LCR queries,while achieving comparable query response *** results also show that our algorithm can answer OLCR queries effectively.

关键词： graph ordered-label-constrained reachability partial index bloom filter query processing

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study on a semi-resolved CFD-DEM method for rod-like particles in a gas-solid fluidized bed

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Particuology 2024年第4期87卷 20-36页

作者： Liping he Zhengxian Liu Yongzhi Zhao Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin300350China Insttute of Process quipment College of Energy EngineeringZhejiang UniversityHangzhou30027China

Based on a semi-resolved CFD-DEM coupling method,this study proposed a method that uses the minimum distance between the fluid grid and the particle boundary as a reference value to determine the degree of influence of the target fluid grid on the particle's drag force.A fluidized bed of rod-like particles was chosen as a typical case to investigate the effect of different fluid grid scales on various fluidized bed characteristic *** calculation performance of the semi-resolved and unre-solved CFD-DEM coupling algorithm on key fluidized bed characteristic parameters such as average pressure drop,particle frequency distribution with bed height,and particle orientation distribution were *** was found that the semi-resolved CFD-DEM coupling algorithm gradually obtained results with higher consistency with decreasing fluid grid scale for key parameters such as particle frequency distribution with bed height,particle orientation distribution,and time-history mixing index,exhibiting a phenomenon similar to grid independence in fluid *** comparing with experimental results,it was verified that the semi-resolved CFD-DEM coupling algorithm can be applied to simulate multi-granular gas-solid systems with fluid grid scales equivalent to particle *** algorithm solves the limitation of fluid grid scale in the unresolved CFD-DEM coupling framework and improves the grid adaptability of the CFD-DEM coupling simulation algorithm.

关键词： CFD-DEM semi-resolved method Fluid-solid flow Non-spherical particle Fluidized bed

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On n-universal quadratic forms over dyadic local fields

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science China Mathematics 2024年第7期67卷 1481-1506页

作者： Zilong he Yong Hu school of Computer science and Technology Dongguan University of TechnologyDongguan523808China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China

Let n≥2 be an integer. We give necessary and sufficient conditions for an integral quadratic form over dyadic local fields to be n-universal by using invariants from Beli's theory of bases of norm ***, we provide a minimal set for testing n-universal quadratic forms over dyadic local fields, as an analogue of Bhargava and Hanke's 290-theorem(or Conway and schneeberger's 15-theorem) on universal quadratic forms with integer coefficients.

关键词： integral quadratic forms n-universal quadratic forms dyadic fields 290-theorem

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