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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 27-83页

作者： Ling-hai ZHANG Department of Mathematics Lehigh UniversityBethlehemPA 18015 USA

We couple together existing ideas,existing results,special structure and novel ideas to accomplish the exact limits and improved decay estimates with sharp rates for all order derivatives of the global weak solutions of the Cauchy problem for an n-dimensional incompressible Navier-Stokes *** also use the global smooth solution of the corresponding heat equation to approximate the global weak solutions of the incompressible Navier-Stokes equations.

关键词： the incompressible Navier-Stokes equations global smooth solution global weak solutions local smooth solutions all order derivatives special structure novel ideas primary decay estimates with sharp rates exact limits improved decay estimates with sharp rates influence on numerical simulations

Compositional Dynamics of Plant Functional Groups and Their Effects on Stability of Community ANPP During 17 yr of Mowing Succession on Leymus chinensis Steppe of Inner Mongolia, China

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Acta Botanica Sinica 2004年第10期46卷 1155-1162页

作者： baoya-jingl.lizheng-hai ZHONGYan-Kai LaboratoryofQuantitativeVegetationEcology InstituteofBotanyTheChineseAcademyofSciencesBeijing100093China InnovationBaseofRegionalEcologicalEnvironmentProtection ChineseResearchAcademyofEnvironmentalScienceBeijing100012China CollegeofLifeSciences InnerMongoliaUniversityHuhhot010021China

Using field experimental data of 17 yr of mowing succession of Leymus chinensis (Trin.) Tzvel. steppe of Inner Mongolia (Nei Mongol), we analyzed the dynamics of community composition based on plant functional groups (PFGs), explored the relationship between changes of the PFGs proportion in community and the community annual net primary production (ANPP), and examined the influences of structural parameters on functional parameters. Our results showed that during 17 yr of mowing succession, changes in both community structure and function took place. The roles of different PFGs varied appar-ently with mowing succession: the dominance of rhizome grasses was replaced successively by annuals and biennials, tall bunch grasses, and short bunch grasses. Following 17 yr of mowing, the community became codominated by rhizome grasses, tall bunch grass, and short bunch grass. ANPP correlated significantly with annual precipitation in control plot, but not in successive mowing plot. Annual precipita-tion explained more than 62% of the annual variability in ANPP of control plot, whereas annual variation of ANPP in mowing plot was mainly driven by successive mowing disturbance. The community ANPP showed resilience to mowing disturbance and kept relatively stable initially through internal regulation of PFGs, and declined to a lower level with structural changes of the community after about 5 yr, and then again maintained at a stable level through structural regulation. Therefore, in mowing succession the commu-nity structurere presented by PFGs changed gradually while the community function represented by ANPP declined abruptly. The community relied on constantly regulating the structure to maintain the function stability. The community function would degrade after its structure changed to certain degree.

关键词：草原内蒙古群落中国一年净初级产量

New Taub-NUT black holes with massive spin-2 hair

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 51-58页

作者： Yu-Qi Chen hai-Shan Liu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China

We consider Einstein gravity extended with quadratic curvature invariants,within which the well-known Ricci-flat Taub-NUT black hole remains a *** analysis of the unstable Lichnerowicz modes in the Taub-NUT background enables us to identify the mass and NUT parameters(m,n)where new Taub-NUT black holes can *** then adopt numerical techniques to construct these new Taub-NUT black holes,which bifurcate away from the Ricci-flat *** the Ricci-flat Taub-NUT,there can exist two new black holes for an appropriate given temperature,making it a total of three if we include the Ricci-flat one.

关键词： higher derivative gravity black hole solution Taub-NUT spacetime

Some Eigenvalue Properties of Third-order Boundary Value Problems with Distributional Potentials

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 179-199页

作者： hai-yan ZHANG Ji-jun AO College of Sciences Inner Mongolia University of TechnologyHohhot 010051China

Several eigenvalue properties of the third-order boundary value problems with distributional potentials are ***,we prove that the operators associated with the problems are self-adjoint and the corresponding eigenvalues are ***,the continuity and differential properties of the eigenvalues of the problems are given,especially we find the differential expressions for the boundary conditions,the coefficient functions and the ***,we show a brief application to a kind of transmission boundary value problems of the problems studied here.

关键词： third-order boundary value problems distributional potentials quasi-derivatives eigenvalues

HMGB2 knockdown ameliorates retinal ganglion cell injury by inhibiting NLRP3 inflammasome activation after retinal ischemia

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 39-50页

作者： Lin-Ping Xue hai-Song Feng Hubei University of Chinese Medicine Wuhan 430065Hubei ProvinceChina Department of Encephalopathy Hubei Provincial Hospital of Traditional Chinese MedicineWuhan 430070Hubei ProvinceChina

AIM:To explore the neuroprotective effects of high mobility group box 2(HMGB2)knockdown on retinal ganglion cells(RGCs)in the retinal ischemia-reperfusion injury(RIRI).METHODS:Oxygen-glucose deprivation(OGD)-injured RGCs from postnatal three-day C57BL/6 mice pups and high intraocular pressure(IOP)-induced RIRI mice were used as cellular and animal models of *** expression of HMGB2 in the retina of RIRI mice and OGD-injured RGCs was detected through reverse transcription-polymerase chain reaction(RT-qPCR)and Western *** effects of HMGB2 silencing on the morphological changes,RGCs survival,and cell apoptosis in mouse retinal tissues were observed through H&E staining,immunofluorescence staining with RNA-binding protein with multiple splicing(RBPMS)antibody,and TUNEL staining,*** viability and apoptosis were examined by CCK-8 and flow cytometry *** levels of proteins associated with NOD-like receptor thermal protein domain associated protein 3(NLRP3)-mediated pyroptosis[NLRP3,Caspase-1,GSDMD-N,interleukin(IL)-1β,IL-18]in vivo and in vitro were measured by Western ***:HMGB2 protein and NLRP3 were upregulated in the retina of RIRI mice and OGD-injured RGCs(P<0.001).The retina was edematous,accompanied by disorganized cell arrangement and decreased thickness of all layers,and obvious vacuoles in ganglion cell ***2 silencing alleviated the reduction in total retinal thickness and the severity of retinal tissue damage as well as suppressed RGC loss and retinal cell apoptosis in RIRI ***-induced RGC apoptosis was ameliorated after downregulation of HMGB2 in *** injection of the AAV-sh-HMGB2 and si-HMGB2 resulted in significantly decrease of NLRP3,Caspase-1,GSDMD-N,IL-1β,and IL-18 protein levels in the retinal tissues of RIRI mice and OGD-injured RGCs,respectively(all P<0.001).CONCLUSION:HMGB2 knockdown protects against RGC apoptosis and pyroptosis after RIRI through suppressing NLRP3 inflammasome activ

关键词： HMGB2 retinal ischemia-reperfusion injury retinal ganglion cell apoptosis pyroptosis NLRP3 mice

Bifurcations and Spatiotemporal Patterns in the Diffusive Nutrient-Microor ganism Model

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 162-178页

作者： Ya-di WANG hai-long YUAN Yan-ling LI School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China School of Mathematics and Information Science Shaanxi Normal UniversityXi'an 710062China

In this paper,the diffusive nutrient-microorganism model subject to Neumann boundary conditions is *** Hopf bifurcations and steady state bifurcations which bifurcate from the positive constant equilibrium of the system are investigated in *** addition,the formulae to determine the direction of Hopf and steady state bifurcations are *** results show the existence of spatially homogeneous/nonhomogeneous periodic orbits and steady state solutions,which indicates the spatiotemporal dynamics of the *** numerical simulations are also presented to support the analytical results.

关键词： nutrient-microorganism model Hopf bifurcation steady state bifurcation simulations

Potential dependence in electrocatalysis:a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming Xia Zeyu Wang Yinjuan Chen hai Xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

RE-SEGNN:recurrent semantic evidence-aware graph neural network for temporal knowledge graph forecasting

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Science China(Information Sciences) 2025年第2期68卷 103-119页

作者： Wenyu CAI Mengfan LI Xuanhua SHI Yuanxin FAN Quntao ZHU 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 and TechnologyHuazhong University of Science and Technology

Temporal knowledge graph(TKG) reasoning, has seen widespread use for modeling real-world events, particularly in extrapolation settings. Nevertheless, most previous studies are embedded models, which require both entity and relation embedding to make predictions, ignoring the semantic correlations among different entities and relations within the same timestamp. This can lead to random and nonsensical predictions when unseen entities or relations occur. Furthermore, many existing models exhibit limitations in handling highly correlated historical facts with extensive temporal depth. They often either overlook such facts or overly accentuate the relationships between recurring past occurrences and their current counterparts. Due to the dynamic nature of TKG, effectively capturing the evolving semantics between different timestamps can be *** address these shortcomings, we propose the recurrent semantic evidenceaware graph neural network(RE-SEGNN), a novel graph neural network that can learn the semantics of entities and relations simultaneously. For the former challenge, our model can predict a possible answer to missing quadruples based on semantics when facing unseen entities or relations. For the latter problem, based on an obvious established force, both the recency and frequency of semantic history tend to confer a higher reference value for the current. We use the Hawkes process to compute the semantic trend, which allows the semantics of recent facts to gain more attention than those of distant facts. Experimental results show that RE-SEGNN outperforms all SOTA models in entity prediction on 6 widely used datasets, and 5 datasets in relation prediction. Furthermore, the case study shows how our model can deal with unseen entities and relations.

关键词： knowledge graph reasoning temporal knowledge graph Hawkes process semantic evidence

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Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第1期68卷 186-191页

作者： hai Zou Yunfeng Bao Xueshang Xin Yu Qi Tengfeng Xie Fuxiang Zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029China College of Chemistry Jilin UniversityChangchun 130012China

Constructing typeⅡheterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated(oxy)nitrides with low thermal ***,we synthesized a homologous heterostructure(denoted as YTON_H)based on the oxynitrides of YTaO_(4-x)N_(y)and YTa ON_(2).This heterostructure exhibits type Ⅱ band structure alignment and intimate interface achieved through a magnesium(Mg)powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON_H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO_(4-x)N_(y)and YTaON_(2)).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light

Do Institutional Investor Cliques Undermine Stock Price Efficiency?

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China & World Economy 2025年第1期33卷 223-258页

作者： hai Jiang Shuangyi Chen Zifeng Wang School of Economics Jinan UniversityChina Dongguan Academy of Social Sciences China

This study investigates the effects of institutional investor cliques on stock price efficiency. Using a community network algorithm, it identifies cliques of institutional investors and finds that they significantly undermined stock price efficiency in China. The robustness of this finding is demonstrated through a range of methodologies, including the substitution of dependent variables, the alteration of estimation methods, the exclusion of data from extreme market periods, and the application of instrumental variables. The role of institutional investor cliques in diminishing market efficiency is attributed to market speculation. The detrimental effect of cliques on efficiency is exacerbated in environments characterized by low stock liquidity, poor information disclosure, and heightened panic among retail investors. However, regulatory interventions, such as inquiry letters, are shown to mitigate these effects and enhance market efficiency. These findings highlight the unexpected ways institutional investor cliques can influence emerging market economies and underscore the critical importance of effective regulation to safeguard market efficiency.

关键词： emerging market economics institutional investor clique stock pric efficiency