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NONMONOTONE LOCAL MINIMAX METHODS FOR FINDING MULTIPLE SADDLE POINTS

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Journal of Computational Mathematics 2024年第3期42卷 851-884页

作者： Wei Liu Ziqing Xie Wenfan yi South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631China Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) Hunan Normal UniversityChangshaHunan 410081China Hunan Provincial Key Laboratory of Intelligent Information Processing and Applied Mathematics School of MathematicsHunan UniversityChangshaHunan 410082China

In this paper,by designing a normalized nonmonotone search strategy with the BarzilaiBorwein-type step-size,a novel local minimax method(LMM),which is a globally convergent iterative method,is proposed and analyzed to find multiple(unstable)saddle points of nonconvex functionals in Hilbert *** to traditional LMMs with monotone search strategies,this approach,which does not require strict decrease of the objective functional value at each iterative step,is observed to converge faster with less ***,based on a normalized iterative scheme coupled with a local peak selection that pulls the iterative point back onto the solution submanifold,by generalizing the Zhang-Hager(ZH)search strategy in the optimization theory to the LMM framework,a kind of normalized ZH-type nonmonotone step-size search strategy is introduced,and then a novel nonmonotone LMM is *** feasibility and global convergence results are rigorously carried out under the relaxation of the monotonicity for the functional at the iterative ***,in order to speed up the convergence of the nonmonotone LMM,a globally convergent Barzilai-Borwein-type LMM(GBBLMM)is presented by explicitly constructing the Barzilai-Borwein-type step-size as a trial step-size of the normalized ZH-type nonmonotone step-size search strategy in each ***,the GBBLMM algorithm is implemented to find multiple unstable solutions of two classes of semilinear elliptic boundary value problems with variational structures:one is the semilinear elliptic equations with the homogeneous Dirichlet boundary condition and another is the linear elliptic equations with semilinear Neumann boundary *** numerical results indicate that our approach is very effective and speeds up the LMMs significantly.

关键词： Multiple saddle points Local minimax method Barzilai-Borwein gradient method Normalized nonmonotone search strategy Global convergence

Remarks on the Global Existence for Incompressible Navier-Stokes Equations

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Chinese Annals of Mathematics,Series B 2024年第4期45卷 529-536页

作者： Sheng WANG Zexian ZHANG yi ZHOU Shanghai Center for Mathematical Sciences Fudan UniversityShanghai 200433China School of Mathematics Science Fudan UniversityShanghai 200433China

In this article,the authors use the special structure of helicity for the threedimensional incompressible Navier-Stokes equations to construct a family of finite energy smooth solutions to the Navier-Stokes equations ... 详细信息

关键词： Navier-Stokes euqations Helicity Global existence Critical norm

Systematic and long-term technical validity of toxicity determination and early warning of heavy metal pollution based on an automatic water-toxicity-determination-system

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 59-71页

作者： Yue yi Baoguo Wang Xuemei yi Fan Zha Haisen Lin Zhijun Zhou Yanhong Ge Hong Liu School of Life Science Beijing Institute of TechnologyBeijing 100081China Institute of Environmental Biology and Life Support Technology School of Biological Science and Medical EngineeringBeihang UniversityBeijing 100191China Infore Environment Technology Group Foshan 528000China Jiangmen Ecological Environment Monitoring Station Jiangmen 529000China Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center Guangzhou 510000China

Water toxicity determination with electrochemically active bacteria(EAB)shows promise for providing early warnings for heavy metal pollution in ***,thus far,only idealized tests with a few types of heavy metals have been *** this study,an automatic water-toxicitydetermination system with high technical maturity was established,and the toxicological properties of common heavy metals were systematically *** results demonstrated that the common heavy metals linearly inhibited EAB currents in the range of 0.1 mg/L to 0.5 mg/*** toxicity ranking of the tested heavy metals was Pb^(2+)>Tl^(3+)>Cu^(2+)>Cd^(2+)>Zn^(2+)>Ni^(2+)>Hg^(2+)>As^(3+).The toxicity interaction mainly exhibited an antagonistic effect in binary heavy metal *** system can accurately determine surface water toxicity and rapidly monitor heavy metal pollution,with good repeatability and a long ***,this study demonstrates that EAB are capable of long-term(>60 d)surface water quality monitoring and on-site early warning of heavy metal pollution.

关键词： Biological early warning system Electrochemically active bacteria Water toxicity determination Biosensor Heavy metal pollution Early warning

AdaPIP: Adaptive picture-in-picture guidance for 360° film watching

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Computational Visual Media 2024年第3期10卷 487-503页

作者： yi-Xiao Li Guan Luo yi-Ke Xu Yu He Fang-Lue Zhang Song-Hai Zhang Department of Computer Science and Technology Tsinghua UniversityBeijingChinaand Beijing National Research Center for Information Science and Technology(BNRist)Tsinghua UniversityBeijingChina Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijingChina Victoria University of Wellington WellingtonNew Zealand

360°videos enable viewers to watch freely from different directions but inevitably prevent them from perceiving all the helpful *** mitigate this problem,picture-in-picture(PIP)guidance was proposed using preview windows to show regions of interest(ROIs)outside the current view *** identify several drawbacks of this representation and propose a new method for 360° film watching called *** enhances traditional PIP by adaptively arranging preview windows with changeable view ranges and *** addition,AdaPIP incorporates the advantage of arrow-based guidance by presenting circular windows with arrows attached to them to help users locate the corresponding ROIs more *** also adapted AdaPIP and Outside-In to HMD-based immersive virtual reality environments to demonstrate the usability of PIP-guided approaches beyond 2D *** user experiments on 2D screens,as well as in VR environments,indicate that AdaPIP is superior to alternative methods in terms of visual experiences while maintaining a comparable degree of immersion.

关键词： 360°videos picture-in-picture(PIP) virtual reality(VR) visual guidance

Heterogeneous engineering of MnSe@NC@ReS_(2) core-shell nanowires for advanced sodium-/potassium-ion batteries

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Rare Metals 2024年第8期43卷 3713-3723页

作者： Sheng-Jun Lu Jin-yi Lin Cai-Hong Wang Yu-Fei Zhang yi Zhang Hao-Sen Fan College of Materials Science and Metallurgy Engineering Guizhou University Guiyang 550025China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) have been attracting great attentions and widely been exploited due to the abundant sodium/potassium ***,the preparation of high-powered anode materials for SIBs/PIBs plays a decisive role for the commercial applications of SIBs/PIBs in the *** selenides are a class of potential anode materials for SIBs/PIBs because of their small band gap and high electrical *** this work,MnSe and ReS_(2) core-shell nanowires connecting by polydopamine derived carbon nanotube(MnSe@NC@ReS_(2)) have been successfully synthesized from growing ReS_(2) nanosheets array on the surface of MnSe@NC nano wires,which present excellent Na^(+)/K^(+) storage *** applied as SIBs anode,the specific capacity of 300 mAh·g^(-1) was maintwined after 400 cycles at the current density of 1.0 A·g^(-1).Besides,it could also keep 120 mAh·g^(-1) specific capacity after 900 cycles at 1.0 A·g^(-1) for the anode of *** heterogeneous engineering and one-dimensional-two-dimensional(1D-2D) hybrid strategies could provide an ideal strategy for the synthesis of new hetero-structured anode materials with outstanding battery performance for SIBs and PIBs.

关键词： Heterogeneous engineering Core-shell nanowires MnSe@NC@ReS_(2)nanowires Na^(+)batteries K^(+)batteries

Improved multi-scale inverse bottleneck residual network based on triplet parallel attention for apple leaf disease identification

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Journal of Integrative Agriculture 2024年第3期23卷 901-922页

作者： Lei Tang Jizheng yi Xiaoyao Li College of Computer&Information Engineering Central South University of Forestry and TechnologyChangsha 410004China Yuelushan Laboratory Carbon Sinks Forests Variety Innovation Center Changsha 410000China

Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from image texture and structural information. The difficulties in disease feature extraction in complex backgrounds slow the related research progress. To address the problems, this paper proposes an improved multi-scale inverse bottleneck residual network model based on a triplet parallel attention mechanism, which is built upon ResNet-50, while improving and combining the inception module and ResNext inverse bottleneck blocks, to recognize seven types of apple leaf(including six diseases of alternaria leaf spot, brown spot, grey spot, mosaic, rust, scab, and one healthy). First, the 3×3 convolutions in some of the residual modules are replaced by multi-scale residual convolutions, the convolution kernels of different sizes contained in each branch of the multi-scale convolution are applied to extract feature maps of different sizes, and the outputs of these branches are multi-scale fused by summing to enrich the output features of the images. Second, the global layer-wise dynamic coordinated inverse bottleneck structure is used to reduce the network feature loss. The inverse bottleneck structure makes the image information less lossy when transforming from different dimensional feature spaces. The fusion of multi-scale and layer-wise dynamic coordinated inverse bottlenecks makes the model effectively balances computational efficiency and feature representation capability, and more robust with a combination of horizontal and vertical features in the fine identification of apple leaf diseases. Finally, after each improved module, a triplet parallel attention module is integrated with cross-dimensional interactions among channels through rotations and residual transformations, which improves the parallel search efficiency of important features and the recogniti

关键词： multi-scale module inverse bottleneck structure triplet parallel attention apple leaf disease

Neddylation Regulation of Immune Responses

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Research 2024年第3期2023卷 545-559页

作者： Hongmei Mao Xin Lin yi Sun Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)of the Second Affiliated Hospital and Institute of Translational MedicineZhejiang University School of MedicineHangzhou 310029China Institute for Immunology School of MedicineTsinghua UniversityBeijing 100084China Changping Laboratory Beijing 102206China Cancer Center of Zhejiang University Hangzhou 310029China Zhejiang Provincial Clinical Research Center for Cancer HangzhouZhejiang ProvinceChina Key Laboratory of Molecular Biology in Medical Sciences HangzhouZhejiang ProvinceChina Research Center for Life Science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China.

Neddylation plays a vital role in post-translational modification, intricately shaping the regulation of diverse biological processes, including those related to cellular immune responses. In fact, neddylation exerts control over both innate and adaptive immune systems via various mechanisms. Specifically, neddylation influences the function and survival of innate immune cells, activation of pattern recognition receptors and GMP-AMP synthase–stimulator of interferon genes pathways, as well as the release of various cytokines in innate immune reactions. Moreover, neddylation also governs the function and survival of antigen-presenting cells, which are crucial for initiating adaptive immune reactions. In addition, neddylation regulates T cell activation, proliferation, differentiation, survival, and their effector functions, thereby ensuring an appropriate adaptive immune response. In this review, we summarize the most recent findings in these aspects and delve into the connection between dysregulated neddylation events and immunological disorders, especially inflammatory diseases. Lastly, we propose future directions and potential treatments for these diseases by targeting neddylation.

关键词： activation thereby initiating

Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： Xiao-Hong yi Chong-Chen Wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

Ore Geology,H-O-C Isotopes and 40Ar-39Ar Dating of the Wutonggou Iron Deposit,Eastern Tianshan,NW China:Implications for the Source,Timing,and Genesis of Hydrothermal Mineralization in a Sedimentary Iron Deposit

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Journal of Earth Science 2024年第4期35卷 1170-1185页

作者： Chun-Long Wang yi-Tian Wang State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourcesChina University of GeosciencesWuhan430074China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing100037China

The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern Tianshan,NW China,and has been regarded as a sedimentary iron *** hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits,previous studies mainly focused on sedimentary-related iron mineralization,while the nature and contribution of hydrothermal fluids are poorly ***,an integrated study of ore geology,H-O-C isotopes and^(40)Ar-^(39)Ar dating,is conducted on the Wutonggou deposit,in order to reveal the features,source,and timing of hydrothermal *** studied deposit includes two mining sections namely the Jianshan and ***δ^(18)O values of early magnetite from the Jianshan section range from+3.0‰to+5.8‰that nearly consistent with classic magmatic magnetite,while increase to 6.3‰-8.0‰in the late *** from the two sections shows comparable H-O isotopic compositions and identical fractionation trends,and is plotted in or periphery to the primary magmatic water *** from the two sections are broadly similar in carbon and oxygen isotopic compositions,and siderite from the Wutonggou section is plotted in the same ***,comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining ***,water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections,and caused the isotopic fractionation in late *** extracted from a hydrothermal siderite ore yielded a^(40)Ar-^(39)Ar plateau age of 299.5±2.0 Ma,indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity *** together,the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores,a

关键词： iron deposits H-O-C isotopes 40Ar-39Ar dating sedimentary iron deposits Wutonggou iron deposit eastern Tianshan