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GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang qin xiao LUO Hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

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Understanding the pathogenic evolution of Zika virus

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Science China(Life Sciences) 2016年第7期59卷 737-739页

作者： xiao-Feng qin Center of Systems Medicine Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100005 China Suzhou Institute of Systems Medicine Suzhou 215123 China

Unlike the previous circulating strains that were not associ- ated with significant human pathology, recent circulating Zika virus （ZIKV） strains isolated during the 2015-2016 Brazilian Outbreak are highly suspected to cause neuropa- thology, including disorders of fetal brain development and Guillain-Barr6 syndrome （Broutet et al., 2016）. Studies have revealed that recent ZIKV strains can be spread through maternal-fetal （Calvet et al., 2016） and sexual （Hills et al., 2016） transmission, in addition to the traditional route of infection via mosquitoes.

关键词：病毒演变病原大脑发育病理学流行株综合征菌株

Pre-compensation of Friction for CNC Machine Tools through Constructing a Nonlinear Model Predictive Scheme

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 62-76页

作者： Qunbao xiao Min Wan Xuebin qin State IJR Center of Aerospace Design and Additive Manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Nonlinear friction is a dominant factor afecting the control accuracy of CNC machine *** paper proposes a friction pre-compensation method for CNC machine tools through constructing a nonlinear model predictive *** nonlinear friction-induced tracking error is frstly modeled and then utilized to establish the nonlinear model predictive scheme,which is subsequently used to optimize the compensation signal by treating the friction-induced tracking error as the optimization *** the optimization procedure,the derivative of compensation signal is constrained to avoid vibration of machine *** contrast to other existing approaches,the proposed method only needs the parameters of Stribeck friction model and an additional tuning parameter,while fnely identifying the parameters related to the pre-sliding phenomenon is not *** a result,it greatly facilitates the practical *** air cutting and real cutting experiments conducted on an in-house developed open-architecture CNC machine tool prove that the proposed method can reduce the tracking errors by more than 56%,and reduce the contour errors by more than 50%.

关键词： Nonlinear model predictive control Friction compensation P-PI controller Stribeck model

Local weak solutions of the isentropic compressible Navier-Stokes equations in a half-space

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Science China Mathematics 2022年第5期65卷 993-1002页

作者： qin Duan Xiangdi huang College of Mathematics and Statistics Shenzhen UniversityShenzhen 518060China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Hua Loo-Keng Center for Mathematical Sciences Chinese Academy of SciencesBeijing 100190China

In this paper, we establish the local existence of weak solutions with higher regularity of the threedimensional half-space compressible isentropic Navier-Stokes equations with the adiabatic exponent γ > 1 in the pre... 详细信息

关键词： Navier-Stokes equation half-space local weak solution vacuum

A NUMERICAL STUDY OF INDENTATION WITH SMALL SPHERICAL INDENTERS

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Acta Mechanica Solida Sinica 2009年第1期22卷 18-26页

作者： Jiang qin Shaoxing Qu Xue Feng Yonggang huang Jianliang xiao Keh-Chih Hwang Department of Engineering Mechanics Tsinghua University Beijing 100084 China Department of Mechanics Zhejiang University Hangzhou 310027 China Department of Civil and Environmental Engineering Northwestern University Evanston IL 60208 USA Department of Mechanical Engineering Northwestern University Evanston IL 60208 USA

The finite element method for the conventional theory of mechanism-based strain gradient plasticity is used to study the indentation size effect. For small indenters （e.g., radii on the order of 10μm）, the maximum allowable geometrically necessary dislocation （GND） density is introduced to cap the GND density such that the latter does not become unrealistically high. The numerical results agree well with the indentation hardness data of iridium. The GND density is much larger than the density of statistically stored dislocations （SSD） underneath the indenter, but this trend reverses away from the indenter. As the indentation depth （or equivalently, contact radius） increases, the GND density decreases but the SSD density increases.

关键词： indentation size effect spherical indenters geometrically necessary dislocations,maximum density

Facile preparation of covalent organic frameworks@alginate composite beads for enhanced uranium(Ⅵ) adsorption

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Rare Metals 2022年第4期41卷 1323-1331页

作者： Pan Duan Duo-Yu Lin Wei-Ting Yang xiao-Jing huang A-Hui Sun qin-He Pan Key Laboratory of Advanced Materials of Tropical Island Resources Ministry of EducationChemical Engineering and TechnologyHainan UniversityHaikou 570228China

Covalent organic frameworks(COFs) have broad application prospects in adsorption and ***,as COFs are generally in powder form,their superior performance at the laboratory scale is difficult to transfer into pilot-or industrial-scale ***,there is a strong and urgent need to structure COFs into monolithic ***,a facile strategy was developed to prepare COFs@alginate composite *** composite beads comprising different COFs including TpPa-1(2,4,6-triformylphloroglucinol(Tp) and p-phenylenediamine(Pa-1)as monomers),TpDb(Tp and 2,5-diaminobenzonitrile(Db)as monomers) and TpTt(Tp and 1,3,5-triazine-2,4,6-triamine(Tt) as monomers) with controlled COF loading and product size have been facilely achieved via this strategy,validating the applicability of this ***,the representative TpDb@alginate composite beads showed good adsorption performance of uranium(VI) in aqueous solution with high adsorption capacity(635 mg·g^(-1)),good interference immunity and *** work offers a practical approach for incorporation of COFs into polymer matrix,which can serve as potential adsorbents for radioactive wastewater treatment.

关键词： Covalent organic frameworks Alginate Composite beads Uranium Adsorption

MicroRNA let-7a： a novel therapeutic candidate in prostate cancer

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Asian Journal of Andrology 2014年第2期16卷 327-328页

作者： xiao-qin Wu Cheng huang Xin-Hua Liu Jun Li School of Pharmacy Anhui Medical University institute for Liver Diseases of Anhui Medical University (AMU) Key Laboratory of Antiinflammatory and Immune Medicine (Anhui Medical University) Ministry of Education Hefei China.

Dear Editor, It is known that microRNA let-7a can be useful for diagnosis and therapy of cancer, including prostate cancer （PCa）.1 A recent article by Wang et al. 2 comprehensively showed that let-7al could inhibit the expression of insulin-like growth factor- 1 receptor （IGF 1 R） by directly targeting the T1 and T2 sites in the 3＇ untranslated region （3＇UTR） of IGF 1R mRNA. Furthermore, they found that let-7a 1-mediated IGF I R downregulation was accompanied by attenuation of Elk1 activity and c-fos expression, inhibition of PC-3 cell proliferation, cell cycle arrest and induced apoptosis and that inhibition oflet-7al could up-regulate IGF 1R accompanied by an increase of Elk1 activity and c-fos expression,

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Explicit structure-preserving geometric particle-in-cell algorithm in curvilinear orthogonal coordinate systems and its applications to whole-device 6D kinetic simulations of tokamak physics

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Plasma Science and Technology 2021年第5期23卷 18-41页

作者： Jianyuan xiao Hong qin School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026People's Republic of China Plasma Physics Laboratory Princeton UniversityPrincetonNJ 08543United States of America

Explicit structure-preserving geometric particle-in-cell(PIC)algorithm in curvilinear orthogonal coordinate systems is *** work reported represents a further development of the structure-preserving geometric PIC algorithm achieving the goal of practical applications in magnetic fusion *** algorithm is constructed by discretizing the field theory for the system of charged particles and electromagnetic field using Whitney forms,discrete exterior calculus,and explicit non-canonical symplectic *** addition to the truncated infinitely dimensional symplectic structure,the algorithm preserves exactly many important physical symmetries and conservation laws,such as local energy conservation,gauge symmetry and the corresponding local charge *** a result,the algorithm possesses the long-term accuracy and fidelity required for first-principles-based simulations of the multiscale tokamak *** algorithm has been implemented in the Sym PIC code,which is designed for highefficiency massively-parallel PIC simulations in modern *** code has been applied to carry out whole-device 6 D kinetic simulation studies of tokamak physics.A self-consistent kinetic steady state for fusion plasma in the tokamak geometry is numerically found with a predominately diagonal and anisotropic pressure *** state also admits a steady-state subsonic ion flow in the range of 10 km s-1,agreeing with experimental observations and analytical calculations Kinetic ballooning instability in the self-consistent kinetic steady state is *** is shown that high-n ballooning modes have larger growth rates than low-n global modes,and in the nonlinear phase the modes saturate approximately in 5 ion transit times at the 2%level by the E×B flow generated by the *** results are consistent with early and recent electromagnetic gyrokinetic simulations.

关键词： curvilinear orthogonal mesh charge-conservative particle-in-cell symplectic algorithm whole-device plasma simulation

Effects of different rotation patterns on the occurrence of clubroot disease and diversity of rhizosphere microbes

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Journal of Integrative Agriculture 2020年第9期19卷 2265-2273页

作者： YANG xiao-xiang huang xiao-qin WU Wen-xian XIANG Yun-jia DU Lei ZHANG Lei LIU Yong Institute of Plant Protection Sichuan Academy of Agricultural SciencesChengdu 610066P.R.China Key Laboratory of Integrated Pest Management on Crops in Southwest Ministry of Agriculture and Rural AffairsChengdu 610066P.R.China

Clubroot disease, caused by Plasmodiophora brassicae, is one of the most destructive soil-borne diseases in cruciferous crops worldwide. New strategies are urgently needed to control this disease, as no effective disease-resistant varieties or chemical control agents exist. Previously, we found that the incidence rate and disease index of clubroot in oilseed rape decreased by 50 and 40%, respectively, when oilseed rape was planted after soybean. In order to understand how different rotation patterns affect the occurrence of clubroot in oilseed rape, high-throughput sequencing was used to analyze the rhizosphere microbial community of oilseed rape planted after leguminous (soybean, clover), gramineous (rice, maize) and cruciferous (oilseed rape, Chinese cabbage) crops. Results showed that planting soybeans before oilseed rape significantly increased the population density of microbes that could inhibit P. brassicae (e.g., Sphingomonas, Bacillus, Streptomyces and Trichoderma). Conversely, consecutive cultivation of cruciferous crops significantly accumulated plant pathogens, including P. brassicae, Olpidium and Colletotrichum (P<0.05). These results will help to develop the most effective rotation pattern for reducing clubroot damage.

关键词： oilseed rape clubroot Gramineae Leguminosae Cruciferae rhizosphere soil