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Experiencing winter for spring flowering: A molecular epigenetic perspective on vernalization

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Journal of Integrative Plant Biology 2020年第1期62卷 104-117页

作者： xiao luo Yuehui He National Key Laboratory of Plant Molecular Genetics & Shanghai Center for Plant Stress Biology Center for Excellence in Molecular Plant Sciences The Chinese Academy of Sciences

Many over-wintering plants, through vernalization, overcome a block to flowering and thus acquire competence to flower in the following spring after experiencing prolonged cold exposure or winter cold. The vernalization pathways in different angiosperm lineages appear to have convergently evolved to adapt to temperate climates. Molecular and epigenetic mechanisms for vernalization regulation have been well studied in the crucifer model plant Arabidopsis ***, we review recent progresses on the vernalization pathway in Arabidopsis. In addition, we summarize current molecular and genetic understandings of vernalization regulation in temperate grasses including wheat and Brachypodium, two monocots from Pooideae, followed by a brief discussion on divergence of the vernalization pathways between Brassicaceae and Pooideae.

关键词： winter spring temperate

Existence and multiplicity of normalized solutions for a class of fractional Choquard equations

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Science China Mathematics 2020年第3期63卷 539-558页

作者： Gongbao Li xiao luo Hubei Key Laboratory of Mathematical Sciences and School of Mathematics and Statistics Central China Normal University

In this paper, we study the existence and multiplicity of solutions with a prescribed L2-norm for a class of nonlinear fractional Choquard equations in RN:(-△)su-λu =(κα*|u|p)|u|p-2u,where N≥3,s∈(0,1),α∈(0,N),p∈(max{1 +(α+2s)/N,2},(N+α)/(N-2s)) and κα(x)=|x|α-N. To get such solutions,we look for critical points of the energy functional I(u) =1/2∫RN|(-△)s/2u|2-1/(2p)∫RN(κα*|u|p)|u|p on the constraints S(c)={u∈Hs(RN):‖u‖L2(RN)2=c},c >*** the value p∈(max{1+(α+2s)/N,2},(N+α)/(N-2s)) considered, the functional I is unbounded from below on S(c). By using the constrained minimization method on a suitable submanifold of S(c), we prove that for any c>0, I has a critical point on S(c) with the least energy among all critical points of I restricted on S(c). After that,we describe a limiting behavior of the constrained critical point as c vanishes and tends to infinity. Moreover,by using a minimax procedure, we prove that for any c>0, there are infinitely many radial critical points of I restricted on S(c).

关键词： fractional Choquard normalized solution limiting behavior constrained minimization

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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A positive solution of a nonlinear Schrdinger system with nonconstant potentials

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Science China Mathematics 2017年第12期60卷 2407-2420页

作者： HE QiHan luo xiao College of Mathematics and Information Science Guangxi University School of Mathematics and Statistics Central China Normal University

In this paper, we study the existence of positive solutions to the following Schr¨odinger system:{-?u + V_1(x)u = μ_1(x)u^3+ β(x)v^2u, x ∈R^N,-?v + V_2(x)v = μ_2(x)v^3+ β(x)u^2v, x ∈R^N,u, v ∈H^1(R^N),where N = 1, 2, 3; V_1(x) and V_2(x) are positive and continuous, but may not be well-shaped; and μ_1(x), μ_2(x)and β(x) are continuous, but may not be positive or anti-well-shaped. We prove that the system has a positive solution when the coefficients Vi(x), μ_i(x)(i = 1, 2) and β(x) satisfy some additional conditions.

关键词： Schrdinger system nonconstant potentials variational methods

Normalized solutions for a fourth-order Schrődinger equation with a positive second-order dispersion coefficient

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Science China Mathematics 2023年第6期66卷 1237-1262页

作者： xiao luo Tao Yang School of Mathematics Hefei University of TechnologyHefei 230009China Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

In this paper,we study normalized solutions to a fourth-order Schrődinger equation with a positive second-order dispersion coefficient in the mass supercritical *** the well-studied case where the second-order term is zero or negative,the geometrical structure of the corresponding energy functional changes dramatically and this makes the solution set *** suitable control of the second-order dispersion coefficient and mass,we find at least two radial normalized solutions,a ground state and an excited state,together with some asymptotic *** is worth pointing out that in the considered repulsive case,the compactness analysis of the related Palais-Smale sequences becomes more *** forces the implementation of refined estimates of the Lagrange multiplier and the energy level to obtain normalized solutions.

关键词： fourth-order Schrodinger equation mixed dispersion normalized solution variational method

Recent progresses on the development of thioxo-naphthalimides

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Chinese Chemical Letters 2020年第11期31卷 2877-2883页

作者： xiao luo Youjun Yang Xuhong Qian School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China State Key Laboratory of Bioreactor Engineering School of PharmacyEast China University of Science and TechnologyShanghai 200237China

Thioxo/dithioxo-naphthalimide is a class of rarely visited fluorophore,first synthesized in *** chemistry was devised to achieve mono or dual thionation of the two carbonyl groups of 1,*** effectively shifts absorption maximum to longer spectral wavelength,significantly increase absorption coefficients,and dramatically enhances intersystem crossing efficiency with respect to their *** were first explored as potent photocleavers to induce DNA strand break and novel photosensitizers for photodynamic *** recent years,the unique chemistry of thioxo groups has been harnessed to achieve new applications,such as fluorescent sensors for heave metal *** unique photochemical and photophysical characteristics revitalize them intriguing functional molecules to *** this short review,we wish to revisit their first discovery,facile synthesis,and the endeavors on the use of thioxo/dithioxo-naphthalimides for novel chemical and biomedical applications.

关键词： Thioxo-naphthalimide Intersystem crossing Photocleaver Photosensitizer Fluorescent sensor

High throughput bandwidth optimized VLSI design for motion compensation in AVS HDTV decoder

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第6期9卷 822-832页

作者： Kai luo Dong-xiao LI Ming ZHANG Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

In this paper we present a motion compensation (MC) design for the newest Audio Video coding Standard (AVS) of China. Because of compression-efficient techniques of variable block size (VBS) and sub-pixel interpolation, intensive pixel calculation and huge memory access are required. We propose a parallel serial filtering mixed luma interpolation data flow and a three-stage multiplication free chroma interpolation scheme. Compared to the conventional designs, the integrated architecture supports about 2.7 times filtering throughput. The proposed MC design utilizes Vertical Z processing order for reference data re-use and saves up to 30% memory bandwidth. The whole design requires 44.3k gates when synthesized at 108 MHz clock frequency using 0.18-μm CMOS technology and can support up to 1920×1088@30 fps AVS HDTV video decoding.

关键词： Audio Video coding Standard (AVS) Motion compensation (MC) Interpolation VLSI Architecture

Quantum Teleportation between Two Distant Bose-Einstein Condensates

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Chinese Physics Letters 2012年第6期29卷 24-27页

作者： GUO Yu luo xiao-Bing Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physics and Electronic Science Changsha University of Science and TechnologyChangsha 410114 Department of Physics Jinggangshan UniversityJi’an 343009

We propose protocols for quantum teleportation of superposed coherent states of atomic Bose-Einstein *** use the photon entanglement states as the quantum channel,which makes it possible to realize the distant teleportation of atomic *** robust protocols are introduced:one is a single-photon scheme in which an entangled single-photon state serves as the quantum channel,and the other is a multi-photon scheme where an entangled coherent state of the probe lasers is used as the quantum channel.

关键词： quantum Einstein coherent

Synthesis of Bio-Plasticizer from Soybean Oil and Its Application in Poly(Vinyl Chloride) Films

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Journal of Renewable Materials 2020年第10期8卷 1295-1304页

作者： xiao luo Hongying Chu Mengqi Liu Henan University of Chinese Medicine Zhengzhou450046China Yellow River Conservancy Technical Institute Kaifeng475004China

Herein,epoxidized soybean oil methyl ester(ESOM)plasticizer was synthesized for the preparation of plasticized poly(vinyl chloride)(PVC)films by the alcoholysis and *** chemical structure of ESOM was investigated by infrared spectrum and 1 H nuclear magnetic *** effect of content of ESOM and petroleum based plasticizer di-2-ethylhexyl phthalate(DEHP)on the performance of plasticized PVC films was *** result showed that substituting DEHP with ESOM can improve the thermal stability of plasticized PVC *** the weight ratio of ESOM and PVC is fixed at 1:2,plasticized PVC film presents higher elongation at break(350.8%vs.345.1%)and lower tensile strength(14.21 MPa vs.15.8 MPa)compared with PVC plasticized with *** showed less weight loss than DEHP in all *** excellent migration resistance of ESOM is helpful to improve stability of plasticized PVC *** all,the obtained bio-based plasticizer will be potential to replace petroleum based plasticizer DEHP in flexible PVC materials.

关键词： Soybean oil epoxy plasticizer poly(vinyl chloride) glass transition temperature