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Subspace Clustering via Block-Diagonal Decomposition

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Chinese Journal of Electronics 2024年

作者： Zhiqiang FU Yao ZHAO Dongxia CHANG yiming wang Institute of Information Science Beijing Jiaotong University Beijing Key Laboratory of Advanced Information Science and Network Technology China Construction Bank

The subspace clustering has been addressed by learning the block-diagonal self-expressive matrix. This block-diagonal structure heavily affects the accuracy of clustering but is rather challenging to obtain. A novel and effective subspace clustering model, i.e., subspace clustering via block-diagonal decomposition(SCBD), that can simultaneously capture the block-diagonal structure and gain the clustering result is proposed. In our model, a strict blockdiagonal decomposition is introduced to directly pursue the k block-diagonal structure corresponding to k clusters. In this novel decomposition, the self-expressive matrix is decomposed into the block indicator matrix to demonstrate the cluster each sample belongs to. Based on the strict block-diagonal decomposition, the block-diagonal shift is proposed to capture the local intra-cluster structure, which shifts the samples in the same cluster to get smaller distances and results in more discriminative features for clustering. Extensive experimental results on synthetic and real databases demonstrate the superiority of SCBD over other state-of-the-art methods.

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Annual nonmethane hydrocarbon trends in Beijing from 2000 to 2019

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Journal of Environmental Sciences 2022年第2期34卷 210-217页

作者： Dan Yao Guiqian Tang Jie Sun Yinghong wang Yuan Yang yiming wang Baoxian Liu Hong He Yuesi wang Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Airborne Particulate Matter Monitoring Technology Beijing Municipal Environmental Monitoring CenterBeijing 100048China Uniuersity of Chinese Academy of Sciences Beijing 100049China

High loads of ground-level ozone have occurred with the implementation of the Air Pollution Prevention and Control Action Plan.However,the long temporal variation in precursor nonmethane hydrocarbons(NMHCs)has rarely been studied.In this study,we examined the evolution of NMHCs in Beijing based on ambient measurements from 2000 to 2019.The results indicated that the annual variation of ambient NMHCs during 2000 and 2019 could be divided into two stages.The mixing ratios of NMHCs rapidly rose during 2000 and 2009(1.76 ppbv/year)but exhibited a downward trend from 2009 to 2019 at rate of 0.80 ppbv/yr.Moreover,the notable decrease in alkenes and aromatics after 2009 led to a sharp decrease in the propylene-equivalent concentration(PEC)(-0.80 ppbv/year).Implementation of emission reduction measures in Beijing have effectively reduced the contribution of vehicle-related sources,but the contribution of solvent usage and fuel consumption increased,which will become the focus of VOC control in Beijing in the future.

关键词： Beijing NMHCs Reactivity Temporal variation

A cation-dipole-reinforced elastic polymer electrolyte enabling long-cycling quasi-solid-state lithium metal batteries

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Journal of Energy Chemistry 2022年第12期75卷 340-348,I0009页

作者： Zhuyi wang yiming wang Pan Zhai Preeyaporn Poldorn Siriporn Jungsuttiwong Shuai Yuan Research Centre of Nanoscience and Nanotechnology Shanghai UniversityShanghai 200444China Center for Organic Electronic and Alternative Energy Department of Chemistry and Center of Excellence for Innovation in ChemistryFaculty of ScienceUbon Ratchathani UniversityUbon Ratchathani 34190Thailand

The application of ionic liquids(IL)in polymer electrolytes represents a safer alternative to the currently used organic solvents in lithium batteries due to their nonflammability and thermal stability.However,as a plasticizer,it is generally agreed that the introduction of ionic liquid usually leads to a trade-off between ion transport and mechanical properties of polymer electrolyte.Here we report the synthesis of an IL-embedded polymer electrolyte with both high ionic conductivity(2.77×10^(-4)S cm^(-1)at room temperature)and excellent mechanical properties(high tensile strength up to 11.4 MPa and excellent stretchability of 387%elongation at break)achieved by strong ion–dipole interactions between polymer electrolyte components,which was unveiled by the DFT calculation.Moreover,this polymer electrolyte also exhibits nonflammability,good thermal stability and the ability to recover reversibly from applied stress,i.e.,excellent elasticity.This highly viscoelastic polymer electrolyte enables tight interfacial contact and good adaptability with electrodes for stable lithium stripping/plating for 2000 h under a current density of 0.1 mA cm^(-2).By coupling with this polymer electrolyte,the LiFePO_(4)/Li cells exhibit outstanding cycling stability at room temperature as well as the reliability under extreme environmental temperature or being abused.

关键词： Elastic polymer electrolyte Ion-dipole interactions High tensile strength Quasi-solid-state lithium battery Long cycling

High-performance photodetector based on an interface engineering-assisted graphene/silicon Schottky junction

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Microsystems & Nanoengineering 2022年第1期8卷 73-81页

作者： Peirui Ji Shuming Yang Yu wang Kaili Li yiming wang Hao Suo Yonas Tesfaye Woldu Xiaomin wang Fei wang Liangliang Zhang Zhuangde Jiang State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Xi’an Jiaotong UniversityXi’an 710049China

Graphene/silicon Schottky junctions have been proven efficient for photodetection,but the existing high dark current seriously restricts applications such as weak signal detection.In this paper,a thin layer of gadolinium iron garnet(Gd3Fe5O12,GdIG)film is introduced to engineer the interface of a graphene/silicon Schottky photodetector.The novel structure shows a significant decrease in dark current by 54 times at a-2 V bias.It also exhibits high performance in a self-powered mode in terms of an Ilight/Idark ratio up to 8.2×10^(6)and a specific detectivity of 1.35×10^(13)Jones at 633 nm,showing appealing potential for weak-light detection.Practical suitability characterizations reveal a broadband absorption covering ultraviolet to near-infrared light and a large linear response with a wide range of light intensities.The device holds an operation speed of 0.15 ms,a stable response for 500 continuous working cycles,and long-term environmental stability after several months.Theoretical analysis shows that the interlayer increases the barrier height and passivates the contact surface so that the dark current is suppressed.This work demonstrates the good capacity of GdIG thin films as interlayer materials and provides a new solution for high-performance photodetectors.

关键词： Schottky performance interface

Revision rhinoplasty for contracted nose:A systematic review and meta-analysis

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Chinese Journal Of Plastic and Reconstructive Surgery 2023年第2期5卷 100-108页

作者： yiming wang Guanhuier wang Yonghuan Zhen Yang An Department of Plastic Surgery Peking University Third HospitalBeijing 100191China

Background:This study aimed to review treatments and evaluate the aesthetic outcomes,complications,and reoperation rates regarding surgical correction for a postoperative contracted nose.Methods:PubMed,MEDLINE,and Embase databases were searched for studies detailing aesthetic outcomes and complications of surgical correction of a contracted nose.Surgical procedures,adjuvant treatment,outcomes,and complications were synthesized and analyzed.Results:Nine articles encompassing 376 patients were included in the systematic review,and six articles(198 participants)were included in the meta-analysis.The most frequently used graft material was the autologous rib cartilage(61.1%).Surgical procedures were heterogeneous in these studies.The nasolabial angle reduced by 9.52°(95%confidence interval(CI):(-11.95,-7.09),P<0.0001),and the nasal length increased significantly(standardized mean difference(SMD)=2.25,95%CI:(1.26,2.23),P<0.00001).However,the evidence was insufficient to determine a significant change in the columellar-labial angle(SMD=-0.95,95%CI:(-2.19,0.29),P=0.13)and columellar-lobular angle(SMD=2.39,95%CI:(-1.20,5.97),P=0.19).Aesthetic dissatisfaction(12.5%)and infection(4.5%)were the most commonly reported complications.Reoperation was performed in 5.3%of patients.Conclusion:Surgical correction can increase the nasal length,reduce the nasolabial angle,and have a low reoperation rate.No significant improvement in the columellar-labial or columellar-lobular angle was observed.

关键词： Nasal deformity Contracted nose Rhinoplasty Postoperative complication Meta-analysis Systematic review

Pressure-driven symmetry breaking and electron disproportionation of the trigonal Nb_(3)cluster in Nb_(3)Cl_(8)

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 153-158页

作者： Zimin Jiang Dequan Jiang yiming wang Chen Li Ke Liu Ting Wen Fuyang Liu Zhengyang Zhou Yonggang wang Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100094China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201899China

Symmetry breaking of metal cluster-based strongly correlated systems can give rise to collective phenomena.Here,the twodimensional Nb_(3) cluster compound Nb_(3)Cl_(8) is shown to suffer dramatic symmetry breaking and electron disproportionation under compression.A structural phase transition from trigonal P–3m1 to monoclinic C2/m is observed near 8 GPa with the three-fold symmetry breaking.Electron disproportionation occurs on Nb_(3) clusters from delocalized Nb^(8/3+)Nb^(8/3+)Nb^(8/3+)to localized Nb^(3+)Nb^(3+)Nb^(2+),which results in a subtle bandgap discontinuity,as evidenced by electrical transport and UV-Vis absorption measurements.

关键词： Nb_(3)Cl_(8) symmetry breaking electron disproportionation layered semiconductor high pressure

A robust reporting system for measurement of SARS-CoV-2 spike fusion efficiency

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Signal Transduction and Targeted Therapy 2022年第7期7卷 2141-2143页

作者： Cong Huang Yang Yang Peng Yang Fei wang Xinyu Li Xiang Song yiming wang Cuiyun Yu Xuejun wang Shengqi wang Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study University of South China421001 HengyangChina State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology100850 BeijingChina Department of Pharmaceutics Shenyang Pharmaceutical University110016 ShenyangChina

Dear Editor,During the COVID-19 pandemic,several SARS-CoV-2 variants such as Alpha,Delta,and Omicron successively became dominant worldwide.The infection of SARS-CoV-2 is triggered by the binding of spike protein to the cell-surface receptor angiotensinconverting enzyme 2(ACE2),which then fuses with cell membrane or lysosomal membrane after endocytosis.1 Extensive cell fusion and syncytia formation are a signature feature of severe SARS-CoV-2 and may play an important role in COVID-19 pathogenesis.Research has shown that SARS-CoV-2 spikemediated cell fusion leads to the formation of abnormal and multinucleated cells in the lungs of patients.2 Accordingly,the fusion ability of SARS-CoV-2 spike protein may be a leading indicator of viral infectivity and disease severity in SARS-CoV-2 patients.

关键词： ACE2 pathogenesis severity

Suppression of ETI by PTI priming to balance plant growth and defense through an MPK3/MPK6-WRKYs-PP2Cs module

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Molecular Plant 2023年第5期16卷 903-918页

作者： Dacheng wang Lirong Wei Ting Liu Jinbiao Ma Keyi Huang Huimin Guo Yufen Huang Lei Zhang Jing Zhao Kenichi Tsuda yiming wang Key Laboratory of Biological Interactions and Crop Health Department of Plant PathologyNanjing Agricultural UniversityNanjing 210095China Key Laboratory of Integrated Management of Crop Disease and Pests Ministry of EducationNanjing Agricultural UniversityNanjingChina State Key Laboratory of Agricultural Microbiology Hubei Hongshan LaboratoryHubei Key Lab of Plant PathologyCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina

Pattern-triggered immunity(PTI)and effector-triggered immunity(ETI)are required for host defense against pathogens.Although PTI and ETI are intimately connected,the underlying molecular mechanisms remain elusive.In this study,we demonstrate that flg22 priming attenuates Pseudomonas syringae pv.tomato DC3000(Pst)AvrRpt2-induced hypersensitive cell death,resistance,and biomass reduction in Arabidopsis.Mitogen-activated protein kinases(MAPKs)are key signaling regulators of PTI and ETI.The absence of MPK3 and MPK6 significantly reduces pre-PTI-mediated ETI suppression(PES).We found that MPK3/MPK6 interact with and phosphorylate the downstream transcription factor WRKY18,which regulates the expression of AP2C1 and PP2C5,two genes encoding protein phosphatases.Furthermore,we observed that the PTI-suppressed ETI-triggered cell death,MAPK activation,and growth retardation are significantly attenuated in wrky18/40/60 and ap2c1 pp2c5 mutants.Taken together,our results suggest that the MPK3/MPK6-WRKYs-PP2Cs module underlies PES and is essential for the maintenance of plant fitness during ETI.

关键词： PAMP-triggered immunity effector-triggered immunity MAPK,WRKY18 protein phosphatase

Molecular mechanism of fly ash affecting the performance of cemented backfill material

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International Journal of Minerals,Metallurgy and Materials 2023年第8期30卷 1560-1572页

作者： Shuo Yang Jiangyu Wu Hongwen Jing Xinguo Zhang Weiqiang Chen yiming wang Qian Yin Dan Ma State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Shandong Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Research Institute of Building Science Co.Ltd.Nanjing 210008China Department of Materials University of OxfordParks RdOxfordOX13PHUnited Kingdom Department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterManchester M139PLUnited Kingdom School of Mines China University of Mining and TechnologyXuzhou 221116China

The great challenge of cemented tailings backfill(CTB)is difficult simultaneously maintaining its excellent mechanical properties and low cost.Fly ash(FA)can potentially address this problem and further replace cement in favor of low carbon development.However,its mechanism on CTB with low cement dosage and low Ca system remains unclear.Consequently,this study conducted uniaxial compression,Xray diffraction(XRD),and scanning electron microscopy(SEM)-energy dispersive spectrometer(EDS)tests to investigate the effect of FA dosage on the mechanical property and microstructure of CTB.A molecular model of FA-CSH was constructed to reproduce the molecular structure evolution of CTB with FA based on the test results.The influences of FA dosage and calcium/silica molar ratio(Ca/Si ratio)on the matrix strength and failure model were analyzed to reveal the mechanism of FA on calcium silicate hydrated(C-S-H).The results show that the strength of CTB increases initially and then decreases with FA dosage,and the FA supplement leads to a decrease in Ca(OH)_(2) diffraction intensity and Ca/Si ratio around the FA particles.XRD and SEM-EDS findings show that the Ca/Si ratio of C-S-H decreases with the progression of hydration.The FA-CSH model indicates that FA can reinforce the silica chain of C-S-H to increase the matrix strength.However,this enhancement is weakened by supplementing excessive FA dosage.In addition,the hydrogen bonds among water molecules deteriorate,reducing the matrix strength.A low Ca/Si ratio results in an increase in water molecules and a decrease in the ionic bonds combined with Ca^(2+).The hydrogen bonds among water molecules cannot withstand high stresses,resulting in a reduction in strength.The water absorption of the FA-CSH model is negatively correlated with the FA dosage and Ca/Si ratio.The use of optimal FA dosage and Ca/Si ratio leads to suitable water absorption,which further affects the failure mode of FA-CSH.

关键词： fly ash cemented tailings backfill calcium/silica ratio microstructure molecular dynamics simulation