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Science China Chemistry 2024年

作者： Wen-Tao Dai ting-ting liu Qixia Bai Zhe Zhang Pingshan Wang wei Lu Qi Zhang Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry Sichuan University Institute of Environmental Research at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of Education Guangzhou University

The size complementarity between a host and a guest is a critical prerequisite for selective molecular recognition. Numerous artificial host systems have been designed to achieve size-selective recognition and chemical transformations. However, the inherent challenge lies in the fixed selectivity governed by a size-exclusion mechanism dictated by the host’s *** the selectivity necessitates structural modifications of hosts. Examples of host systems with modifiable sizeselectivity are rare. In this study, we present an approach to modulating guest-selectivity via endo-functionalization of supramolecular cavities. Heteroleptic Pd2A3B-cages are constructed with a Pd2A3precursor or directly from palladium ions and relevant ligands. Furthermore, the simultaneous and selective formation of multiple hetero-cages was achieved by simply mixing PdIIand the free ligands in a one-pot reaction. The fidelity of the assembly process relies on cooperative steric control at the periphery and within the cavity of the hetero-cages, respectively. The central steric group also functions as the endohedral moiety. Variations of the endohedral groups facilitate facile and modular derivatization of the microenvironment within the cages, enabling the fine-tuning of guest binding affinities as evidenced by titration experiments. This strategy offers a new solution for the development of customized host structures.

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Transient Monte Carlo simulation of phonon transport in silicon nanofilms with the local heat source

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Science China(Technological Sciences) 2024年第7期67卷 2087-2098页

作者： LI JiaQi CAI JiuQing LI Rui liu ZhiChun liu wei School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan 430074China Wuhan Second Ship Design and Research Institute Wuhan 430205China

Accurate prediction of junction temperature is crucial for the efficient thermal design of silicon nano-devices. In nano-scale semiconductor devices, significant ballistic effects occur due to the mean free path of phonons comparable to the heat source size and device scale. We employ a three-dimensional non-gray Monte Carlo simulation to investigate the transient heat conduction of silicon nanofilms with both single and multiple heat sources. The accuracy of the present method is first verified in the ballistic and diffusion limits. When a single local heat source is present, the width of the heat source has a significant impact on heat conduction in the domain. Notably, there is a substantial temperature jump at the boundary when the heat source width is 10 *** increasing heat source width, the boundary temperature jump weakens. Furthermore, we observe that the temperature excitation rate is independent of the heat source width, while the temperature influence range expands simultaneously with the increase in heat source width. Around 500 ps, the temperature and heat flux distribution in the domain stabilize. In the case of dual heat sources, the hot zone is broader than that of a single heat source, and the temperature of the hot spot decreases as the heat source spacing increases. However, the mean heat flux remains unaffected. Upon reaching a spacing of 200 nm between the heat sources, the peak temperature in the domain remains unchanged once a steady state is reached. These findings hold significant implications for the thermal design of silicon nano-devices with local heat sources.

关键词： phonon transport Monte Carlo simulation transient heat conduction silicon nanofilms local heat source

Comparative analysis of primate and pig cells reveals primate-specific PINK1 expression and phosphorylation

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Zoological Research 2024年第2期45卷 242-252页

作者： Xiu-Sheng Chen Rui Han Yan-ting liu wei Huang Qi Wang Xin Xiong Ying Zhang Jian-Guo Zhao Shi-Hua Li Xiao-Jiang Li wei-Li Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)GHM Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong 510632China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

PTEN-induced putative kinase 1(PINK1),a mitochondrial kinase that phosphorylates Parkin and other proteins,plays a crucial role in mitophagy and protection against *** in PINK1 and Parkin can lead to loss of function and early onset Parkinson's ***,there is a lack of strong in vivo evidence in rodent models to support the theory that loss of PINK1 affects mitophagy and induces ***,PINK1 knockout pigs(Sus scrofa)do not appear to exhibit *** our recent work involving non-human primates,we found that PINK1 is selectively expressed in primate brains,while absent in rodent *** extend this to other species,we used multiple antibodies to examine the expression of PINK1 in pig *** contrast to tissues from cynomolgus monkeys(Macaca fascicularis),our data did not convincingly demonstrate detectable PINK1expression in pig *** of PINK1 in cultured pig cells did not result in altered Parkin and BAD phosphorylation,as observed in cultured monkey cells.A comparison of monkey and pig striatum revealed more PINK1-phosphorylated substrates in the monkey ***,PINK1 knockout in pigs did not lead to obvious changes in the phosphorylation of Parkin and *** findings provide new evidence that PINK1expression is specific to primates,underscoring the importance of non-human primates in investigating PINK1function and pathology related to PINK1 deficiency.

关键词： PINK1 Parkin Mitochondria Phosphorylation Non-human primates Pigs

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

Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-Yang liu Jing-wei liu Gang Li Jing-Xiang Zhao College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025China

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and *** this work,by means of the density functional theory(DFT) calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM_(1-4)@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions(OER),oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER).The computed results reveal that the Pd_(2),Pd_(4) and Pt_(1) anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd_(1) and Pt_(2)@graphdiyne can exhibit excellent catalytic performance for water splitting(OER/HER) with the overpotentials of 0.55/0.17 and 0.43/0.03 *** addition,Ni_(1) and Pd_(3) anchored GDY can perform as bifunctional catalysts for metal-air cells(OER/ORR) and fuels cells(ORR/HER) with the overpotentials of 0.34/0.32 and 0.42/0.04 V,***,by precisely controlling the numbers of atoms in clusters,the TM_(1-4) anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism

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Advances in Atmospheric Sciences 2024年第5期41卷 959-973页

作者： Fangchi liu Xiaojing JIA wei DONG Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhouZhejiang 310058China

The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–*** current work investigates the possible mechanisms accounting for these distinct TPSC *** results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced *** circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern *** anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western ***,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern *** analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream *** warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the ***,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in ***,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP.

关键词： snow cover Tibetan Plateau long-term changes spring

Effect of Ti Particles on the Microstructure and Mechanical Properties of AZ91 Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 513-524页

作者： Lu Xiao ting-ting liu Yue Chu Bo Song Jie Zhao Xian-Hua Chen Kai-Hong Zheng Fu-Sheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing 400044China lntelligent Manufacturing and Automobile School Chongqing College of Electronic EngineeringChongqing 401331China School of Materials and Energy Southwest UniversityChongqing 400715China Science and Technology Research Institute of CNNC 404 Co.LTD Gansu 735100China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China

Spherical micro-Ti particle(TiP)-reinforced AZ91 magnesium alloy composites were fabricated by semi-solid stirring assisted ultrasonic vibration,which were then subjected to hot *** microstructure results showed that the addition of Ti particles refined the grain size and decreased the texture intensity of the as-extruded AZ91 *** Al3Ti phase with a thickness of 100 nm formed at the Ti/Mg interface,which had a non-coherent relationship with the magnesium *** as-extruded 1 vol.%TiP/AZ91 composite exhibited the best comprehensive mechanical properties,with yield strength,ultimate tensile strength,and elongation at break of 366 MPa,456 MPa,and 14.6%,respectively,which were significantly higher than those of the AZ91 ***,the addition of Ti particles can improve the strength and ductility of the AZ91 alloy,demonstrating the value of magnesium matrix composites for commercial applications.

关键词： Magnesium matrix composites Ti particles Interface Mechanical properties

Pickering emulsion transport in skeletal muscle tissue:A dissipative particle dynamics simulation approach

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Chinese Journal of Chemical Engineering 2024年第4期68卷 65-75页

作者： Xuwei liu wei Chen Yufei Xia Guanghui Ma Reiji Noda wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Division of Environmental Engineering Science Graduate School of Science and TechnologyGunma University1-5-1 Tenjin-choKiryuGunma 376-8515Japan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Lymph node targeting is a commonly used strategy for particulate vaccines,particularly for Pickering ***,extensive research on the internal delivery mechanisms of these emulsions,especially the complex intercellular interactions of deformable Pickering emulsions,has been surprisingly *** gap in knowledge holds significant potential for enhancing vaccine *** study aims to address this by summarizing the process of lymph-node-targeting transport and introducing a dissipative particle dynamics simulation method to evaluate the dynamic processes within cell *** transport of Pickering emulsions in skeletal muscle tissue is specifically investigated as a case *** factors impacting the transport process are explored,including local cellular tissue environmental factors and the properties of the Pickering emulsion *** simulation results primarily demonstrate that an increase in radial repulsive interaction between emulsion particles can decrease the transport ***,larger intercellular gaps also diminish the transport efficiency of emulsion droplet particles due to the increased motion complexity within the intricate transport space compared to a single *** study sheds light on the nuanced interplay between engineered and biological systems influencing the transport dynamics of Pickering *** insights hold valuable potential for optimizing transport processes in practical biomedical applications such as drug ***,the desired transport efficiency varies depending on the specific *** instance,while a more rapid transport might be crucial for lymph-node-targeted drug delivery,certain applications requiring a slower release of active components could benefit from the reduced transport efficiency observed with increased particle repulsion or larger intercellular gaps.

关键词： Pickering emulsion Skeletal muscular cells Transport phenomena Dissipative particle dynamics Drug delivery

Research on concrete structure defect repair based on three-dimensional printing

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 731-742页

作者： Yang GU wei LI Xupeng YAO Guangjun liu School of Mechanical Engineering Tongji UniversityShanghai 201804China College of Civil Engineering Tongji UniversityShanghai 200092China Shanghai Engineering Research Center for Safety Intelligent Control of Building Machinery Shanghai 200032China

Quality assurance and maintenance play a crucial role in engineering construction,as they have a significant impact on project *** common issue in concrete structures is the presence of *** enhance the automation level of concrete defect repairs,this study proposes a computer vision-based robotic system,which is based on three-dimensional(3D)printing technology to repair *** system integrates multiple sensors such as light detection and ranging(LiDAR)and *** is utilized to model concrete pipelines and obtain geometric parameters regarding their ***,a convolutional neural network(CNN)is employed with a depth camera to locate defects in concrete ***,a method for coordinate transformation is presented to convert the obtained coordinates into executable ones for a robotic ***,the feasibility of this concrete defect repair method is validated through simulation and experiments.

关键词： concrete defect detection 3D printing deep learning point cloud data

KSKV:Key-Strategy for Key-Value Data Collection with Local Differential Privacy

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3063-3083页

作者： Dan Zhao Yang You Chuanwen Luo ting Chen Yang liu Artificial Intelligence Development Research Center Institute of Scientific and Technical Information of ChinaBeijing100038China Industry Development Department NSFOCUS Inc.BeijingChina School of Information Science and Technology Beijing Forestry UniversityBeijing100083China School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China Institute of Computing Technology China Academy of Railway Sciences Corporation LimitedBeijing10081China

In recent years,the research field of data collection under local differential privacy(LDP)has expanded its focus fromelementary data types to includemore complex structural data,such as set-value and graph ***,our comprehensive review of existing literature reveals that there needs to be more studies that engage with key-value data *** studies would simultaneously collect the frequencies of keys and the mean of values associated with each ***,the allocation of the privacy budget between the frequencies of keys and the means of values for each key does not yield an optimal utility *** the importance of obtaining accurate key frequencies and mean estimations for key-value data collection,this paper presents a novel framework:the Key-Strategy Framework forKey-ValueDataCollection under ***,theKey-StrategyUnary Encoding(KS-UE)strategy is proposed within non-interactive frameworks for the purpose of privacy budget allocation to achieve precise key frequencies;subsequently,the Key-Strategy Generalized Randomized Response(KS-GRR)strategy is introduced for interactive frameworks to enhance the efficiency of collecting frequent keys through group-anditeration *** strategies are adapted for scenarios in which users possess either a single or multiple key-value ***,we demonstrate that the variance of KS-UE is lower than that of existing *** claims are substantiated through extensive experimental evaluation on real-world datasets,confirming the effectiveness and efficiency of the KS-UE and KS-GRR strategies.

关键词： Key-value local differential privacy frequency estimation mean estimation data perturbation