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Chinese Journal of Chemistry 2024年第18期42卷 2133-2139页

作者： Yanping Cai Shengjie Jiang xin xu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochowUniversitySuzhouJiangsu215123China

Background and Originality Content The catalytic hydrosilylation of unsaturated hydrocarbons,facilitated by transition metal(TM),is widely recognized as a proficient technique for the synthesis of high-value organosilicon compounds'ti-4l over the past few decades,the most dominant *** in hydrosilylation processes have been constituted by pre-Ccious metar complexesroceinerecent vears omore sustainabile earth-abundant metal catalysts have received increased attentionj2-14l The classcal mechanism of transition metal-catalyzed hydrosilylation is generally accomplished through a series of fundamental processes(Scheme 1a),including(i)coordination and oxidative addition of Si-H bond to a low-valent metal center to form e.g.,o-complex or silyl metal hydride;(ii)insertion of.C-C multipe bonds intometal-hdridelsior metal-silicon bond;jiol and(ii)reductive elimination that forwards the hydrosilylated product with Markovnikov or anti-Markovnikov selectivity.

关键词： Heterometallic complex Cooperative effect Hydrosilylation Magnesium Nickel hydride

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： LIU Lei LIU Jian-cheng LI xin xu Li-xin ZHANG Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Traction force with extracellular matrix mediated by cytoskeleton influences metastasis through SLC8A1 induced Wnt-b-catenin pathway in endometrial cancer

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Genes & Diseases 2024年第5期11卷 98-101页

作者： xingchen Li xin xu Jianliu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Department of Obstetrics and Gynecology Beijing ChaoYang HospitalCapital Medical UniversityBeijing 100020China

Endometrial cancer(EC)is one of the most prominent malignancies in ***,despite these advancements in understanding EC pathogenesis,mortality rates have not *** force(TF)refers to endogenous mechanical forces exerted by cells.1 These forces act on the extracellular matrix and the extracellular tumor microenvironment through focal adhesions,thereby regulating cell proliferation and ***,the TF characteristics of endometrial cancer cells and their heterogeneity remain unclear.

关键词： endometrial metastasis endogenous

Towards direct superlubricity and superlow wear via amino modification of polyhydroxy alcohol solutions

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Friction 2024年第9期12卷 1980-1990页

作者： Qiang MA Chengpeng YAN Rui YAN xin xu Haifeng WANG State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China Chongqing Innovation Center Northwestern Polytechnical UniversityChongqing 401135China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China

Friction remains as the primary mode of energy dissipation and components wear,and achieving superlubricity shows high promise in energy conservation and lifetime wear *** results in this work demonstrate that direct superlubricity combined with superlow wear can be realized for steel/Si_(3)N_(4)contacts on engineering scale when polyhydroxy alcohol solution was selectively modified by amino *** direct superlubricity occurs because 3-amino-1,2-propanediol molecules at the friction interface could be induced to rotate and adsorb vertically on the friction surface,forming in-situ thick and dense molecular films to passivate the asperity ***,amino modification is also conducive to improving the lubrication state from boundary to mixed lubrication regime by strengthening the intermolecular hydrogen bonding interaction,presenting enhanced load-bearing capability and reduced direct solid asperity ***,direct superlow average friction of 0.01 combined with superlow wear are achieved *** design principle of direct superlubricity and superlow wear in this work indeed offers an effective strategy to fundamentally improve energy efficiency and provide lifetime wear protection for moving mechanical assemblies.

关键词： direct superlubricity amino modification molecular layer superlow wear

Safe Efficient Policy Optimization Algorithm for Unsignalized Intersection Navigation

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2011-2026页

作者： Xiaolong Chen Biao xu Manjiang Hu Yougang Bian Yang Li xin xu State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body the College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body the College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082 Wuxi Intelligent Control Research Institute(WICRI)of Hunan University Wuxi 214115China College of Intelligence Science and Technology Institute of Unmanned SystemsNational University of Defense TechnologyChangsha 410073China

Unsignalized intersections pose a challenge for autonomous vehicles that must decide how to navigate them safely and *** paper proposes a reinforcement learning(RL)method for autonomous vehicles to navigate unsignalized intersections safely and *** method uses a semantic scene representation to handle variable numbers of vehicles and a universal reward function to facilitate stable learning.A collision risk function is designed to penalize unsafe actions and guide the agent to avoid them.A scalable policy optimization algorithm is introduced to improve data efficiency and safety for vehicle learning at *** algorithm employs experience replay to overcome the on-policy limitation of proximal policy optimization and incorporates the collision risk constraint into the policy optimization *** proposed safe RL algorithm can balance the trade-off between vehicle traffic safety and policy learning *** intersection scenarios with different traffic situations are used to test the algorithm and demonstrate its high success rates and low collision rates under different traffic *** algorithm shows the potential of RL for enhancing the safety and reliability of autonomous driving systems at unsignalized intersections.

关键词： Autonomous driving decision-making reinforcement learning(RL) unsignalized intersection

Research progress on intelligent operation and maintenance of bridges

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 173-187页

作者： Wanshui Han Gan Yang Shizhi Chen Kai Zhou xin xu School of Highway Chang'an UniversityXi'an 710064China

In the context of the increasing scale of bridges and the increasing service life of bridges,it is very important to carry out efficient,accurate and intelligent bridge operation and *** recent years,advanced equipment,technology and intelligent algorithms have developed *** is necessary to apply advanced equipment and algorithms to bridge operation and maintenance business to facilitate the digitalization and intelligence of bridge operation and *** grasp the research progress on the bridge intelligent operation and maintenance,this paper summarizes the research progress in recent years from the aspects of intelligent detection equipment and technology,intelligent monitoring equipment and technology,intelligent data analysis,intelligent evaluation and early warning,and intelligent repair and *** to the review,more and more smart devices have been used to replace human beings to detect dangerous and hidden bridge *** the same time,image processing,radar and other technologies have been used to analyze component damage more objectively and *** solve the shortcomings of traditional sensors such as short life and low robustness,more non-contact measurement methods have been *** have proposed various intelligent algorithms to process the massive amount of bridge health monitoring data to improve the quality of the *** achieve the rapid perception of bridge status and timely early warning of structural abnormalities,different from traditional theoretical calculations,scholars have tried to use data-driven methods to intelligently evaluate and early warning of bridge structural *** terms of intelligent repair and maintenance,more intelligent algorithms have been used to optimize structural maintenance strategies and determine the best maintenance time by integrating multisource heterogeneous *** these provide strong support for the automation,digitization and intelligence o

关键词： Bridge engineering Bridge intelligent operation and maintenance Intelligent equipment Technology and algorithms

A deep Koopman operator-based modelling approach for long-term prediction of dynamics with pixel-level measurements

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 178-196页

作者： Yongqian Xiao Zixin Tang xin xu xinglong Zhang Yifei Shi College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina

Although previous studies have made some clear leap in learning latent dynamics from high-dimensional representations,the performances in terms of accuracy and inference time of long-term model prediction still need to be *** this study,a deep convolutional network based on the Koopman operator(CKNet)is proposed to model non-linear systems with pixel-level measurements for long-term *** adopts an autoencoder network architecture,consisting of an encoder to generate latent states and a linear dynamical model(i.e.,the Koopman operator)which evolves in the latent state space spanned by the *** decoder is used to recover images from latent *** to a multi-step ahead prediction loss function,the system matrices for approximating the Koopman operator are trained synchronously with the autoencoder in a mini-batch *** this manner,gradients can be synchronously transmitted to both the system matrices and the autoencoder to help the encoder self-adaptively tune the latent state space in the training process,and the resulting model is time-invariant in the latent ***,the proposed CKNet has the advantages of less inference time and high accuracy for long-term *** are per-formed on OpenAI Gym and Mujoco environments,including two and four non-linear forced dynamical systems with continuous action *** experimental results show that CKNet has strong long-term prediction capabilities with sufficient precision.

关键词： deep neural networks image motion analysis image sequences sequential estimation

Lipid metabolism, amino acid metabolism, and prostate cancer: a crucial metabolic journey

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Asian Journal of Andrology 2024年第2期26卷 123-134页

作者： Lin Chen Yu-xin xu Yuan-Shuo Wang Jian-Liang Zhou School of Pharmacy Hangzhou Normal UniversityHangzhou 311121China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province Hangzhou Normal UniversityHangzhou 311121China School of Pharmacy Guangxi Medical UniversityNanning530021China

Prostate cancer(PCa)is one of the most common malignancies in males worldwide,and its development and progression involve the regulation of multiple metabolic *** in lipid metabolism affect the proliferation and metastatic capabilities of PCa *** cells increase lipid synthesis and regulate fatty acid oxidation to meet their growth and energy ***,changes occur in amino acid metabolism in *** cells exhibit an increased demand for specific amino acids,and they regulate amino acid transport and metabolic pathways to fulfill their proliferation and survival *** changes are closely associated with disease progression and treatment response in PCa ***,a comprehensive investigation of the metabolic characteristics of PCa is expected to offer novel insights and approaches for the early diagnosis and treatment of this disease.

关键词： amino acid metabolism lipid metabolism metabolic pathways prostate cancer treatment strategies

Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution

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Opto-Electronic Advances 2024年第6期7卷 41-56页

作者： xin xu Qin Luo Jixiang Wang Yahui Song Hong Ye xin Zhang Yi He Minxuan Sun Ruobing Zhang Guohua Shi School of Biomedical Engineering(Suzhou) Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of ScienceSuzhou 215163China

Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 *** restriction poses a challenge when attempting to simultaneously analyze various parts of a sample,such as different brain *** addition,conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in *** we present a novel mesoscopic objective lens with an impressive field of view of 8 mm,a numerical aperture of 0.5,and a working wavelength range from 400 to 1000 *** achieved a resolution of 0.74μm in fluorescent beads *** versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system,a confocal laser scanning system,and a two-photon imaging *** mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution.

关键词： mesoscopic objective lens large field-of-view high resolution multi-wavelength wide-field microscopy confocal laser scanning microscopy

Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming Zhou Kaiwen Li Tao Zhang Ling Wang xin xu Xiangke Liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning