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Acta Mechanica Sinica 2012年第3期28卷 891-903页

作者： de-chang li Bao-Hua Ji Biomechanics and Biomaterials Lab Department of Applied MechanicsBeijing Institute of TechnologyKey Laboratory.of Dynamics and Control of Flight VehicleMinistry of Education100081 BeijingChina

Jarzynski＇ identity （JI） method was suggested a promising tool for reconstructing free energy landscape of biomolecular interactions in numerical simulations and ex- periments. However, JI method has not yet been well tested in complex systems such as ligand-receptor molecular pairs. In this paper, we applied a huge number of steered molec- ular dynamics （SMD） simulations to dissociate the protease of human immunodeficiency type I virus （HIV-1 protease） and its inhibitors. We showed that because of intrinsic com- plexity of the ligand-receptor system, the energy barrier pre- dicted by JI method at high pulling rates is much higher than experimental results. However, with a slower pulling rate and fewer switch times of simulations, the predictions of JI method can approach to the experiments. These results sug- gested that the JI method is more appropriate for reconstruct- ing free energy landscape using the data taken from experi- ments, since the pulling rates used in experiments are often much slower than those in SMD simulations. Furthermore, we showed that a higher loading stiffness can produce higher precision of calculation of energy landscape because it yields a lower mean value and narrower bandwidth of work distri- bution in SMD simulations.

关键词： Molecular dynamics simulation. Single molecu-lar interaction ~ Molecular biomechanics ~ Steered moleculardynamics ~ Free energy calculation

Epithelial-mesenchymal transition in colorectal cancer tissue of patients with Lynch syndrome

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World Journal of Gastroenterology 2014年第1期20卷 250-257页

作者： Guo-li Gu Xiao-Quan Zhu Xue-Ming Wei li Ren de-chang li Shi-lin Wang department of General Surgery the Air Force General Hospital PLA the Affiliated Hospital of Aviation Medical Institute PLA Air Force department of Pathology the Air Force General Hospital PLA

AIM: To explore the epithelial-mesenchymal transition (EMT) in tissue from patients with Lynch syndrome, and to interpret biological behaviour of Lynch syndrome.

关键词： Lynch syndrome, Mutation, Epithelial-mesenchymal transition, β -catenin, Mismatch repair gene

Cobalt single atoms supported on monolithic carbon with a hollow-on-hollow architecture for efficient transfer hydrogenations

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Nano Research 2023年第8期16卷 11358-11365页

作者： Xiangyi Gong de-chang li Qian Zhang Wenquan Wang Zhengbin Tian Ge Su Minghua Huang Guang-Hui Wang School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China University of Chinese Academy of Sciences Beijing 100049China

Single-atom catalysts(SACs)have received considerable attention in hydrogenation of nitroaromatic compounds to aromatic *** order to enhance the exposure of single atoms and overcome the mass transfer limitation,construction of hierarchical porous supports for single atoms is highly ***,we report a straightforward method to synthesize Co single-atoms supported on a hollow-on-hollow structured carbon monolith(Co_(1)/HOHC-M)by pyrolysis ofα-cellulose monolith loaded with PS-core@ZnCo-zeolite imidazolate frameworks-shell nanospheres(PS@Zn-ZIFs/α-cellulose).The hollow-on-hollow structure consists of a large hollow void with a diameter of~290 nm(derived from the decomposition of polystyrene(PS)nanospheres)and a thin shell with hollow spherical pores with a diameter of~10 nm(derived from the evaporation of ZnO nanoparticles that are in-situ formed during pyrolysis in the presence of CO_(2)fromα-cellulose decomposition).Benefitting from the hierarchically porous architecture,the Co_(1)/HOHC-M exhibits excellent catalytic performance(reaction rate of 421.6 mmol·gCo^(-1)·h^(−1))in the transfer hydrogenation of nitrobenzene to aniline,outperforming the powdered sample of Co_(1)/HCS without the hollow spherical mesopores(reaction rate of 353.8 mmol·gCo^(-1)·h^(−1)).It is expected that this strategy could be well extended in heterogeneous catalysis,given the wide applications of porous carbon-supported single-atom catalysts.

关键词： hollow-on-hollow Co single-atoms nitrobenzene transfer hydrogenation

Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle

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China Foundry 2024年第2期21卷 185-196页

作者： Wei-li Wu chang-gui Cheng Yang li Shi-fa Wei de-li Chen The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081China Technology Center Fushun Special Steel Co.Ltd.Fushun 113001LiaoningChina

In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab *** order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT *** show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either *** the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes *** increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction.

关键词： continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate

SIMULATION OF 3-D FLOW AROUND A VAN-BODY TRUCK WITH RNG K-ε TURBULENCE MOdeL

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Journal of Hydrodynamics 2001年第4期13卷 98-101页

作者： Du, Guang-Sheng Wang, de-chang Lei, li Zhou, lian-Di Coll. of Water Conservancy Wuhan Univ. Ji'nan 250061 China

It is proved that the calculation precision of the outside flow field of the van-body truck using PNG k-Ε turbulence model is higher than that using standard k-Ε turbulence model by means of experiments. The calculation results of the outside flow field of a certain domestic van-body truck are given. And by analyzing and comparing the different tail flow plots, the tail flow structural characteristics and the relationship between the position and the intensity of the tail vortex and the aerodynamic drag is obtained, which can direct the design of the outside aerodynamic shape of the van-body truck.

关键词： Computer simulation Drag Mathematical models Turbulent flow

Near-infrared non-fused electron acceptors for efficient organic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang Ma Xinyu He Tianyi Chen de-li Ma Hongzheng Chen chang-Zhi li State Key Laboratory of Silicon and Advanced Semiconductor Materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.

关键词： Organic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

Targeted multi-agent communication algorithm based on state control

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defence Technology（防务技术） 2024年第1期31卷 544-556页

作者： li-yang Zhao Tian-qing chang Lei Zhang Jie Zhang Kai-xuan Chu de-peng Kong department of Weaponry and Control Army Academy of Armored ForcesBeijing100072China Unit 92942 Beijing100161China

As an important mechanism in multi-agent interaction,communication can make agents form complex team relationships rather than constitute a simple set of multiple independent ***,the existing communication schemes can bring much timing redundancy and irrelevant messages,which seriously affects their practical *** solve this problem,this paper proposes a targeted multiagent communication algorithm based on state control(SCTC).The SCTC uses a gating mechanism based on state control to reduce the timing redundancy of communication between agents and determines the interaction relationship between agents and the importance weight of a communication message through a series connection of hard-and self-attention mechanisms,realizing targeted communication message *** addition,by minimizing the difference between the fusion message generated from a real communication message of each agent and a fusion message generated from the buffered message,the correctness of the final action choice of the agent is *** evaluation using a challenging set of Star Craft II benchmarks indicates that the SCTC can significantly improve the learning performance and reduce the communication overhead between agents,thus ensuring better cooperation between agents.

关键词： Multi-agent deep reinforcement learning State control Targeted interaction Communication mechanism

Interplay of RNA-binding proteins controls germ cell development in zebrafish

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Journal of Genetics and Genomics 2024年第9期51卷 889-899页

作者： de-li Shi Laboratory of developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants,called germ plasm,confer germline fate in the early *** studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell ***-binding proteins,acting in concert with other germ plasm components,play essential roles in the organization of the germ plasm and the specification,migration,maintenance,and differentiation of primordial germ *** loss of their functions impairs germ cell formation and causes sterility or sexual *** is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ ***,the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell *** failure to control the developmental outcome of germ cells disrupts the formation of gametes,it is important to gain a complete picture of regulatory mechanisms operating in the germ cell *** review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

关键词： Germplasm Primordialgerm cell Germlinestem cell Gametogenesis Zebrafish RNA-binding protein Posttranscriptional gene expression Translational activation and repression

Aerodynamic Performance of Three Flapping Wings with Unequal Spacing in Tandem Formation

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Journal of Bionic Engineering 2024年第4期21卷 1662-1676页

作者： Min chang Ziyi Xu Zengshuang Chen li li Xueguang Meng Unmanned System Research Institute National Key Laboratory of Unmanned Aerial Vehicle TechnologyNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China Xi’an Aeronautics Computing Technique Research Institute Aviation Industry Corporation of ChinaXi’an710076People’s Republic of China

To better understand the aerodynamic reasons for highly organized movements of flying organisms,the three-flapping wing system in tandem formation was studied numerically in this *** from previous relevant studies on the multiple flapping wings that are equally spaced,this study emphasizes the impact of unequal spacing between individuals on the aerodynamics of each individual wing as well as the whole *** is found that swapping the distance between the first and second wing with the distance between the second wing and the rearmost wing does not affect the overall aerodynamic performance,but significantly changes the distribution of aerodynamic benefits across each *** the whole flapping cycle,three effects are at *** narrow channel effect and the downwash effect can promote and weaken the wing lift,respectively,while the wake capture effect can boost the *** also shows that these effects could be manipulated by changing the spacing between adjacent *** findings provide a novel way for flow control in tandem formation flight and are also inspiring for designing the formation flight of bionic aircraft.

关键词： Three flapping wings Unequal spacing Aerodynamic performance Tandem formation

A Generalized MSST Algorithm for Counting Points of Elliptic Curves over F_(p)^(n)

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Journal of Systems Science & Complexity 2024年第4期37卷 1738-1754页

作者： li Xiao LV chang PAN Zhizhong Key Laboratory of Cyberspace Security defense Institute of Information EngineeringChinese Academy of SciencesBeijing 100085China School of Cyber Security University of Chinese Academy of SciencesBeijing 100085China Huawei Technologies Co. Ltd.Shenzhen 518129China

Elliptic curve cryptography is an important part of nowaday's public key *** points of elliptic curves over finite fields is of great significance to the selection of safety *** present,there are many p-adic algorithms,such as SST algorithm,generalized AGM algorithm,Kedlaya algorithm,etc.,which can deal with the situation of finite fields of small *** this paper,the authors generalize the MSST algorithm of characteristic 2 to general fields of odd characteristic,and propose the generalized MSST *** generalized MSST algorithm is achieved by combining the advantages of the SST algorithm and the generalized AGM *** the time complexity of the multiplication of two n-bit numbers is denoted as O((n)^(μ)),then the time complexity of the generalized MSST algorithm is O(n^(2μ+1/1+μ)),which is the same as the improved SST *** practical experiments,the running time of the generalized MSST algorithm is less than that of the improved SST algorithm.

关键词： Elliptic curve generalized AGM algorithm generalized MSST algorithm SST algorithm