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LRChain:data protection and sharing method of learning archives based on consortium blockchain

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The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 28-42页

作者： lan Lina Gao Yuhan Shi Ruisheng wu Fenfen School of Humanities Beijing University of Posts and TelecommunicationsBeijing 100876China School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Trustworthy Distributed Computing and Service Beijing University of Posts and TelecommunicationsMinistry of EducationBeijing 100876China

Learning archives management in traditional systems faces challenges such as inadequate security,weak tamper resistance,and limited sharing *** address these issues,this paper proposes LRChain,a method based on consortium blockchain,for lifelong learning archives data protection and *** employs a combination of on-chain and off-chain cooperative storage using a consortium chain and inter planetary file system(IPFS)to enhance data security and *** also enables fine-grained verification of learning archives through selective disclosure principles,ensuring privacy protection of sensitive ***,an attributebased encryption(ABE)algorithm is utilized to establish authorized access control for learning archives,facilitating safe and trusted *** evaluations and security analyses demonstrate that this method exhibits decentralization,strong security,tamper resistance,and performs well,effectively meeting the requirements for secure sharing of learning archive data.

关键词： learning archives consortium blockchain collaborative storage secure sharing

Link Prediction Method Fusion with Local Structural Entropy for Directed Network

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Chinese Journal of Electronics 2024年第1期33卷 204-216页

作者： Shuxin LIU Hongchang CHEN lan wu Kai WANG Xing LI People’s Liberation Army Strategic Support Force Information Engineering University

Link prediction utilizes accessible network information to complement or predict the network *** is an important prerequisite for link prediction which means links more likely occurs between two similar nodes. Existing methods utilize the similarity of nodes but neglect of network structure. However the link direction leads to a far more complex structure and contains more information useful than the undirected networks. Most classic methods are difficult to depict the distribution of the network structure with incidental direction so the similarity characteristics of the network structure itself are lost. In this respect, a new method of local structure entropy is proposed to depict the directed structural distribution characteristics, which can be used to evaluate the degree of local structural similarity of nodes and then applied to link prediction methods. Experimental results on 8 real directed networks show that this method is effective for both area under the receiver operating characteristic curve(AUC)and ranking-score measures, and improved predictive capacity of the baseline methodology.

关键词： Correlation Current measurement Area measurement Prediction methods Receivers Benchmark testing Entropy

An Information Hiding Algorithm Based on Bitmap Resource of Portable Executable File

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Journal of Electronic Science and Technology 2012年第2期10卷 181-184页

作者： Jie Xu Li-Jun Feng ya-lan Ye Yue wu School of Computer Science & Engineering University of Electronic Science and Technology of China Chengdu 611731 China

An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable （PE） files. This algorithm has higher security than some traditional ones because of integrating secret data and bitmap resources together. Through analyzing the principle of bitmap resources parsing in an operating system and the layer of resource data in PE files, a safe and useful solution is presented to solve two problems that bitmap resources are incorrectly analyzed and other resources data are confused in the process of data embedding. The feasibility and effectiveness of the proposed algorithm are confirmed through computer experiments.

关键词： Bitmap resources data embedding information hiding portable executable file.

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai Xue lan Xie Chang-Mei wu Qiang Zheng Department of Polymer Materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Carboxyl terminal of rhodopsin kinase is required for the phosphorylation of photo-activated rhodopsin

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Cell Research 1998年第4期8卷 303-310页

作者： YU QING MING ZHI JIE CHENG JIAN ZHAO TIAN HUA ZHOU ya lan wu lan MA GANG PEI(Shanghai Institute of Cell Biology, Chinese Academy of Science, 320 Yue yang Road, Shanghai 200031, China)(Department of Neurobiology, Shanghai Medical University,Shanghai Shanghai Institute of Cell Biology Chinese Academy of Science Shanghai China Department of Neurobiology Shanghai Medical University Shanghai China

Human rhodopsin kinase (RK) and a carboxyl terminus-truncated mutant RK lacking the last 59 amino acids (RKC) were expressed in human embryonic kidney 293 cells to investigate the role of the carboxyl terminus of RK in recognition and phosphorylation of rhodopsin. RKC, like the wild-type RK, was detected in both plasma membranes and cytosolic fractions. The Cterminal truncated rhodopsin kinase was unable to phosphorylate photo-activated rhodopsin, but possesses kinase activity similar to the wild-type RK in phosphorylation of small peptide substrate. It suggests that the truncation did not disturb the gross structures of RK catalytic domain. Our results also show that RKC failed to translocate to photo-activated rod out segments. Taken together,our study demonstrate the carboxyl terminus of RK is required for phosphorylation of photo-activated rhodopsin and strongly indicate that carboxyl-terminus of RK may be involved in interaction with photo-activated rhodopsin.

关键词： Rhodopsin kinase phosphorylation fruncation

Numerical investigation on ball-sealers transport and diversion performance in shale gas horizontal well based on semi-resolved CFD-DEM

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Particuology 2024年第10期93卷 137-153页

作者： Yinjian Huang Jinzhou Zhao lan Ren Ran Lin Jianfa wu Cheng Shen Jianjun wu Bing Li National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Tianfu Yongxing Laboratory Chengdu610213China Shale Gas Research Institute PetroChina Southwest Oil&Gasfield CompanyChengdu610056China PetroChina Coalbed Methane Company Limited Xi’an710082China

In the staged multi-cluster fracturing of shale gas horizontal wells, ball sealers are used to ensure uniform fluid distribution among clusters, a strategy that is both cost-effective and operationally beneficial. Despite these advantages, comprehending the ball sealers' dynamics within the wellbore and their plugging behavior at perforations is still challenging. This complexity results in prediction difficulties regarding their diversion efficiency. To address this, our study utilized a semi-resolved CFD-DEM model based on kernel approximation to simulate the behavior of medium-sized ball sealers in single and multiple cluster scenarios. Our findings from a single cluster scenario reveal that the plugging probability is co-determined by velocity gradients in the fluid ingestion area near the perforation, backflow region, and inertial forces of the ball sealers. As the critical flow rate is achieved, the plugging probability negatively correlated with fluid viscosity and displacement, and positively correlated with the perforation flow ratio (PFR), the difference in particle-fluid density, ball sealer’s diameter, and the ball sealer’s offset from the pipeline center. Temporary plugging control efficiency was used to evaluate the flow balance effect among multiple clusters. The results indicate that an increased number of ball sealers enhances the fault tolerance during the temporary plugging process. Nevertheless, excessive ball sealers might undermine the temporary plugging control efficiency, as perforations with lower fluid inflow rates are unexpectedly plugging. Higher differences in fluid injection rates between clusters led to increased efficiency in temporary plugging control. Premature deployment of ball sealers cannot effectively plug perforations with marginally higher fluid inflow rates, but instead accidently plug intermediate clusters with lower fluid inflow rates. These findings offer a theoretical basis for optimizing the design of ball sealers.

关键词： Gas shale Horizontal wells Ball sealer Semi-resolved CFD-DEM Diversion

Current collectors' effects on the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 suspension electrodes for lithium slurry battery

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Green Energy & Environment 2024年第8期9卷 1306-1313页

作者： Linshan Peng Yufei Ren Zhaoqiang Yin Zhitong Wang Xiangkun wu lan Zhang CAS Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences Hefei University Institute of Mechanics Chinese Academy of Sciences langfang Green Industrial Technology Center

Take after the advantages of lithium-ion battery（LIB） and redox flow battery（RFB）, semi-solid flow battery（SSFB） is a promising electrochemical energy storage device in renewable energy utilization. The flowable slurry electrode realizes decouple of energy and power density,while it also brings about new challenge to SSFBs, electron transport between active material and the out circuit. In this consideration, three types of current collectors（CCs） are applied to study the resistance and electrochemical performances of slurry cathodes within pouch cells for the first time. It proves that the electronic resistance（Re） between slurry electrode and the CC plays a decisive role in SSFB operation, and it is so large when Al foil is adopted that the cell cannot even work. Contact angle between Ketjen black（KB） slurry without active material（AM） and the CC is a preliminarily sign for the Re, the smaller the angle, the lower the resistance, and the better electrochemical performance of the cell.

关键词： Semi-solid flow battery Slurry electrode Current collector Electronic resistance Carbon coated Al

Theoretical design of polyazole based ligands for the separation of Am(Ⅲ)/Eu(Ⅲ)

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Chinese Chemical Letters 2024年第8期35卷 406-412页

作者： Lingling Su Qunyan wu Congzhi Wang Jianhui lan Weiqun Shi School of Nuclear Science and Technology University of South ChinaHengyang 421001China Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

The extraction of radioactive minor actinides(An(Ⅲ))from lanthanides(Ln(Ⅲ))is an extremely impor-tant step in nuclear waste *** ligands with high-performance actinide-selectivity re-mains an essential *** works have reported that some polyazole based ligands exhibit good An(Ⅲ)/Ln(Ⅲ)separation ***,we first evaluated the effects of different polyazole side chains on the Am(Ⅲ)/Eu(Ⅲ)selectivity by exploring three pyridine-derived polyazole ligands L^(1),L^(2)and L^(3)with 1,2,4-triazole,1,2,3-triazole,and pyrazole side chains,respectively,using scalar relativistic theoretical *** coordination structures,bonding properties and thermodynamic behaviors of AmL(NO_(3))_(3)and EuL(NO_(3))_(3)complexes were investigated,which clarifies that the side chains do affect the electronic structure of ligand and its selectivity for Am(Ⅲ)/Eu(Ⅲ)***,L^(1)with 1,2,4-triazole side chains exhibited the highest selectivity for Am(Ⅲ)over Eu(Ⅲ)while the lowest complexation ability for metal ions among the three pyridine-derived polyazole ***,we designed a new ligand L^(4)con-taining 1,2,4-triazole side chains and a preorganized phenanthroline ***,such a new ligand was verified to show stronger complexation ability and higher selectivity for Am(Ⅲ)/Eu(Ⅲ)ions than L^(1).This work clarifies the complexation nature of polyazole based ligands with Am(Ⅲ)/Eu(Ⅲ)ions and provides design strategies for highly efficient polyazole based ligands for An(Ⅲ)/Ln(Ⅲ)separation.

关键词： Solvent extraction Am(Ⅲ)/Eu(Ⅲ)separation Polyazole based ligands Design strategy Density functional theory

Erythropoietin Receptor Positive Circulating Progenitor Cells and Endothelial Progenitor Cells in Patients with Different Stages of Diabetic Retinopathy

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Chinese Medical Sciences Journal 2011年第2期26卷 69-76页

作者： Liu-mei Hu Xia Lei Bo Ma Yu Zhang yan yan ya-lan wu Ge-zhi Xu Wen Ye Ling Wang Guo-xu Xu Guo-tong Xu Wei-ye Li Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China Tongji Eye Institute and Department of Regenerative Medicine Tongji University School of Medicine Shanghai 200092 China Laboratory of Clinical Visual Sciences Institute of Health Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences ＆ Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Ophthalmology Eye and ENT Hospital Fudan University Shanghai 200031 China Department of Ophthalmology Huashan Hospital Affiliated to Fudan University Shanghai 200040 China Department of Ophthalmology Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Ophthalmology Second Affiliated Hospital of Soochow University Suzhou Jiangsu 215004 China Department of Ophthalmology Drexel University College of Medicine Philadelphia PA 19107 USA

Objective To investigate the possible involvement of erythropoietin （EPO）/erythropoietin receptor （EPOR） system in neovascularization and vascular regeneration in diabetic retinopathy （DR）. Methods EPOR positive circulating progenitor cells （CPCs： CD34^＋） and endothelial progenitor cells （EPCs： CD34^＋KDR^＋） were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes （n=7）, non-prolif- erative DR （NPDR, n=7）, proliferative DR （PDR, n=8）, and PDR complicated with diabetic nephropathy （PDR-DN, n=7）. Results The numbers of EPOR^＋ CPCs and EPOR^＋ EPCs were reduced remarkably in NPDR corn pared with the control group （both P（0.01）, whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^＋ CPCs in CPCs （NPDR vs. control, P（0.01） and that of EPOR^＋ EPCs in EPCs （NPDR vs. control, P〈0.05）. Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^＋ EPCs associated with ischemia.

关键词： circulating progenitor cells endothelial progenitor cells erythropoietin re-ceptor diabetic retinopathy