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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model

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Journal of Magnesium and Alloys 2024年第1期12卷 384-393页

作者： Baoxiang zhang wen zhang Fei zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang zhang Department of Sports Medicine Chinese PLA General HospitalBeijing 100853China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Medical School of PLA Beijing 100853China Institute of Orthopedics Chinese PLA General HospitalBeijing Key Lab of Regenerative Medicine in OrthopedicsKey Lab of Musculoskeletal Trauma&War Injuries of Chinese PLABeijing 100853China

Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional *** the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as *** shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after *** Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to *** observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture *** the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks *** collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous *** vivo degradation of the magnesium alloy wire was completed within 12 *** results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair.

关键词： Rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface

Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-wen Yuan Zhao-Qiang Shen yi-ying Wang Yuan-Zhu Wang Zhen-Bo Su wen-Ke Ren Shao-Peng Tang Hao Zhou Chi zhang Zhi-Ping Jin Lei Feng yi-Zhong Fan Da-Ming Wei Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the James Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei James Webb Space Telescope

Energy-based Directional Pilot Protection for Distribution Networks with IBDGs Considering Unmeasured Load Switching

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 139-150页

作者： Chenghan Zhou Guibin Zou Shuo zhang Xuhui wen Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250061China

Inverter-based distributed generations(IBDGs)are the main approach to utilizing clean energy in distribution networks(DNs).Compared with synchronous source,fault response of IBDG is very *** a result,in DNs with high penetration of IBDGs,legacy protection schemes will no longer be *** this paper,an energy-based directional pilot protection scheme suitabie for DNs with IBDGs is *** scheme considers the large range of phase angle caused by IBDG integration and uses improved energy polarity criterion to determine fault *** addition,magnitude of energy is used to distinguish between faults and load switching to overcome maloperation of directional pilot protection caused by internal unmeasured load *** proposed scheme first uses local measured information to determine fault direction sign and then exchanges the direction sign with the remote *** scheme does not require high-bandwidth communication and strict data synchronization,so it can be implemented at a low ***,simulation studies verify effectiveness of the proposed scheme.

关键词： Distribution network energy polarity inverterbased distributed generation pilot protection unmeasured load

Potential for soil carbon sequestration under conservation agriculture in a warming climate

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Science Bulletin 2024年第13期69卷 2030-2033页

作者： Lijun Yu wen zhang Jingjing Liu wenjuan Sun Qing zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Anyang Meteorological Service Anyang 455000China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Agricultural soil has numerous links with climate *** comprises a substantial part of farming systems that are affected by climate change and can significantly impact food security[1].An increase in the soil carbon(C)stock is associated with an increase in the crop ***,agricultural soil remains a source for all three major greenhouse gases(GHGs),i.e.,carbon dioxide(CO_(2)),methane and nitrous oxide,which contributes directly to climate *** addition,enhancing soil C sequestration in agricultural land could offset GHG emissions,promote more sustainable and climate-resilient agricultural systems.

关键词： soil warming agricultural

Machine Learning Security Defense Algorithms Based on Metadata Correlation Features

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Computers, Materials & Continua 2024年第2期78卷 2391-2418页

作者： Ruchun Jia Jianwei zhang yi Lin College of Computer Science Sichuan UniversityChengdu610065China

With the popularization of the Internet and the development of technology,cyber threats are increasing day by *** such as malware,hacking,and data breaches have had a serious impact on *** network security environment in the era of big data presents the characteristics of large amounts of data,high diversity,and high real-time *** security defense methods and tools have been unable to cope with the complex and changing network security *** paper proposes a machine-learning security defense algorithm based on metadata association *** control over unauthorized users through privacy,integrity,and *** user model is established and the mapping between the user model and the metadata of the data source is *** analyzing the user model and its corresponding mapping relationship,the query of the user model can be decomposed into the query of various heterogeneous data sources,and the integration of heterogeneous data sources based on the metadata association characteristics can be *** and classify customer information,automatically identify and perceive sensitive data,build a behavior audit and analysis platform,analyze user behavior trajectories,and complete the construction of a machine learning customer information security defense *** experimental results show that when the data volume is 5×103 bit,the data storage integrity of the proposed method is 92%.The data accuracy is 98%,and the success rate of data intrusion is only 2.6%.It can be concluded that the data storage method in this paper is safe,the data accuracy is always at a high level,and the data disaster recovery performance is *** method can effectively resist data intrusion and has high air traffic control *** can not only detect all viruses in user data storage,but also realize integrated virus processing,and further optimize the security defense effect of user big data.

关键词： Data-oriented architecture metadata correlation features machine learning security defense data source integration

Synthesis of Diverse Oxetane Amino Acids via Visible-Light-Induced Photocatalytic Decarboxylative Giese-Type Reaction

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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi yi Wan Yongqiang zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Vanadium(V) Complexes Containing Unsymmetrical N-Heterocyclic Carbene Ligands: Highly Efficient Synthesis and Catalytic Behavior towards Ethylene/Propylene Copolymerization

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Chinese Journal of Polymer Science 2024年第1期42卷 32-41,I0006页

作者： yi-Cong Wang Hui Zhat Pei-yi Cheng Shu zhang Xiang-Wei Liu yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBejing 100029China

The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with VOCl_(3).The total isolated yield of VOCl_(3)[1,3-(2,4,6-Me_(3)C_(6)H_(2))_(2)(NCH=)_(2)C:](V4') reached 86% by transmetallation reaction,which is much higher than that(48%) by direct coordination *** methodology has also been used to synthesize the novel vanadium complexes containing unsymmetrical NHC ligands of VOCl_(3)[PhCH_(2)NCH=CHNR)C:](V5',R=2,4,6-Me_(3)C_(6)H_(2);V6',R=2,4-Me_(2)-6-Ph-C_(6)H_(2);V7',R=2,6-^(i)Pr_(2)-C_(6)H_(3)) with high yield,which could not be obtained by direct coordination *** catalytic activity and copolymerization ability would be improved by introducing unsymmetrical NHC ligands due to their less steric bulky *** vanadium complex V5' containing unsymmetrical NHC ligand exhibits higher catalytic activity(3.7×10^(5)g_(copolymer)·mol^(-1) of V·h^(-1)) than that of V4' containing symmetrical NHC ***,the higher propylene incorporation ratio(45.6 mol%) in the copolymers of ethylene with propylene could be obtained by using V5' than that(39.9%) by using V4'.The results would provide a highly efficient strategy for the synthesis of early transition metal complexes containing versitile NHC ligands,affording the catalyst with both high catalytic activity and copolymerization ability for the synthesis of high performance polyolefin elastomers.

关键词： Vanadium complex N-heterocyclic carbene ligand Transmetallation reaction Copolymerization of ethylene with propylene

Rapid report of source parameters of 2023 M6.2 Jishishan,Gansu earthquake sequence

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Earth and Planetary Physics 2024年第2期8卷 436-443页

作者： ZhiGao Yang Jie Liu yingying zhang wen Yang XueMei zhang China Earthquake Networks Center Beijing 100045China

The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake *** was located in the northern part of the north−south seismic zone,which is a key area for earthquake monitoring in *** newly built dense strong motion stations in this area provide unprecedented conditions for high-precision earthquake relocation,especially the earthquake focal *** paper uses the newly built strong motion and traditional broadband seismic networks to relocate the source locations of the M3.0 and above aftershocks and to invert their focal *** horizontal error of earthquake location is estimated to be 0.5−1 km,and the vertical error is 1−2 *** focal depth range of aftershocks is 9.6−14.6 km,distributed in a 12-km-long strip with SSE *** in the south are more concentrated horizontally and vertically,while aftershocks in the north are more *** focal mechanisms of the main shock and aftershocks are relatively consistent,and the P-axis orientation is consistent with the regional strain *** is a seismic blank area of M3.0 and above,about 3−5 km between the main shock and *** is suggested that the energy released by the main shock rupture is concentrated in this *** on the earthquake location and focal mechanism of the main shock,it is inferred that the Northern Lajishan fault zone is the seismogenic structure of the main shock,and the main shock did not occur on the main fault,but on a secondary *** initial rupture depth and centroid depth of the main shock were 12.8 and 14.0 km,*** source rupture depth may not be the main reason for the severe earthquake disaster.

关键词： Jishishan earthquake earthquake relocation focal mechanism strong motion data

Spontaneous anchoring Cl into α-Co（OH）2 as efficient and stable oxygen reduction electrocatalysts for seawater battery

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Rare Metals 2024年第7期43卷 3074-3083页

作者： Wang Zheng Xue-Rong Zheng Qi Lu Yan-Hui Cao Yang Wang Hai-Peng Fu Jin-Feng zhang yi-Da Deng wen-Bin Hu School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin University State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan University Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern University

Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,***,the oxygen reduction reaction（ORR） activity and stability of electrocatalysts can be easily deactivated due to the severe Cl-permeation and corrosion in seawater ***,we developed a structural buffer engineering strategy by spontaneously anchoring Cl-into α-Co（OH）2as efficient and stable ORR electrocatalysts,in which the ultrathin α-Co（OH）2nanosheets were synthesized using an ultrafast solution high-temperature shock（SHTS） *** large lattice space（～ 0.8 nm） of layered α-Co（OH）2ensured the spontaneously penetration of Cl-into the lattice structure and replaced part of OH-to form α-Co（OH）*** continuous leaching and compensating of saturated Cl in α-Co（OH）2-xClxcould enhance the Cl-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater *** α-Co（OH）2-xClxseawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts of α-Co（OH）2and of β-Co（OH）2with no Cl-penetrating and no buffer *** α-Co（OH）2-xClx-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g-1.

关键词： Seawater battery Oxygen reduction electrocatalyst Solution high-temperature shock Structural buffer engineering