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Total hip arthroplasty after core decompression: Time-to-event analysis and risk factors

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中华医学杂志(英文版) 2024年第16期137卷 1988-1990页

作者： Li Chengsi Wang Tianyu Wu Dongwei Guo Haichuan Yang Zhenbang Cheng Xinqun Zhu yanbin Zhang Yingze Department of Orthopedic Surgery Therd Hospital Hebei Medical University Shijiazhuang Hebei China Orthopedic Research Institute of Hebei Province Key Laboratory of Biomechanics of Hebei Province Shijiazhuang Hebei China

A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu fu Nicola Baresi Roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

Low-Complexity Reconstruction of Covariance Matrix in Hybrid Uniform Circular Array

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China Communications 2024年第3期21卷 66-74页

作者： fu Zihao Liu Yinsheng Duan Hongtao Information School Communication University of ChinaBeijing 100024China Beijing Institute of Electronic System Engineering Beijing 100854China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China Beijing Radio Monitoring Station of State Radio Monitoring Center(SRMC) Beijing 100037China

Spatial covariance matrix(SCM) is essential in many multi-antenna systems such as massive multiple-input multiple-output(MIMO). For multi-antenna systems operating at millimeter-wave bands, hybrid analog-digital structure has been widely adopted to reduce the cost of radio frequency *** this situation, signals received at the antennas are unavailable to the digital receiver, and as a consequence, traditional sample average approach cannot be used for SCM reconstruction in hybrid multi-antenna systems. To address this issue, beam sweeping algorithm(BSA) which can reconstruct the SCM effectively for a hybrid uniform linear array, has been proposed in our previous works. However, direct extension of BSA to a hybrid uniform circular array(UCA)will result in a huge computational burden. To this end, a low-complexity approach is proposed in this paper. By exploiting the symmetry features of SCM for the UCA, the number of unknowns can be reduced significantly and thus the complexity of reconstruction can be saved accordingly. furthermore, an insightful analysis is also presented in this paper, showing that the reduction of the number of unknowns can also improve the accuracy of the reconstructed SCM. Simulation results are also shown to demonstrate the proposed approach.

关键词： hybrid array millimeter-wave spatial covariance matrix uniform circular array

Nanotechnology approaches towards biodeterioration-resistant wood:A review

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Journal of Bioresources and Bioproducts 2024年第1期9卷 3-26页

作者： Ayyoob Arpanaei Qiliang fu Tripti Singh Scion Private Bag 3020Rotorua 3046New Zealand Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China

Wood can be a suitable alternative to energy-intensive materials in various ***-ertheless,its susceptibility to weathering and decay has significantly hindered the broad adop-tion of the most commercially significant wood *** current solutions do tackle certain challenges,they often come with disadvantages like high costs,environmental risks,and/or ***-based methods can be employed to mitigate these weaknesses and create durable,sustainable wood *** this review,we delve into cutting-edge advance-ments in the development of biodeterioration-resistant wood through innovative nanotechnol-ogy *** methods usually involve the application of nanomaterials,either pos-sessing biocidal properties or serving as carriers for *** systematically describe these approaches and compare them to conventional wood modification ***,this re-view provides a brief overview of the prevalent biodeteriorating organisms and their mechanisms of action,which notably impact the development and choice of a suitable strategy for wood mod-ification/*** the requirements of biodeteriorating organisms for growth and wood degradation,it is expected that the new nanotechnology-based approaches to enhance wood dura-bility may provide innovative broad-spectrum biocidal *** systems can simulta-neously induce alterations in the physicochemical properties of wood,thereby constraining the availability of the growth *** alterations can efficiently inhibit the biodeterio-ration process by decreasing water absorption,restricting access to the wood components,and reducing void spaces within the wood ***,this review highlights the new oppor-tunities,challenges,and perspectives of nanotechnology methods for biodeterioration-resistant wood,through which some techno-economic,environmental and safety aspects associated with these methods are addressed.

关键词： Wood durability Decay Wood modification Biodeterioration mechanisms Biocides Wood nanotechnology

Oligodendrocytes in central nervous system diseases:the effect of cytokine regulation

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Neural Regeneration Research 2024年第10期19卷 2132-2143页

作者： Chengfu Zhang Mengsheng Qiu Hui fu Center for Cognition and Brain Disorders The Affiliated Hospital of Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Psychiatry National Clinical Research Center for Mental Disordersand National Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Institute of Life Sciences Key Laboratory of Organ Development and Regeneration of Zhejiang ProvinceCollege of Life and Environment SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina Key Laboratory of Aging and Cancer Biology of Zhejiang Province School of Basic Medical SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina

Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular functions such as migration, survival, proliferation, and differentiation. Oligodendrocytes are the myelin-forming cells in the central nervous system and play critical roles in the conduction of action potentials, supply of metabolic components for axons, and other functions. Emerging evidence suggests that both oligodendrocytes and oligodendrocyte precursor cells are vulnerable to cytokines released under pathological conditions. This review mainly summarizes the effects of cytokines on oligodendrocyte lineage cells in central nervous system diseases. A comprehensive understanding of the effects of cytokines on oligodendrocyte lineage cells contributes to our understanding of central nervous system diseases and offers insights into treatment strategies.

关键词： astrocyte central nervous system disease CXC chemokine cytokine interferonγ interleukin microglia oligodendrocyte oligodendrocyte precursor cell tumor necrosis factorα

Nickel-catalyzed arylcyanation of alkenes via cyano group translocation:access to 1,n-dinitriles or 4-amino nitriles

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Science China Chemistry 2024年第9期67卷 2975-2981页

作者： Xiaohong Li Shenfan Wang Xiangxiang fu Donghui Xing Zeyuan fu Yuanfu Deng Huanfeng Jiang Liangbin Huang State Key Laboratory of Pulp and Paper Engineering School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China

Herein,a nickel-catalyzed arylcyanation of unactivated alkenes via cyano group translocation with aryl boronic acids has been *** transformations provided a robust approach to constructing structurally diverse 1,n-dinitriles or 4-amino nitriles from easily prepared and commercially available starting *** cyano group translocation was achieved,involving the addition into the intramolecular C–N triple bond followed by the retro-Thorpe *** studies revealed that high temperature and CsHCO_(3) as the base were crucial for the cyano group translocation.

关键词： arylcyanation nickel catalysis cyano group translocation 1 n-dinitriles 4-amino nitriles

Trace formula of the integro-differential operator on a quantum graph

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 311-318页

作者： WEI Li-xiao YANG Chuan-fu School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094China.

In this paper we study the eigenvalue problem for integro-differential operators on a lasso *** trace formula of the operator is established by applying the residual technique in complex analysis.

关键词： integro-differential operators eigenvalue trace formula

Evaluation of 3D crustal seismic velocity models in southwest China:Model performance,limitation,and prospects

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Science China Earth Sciences 2024年第2期67卷 604-619页

作者： Xin WANG Ling CHEN Qi-fu CHEN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Southwest China is a tectonically and seismically active region,witnessing strong deformation due to the collision between the Indian and Eurasian *** the subsurface velocity structure of this region is thus important in understanding the tectonics and geodynamic processes of continental collision and in mitigating seismic *** studies have provided various 3D seismic velocity models in southwest ***,discrepancies exist among these models,and less effort has been made to quantify the reliability and accuracy of these existing velocity *** this study,we use regional 3D waveform simulation to evaluate the performance of various regional crustal 3D velocity models in reproducing observed *** particularly focus on two recent earthquake sequence in the region,the 2021 Yunnan Yangbi MS_(6.4) earthquake sequence and the 2022 Sichuan Luding MS_(6.8) earthquake *** tested 3D velocity models include the Southwest China Community Velocity model V1.0,the Unified Seismic Tomography Models for Continental China Lithosphere V2.0,the adjoint full waveform tomography model of the crustal and upper mantle beneath Eastern Tibetan Plateau,and the shallow seismic structure model beneath continental *** results show that the tested 3D velocity models generally capture well long-period(full-waveform tomography model shows a slighter better performance than the other models,especially for the body-waves,highlighting the advantages

关键词： Southwest China Seismic tomography models Shallow Structures Waveform simulation Model evaluation

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research International 2024年第4期31卷 838-848页

作者： fu-bin Gao fu-ming Wang Xiang Zhang Tian-yu Du Xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction