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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao chen chen Shuo wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

The ratio of MMP-2 to TIMP-2 in hilar cholangiocarcinoma:a semi-quantitative study

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Hepatobiliary & Pancreatic Diseases International 2004年第4期3卷 599-602页

作者： Mei Xiao, Nin-Xing Zhou,Zhi-Qiang Huang,Ya-Li Lu, Ling-hong chen, Dian-Jun wang and Wei-Lin Chang Beijing, China Department of Hepatobiliary Surgery, General Air- force of Hospital, Beijing 100036, China and General Hospital of People’ s Liberation Army, Beijing 100853 , China Department of Hepatobiliary Surgery of General Airforce of Hospital Beijing 100036 China. fengweiairforce@***

BACKGROUND: Hilar cholangiocarcinoma is associated with low resectability and poor survival. The aim of this study was to evaluate the roles of matrix metalloproteinases- 2 (MMP-2 ) and its tissue inhibitor of metalloproteinase-2 (TIMP-2) in tumor invasion or as a prognostic factor in patients with human hilar cholangiocarcinoma. METHODS: The expressions of MMP-2 and TIMP-2 were investigated in patients. Paraffinized tissue sections ob- tained from 50 patients with human hilar cholangiocarcino- ma were analysed. The expressions of MMP-2 and TIMP-2 were examined immunohistochemically. Image analysis with image-pro plus analysis software was used to semi- quantitatively determine the ratio of MMP-2 to TIMP-2. RESULTS: The expression levels of MMP-2 and TIMP-2 were strongly associated with tumor hepatic invasion in pa- tients with hilar cholangiocarcinoma. Significant diffe- rences in the ratio of MMP-2 to TIMP-2 between some pathologic factors were observed in patients with hilar cholangiocarcinoma. CONCLUSIONS: MMP-2 plays an essential role in tumor invasion and metastasis,while TIMP-2 is shown to strongly inhibit cancer invasion and metastasis. The ratio of MMP-2 to TIMP-2 may be a prognostic indicator for patients with hilar cholangiocarcinoma.

关键词： hilar cholangiocarcinoma matrix metalloproteinase-2 tissue inhibitor of metalloproteinase-2 immunohistochemical staining tumor invasion prognostic factor

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang Yanlin Fu Peiyan Long Xiao Gao Zhengwei wang Zhizhong Guan Xiaolan Qi Wei hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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Science China Technological Sciences 2025年

作者： Kuangda chen Huan ZHAO Jiexin ZHANG Mei FENG Yiwei wang Jinliang wang Han DING State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin University School of Medical Equipment Science and Engineering Huazhong University of Science and Technology

Narrow space manipulations are crucial for equipment maintenance, as they eliminate the need for disassembly, thus reducing costs and increasing efficiency. Cable-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces, thanks to their interaction compliance and distal dexterity. However, their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation failure. To address this challenge, this paper proposes a novel type of rigid-flexible coupling robot, which increases the stiffness of the robot while ensuring the reachability within a narrow space. To achieve high-accuracy location in a narrow space, kinematic and control methods are proposed. Specifically,the robot forward kinematics are uniformly represented, and the closed-form inverse kinematics solution is derived. Furthermore, in cases where the robot?s structure fails to align with Pieper?s solution, a two-stage search strategy is utilized to solve the inverse kinematics, resulting in a high success rate of 99.1%. Based on the proposed kinematics, a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow spaces. The practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

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Dual modulation of homogeneous nanomaterialization and electrochemical activation enhancing zinc ion storage

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Science China Chemistry 2025年第1期68卷 385-393页

作者： Jianwei wang Huan wang Kangning wang Wenhui wang Wenlin Zhang Yanzhong Zhen School of Chemistry & Chemical Engineering Yan'an University

Vanadium-based electrode materials are widely investigated,but the low specific capacity and slow electrochemical kinetics in aqueous zinc-ion batteries still limit their commercial ***,the VS2/Ca V4O9material with the morphology of nanoflower was synthesized by a one-step hydrothermal *** to the blocky structure of pure VS2material,the VS2/Ca V4O9material is composed of thinner homogeneous *** open structures could provide abundant electrochemical active sites and ion transport channels,and then promote the electrochemical reaction *** addition,they can also buffer the bulk strain during the reaction *** improve the utilization of vanadium elements,an in-situ electrochemical activation strategy is used to explore the storage performance of the VS2/Ca V4O9material,the different activation voltage range of 0.4–1.6 and 0.4–1.4 V are selected,*** with the longer activation plateau of activated-VS2,the VS2/Ca V4O9cathode could quickly reach the activation state in the range of 1.4–1.6 V and cause the release of additional Zn storage sites *** VS2/Ca V4O9cathode delivers a higher power density of 37,000 W kg-1and a significant energy density of 423 Wh *** the high current density of 15 A g-1,the VS2/Ca V4O9cathode still has a discharge capacity of 183.9m Ah g-1after 5,000 cycles,and the capacity decay rate per cycle is only 0.0042%.Continuous cyclic voltammetry （CV） curves,electrochemical impedance spectroscopy （EIS） measurements,density functional theory （DFT） calculation and galvanostatic intermittent titration technique （GITT） measurements demonstrate that the VS2/Ca V4O9cathode has a faster ion diffusion/charge transfer ***,the assembled flexible device has an excellent mechanical stability.

关键词： dual modulation homogeneous nanomaterialization electrochemical activation zinc ion storage

输卵管妊娠种植部位与非种植部位组织学的比较

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生殖与避孕 2009年第1期29卷 48-50页

作者：许多朱伟杰王晨虹南方医科大学附属深圳市妇幼保健院产科深圳518028 暨南大学生殖免疫研究中心广州510632

目的:比较观察输卵管妊娠种植部位与非种植部位的组织学改变,为准确取材提供参考。方法:50例标本取自妊娠囊尚未破裂的输卵管妊娠患者,每例的取材在离妊娠囊5mm以内的部位作为种植部位取材,10mm以外作为非种植部位取材。采用HE染色法观... 详细信息

目的:比较观察输卵管妊娠种植部位与非种植部位的组织学改变,为准确取材提供参考。方法:50例标本取自妊娠囊尚未破裂的输卵管妊娠患者,每例的取材在离妊娠囊5mm以内的部位作为种植部位取材,10mm以外作为非种植部位取材。采用HE染色法观察输卵管妊娠种植部位和非种植部位输卵管上皮的组织学改变。结果:50例人输卵管妊娠种植部位的输卵管壁内黏膜均可见成片的滋养细胞,其中10例种植部位的输卵管黏膜见蜕膜改变,呈不规则的片状。非种植部位的输卵管黏膜多为慢性非特异性炎症表现,无滋养细胞浸润。结论:输卵管妊娠种植部位存在滋养细胞。在上述位置取材并结合滋养细胞有无,易于确定输卵管妊娠种植部位与非种植部位。

关键词：输卵管异位妊娠滋养细胞

Exit options sustain altruistic punishment and decrease the second-order free-riders, but it is not a panacea

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Science China(Information Sciences) 2025年第1期68卷 278-291页

作者： chen SHEN Zhao SONG Lei SHI Jun TANIMOTO Zhen wang Faculty of Engineering Sciences Kyushu University School of Statistics and Mathematics Yunnan University of Finance and Economics School of Computing Engineering and Digital Technologies Teesside University School of Artificial Intelligence OPtics and Electro Nics (iOPEN) Northwestern Polytechnical University

Why do humans punish free riders at their own expense? This behavior represents an evolutionary puzzle in human societies. This study explores the role of exit strategies in fostering altruistic punishment within evolutionary game theory. We extend the traditional prisoner's dilemma model by incorporating exiters, players who opt out for a small payoff while nullifying their opponent's payoff, and altruistic punishers who cooperate and punish non-cooperators. Our findings indicate that in well-mixed populations, exiters destabilize defection but do not promote altruistic punishment. In social networks, however,exiters enable altruistic punishment via cyclic dominance among altruistic punishers, defectors, and exiters. Notably, this cyclic dominance is sensitive to exit payoffs; adjustments can lead to cyclic dominance of non-punishing cooperators, defectors, and exiters, or to a bi-stable state between these two types of cyclic dominance. These results highlight the nuanced impact of exiters on altruistic punishment, emphasizing the need for careful incentivization of exit behavior. While exiters can support altruistic punishment in networked populations, their effectiveness is not a panacea and is highly sensitive to exit payoffs, indicating limits to the voluntary participation mechanism.

关键词： evolutionary game theory altruistic punishment coexistence cyclic dominance bi-stable

Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun Ren Jiang Yu Jing wang ZuZheng chen XiaoMan Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

Federated local causal structure learning

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Science China(Information Sciences) 2025年

作者： Kui YU chen RONG Hao wang Fuyuan CAO Jiye LIANG School of Computer and Information Hefei University of Technology School of Computer and Information Technology Shanxi University

Local causal structure learning (LCS) efficiently identifies a set of direct neighbors of a specified variable from observational data. Additionally, it distinguishes direct causes and direct effects of this variable without learning the entire causal structure. While many LCS algorithms have been proposed, they do not consider the data privacy-preserving problem,which has attracted extensive attention from academia and industry. To address this issue, we propose a federated local causal structure learning (FedLCS) algorithm to learn local causal structures in privacy-preserving data in a federated ***, FedLCS introduces a layer-wise federated local skeleton learning algorithm to construct the local skeleton. Based on this skeleton, it introduces a federated local skeleton orientation algorithm and an extension-and-backtracking orientation algorithm to orient the edges. Finally, FedLCS uses a federated local extension-and-backtracking orientation algorithm to orient the remaining edges. Extensive experiments on benchmark, synthetic, and real datasets demonstrate that FedLCS can learn the local causal structure of a given variable in a federated setting.

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Inhibiting SHP2 reduces glycolysis, promotes microglial M1 polarization, and alleviates secondary inflammation following spinal cord injury in a mouse model

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Neural Regeneration Research 2025年第3期20卷 858-872页

作者： Xintian Ding Chun chen Heng Zhao Bin Dai Lei Ye Tao Song Shuai Huang Jia wang Tao You Department of Orthopedics The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Orthopedics Provincial Hospital Affiliated to Anhui Medical UniversityHefeiAnhui ProvinceChina

Reducing the secondary inflammatory response, which is partly mediated by microglia, is a key focus in the treatment of spinal cord injury. Src homology 2-containing protein tyrosine phosphatase 2(SHP2), encoded by PTPN11, is widely expressed in the human body and plays a role in inflammation through various mechanisms. Therefore, SHP2 is considered a potential target for the treatment of inflammation-related diseases. However, its role in secondary inflammation after spinal cord injury remains unclear. In this study, SHP2 was found to be abundantly expressed in microglia at the site of spinal cord injury. Inhibition of SHP2 expression using siRNA and SHP2 inhibitors attenuated the microglial inflammatory response in an in vitro lipopolysaccharide-induced model of inflammation. Notably, after treatment with SHP2 inhibitors, mice with spinal cord injury exhibited significantly improved hind limb locomotor function and reduced residual urine volume in the bladder. Subsequent in vitro experiments showed that, in microglia stimulated with lipopolysaccharide, inhibiting SHP2 expression promoted M2 polarization and inhibited M1 polarization. Finally, a co-culture experiment was conducted to assess the effect of microglia treated with SHP2 inhibitors on neuronal cells. The results demonstrated that inflammatory factors produced by microglia promoted neuronal apoptosis, while inhibiting SHP2 expression mitigated these effects. Collectively, our findings suggest that SHP2 enhances secondary inflammation and neuronal damage subsequent to spinal cord injury by modulating microglial phenotype. Therefore, inhibiting SHP2 alleviates the inflammatory response in mice with spinal cord injury and promotes functional recovery postinjury.

关键词： apoptosis glycolysis inflammatory response microglia neurons polarization spinal cord injury Src homology 2-containing protein tyrosine phosphatase 2