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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

适用于大规模分布式交互仿真的应用层组播研究

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系统仿真学报 2004年第6期16卷 1271-1274页

作者：李春洪叶保留顾铁成陈道蓄南京大学计算机软件新技术国家重点实验室

组播技术具有良好的伸缩性和高效的数据传输效率,是大规模分布式交互仿真应用中理想的通信机制。早期的组播技术研究侧重于从IP层提供组播通信支持,但IP组播的实施涉及到网络基础设施的调整,且大规模应用还受到一些技术因素的阻碍。应... 详细信息

组播技术具有良好的伸缩性和高效的数据传输效率,是大规模分布式交互仿真应用中理想的通信机制。早期的组播技术研究侧重于从IP层提供组播通信支持,但IP组播的实施涉及到网络基础设施的调整,且大规模应用还受到一些技术因素的阻碍。应用层组播(ALM)将组成员组织成覆盖网络为数据传输提供服务,组播功能完全由终端系统在应用层实现,从而易于大规模部署和实现。本文介绍了应用层组播模型的机理和构造协议,分析了大规模DIS系统中通信需求的特点,探讨在大规模DIS中实施应用层组播的一些相关问题。

关键词： IP组播分布式交互仿真应用层组播覆盖网络

Fabrication and characterization of mussel-inspired layer-by-layer assembled CL-20-based energetic films via micro-jet printing

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Defence Technology（防务技术） 2022年第10期18卷 1748-1759页

作者： chun-yan Li Sheng Kong Dong-jie Liao Chong-wei An bao-yun ye Jing-yu Wang School of Environment and Safety Engineering North University of ChinaTaiyuan030051ShanxiChina Shanxi Engineering Technology Research Center for Ultrafine Powder North University of ChinaTaiyuan030051ShanxiChina Taiyuan Institute of Technology Taiyuan030008ShanxiChina

Three-dimensional(3D)micro-jet printing is a droplet deposition technique based on liquid-phase *** improve the deposition density and performance of energetic films with micro/nanoscale on an energetic chip,polydopamine(PDA)was utilized as a linker bridge to induce the in-situ self-assembly of CL-20-based energetic film via 3D micro-jet *** self-assembly was extensively characterized by confocal laser scanning microscopy(CLSM),SEM,power-XRD,XPS,and *** performance of the self-assembled film was verified by the mechanical properties and detonation properties,and a possible self-assembly mechanism in the layer-by-layer micro-jet printing process was *** results indicated PDA-induced self-assembly enhanced the physical entanglement between the binders and energetic crystal,reduced the porosity from 15.87%to 11.28%,and improved the elastic modulus and the detonation performance of the CL-20-based energetic *** work proposes a novel and promising energetic film design and fabrication strategy to enhance the interaction between the energetic composite layers in the micro-jet printing process.

关键词： CL-20-Based energetic film Micro-jet printing Polydopamine Self-assembly

A Performance Study of the CCD Cameras of the Joint Laboratory of Optical Astronomy

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 397-410页

作者： bao-AnYao chun-ShengZhang QingLin ShanghaiAstronomicalObservatory ChineseAcademyofSciencesShanghai200030 PurpleMountainObservatory ChineseAcademyofSciencesNanjing210008

A performance study of several CCD cameras of the Chinese Joint Laboratory of Optical Astronomy (CJLOA) is presented. The main results are: 1) We propose a modified classical method to analyse the linearity of CCD cameras. This method is more sensitive and accurate as well as more intuitive, especially in measuring around the 0.1%-0.2% range of nonlinearity. 2) To illustrate the advantage of the method, the linearity performance of the CCD cameras at CJLOA has been measured and analysed. 3) For the CCD systems tested, there is no unique formula to represent the correlation over the entire CCD frame between the deviation from linearity and the pixel value, i.e., different pixel has different correction even though their pixel values are the same. 4) For the BFOSC (bao Faint Object Spectrograph Camera) Loral CCD camera and the Tek CCD camera at the 1.56-m reflector, blooming (bleeding) happens long before saturation, and we suspect whether it could have resulted from the charge transfer efficiency (CTE) not being high enough.

关键词： instrumentation: detectors - telescopes

Eurasian Snow Conditions and Summer Monsoon Rainfall over South and Southeast Asia: Assessment and Comparison

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Advances in Atmospheric Sciences 2005年第6期22卷 877-888页

作者： Hengchun ye Zhenhao bao Department of Geography and Urban Analysis California State University Los Angeles USA Department of Earth and Atmospheric Science York University 4700 Keele Street Canada University of Toronto Toronto Ontario Canada M3J1P3

This study reveals the complex nature of the connection between Eurasian snow and the following summer season＇s monsoon rainfall by using four different indicators of snow conditions and correlating each of them to summer monsoon rainfall. Using 46 years of historical records of mean winter snow depth, maximum snow depth, and snow starting dates, and 27 years of snow area coverage from remote sensing observations over Eurasia, the authors found diverse correlation patterns between snow conditions and the following warm season＇s rainfall over South and Southeast Asia. Some of the results contradict the well-known inverse relationships between snow and the summer monsoon. This study provides an easy comparison of results in that it shows the connections between Eurasian snow and monsoon rainfall by using different Eurasian snow indicators based on the best available historical records without discrimination of regional variations in snow conditions.

关键词： Eurasian snow Southeast Asian monsoon precipitation snowcover snow depth snow dates

Analysis of sliding electric contact characteristics in augmented railgun based on the combination of contact resistance and sliding friction coefficient

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Defence Technology（防务技术） 2020年第4期16卷 747-752页

作者： chun-yan Zhu bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyChina

The contact resistance between the armature and rails is an important indicator of the contact characteristics in electromagnetic *** the contact resistance depends not only on the contact state but also on the contact stress and temperature,there are some limitations in analyzing the contact characteristics using only the contact *** this paper,the contact characteristics of the augmented railgun are analyzed by the combination of contact resistance and sliding friction ***,the theoretical calculation model of the contact resistance and friction coefficient of the augmented electromagnetic railgun is *** the contact resistance and friction coefficient are calculated by the measured values of the muzzle voltage,rail current and armature ***,the contact characteristics are analyzed according to the features of the waveforms of the contact resistance and the friction coefficient,and the analysis conclusions are verified by experimental rail *** results showed that:the aluminum melt film gradually formed on the contact surface reduces the contact resistance and the friction coefficient;the wear and erosion of the armature cause deterioration of the contact state;after the transition,the reliability of the sliding contact between the armature and rails decreases,resulting in an increase in contact resistance.

关键词： Augmented railgun Contact resistance Friction coefficient Contact characteristics

Cohomology structure for a Poisson algebra:Ⅱ

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Science China Mathematics 2021年第5期64卷 903-920页

作者： Yan-Hong bao Yu ye School of Mathematical Sciences Anhui UniversityHefei 230601China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China Wu Wen-Tsun Key Laboratory of Mathematics USTCChinese Academy of SciencesHefei 230026China

For a Poisson algebra,we prove that the Poisson cohomology theory introduced by Flato et al.(1995)is given by a certain derived *** show that the(generalized)deformation quantization is equivalent to the formal deformation for Poisson algebras under certain mild *** we construct a long exact sequence,and use it to calculate the Poisson cohomology groups via the Yoneda-extension groups of certain quasi-Poisson modules and the Lie algebra cohomology groups.

关键词： Poisson algebra Poisson cohomology formal deformation deformation quantization

Reactive oxygen species metabolism during the cadmium hyperaccumulation of a new hyperaccumulator Sedum alfredii (Crassulaceae)

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Journal of Environmental Sciences 2007年第11期19卷 1311-1317页

作者： ZHANG Zhong-chun QIU bao-sheng College of Life Sciences Huazhong Normal University Wuhan 430079 China

Sedum alfredii Hance, a newly discovered hyperaccumulator, could serve as a good material for phytoremediation of Cd polluted sites. Malondialdehyde （MDA）, reactive oxygen species （ROS） and antioxidases （catalase （CAT）; superoxide dismutase （SOD）; peroxidase （POD）） in the leaf were determined when S. alfredii was treated for 15 d with various CdC12 concentrations ranging from 0 to 800 μmol/L. The results showed that the production rate of 2＇,7＇-dichlorofluorescein （DCF）, which is an indicator of ROS level, reached up to the maximum at 400 μmol/L CdCl2 and then declined with the increase of CdCl2 concentration, while MDA accumulation tended to increase. CAT activity was significantly inhibited at all tested CdCl2 concentrations and SOD activity was sharply suppressed at 800 μmol/L CdCl2. However, the enhancement of POD activity was observed when CdCl2 concentration was higher than 400 μmol/L. In addition, its activity increased when treated with 600 μmol/L CdCl2 for more than 5 d. When sodium benzoate, a free radical scavenger, was added, S. alfredii was a little more sensitive to Cd toxicity than that exposed to Cd alone, and the Cd accumulation tended to decline with the increase of sodium benzoate concentration. It came to the conclusions that POD played an important role during Cd hyperaccumulation, and the accumulation of ROS induced by Cd treatment might be involved in Cd hyperaccumulation.

关键词： cadmium hyperaccumulation reactive oxygen species Sedum alfredii

Exfoliation of poly(ethylene glycol)-intercalated graphite oxide composite in water without sonication

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 840-845页

作者： Yang Hu chun-bao Sun Jue Kou School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

A novel method for exfoliating graphite oxide(GrO)was implemented through the mass water absorption of a GrO–poly(ethylene glycol)(GrO–PEG)*** GrO–PEG composite was prepared by intercalating PEG into the lamellae of GrO,and the variation of the basal spacing was measured by X-ray diffraction *** yield of graphene was measured with an ultraviolet–visible spectrophotometer,and the properties of graphene oxide(GO)were characterized by atomic force microscopy,transmission electron microscopy(TEM),Raman spectrometry,and Fourier transform infrared *** intercalation time was found to improve the yield of GO,whereas increasing the PEG molecular weight had the opposite *** GO sheets produced from the intercalation–absorption–exfoliation process were found to be a four-layer *** and Raman analyses indicate that the graphitized structure and oxygen groups of GO were preserved during the exfoliation *** importantly,the results show that good-quality GO could be prepared via a mild method involving water absorption of a GrO–PEG composite.

关键词： graphene oxide poly(ethylene glycol) intercalation exfoliation