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Analgesic and anti-inflammatory activities and mechanisms of 70% ethanol extract of Zygophyllum macropodum in animals

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Chinese Herbal Medicines 2018年第1期10卷 59-65页

作者： xiao-rong yang xiang-feng zhang xue-mei zhang hong-yan gao school of biology and geography science yili normal universityyining 835000china university and college key lab of natural product chemistry and application in xinjiang resources and ecology instituteyili normal universityyining 835000china school of chemistry and environment science yili normal universityyining 835000china

Objective： To screen the preliminary phytochemical components, to investigate the acute oral toxicity, the analgesic and anti-inflammatory effects, and to analyze inflammatory factors on mice or rats of 70% ethanol extract of Zygopgyllurn macropodum aerial parts （ZME）. Methods： Preliminary phytochemical screening was carried out by color reaction. Acute oral toxicity was investigated by body weight, relative organ weight and other toxic signs. Acetic acid induced writhing and hot plate test were used to determine analgesic effect. Acetic acid induced vascular permeability and carrageenan induced paw edema were used to confirm anti-inflammation. Protein in pleural effu- sion, prostaglandin E2 （PGE2） and tumor necrosis factor alpha （TNF-a） in serum of pleuritic rats induced by carrageenan were analyzed to explore the action mechanisms. The test groups received ZME with 100, 300, 600 mg/kg, the positive control with aspirin （ASP） 200 mg/kg for mice, and ZME with 70, 210, 420 mg/kg and ASP 150 mg/kg for rats orally. The control （C） or negative control （NC） groups received 2% Tween 80 of 10 mL/kg orally. Results： ZME contain flavonoids, saponins, phenols and tannins, steroids, terpenoids, fats and oils, glycosides, carbohydrates, and reducing sugar, but no alkaloids. The lethal dose 50% （LD50） of ZME was greater than 2000 mg/kg and no toxic or deleterious effects and death during 14 d. Oral administration 300 and 600 mgJkg of ZME produced analgesic and anti-inflammatory effects significantly （P 〈 0.05 or P 〈 0.001） vs NC. It can reduce the writhing number, prolong the heat resisting time, suppress the permeability of the capillary wall increasing, mitigate the paw edema, reduce the content of protein in pleural effusion, and reduce PGE2 and TNF-α in blood. Conclusions： ZME possessed analgesic and anti-inflammatory activities which related to inhibit the production of protein, PGE2 and TNF-α. The LD50 of ZME treated orally to mice was greater than 2000 mg/kg.

关键词： effects protein Prostaglandin E2 tumor necrosis factor alpha Zygophyllum macropodum

A review on plasmonic enhancement of activity and selectivity in electrocatalytic CO_(2)reduction

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Frontiers in Energy 2024年第4期18卷 399-417页

作者： Jing xue Zhenlin CHEN Yuchao zhang Jincai ZHAO Key Laboratory of Photochemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Utilizing plasmonic effects to assist electrochemical reactions exhibits a huge potential in tuning the reaction activities and product selectivity,which is most appealing especially in chemical reactions with multiple products,such as CO_(2)reduction reaction(CO_(2)RR).However,a comprehensive review of the development and the underlying mechanisms in plasmon-assisted electrocatalytic CO_(2)RR remains few and far ***,the fundamentals of localized surface plasmonic resonance(LSPR)excitation and the properties of typical plasmonic metals(including Au,Ag,and Cu)are ***,the potential mechanisms of plasmonic effects(such as hot carrier effects and photothermal effects)on the reaction performance in the field of plasmon-assisted electrocatalytic CO_(2)RR are summarized,which provides directions for the future development of this *** is concluded that plasmonic catalysts exhibit potential capabilities in enhancing CO_(2)RR while more in situ techniques are essential to further clarify the inner mechanisms.

关键词： localized surface plasmonic resonance(LSPR)effect plasmonic metals CO_(2)reduction reaction(CO_(2)RR) hot carrier effect photothermal effect

Improving strength-ductility synchronously of Electron beam welded Ti600/Ti2AlNb joint through isothermal forging

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Progress in Natural Science:Materials International 2024年第3期34卷 532-539页

作者： Yongqiang zhang Xiangyi xue Guoming Zheng Jingli zhang Huiming Li Shewei Xin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Qin Ti Intelligent Manufacturing Technologies Co.Ltd. Northwest Institute for Nonferrous Metal Research Xi'an University of Science and Technology Avic Xi'an Aircraft Industry Group Company Ltd.

Different alloys can be flexibly combined to meet the performance needs of different parts of the compressor disc by welding process. However, achieving a good combination of dissimilar alloys with different mechanical properties has always been a research difficulty. In this work, a Ti600/Ti2AlNb joint was fabricated through electron beam welding and an isothermal forging was used to optimized its microstructure and mechanical performance. The isothermal forging process increases the ultimate tensile strength（UST） and yield strength（YS）of the Ti600/Ti2AlNb joint by ～18 %, while ～2.5 times the ductility. It is indicated that before forging, the Ti600/Ti2AlNb joint exhibits a much lower strength than that of Ti600 matrix, whereas the opposite is true after isothermal forging. The isothermal forging broken the coarse columnar grains of Ti600/Ti2AlNb joint and render to an equiaxed B2 structure in which the acicular α2and O phase are precipitated, resulting a synchronous enhancement of strength and ductility. This work may pave an effective routine for improving the comprehensive mechanical properties of dissimilar metal welding joint.

关键词： Electron beam welding Isothermal forging Mechanical performance Ti600/Ti2AlNb joint

Insufficient Physical Activity among Students Aged 6-17 Years in China,2016-2017

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Biomedical and Environmental Sciences 2024年第5期37卷 531-536页

作者： xue Tao Tao GAO Xing Xing WANG Li Min zhang Xiao ZHAO Zhen Ping LI Chun NYASHA Grace Mudoti LIU Chen Yi zhang mei Division of Chronic Disease and Risk Factor Surveillance National Center for Chronic and Non-communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 100050China International Education School China Medical UniversityShenyang 110122LiaoningChina

Regular physical activity of sufficient duration and intensity can provide health benefits such as improved physical fitness,which promotes bone health,prevents hypertension,improves mental health,and reduces adiposit... 详细信息

关键词： hypertension Regular benefits

A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

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Journal of Arid Land 2024年第9期16卷 1163-1182页

作者： GUO Bing XU mei zhang Rui LUO Wei School of Civil Engineering and Geomatics Shandong University of TechnologyZibo 255000China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China North China Institute of Aerospace Engineering Langfang 065000China

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade ***,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be ***,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving *** results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River *** 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability *** intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi *** 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of *** gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the *** dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional *** above results could provide decision support for the ecological protection and restoration of the Y

关键词： ecological vulnerability spatio-temporal pattern gravity center migration trajectory interaction factors geodetector green index q-value

Facile synthesis of composite polyferric magnesium-silicate-sulfate coagulant with enhanced performance in water and wastewater

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 574-584页

作者： Xiangtao Huo Rongxia Chai Lizheng Gou mei zhang Min Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The coagulation process is a widely applied technology in water and wastewater *** composite polyferric mag-nesium-silicate-sulfate(PFMS)coagulants were synthesized using Na_(2)SiO_(3)·9H_(2)O,Fe_(2)(SO_(4))_(3),and MgSO_(4) as raw materials in this *** effects of aging time,Fe:Si:Mg,and OH:M molar ratios(M represents the metal ions)on the coagulation performance of the as-pre-pared PFMS were systematically investigated to obtain optimum *** results showed that PFMS coagulant exhibited good co-agulation properties in the treatment of simulated humic acid-kaolin surface water and reactive dye *** the molar ratio was controlled at Fe:Si:Mg=2:2:1 and OH:M=0.32,the obtained PFMS presented excellent stability and a high coagulation *** removal efficiency of ultraviolet UV254 was 99.81%,and the residual turbidity of the surface water reached 0.56 NTU at a dosage of 30 mg·L^(-1).After standing the coagulant for 120 d in the laboratory,the removal efficiency of UV254 and residual turbidity of the surface wa-ter were 88.12%and 0.68 NTU,respectively,which accord with the surface water treatment *** addition,the coagulation performance in the treatment of reactive dye wastewater was greatly improved by combining the advantages of magnesium and iron *** with polyferric silicate-sulfate(PFS)and polymagnesium silicate-sulfate(PMS),the PFMS coagulant played a better decolor-ization role within the pH range of 7-13.

关键词： polyferric-magnesium-silicate-sulfate composite coagulants water and wastewater excellent stability high coagulation ef-ficiency decolorization

Big Data Application Simulation Platform Design for Onboard Distributed Processing of LEO Mega-Constellation Networks

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China Communications 2024年第7期21卷 334-345页

作者： zhang Zhikai Gu Shushi zhang Qinyu xue Jiayin School of Electronics and Information Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Shenzhen 518055China Broadband Communications Research Department Peng Cheng LaboratoryShenzhen 518000China

Due to the restricted satellite payloads in LEO mega-constellation networks(LMCNs),remote sensing image analysis,online learning and other big data services desirably need onboard distributed processing(OBDP).In existing technologies,the efficiency of big data applications(BDAs)in distributed systems hinges on the stable-state and low-latency links between worker ***,LMCNs with high-dynamic nodes and long-distance links can not provide the above conditions,which makes the performance of OBDP hard to be intuitively *** bridge this gap,a multidimensional simulation platform is indispensable that can simulate the network environment of LMCNs and put BDAs in it for performance *** STK's APIs and parallel computing framework,we achieve real-time simulation for thousands of satellite nodes,which are mapped as application nodes through software defined network(SDN)and container *** elaborate the architecture and mechanism of the simulation platform,and take the Starlink and Hadoop as realistic examples for *** results indicate that LMCNs have dynamic end-to-end latency which fluctuates periodically with the constellation *** to ground data center networks(GDCNs),LMCNs deteriorate the computing and storage job throughput,which can be alleviated by the utilization of erasure codes and data flow scheduling of worker nodes.

关键词： big data application Hadoop LEO mega-constellation multidimensional simulation onboard distributed processing

Perspective for OER electrocatalysts:Lattice engineering of clay-like frameworks with near-surface cluster active sites

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Science China(Technological Sciences) 2024年第1期67卷 330-334页

作者： zhang DanTong QIAN BinBin xue DongFeng Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Near-surface cluster active centers(NSCAC)are pivotal functional units in the catalysis of oxygen evolution reaction(OER),which exceeds the limitations imposed by the diverse coordination environments experienced in atomic and molecular active centers,thereby serving as an exceptional medium for exploring the dynamic catalytic processes of metal active sites[1,2].In the OER,the NSCAC primarily consist of the catalytic site and the first neighboring coordinating *** investigation of NSCAC surpasses the exclusive reliance on the electron state regulation mechanism at the atomic level.

关键词： cluster centers exceptional

A survey on the network models applied in the industrial network optimization

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Science China(Information Sciences) 2024年第2期67卷 85-103页

作者： Chao DONG Xiaoxiong XIONG Qiulin xue Zhengzhen zhang Kai NIU Ping zhang Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Smart City College Beijing Union University

Network architecture design is critical for optimizing industrial networks. Network architectures can be classified into small-scale networks and large-scale networks based on scale. Graph theory is an efficient mathematical tool for network topology modeling. For small-scale networks, their structure often has regular topology. For large-scale ones, the current body of work mainly focuses on random characteristics of network nodes and edges. Recently, widely used models include random networks, small-world networks,and scale-free networks. In this study, starting from the scale of the network, network modeling methods based on graph theory as well as their industrial applications, are summarized and analyzed. Moreover, a novel network performance metric, called system entropy, is proposed. From the perspective of mathematical properties, an analysis of its non-negativity and concavity is performed. The advantage of system entropy is that it can cover the existing regular networks, random networks, small-world networks, and scale-free networks, and has strong generality. The simulation results reveal that this proposed metric can achieve the comparison of various industrial networks under different models.

关键词： industrial network small-scale network large-scale network graph theory system entropy