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Nerve protective effect of Baicalin on newborn HIBD rats

Asian Pacific Journal of Tropical Medicine 2014年第10期7卷 806-810页

作者： Xue-Mei liu yi Feng Ai-Min li Department of Pediatrics Yuhuang Ding Hospital Health Care Section Zhifu Hospital

Objetive:To investigate the nerve protective effect and mechanism of baicalin on newborn rats with hypoxic ischemic brain damage(HIBD).Methods:A total of 64 SD newborn rats were randomlu divided into control *** *** growth factor group and baicalin *** 16 in each *** carotid artery ligation method was adopted to establish the HIBD model except fou in control group,which was treatde with intraperitoneal injection of salin e10mL/kg for 3 *** oxygen recovery on hypoxia ischemia *** injectionof salin 10mL/kg was adopted in model group for 3 *** injection of nerve growth factor injection50μg/kg per day was adopted in nerve growth factor group for 3 d:intraperitoneal injection of radix scutellariae 16mg/kg per day was adopted in baicalin group for 3 d after *** rats of each group were sacrificed at Day 1,2,3,7 for microscopic observation of pathological morphological changes in brain tissus aften HE staining,S-P immunohistochemical method was used for observation of Fas and FasL expression in brain ***:Neat structure of cells was observed in control group;edema cells in disordered arrangement was observed in model group,with some cells necrosis and cavity change;tissue injury in nerve growth factor group and baicalin group was significantly lighter than that in model group;Fas and FasL expression in model group,nerve growth factor group and baicalin group were significantiy higher than that in control group at different time points(Plin group were significantly lower than that in model group at different time points(Plin group(P>0.05).Conclusions:Baicalin can reduce expression of Fas and FasL in HIBD rats,inhibit apoptosis of nerve cells,thus achieve the protective effect on HIBD rat nerves.

关键词： Newborn rats Hypoxic ischemic brain damage Baicalin Nerve protection

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Effect of Barrier Materials on Discharge Properties in Air at Low Pressure

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高电压技术 2007年第12期33卷 80-84页

作者： liMing li Cheng-rong ZHAN hua-mao XU Jin-bao ZHANG Xian-jun Beijing Key Laboratory of High Voltage ~ EMC School of Electric and Electronic Engineering North China Electric Power University Beijing 102206 China

Dielectric barrier discharge(DBD) is widely investigated in order to obtain uniform low-temperature *** studies have proved that some barrier materials,especially electrets,can improve the uniformity of *** is regarded as an available way to get atmospheric pressure glow discharge(APGD).In this paper,discharge forms with 4 different barrier materials(alumina,quartz,PTFE and PET) are investigated,and the transition of discharge form depending on the air pressure are recorded to estimate the influence of barrier materials on *** using electrets as barrier materials,homogeneous discharges can be obtained in a more wide pressure *** the same experimental conditions,discharges with electrets are more uniform or have larger uniform areas due to the storage and desorption of charges on the surface of *** electrons deposited in the surface layer can be released on next half cycle when the polarity of the applied voltage changes,and provide a number of seed electrons,which makes the discharge more *** capacitance and the permittivity of barrier materials have no effect on the discharge form directly.

关键词：放电特性低气压电子跃迁电介体表面电荷栅栏

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The molecular control of meiotic double-strand break (DSB) formation and its significance in human infertility

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Asian Journal of Andrology 2021年第6期23卷 555-561页

作者： Yang li Yu-Fan Wu Han-Wei Jiang Ranjha Khan Qi-Qi Han Furhan Iqbal Xiao-hua Jiang Qing-hua Shi Division of Reproduction and Genetics First Affiliated Hospital of USTCHefei National Laboratory for Physical Sciences at Microscalethe CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Basic Medical SciencesDivision of Life Sciences and MedicineCAS Center for Excellence in Molecular Cell ScienceCollaborative Innovation Center of Genetics and DevelopmentUniversity of Science and Technology of ChinaHefei 230027China Institute of Pure and Applied Biology Bahauddin Zakariya UniversityMultan 60000Pakistan

Meiosis is an essential step in gametogenesis which is the key process in sexually reproducing organisms as meiotic aberrations may result in infertility. In meiosis, programmed DNA double-strand break (DSB) formation is one of the fundamental processes that are essential for maintaining homolog interactions and correcting segregation of chromosomes. Although the number and distribution of meiotic DSBs are tightly regulated, still abnormalities in DSB formation are known to cause meiotic arrest and infertility. This review is a detailed account of molecular bases of meiotic DSB formation, its evolutionary conservation, and variations in different species. We further reviewed the mutations of DSB formation genes in association with human infertility and also proposed the future directions and strategies about the study of meiotic DSB formation.

关键词： DNA double-strand break(DSB) infertility meiosis mutation

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Synthesis and Herbicidal Activity of Novel Sulfonylureas Containing Thiadiazol Moiety

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Chemical Research in Chinese Universities 2008年第1期24卷 32-35页

作者： GUO Wan-cheng liU Xing-hai li Yong-hong WANG Su-hua li Zheng-ming Institute of Elemento-Organic Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Thirteen novel sulfonylureas containing thiadiazole moiety were synthesized in a two-step reaction. Their structures were determined using IR, ^1H NMR, HRFTMS, and elemental analysis. Herbicidal activities of these compounds were determined in the green house bio-assay. The results show that four compounds among them exhibit some activity toward four tested herbs.

关键词： Sulfonylurea Synthesis Herbicidal activity

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A comparison of the biological,geological events and environmental backgrounds between the Neoproterozoic-Cambrian and Permian-Triassic transitions

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Science China Earth Sciences 2010年第12期53卷 1873-1884页

作者： ShuZhong Shen MaoYan Zhu XiangDong Wang GuoXiang li ChangQun Cao hua Zhang Chinese Acad Sci State Key Lab Palaeobiol & Stratig Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the *** studies suggest that these two critical transitions showed certain comparability in major evolutionary *** other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T *** events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass *** coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and *** supercontinent Rodinia began to rift before the Snowball Earth *** contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to *** data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem *** is indicated by the disappearance of the whole Ediacaran biota at the N-C *** subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ***,the end-Permian mass extinction is manifested mainly by the extin

关键词： Neoproterozoic-Cambrian Permian-Triassic transition biological events geological events environmental background

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Solidification Structure of Continuous Casting Large Round Billets under Mold Electromagnetic Stirring

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Journal of Iron and Steel Research International 2016年第4期23卷 329-337页

作者： Tao SUN Feng YUE hua-jie WU Chun GUO ying li Zhong-cun MA Metallurgical Engineering Research Institute University of Science and Technology Beijing Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beiman Special Steel Co. Ltd.

The solidification structure of a continuous casting large round billet was analyzed by a cellular-automaton-finite-element coupling model using the ProCAST software. The actual and simulated solidification structures were compared under mold electromagnetic stirring （MEMS） conditions （current of 300 A and frequency of 3 Hz）. Thereafter, the solidification structures of the large round billet were investigated under different superheats, casting speeds, and secondary cooling intensities. Finally, the effect of the MEMS current on the solidification structures was obtained under fixed superheat, casting speed, secondary cooling intensity, and MEMS frequency. The model accurately simulated the actual solidification structures of any steel, regardless of its size and the parameters used in the continuous casting process. The ratio of the central equiaxed grain zone was found to increase with decreasing superheat, increasing casting speed, decreasing secondary cooling intensity, and increasing MEMS current. The grain size obviously decreased with decreasing superheat and increasing MEMS current but was less sensitive to the casting speed and secondary cooling intensity.

关键词： continuous casting large round billet solidification structure cellular-automaton-finite-element method mold electromagnetic stirring central equiaxed grain zone grain size

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Effect of phosphorus on the microstructure and mechanical properties of strip cast carbon steel

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 417-422页

作者： Na li Zhen-yu liu Guo-ping Zhou Xiang-hua liu Guo-dong Wang School of Materials and Metallurgy University of Science and Technology Liaoning Anshan 114051 China The State Key Laboratory of Rolling and Automation Northeast University Shenyang 110819 China

Carbon steel strips with different phosphorus and carbon contents were produced by using the twin roll strip casting process. Fine grains and dendrite structure were observed in high-P steels. Negative phosphorus segregation was found in strip cast high-P and high-C steels. For the steels with different carbon contents, phosphorus distribution in the thickness direction of the strip is obviously different. This is because solutes are redistributed in the melting pool and the phosphorus segregation rate is associated with the length of the mushy zone and the phosphorus solubility in different phases. Phosphorus as a solute in ferrite can lead to the higher hardness and strength with lower plastic propertyies.

关键词： phosphorus strip cast segregation mushy zone mechanical properties

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Some New Features of linear Theory for Describing Non-linear Diffusion

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Communications in Theoretical Physics 2009年第8期52卷 269-273页

作者： li Hang ZHU hua-ling JIA Ming-Yun WU Lao-Sheng College of Resources and Environment Southwest University Chongqing 400716 China Department of Environmental Sciences University of California Riverside CA 92507

The non-linear flux equation, the non-linear Fokker-Planck equation （or Smoluchowski equation）, and the non-linear Langiven equation are the basic equations for describing particle diffusion in non-ideal system subjected to time-dependent external fields. Nevertheless, the exact solution of those equations is still a challenge because of their inherent complexity of the non-linear mathematics. li et al. found that, based on the defined apparent variables, the nonlinear Fokker-Planck equation and the non-linear flux equation could be transformed to linear forms under the condition of strong friction limit or loeal equilibrium assumption. In this paper, some new features of the theory were found：（i） The linear flux equation for describing non-linear diffusion can be obtained from the irreversible thermodynamic theory; （ii） The linear non-steady state diffusion equation for describing non-linear diffusion of the non-steady state, which was described by the non-linear Fokker-Planek equation, can be derived more consistently from the microscopic molecular statistical theory; （iii） In the theory, the non-linear Langiven equation also bears a linear form; （iv） For some special cases, e.g. diffusion in a periodic total potential system, the local equilibrium assumption or the strong friction limit is not required in establishing the linear theory for describing non-linear diffusion, so the linear theory may be important in the study of Brown motor.

关键词： non-linear diffusion linear theory

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A new method used for reservoir production performance analysis

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Petroleum 2019年第1期5卷 30-34页

作者： Shuyong Hu yi Deng Yongkai li Ran Wang State Key Laboratory of Oil&Gas Reservoir Geology Exploitation Engineering Southwest Petroleum UniversityChengduPeople's Republic of China Sulige Project Management Department CCDCOrdosPeople's Republic of China

Water flooding type-curves,recently receiving increasing attentions,play an essential role in evaluation of OOIP and prediction of future *** study proposed a method modified form Weibull model and water flooding type-curves to analyze the reservoir production performance,including predication of oil production and water injection *** results indicate that the method can estimate and provide solutions for oil production,water injection rate and injection-production ratio with a well accuracy.A case study is conducted to demonstrate the applicability and accuracy of model by field *** matching results illustrate a good accordance between calculated values and field data.

关键词： Weibull model Water flooding type-curves Oil production Water injection rate Injection-production ratio

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Design of H_∞ robust fault detection filter for nonlinear time-delay systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1733-1741页

作者： BAI Lei-shi HE li-ming TIAN Zuo-hua SHI Song-jiao Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

In this paper, the robust fault detection filter (RFDF) design problems are studied for nonlinear time-delay systems with unknown inputs. First, a reference residual model is introduced to formulate the RFDF design problem as an H∞ model-matching problem. Then appropriate input/output selection matrices are introduced to extend a performance index to the time-delay systems in time domain. The reference residual model designed according to the performance index is an optimal residual generator, which takes into account the robustness against disturbances and sensitivity to faults simultaneously. Applying robust H∞ optimization control technique, the existence conditions of the RFDF for nonlinear time-delay systems with unknown inputs are presented in terms of linear matrix inequality (LMI) formulation, independently of time delay. An illustrative design example is used to demonstrate the validity and applicability of the proposed approach.

关键词： Nonlinear time-delay systems Robust fault detection filter iRFDF H∞ optimization linear matrix inequality (LMI)

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