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A possible Younger Dryas-type event during Asian monsoonal Termination 3

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Science China Earth Sciences 2006年第9期49卷 982-990页

作者： CHEN Shitao1, WANG Yongjin1, KONG Xinggong1, LIU Dianbing1, CHENG Hai2.& R.L. Edwards2.1. college of Geography Science, Nanjing Normal university, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 2.0097, China 2. {2. of Geology and Geophysics, university of Minnesota, Minneapolis MN55455, USA 1. college of Geography Science Nanjing Normal University Jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing 210097 China 2. department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

Seven U-Th dates, 560 δ 18O data and microscopic sequences were measured for sta- lagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the de- cadal-resolution stalagmite δ 18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ 18O records from Nanjing, Jiangsu Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 30-year-resolution stalagmite δ 18O record from Yongxing Cave (1400 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3 at about 2.5±5 kaBP. Based on 3 U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3 from the Yongxing δ 18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ 18O record, generally agrees with the pattern of the YD event well-expressed in the Chi- nese stalagmite δ 18O records. This YD-type event is characterized by a large decrease in δ 18O value as much as 2.30‰, more than half of the δ 18O excursion between glacial/interglacial periods, and lasts 1371±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74±4 a. Our data corroborate the view that the re- peated occurrence of YD-type event was not an “accident”, possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.

关键词： stalagmite, Termination 3, Asian monsoon, YD-type event, Shennongjia, Hubei Province.

Characteristic modules of quasi-hereditary algebras with three samples

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Chinese Science Bulletin 1997年第6期42卷 450-454页

作者： ZHANG Pu and LIN Yanan1. department of Mathematics, university of Science and Technology of China, Hefei 2.002., China 2. department of Mathematics, Xiamen university, Xiamen 361005, China department of Mathematics University of Science and Technology of China Hefei China department of Mathematics Xiamen University Xiamen China

CLINE et al. have introduced the concept of quasi-hereditary algebra, which provided a

关键词： tilting module characteristic module quasi-hereditary algebra.

Dimension and measure theoretic entropy of a subshift in symbolic space

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Chinese Science Bulletin 1997年第14期42卷 1193-1196页

作者： CHEN Ercai and XIONG Jincheng1. department of Astronomy, Nanjing university, Nangjing 2.0093, China 2. department of Mathematics, South China Normal university, Guangzhou 510631, China department of Astronomy Nanjing University Nangjing China department of Mathematics South China Normal University Guangzhou China

1 Definitions and resultsWITH the development of the theory of dynamical systems and fractal geometry, one provedthat symbolic dynamics is a powerful tool to study chaos and fractals. It is useful to study thefractal characteristics of symbolic dynamics. In the present note we shall point out the relationbetween the dimension and measure theoretic entropy of any subshift in symbolic space. Weprove here that the Bowen’s formula for Hausdorff dimension holds without Markov struc-ture. A variational principle for dimension is obtained.

关键词： symbolic space subshift measure theoretic entropy dimension.

A new ordered phase forming during ageing in Cu-Ti alloys

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Chinese Science Bulletin 1997年第19期42卷 1671-1672页

作者： WEI Yinghui and WANG Xiaotian1. department of Materials Science, Taiyuan university of Technology, Taiyuan 03002., China 2. {2. of Materials Science, Xi’an Jiaotong university, Xi’an 710049, China Ion Beam Laboratory Shanghai Institute of Metallurgy Chinese Academy of Sciences Shanghai 200050 China

AGE-hardened Cu-Ti has been an important alloy of investigation in the field of continuousphase transformation due to its complicated transformation processes which involve short rangeordering (SRO), spinodal decomposition (SD), long range ordering (LRO), etc. So far, ithas been a controversial topic whether each process exists, and in what sequence they pro-ceed.

关键词： Ti Cu A new ordered phase forming during ageing in Cu-Ti alloys

Diffusion tensor imaging of neural tract injury in a patient with hypoxic-ischemic brain injury

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Neural Regeneration Research 2010年第23期5卷 1825-1828页

作者： Ji Heon Hong,Sung Ho Jang department of Physical medicine and Rehabilitation,{2. of medicine,Yeungnam university,Daegu 705-717,Republic of Korea department of Physical medicine and Rehabilitation College of MedicineYeungnam University Sung Ho Jang

Hypoxic-ischemic brain injury （HI-BI） is one of the most common causes of severe neurological disability, Some studies have reported diffusion tensor imaging （DTI） findings of neonatal patients with HI-BI. However, very little is known about DTI in the adult brain. The present study reports on a 15-year-old male patient with HI-BI, who exhibited no specific focal lesions on conventional brain MRI at 5 weeks. However, neural tract injuries were revealed by DTI. Seven control subjects were also evaluated. The patient suffered from cardiac arrest due to ventricular fibrillation for a period of 10 15 minutes. At 4 weeks after onset of cardiac arrest, although he was conscious and alert, he exhibited mild quadriparesis and severe cognitive dysfunction. DTI was acquired at 5 weeks after HI-BI onset. Decreased fractional anisotropy or voxel number of neural tracts suggested partial injury of the corticospinal tract, fornix, and cingulum. Disruptions of the fornix and cingulum on DTI confirmed neural tract injury. DTI could serve as a useful tool for evaluating the state of neural tracts in patients with HI-BI.

关键词： hypoxic-ischemic brain injury diffusion tensor imaging hemiparesis corticospinal tract

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. department of Marine Environmental Engineering, Dalian Maritime university, Dalian 11602., China E mail: deqi@*** 2. department of Environmental Engineering, SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSia) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural Science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application Science and Technology, Harbin university of Science and Technology, Harbin 150080, China 2. department of Precision Instruments, Tsinghua university, Beijing 100084, China) School of Application Science and Technology Harbin University of Science and Technology Harbin 150080 China department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Parabolic equation of the m-Laplacian with nonlinear boundary condition

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Chinese Science Bulletin 1998年第11期43卷 905-908页

作者： WANG Shu+ 1, 2. WANG Mingxin 3, XIE Chunhong 1 1. department of Mathematics, Nanjing university, Nanjing 2.0093, China 2. department of Mathematics, Henan university, Kaifeng 475001, China 3. department of Applied Mathematics, Southeast university, department of Mathernntics Nanjing University Nanjing China department of Mathematics Henan University Kaifeng China department of Applied Mathematics Southeast University Nanjing China

The existence and nonexistence of global positive weak solutions of parabolic equation of the m-Laplician with nonlinear boundary condition are dealt with. The necessary and sufficient conditions on the existence of a... 详细信息

关键词： nonlinear boundary condition parabolic equation of m-Laplacian global solution blow-up.

Minocycline inhibits 5-lipoxygenase activation and brain inflammation after focal cerebral ischemia in rats

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Acta Pharmacologica Sinica 2007年第6期28卷 763-772页

作者： Li-sheng CHU~(2.3),San-hua FANG~2.Yu ZHOU~2.Guo-liang YU~2.Meng-ling WANG~2.Wei-ping ZHANG~2.Er-qing WEI~(2.4)~2.department of Pharmacology,School of medicine,Zhejiang {2.,Hangzhou 310058,China ~3 department of Physiology ZhejiangChinese Medical {2. Hangzhou 310053,China department of Pharmacology School of Medicine Zhejiang University Hangzhou 310058 China

Aim:To determine whether the anti-inflammatory effect of minocycline on postis-chemic brain injury is mediated by the inhibition of 5-lipoxygenase （5-LOX）expression and enzymatic activation in ***:Focal cerebral ischemiawas induced for 30 min with middle cerebral artery occlusion,followed *** ischemic injuries,endogenous IgG exudation,the accumulationof neutrophils and macrophage/microglia,and 5-LOX mRNA expression weredetermined 72.h after reperfusion.5-LOX metabolites （leukotriene B4and cysteinylleukotrienes） were measured 3 h after ***:Minocycline （2..5and 45 mg/kg,ip,for 3 d） attenuated ischemic injuries,IgG exudation,and theaccumulation of neutrophils and macrophage/microglia 72.h after *** inhibited 5-LOX expression 72.h after reperfusion and the production ofleukotrienes 3 h after reperfusion,Conclusion:Minocycline inhibited postis-chemic brain inflammation,which might be partly mediated by the inhibition of5-LOX expression and enzymatic activation.

关键词： minocycline 5-1ipoxygenase leukotriene focal cerebral ischemia inflammation