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Science China Earth Sciences 1999年第4期42卷 358-368页

作者：姚檀栋

Based on a comparative study of the Guliya ice core with the Greenland GRIP ice core, the abrupt climatic changes on the Tibetan Plateau during the Last Ice Age have been examined. The major stadial-interstadial events and 7 warm events (Brφrump, Odderade, Oerel, Glinde, Hengelo, Denekamp, BQlling) are consistent in the two ice cores. However, there are some unique features in the Guliya ice core records. The transition from warm to cold periods in the Guliya ice core is faster than that in the Greenland GRIP ice core. The magnitude of the climatic changes in the Guliya ice core is also larger than that in the Greenland GRIP ice core. Another significant feature of the Guliya ice core records is that there is a series of cycles of about 200 a from 18 to 35 kaBP. 22 warm events and 20 cold events with a fluctuation magnitude of 71 have been distinguished. The warm and cold events with a fluctuation magnitude within 3 ℃ are as high as 100. It is speculated that the abrupt climatic changes in different periods are caused by different driving forces. The abrupt climatic changes from stadial to interstadial are driven by insolation and are amplified by the snow cover on the Tibetan Plateau. The abrupt climatic changes on shorter time scales are the consequence of interaction between sun activity and the monsoon.

关键词： Guliya ice core GRIP ice core abrupt climatic change comparison.

Environmental changes reflected by the lake sediments of the South Hongshan Lake, Northwest Tibet

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Science China Earth Sciences 2002年第5期45卷 430-439页

作者：朱立平陈玲李炳元李元芳夏威岚李建国 Research Institute of Geographic Sciences and Natural Resources Chinese Academy of Sciences Beijing 100101 China Research Institute of Geographic Sciences and Natural Resources Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University Beijing 100875 Chi

The 1.07-m long lake core with 1 cm interval cutting, which was obtained by drilling in the South Hongshan Lake of Northwest Tibet, was dated by the 210Pb and 137Cs methods, and a 150-year consecutive lake sedimentary sequence (1840─1997) with 1.4 year resolution was obtained. Some environmental proxies, such as the total organic carbon (TOC), total nitrogen (TN), ratio of TOC to TN (TOC/TN), trace chemistry elements (TCE), CaCO3, grain size, richness of ostracoda etc. showed that they are of well coincidence. These results implied that the environmental background varied from the cold-wet period in the late 19th century, to the warm-wet period from the end of the 19th century to the 1920s and to the warm-dry period since the 1920s. There were sub-variations since the 1920s: the cold-dry/warm-wet fluctuation from 1922 to 1960, the intensively warm-dry period since 1960 with a short cold-wet period in the mid-1970s to the end of the 1980s. The humid period from the mid-1970s to the end of the 1970s and the dry period beginning from the early 1980s were well documented by climatic data of the nearby weather station records while the grain size was well correlated to the annual precipitation. Compared with the records from Guliya ice core in the same area, the TOC proxy in the lake core indicating warm/cold conditions well corresponded to the ( 18O records representing temperature variations in the ice core. However, the proxies with dry/wet significance in the lake core were different from the variations of snow accumulation reflected by the ice core. It can be concluded that the chosen environmental proxies have clear environmental significance and the lake sediments can reflect climatic and environmental changes at high-resolution.

关键词： South Hongshan Lake, lake sediments, environmental changes, high resolution, comparison.

Change Laws of Intensity of Moderate-Small Earthquakes (2.0≤Ms≤5.5)

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Earthquake Research in China 1997年第4期11卷 72-80页

作者： Du XingxinSeismological Bureau of Shaanxi Province,Xi’an 710068,China

The change laws of intensity of nearly 200 moderate-small earthquakes with Ms=2.0~5.5 occurring on the Chinese mainland since 1954 have been analyzed and are compared with that of moderately strong earthquakes(Ms≥5.0).The results show that there is quite obvious regionality in the statistical laws by both moderate-small earthquakes and moderately strong earthquakes:attenuation of intensity in Eastern China is slower than that in Western China and the ratio of the major axis to the minor axis of iso-seismal lines in Eastern China is smaller than that in Western *** results also show that for a fixed magnitude the attenuation of intensity of moderate-small earthquakes is faster when intensity is higher than V+ and slower when intensity is lower than V-in comparison.with that of moderately strong ***,there also have been some differences in the aspects as intensity-magnitude relation between statistical laws of moderate-small earthquakes and moderately strong ***

关键词： intensity moderate-small earthquakes statistical law comparison.

Asymptotic Behavior of Solution to Some Models Involving Two Species All with Chemotaxis

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Journal of Partial Differential Equations 2009年第3期22卷 266-281页

作者： LI Junfeng LIU Weian School of Mathematics and Statistics Wuhan University Wuhan 430072 China

This paper is concerned with the asymptotic behavior of solution to the following model involving two species all with chemotaxis：{αp/αt=Dp△（p△lnp/w）,αp/αt=Dq△（q△lnq/w）,αw/αt=βp-δw,p△ln（p/w）.^-n=q△ln（q/w）.^-n=*** prove that the solution exists globally asβ ≥ 0. Asβ 〈 0, whether the solution exists globally or not depends on the initial data. By function transformation and compari- son, the asymptotical behavior of the solution is studied.

关键词： Chemotaxis model asymptotical behavior of solution blow-up quenching comparison.

Tracking, Obedience and Defense between Belgian Shepherd Malinois and German Shepherd Dog

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Journal of Life Sciences 2013年第1期7卷 89-91页

作者： Ivana Gardifinova Martina Helclova Stanislav Korab Lenka Hradecka Demonstrational and Experimental Workplace Faculty of Agrobiology Food and Natural Resources Czech University of LifeSciences Prague Prague 6 Suchdol 165 21 Czech Republic Police of Czech Republic Group of Special Dog Operations Czech Republic Department of Animal Husbandry and Ethology Faculty of Agrobiology Food and Natural Resources Czech University of LifeSciences Prague Prague 6 Suchdol 165 21 Czech Republic

Dogs are used for centuries as people helpers. One of possible use is a sport and service. BSM （Belgian Shepherd Malinois） and GS （German shepherd） dogs are most used breeds like service dogs and also most represented at sports competitions. Our aim was to compare the results of these breeds in the World Cup of International tests of working dogs （in years 2003-2011）, which is the peak of competitions. The authors evaluated results of German shepherd dog performance test and Belgian shepherd Malinois performance in disciplines such as tracking, obedience and defense. Belgian Shepherds achieved in all disciplines higher score than German shepherds. It was found out that Belgian shepherd Malinois get significant higher score in all disciplines （tracking, obedience and defense） than German shepherd. However, both of breeds are used successfully as service dogs.

关键词： German shepherd dog Belgian shepherd Malinois performance test comparison.

Comparative Analysis of New Horizon College English and Experiencing English

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International Journal of Technology Management 2013年第7期 90-91页

作者： Ying Zhang Jilin Medical College JilinChina

College English plays a vital role in English teaching in China. However, any teaching is inseparable from the assistance of teaching material. Among the various English teaching materials currently, what are most often used are Experiencing English and New Horizon College English. These two English teaching materials are both adapted according to new teaching syllabus and the practical teaching needs. Both teaching materials have their own advantages and disadvantages.

关键词： College English New Horizon Experiencing English Teaching material comparison.

A New Bioassay Method for Evaluation Allelopathic Potential of Rice Germplasm

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Journal of Life Sciences 2016年第3期10卷 128-133页

作者： Yongliang Lu Hong Lu Kilung Kim Yiding Sun Jian Fu Yiqing Guo ChinaNationalRiceResearchInstitute ChineseAcademyofAgriculturalSciencesHangzhou310006China NationalCenterforAgro-Biodiversity/YunnanAgriculturalUniversity Kunming650201China CollegeofAgricultureandLifeScience KyungpookNationalUniversityDaegu702-701Korea Biotchnology&GermplasmResourceInstitute YunnanAcademyofAgriculturalSciencesKunming650223China

Allelopathy was defined in 1996 by IAS （international allelopathy society） as any process involving secondary metabolites produced by plant, algae, bacteria and fungi that influences the growth and development of agricultural and biological systems. Rice allelopathy against weeds was reported since 1989, which offers an integrated weed management with substantially reduced herbicide usage. Application of allelopathic rice cultivars is thought a resources conservation and environmental friendly way of weed bio-control, and could promote the sustainable development of agriculture. Screening or evaluating the allelopathic potential rice variety is the first step. In this paper, a new bioassay method was set up by the allelopathic potential of 9 rice lines on the target weed barnyardgrass （Echinochloa crusgalli）, and comparing with bioassay methods such as relay seeding in filter paper （RSF） and relay seeding in agar （RSA）. The results indicated that three methods had a same tendency in evaluating the allelopathic potential of rice; there existed a significant difference among different bioassay methods, and an interaction between bioassay methods and rice lines. The method of root exudates （RE） with the highest value and a correlation efficiency of 0.98 was considered as ideal bioassay method for evaluation of allelopathic potential.

关键词： Rice allelopathic potential bioassay methods comparison.

Earthworm Fibrinolytic Isozymes Ⅲ-l and Ⅱ from Eisenia fetida

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Earthworm Fibrinolytic Isozymes Ⅲ-l and Ⅱ from Eisenia fet...

Study on the Traditional Classroom Learning and the Autonomous Learning

第七届全国酶学学术讨论会

作者： Jing Zhao. Yan-Jun Chen, Jian He, Ya-Qun Zhang, Run-Sheng Chen and Rong-Qiao He Laboratory of Visual Information Processing, Center for Brain and Cognitive Sciences, Institute of Biophysics, Graduate School, Baiao Pharmaceuticals Beijing C.L., CAS, Beijing 100101, China.

Earthworm has been used as a traditional medicine to treat clotting diseases in eastern countries for centuries. In Compendium of Materia Medica edited by a Chinese traditional medical doctor Shizhen Li (1518-1593), earthworm was described as a kind of drug prescribed for antipyretic and diuretic purposes in clinic. Two earthworm fibrinolytic enzymes (EFEs), EFE-Ⅲ-1 and EFE-Ⅱ, are isolated and purified from an earthworm Eisenia fetida by affinity chromatography. Both EFE-Ⅲ-1 and EFE-Ⅱare heat-resist and stable proteases. Substrates specificity and inhibition assays show that EFE-Ⅲ-1 is a trypsin-like protease, and EFE-Ⅱacts strongly as a thrombin-like serine protease and a relatively weak elastase-like function. Fibrinogen, plasminogen and prothrombin are employed to investigate the characteristics of EFE-Ⅲ-1 and EFE-Ⅱin reactions. Additionally, these three molecules are essential participants in blood coagulation cascade. EFE-Ⅲ-1 mainly acts on alkaline ammo acid residues (K-X, R-X). Meanwhile, EFE-Ⅱhas a broader specificity than EFE-Ⅲ-1, and hydrolyzes the bonds consisting of neutral or hydrophobic amino acids, especially in the hydrophobic region, and the sites involved in aromatic specificity. The two isozymes can hydrolyze the three chains of fibrinogen, and the a-fibrinogenase-like activity is the strongest, while γ-fibrinogenase-like is the lowest. From the cleavage sites of prothrombin, EFE-Ⅱmight have the similar function as factor Xa on activating prothrombin (into thrombin) in two ways. EFE-Ⅲ-1 and EFE-Ⅱdirectly hydrolyze fibrin(ogen), at the same time they partially activates prothrombin to improve coagulation. EFE-Ⅲ-1 can catalyze the conversion of plasminogen to active plasmin other than EFE-Ⅱ. Polyconal antibody against EFE-Ⅲ-1 shows a high specificity to its antigen, while antiserum against EFE-Ⅱhas immunogical reactions with both EFE-Ⅲ-1 and EFE-Ⅱ. The fibrinolytic activity of EFE-Ⅲ-1 is approximately six times higher than that of EFE-Ⅱ. On the basi

关键词： Fibrinolytic function Earthworm Fibrinolytic Enzyme EFE-Ⅲ-1 EFE-Ⅱ comparison.

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Study on the Traditional Classroom Learning and the Autonomo...