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Miocene Bahean stratigraphy in the Longzhong Basin, northern central china and its implications in environmental change

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science china Earth sciences 2006年第12期49卷 1270-1279页

作者： LI Jijun1,2, zhang Jun1, SONG Chunhui1, ZHAO Zhijun2, zhang Yong1, WANG Xiuxi 1, zhang Jianming1 & CUI Qiaoyu1 1. Key Laboratory of Western china’s Environmental Systems (Ministry of Education) & college of Earth and Environment sciences, Lanzhou university, Lanzhou 730000, china 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography, nanjing Normal university, nanjing 210097, china 1. Key Laboratory of Western china’s Environmental Systems (Ministry of Education) & college of Earth and Environment sciences Lanzhou University Lanzhou 730000 China 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography Nanjing Normal University Nanjing 210097 China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central china. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.23 Ma) and shallow lake sediments at the top (9.23―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

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Morroniside protects cultured human umbilical vein endothelial cells from damage by high ambient glucose

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Acta Pharmacologica Sinica 2004年第4期25卷 14-17页

作者： Hui-qin XU2, Hai-ping HAO2, Xu zhang3,Yang PAN2 2college of Pharmacy 3BasicMedicine college, nanjing universityof Traditional ChineseMedicine, nanjing 210029, china college of Pharmacy Basic Medicine college Nanjing University of Traditional Chinese Medicine

AIM: To determine whether morroniside, a compound in Cornus officinalis Sieb et Zucc can prevent cultured human umbilical vein endothelial cells (HUVEC) from damage by high ambient glucose. METHODS: HUVEC was incubated in glucose, 5 or 30 mmol/L, either alone or in the presence of morroniside (final concentration 100, 10, and 1 μmol/L, respectively) for 48 h. The proliferation of HUVEC was quantified by MTT method; its cycle was analyzed by flow cytometry; morphological change was observed with fluorescence microscopy. RESULTS: Survival of HUVEC cultured in high ambient glucose was significantly decreased when compared to that in normal concentration of glucose (P<0.01). High ambient glucose also lowered the rate of cells entering into S-phase, along with severe morphological damage. With the intervention of morroniside (final concentration 100 and 10 μmol/L), the cell survival was significantly recovered (P<0.01, P<0.05, respectively), accompanied with increased S-phase rate and less extent of morphological damage. CONCLUSION: Morroniside protected HUVEC against high ambi- ent glucose induced injury, which suggested that morroniside could exert a beneficial effect on preventing diabetic angiopathies.

关键词： morroniside umbilical veins endothelial cells diabetic angiopathies

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A new policy to solve routing conflicts in shuffle-exchange networks

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science china(Information sciences) 2011年第7期54卷 1512-1523页

作者： GE FangBin 1,ZHAO Min 1,zhang Tao 1 & WANG JianXin 2 1 college of Command Automation PLA university of science and Technology,nanjing 210007,china 2 Institute of china Electronic System Engineering,Beijing 100039,china 1. college of Command Automation PLA university of science and Technology Nanjing 210007 China2. Institute of China Electronic System Engineering Beijing 100039 China

Batch routing is an important approach for solving routing conflicts in SE (shuffle-exchange) ***,the complexity of batching and the uncertainty of batch size makes this approach *** on sequence division and routing coding concepts,we propose a method for detecting routing conflicts in an SE network,known as dividing detection that is more efficient than the method for window *** addition,a new conjecture relating to routing policies in SE networks is *** is proved using a constructive approach when n < *** on the conjecture,a new routing scheme for SE networks is *** this scheme,all the input signals can be transfered without conflicts and within two batches,while the efficiency of the batch routing is noticeably improved.

关键词： shuffle-exchange network sequence division routing coding transition sequence educed sequence

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Distribution and Migration of Heavy Metals in Undisturbed Forest Soils:A High Resolution Sampling Method

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Pedosphere 2008年第3期18卷 386-393页

作者： RUAN Xin-Ling zhang Gan-Lin NI Liu-Jian HE Yue State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of sciences Nanjing 210008 （China） Graduate School of the Chinese Academy of sciences Beijing 100049 （China） college of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 （China）

The vertical distribution and migration of Cu,Zn,Pb,and Cd in two forest soil profiles near an industrial emission source were investigated using a high resolution sampling method together with reference element ***-meter soil profile was sectioned horizontally at 2 cm intervals in the first 40 cm,5 cm intervals in the next 40 cm,and 10 cm intervals in the last 20 *** migration distance and rate of heavy metals in the soil profiles were calculated according to their relative concentrations in the profiles,as calibrated by the reference element *** enrichment of heavy metals appeared in the uppermost layer of the forest soil,and the soil heavy metal concentrations decreased down the profile until reaching their background *** calculated average migration rates of Cd,Cu,Pb,and Zn were 0.70,0.33,0.37,and 0.76 cm year-1,respectively,which were comparable to other methods.A simulation model was proposed,which could well describe the distribution of Cu,Zn,Pb,and Cd in natural forest soils.

关键词： distribution heavy metals high resolution sampling method migration rate

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Air flow exploration of abrasive feed tube

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Acta Mechanica Sinica 2009年第6期25卷 761-768页

作者： Shijin zhang Xiaohong Li Yilei Gu college of Resources and Environmental science,Chongqing university, 400044 Chongqing, china college of Resources and Environmental science Chongqing University 400044 Chongqing China

An abrasive water-jet cutting process is one in which water pressure is raised to a very high pressure and forced through a very small orifice to form a very thin high speed jet beam. This thin jet beam is then directed through a chamber and then fed into a secondary nozzle, or mixing tube. During this process, a vacuum is generated in the cham- ber, and garnet abrasives and air are pulled into the chamber, through an abrasive feed tube, and mixes with this high speed stream of water. Because of the restrictions introduced by the abrasive feed tube geometry, a vacuum gradient is generated along the tube. Although this phenomenon has been recog- nized and utilized as a way to monitor nozzle condition and abrasive flowing conditions, yet, until now, conditions inside the abrasive feed line have not been completely understood. A possible reason is that conditions inside the abrasive feed line are complicated. Not only compressible flow but also multi- phase, multi-component flow has been involved in inside of abrasive feed tube. This paper explored various aspects of the vacuum creation process in both the mixing chamber and the abrasive feed tube. Based on an experimental exploration, an analytical framework is presented to allow theoretical calculations of vacuum conditions in the abrasive feed tube.

关键词： Abrasive feed tube- Water jet cutting. Vacuum gradient

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A new generation of plastic optical fibers and its functional exploiting

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science china(Technological sciences) 2008年第12期51卷 2197-2207页

作者： YU RongJin & zhang Bing college of Information science and Engineering,Yanshan university,Qinhuangdao 066004,china college of Information science and Engineering Yanshan University Qinhuangdao 066004 China

A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica *** adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved *** the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000 μm).This new generation of POFs will find many applications.

关键词： plastic optical fiber hollow-core Bragg fiber cobweb-structured cladding visible light infrared light terahertz wave circular-polarization single-mode

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Artificial Induction of Twinning by an Active Immunization of Beef Cows Against Inhibin Partially Purified from Porcine Seminal Plasma

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agricultural sciences in china 2002年第4期1卷 466-471页

作者： YANG Li-guo, zhang Ju-nong, WANG Jin-rong, YE Rong, SANG Run-zi, NIU Shu-li and LIU Cheng-hai( Research Laboratory of Animal Reproduction , college of Animal science and Technology, nanjing agricultural university,nanjing 210095 , china college of Animal science and Technology, Shihezi agricultural university, Shihezi 832003 ,china Department of Animal Husbandry and Veterinary Medicine , Xinjiang agricultural university,Wulumuqi 830000 , china Department of Animal Husbandry and Veterinary Medicine ,Hebei agricultural university, Baoding 071001 , P.R. china) Research Laboratory of Animal Reproduction College of Animal Science and Technology Nanjing Agricultural University Nanjing 210095 China college of Animal science and Technology Shihezi Agricultural University Shihezi 832003 China Department of Animal Husbandry and Veterinary Medicine Xinjiang Agricultural University Wulumuqi 830000 China Department of Animal Husbandry and Veterinary Medicine Hebei Agricultural University Baoding 071001P.R. China

Two hundred and seventy multiparous Chinese Yellow cattle (beef) were selected at 1 to 3 months postpartum and divided into three groups (90 cows for each). Animals were given both a primary and booster immunizations with a total dose of 3 mg (Group Th) or 1.5 mg (Group Tl) of seminal preparation containing inhibin activity, emulsified with Freund's complete adjuvant and incomplete adjuvant (for booster) , at 3 or 4-week intervals. Other cows were treated with the same volume of seminal preparation without inhibin activity as procedures mentioned above to serve as a control (Group C). Artificial inseminations were given twice at 8 - 12 h intervals when the cow was in heat. Jugular venous blood samples were collected from each cow and used to assay the presence of antibody against seminal preparation by double-diffusion in agar precipitation test and to detect the titer of inhibin antibody by an ELISA method. Data from 247 cows showed that 83.9% (73/87) of cows were in estrus and ovulated 89 ova altogether, of which 19 cows ovulated twin ova and 15 cows produced twins in Group Th (n = 87). However, only 61.1% (44/72) of cows in Group TI (n = 72) and 62.5% (55/88) of cows in Group C were in estrus and ovulated 46 and 52 ova altogether respectively. The ovulation rate (1.27 ± 0.03), calving rate (126.3%) and twinning rate (26.3%) in Group Th were greater than those in Groups Tl or C (P<0.01). Furthermore, the ovulation rate was associated with antibody titer in sera of immunized animals (r = 0.7507, P<0.01). These results indicate that active immunization of postpartum cows against inhibin purified from porcine seminal plasma may increase the ovulation rate and induce twinning, suggesting the potential to develop a method to improve fertility in cows.

关键词： Beef cows Seminal inhibin Active immunization Twinning Ovulation rate

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Changes in Dietary Patterns and Certain Nutrition-related Diseases in Urban and Rural Residents of Jiangsu Province,china,During the 1990s

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Biomedical and Environmental sciences 2002年第4期15卷 271-276页

作者： WANG CAN-NAN , LIANG ZHI , WEI PING , LIU PEI , YD JiA-Xr, zhang DAN-MEI, AND MA FENG-LOUFaculty of Public Health, Xuzhou Medical college, Xuzhou, Jiangsu 221002, china Bureau ofHealth, Jiangsu Provincial Government, nanjing, Jiangsu 210008, china Statistical Bureauof Jiangsu Provincial Government nanjing, Jiangsu 210026, china Health andAnti-epidemic Station of Xuzhou, Xuzhou. Jiangsu 221002, china ’ School of PublicHealth, nanjing Medical university, nanjing, Jiangsu 210029, china Faculty of Public Health Xuzhou Medical College 江苏 Xuzhou 221002 Bureau of Health Jiangsu Provincial Government 江苏 Nanjing 210008 Faculty of Public Health Xuzhou Medical Colleg 江苏 Xuzhou 221002 Health and Anti-epidemic Station of Xuzhou 江苏 Xuzhou 221002 School of Public Health Nanjing Medical University 江苏 Nanjing 210029

Objective To investigate into the changes of dietary patterns and their impacts on health of urban and rural residents in Jiangsu Province, china during the 1990s. Methods On the basis of the results of food consumption survey, the calorie intake was calculated according to the balanced diet method and the quality of diet was assessed by scores of desirable dietary pattern (DDP). Results It was found that food consumption and dietary patterns changed remarkably during the 1990s. Grain consumption was decreasing year by year, but the consumption of animal food was markedly increasing. Although the score of desirable dietary pattern (DDP) in urban residents was more than 90, the deducted score due to over-consumption of animal food increased. The mortality from infectious diseases evidently decreased in the whole province, while the death rates of some chronic diseases, such as diabetes, hypertension, colorectal cancer and breast cancer, were increasing rapidly in urban areas. Conclusions Sufficient attention should be paid to the negative effects of change in dietary patterns on people's health, especially in the urban residents.

关键词： Dietary patterns Nutrition-related diseases

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Coupling between elytra of some beetles: Mechanism, forces and effect of surface texture

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science china(Life sciences) 2008年第10期51卷 894-901页

作者： DAI ZhenDong1, zhang YaFeng1, LIANG XingCai2 & SUN JiuRong1,3 1 Institute for Bio-inspired Structure and Surface Engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 2 Kunming Institute of Zoology, Chinese Academy of science, Kunming 650223, china 3 college of Life sciences, Peking university, Beijing 100871, china 1. Institute for Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. Kunming Institute of Zoology Chinese Academy of Science Kunming 650223 China 3. college of Life sciences Peking University Beijing 100871 China

Lightweight materials, structures and coupling mechanisms are very important for realizing advanced flight vehicles. Here, we obtained the geometric structures and morphologies of the elytra of beetles and ascertained its coupling zone by using the histological section technique and SEM. We set up a three-dimensional motion observing system to monitor the opening and closing behaviour of elytra in beetles and to determine the motion mechanism. We constructed a force measuring system to measure the coupling forces between elytra. The results show that elytra open and close by rotating about a single axle, where the coupling forces may be as high as 160 times its own bodyweight, the elytra coupling with the tenon and mortise mechanism, surface texture and opening angle between elytra heavily influence the coupling forces. These results may provide insights into the design mechanism and structure for future vehicles of flight.

关键词： beetle elytra coupling mechanism elytral morphology surface texture

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N Accumulation and Translocation in Four Japonica Rice Cultivars at Different N Rates

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Pedosphere 2007年第6期17卷 792-800页

作者： zhang Yao-Hong FAN Jian-Bo zhang Ya-Li WANG Dong-Sheng HUANG Qi-Wei SHEN Qi-Rong college of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 （China）

Developing high-yielding rice(Oryza sativa L.)cultivars depends on having a better understanding of nitrogen(N) accumulation and translocation to the ear during the reproductive *** experiments were carried out to evaluate the genetic variation for N accumulation and translocation in different Japonica rice cultivars at different N rates and to identify any relationship to grain yield in southeast *** Japonica cultivars with similar agronomic characteristics were grown at two experimental sites in 2004 with three N rates of 0,60,and 180 kg N ha^(-1).Dry weights and N contents of rice plants were measured at tillering,initiation,anthesis,and *** yields exhibited significant differences (Pchina should efficiently increase N-recovery rate while maintaining grain yield and soil fertility.

关键词： rain yield Japonica rice cultivar N accumulation N application rate N translocation

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