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Occurrence and Population Dynamics of Chironomids in Early-Season rice Fields

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rice Science 2011年第2期18卷 136-141页

作者： LI Zhi-yu1, 2, YANG Hong1, LAI Feng-xiang2, FU Qiang2, HU Yang2 (1institute of Entomology, Guizhou University/The Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region, Guiyang 550025, China 2China National rice research institute, Hangzhou 310006, China) [a]institute of Entomology Guizhou University/The Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Guiyang 550025 China [b]China National rice research institute Hangzhou 310006 China

The chironomid is one of the world wide distributed insects and normally occurs in a great abundance among many kinds of water bodies. Currently, our knowledge about the chironomid in rice fields is limited to the species survey, and it is considered as a group insect at the family level, termed as a kind of the neutral insects. By using the specially designed emergence traps, the species richness and the occurrence of the chironomid in rice fields were studied throughout the early season in Fuyang City, Zhejiang Province, China. There were four species, namely, Tanytarsus formosanus, Chironomus sinicus, Polypedilum nubifer and Tanypus punctipennis of chironomids collected from rice fields. All of them are widely distributed species. T. formosanus and C. sinicus were the most dominant species in rice fields. The succession of chironomids in the early season could be divided into two phases, the early and the late phases. The abundance of the chironomid was higher in the early phase than that in the late phase. It was estimated that there were around 3 million individuals of chironomids emerged from 667 m2 rice field throughout the early season. It was also found that the sex ratio of T. formosanus was female-biased during the early phase, whereas male-biased during the late phase. In contrast, the sex ratio of C. sinicus was male-biased throughout the early season.

关键词： rice field chironomid population dynamic sex ratio

Pedosphere and Its Effect on Global Changes

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Pedosphere 2000年第2期10卷 97-106页

作者： ZHAO QIGUO and CAO HUI(institute of Soil Science, the Chinese Academy of Sciences, P.O. box 821, Nauling 210008 China) 中科院南京土壤所江苏南京 210008

With development of modern geoscience, particularly development of environmental sciences, the contemporary soil science is undergoing great changes in both research contents and scope. Soil is not onlya certain substance or a certain independent natural historical body but also a spheric layer with peculiarstructure and functions in the earth system. From the viewpoint of the geo-biosphere system of earth, soilscience does deal not only with the soil substances per se but also more importantly with the relationshipsamong soil, the other spheres and the human survival environment in view of the "pedosphere". This is thenew orientation of soil science today and will affect profoundly the studies on the human survival environmentand global changes. To throw more light on this subject, the present paper intends to address the conceptionof pedosphere and its role in global changes. Also addressed are series of environmental issues in China andtheir relations to the global changes. Moreover, research orientation and priorities are indicated, includingexploitation and protection of the soil resources, soil fertility and sustainable agricultural development, construction of the ecological environment, and the material cycling in pedosphere and its relation to globalchanges.

关键词： earth ecological environment global changes pedosphere soil science

Genetic Diversity and Relationship of Weedy rice in Taizhou City, Jiangsu Province, China

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rice science 2008年第4期15卷 295-302页

作者： Nilda R. BURGOS Department of Crop Soil and Environmental Sciences University of Arkansas

Microsatellite markers and morphological characteristics were used to explore the genetic diversity and possible origin of weedy rice in Taizhou City, Jiangsu Province, China. Fifty-two weedy rice (Oryza sativa L.) accessions were compared with two wild rice, four hybrid rice and five cultivars using 22 simple sequence repeat (SSR) primer pairs. A total of 107 fragments were amplified, averaging 5.6 alleles per primer pair. The polymorphic index content (PIC) values ranged from 0.3077 to 0.7951, averaging at 0.5870. The average genetic distance of all samples ranged from 0.02 to 0.46 with an average of 0.262. The genetic distance among Taizhou weedy rice ranged from 0.03 to 0.44 with an average of 0.224. Cluster analysis showed that all the weedy rice accessions from Taizhou City were indica, and could be subdivided into different genotypes. The majority (86%) of weedy rice was most closely related to hybrid rice. The Taizhou weedy rice accessions were morphologically similar, but still could be delineated into indica or japonica group by some morphological traits. It is suggested that the levels of genetic and morphological diversities of weedy rice in Taizhou City are low and these weedy rice plants originated from the segregating progenies of hybrid rice that had naturally introgressed with cultivated rice.

关键词： weedy rice genetic diversity origin analysis of molecular variance simple sequence repeat

Water Yield and Sediment Yield Simulations for Teba Catchment in Spain Using SWRRB Model: Ⅰ. Model Input and Simulation Experiment

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Pedosphere 2002年第1期12卷 41-48页

作者： ZENG ZHIYUAN and A. M. J. MEIJERINK Collage of Geography, Nanjing Normal University, Nanjing 210097 (China) international institute for Aerospace Survey and Earth Sciences, P. O. box 6, 7500A A Enschede (the Netherlands) Collage of Geography Nanjing Normal University Nanjing 210097 international institute for Aerospace Survey and Earth ScieneesNetherlands) 荷兰

Water yield and sediment yield in the Teba catchment, Spain, weresimulated using SWRRB (Simulator for Water Resources in Rural Basins)model. The model is composed of 198 mathematical equations. About 120items (variables) were input for the simulation, includingmeteorological and climatic factors, hydrologic factors, topographicfactors, parent materials, soils, vegetation, human activities, *** simulated results involved surface runoff, subsurface runoff,sediment, peak flow, evapotranspiration, soil water, total biomass,etc. Careful and thorough input data preparation and repeatedsimulation experiments are the key to get the accurate results. Inthis work in the simulation accuracy for annual water yieldprediction reached to 83.68/100.

关键词： comptuer simulation image processing Spain SWRRB

A MULTI-DIMENSIONAL COMPOSITE MODEL FOR PLASTIC CONTINUA UNDER POLYAXIAL LOADING CONDITION

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Acta Mechanica Sinica 1990年第4期6卷 357-366页

作者： Liang Naigang (institute of Mechanics,Chinese Academy of Sciences,Beijing,100080,P.R.China)Pal G.Bergan (A.S.Veritas research,P.O.box 300,N-1322 Hφuik,Oslo,Norway) 1. institute of Mechanics Chinese Academy of Sciences 100080 Beijing P.R. China 2. A. S. Veritas research H?uik P. O. Box 300 N-1322 Oslo Norway

By replacing a medium with reinforcing components oriented and distributed uniformly in a mul- ti-dimensional space,a constitutive model is *** components are extended/compressed compatibly with the strain and the resultant of load exerted on them to balance the *** load-elongation relation can be determined from a conventional material *** component undergoes different elongation history depending on its own orientation during deformation,so that the model can simulate elasto-plastic behavior of materials un- der polyaxial loading *** incremental constitutive matrix bas been derived for application in numeri- cal analysis and a yield criterion is also introduced.A few subsequent yield surfaces have been predicted and com- pared with experiments.

关键词： plasticity constitutive relationship

Night-time Rise in Rat Pineal N-Acetyltransferase due to Carbaryl Administration Is Reduced by Propranolol Treatment

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Biomedical and Environmental Sciences 1995年第1期8卷 45-53页

作者： AHMED M. ATTIA MOSTAFA H. MOSTAFA BRUCE A. RICHARDSON AND RUSSEL J. REITER(Department of Environmental Studies, institute of Graduate Studies and research, P.O.box 832, Alexandria, Egypt Department of Cellular and Structural Biology, University of Texas, Department of Environmental Studies Institute of Graduate Studies and Research Alexandria Egypt.

The purpose of the present study was to examine the effects of administration of sublethal doses of carbaryl on nighttime rat pineal melatonin synthesis in the presence and absence of propranolol, a β-adrenergic receptor antagonist. Two groups of adult male albino rats were administered orally N-methyl-l-naphthylcarbamate (carbaryl) (8. 33mg/kg BW daily in corn oil) for six successive days; another two groups received corn oil *** the last day of carbaryl treatment, half of the animals received an intraperitoneal injection of propranolol (20 mg/kg body weight, one hour before lights off). The other two groups were given a saline injection. Four hours after darkness onset, pineal N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) activities as well as pineal concentrations of 5-hydroxytryptophan (5HTP), serotonin (5HT),5-hydroxyindole acetic acid (5HIAA) and pineal and serum melatonin levels were measured. Nocturnal NAT activity was increased due to carbaryl administration but the pesticide was ineffective in stimulating NAT activity in rats treated with *** 5HT was decreased due to carbaryl administration but 5HTP and 5HIAA levels were unaffected. Pineal and serum melatonin levels were decreased due to propranolol treatment. The results indicate that carbaryl may influence pineal NAT activity by a mechanism that involves β-adrenergic neural transmission.

关键词： time Night-time Rise in Rat Pineal N-Acetyltransferase due to Carbaryl Administration Is Reduced by Propranolol Treatment

Preparation of Nickel Materials with Fractal Structure

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Journal of Materials Science & Technology 2003年第3期19卷 229-231页

作者： Ruichun WANG, Jingdong GUO Benlian ZHOUShenyang National Laboratory for Materials Science, institute of Metal research, Chinese Academy of Sciences, Shenyang 110016, China Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A way of manufacturing nickel material with fractal structure has been studied. Some algae with natural fractal structure were used as the basic substrates. The nickel was coated on the substrates by both electroless deposition and electrodeposition. After elimination of the foundational algae by erosion, dissolution etc, the pure nickel materials with fractal structure were obtained. At last, the specific surface area was analyzed by BET analyses and the fractal dimension of the nickel material was calculated by means of box-counting technique. The comparison of fractal dimension between Ni structure and natural algae was also given.

关键词： Fractal Nickel Algae box counting

The Time Evolution of Radial Collective Flow in Reaction of ^(197)Au with ^(197)Au at 150 MeV/u

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Chinese journal of nuclear physics 1995年第4期17卷 298-304页

作者： Shen Wen-qing1,2 Xi Hong-fei2,3 A. Gobbi2 N. Herrmann2 K. D. Hildenbrand2 Wang Gao-sheng2 FOPI Collaboration21. CCAST (World Laboratory), P.O. box 8730, Beijing 100080, and institute of Nuclear research, the Chinese Academy of Sciences, P. O. box 800-204, Shanghai 2018002. Gesellschaft fur Schwerionenforschung, D-64229 Darmstadt, Germany3. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 中科院上海原子核所上海中科院近代物理所甘肃兰州 Gesellschaft fur Schwerionenforschung 德国

Dynamical time evolution for central collision of 197 Au on 197Au at 150 MeV/u is in-vestigated by using Isospin-dependent Quantum Molecular Dynamics （IQMD） calculation. Thepreequilibrium emission, its influence and... 详细信息

关键词： IQMD simulation Radial collective flow Multifragmentation Dynamical time evolution

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang University, Hangzhou 310027,China 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China 2institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of Sciences, P.O. box 918, Beijing 100039, China 3Wuhan institute of Physics and Mathematics, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Chinese Academy of Sciences, Wuhan 430071, China Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3) A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis