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ZHU Zhaoliang XIONG Zhengqin& XING Guangxi State Key Laboratory of Soil Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing China 《中国科学:生命科学英文版》2005,48(Z2)
Asia is the major consumer of fertilizer nitrogen and energy in the world, and consequently shares a considerable proportion of the world creation of reactive nitrogen (Nr). However, if estimated on per capita basis, Asia is characterized by a lower arable land area, fertilizer nitrogen consumption, energy consumption, and gross domestic product, as well as lower daily protein intake. To meet the increasing needs for food and energy for the growing population combined with the improvement of living standards, Nr will inevitably increase. The present study estimates the creation of Nr and the emissions of various N compounds into environment in Asia currently and in 2030. In comparison with the world averages, the lower fertilizer nitrogen and energy use efficiencies, and the lower use of animal wastes for agriculture imply that there is potential for moderating the increase in Nr and its impacts on the environment. Strategies for moderating the increase are discussed. 相似文献
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Yun Zhen CAO * Hong Zhou LU The AIDS Research Center Chinese Academy of Medical Sciences Peking Union Medical College Beijing China Department of Infectious Diseases Shanghai/FuDan Public Health Center & Huashan Hospital Fudan University Shang- hai China 《Cell research》2005,(Z1)
INTRODUCTION Compared with other areas with high HIV infection rate in the world, the total HIV infection rate in China is rela- tively low. Nonetheless, in light of China’s vast territory and large population, the potential infection risk must be taken … 相似文献
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Ahmadreza Mehrabian ;Alireza Naqinezhad ;Abdolrassoul Salman Mahiny ;HosseinMostafavi ;Homan Liaghati ;Mohsen Kouchekzadeh 《Acta Botanica Sinica》2009,(3):251-260
Arid regions of the world occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced. 相似文献
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《云南植物研究》1979,(1)
This work is a preliminary study on the Chinese species of the familyMniaceae,there are about 12 genera and more than 100 species of this familyhave thus far been discovered in the world.This family is a representativeplant group of the Temperate Zones of the Northern Hemisphere.It is mostwidely distributed in the Eastern Asia,especially in China. 相似文献
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Construction of a cucumber genetic linkage map with SRAP markers and location of the genes for lateral branch traits 总被引:7,自引:0,他引:7
WANG Gang * PAN Junsong * LI Xiaozun HE Huanle WU Aizhong & CAI Run Agriculture Biology School of Shanghai Jiaotong University Shanghai China 《中国科学:生命科学英文版》2005,48(3):213-220
Cucumber (Cucumis sativus L. 2n = 2x = 14), thatbelongs to Cucurbitaceae family, is one of majorvegetables with a planting area second to that of to-mato in the world[1]. Due to its economical importanceplant breeders and geneticists have paid much atten-tion to the genetic study on this important vegetablecrop, but the research progress in cucumber is muchless than that in tomato. In 1990, Pierce[2] reviewed allthe reported genes of cucumber that had been geneti-cally analyzed since the 1930… 相似文献
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<正>Rice is one of the most important staple crops, feeding half of the world’s population. In the 1990s, rice became a model plant to study monocots due to its relatively small genome and efficient transformation system(Izawa and Shimamoto, 1996).Rice is the first crop with a sequenced and assembled reference genome(Wang and Han, 2022), and rice genes have been cloned via the map-based cloning system, 相似文献
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Xu Chen Haining Lu Zhengru Ren Yuqiu Zhang Ruoxuan Liu Yunhai Zhang Xingguo Han 《Plant Diversity》2024,(2):256-264
Tall clonal grasses commonly display competitive advantages with nitrogen(N) enrichment. However, it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover, it is unclear whether the height of the vegetative or reproductive system regulates the probability of extinction and colonization, and determines species diversity. In this study, the impacts on clonal grasses were studied in a field experiment employing two frequencies(twice a year vs. monthl... 相似文献
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Lian-Wei Peng Jin-Kui Guo Jin-Fang Ma Wei Chi Li-Xin Zhang 《植物学报(英文版)》2006,48(12):1424-1430
In a previous study, we characterized a high chlorophyll fluorescence Ipal mutant of Arabidopsis thallana, in which approximately 20% photosystem (PS) Ⅱ protein is accumulated. In the present study, analysis of fluorescence decay kinetics and thermoluminescence profiles demonstrated that the electron transfer reaction on either the donor or acceptor side of PSII remained largely unaffected in the Ipa1 mutant. In the mutant, maximal photochemical efficiency (Fv/Fm, where Fm is the maximum fluorescence yield and Fv is variable fluorescence) decreased with increasing light intensity and remained almost unchanged in wildtype plants under different light conditions. The Fv/Fm values also increased when mutant plants were transferred from standard growth light to low light conditions. Analysis of PSll protein accumulation further confirmed that the amount of PSll reaction center protein is correlated with changes in Fv/Fm in Ipal plants. Thus, the assembled PSll in the mutant was functional and also showed increased photosensitivity compared with wild-type plants. 相似文献
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Synopsis of Leymus Hochst. (Triticeae: Poaceae) 总被引:1,自引:0,他引:1
Leymus is a genus in the Triticeae tribe, Poaceae. The taxa of this genus are allopolyploid species which possess the Ns and Xm genomes. According to cytological, cytogenetic and molecular genetic analyses, some species of Hystrix and Elymus ought to be transferred to this genus. A world revision of the genus Leymus is needed. In this paper we summarize experimental results, provide a key to sections, species and varieties, and list all the taxa we recognize in Leymus with their synonyms. This synopsis is a new taxonomic system to be used for the revision of Leymus. 相似文献
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Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tree peonies.However,only several wild populations remain in the Yarlung Zangbo Valley(Nyingchi and Shannan regions,Xizang) in China due to increasing anthropogenic impact on the natural habitats.We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of gen... 相似文献
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《Cell research》2003,(6)
General InformationCell Research is a peer-reviewed, bimomthly journal in English dedicated to providing worldwide significant original achievements in all areas of Cell Biology. It publishes variety and high-quality complete articles of Original research papers, Reviews/Minireviews, Short communications and Commentaries as well express reports in print and electronic version, full text of the journal since 1999 can be freely accessed on line at the web site: http://www.cell-research.com. In recent years, Cell Research is well-cited in the world with impact factor around 2.0. 相似文献
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M.G.Murtaza M.Ferdows J.C.Misra E.E.Tzirtzilakis 《International Journal of Biomathematics》2019,(3):207-226
The present paper deals with the study of three-dimensional boundary layer flow of biomagnetic Maxwell fluid over a plane horizontal surface stretched linearly along two mutually perpendicular directions. Basic principles of magnetohydrodynamics (MHD) and ferro-hydrodynamics (FHD) have been employed. The effect of heat generation/absorption has been taken into consideration. The study is theoretical and is conducted by using a combination of approximate and numerical techniques. By using the method of similarity transformation, the governing nonlinear partial differential equations are converted into a set of coupled ordinary differential equations. In the sequel, a suitable numerical method has been developed to solve the coupled differential equations. The accuracy of the numerical method has been checked by comparing the numerical results with those of an earlier study reported in available literatures. Effects of various parameters involved in the study, viz. the magnetohydrodynamic and ferromagnetic parameters, Deborah number, stretching ratio and heat generation on the fluid flow profiles are investigated and the results have been presented graphically. Variations of the skin friction, heat transfer rate and relative wall pressure with change in hydrodynamic and ferromagnetic parameters have also been illustrated. It is found that due to the influence of the Kelvin force, the velocity component in xx-direction is greater than the corresponding one in the hydrodynamic case, but the opposite is true for the velocity component in the yy-direction. We also found that the temperature of the fluid for hydrodynamic flow is greater than that for MHD or FHD flow. It is even greater for BFD flows. The numerical results of the study reveal that the characteristics of blood flow are significantly affected by the presence of a magnetic field. 相似文献
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Mingxiao Ma 《Virologica Sinica》2014,(6)
正Over the last several years,major efforts have been expended to study viral infection of honeybees mainly due to colony losses around the world(Allen M,et al.,1996).It seems that honeybees are infected with numerous viruses mounting to 18so far.Infection may be asymptomatic but could still have adverse effects on the bee and may even cause death resulting in colony collapse.Sacbrood virus(SBV)is the most widely distributed of all honey bee viruses. 相似文献
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Salihu Sabiu Musa Shi Zhao Nafiu Hussaini Abdulrazaq Carba Habib Daihai He 《International Journal of Biomathematics》2020,(1):163-185
Meningococcal meningitis(MCM)is one of the serious public health threats in the tropical and sub-tropical regions.In this paper,we propose an epidemic model to study the transmission dynamics of MCM with high-and low-risk susceptible populations.The model considers two different groups of susceptible individuals depending on the availability of medical resources(MR,including hospitals,health workers,etc.),which varies the infection risk.We find that the model exhibits the phenomenon of backward bifurcation(BB),which increases the difficulty of MCM control since the dynamics are not merely relying on the basic reproduction number,TZo.This study explores the effects of MR on the MCM epidemics by mathematical analysis and shows the existence of BB on MCM disease.Our findings suggest that providing adequate MR in a community is crucial in mitigating MCM incidences and deaths,especially,in the MCM endemic regions. 相似文献
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《Cell research》2002,(1)
Order for Journals or Reprints please contact directly with Editorial OfficeThe Journal is online with full text beginning from Vol. 9(1), 1999. http://www.cell-research.comAims and ScopeCell Research is a journal devoted to the publication of the novel results in different areas of animal and plant cell biology and to the promotion of the scientific exchanges between China and all other parts of the world. The journal was founded by Shanghai Institute of Cell Biology, Chinese Academy of… 相似文献