10 May 2006, Volume 24 Issue 0605

    

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科学家之声
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  The Ideal China Association for Science and Technology in My Mind: Celebrating the 7th National Congress of CAST

  . 2006, 24(0605): 5-7.

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  At the opening of the 7th National Congress of CAST, three wishes for the development of CAST are expressed: the science popularization will be augmented; CAST will become the think tank of the CPC and the government; CAST will focus on not only science and technology, but also education. Lastly, several problems in Chinese higher education those holding back the sci-tech innovation are enumerated and analyzed.
Exclusive
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  Height Determination of Qumolongma Feng (Mt. Everest) in China

  . 2006, 24(0605): 8-11.

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  Since the 1960s, China has carried out six geodetic campaigns (in 1966, 1975, 1992, 1998, 1999 and 2005 respectively) for the height determination of Qumolongma Feng (Mt. Everest, QF in short) independently or in cooperation with foreign countries. Geodetic field work, data processing and scientific researches have been executed in the campaigns. The height determination results of QF obtained by China in the past 40 years have been briefly introduced and reviewed in the paper. Emphases are given to the technical progress in the 2005 campaign. For example, GPS technique has been widely and precisely used, and the thickness of the snow-ice cover on the QF summit is measured by ground penetrating radar integrated with GPS. All these technical measurements really raise the accuracy and reliability for the height determination of QF and the thickness of the snow-ice layer on the QF summit. The orthometric height (height above sea level) of the snow surface of the QF summit is 8 847.93 m. T...更多he orthometric height of rock surface of the QF summit is determined as 8 844.43 m,and the thickness of the snow-ice layer on the QF summit is 3.50 m.
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  Scale-free Property of Complex Systems and its Macro-control

  . 2006, 24(0605): 11-15.

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  Scale-free issues of complex systems, including scale-free property of complex systems, analysis of power law distribution, the evolving mechanisms for scale-free property, scale-free phenomena of complex systems, and macro-control of scale-free property, are systemically researched in this paper. We emphasize that: ①Generally speaking, scale-free property is one of the intrinsic characteristics of complex systems, which describes their overall extremely uneven asymmetry distributions; ②Various complex systems with power-law distribution are highly heterogeneous only when their scaling exponents are between 2 and 3, which is proved theoretically by the authors; ③The macro-control principle for the scale-free property of the very important complex systems involved in the national economy and the people's livelihood is proposed.
医药问题专题
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  Effective Characteristics of Radix Salviae Miltiorrhiae with Radix Notoginseng and New Drug Design Idea on Account of Effectiveness

  . 2006, 24(0605): 25-27.

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  In this article, we give some aggregate analysis of datum about drug action matter and pharmacological empirical study in vivo or vitro, and then summarized effective characteristics and patterns of manifestation for Radix Salviae Miltiorrhiae matching with Radix Notoginseng. As a result, we put forward a new drug design idea on account of compositive-activity relationships.
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  Experimental Study on the Transcriptional Targeting Gene Therapy of Double Suicide Gene Driven by KDR Promotor in Lung Cancer

  . 2006, 24(0605): 28-31.

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  Human kinase domain receptor promoter (KDRp) has been cloned into the pcDNA3 -CDglyTK to construct the pcDNA3-KDRp-CDglyTK specialized expression vector. The pcDNA3-KDRp-CDglyTK plasmid was transfected into ECV304, L9981 and NL9980 cell, and established ECV304-cdtk, L9981-cdtk and NL9980-cdtk cell lines. The above cell lines were treated with 5-FC and/or GCV respectively. The result suggest that cdtk gene was specialized expressed in ECV304-cdtk, L9981-cdtk and NL9980-cdtk KDR-positive cells with KDR gene high expression, and prodrug/KDRp-CDglyTK system was effective in killing effect in KDR-positive cells. The killing effect in combined drug (5-FC and GCV) was remarkable stronger than that in GCV alone and 5-FC alone in the same pre-drug dose, and a significantly synergetic cytotoxic effect was found in vivo and in vitro.
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  Studies of the Relationship between Heterogeneity in Tumors and the Bio-behavior of Invasion and Metastasis of Advanced Gastric Carcinoma

  . 2006, 24(0605): 32-35.

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  In this paper, we report our researches into the changes of nm23, S100A4 and p53 between the primary tumor and the metastases of gastric cancer by immunohistochemistry and polymerase chain reaction single-strand conformation polymorphisms (PCR-SSCP), as well as the role of heterogeneity in the process of metastasis of gastric cancer. The results revealed lower expression of nm23 and higher expression of S100A4 in the metastases than in the primary tumor. No difference of p53 between the two groups was found. Down-expression of nm23 and overexpression of S100A4 and p53 were related to distant metastasis of gastric cancer. The results suggested that nm23 and S100A4 play a critical role in the process of metastasis and that p53 is a late event of gastric cancer.
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  Study of the Impact of Low-level Lead on the Expression of Neural Cell Adhesion Molecule

  . 2006, 24(0605): 36-38.

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  To explore the role of neural cell adhesion molecule (NCAM) on the lead neurotoxicity, the impact of lead on the expression of NCAM was studied with Wistar rats in vitro and in vivo respectively. Results showed that in vivo PbCl2 dose-responsively inhibited the expression of NCAM at 14 d, but till the 30 d, the pups' NCAM expression exceeded the control. The same trend of NCAM expression was observed in vitro. This study indicated that low-level lead significantly inhibited the expression of NCAM in Wistar rats' hippocampus especially at early development time and delayed it's expression phases.
Articles
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  Magnetic Response of Metals in Xuzhou Urban Topsoil

  . 2006, 24(0605): 39-43.

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  Contamination of urban topsoils with metals is an issue all urban regions have to deal with. In recent years, magnetic measurements have been increasingly used as a proxy for the metal content in soils influenced by industrial or traffic emissions. In order to validate this method, a more detailed study of links between magnetic parameters characterizing the magnetic minerals and concentrations of metals is necessary. In this study, the connections between 24 metals (Pb, Cu, Zn, Co, Cd, Sb, As, Fe, Ni, Cr, Ag, Sc, Ba, Hg, Be, Bi, Mn, Al, Ti, Se, Ga, Li, V, and Mo) and five magnetic parameters (χ, χfd, SOFT, SIRM, and χARM) in Xuzhou urban topsoil have been explored and the magnetic diagnosis models for some of the metals have also been established. Our results show some metal contents could be initially estimated quantitatively by means of magnetic measurements for the Xuzhou urban topsoil.
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  Problems in the Mid-Yangtze River after the Commencement of the Three Gorges Project (TGP)

  . 2006, 24(0605): 49-54.

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  The Three Gorges Project (TGP) will bring about tremendous benefits for the mid-Yangtze River after its commencement in 2008. We should, on the other hand, also pay close attention to problems it might incidentally cause. For instance, the trapping of sediment by the TGP reservoir will cause the river downstream of the dam lose its equilibrium in sediment fluxes for a long time and bring about scours and river regime changes in the Jingjiang reach. If too much erosion take place in the Lower part of the Jingjiang reach, the flood conditions for the area around the Chenglingji reach and the Dongting Lake would be seriously affected. It seems to the author that the TGP could not have the ability to protect the said area if the main task in protecting Jingjiang reach should be ensured, since the capacity of the TGP reservoir is comparatively small. The problems for the Chenglingji and Dongting Lake should, however, be carefully studied and well settled with more measures.
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  Study of Tensile Properties of Dry Sisal Leaf and its Composite Board

  . 2006, 24(0605): 55-58.

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  In this essay, dry sisal leaf was used as reinforced material and was combined with epoxy resin to produce reinforced composite board, and the tensile properties of the composite board were studied. The study indicated that dry sisal leaf itself could be used as a kind of directional reinforced material, and the directional tensile properties of the composite board were improved greatly.
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  Detecting Anti-FcεRI Autoantibodies and its Significance

  . 2006, 24(0605): 59-61.

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  The alpha subunit ectodomain of FcεRI (αt) was successfully produced by baculovirus expression system. This recombinant protein had been utilized to detect the anti-FcεRI antoantibodies. The results showed no significant difference of the autoantibodies positive rate between the chronic urticaria group and the health control groups.
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  Method of Determining the Ratio of Single Coal in Mixed Coal

  . 2006, 24(0605): 62-65.

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  A new method that calculates the ratio of single coal in mixed coal is given. When several single coal peaks are partly overlapped, separating overlapped curve is established. The method with the characteristics of simple operation and single result is based on the integral of normal distribution equation of every single coal. It can be used in many complex problems. As calibration of vitrinite content is introduced, the exact ratio of single coal in mixed coal can be figured out. The process of establishing curve distribution equation is a good example of obtaining several parameters according to one group of test date.
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  Analysis and Application of Bottom Half Mechanism in Linux Kernel

  . 2006, 24(0605): 66-70.

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  The Bottom Half mechanism in Linux kernel is discussed in the paper for the realization of interrupt programs. Furthermore, the Bottom Half, including BH function interface, task queue, tasklet, softirq, and work queues, which were evolved from linux2.0 to linux2.6, is analyzed in detail from the two aspects of realization theory and application.
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  Design for Communication Between 3G Mobile Phone and NGN Terminal

  . 2006, 24(0605): 70-72.

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  With the development of wireless communication and NGN, the communication between 3G mobile phone and NGN terminal becomes a necessary problem to resolve. The multimedia communication protocol for 3G is 3G-324M; however, the protocol for NGN is H.323/SIP. The scheme based on soft switch to implement the multimedia communication between 3G and NGN is presented and its implement mechanism is discussed in depth.
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  A Heuristic Algorithm for Location-routing Problems with Time Windows

  . 2006, 24(0605): 72-75.

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  This paper considers a multi-depot location-routing problem with hard time windows for the customers, and capacity restrictions for the vehicles and the depots. And we propose a two-phase heuristic algorithm to solve this complex model. In the first phase, we allocate customer nodes to some appropriate depots, considering the time windows; and in the second phase, we optimize the routing problem for every depot and its related customers by improved C-W algorithm. At last, we give an analysis about this algorithm through an example.
研究报告
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  Analysis of Water Resources Demand to Develop Well-being Society

  . 2006, 24(0605): 76-79.

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  Based on the analyzing tendency of economic and social development and water resources demand, the author analysed the relationship between economic and social development with water resources utilization in China, discussed demand and guarantee capacity of water resources to develop well-being society. It is concluded that water resources can basically ensure the economic and social development, but cannot satisfy water demand for ecological environment protection in 2020.
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  Study of Horizontal Trust in Enterprise Based on Evolutionary Game

  . 2006, 24(0605): 80-82.

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  This paper builds the duplicative dynamic model of horizontal trust in enterprise under the bounded rationality. Based on the model, the paper analyzes the evolutionary trends of horizontal trust in enterprise. It is found that the incentive to truster and the punishment to trustee by changing the matrix of payoffs are two keys.
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  Study of the Relationships between Joint Mechanism of the Region Innovation Network Main-body and Region Innovation Achievements

  . 2006, 24(0605): 82-85.

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  This article discusses innovation achievements in the region innovation network by the relational capital, innovation network joint mechanism, and main-body innovation ability. Taking the high-tech development regions and Scientific and Technological Park regions in Jiangsu Province as samples, the article carries on the real diagnosis, and come to the conclusion that "the former cooperation experience, the great microscopic relations capital formation factor have been helpful in the establishment of region innovation network main body in relations, interaction, association of the same level network joint mechanism, and then the promotion of innovation achievements".
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  Research Emphasis and Reflection of Strategy for Water Saving Agriculture in China

  . 2006, 24(0605): 86-88.

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  Based on the contradiction for agricultural water in safe water-strategy and safe food-strategy of China, the authors considered the only outlet for resolving the contradiction to develop the water efficient agriculture depending on innovation of science and technology. Furthermore, the authors analyzed the general idea for developing the water efficient agriculture from strategy aspect. On the premise of no-increasing agricultural water, the authors put forward an important view for meeting food safety water demand 15 years in the future by improving utilization ratio and utilization efficiency of agricultural water. Finally, the authors suggested five of research emphases including the biological water saving technology, inferior water resources development technology, water saving irrigation technology and product, dryland water high-efficient agriculture, and the regional development mode of water saving in field for water saving agriculture.
科技评论
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  The Naissance of Animal World on the Earth:A Review of The Dawn of Animal World

  . 2006, 24(0605): 89-90.

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新技术介绍
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  Research on Network Measurement Technology

  . 2006, 24(0605): 90-93.

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  Network measurement technology is an important field in network research, and is of great meaning in both theory and practice. This paper introduces the concept, taxonomy from different points of view, and current research situations related to network measurement. It analyzes common measurement methods, tools and some hot points, addresses the main research organizations and network measurement architectures. Based on the research above, a Network Performance Measurement Infrastructure (NPMI) is presented. Finally, it gives future directions and development trend of network measurement technology.