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| 1 | Vegetation and soil carbon storage in China显示文摘This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors. | LI Kerang, WANG Shaoqiang & CAO MingkuiInstitute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to Li Kerang | 2004 | Science China Earth Sciences2004，47，1： | 60 |
| 2 | Analysis on the ecological benefits of the stream water conveyance to the dried-up river of the lower reaches of Tarim River,China显示文摘This paper analyzes the monitored data of the 4 times of stream water conveyances to the river section where the stream flow was cut-off, of 9 groundwater-monitoring sections and 18 vegetation plots in the lower reaches of Tarim River. The results show that the groundwater depth in the lower reaches of Tarim River rose from 9.87 m before the conveyances to 7.74 m and 3.79 m after the first and second conveyances, 3.61 and 3.16 m after the 2 phases of the third conveyance, and 2.66 m after the fourth conveyance. The transverse response scope of groundwater level was gradually enlarged along both sides of the channel of conveyances, i.e., from 450 m in width after the first conveyance to 1050 m after the fourth conveyance, but the response degree of groundwater level was reduced with the increase of the distance away from the channel of conveyances. The composition, distribution and growth status of the natural vegetation are directly related to the groundwater depth. The indexes of Simpson’s biodiversity, McIntosh’s evenness and Margalef’s richness, which reflect the change of the quantity of species and the degree of biodiversity, are reduced from 0.70, 0.48 and 0.90 to 0.26, 0.17 and 0.37 re- spectively along with the drawdown of groundwater level from the upper reaches to the lower reaches. After the stream water conveyances, the natural vegetation in the lower reaches is saved and restored along with the rise of groundwater level, the response scope of vegetation is gradually enlarged, i.e., from 200— 250 m in width after the first conveyance to 800 m after the fourth conveyance. However, there is still a great disparity to the objective of protecting the “Green Corridor”in the lower reaches of Tarim River. Thus, it is suggested to convey the stream water in double-channel way, combine the conveyance with water supply in surface scope, or construct the modern pipe-conveyance network systems so as to save the natural vegetation in an intensive way, achieve the efficient water consumption and speed up the restoration and re- generation of the damaged ecosystems in the lower reaches of Tarim River. | CHEN Yaning1,ZHANG Xiaolei1,ZHU Xiangmin2,LI Weihong1,ZHANG Yuanming1,XU Hailiang1,ZHANG Hongfeng1 & CHEN Yapeng1 1.Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China 2.Management Beureau od Tarim River Basin,Kurle 831102,China Correspondence should be addressed to Chen Yaning(email: cheyn@ms.xjb.ac.cn) | 2004 | Science China Earth Sciences2004，47，11： | 58 |
| 3 | Quantitative relationships between vegetation and several pollen taxa in surface soil from North China显示文摘According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept | LI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and Environmental Sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 3. School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024, China Correspondence should be addressed to Li Yiyin | 2000 | Chinese Science Bulletin2000，45，16： | 24 |
| 4 | Cellular automata pedestrian movement model considering human behavior显示文摘The pedestrian movement is more complex than vehicular flow for the reason that people are more flexible and intelligent than car. Without the limit of 搇anes?pedestrian movement is loose and free. Furthermore, they are easily affected by other walkers as well as the environ-ment around. In this paper some special technique is intro-duced considering human behavior to make the rules more reasonable. By simulating the two-dimension pedestrian movement, the phase transition phenomena of pedestrian movement, including the up walkers moving from the bottom to the upper boundary and the right walkers moving from the left to the right boundary, are presented. Studying on the effect of the system size on the critical density shows that the critical density is independent of the system size in the scope studied in this paper. | YANG Lizhong, FANG Weifeng, LI Jian, HUANG Rui & FAN Weicheng State Key Laboratory of Fire Science, University of Science and Tech-nology of China, Hefei 230026, China Correspondence should be addressed to Yang Lizhong (e-mail:zxd@ustc. edu.cn) | 2003 | Chinese Science Bulletin2003，48，16： | 16 |
| 5 | Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to Mesozoic tectonic transition显示文摘Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area. | LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. China University of Geosciences, Beijing 100083, ChinaCorrespondence should be addressed to Li Zhong (email: lizhongd@mail.igcas.ac.cn) | 2004 | Science China Earth Sciences2004，47，2： | 15 |
| 6 | Progress in research and application of water mist fire suppression technology显示文摘Water mist technology in fire suppression has been a subject of many investigations over the last decade. This paper introduces the concept of water mist technology and discusses its extinguishment mechanisms in comparison with other fire suppression systems briefly. A survey is made on the recent applications of water mist for (1) Class B spray and pool fires in machinery spaces, gas turbine enclosures, combat vehicles, and flammable liquid storage rooms; (2) Class A fires in residential occupancies, marine accommoda-tions and public spaces, heritage buildings and libraries; (3) Class C fires in electronic equipment and computer rooms; and (4) the fires in aircraft onboard cabin and cargo com-partments. The paper proceeds to review some new applica-tions of water mist for the Class K fires in commercial cook rooms. Use of water mist for total-ship protection as well as the fire protection of heavy goods vehicle shuttle trains is also investigated. At last, the up-to-date development of corresponding test to evaluate the capabilities and limitaions of water mist is discussed. | LIU Jianghong, LIAO Guangxuan, LI Peide, FAN Weicheng & LU Qiang State Key Laboratory of fire Science, University of Science and Tech-nology of China, Hefei 230026, China Correspondence should be addressed to Liu Jianghong (e-mail: ljh@ ustc.edu.cn) | 2003 | Chinese Science Bulletin2003，48，8： | 15 |
| 7 | Functional analysis of the larval serum protein gene promoter from silkworm,Bombyx mori.显示文摘The regulation region of larval serum protein gene, Bombyx mori. (BmLSP), consisting of the first intron, the first exon, the central promoter region and 5′-upstream region, is cloned from genomic DNA from the silkworm va-riety of Suju譓inghu. Using PCR and restriction endonu-clease methods, a series of luciferase reporter plasmids, driven by different length of BmLSP promoters, are con-structed. Via the transient expression system in BmN cells, the effects of the regulation elements and foreign insect hor-mones on the BmLSP promoter activity are investigated. The results demonstrate that the promoter activity of BmLSP is 5.8- or 4.4-fold higher than that of BmLSPs whose first in-tron or the element in 5′-upstream region harboring the homologous sequence with the first intron of light-chain fib-roin gene (EHIF) is deleted, respectively, suggesting that both the first intron and EHIF contain the main positive cis-acting elements. However, the inactive mariner transposable ele-ment (MTE) in 5′-upstream region presents a negative effect. Furthermore, the effects of juvenile hormone analogue (JHA) on the BmLSP promoter activity show a typical dose-dependent manner, that is, low concentration treat-ments increase the BmLSP promoter activity and high con-centration treatments decrease it. Meanwhile, insect ecdy-sone (MH) treatments present no significant effect. | TANG Shunming, YI Yongzhu, SHEN Xingjia, ZHANG Zhifang, LI Yiren & HE Jialu Key Laboratory of Silkworm Biotechnology, Ministry of Agriculture, Sericultural Research Institute, Chinese Academy of Agricultural Sci-ences, Zhenjiang 212018, China Correspondence should be addressed to Zhang Zhifang (e-mail: zjsbsri@ public.zj.js.cn) | 2003 | Chinese Science Bulletin2003，48，23： | 13 |
| 8 | Molecular characterization of Tomato yellow leaf curl China virus and its satellite DNA isolated from tobacco显示文摘Virus isolates, Y8, Y36 and Y38, were obtained from tobacco plants showing leaf curl symptoms in Honghe, Yunnan Province. In reactions with 14 monoclonal antibod-ies raised against Begomovirus particles, Y8, Y36 and Y38had similar antigenic reaction in TAS-ELISA as Tomato yel-low leaf curl China virus (TYLCCNV). The complete DNA-A nucleotide sequences of Y8, Y36 and Y38 were determinedand they contain 2727, 2730 and 2730 nucleotides, respec-tively. Each of the DNA-A sequences has a typical Bego-movirus genome organization encoding 6 ORFs with 2 ORFs [AV1(CP) and AV2] in virion-sense DNA and 4 ORFs (AC1to AC4) in complementary-sense DNA. Comparisons withtotal DNA-A, intergenic region and deduced amino acid se-quences of individual ORFs show that Y8, Y36 and Y38 are isolates of TYLCCNV. Satellite DNA molecules (DNAb) were found to be associated with Y8, Y36 and Y38, which consist of 1338, 1339 and 1338 nucleotides, respectively. Compari-sons show that these DNAb molecules share 98%—99% se-quence identities on nucleotide level and have a commonORF (designated C1) encoding 126 amino acids on the com-plementary strand. | XIE Yan, ZHOU Xueping & LI Guixin Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China Correspondence should be addressed to Zhou Xueping (e-mail: zzhou@zju.edu.cn) | 2003 | Chinese Science Bulletin2003，48，8： | 13 |
| 9 | Over-expression of an Arabi-dopsisd δ-OAT gene enhances salt and drought tolerance in transgenic rice显示文摘d-OAT, ornithine--aminotransferase, is the key enzyme involved in proline biosynthesis. In this study the Arabidopsis d -OAT gene was transferred into rice (Oryza sativa L. ssp japonica cv. Zhongzuo 321), whose successful integration was demonstrated by PCR and Southern blot analysis. The over-expression of the gene in transgenic rice was also confirmed. Biochemical analysis showed that, under salt or drought stress conditions, proline contents in the leaves and roots in transgenic rice plants were 5- to 15-fold of those in non-transgenic controls. Under stress conditions, germinating rate of transgenic lines is higher than that of controls. Although the growth of rice plants tested were more and more retarded with the increasing of NaCl concentration, the transgenic plants grow faster compared to the controls under the same stress condition. Meanwhile, the resistance to KCl and MgSO4 stresses was also found enhanced in trans-genic rice. Furthermore, the over-expression of d -OAT also improved the yield of transgenic plants under stress condi-tions. The average yield per plant of transgenic lines in-creases about 12%—41% more than that of control lines under 0.1 mol/L NaCl stress. These data indicated that the over-expression of d -OAT, with the accumulation of proline, resulted in the enhancement of salt and drought tolerance and an increase of rice yield, which is of significance in agri-culture. | WU Liangqi, FAN Zhanmin, GUO Lei, LI Yongqing, ZHANG Wenjing, QU Li-Jia & CHEN Zhangliang The National Laboratory of Protein Engineering and Plant Genetic En-gineering, College of Life Sciences, Peking University, Beijing 100871, China Correspondence should be addressed to Qu Li-Jia (e-mail: qulj@pku. edu.cn) | 2003 | Chinese Science Bulletin2003，48，23： | 11 |
| 10 | Four kinds of ENU-induced white spot mice and chromosome locations of the mutant genes显示文摘Phenotype-driven is the name for an ap-proach used to study gene functions through mutagenesis, location and cloning of the mutant gene. In this study, 150 male C57BL/6J(B6) mice were treated with ENU and repro-duced a total offspring of 3860. Of these descendants, 210 exhibited mutation phenotypes by screening, and more than 10 of them are hereditable. Four kinds of mutant mice, named Wbct, W-1Bao, W-2Bao, and W-3Bao, showed dominant hereditary white spot mutation with partial albinism on their belly, distal limbs and tail terminal. To map these mutant genes, 39 microsatellites, equally distributed on the mouse genome and with difference between B6 and DBA/2J (D2), were selected to scan the genome after discrimination of the white spots in the F2 mice [(B6×D2)×D2]. It is found that, the log odds score (LODS) between W-1Bao and D5Mit168 is 0.56, and the LODS of W-1Bao and D5Mit352 is 4.47. With the gradual application of microsatellites D5Mit290, D5Mit312, D5Mit308 and D5Mit356 that are close to the mutant gene, and the number of F2 mice going up to 537, the mutant W-1Bao is located between D5Mit356 and D5Mit308 on chro-mosome 5, about 42.19 cM from the centromere. In the same way, W-2Bao and W-3Bao are mapped nearby W-1Bao, and Wbct is located on chromosome 1, about 41.6 cM from the centro-mere. After searching for the mouse genome database (MGD) and performing a one-by-one study of all genes located on chromosome subregion, it is believed that the kit gene is an excellent candidate for the white spot mutations of W-1Bao, W-2Bao and W-3Bao. | WU Baojin1,2, MAO Huihua1, SHAO Yixiang1, XUE Zhengfeng1 & LI Houda1 1. Comparative Medicine Center of Yangzhou University, Yangzhou 225009, China 2. Medical College of Yangzhou University, Yangzhou 225001, China Correspondence should be addressed to Li Houda (e-mail: houdali @yahoo.com.cn) | 2003 | Chinese Science Bulletin2003，48，24： | 11 |
| 11 | Friction of Alloys at High Temperature显示文摘A brief review is given about the friction and wear properties of high temperature alloys. Above a critical temperature, if the oxide becomes ductile, it will flow over the surface and prevent metal-to-metat contact. In order to study the tribology of oxide lubrication. a series of tests were carried out using Cu(ReO4)2 as a lubricant. The effects of time. Surface finish. substrates. load and temperature were investigated. A mechanism of lubrication is proposed in which the surface slip predominates along with mechanical attachment of oxide to the surface. | M.B.Peterson (Wear Sciences, 925 Mallard Circle, Arnold Maryland 21012, USA)(To whom correspondence should be addressed)S.J.Calabrese (Rensselaer Polytechnic Institute, Troy, NY, USA)Shizhuo LI and Xiaoxia JIANG (Institute of Metal Research, Chinese Acad | 1994 | Journal of Materials Science & Technology1994，10，5： | 11 |
| 12 | Optimal decision-making model of spatial sampling for survey of China's land with remotely sensed data显示文摘In the remote sensing survey of the country land, cost and accuracy are a pair of conflicts, for which spatial sampling is a preferable solution with the aim of an optimal balance between economic input and accuracy of results, or in other words, acquirement of higher ac-curacy at less cost. Counter to drawbacks of previous application models, e.g. lack of compre-hensive and quantitative-comparison, the optimal decision-making model of spatial sampling is proposed. This model first acquires the possible accuracy-cost diagrams of multiple schemes through initial spatial exploration, then regresses them and standardizes them into a unified ref-erence frame, and finally produces the relatively optimal sampling scheme by using the discrete decision-making function (built by this paper) and comparing them in combination with the dia-grams. According to the test result in the survey of the arable land using remotely sensed data, the Sandwich model, while applied in the survey of the thin-feature and cultivated land areas with aerial photos, can better realize the goal of the best balance between investment and accuracy. With this case and other cases, it is shown that the optimal decision-making model of spatial sampling is a good choice in the survey of the farm areas using remote sensing, with its distin-guished benefit of higher precision at less cost or vice versa. In order to extensively apply the model in the surveys of natural resources, including arable farm areas, this paper proposes the prototype of development using the component technology, that could considerably improve the analysis efficiency by insetting program components within the software environment of GIS and RS. | LI Lianfa1,2, WANG Jinfeng1 & LIU Jiyuan1 1. Institute of Geographic Sciences & Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. Department of Intelligence Science, Peking University, Beijing 100087, China Correspondence should be addressed to Li Lianfa | 2005 | Science China Earth Sciences2005，48，6： | 10 |
| 13 | Benthic foraminifera and bottom water evolution in themiddle-southern Okinawa Trough during the last 18 ka显示文摘A piston sediment core E017 from the middle-southern Okinawa Trough was investigated. A preliminary study of the deep-water evolution since 18 cal. ka BP was performed basedon the quantitative census data of benthic foraminiferal fauna, together with planktonic foraminiferal oxygen and carbon isotope, AMS14C dating, and the previous results achieved in thesouthern Okinawa Trough. The result shows that the benthic fauna was dominated by Buliminaaculeata (d′Orbigny), Uvigerina peregrina (Cushman), Hispid Uvigerina and Uvigerina dirupta(Todd) during the glaciation-deglaciation before 9.2 cal. ka BP, while Epistominella exigua(Brady), Pullenia bulloides (d′Orbigny), Cibicidoides hyalina (Hofker), Sphaeroidina bulloides(d’Orbigny) and Globocassidulina subglobosa (Brady) predominated the fauna in the post-glaciaperiod after 9.2 cal. ka BP. The benthic foraminifera accumulation rate (BFAR), paleoproductivityestimates and benthic foraminiferal assemblage conformably indicate that surface water paleoproductivity and organic matter flux during the glaciation-deglaciation were higher than those othe post-glacial period in the middle-southern Okinawa Trough, and gradually enhanced from thesouthern to the central Okinawa Trough during the glaciation-deglaciation, which could becaused by the discrepancy of the terrigenous nutrients supply. High abundances of E. exigua, anindicator of pulsed organic matter input, after 9.2 cal. ka BP may indicate that the intensity oseasonally riverine pulsed flux during the post-glacial period was stronger than that of the glaciation-deglaciation period, and the seasonal influx in the central trough might be stronger than inthe south. The temporal distributions of the typical species indicating bottom water oxygen content and ventilation condition show that the ventilation of the bottom water during the post-glaciaperiod is more active than the glaciation-deglaciation, which reflects that the evolution of the intermediate and deep waters of the northwestern Pacific during the last glaciation has no evideninfluence on the deep-water of the middle-southern Okinawa Trough. Additionally, the variationsin agglutinated benthic foraminiferal abundance and other carbonate dissolution proxies indicatethat carbonate dissolution gradually increased since the last 18 ka in the Okinawa Trough andrapidly enhanced at 9.2 cal. ka BP. The modern shallow carbonate lysocline could form at 3 calka BP. | LI Tiegang1, XIANG Rong1,2, SUN Rongtao1 & CAO Qiyuan1 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China 2. College of Geosciences, Ocean University of China, Qingdao 266003, China Correspondence should be addressed to Li Tiegang | 2005 | Science China Earth Sciences2005，48，6： | 9 |
| 14 | The input/removal rates of size-fractionated ^210Po in the Jiulongjiang estuary and its implications显示文摘The geochemical behaviors of dissolved (<0.4 mm), low molecular weight (<10 kDa) and colloidal (10 kDa- 0.4 mm) 210Po in surface waters from the Jiulongjiang estuary were examined and the input/removal rates of different 210Po species were estimated. Both dissolved and low molecular weight 210Po were considerably removed during estuarine mixing. However, colloidal 210Po was removed only at low salinity regions (S <15) but had input behavior at high salin-ity surface waters (S >15). The input/removal rates of three species indicate that 210Po was removed rapidly in the Jiu-longjiang estuary. The discrepancy of input/removal rates between 210Po species suggests different geochemical be-havior and a dynamic transformation between 210Po species. Low molecular weight 210Po may be more appropriate for characterizing the 210Po behavior in estuary zone than the traditional dissolved 210Po. | YANG Weifeng, CHEN Min, HUANG Yipu, QIU Yusheng, ZHANG Lei, XING Na & LI Yanping Department of Oceanography, Xiamen University, Xiamen 361005, China Correspondence should be addressed to Huang Yipu (e-mail: yphuang@ jingxina.xmu.edu.cn) | 2003 | Chinese Science Bulletin2003，48，21： | 8 |
| 15 | Identification and expression profiling of putative odorant-binding proteins in the malaria mosquitoes, Anopheles gambiae and A. arabiensis显示文摘Olfaction plays a major role in host-seeking behaviour of mosquitoes. An informat- ics-based genome-wide analysis of odorant-binding protein (OBP) homologues is under- taken, and 32 putative OBP genes in total in the whole genome sequences of Anopheles gam- biae are identified. Tissue-specific expression patterns of all A. gambiae OBP candidates are determined by semi-quantitative Reverse Transcription (RT)-PCR using mosquito actin gene a internal expression control standard. The results showed that 20 OBP candidates had strong expression in mosquito olfactory tissues (female antennae), which indicate that OBPs may play an important role in regulating mosquito olfactory behaviours. Species-specific expression pat- terns of all putative anopheline OBPs are also studied in two of the most important malaria vec- tors in A. gambiae complex, i.e. A. gambiae and A. arabiensis, which found 12 of the putative OBP genes examined displayed species-differential expression patterns. The cumulative relative expression intensity of the OBPs in A. arabiensis antennae was higher than that in A. gambiae (the ratio is 1441.45:1314.12), which might be due to their different host preference behaviour. While A. gambiae is a highly anthropophilic mosquito, A. arabiensis is more opportunistic (Vary- ing from anthropophilic to zoophilic). So the latter should need more OBPs to support its host selection preference. Identification of mosquito OBPs and verification of their tissue- and spe- cies-specific expression patterns represent the first step towards further molecular analysis of mosquito olfactory mechanism, such as recombinant expression and ligand identification. | LI Zhengxi1,Jing-Jiang ZHOU2,SHEN Zuorui1 & Lin FIELD2 1.Department of Entomology,China Agricultural Univeristy,Beijing 100094,China 2.Biological Chemistry Division, Rothamsted Research,Harpenden, Herts. AL5 2JQ, UK Correspondence should be addressed to Li Zhengxi | 2004 | Science China(Life Sciences)2004，47，6： | 7 |
| 16 | Physiological responses of osteoblasts to cyclic stretching and the change of intracellular calcium concentration显示文摘The development of bone tissues is regulated by mechanical stimulation. Cyclic stretching was applied to the osteoblasts that were delivered from rat calvarie. The results showed that stretching at 500 me increased the cell prolifera-tion while loading at 1000 me and 1500 me inhabited cell growth. Loading also increased the adhesive force between cells and substrate as well as spreading areas of osteobalsts. Furthermore, the fluorescence probe Fluo-3/AM was used to investigate the effect of stretching stimulation on the intra-cellular calcium concentration of osteoblasts. The intracellu-lar calcium concentration of osteoblasts that were stretched at 500 me for 5 min was 92.9% higher than the control. After being treated with the panax ontoginseng saponins, the stretched osteoblasts still expressed 28.6% higher intracellu-lar calcium concentration than that of the control, which proved that both the influx of extracellular calcium and the release of intracellular calcium store were involved in the increase of intracellular calcium concentration when os-teoblasts responded to the cyclic stretching. And the influx of extracellular calcium through transmembrance channel played a main role. | TANG Liling, WANG Yuanliang, GU Li, CAI Shaoxi & SU Aihua Bio-engineering College, Chongqing University, Chongqing 400044, China Correspondence should be addressed to Tang Liling | 2003 | Chinese Science Bulletin2003，48，4： | 7 |
| 17 | A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation显示文摘Recrystallized grains, less than 200 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high purity aluminum by ECAE at ambient temperature. The experimental results showed that high strain rate and large deformation could induce dynamic recrystallization.Based on dislocation dynamics and grain orientation change enhanced by plastic deformation,a model for the recrystallization process is developed. The model is used to explain the ultra fine grains which are formed at a temperature still much lower than that for the conventional | Qiang LI and Yongbo XU(State Key Laboratory for Fatigue and Fracture of Materials, Institute of Metal Research, Chinese Academy of Sciences,Shenyang 110015, China) To whom correspondence should be addressed Present address: Analysis Cener, School of Mater | 1999 | Journal of Materials Science & Technology1999，15，5： | 7 |
| 18 | Population information extraction in Chaohu watershed based on RS and GIS显示文摘It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed. | LIU Jianjun1,2 & LI Chunlai3 1. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100039, China 3. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ hotmail.com) | 2003 | Chinese Science Bulletin2003，48，2： | 6 |
| 19 | Preparation of graphitic carbon nitride by electrodeposition显示文摘The CNx thin film was deposited on Si(100) substrate from a saturated acetone solution of cyanuric tri-chloride and melamine (cyanuric trichloride/melamine=1︰1.5) at room temperature. X-ray diffraction (XRD) results showed that the diffraction peaks in the pattern coincided well with those of graphite-like carbon nitride calculated in the literature. The lattice constants (a=4.79 ? c=6.90 ) for g-C3N4 matched with those of ab initio calculations (a=4.74 ? c=6.72 ? quite well. X-ray photoelectron spectroscopy (XPS) measurements indicated that the elements in the de-posited films were mostly of C and N (N/C=0.75), and N (400.00 eV) bonded with C (287.72 eV) in the form of six-member C3N3 ring. The peaks at 800 cm-1, 1310 cm-1 and 1610 cm-1 in the Fourier transform infrared (FTIR) spec-trum indicated that triazine ring existed in the product. These results demonstrated that crystalline g-C3N4 was ob-tained in the CNx film. | LI Chao1,2, CAO Chuanbao1 & ZHU Hesun1 1. Research Center of Materials Science, Beijing Institute of Technology, Beijing 100081, China 2. Department of Chemical Engineering, Zhengzhou Institute of Light Industry, Zhengzhou 450002 China Correspondence should be addressed to Cao Chuanbao | 2003 | Chinese Science Bulletin2003，48，16： | 6 |
| 20 | The complete mitochondrial genomes sequences of Asio flammeus and Asio otus and comparative analysis显示文摘The complete mitochondrial genomes of Asio flammeus and Asio otus were se- quenced and found to span 18858 bp and 18493 bp, respectively. It is surprising to find the for- mer to be the largest among all avian mitochondrial genomes sequenced so far. The two ge- nomes have very similar gene order with that of Gallus gallus, neither contains the pseudo con- trol region, but both have a single extra base, namely Cytidine, at position 174 in ND3 gene. The control regions of Asio flammeus and Asio otus’ mitochondrial genomes span 3288 bp and 2926 bp respectively, which are the longest among vertebrates except for Myxine glutinosa and con- tribute to the large size of two genomes. The 3′end of the control region of Asio flammeus and Asio otus contains many tandemly repeated sequences, which are highly similar to a putative control element, i.e. Mt5, and may form stable stem-loop secondary structures. Such repeated sequences probably play an important role in regulating transcription and replication of mito- chondrial genome. Our results may provide important clues for uncovering the origin and evolu- tion mechanisms of mitochondrion genome. | SUN Yi1, MA Fei1, XIAO Bing1, ZHENG Junjie2, YUAN Xiaodong2, TANG Minqian2, WANG Li3, YU Yefei3 & Li Qingwei1 1. College of Life Sciences, Liaoning Normal University, Dalian 116029, China 2. TaKaRa Biotechnology (Dalian) Co., Ltd., Dalian 116600, China 3. The Administrative Office of the Natural Protective Zone of Snake Island-Lao Tie Hill, Dalian 116041, China Correspondence should be addressed to Li Qingwei | 2004 | Science China(Life Sciences)2004，47，6： | 6 |
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