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| 1 | Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)显示文摘In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species. | WAN FangHao1, LIU WanXue1, GUO JianYing1, QIANG Sheng2, LI BaoPing2, WANG JinJun3, YANG GuoQing1, NIU HongBang1, GUI FuRong1, HUANG WenKun1, JIANG ZhiLin1 & WANG WenQi3 1State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China 2College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China 3Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, China | 2010 | Science China(Life Sciences)2010，53，11： | 42 |
| 2 | Telomere erosion is independent of microsatellite instability but related to loss of heterozygosity in gastric cancer显示文摘AIM To correlate the length of the telomere to microsatellite instability (MSI) and loss of heterozygosity (LOH) of APC, MCC and DCC genes in gastric carcinomas.METHODS Telomeric restriction fragment (TRF) length of gastric cancer was measured with Southern blot. LOH of APC, MCC and DCC genes, microsatellite instability (MSI) and frameshift mutation of hMSH6, TGF-βR Ⅱ and BAX genes were analyzed by PCR-based methods.RESULTS Sixty-eight cases of sporadic gastric carcinoma were studied for MSI using five microsatellite markers. MSI in at least one locus was detected in 17 (25%) of 68 tumors analyzed. Frameshift mutations of hMSH6, TGF-βR Ⅱ and BAX were detected in 2,6 and 3 of gastric carcinomas respectively showing high MSI (≥ 2 loci, n = 8), but none was found in those showing Iow MSI (only one locus, n = 9) or MSS (tumor lacking MSI or stable, n = 51). Thirty-five cases, including all high MSI and Iow MSl, were studied for TRF. The mean TRF length was not correlated with clinicopathological parameters.No association was observed between TRF length and MSI or frameshift mutation. On the contrary, LOH at the DCC locus was related to telomere shortening (P< 0.01). This tendency was also observed in APC and MCC genes,although there was no statistical significance.CONCLUSION The development of gastric cancer can arise through two different genetic pathways. In high MSI gastric cancers, defective mismatch repair allows mutations to accumulate and generate the high MSI phenotype. In gastric cancers showing either Iow MSI or MSS, multiple deletions may represent the LOH pathway.Telomere erosion is independent of high MSI phenotype but related to the LOH pathway in gastric cancer. | Dian-Chun Fang Shi-Ming Yang Xiao-Dong Zhou Dong-Xu Wang Yuan-Hui Luo Department of Gastroenterology,Southwest Hospital,Third Military Medical University,Chongqing 400038,China | 2001 | World Journal of Gastroenterology2001，7，4： | 35 |
| 3 | Assessment of candidate plant DNA barcodes using the Rutaceae family显示文摘DNA barcoding is a rapidly developing frontier technology that is gaining worldwide attention.Here,seven regions (psbA-trnH,matK,ycf5,rpoC1,rbcL,ITS2,and ITS) with potential for use as DNA barcodes were tested for their ability to identify 300 samples of 192 species from 72 genera of the family Rutaceae.To evaluate each barcode’s utility for species authentication,PCR amplification efficiency,genetic divergence,and barcoding gaps were assessed.We found that the ITS2 region exhibited the highest inter-specific divergence,and that this was significantly higher than the intra-specific variation in the 'DNA barcoding gap' assessment and Wilcoxon two-sample tests.The ITS2 locus had the highest identification efficiency among all tested regions.In a previous study,we found that ITS2 was able to discriminate a wide range of plant taxa,and here we confirmed that ITS2 was also able to discriminate a number of closely related species.Therefore,we propose that ITS2 is a promising candidate barcode for plant species identification. | LUO Kun1,2,CHEN ShiLin1,CHEN KeLi2,SONG JingYuan1,YAO Hui1,MA XinYe1,ZHU YingJie3,PANG XiaoHui1,YU Hua1,LI XiWen1,4 & LIU Zhen2 1Institute of Medicinal Plant Development,Peking Union Medical College,Chinese Academy of Medical Sciences,Beijing 100193,China 2College of Pharmacy,Hubei University of Chinese Medicine,Wuhan 430061,China 3School of Bioscience and Engineering,Southwest Jiaotong University,Chengdu 610031,China 4Department of Chemistry,Tsinghua University,Beijing 100084,China | 2010 | Science China(Life Sciences)2010，53，6： | 32 |
| 4 | 论信息系统集成的实施显示文摘本文以笔者从事信息系统集成的经验为基础,讨论了信息系统集成的内涵、实施信息系统集成的三种模式及其利弊、适用场合。 | Zeng Huashen College of Computer & Comun Engi ,Southwest Jiaotong Univ.,Sichuan·Chengdu 610031 | 1997 | 计算机应用1997，17，2： | 32 |
| 5 | Mutation analysis of APC gene in gastric cancer with microsatellite instability显示文摘AIM: To evaluate the role of APC mutation in gastric carcinogenesis and to correlate APC mutation with microsatellite instability (MSI) in gastric carcinomas. METHODS: APC mutation was measured with multiplex PCR, denaturing gradient gel electrophoresis and DNA sequencing; and MSI was analyzed by PCR-based methods.RESULTS: Sixty-eight cases of sporadic gastric carcinoma were studied for APC mutation at exon 15 and MSI. APC mutaions were detected in 15(22.1%) gastric cancers. Frequence of APC mutation (33.3 %) in intestinal type of gastric cancer was significantly higher than that in diffuse type (13.1 %, P<0.05).On the contrary, no association was observed betweerAPC mutation and tumor size,differentiation, depth of invasion, metastasis or clinical stages.Using five microsatellite markers, MSI in at least one locus was detected in 17 of 68 (25 %) of the tumors analyzed.APC mutations were all detected in MSI-L (only one locus,n=9) or MSS(tumor lacking MSI or stable, n=51), but no mutation was found in MSI-H (≥2 loci, n=8).CONCLUSION: APC mutation is involved in carcinogenesis of intestinal type of gastric cancer and is independent of MSI phenotype but related to the LOH pathway in gastric cancer. | Dian-Chun Fang Yuan-Hui Luo Shi-Ming Yang Xiao-An Li Xian-Long Ling Li Fang Department of Gastroenterology,Southwest Hospital,Third Military Medical University,Chongqing 400038,China | 2002 | World Journal of Gastroenterology2002，8，5： | 34 |
| 6 | Endoscopic patterns of gastric mucosa and its clinicopathological significance显示文摘AIM: To explore the correlation of magnifying endoscopic patterns and histopathology, Helicobacter pylori (H pylori) infection of the gastric mucosa.METHODS: Gastric mucosal patterns in 140 patients with chronic gastritis were studied using Olympus GIF-Q240Z magnifying endoscope. Histopathological examination, rapid urease test and Warrthin-Starry staining were taken with biopsy samples from the magnified sites of stomach. The magnifying endoscopic patterns were compared with histopathological results and H pylori detection.RESULTS: The pit patterns of gastric mucosa were classified as types A (round spot), B (short rod), C (branched), D (reticular) and E (villus). The detection rate of chronic atrophic gastritis (CAG) by magnifying endoscopy was 94.3 % (33/35),which was significantly higher than that by routine endoscopy (22.9 %, 8/35) (P<0.01). The pit patterns of 31 cases of intestinal metaplasia (IM) appeared as type E in 18 cases (58.1%), type D in 8 cases (25.8 %) and type C in 5 cases (16.1%). Fourteen out of 18 patients (77.8 %) with complete type (type Ⅰ) of IM appeared as type E of pit patterns, whereas only 4 of 13 (30.8 %) patients with incomplete type (types Ⅱ and Ⅲ) of IM appeared as type E (P<0.05). Collecting venules in the anterior of lower part of gastric corpus were subgrouped into types R (regular), I (irregular) and D (disappeared).H pyloriinfection was found in 12.2 %(9/74),60 %(9/15) and 84.3 %(43/51) cases in these types respectively. H pyloriinfection rate in type R was significantly lower than that in other two types (P<0.01).CONCLUSION: Magnifying endoscopy may have an obvious value in diagnosing chronic atrophic gastritis, intestinal metaplasia and H pylori infection. | Jian-Min Yang Lei Chen Yu-Lin Fan Xiang-Hong Li Xin Yu Dian-Chun Fang, Gastroenterology Research Center, Southwest Hospital, Third Military Medical University, Chongqing 400038, China | 2003 | World Journal of Gastroenterology2003，9，11： | 28 |
| 7 | Hepatitis C virus infection of human hepatoma cell line 7721 in vitro显示文摘AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro. | Zhi-Qiang Song~1 Fei Hao~1 Feng Min~2 Qiao-Yu Ma~2 Guo-Dong Liu~2 Department of Dermatology~1Department of Infectious Diseases~2,Southwest Hospital,Third Military Medical University,Chongqing 400038,China | 2001 | World Journal of Gastroenterology2001，7，5： | 26 |
| 8 | The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor显示文摘The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 107 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91% to 97% of COD were removed at up to about 3.9 g COD/(L·d) of COD volumetric loading rate. More than 97% to 100% of nitrite was denitrified at up to about 0.8 g NO -2-N/(L·d), which is 16 times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05 gN/(L·d)). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 15 days with sludge from the reactor showed that 100% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 15% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis. | ZHANG Dai-jun 1,2 (1. Department of Environmental Science, Chongqing University, Campus A, Chongqing 400044, China 2. Key Laboratory for the Southwest China Resources Exploitation and Environmental Disaster Control Engineering, Ministry of Education, China.) | 2003 | Journal of Environmental Sciences2003，15，3： | 26 |
| 9 | Effect of 5-Aza-2'-deoxycytidine on the P16 tumor suppressor gene in hepatocellular carcinoma cell line HepG2显示文摘INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20]. | Li Hua Liu1 Wen Hua Xiao2 Wei Wen Liu3 1Department of Oncology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China (now working in Department of Gastroenterology, General Hospital of PLA, Lanzhou 730050, Gansu Province, China)2Department of Oncology3Department of Gastroenterology, Southwest Hospital, Third Military Medical University, Chongqing 400038, China | 2001 | World Journal of Gastroenterology2001，7，1： | 21 |
| 10 | Mutation and methylation of hMLH1 in gastric carcinomas with microsatellite instability显示文摘AIM: To appraise the correlation of mutation and methylation of hMSH1 with microsatellite instability (MSI) in gastric cancers.METHODS: Mutation of hMLH1 was detected by Twodimensional electrophoresis (Two-D) and DNA sequencing;Methylation of hMLH1 promoter was measured with methylation-specific PCR; MST was analyzed by PCR-basecl methods.RESULTS: Sixty-eight cases of sporadic gastric carcinoma were studied for mutation and methylation of hMLH1 promoter and MSI. Three mutations were found, two of them were caused by a single bp substitution and one was caused by a 2 bp substitution, which displayed similar Two-D band pattern.Methylation of hMLH1 promoter was detected in 11(16.2%)gastric cancer. By using five MSI markers, MSI in at least one locus was detected in 17/68(25 %) of the tumors analyzed.Three hMLH1 mutations were all detected in MSI-H (≥2 loci,n=8), but no mutation was found in MSI-L (only one locus,n=9) or MSS (tumor lacking MSI or stable, n=51). Methylation frequency of hMLH1 in MSI-H (87.5 %, 7/8) was significantly higher than that in MSI-L (11.1%, 1/9) or MSS (5.9%, 3/51)(P<0.01-0.001), but no difference was found between MSI-L and MSS (P>0.05).CONCLUSION: Both mutation and methylation of hMLH1are involved in the MSI pathway but not related to the LOH pathway in gastric carcinogenesis. | Dian-Chun Fang Rong-Quan Wang Shi-Ming Yang Jian-Ming Yang Hai-Feng Liu Gui-Yong Peng Tian-Li Xiao Yuan-Hui Luo Department of Gastroenterology,Southwest Hospital,Third Military Medical University,Chongqing,400038,China | 2003 | World Journal of Gastroenterology2003，9，4： | 20 |
| 11 | On linking climate to Chinese dynastic change: Spatial and temporal variations of monsoonal rain显示文摘The causal correlation or linkage between the East Asian Monsoon (EAM) intensity and rise/fall of Chinese dynasties recently proposed by high-resolution paleoclimate reconstructions is examined in detail. Aside from many exceptions to the correlation, both instrumental and historical climate records show strong spatial variations of rainfall on annual-to-decadal scales over eastern China. The relationship between rainfall and EAM intensity also exhibits regional disparity. These observations suggest: (1) Tak-ing paleo-proxy records from a single locality in eastern China to imply changes in drought/wetness as to affect the cultural and political history of China is fraught with uncertainty. (2) On annual-to-decadal scales, the thesis that δ18O in speleothems can be used as a proxy for the EAM strength lacks empirical underpinnings. | ZHANG DeEr1, LI Hong-Chun2,3, KU Teh-Lung2,4 & LU LongHua5 1 National Climate Center, Beijing 100081, China 2 Department of Earth Sciences & Research Center of Ocean Environment and Technology, Cheng-Kung University, Tainan 70101, Taiwan, China 3 School of Geographical Sciences, Southwest University of China, Chongqing 400715, China 4 Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, USA 5 Chinese Academy of Meteorological Sciences, Beijing 100081, China | 2010 | Chinese Science Bulletin2010，55，1： | 19 |
| 12 | Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest China显示文摘As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,China. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt. | TANG LiangJie1,2,3,YANG KeMing4,JIN WenZheng1,2,3,L ZhiZhou4 & YU YiXin1,2,3 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Key Laboratory for Hydrocarbon Accumulation Mechanism,China University of Petroleum,Ministry of Education,Beijing 102249,China 3 Basin and Reservoir Research Center,China University of Petroleum,Beijing 102249,China 4 Southwest Division Company,SINOPEC,Chengdu 610081,China | 2008 | Science China Earth Sciences2008，51，S2： | 18 |
| 13 | Combining Ridge with No-Tillage in Lowland Rice-Based Cropping System: Long-Term Effect on Soil and Rice Yield显示文摘A tillage method of combining ridge with no-tillage (RNT) was employed in lowland rice-based cropping system to study the long-term effects of RNT on soil profile pattern, soil water stable aggregate distribution, nutrients stratification and yields of rice and post-rice crops. After flooded paddy field (FPF) was practiced with RNT for a long time, soil profile changed from G to A-P-G, and horizon G was shifted to a deeper position in the profile. Also the proportion of macroaggregate (> 2 mm) increased, whereas the proportion of silt and clay (< 0.053 mm) decreased under RNT, indicating a better soil structure that will prevent erosion. RNT helped to control leaching and significantly improved total N, P, K and organic matter in soil. The highest crop yields were found under RNT system every year, and total crop yields were higher under conventional paddy-upland rotation tillage (CR) than under FPF, except in 2003 and 2006 when serious drought occurred. RNT was proven to be a better tillage method for lowland rice-based cropping system. | JIANG Xian-Jun2 and XIE De-Ti College of Resources and Environment, Southwest University, 216 Tiansheng Road, Beibei, Chongqing 400716 (China) | 2009 | Pedosphere2009，19，4： | 17 |
| 14 | An isoperimetric deficit upper bound of the convex domain in a surface of constant curvature显示文摘In this paper,we give a reverse analog of the Bonnesen-style inequality of a convex domain in the surface X of constant curvature,that is,an isoperimetric deficit upper bound of the convex domain in X.The result is an analogue of the known Bottema's result of 1933 in the Euclidean plane E2. | LI Ming & ZHOU JiaZu School of Mathematics and Statistics,Southwest University,Chongqing 400715,China | 2010 | Science China Mathematics2010，53，8： | 17 |
| 15 | Heavy Metal Runoff in Relation to Soil Characteristics显示文摘Cu, Zn, Pb and Hg runoff from yellow limestone soil and purple soils and the relationships between the mobility of the heavy metals and the soil characteristics were studied in laboratory using a rainfall simulator. The results showed that the concentrations of soluble Zn in surface runoff were significantly negatively correlated with the contents of <0.002 mm particles and CEC of the soils, indicating that Zn was mostly adsorbed by clays in the soils. The contents of Cu and Hg in surface runoff were positively related to their contents in the soils. The amounts of Cu, Zn, Pb and Hg removed by surface runoff were influenced by the amounts of soil and water losses and their contents in the soils, and were closely related to the contents of soil particles 1-0.02 mm in size. | ZHAO XIULAN, QING CHANGLE and WEI SHIQIANG College Of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (china) | 2001 | Pedosphere2001，11，2： | 16 |
| 16 | Characterization of mitochondrial genome of Chinese wild mulberry silkworm, Bomyx mandarina(Lepidoptera:Bombycidae)显示文摘The complete mitochondrial genome of Chinese Bombyx mandarina(ChBm) was determined.The cir-cular genome is 15682 bp long, and contains a typical gene complement, order, and arrangement iden-tical to that of Bombyx mori(B.mori) and Japanese Bombyx mandarina(JaBm) except for two addi-tional tRNA-like structures:tRNASer(TGA)-like and tRNAIle(TAT)-like.All protein-coding sequences are initi-ated with a typical ATN codon except for the COI gene, which has a 4-bp TTAG putative initiator codon.Eleven of 13 protein-coding genes(PCGs) have a complete termination codon(all TAA), but the re-maining two genes terminate with incomplete codons.All tRNAs have the typical clover-leaf structures of mitochondrial tRNAs, with the exception of tRNASer(TGA)-like, with a four stem-and-loop structure.The length of the A+T-rich region of ChBm is 484 bp, shorter than those of JaBm(747 bp) and B.mori(494―499 bp).Phylogenetic analysis among B.mori, ChBm, JaBm, and Antheraea pernyi(Anpe) showed that B.mori is more closely related to ChBm than JaBm.The earliest divergence time estimate for B.mori-ChBm and B.mori-JaBm is about 1.08±0.18―1.41±0.24 and 1.53±0.20―2.01±0.26 Mya, respec-tively.ChBm and JaBm diverged around 1.11±0.16―1.45±0.21 Mya. | PAN MinHui1, YU QuanYou1, XIA YuLing1, DAI FangYin1, LIU YanQun2, LU Cheng1, ZHANG Ze1 & XIANG ZhongHuai1 1 Key Sericultural Laboratory of Agricultural Ministry, Southwest University, Chongqing 400716, China 2 College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110161, China | 2008 | Science China(Life Sciences)2008，51，8： | 16 |
| 17 | Tea-Grown Soils and Tea Quality in Sichuan and Chongqing, China显示文摘Made teas and typical tea-grown soils in Sichuan and Chongqing were collected to investigate soil nutrients, related soil properties and tea quality. The tea-grown soils in Sichuan and Chongqing are distributed mainly in mountainous areas. The high annual precipitation (over 1100 mm), precipitous soil slopes, low cohesion among soil particles and high soil porosity suggested that intensive erosion and leaching might occur in these soils. Moreover, they were very acidic and poor in mineral nutrients such as N, P, K, Ca and Mg except S. The average content of total S was 20.40 g kg-1, much higher than that of organic matter in these soils, revealing that S in the tea-grown soils existed mainly in inorganic forms and very little in organic forms. Water-extractable S accounted for only a small amount of total S, which showed that most parts of sulfur in these soils were insoluble in W8ter. K and S varied greatly in made teas. The concentrations of N and P, however, varied little in these teas even though they differentiated significantly in the tea-grown soils. The high concentration of nitrogen in made teas could result in the high free amino acids and low polyphenol of teas. Significantly positive correlation was established between potassium and polyphenol in made teas. Teas with high ratio of phenol to free amino acids were usually good in taste and appearance. | YUAN LING, WANG SHOUSHENG, WANG ZHIHUI and HUANG JIANGUO (College of Resources and Environment, Southwest Agricultural University, Chongqing 400716 (China)) | 2000 | Pedosphere2000，10，1： | 16 |
| 18 | Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed显示文摘To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found that the current measures have not concerned with how to keep the livelihood of local farmers and herders. The most important measure for ecological protection and restoration is to help the farmers and herders to raise the living standard, which means that they will never need to rely only on the colonizing of croplands, the logging of forests and the grazing of livestock to make a living. | YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China 4. The Ministry of Science and Technology, P. C. China, Beijing 100862, China 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China | 2005 | Science China Earth Sciences2005，48，12： | 15 |
| 19 | High-resolution climate variability of southwest China during 57―70 ka reflected in a stalagmite δ^(18)O record from Xinya Cave显示文摘A 26-cm-long stalagmite (XY2) from Xinya Cave in northeastern Chongqing of China has been ICP-MS 230Th/U dated, showing a depositional hiatus at 2.3 cm depth from the top. The growth of the 2.3―26 cm interval determined by four dates was between 57 ka and 70 ka, with a linear growth rate of 0.023 mm/a. We have analyzed 190 samples for δ 18O and δ 13C, mostly in the 2.3―26 cm part. The δ 18O and δ 13C values between 57 ka and 70 ka reveal decadal-to-centennial climatic variability during the glacial in-terval of Marine Isotope Stage 4 (MIS4), exhibiting much higher resolution than that of the published Hulu and Dongge records during this interval. Speleothem δ 18O in eastern China, including our study area can be used as a proxy of summer monsoon strength, with lighter values pointing to stronger summer monsoon and higher precipitation, and vice versa. Two decreases in the δ 18O signature of XY2 record around 59.5 and 64.5 Ka are argued to correspond to the Dansgaard-Oeschger (D-O) events 17 and 18 respectively. The Heinrich event 6 (H6) can be identified in the record as a heavy δ 18O peak around 60 ka, indicating significant weakening of the monsoon in Chongqing during the cold period. The XY2 δ 18O record shows very rapid change toward to the interstadial condition of the D-O event, but more gradual change toward to the cold stadial condition. This phenomenon found in the Greenland ice core records is rarely observed so clearly in previously published speleothem records. According to SPECMAP δ 18O record, the glacial maximum of MIS 4 was around 64.5 ka with the boundary of MIS 3/4 around 60 ka. Unlike the marine record, the speleothem record of XY2, China, exhibits much high fre-quency variations without an apparent glacial maximum during MIS 4. However, the timing of MIS 3/4 boundary seems to be around 60 ka when the H6 terminated, in agreement with the marine chronology. The growth period of sample XY2 during glacial times probably reflects a local karstic routing of water, rather than having climatic significance. | LI TingYong1, YUAN DaoXian1,2, LI HongChun1,3 ,YANG Yan2, WANG JianLi1, WANG XinYa1, LI JunYun1, QIN JiaMing2, ZHANG MeiLiang2 & LIN YuShi2 1 College of Geographical Science, Southwest University, Chongqing 400715, China 2 Karst Dynamics Laboratory, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China 3 Department of Earth Sciences, Cheng-Kung University, Tainan 70101, Taiwan, China | 2007 | Science China Earth Sciences2007，50，8： | 14 |
| 20 | Centroid-based semi-fragile audio watermarking in hybrid domain显示文摘Many previous (semi-) fragile audio watermarking schemes adopt binary images as watermarks, which reduce the security of watermarking systems. On the other hand, the content-based or feature-based second generation digital watermarking has limited applicability, and its partial feature points may be damaged by watermarking operations and various common signal processing. To overcome these problems, in this paper, a novel centroid-based semi-fragile audio watermarking scheme in hybrid domain is proposed. The theoretical lower limit of signal to noise ratio (SNR) for objective evaluation of the imperceptibility of watermarked audio signal is deduced, and the watermark embedding capacity and the tamper detection ability are theoretically analyzed. In the proposed scheme, first, the centroid of each audio frame is computed, then Hash function is performed on the obtained centroid to get the watermark, after that, the audio sub-band which carries centroid of audio frame is performed with discrete wavelet transform (DWT) and discrete cosine transform (DCT), and finally the encrypted watermark bits are embedded into the hybrid domain. Theoretical analysis and experimental results show that the proposed scheme is inaudible and applicable to different types of audio signals. Furthermore, its ability of tamper detection and tolerance against common signal processing operations are excellent. Comparing with the existing schemes, the proposed scheme can effectively authenticate the veracity and integrity of audio content, and greatly expand the applicability of the content-based audio watermarking scheme. | WANG HongXia & FAN MingQuan School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031, China | 2010 | Science China(Information Sciences)2010，53，3： | 14 |
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