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Seismic multi-arch structures in East China

Science China Earth sciences 2006年第2期49卷 133-146页

作者： YANG Wencai1 & CHEN Zhide2.1.Institute of Geology, chinese academy of geological sciences, beijing 100037, China 2.Daqing Institute of Petroleum Exploration and Production, Daqing 163712. China Institute of Geology Chinese Academy of Geological Sciences Beijing China Daqing Institute of Petroleum Exploration and Production Daqing China

In previous papers (Wencai, 2.02. 2.03), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East China, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is char-acterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic struc-ture and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/Cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East China. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

关键词： deep seismic reflection, multi-arch structure, eclogite bodies, mantle-origin magmatism, East China.

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Dipole anomaly in the Arctic atmosphere and winter Arctic sea ice motion

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Science China Earth sciences 2005年第9期48卷 1529-1536页

作者： WU Bingyi1, ZHANG Renhe1 & WANG Jia2.1. chinese academy of Meteorological {2., beijing 100081, China 2. International Arctic Research center, University of Alaska Fairbanks, AK 99775, USA chinese academy of Meteorological {2. Beijing China International Arctic Research center University of Alaska Fairbanks USA

This paper investigates a previously-ignored atmospheric circulation anomaly-di- pole structure anomaly in the arctic atmosphere, and its relationship with the winter sea ice mo- tion, based on analyses of the International Arctic Buoy Programme Data (1979―1998) and datasets from the national {2. for Environmental Prediction (NCEP) and the national {2. for Atmospheric Research (NCAR) for the period of 1960―2.02. The dipole structure anomaly is the second-leading mode of EOF of monthly mean SLP north of 70°N during the winter season (Oct.―Mar.), which accounts for 13% of the variance. One of its two anomaly {2.s is over the Canadian Archipelago; the other is situated over northern Eurasia and the Siberian marginal seas. Due to the dipole structure anomaly’s strong meridionality, it becomes an important mechanism to drive both anomalous sea ice export out of the Arctic Basin and cold air outbreaks into the Barents Sea, the Nordic Seas and northern Europe.

关键词： dipole anomaly, winter season, Arctic, sea ice motion, sea ice export.

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chinese national clinical practice guidelines on prevention, diagnosis and treatment of early colorectal cancer

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中华医学杂志(英文版) 2024年第17期137卷 2024 Aug 6页

作者： Li Jingnan Yao Hongwei Lu Yun Zhang Shutian Zhang Zhongtao Society of Digestive Endoscopy of the chinese Medical Association Colorectal Surgery Group of the chinese Medical Association chinese Association of Gastroenterologist & Hepatologist national Clinical Research center for Digestive Diseases chinese Medical Journal Clinical Practie Guideline Collaborative Department of Gastroenterology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing China Department of General Surgery Beijing Friendship Hospital Capital Medical University National Clinical Research Center for Digestive Diseases Beijing China Department of General Surgery The Affiliated Hospital of Qingdao University Qingdao Shandong China Department of Gastroenterology Beijing Friendship Hospital Capital Medical University National Clinical Research Center for Digestive Disease Beijing China

Background: The incidence and mortality of colorectal cancer (CRC) in China are increasing in recent years. The clarified pathogenesis and detectable precancerous lesions of CRC make it possible to prevent, screen, and diagnose CRC at an early stage. With the development of endoscopic and surgical techniques, the choice of treatment for early CRC is also worth further discussion, and accordingly, a standard follow-up program after treatment needs to be ***: This clinical practice guideline (CPG) was developed following the recommended process of the World Health Organization, adopting Grading of Recommendations Assessment, Development and Evaluation (GRADE) in assessing evidence quality, and using the Evidence to Decision framework to formulate clinical recommendations, thereby minimizing bias and increasing transparency of the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guides to ensure the guideline’s completeness and ***: This CPG comprises 46 recommendations concerning prevention, screening, diagnosis, treatment, and surveillance of CRC. In these recommendations, we have indicated protective and risk factors for CRC and made recommendations for chemoprevention. We proposed a suitable screening program for CRC based on the chinese context. We also provided normative statements for the diagnosis, treatment, and surveillance of CRC based on existing clinical evidence and ***: The 46 recommendations in this CPG are formed with consideration for stakeholders’ values and preferences, feasibility, and acceptability. Recommendations are generalizable to resource-limited settings with similar CRC epidemiology pattern as China.

关键词： Colorectal cancer Early detection of cancer Prevention Screening Diagnosis Treatment Follow-up Guideline

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Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3 & HAN Bin1,3,41. national center for Gene Research, Shanghai Institutes for Biological {2., chinese academy of {2., Shanghai 2.02.3, China 2. Graduate School of the chinese academy of {2., beijing 100039, China 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological {2., chinese academy of {2., Shanghai 2.0032. China national center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate School of the chinese academy of {2. Beijing China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3′-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953 genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3′ fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3′ fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

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Some evidence of drying trend over northern China from 1951 to 2.04

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chinese Science Bulletin 2006年第23期51卷 2913-2925页

作者： MA Zhuguo1,2.& FU Congbin1,2.1. Key Laboratory of Regional Climate-Environment for Temperate East Asia, chinese academy of {2., beijing 10002., China 2. START Regional center for Temperate East Asia, Institute of Atmos-pheric Physics, chinese academy of {2., beijing 10002., China Key Laboratory of Regional Climate-Environment for Temperate East Asia Chinese Academy of Sciences Beijing China START Regional center for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over China were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern China in the last 54 years was revealed, and the evidence of drying trend over northern China was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest China and the central part of North China since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2. During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest China and the central part of North China in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast China, one was in the mid 1990s and the other two were in 1965 and 1983, respectively; (3) Unlike the variation trend of other subregions of northern China, the western part of Northwest China is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest China, the central part of North China and Northeast China since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions.

关键词：中国北方干燥趋向干旱索引气候背景

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Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science China Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2. DING Yihui3 & ZHANG Renhe2.1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 2.0044, China 2. State Key Laboratory of Severe Weather (LaSW), chinese academy of Meteorological {2., beijing 100081, China 3. national Climate center, chinese Meteorological Administration, beijing 100081, China Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing China State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing China national Climate center Chinese Meteorological Administration Beijing China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-China Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-China Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-China Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-China Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-China Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-China Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-China Peninsula to South China Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-China Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

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Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science China Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth sciences and Natural Resources, China University of Geosciences, {2. 100083, China 2. Faculty of Earth sciences, China University of Geosciences, Wuhan 430074, China 3. {2. SHRIMP center, Institute of Geology, chinese academy of geological sciences, beijing 100037, China Faculty of Earth sciences and Natural Resources China University of Geosciences Beijing China Faculty of Earth sciences China University of Geosciences Wuhan China beijing SHRIMP center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South China: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2. Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits Research and center for Marine Geochemistry Research, Department of Earth sciences, Nanjing University, Nanjing 2.0093, China 2. Tarim Oilfield Company Exploration & Development Research Institute, Ku’erle 841000, China 3. Institute of Mineral Resources,{2., beijing 100037, China) State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Exploration and Development Research Institute Tarim Oilfield Company Ku'erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South China. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-2.). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (2..4—2..3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science China Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, Research center for Eco-Environmental sciences, {2. academy of sciences, beijing 100085, China 2. School of Civil Engineering & Architecture, beijing Jiaotong University, beijing 100044, China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China School of Civil Engineering & Architecture Beijing Jiaotong University Beijing China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

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chinese national clinical practice guidelines on the prevention,diagnosis,and treatment of early gastric cancer

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chinese Medical Journal 2024年第8期137卷 887-908页

作者： Peng Li Ziyu Li Enqiang Linghu Jiafu Ji Society of Digestive Endoscopy of the chinese Medical Association Colorectal Surgery Group of the chinese Medical Association chinese Association of Gastroenterologists&Hepatologists national Clinical Research center for Digestive Diseases chinese Medical Journal Clinical Practice Guideline Collaborative Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseaseBeijing 100050China Department of Gastrointestinal Surgery Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Peking University Cancer Hospital and InstituteBeijing 100142China Department of Gastroenterology and Hepatology the First Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China 不详

Background:Gastric cancer is one of the most common malignant tumors in the digestive system in *** comprehensive practice guidelines for early gastric cancer in China are currently ***,we created the chinese national clinical practice guideline for the prevention,diagnosis,and treatment of early gastric ***:This clinical practice guideline(CPG)was developed in accordance with the World Health Organization’s recommended process and with the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)in assessing evidence *** used the Evidence to Decision framework to formulate clinical recommendations to minimize bias and increase transparency in the CPG development *** used the Reporting Items for practice Guidelines in HealThcare(RIGHT)statement and the Appraisal of Guidelines for Research and Evaluation II(AGREE II)as reporting and conduct guidelines to ensure completeness and transparency of the ***:This CPG contains 40 recommendations regarding the prevention,screening,diagnosis,treatment,and follow-up of early gastric cancer based on available clinical studies and *** provide recommendations for the timing of Helicobacter pylori eradication,screening populations for early gastric cancer,indications for endoscopic resection and surgical gastrectomy,follow-up interval after treatment,and other ***:This CPG can lead to optimum care for patients and populations by providing up-to-date medical *** intend this CPG for widespread adoption to increase the standard of prevention,screening,diagnosis,treatment,and follow-up of early gastric cancer;thereby,contributing to improving national health care and patient quality of life.

关键词： Early gastric cancer Prevention Screening Diagnosis Treatment Follow-up

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