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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, China

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Science China Earth Sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,bao ZengKuan2,DONG JinQuan2,GUO ZhaoJie3 & DENG Jun1 1 State Key Laboratory of Geological Processes and Mineral Resources,China university of geosciences,beijing100083,China 2 Laboratory of Nuclear Analysis Techniques,Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100039,China 3 department of Geology,Peking university,beijing 100871,China 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 289 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～250℃ for zircon fission track,and metallogenetic temperature of 120―350℃ in this ore *** three mineralization epochs have been identified,i.e.,289―276 Ma,232―200 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132 Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～250℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 20 Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

INFLUENCES OF MARINE FLOOR HYDROTHERMAL ACTIVITY ON ORGANIC MATTER ABUNDANCE IN MARINE CARBONATE ROCKS——A CASE STUDY OF MIDDLE-UPPER PROTEROZOIC IN THE NORTHERN PART OF NORTH CHINA

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Chinese Science Bulletin 2006年第5期51卷 585-593页

作者： WANG Jie CHEN Jianfa bao zhidong ZHANG Shuichang XU Yongchang WANG Darui Wuxi Institute of Oil Geology Sinopec Wuxi 214151 China Geoscience department of Zhejiang university Hangzhou 310028 China Geochemistry department of Yangtze university Jingzhou 434023 China Chinese university of petroleum Beijing 102249 China Research Institute of petroleum Exploration and Development Petro China Beijing 100083 China Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou 730000 China

Study indicates that the elements rich in marine floor hydrothermal fluids have a positive in- fluence, not only on total organic carbon (TOC), but also on the abundance of SiO2 in some Middle-Upper Proterozoic strata. The TOC bears a better positive correlation with abundance of SiO2. By the correlation analysis between organic matter and sea-floor hot fluid characterized trace elements such as P, Cu, Zn, Ni, Ba, etc in marine carbonate rocks, we conclude that organic matter enrichment of carbonate rocks were related to marine floor hydrothermal activity in a part of layers. Some thin-layered cherts, which were thought to be the indicators of hydrothermal activity, frequently occurring in Gaoyuzhuang, Wumishan, Tieling and Xiamaling formation support our conclu- sion. With the increasing of trace elements in marine carbonate rocks, the TOC and Fe/Ti ratio is creasing. In contrast, the Al/(Al+Fe+Mn) ratio is usually de- creasing.

关键词：华北北部元古代碳酸盐岩有机物质海底热流体主要元素微量元素

Monitoring early responses to irradiation with dual-tracer micro-PET in dual-tumor bearing mice

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World Journal of Gastroenterology 2010年第43期16卷 5416-5423页

作者： Hui Wang, Jia-He Tian, Bai-Xuan Xu, Zhi-Wei Guan, ChangBin Liu, Rui-Min Wang, Ying-Mao Chen, Jin-Ming Zhang, Nuclear Medicine department, The General Hospital of the Chinese People’s Liberation Army and Military Medical Postgraduate College, beijing 100853, China Bo Liu, department of Hepatobiliary Surgery, The General Hospital of the Chinese People’s Liberation Army and Military Medical Postgraduate College, beijing 100853, China bao-Lin Qu, department of Radiation Oncology, The General Hospital of the Chinese People’s Liberation Army and Military Medical Postgraduate College, beijing 100853, China Nuclear Medicine department The General Hospital of the Chinese People's Liberation Army and Military Medical Postgraduate College 28 Fuxing Road Haidian District Beijing 100853 China. tianjh@***

AIM: To monitor the early responses to irradiation in primary and metastatic colorectal cancer (CRC) with 18 Ffluorothymidine ( 18 F-FLT) and 18 F-fluorodeoxyglucose ( 18 F-FDG) small-animal position emission tomography (micro-PET). METHODS: The primary and metastatic CRC cell lines, SW480 and SW620, were irradiated with 5, 10 and 20, l l l , Gy. After 24 h, the cell cycle phases were analyzed. A dual-tumor-bearing mouse model of primary and metastatic cancer was established by injecting SW480 and SW620 cells into mice. micro-PET with 18 F-FLT and 18 F-FDG was performed before and 24 h after irradiation with 5, 10 and 20 Gy. The region of interest (ROI) was drawn over the tumor and background to calculate the ratio of tumor to non-tumor (T/NT) in tissues. Immunohistochemical assay and Western blotting were used to examine the levels of integrin β3, Ki-67, vascular endothelial growth factor receptor 2 (VEGFR2) and heat shock protein 27 (HSP27). RESULTS: The proportion of SW480 and SW620 cells in the G 2 -M phase was decreased with an increasing radiation dose. The proportion of SW480 cells in the G 0 -G 1 phase was increased from 48.33% ± 4.55% to 87.09% ± 7.43% (P < 0.001) and that of SW620 cells in the S-phase was elevated from 43.57% ± 2.65% to 66.59% ± 7.37% (P = 0.021). In micro-PET study, with increasing dose of radiation, 18 F-FLT uptake was significantly reduced from 3.65 ± 0.51 to 2.87 ± 0.47 (P = 0.008) in SW480 tumors and from 2.22 ± 0.42 to 1.76 ± 0.45 (P = 0.026) in SW620 tumors. 18 F-FDG uptake in SW480 and SW620 tumors was reduced but not significantly (F = 0.582, P = 0.633 vs F = 0.273, P = 0.845). Dose of radiation was negatively correlated with 18 F-FLT uptake in both SW480 and SW620 tumors (r = -0.727, P = 0.004; and r = -0.664, P = 0.009). No significant correlation was found between 18 F-FDG uptake and radiation dose in SW480 or SW620 tumors. HSP27 and integrin β3 expression was higher in SW480 than in SW620 tumors. The T/NT ratio for 18 F-FLT up

关键词： 18 F-fluorothymidine 18 F-fluorodeoxyglucose Irradiation Positron emission tomography Colorectal cancer

Effects of algae contamination on the hydrophobicity of high-voltage composite insulators

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High Voltage 2019年第3期4卷 234-240页

作者： Shifang Yang zhidong Jia Xiaogang Ouyang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environment Graduate School at ShenzhenTsinghua UniversityTaoyuan Street Nanshan DistrictShenzhen 518055People's Republic of China department of Electrical Engineering Tsinghua UniversityHaidian DistrictBeijing 100084People's Republic of China

Algae colonisation has been observed on silicone rubber insulators around the world especially in a subtropical climate because the moderate temperature and moisture could aggravate the growth of algae upon silicone rubber *** surface of these insulators easily forms a water film,and the originally excellent hydrophobicity is decreased or even *** study explores the regularity of the hydrophobicity changes and the underlying *** on the solid layer method,silicone rubber samples were found with algae and inorganics quantitatively,and their contact angles were measured after reservation under different humidity *** results showed that although inorganic ash could accelerate the hydrophobic recovery process,algae colonisation decisively decreased the hydrophobicity,especially in moist *** an extensive investigation of biological contaminants,it was found that the appearance of algae was independent of inorganics,but algae could accelerate the accumulation of inorganics through water absorptivity and the viscosity of *** water absorption ability of algae was compared with that of inorganic ash and sugar,and their difference was deduced to be due to the environmental adaptability of the algae organisms,which was reflected mainly in a dry *** microscopy analysis of bio-contaminants was conducted through SEM.

关键词： algae inorganic rubber

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左半结肠癌中央组淋巴结分布特点及外科清扫

中华胃肠外科杂志 2024年第9期27卷 914-918页

作者：鲍予頔高志冬北京大学人民医院胃肠外科外科肿瘤实验室北京100044

淋巴结转移是结直肠癌的主要转移途径之一,也是决定患者预后的重要因素。引流区域的淋巴结清扫,尤其是肿瘤相关供血动脉根部的中央组淋巴结清扫是外科手术技术的要点和难点。目前,关于左半结肠癌淋巴回流及中央组淋巴结(第253组淋巴结)... 详细信息

淋巴结转移是结直肠癌的主要转移途径之一,也是决定患者预后的重要因素。引流区域的淋巴结清扫,尤其是肿瘤相关供血动脉根部的中央组淋巴结清扫是外科手术技术的要点和难点。目前,关于左半结肠癌淋巴回流及中央组淋巴结(第253组淋巴结)的分布规律尚不清楚,中央组淋巴结清扫的必要性及范围也未达成统一共识,导致实际临床工作中不同医师对淋巴结清扫程度差异较大,且缺乏外科手术质控标准,影响术后治疗方案的选择及患者远期预后。同时,对于淋巴结回流及转移的研究,目前多以传统解剖学为基础,仅基于尸体解剖的现象描述、归纳和推测,不能满足外科手术清扫淋巴结时的个体化和精准化要求;而以功能解剖学为前提的术前及术中的淋巴结显像技术在结直肠癌患者中的应用也在进一步探索中。

关键词：结肠肿瘤,左半中央组淋巴结 D3清扫功能解剖学

Target-oriented Q-compensated reverse-time migration by using optimized pure-mode wave equation in anisotropic media

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petroleum Science 2023年第2期20卷 866-878页

作者： Shi-Gang Xu Qian-Zong bao Zhi-Ming Ren Chang'an university School of Geological Engineering and GeomaticsDepartment of GeophysicsXi'anShaanxi710064China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing100028China

Research on seismic anisotropy and attenuation plays a significant role in exploration geophysics. To enhance the imaging quality for complicated structures, we develop several effective improvements for anisotropic attenuation effects in reverse-time migration (Q-RTM) on surface and vertical seismic profiling (VSP) acquisition geometries. First, to suppress pseudo-shear wave artifact and numerical instability of the commonly used anisotropic pseudo-acoustic wave equations, an optimized pure P-wave dispersion relation is derived and the corresponding pure-mode wave equation is solved by combining the finite-difference and Possion methods. Second, a simplified anisotropic pure-mode visco-acoustic wave equation (PVAWE) based on standard linear solid model is established. Third, a time-dispersion correlation strategy is applied to improve the modeling accuracy. Fourth, we extend a target-oriented scheme to anisotropic attenuated modeling and imaging. Instead of the conventional wavefield modeling and RTM, the proposed approach can extract available wavefield information near the target regions and produce high imaging resolution for target structures. Last, both anisotropic surface and VSP Q-RTMs are executed by combining optimized PVAWE, time-dispersion correlation and target-oriented algorithm. Modeling examples demonstrate the advantages of our schemes. Moreover, our modified Q-compensated imaging workflow can be regarded as a supplement to the classical anisotropic RTM.

关键词： Anisotropy Attenuation Reverse-time migration Wave equation Optimized algorithm Target-oriented

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World Journal of Pediatrics 2021年第4期17卷 335-340页

作者： Qing-You Zhang Bo-Wen Xu Jun-bao Du department of Pediatrics Peking University First HospitalXi-An Men Street No.1West DistrictBeijing100034China

Background Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has been spreading rapidly around the world,while“multisystem inflammatory syndrome in children”(MIS-C)is a new type of syndrome that has now been reported in many *** and different characteristics between KD and MIS-C have been reported in a variety of *** aimed to focus on reviewing clinical presentations,diagnosis,and treatment of KD and *** We searched articles in the electronic databases,including the Cochrane Library database,EMBASE,and MEDLINE with the keywords“multiple inflammatory syndrome”and/or“COVID-19”and/or“Kawasaki disease”and“children”.Results Main presentations of MIS-C and KD include fever,rashes,mucous membrane involvement,conjunctivitis,hands and feet erythema/edema,and cervical ***,compared with the highest incidence of KD among some Asian countries,MIS-C is common among Black and Hispanic ***-C is common in older children and teenagers,whereas classic KD is common in children under five years of *** symptoms,shock,and coagulopathy are common in MIS-C patients but are not common in classic *** manifestations are more common than KD,including myocarditis with cardiac dysfunction and coronary artery dilation or *** cases in MIS-C present with vasodilated or cardiogenic shock that requires fluid resuscitation,muscular support,and even mechanical ventilation and extracorporeal membrane oxygenation(ECMO),whereas KD rarely presents with these manifestations and requires these *** serum ferritin,leukopenia,lymphopenia and thrombocytopenia are common in ***,thrombocytosis is a characteristic feature of *** immunoglobulin(IVIG)and moderate-high dose aspirin are still a standard recommended treatment for *** addition to the above-mentioned medications,steroids and biological drugs are frequently used in patients with *** of the chil

关键词： Kawasaki disease Multisystem inflammatory syndrome Children

Differential diagnosis of vasovagal syncope and postural tachycardia syndrome in children

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World Journal of Pediatrics 2020年第6期16卷 549-552页

作者： Yuan-Yuan Wang Jun-bao Du Hong-Fang Jin department of Pediatrics Peking University First HospitalNo.1Xi'an-men Street.West DistrictBeijing 100034China Key Lab of Molecular Cardiovascular Sciences The Ministry of EducationBeijing 100191China

Orthostatic intolerance(OI)is defined as a syndrome consisting of a group of clinical symptoms including headache,dizziness,palpitation,chest tightness,nausea,vomiting,pale complexion,and even syncope due to the inability to tolerate the upright *** condition is relieved by recumbence[1,2].OI is common and affects the quality of life and the psychosocial well-being[3-5]Previous studies have shown that the pathogenesis of OI is mainly related to the enhanced endothelium-dependent diastolic function[6],abnormal Bezold-Jarisch reflex[7],central hypovolemia[8],and autonomic dysfunction[9].

关键词： diagnosis syncope tachycardia

Insights into postural orthostatic tachycardia syndrome after COVID-19 in pediatric patients

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World Journal of Pediatrics 2024年第3期20卷 201-207页

作者： Ya-Xi Cui Jun-bao Du Hong-Fang Jin department of Pediatrics Peking University First HospitalNo.1 Xi-an Men StreetWest DistrictBeijing 100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China

The pandemic caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)profoundly threatened human health globally and greatly impacted the world economy[1].While most patients recovered,some suff... 详细信息

关键词： acute patients tachycardia