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Effect of acetylcholine on pain-related electric activities in hippocampal CA1 area of normal and morphinistic rats
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作者 肖宇 杨晓芳 徐满英 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第6期323-328,共6页
Objective To examine the effect of acetylcholine(ACh)on the electric activities of pain-excitation neurons (PEN)and pain-inhibitation neurons(PIN)in the hippocampal CA1 area of normal rats or morphinistic rats,a... Objective To examine the effect of acetylcholine(ACh)on the electric activities of pain-excitation neurons (PEN)and pain-inhibitation neurons(PIN)in the hippocampal CA1 area of normal rats or morphinistic rats,and to explore the role of ACh in regulation of pain perception in CA1 area under normal condition and morphine addiction.Methods The trains of electric impulses applied to sciatic nerve were set as noxious stimulation.The discharges of PEN and PIN in the CA l area were recorded extracellularly by glass microelectrode.We observed the influence of intracerebroventricular (i.c.v.)injection of ACh and atropine on the noxious stimulation-evoked activities of PEN and PIN in the CA1 area.Results Noxious stimulation enhanced the electric activity of PEN and depressed that of PIN in the CA1 area of both normal and addiction rats.In normal rats,ACh decrease the pain-evoked discharge frequency of PEN,while increased the frequency of PIN.These effects reached the peak value at 4 min after injection of ACh.In morphinistic rats,ACh also inhibited the PEN electric activity and potentialized the PIN electric activity,but the maximum effect appeared at 6 min after administration. The ACh-induced responses were significantly blocked by muscarinic receptor antagonist atropine.Conclusion Cholinergic neurons and muscarinic receptors in the hippocampal CA1 area are involved in the processing of nociceptive information and they may play an analgesia role in pain modulation.Morphine addiction attenuated the sensitivity of painrelated neurons to the noxious information. 展开更多
关键词 ACETYLCHOLINE hippocampal CA1 area MORPHINE electric activity
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Comparative analysis of GF-1,HJ-1,and Landsat-8 data for estimating the leaf area index of winter wheat 被引量:16
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作者 LI He CHEN Zhong-xin +4 位作者 JIANG Zhi-wei WU Wen-bin REN Jian-qiang LIU Bin Tuya Hasi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期266-285,共20页
Using simultaneously collected remote sensing data and field measurements, this study firstly assessed the consistency and applicability of China high-resolution earth observation system satellite 1 (GF-1) wide fiel... Using simultaneously collected remote sensing data and field measurements, this study firstly assessed the consistency and applicability of China high-resolution earth observation system satellite 1 (GF-1) wide field of view (WFV) camera, environment and disaster monitoring and forecasting satellite (H J-l) charge coupled device (CCD), and Landsat-8 opera- tional land imager (OLI) data for estimating the leaf area index (LAI) of winter wheat via reflectance and vegetation indices (VIs). The accuracies of these LAI estimates were then assessed through comparison with an empirical model and the PROSAIL radiative transfer model. The effects of radiation calibration, spectral response functions, and spatial resolution on discrepancies in the LAI estimates between the different sensors were also analyzed. The results yielded the following observations: (1) The correlation between reflectance from different sensors is relative good, with the adjusted coefficients of determination (R2) between 0.375 to 0.818. The differences in reflectance are ranging from 0.002 to 0.054. The correlation between VIs from different sensors is high with the R2 between 0.729 and 0.933. The differences in the VIs are ranging from 0.07 to 0.156. These results show the three sensors' images can all be used for cross calibration of the reflectance and VIs. (2) The four VIs from the three sensors are all demonstrated to be highly correlated with LAI (R2 between 0.703 and 0.849). The linear models associated with the 2-band enhanced vegetation index (EVI2), which feature the highest R2 (higher than 0.746) and the lowest root mean square errors (RMSE) (less than 0.21), were selected to estimate the winter wheat LAI. The accuracy of the estimated LAI from Landsat-8 was the highest, with the relative errors (RE) of 2.18% and an RMSE of 0.13, while the H J-1 was the lowest, with the RE of 2.43% and the RMSE of 0.15. (3) The inversion errors in the different sensors' LAI estimates using the PROSAIL model are small. The accuracy of the GF-1 is the highest with the RE of 3.44%, and the RMSE of 0.22, whereas that of the H J-1 is the lowest with the RE of 4.95%, and the RMSE of 0.26. (4) The effects of the spectral response function and radiation calibration for the different sensors are small and can be ignored, but the effects of spatial resolution are significant and must be taken into consideration in practical applications. 展开更多
关键词 GF-1 WFV H J-1 CCD Landsat-80LI leaf area index PROSAIL vegetation indices
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An Investigation of Crocidolite Contamination and Mesothelioma in a Rural Area of China^1 被引量:3
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作者 LIU XUEZE, LUO SUQIONG, WANG ZHIMING, WANG MIANZHEN, AND ZHAN CHENGLIE Department of Occupational Health, School of Public Health, West China University of Medical Sciences, Chengdu. Sichuan. China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第2期156-165,共10页
Crocidolite was found to be ubiquitous in a county in southwestern China. It had been widely used in the making of road pavement, stoves, wall paint, etc. The environmental levels of the asbestos fibers were determine... Crocidolite was found to be ubiquitous in a county in southwestern China. It had been widely used in the making of road pavement, stoves, wall paint, etc. The environmental levels of the asbestos fibers were determined. Of the 2175 local residents examined. 16 had asbestosis and 232 had pleural plaques. These clinical manifestations were noted mainly in patients over 50 years of age. (c)1990 Academic Press. Inc. 展开更多
关键词 An Investigation of Crocidolite Contamination and Mesothelioma in a Rural area of China~1
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Fluoxetine ameliorates cognitive impairments induced by chronic cerebral hypoperfusion via down-regulation of HCN2 surface expression in the hippocampal CA1 area
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期78-78,共1页
Aim To investigate whether tluoxetine, a selective serotonin reuptake inhibitor( SSRI) , could amelio- rate cognitive impairments induced by chronic cerebral hypopeffusion in rats and to clarify the underlying mecha... Aim To investigate whether tluoxetine, a selective serotonin reuptake inhibitor( SSRI) , could amelio- rate cognitive impairments induced by chronic cerebral hypopeffusion in rats and to clarify the underlying mecha- nisms of its efficacy. Methods Rats were subjected to permanent bilateral occlusion of the common carotid arteries (two-vessel occlusion, 2VO). Two weeks later, rats were treated with 30 mg · kg^-1 fluoxetine (intragastric injec- tion, i. g. ) for 6 weeks. Cognitive function was evaluated by Morris water maze (MWM) and novel objects recog- nition (NOR) test. Long-term potentiation (LTP) was used to address the underlying synaptic mechanisms. West- ern blot was used to quantify the protein levels. Results Fluoxetine treatment significantly improved the cognitive 2VO impairments caused by 2VO, accompanied with a reversion of 2VO-induced inhibitory of LTP. Furthermore, caused an up-regulation of hyperpolarization-activated cyclic nueleotide-gated channel 2 (HCN2) surface expres- sions in the hippocampal CA1 area and fluoxetine also effectively recovered the up-regulation of HCN2 surface ex- pressions. Conclusion Fluoxetine can ameliorate cognitive impairments induced by chronic cerebral hypopeffusion and a possible mechanism may via down-regulating HCN2 surface expression in the Hippocampal CA1 area. 展开更多
关键词 FLUOXETINE chronic cerebral HYPOPERFUSION cognitive IMPAIRMENTS HCN2 subunit HIPPOCAMPAL CA1area rats
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Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2018-2022
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作者 Yu-Long KANG Shi-Chang KANG +5 位作者 Wan-Qin GUO Tao CHE Zong-Li JIANG Zhen-Feng WANG Qiang-Qiang XU Cheng-De YANG 《Advances in Climate Change Research》 SCIE CSCD 2024年第2期297-311,共15页
Ice sheet serves as a crucial indicator for assessing climate change.Mass loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface v... Ice sheet serves as a crucial indicator for assessing climate change.Mass loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface velocity.However,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal monitoring.This study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2 satellites during 2018-2022.The results indicate that the glacier area reduced by approximately 166.1±44.2 km^(2)(-0.2%±0.1%per year)during the study period,with an acceleration after 2020(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern NAP.The maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2021 were the highest(exceeded 4210 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing trend.The glacier G012158E47018N,McNeile Glacier,glacier G299637E64094S and Drygalski Glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their termini.Our results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere processes.Therefore,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios. 展开更多
关键词 Glacier area Seasonal ice speed Sentinel 1&2 northern Antarctic Peninsula Ice-ocean-atmosphere processes
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Building a Comprehensive Well-off Society in Yunnan's Minority Areas A Study of the Prediction on the Differences in Economic Development Indexes
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作者 Yunhong GONG Fang RAO 《International Journal of Technology Management》 2015年第9期116-122,共7页
Based on the gray theory and GM (1, 1) model, the various indexes in 2013-2020 are predicted using the data of all indexes of the economic development of Yunnan' s 8 minority areas in 2013-2020 and also compared wi... Based on the gray theory and GM (1, 1) model, the various indexes in 2013-2020 are predicted using the data of all indexes of the economic development of Yunnan' s 8 minority areas in 2013-2020 and also compared with the standard values of all indexes of building a well-off society in 2020, and the differences between them are analyzed. The purpose of this study is to provide a reference basis for Yunnan province' s government to analyze the economic development of the minority areas. 展开更多
关键词 Yurman' s Minority areas Gray System theory GM 1 1 Prediction Model
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Analysis on Characteristics of Seismic Damage of the Nepal M_S8.1 Earthquake in the Tibet Area of China
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作者 Gao Jinrui Nyima +1 位作者 Wen Shengliang Zhang Jianlong 《Earthquake Research in China》 CSCD 2016年第2期271-280,共10页
On April 25,2015,a M_S8. 1 earthquake occurred in Nepal. In the Tibet area of China,this earthquake caused heavy casualties and damage to housing,roads,communications,other lifeline engineering, water conservancy and ... On April 25,2015,a M_S8. 1 earthquake occurred in Nepal. In the Tibet area of China,this earthquake caused heavy casualties and damage to housing,roads,communications,other lifeline engineering, water conservancy and other infrastructure. This paper introduces the basic situation of the earthquake,and based on the investigation and assessment of seismic intensity,the damage of the disaster area is analyzed,and building types and damage to the lifeline systems and various industries are given. Through the analysis of the characteristics of the earthquake disaster,this paper points out the existing problems in seismic fortification,and finally puts forward proposals for the prevention and control of earthquake geological disasters, scientific planning for the restoration and reconstruction,strengthening earthquake prevention and disaster reduction propaganda,improving the awareness of earthquake preparedness in the agricultural and pastoral areas,strengthening the guidance and supervision of housing construction in rural areas to reduce the casualties and losses,and promoting the harmonious development of economy in Tibet. 展开更多
关键词 Nepal Ms8. 1 earthquake Tibet area Earthquake survey Seismic damagecharacteristics
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The Test Area of Suizhong 36-1 Oil Field Fully Under Commission
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作者 Yan Hao 《China Oil & Gas》 CAS 1995年第3期14-14,共1页
TheTestAreaofSuizhong36-1OilFieldFullyUnderCommission¥//Suizhong36-lOilfieldlocatedin.LiaodongGulf,coveringa... TheTestAreaofSuizhong36-1OilFieldFullyUnderCommission¥//Suizhong36-lOilfieldlocatedin.LiaodongGulf,coveringanareaof48km2Theoi... 展开更多
关键词 TEST the Test area of Suizhong 36-1 Oil Field Fully Under Commission
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新集矿区深部1煤层底板奥灰岩溶突水危险性评价 被引量:1
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作者 韩锋 詹润 +3 位作者 孙贵 顾承串 李宏泽 雷震 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2024年第8期1080-1086,共7页
奥灰岩溶裂隙含水层是影响华北型煤矿深部开采的重要水害,在水-岩相互作用下奥灰含水层易导致煤层底板突水。为进一步认识奥灰岩溶突水问题,文章以新集矿区深部1煤层开采为例,利用矿区近些年最新积累的奥灰钻孔资料,选取断层强度指数、... 奥灰岩溶裂隙含水层是影响华北型煤矿深部开采的重要水害,在水-岩相互作用下奥灰含水层易导致煤层底板突水。为进一步认识奥灰岩溶突水问题,文章以新集矿区深部1煤层开采为例,利用矿区近些年最新积累的奥灰钻孔资料,选取断层强度指数、断层交叉点与尖灭点、含水层水压、富水性、隔水层等效厚度、脆塑比7个因素作为奥灰岩溶突水的主控因素,并结合层次分析法(analytic hierarchy process,AHP)确定各主控因素影响权重。运用地理信息系统(geographic information system,GIS)空间分析功能建立各主控因素专题图,通过对专题栅格图归一化处理,将各主控因素按照权重进行空间复合叠加,最终获得1煤层底板奥灰岩溶突水危险性评价分区结果。将评价结果与突水系数法计算结果对比分析可知,基于GIS的煤层底板突水危险性评价方法更符合矿区实际地质情况,可以为矿区深部煤层开采与水害防治工作提供参考依据。 展开更多
关键词 层次分析法(AHP) 地理信息系统(GIS) 新集矿区 1煤层 底板 奥陶系灰岩 突水
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塔西南山前地区柯克亚周缘叶探1井油气勘探重大突破及意义
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作者 王清华 杨海军 +5 位作者 李勇 蔡振忠 杨宪彰 谢会文 陈才 孙春燕 《中国石油勘探》 CAS CSCD 北大核心 2024年第4期1-16,共16页
塔西南山前西昆仑冲断带柯东构造带叶探1井在二叠系普斯格组获得重大突破,标志着塔西南山前地区发现一个重要的勘探接替层系。结合区域地质资料,根据野外露头、钻井、地震等综合研究,对柯克亚周缘二叠系普斯格组的成藏条件进行再认识。... 塔西南山前西昆仑冲断带柯东构造带叶探1井在二叠系普斯格组获得重大突破,标志着塔西南山前地区发现一个重要的勘探接替层系。结合区域地质资料,根据野外露头、钻井、地震等综合研究,对柯克亚周缘二叠系普斯格组的成藏条件进行再认识。研究认为,研究区内二叠系普斯格组发育陆相湖泊—三角洲沉积体系,上段发育半深湖—深湖相烃源岩,面积1.0×10^(4)km^(2),厚度最大达到800m,集中段有机质丰度为0.92%~1.16%,以菌藻类生源为主,有机质类型主要为Ⅱ型,有机质丰度高;普斯格组下段发育三角洲前缘、滨浅湖沙坝优质砂岩储层,砂体厚度为42.5~63m,砂地比为27%~47%,是一套分布较广的区域性储层,与普斯格组上段泥岩组成优质储盖组合;柯克亚周缘发育印支期、喜马拉雅期两期构造变形,古生界叠瓦冲断、强烈逆掩叠置,圈闭成排成带,喜马拉雅期进一步挤压抬升改造,局部复杂化,形成的叠瓦冲断带为勘探有利区。根据普斯格组天然气干燥系数分析,折算Ro为1.31%~1.42%,与下盘烃源岩成熟度相当,表明油气来自下盘逆掩叠置烃源岩,经历早油晚气的成藏过程,成藏具有“逆掩叠置下盘供烃、下生上储、断裂输导”的特点。综合分析认为该地区二叠系普斯格组圈闭成排成带分布,已发现圈闭9个,面积301km^(2),天然气资源量约为2930×10^(8)m^(3),凝析油资源量约为2×10^(8)t,具有较好的勘探前景。 展开更多
关键词 塔西南山前地区 柯克亚周缘 二叠系普斯格组 叶探1 重大发现 成藏条件
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基于HJ-1星和GF-1号影像融合特征提取冬小麦种植面积 被引量:1
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作者 张宏 李卫国 +4 位作者 张晓东 卢必慧 张琤琤 李伟 马廷淮 《中国农业科技导报》 CAS CSCD 北大核心 2024年第2期109-119,共11页
为提高基于国产环境与灾害监测预报卫星(HJ-1/CCD)影像大范围提取冬小麦种植面积的精度,以江苏省宿迁市沭阳县为研究区域,对冬小麦拔节期30 m×30 m的HJ-1/CCD多光谱影像和2 m×2 m的高分1号卫星全色影像(GF-1/PMS)进行融合与... 为提高基于国产环境与灾害监测预报卫星(HJ-1/CCD)影像大范围提取冬小麦种植面积的精度,以江苏省宿迁市沭阳县为研究区域,对冬小麦拔节期30 m×30 m的HJ-1/CCD多光谱影像和2 m×2 m的高分1号卫星全色影像(GF-1/PMS)进行融合与面向对象分类研究。将GF-1/PMS全色影像进行8、16和24 m重采样,得到4种空间分辨率(含2 m)的全色影像,分别与HJ-1/CCD多光谱影像利用光谱锐化法(Gram-Schmidt,GS)进行融合。通过对融合影像进行质量评价,选择适合研究区冬小麦种植田块格局的适宜尺度影像。将HJ-1/CCD多光谱影像重采样,得到与适宜尺度融合影像相同尺度的影像,在两景影像中分别选取包含光谱、纹理信息的训练融合影像样本(samples of fused image,SFI)和重采样影像样本(samples of resampling image,SRI),采用面向对象分类方法对适宜尺度融合影像(fused image,FI)和重采样影像(resampling image,RI)进行冬小麦种植面积提取。结果表明,16 m×16 m融合影像的效果优于2 m×2 m、8 m×8 m和24 m×24 m融合影像,其均值、标准差、平均梯度和相关系数分别为161.15、83.01、4.55和0.97。面向对象分类后,SFI对重采样影像RI16m分类的总体精度为92.22%,Kappa系数为0.90。SFI对融合影像FI16m分类的总体精度为94.44%,Kappa系数为0.93。SRI对重采样影像RI16m分类的总体精度为84.44%,Kappa系数为0.80。SFI对融合影像FI16m分类效果最好,说明基于融合影像和融合影像提取样本(SFI)结合的面向对象分类方法能准确提取冬小麦种植面积。另外,重采样影像和融合影像提取样本(SFI)相结合的面向对象分类方法也可较好提取冬小麦种植面积。为利用国产中空间分辨率HJ-1/CCD卫星和高分1号卫星融合影像有效提取大区域冬小麦种植面积信息提供了参考。 展开更多
关键词 HJ-1/CCD卫星影像 GF-1/PMS卫星影像 冬小麦种植面积 特征提取 影像融合 面向对象分类
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‘白叶1号’异地生长鲜叶品质成分研究初探 被引量:1
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作者 王霈菲 吕杨俊 +7 位作者 宿迷菊 蒋玉兰 潘俊娴 王盈峰 赖建红 夏兵 张士康 朱跃进 《茶叶》 2024年第2期77-82,共6页
从2021年开始,项目组连续三年对安吉‘白叶1号’捐苗种植地的贵州普安、雷山、沿河,湖南古丈,四川青川三省五县和安吉原产地的茶树生长习性和品质进行跟踪研究。本文总结2023年春浙江、贵州和湖南茶鲜叶品质主要成分,按安吉白茶采摘标... 从2021年开始,项目组连续三年对安吉‘白叶1号’捐苗种植地的贵州普安、雷山、沿河,湖南古丈,四川青川三省五县和安吉原产地的茶树生长习性和品质进行跟踪研究。本文总结2023年春浙江、贵州和湖南茶鲜叶品质主要成分,按安吉白茶采摘标准采一芽二叶,分析了鲜叶中水浸出物等主要理化成分的含量以及异地生长的‘白叶1号’茶鲜叶品质差异。结果显示,2023年春茶‘白叶1号’异地与原产地鲜叶理化成分在水浸出物、游离氨基酸和茶氨酸含量方面存在显著性差异,原产地的水浸出物总量>42%,游离氨基酸含量>4.5%,茶氨酸含量>2.5%;茶苗受捐地水浸出物含量>37%,游离氨基酸含量>5.5%,茶氨酸含量>3.0%;非基地水浸出物含量>36%,游离氨基酸含量>4.0%,茶氨酸含量>1.5%。 展开更多
关键词 白叶1 异地 茶鲜叶 长势 理化成分
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顺北1号走滑断裂带分段差异活动特征及其控藏效应 被引量:1
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作者 古再丽努尔·艾尔肯 曹自成 +4 位作者 耿锋 骆福嵩 唐大卿 伍亮 王玮龙 《断块油气田》 CAS CSCD 北大核心 2024年第4期589-598,共10页
塔里木盆地塔中北坡众多大型走滑断裂带是近年油气勘探开发的重点,文中通过对顺北1号走滑断裂带三维地震资料精细解释,综合前人研究成果及油气勘探实践,探讨了顺北1号走滑断裂带的差异活动特征及其控藏效应。研究表明:1)顺北1号走滑断... 塔里木盆地塔中北坡众多大型走滑断裂带是近年油气勘探开发的重点,文中通过对顺北1号走滑断裂带三维地震资料精细解释,综合前人研究成果及油气勘探实践,探讨了顺北1号走滑断裂带的差异活动特征及其控藏效应。研究表明:1)顺北1号走滑断裂带主要发育于下古生界,为一条大型左行走滑断裂带,平面展布具有分层差异性,在下古生界为线性展布,在上古生界呈雁列式展布。2)顺北1号走滑断裂带分段差异活动特征明显,研究区内可划分出张扭、压扭和纯走滑等3类12段。3)顺北1号走滑断裂带经历了多期构造演化,其中,加里东中期Ⅰ幕、加里东中期Ⅲ幕、加里东晚期—海西早期为顺北1号走滑断裂带的关键活动时期,此后的深埋阶段构造相对稳定,断裂活动微弱。4)顺北1号走滑断裂带沟通了寒武系优质烃源岩与奥陶系有利储集体,断裂带的分段差异活动造成了不同断裂段的断溶体发育程度的差异及油藏规模的差异。实钻数据表明,张扭段和压扭段油气富集程度高,纯走滑段较低。此外,主断裂与分支断裂交叉处通常高产,推测分支断裂规模及活动强弱控制了其油气富集程度。 展开更多
关键词 差异活动 控藏效应 顺北地区 顺北1号走滑断裂带 塔里木盆地
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Angiopoietin-2/angiopoietin-1 as non-invasive biomarker of cirrhosis in chronic hepatitis C 被引量:5
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作者 ángel Hernández-Bartolomé Rosario López-Rodríguez +5 位作者 María Jesús Borque Leticia González-Moreno Yolanda Real-Martínez Luisa García-Buey Ricardo Moreno-Otero Paloma Sanz-Cameno 《World Journal of Gastroenterology》 SCIE CAS 2016年第44期9744-9751,共8页
AIM To evaluate the efficacy of peripheral blood concentrations of angiopoietins(Ang) as cirrhosis biomarkers of chronic hepatitis C(CHC).METHODS Ang1 and Ang2 serum levels were measured by enzyme-linked immunosorbent... AIM To evaluate the efficacy of peripheral blood concentrations of angiopoietins(Ang) as cirrhosis biomarkers of chronic hepatitis C(CHC).METHODS Ang1 and Ang2 serum levels were measured by enzyme-linked immunosorbent assays(ELISA) in samples from 179 cirrhotic and non-cirrhotic CHC patients, classified according to the METAVIR system.Groups were compared by non-parametric MannWhitney U test. Subsequently, the association of peripheral concentrations of angiopoietins with the stage of fibrosis was analyzed using Spearman correlation test. Finally, the accuracy, sensitivity and specificity of circulating angiopoietins for cirrhosis diagnosis were determined by the study of the respective area under the curve of receiver operator characteristics(AUC-ROC).RESULTS Peripheral blood concentrations of Ang1 and Ang2 in CHC patients were significantly related to fibrosis. While Ang1 was decreased in cirrhotic subjects compared to non-cirrhotic(P < 0.0001), Ang2 was significantly increased as CHC progressed to the end stage of liver disease(P < 0.0001). Consequently, Ang2/Ang1 ratio was notably amplified and significantly correlated with fibrosis(P < 0.0001). Interestingly, the individual performance of each angiopoietin for the diagnosis of cirrhosis reached notable AUC-ROC values(above 0.7, both), but the Ang2/Ang1 ratio was much better(AUC-ROC = 0.810) and displayed outstanding values of sensitivity(71%), specificity(84%) and accuracy(82.1%) at the optimal cut-off(10.33). Furthermore, Ang2/Ang1 ratio improved the performance of many other previously described biomarkers or scores of liver cirrhosis in CHC.CONCLUSION Ang2/Ang1 ratio might constitute a useful tool for monitoring the progression of chronic liver disease towards cirrhosis and play an important role as therapeutic target. 展开更多
关键词 Chronic hepatitis C area under the curve of receiver operator characteristics Liver fibrosis CIRRHOSIS ANGIOPOIETIN-2 ANGIOPOIETIN-1 BIOMARKER Angiogenesis
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低级别逆断层对页岩气富集高产影响研究——以四川盆地东南缘南川地区平桥东1断层为例
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作者 高全芳 张培先 +2 位作者 关琳琳 李彦婧 倪锋 《油气藏评价与开发》 CSCD 北大核心 2024年第3期458-467,共10页
南川地区位于四川盆地东南缘的复杂构造区,低级别逆断层较为发育,基于区域构造分析及构造精细解释开展逆断层形成机制及分布规律研究,并结合地震属性预测、钻井、压裂及试气试采等资料,以平桥东1断层为例,开展了低级别逆断层对页岩储集... 南川地区位于四川盆地东南缘的复杂构造区,低级别逆断层较为发育,基于区域构造分析及构造精细解释开展逆断层形成机制及分布规律研究,并结合地震属性预测、钻井、压裂及试气试采等资料,以平桥东1断层为例,开展了低级别逆断层对页岩储集性能、保存条件、压裂改造影响的分析,以揭示其对页岩气富集高产的影响。研究表明:南川地区低级别逆断层的形成主要受控于燕山中期—燕山晚期的江南—雪峰隆起的陆内造山作用的远程传导以及区域挤压应力场的变化影响,其走向整体呈北东向、北北东向,断层规模较小。平桥东1断层伴生大量天然裂缝,有效改善了储集性能,且未破坏保存条件,有利于页岩气富集成藏、地应力释放及压裂改造形成复杂缝网,实现单井高产。低级别断层附近可作为目标优选和井位部署的有利区,有效指导了复杂构造区页岩气勘探开发。 展开更多
关键词 南川地区 平桥东1断层 低级别逆断层 页岩气 富集高产
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联合Sentinel-1与Sentinel-2的高时空分辨率玉米叶面积指数反演
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作者 于慧男 王昶景 +2 位作者 刘国祥 屈永华 尹高飞 《遥感信息》 CSCD 北大核心 2024年第1期73-82,共10页
叶面积指数(leaf area index,LAI)是单位地表面积上总叶面积的一半,是影响光合作用、蒸腾作用和能量平衡等地表过程的关键生物物理变量。鉴于光学遥感数据易受天气的影响,雷达遥感数据易受土壤等的影响,二者在叶面积指数反演方面各有利... 叶面积指数(leaf area index,LAI)是单位地表面积上总叶面积的一半,是影响光合作用、蒸腾作用和能量平衡等地表过程的关键生物物理变量。鉴于光学遥感数据易受天气的影响,雷达遥感数据易受土壤等的影响,二者在叶面积指数反演方面各有利弊,提出了一种考虑不同数据反演结果不确定性的融合方法。研究测试了多种机器学习模型在中国张掖地区的玉米农田上估算LAI的性能。结果表明,光学和雷达两种数据分别作为模型输入进行LAI反演时,高斯过程回归(Gaussian process regression,GPR)的表现均为最优。随后,基于Sentinel-1雷达数据和Sentinel-2光学数据,使用GPR模型生成了研究区2019年的两种LAI及不确定性时空分布图。考虑不同数据反演结果的差异,使用加权滤波方法将两种LAI融合,实现了高时空分辨率玉米LAI制图。通过定性和定量分析,融合后的LAI时间序列分布图变化连贯,空间分布均匀,精度相较于融合之前有了明显改善。 展开更多
关键词 叶面积指数 Sentinel-1 Sentinel-2 协同 玉米
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Application Advantages of Staring Area Imaging Technology(SAIT) for Microsatellites 被引量:2
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作者 ZHONG Xing BAO Songze 《Aerospace China》 2019年第1期28-39,共12页
The Staring Area Imaging Technology(SAIT) satellite continuously "images" the target over a certain time range, and can realize continuous imaging and multi-angle imaging of the area of interest. It has the ... The Staring Area Imaging Technology(SAIT) satellite continuously "images" the target over a certain time range, and can realize continuous imaging and multi-angle imaging of the area of interest. It has the characteristics of flexible imaging parameter setting and fast image preprocessing speed, enabling dynamic target detection and tracking, super-resolution, surface 3 D model construction, night-time imaging and many other application tasks. Based on the technical characteristics of the SAIT satellite, this paper analyzes the challenges in satellite development and data processing, focuses on the quasi-realtime application of SAIT satellite data, and looks at the development trend of the SAIT satellite. 展开更多
关键词 Staring area IMAGING Technology(SAIT) Jilin-1 VIDEO SATELLITE REMOTE SENSING APPLICATION
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青砧1号/瑞香红在黄土高原不同产地果实品质差异分析
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作者 高天旭 孙鲁龙 +6 位作者 何肖肖 梁珂 龚钰博 刘振中 樊良栋 高华 赵政阳 《果树资源学报》 2024年第5期29-33,共5页
【目的】青砧1号是青岛市农业科学研究院果茶研究所培育的具有无融合生殖特性的矮化砧木,与多数品种表现出良好的亲和性与适应性,具有无支架栽培的潜力。瑞香红是西北农林科技大学选育的优质晚熟苹果新品种,为探究青砧1号/瑞香红组合在... 【目的】青砧1号是青岛市农业科学研究院果茶研究所培育的具有无融合生殖特性的矮化砧木,与多数品种表现出良好的亲和性与适应性,具有无支架栽培的潜力。瑞香红是西北农林科技大学选育的优质晚熟苹果新品种,为探究青砧1号/瑞香红组合在不同产地的栽培表现,研究以黄土高原地区4个地区的苹果园为研究对象,对主要品质性状进行分析。【方法】对甘肃庆城、渭南白水、铜川宜君、宝鸡千阳4个产区青砧1号/瑞香红的果个、果形、果实色泽和内在品质进行了差异性分析,并对不同产区青砧1号/瑞香红的果实品质进行了综合评价。【结果】结果表明,甘肃庆城地区的青砧1号/瑞香红果实综合品质较好,体现在单果质量高,果实硬度低,果面着色好以及可溶性固形物质量分数高等方面;宝鸡千阳地区的果实综合品质较差,表现为硬度大,酸度高,果面颜色暗。【结论】研究可为苹果新优品种的推广和无支架矮化栽培提供一定的参考依据和技术支持。 展开更多
关键词 苹果 瑞香红 青砧1 产地 品质
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琼东南盆地宝岛21-1区陵水组沉积特征及其油气地质意义
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作者 江汝锋 曹立成 +5 位作者 邓孝亮 何云龙 焦垚祺 陈子归 李韬 张祺 《地质科技通报》 CAS CSCD 北大核心 2024年第5期31-44,共14页
近期在琼东南盆地宝岛21-1区发现了我国首个深水深层大气田,对南海深水区深层油气勘探研究具有重要意义。基于宝岛21-1区最新获得的钻井和地震资料,分析了上渐新统陵水组三段的沉积特征及其油气地质意义。结果表明,陵三段沉积时期以双... 近期在琼东南盆地宝岛21-1区发现了我国首个深水深层大气田,对南海深水区深层油气勘探研究具有重要意义。基于宝岛21-1区最新获得的钻井和地震资料,分析了上渐新统陵水组三段的沉积特征及其油气地质意义。结果表明,陵三段沉积时期以双向物源为主,早期扇三角洲沉积发育于邻近高地,晚期辫状河三角洲沉积受NW向海南隆起物源和NE向神狐隆起物源的控制。此外,陡坡和缓坡的沉积物搬运通道表现出较大差异。陵三段沉积演化可分为3个阶段:由早期扇三角洲沉积、中期扇三角洲-辫状河三角洲沉积发展至晚期辫状河三角洲沉积,物源区也从早期邻近高地的单向供源、中期邻近高地-神狐隆起的双向供源演化至晚期海南隆起-神狐隆起的双向供源。研究区邻近崖城组烃源岩,发育12-1号断裂及伴生断裂,形成构造-岩性圈闭,成藏地质条件优越。宝岛21-1区气田的发现是我国深水油气勘探领域的重大突破,指明了海相盆地中断裂转换带是未来深水勘探的关键区域。 展开更多
关键词 琼东南盆地 宝岛21-1 陵水组 沉积特征 油气勘探
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Rapid Extraction of Water Area in Poyang Lake Based on Sentinel-1 Satellite Images
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作者 Huang Ping Xu Xiaohua Li Delong 《Meteorological and Environmental Research》 CAS 2019年第5期55-58,共4页
Based on the images taken by Sentinel-1A before and after rainstorm in Poyang Lake in June 2017,the expansion range of water area in the lake area was extracted quickly and effectively using the threshold method and v... Based on the images taken by Sentinel-1A before and after rainstorm in Poyang Lake in June 2017,the expansion range of water area in the lake area was extracted quickly and effectively using the threshold method and vector superposition method.It is proved that the method is simple and feasible,which can provide reference for the research and utilization of Sentinel-1 satellite data in the assessment of flood disaster. 展开更多
关键词 Sentinel-1 SAR Poyang LAKE Water area
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