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Pedodiversity analysis in Hainan Island 被引量:8
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作者 ZHANGXuelei CHENJie +2 位作者 ZHANGGanlin TANManzhi J.J.Ibanez 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期181-186,共6页
Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In ... Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In this work, we have applied these techniques to use the notions such as pedodiversity (as an example of geodiversity in a broad sense), in order to detect the differences and similarities between both natural resources, biological and non-biological. The discussion has mainly been conducted through the study of landform based pedodiversity analysis applied to SOTER digital databases in Hainan Island, China. The main analytical methods include indices of richness S that are the number of the categories (SOTER units relating to different soils in this work), indices based on proportional abundance of categories H' and E which are not only the number but also their relative abundance (in our case, the relative area occupied by each pedotaxa) is taken into account, models of the distribution of abundance of categories that provide the most complete description but also the least abridged and GIS mapping to show the spatial variation digitally. 展开更多
关键词 Hainan island sOTER digital databases PEDODIVERsITY LANDFORMs abundance distribution models GIs spatial variation CLC number:s15 P208
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Screening of marine fungus from Nanji Island and activity of their metabolites against pathogenic Vibrio from Pseudosciaena crocea 被引量:1
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作者 赵淑江 李书平 +3 位作者 刘辉辉 赵倩 王杰优 闫茂仓 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第5期746-756,共11页
Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of ... Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic Vibrio from Pseudosciaena crocea. Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic Vibrio. Strain NJ0104 had the widest antimicrobial spectrum and strong activity, particularly against Fibrio parahaemolyticus-MM0810072. A preliminary study of N J0104 antibacterial metabolites demonstrated that they had thermal stability up to 80℃, ultraviolet stability up to 40 min and pH stability between 4.0-7.0. In addition, the antibacterial metabolites were readily soluble in butanol. To identify the specific strain, the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced. Based on the combination of phenotypic and genotypic data, the strain was identified as Arthrinium sp. 展开更多
关键词 Nanji island marine fungi ACTIVITY stability ITs-5.8s rDNA
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A Sm-Nd mineral isochron of mafic granulite from the Sφstrene Island, East Antarctica 被引量:1
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作者 任留东 刘小汉 《Chinese Journal of Polar Science》 1996年第2期94-98,共5页
Redetedrination of the metamorphic age of the gsrnet-bearing mafic wholeulite from the Sstrene Island, Esat Antarctica has been made and an isochron of wholerock-garnet-pyroxene-plagioclase is obtained, giving an age... Redetedrination of the metamorphic age of the gsrnet-bearing mafic wholeulite from the Sstrene Island, Esat Antarctica has been made and an isochron of wholerock-garnet-pyroxene-plagioclase is obtained, giving an age of [604±28(2σ)] Ma. Itis pointed out that this age represents the time of peak granulite facies metamorphism ofthe area. As to the geological relation of the Sstrene Island with the Bolingen Islandsand the Larsemann Hills to the east, it is deduced from the rock assemblages, metamorphic superposition, spatial changes and metamorphic ages between the above regions that the degree of the superposition of the later low pressure metamorphism is becoming stronger from west to east. While the evolution of the earlier medium pressure to later low pressure implies probably the substages of the same metamorphic cycle. 展开更多
关键词 sφstrene island metamorphic age East Antarctica granulite.
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Microhabitat use by white-footed mice Peromyscus leucopus in forested and old-field habitats occupied by Morrow's honeysuckle Lonicera morrowii
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作者 Jennifer A. EDALGO Holly M. McCHESNEY +1 位作者 Jason P. LOVE James T. ANDERSON 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第2期111-122,共12页
We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow' s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat... We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow' s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat characteristics were compared between trails used by mice ( n = 124) and randomly selected trails ( n = 127) in 4 study plots located at Fort Necessity National Battlefield, Farmington, Pennsylvania, USA. We compared 10 mierohabitat variables between used and random trails using non-metric multidimensional scaling (NMDS) and classification and regression tree (CART) analysis. Trails used by mice were statistically different from randomly selected trails in both forested plots ( P 〈 0. 008) and old-field plots ( P 〈 0. 001 ). In the forested plots, trails of white-footed mice were more often associated with a greater percent cover (% cover) of coarse woody debris (CWD) than were randomly selected trails. In the old-field plots, mouse trails were commonly characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of Morrow' s honeysuckle than randomly selected trails. Our study indicates that white-footed mice do not move randomly and prefer areas of high structural complexity, thereby showing significant microhabitat preference. The preference of white-footed mice for areas with a relatively high percent cover of Morrow's honeysuckle could 1 ) be a factor in the aggressive nature of the exotic honeysuckle shrub's spread throughout the Battlefield or 2) cause the shrub to spread even faster into adjacent areas not yet occupied by Morrow' s honeysuckle 展开更多
关键词 Microhabitat selection morrow s honeysuckle PEROMYsCUs White-footed mice Exotic species seed distribution
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Diversity and distribution of bacterioplankton in the coastal upwelling waters off Hainan Island,China
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作者 Fahui Gong Qixing Ji +2 位作者 Guihao Li Kedong Yin Jun Gong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第3期76-85,共10页
The diversity,community composition and 16 S rRNA gene abundance of bacterioplankton along a transect across an upwelling area off the eastern coast of Hainan Island(the Qiongdong upwelling)were investigated in August... The diversity,community composition and 16 S rRNA gene abundance of bacterioplankton along a transect across an upwelling area off the eastern coast of Hainan Island(the Qiongdong upwelling)were investigated in August of 2016 using high throughput sequencing and quantitative PCR assay of 16 S rRNA genes.Compared with the offshore stations,the inner-shelf stations had higher bacterial gene abundance(up to 3 fold)and operational taxonomic unit richness,a result of the influence of upwelled and fresher waters.Overall,a majority of the reads were affiliated with Gammaproteobacteria(11%-74%)and Alphaproteobacteria(14%-43%).The structure of the bacterial community was significantly affected by salinity,dissolved oxygen,NO_(3)^(-) and NH_(4)^(+),which also defined the physicochemical features of the upwelled waters.Horizontally,the relative abundances and gene abundances of Rhodobacteraceae,SAR86,Cyanobacteria and Bacteroidetes in eutrophic zone decreased from the inner to outer shelves and slope,whereas Alteromonas,Vibrio and Oceanospirillaceae exhibited an opposite trend.This study stresses the riverine influence on the oceanographic condition and spatial variability of bacterioplankton diversity and distribution in the Qiongdong upwelling. 展开更多
关键词 16s rRNA BACTERIOPLANKTON coastal upwelling Hainan island
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Invertebrate Abundance, Biomass, and Richness Associated with an Exotic Invasive Shrub (Lonicera morrowii A. Gray)
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作者 Jason P. Love James T. Anderson 《Natural Resources》 2020年第7期257-282,共26页
Exotic bush honeysuckles (</span><i><span style="font-family:Verdana;">Lonicera</span></i><span style="font-family:Verdana;"> spp.) are becoming increasingly com... Exotic bush honeysuckles (</span><i><span style="font-family:Verdana;">Lonicera</span></i><span style="font-family:Verdana;"> spp.) are becoming increasingly common in the eastern and mid-western United States, but little is known about their impacts on invertebrates. We used a modified leaf vacuum to sample invertebrates in the shrub strata and understory of three shrub types (and open plots </span><span><span style="font-family:Verdana;">in the understory): single Morrow’s honeysuckle (</span><i><span style="font-family:Verdana;">L</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">morrowii</span></i><span style="font-family:Verdana;"> A. Gray) shrubs, </span></span><span style="font-family:Verdana;">single native southern arrowwood (</span><i><span style="font-family:Verdana;">Viburnum</span></i></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">recognitum</span></i></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> Fernald) shrubs, and dense thickets of Morrow’s honeysuckle, in southwestern PA, USA during 2004 and 2005. We also assessed the degree of </span><a name="OLE_LINK26"></a><a name="OLE_LINK25"></a><span style="font-family:Verdana;">herbivory</span><span style="font-family:Verdana;"> on the two species of shrubs. Within the shrub strata, invertebrate biomass was lower in southern arrowwood shrubs, but there was no difference in invertebrate abundance or family richness. Invertebrate abundance and richness were lowest </span><span style="font-family:Verdana;">in August, but there was no difference in biomass among the months. Invertebrate</span><span style="font-family:Verdana;"> abundance, biomass, and family richness were lowest in the understory below dense thickets of Morrow’s honeysuckle. Overall, the percent cover of herbs was the proximate factor responsible for driving patterns of invertebrate abundance, though ultimately these patterns were being driven by shrub type. Abundance and biomass of larval leaf chewers were highest in the native shrub;Morrow’s honeysuckle had a mean of 29.7 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed per 1 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area, while the native shrub had a mean of 284.3 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed. Our results suggest that areas dominated by the exotic shrub negatively impact invertebrate biomass, which may in turn affect organisms at higher trophic levels. 展开更多
关键词 Invertebrate Biomass Lonicera morrowii morrow’s Honeysuckle southern Arrowwood Terrestrial Invertebrates Viburnum recognitum
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背景噪声频率-贝塞尔变换法研究厦门岛浅层S波速度结构
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作者 李海艳 陈晓非 +4 位作者 陈举庆 蔡辉腾 刘琦 冯旭平 张功恒 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2654-2667,共14页
为获取厦门岛浅层三维速度结构,本文使用福建省地震局于2019年布设的50个流动地震台站组成的密集台阵所记录到的垂向分量波形数据,计算背景噪声互相关,利用频率-贝塞尔变换(F-J)法提取子台阵的瑞利波相速度频散曲线进行反演,获取子台阵... 为获取厦门岛浅层三维速度结构,本文使用福建省地震局于2019年布设的50个流动地震台站组成的密集台阵所记录到的垂向分量波形数据,计算背景噪声互相关,利用频率-贝塞尔变换(F-J)法提取子台阵的瑞利波相速度频散曲线进行反演,获取子台阵下方一维S波速度结构,并通过插值得到厦门岛4 km以内的三维S波速度模型.结果表明,整体上厦门岛S波速度随深度增加呈现递增趋势,在近地表处的横向不均匀性显著.0~1 km深度的S波速度大体上呈现“北高南低”的特征,与岩性分布有较好的对应关系.随着深度的递增,高低速特征分布逐渐呈现为连续性较好,近北东向展布的条带状.结合前人研究结果,本文推测这一现象与厦门岛岩层在不同时期受到挤压和拉张作用形成的褶皱和断裂相关,反映了厦门岛所经历的多次构造变动和岩浆侵入事件.垂向剖面的速度差明显区与研究区断裂带位置具有一定的对应关系.研究结果可为厦门岛的构造演化研究和地质灾害评估提供新的科学依据. 展开更多
关键词 背景噪声成像 频率-贝塞尔变换法 厦门岛 浅层s波速度结构
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SVD和神经网络在孤岛检测中的应用 被引量:13
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作者 陶维青 王乐勤 +1 位作者 顾芝瑕 李嘉茜 《电力系统保护与控制》 EI CSCD 北大核心 2017年第2期28-34,共7页
针对传统被动式检测方法存在较大检测盲区(Non-detection Zone,NDZ)、阈值难以确定以及易受电能质量扰动影响的缺陷,研究了一种基于奇异值分解(Singular Value Decomposition,SVD)和神经网络的被动式孤岛检测方法。该方法首先对公共连接... 针对传统被动式检测方法存在较大检测盲区(Non-detection Zone,NDZ)、阈值难以确定以及易受电能质量扰动影响的缺陷,研究了一种基于奇异值分解(Singular Value Decomposition,SVD)和神经网络的被动式孤岛检测方法。该方法首先对公共连接点(Point of Common Coupling,PCC)处电压和逆变器输出电流进行S变换,提取相应的谐波幅值后,对其进行SVD并构成特征向量,最后运用BP神经网络对孤岛以及非孤岛情况进行分类识别。仿真结果表明,该方法可以有效检测出功率平衡情况下发生的孤岛,而且能防止电能质量扰动对检测准确性的影响,具有很高的准确性、可靠性和实用性。 展开更多
关键词 分布式发电 孤岛检测 s变换 奇异值分解 神经网络
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S变换在孤岛检测中的应用 被引量:7
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作者 青桃 江智军 《南昌大学学报(理科版)》 CAS 北大核心 2013年第1期30-33,共4页
针对光伏发电系统中传统孤岛检测方法存在的诸多缺陷,提出一种以并网点高次谐波电压为特征量的孤岛检测方法。测量并网点谐波电压,用S变换法提取测量电压中包含的高次谐波电压分量,以此分量作为孤岛识别和检测指标,无需外加扰动,即可消... 针对光伏发电系统中传统孤岛检测方法存在的诸多缺陷,提出一种以并网点高次谐波电压为特征量的孤岛检测方法。测量并网点谐波电压,用S变换法提取测量电压中包含的高次谐波电压分量,以此分量作为孤岛识别和检测指标,无需外加扰动,即可消除检测盲区。理想光伏发电并网系统进行的仿真证明,在IEEE.Std 1547规定的最差情况下,本方法进行的孤岛检测仍可快速、准确地检测到孤岛现象。 展开更多
关键词 光伏并网 孤岛检测 s变换 高次谐波 检测盲区
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内镜电凝加PPI治疗岛型及舌型SSBE疗效观察 被引量:3
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作者 侯俊 何远琴 李静娴 《现代消化及介入诊疗》 2011年第3期168-170,共3页
目的观察内镜下高频电凝加PPI治疗岛型及舌型SSBE的近中期疗效及安全性。方法经内镜及病理检查确诊的岛型及舌型SSBE病例39例,随机及自愿结合分组。23例治疗组患者在内镜下对岛型及舌型SSBE病灶施行高频电凝治疗,同时口服雷贝拉唑,20mg,... 目的观察内镜下高频电凝加PPI治疗岛型及舌型SSBE的近中期疗效及安全性。方法经内镜及病理检查确诊的岛型及舌型SSBE病例39例,随机及自愿结合分组。23例治疗组患者在内镜下对岛型及舌型SSBE病灶施行高频电凝治疗,同时口服雷贝拉唑,20mg,bid,疗程4周。16例对照组患者则单纯予雷贝拉唑口服,20mg,bid,持续抑酸治疗。分别于治疗后第3个月、6个月、12个月、18个月及24个月行胃镜随访,对照原内镜图片,观察各组岛型及舌型SSBE病灶的变化,并在原病灶处取活组织检查其病理改变。对治疗组中复查内镜未达显效者,再次行镜下电凝治疗并予雷贝拉唑口服,20mg,bid,疗程4周。结果治疗组随访病例平均显效率87.6%,总有效率100%;未出现出血、穿孔及食管狭窄等并发症。对照组平均显效率6.6%,平均总有效率26.5%,平均无效率73.5%。结论经内镜下高频电凝加PPI治疗岛型及舌型SSBE安全,近期疗效明显。 展开更多
关键词 BARRETT食管 ssBE 岛型BE 舌型BE 内镜电凝
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东南极普里兹湾Sφstrene岛麻粒岩变质年代及其与邻区的关系 被引量:6
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作者 任留东 刘小汉 《南极研究》 CSCD 1995年第3期13-17,共5页
对东南极普里兹湾Sstrene岛石榴辉石麻粒岩的变质年龄通过Sm-Nd法做了重新测定,得出604±28(2σ)Ma的石榴石-辉石-斜长石-全岩矿物内部等时线年龄,并指出本数值代表了该区主期中压麻粒岩相变质年龄。... 对东南极普里兹湾Sstrene岛石榴辉石麻粒岩的变质年龄通过Sm-Nd法做了重新测定,得出604±28(2σ)Ma的石榴石-辉石-斜长石-全岩矿物内部等时线年龄,并指出本数值代表了该区主期中压麻粒岩相变质年龄。至于与其北东部的Bolingen群岛、拉斯曼丘陵的关系,通过岩石组合,变质叠加及其空间变化特征并结合变质时代推断,自Sstrene岛至拉斯曼丘陵后期低压变质叠加逐渐增强。 展开更多
关键词 东南极 sφstrene 变质年龄 麻粒岩
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南海北部陆缘反“S”型构造带的提出及其在新生代晚期地质演化中的作用
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作者 钟建强 黄慈流 詹文欢 《台湾海峡》 CAS CSCD 1996年第2期120-126,共7页
通过地震剖面、地形-地貌、断裂构造、地壳结构、中新生代沉积盆地、第四纪地质特征等分析,认为南海北部陆缘存在滨岸岛键、陆坡北缘和陆坡南缘三条反“S”型构造带。它们形成于晚第三纪,较“新华夏系”和“南海系”晚。反“S”型构... 通过地震剖面、地形-地貌、断裂构造、地壳结构、中新生代沉积盆地、第四纪地质特征等分析,认为南海北部陆缘存在滨岸岛键、陆坡北缘和陆坡南缘三条反“S”型构造带。它们形成于晚第三纪,较“新华夏系”和“南海系”晚。反“S”型构造带新生代晚期的活动方式,对南海北部陆缘的地质演化影响显著,同时控制了这一区域的灾害性地质因素的活动方式和分布。 展开更多
关键词 构造带 南海 北部陆缘 地质演化 新生代
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InAs/GaAs系列量子点研究
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作者 王建峰 商耀辉 +2 位作者 武一宾 牛晨亮 卜夏正 《微纳电子技术》 CAS 北大核心 2009年第7期410-413,共4页
为了获得波长长、均匀性好和发光效率高的量子点,采用分子束外延(MBE)技术和S-K应变自组装模式,在GaAs(100)衬底上研究生长了三种InAs量子点。采用MBE配备的RHEED确定了工艺参数:As压维持在1.33×10-5Pa;InAs量子点和In0.2Ga0.8As... 为了获得波长长、均匀性好和发光效率高的量子点,采用分子束外延(MBE)技术和S-K应变自组装模式,在GaAs(100)衬底上研究生长了三种InAs量子点。采用MBE配备的RHEED确定了工艺参数:As压维持在1.33×10-5Pa;InAs量子点和In0.2Ga0.8As的生长温度为500℃;565℃生长50nmGaAs覆盖层。生长了垂直耦合量子点(InAs1.8ML/GaAs5nm/InAs1.8ML)、阱内量子点(In0.2Ga0.8As5nm/InAs2.4ML/In0.2Ga0.8As5nm)和柱状岛量子点(InAs分别生长1.9、1.7、1.5ML,停顿20s后,生长间隔层GaAs2nm)。测得对应的室温光致发光(PL)谱峰值波长分别为1.038、1.201、1.087μm,半峰宽为119.6、128.0、72.2nm、相对发光强度为0.034、0.153、0.29。根据PL谱的峰位、半峰宽和相对发光强与量子点波长、均匀性和发光效率的对应关系,可知量子点波长有不同程度的增加、均匀性越来越好、发光效率显著增强。 展开更多
关键词 自组装量子点 垂直耦合量子点 阱内量子点 柱状岛量子点 s-K模式 分子束外延 光致发光谱
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p16 gene methylation in colorectal cancers associated with Duke's staging 被引量:21
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作者 Jing Yi~1 Zhi-Wei Wang~1 Hui Cang~1 Yu-Ying Chen~1 Ren Zhao~2 Bao-Ming Yu~2 Xue-Ming Tang~1 1 Department of Cell Biology,2 Department of Surgery,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期722-725,共4页
AIM: To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers. METHODS: Methylation-specific P... AIM: To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers. METHODS: Methylation-specific PCR (MSP) was used to detect p16 methylation of 62 sporadic colorectal cancer specimens. RESULTS: p16 methylation was detected in 42% of the tumors.Dukes'staging was associated with p16 methylation status.p16 methylation occurred more frequently in Dukes'C and D patients (75.9%) than in Dukes'A and B patients (12.1%). CONCLUSION: p16 methylation plays a role in the carcinogenesis of a subset of colorectal cancer, and it might be linked to poor prognosis. 展开更多
关键词 DNA Methylation Colorectal Neoplasms CpG islands Female Genes p16 Humans Male Middle Aged Neoplasm staging Polymerase Chain Reaction Research support Non-U.s. Gov't
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Examining the Relationship Between Spatial Configurations of Urban Impervious Surfaces and Land Surface Temperature 被引量:3
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作者 WU Xiangli LI Binxia +3 位作者 LI Miao GUO Meixin ZANG Shuying ZHANG Shouzhi 《Chinese Geographical Science》 SCIE CSCD 2019年第4期568-578,共11页
The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), ... The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), but few of them have considered the impact of the spatial configuration of ISA on UHI. Land surface temperature(LST) may be affected not only by urban land cover, but also by neighboring land cover. The aim of this research was to investigate the effects of the abundance and spatial association of ISAs on LST. Taking Harbin City, China as an example, the impact of ISA spatial association on LST measurements was examined. The abundance of ISAs and the LST measurements were derived from Landsat Thematic Mapper(TM) imagery of 2000 and 2010, and the spatial association patterns of ISAs were calculated using the local Moran’s I index. The impacts of ISA abundance and spatial association on LST were examined using correlation analysis. The results suggested that LST has significant positive associations with both ISA abundance and the Moran’s I index of ISAs, indicating that both the abundance and spatial clustering of ISAs contribute to elevated values of LST. It was also found that LST is positively associated with clustering of high-ISA-percentage areas(i.e.,>50%) and negatively associated with clustering of low-ISA-percentage areas(i.e.,<25%). The results suggest that, in addition to the abundance of ISAs,their spatial association has a significant effect on UHIs. 展开更多
关键词 impervious surface area URBAN heat island LAND sruface temperature spatial CONFIGURATION local Moran’s I index
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Geology and Lead-Sulphur Isotope Compositions of the Tongyu Volcanic-Hosted Massive Sulphide Copper Deposit in the Western Part of the North Qinling Orogen, China 被引量:3
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作者 GONG Hujun ZHU Laimin +2 位作者 LI Ben XIONG Xiao DING Lele 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1767-1777,共11页
The Tongyu copper deposit, located in the western part of the North Qinling Orogen, China, is one of several volcanic-hosted massive sulphide(VHMS) deposits with industrial value and is also a typical example of min... The Tongyu copper deposit, located in the western part of the North Qinling Orogen, China, is one of several volcanic-hosted massive sulphide(VHMS) deposits with industrial value and is also a typical example of mineralization related to the subduction and metallogenesis during the Caledonian orogeny. We conducted systematic lead-sulphur isotope geochemical analyses of the Tongyu deposit to understand the possible ore-forming material sources and tectonic settings. Twenty-six sulphide samples yielded clustered δ^34SCDT values of 1.13‰-3.36‰, average 2.22‰, and show a tower-type distribution,implying that the sulphur of the Tongyu copper deposit mainly originated from a mantle source. The Pb isotope compositions of sulphides(^206Pb/^204Pb = 17.59225-18.56354, average 18.32020; ^207Pb/^204Pb =15.51770-15.69381, average 15.66217; ^208Pb/^204Pb= 37.99969-39.06953, average 38.52722) are close to the values of the volcanic host rocks(^206Pb/^204PbPb= 18.10678-18.26293, average 18.21158; ^207Pb/^204PbPb =15.63196-15.68188, average 15.65345; ^208Pb/^204PbPb= 38.43676-38.56360, average 38.49171), thus consistent with the Pb in ores and volcanic host rocks having been derived from a common source that was island-arc Pb related to oceanic crust subduction. The northward subduction of the Palaeo-Qinling oceanic crust triggered dehydration of the slab, which generated a large amount of high-oxygen-fugacity aqueous hydrothermal fluid. The fluid rose into the mantle wedge, activated and extracted metallogenic material and promoted partial melting of the mantle wedge. The magma and ore-forming fluid welled up and precipitated, finally forming the Tongyu VHMS copper deposit. 展开更多
关键词 VHMs-type copper deposit ore-forming material source s-Pb isotope island arc environment
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蛇岛蝮蛇(Agkistrodon qianshanensis shedaoensis)的生态观察 被引量:1
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作者 温世生 吕永通 《辽宁大学学报(自然科学版)》 CAS 1995年第4期68-71,共4页
我们从1973-1984年对辽宁蛇岛上的蝮蛇(Agkistrodonqianshanensisshedaoensis)的生态习性进行了观察。蛇岛蝮蛇的活动规律、捕食特点、繁殖习性等都适应了蛇岛的特定环境,因而得以生存... 我们从1973-1984年对辽宁蛇岛上的蝮蛇(Agkistrodonqianshanensisshedaoensis)的生态习性进行了观察。蛇岛蝮蛇的活动规律、捕食特点、繁殖习性等都适应了蛇岛的特定环境,因而得以生存至今。 展开更多
关键词 蝮蛇 活动规律 繁殖习性 生态习性 蛇岛蝮蛇
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利用R/S方法分析漯河市气温变化趋势 被引量:3
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作者 程锦霞 胡燕平 +3 位作者 惠付梅 王颖 殷广亚 董羽仑 《河南气象》 2006年第2期38-39,共2页
用一元回归和R/S方法,分析了漯河市气温变化趋势,结果表明:近49年来,漯河市冬、春、秋季气温升高,夏季则下降,夏季降温幅度比冬、春、秋季升温幅度小一个量级,全年气温整体趋势变暖。城市化“热岛”效应对冬、春、秋季及全年的影响较气... 用一元回归和R/S方法,分析了漯河市气温变化趋势,结果表明:近49年来,漯河市冬、春、秋季气温升高,夏季则下降,夏季降温幅度比冬、春、秋季升温幅度小一个量级,全年气温整体趋势变暖。城市化“热岛”效应对冬、春、秋季及全年的影响较气候系统自身演变显著,对夏季影响不显著。冬、夏、秋季及全年气温序列具有持续性,未来冬、秋季及全年变暖持续,夏季则变冷持续;春季气温变暖趋势减缓,或者更接近于随机变化,即未来变暖变冷不能确定。 展开更多
关键词 气温 热岛效应 R/s分析 HURsT指数
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Tropical Hainan——China’s Hawaii
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作者 BILL BROWN 《China Today》 2016年第10期68-69,共2页
BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan I... BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan Island,the largest island of Hainan Province,in 110 BC.Sun Yatsen recommended the establishment of a province in the region in 1906,but this did not happen until 1988,the year we moved to China. 展开更多
关键词 favorite Dynasty Tropical military China's Hawaii happen recommended until island moved
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塔里木盆地东南缘安南坝地区镁铁质麻粒岩的成因--来自地球化学及Sr-Nd-Pb同位素的制约 被引量:2
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作者 辜平阳 徐学义 +5 位作者 何世平 陈锐明 庄玉军 赵慧博 查方勇 郭亚鹏 《岩石矿物学杂志》 CAS CSCD 北大核心 2018年第5期811-823,共13页
甘肃阿克塞县安南坝地区镁铁质麻粒岩呈脉状、透镜状赋存于新太古代米兰岩群和TTG片麻岩中。岩石主要由斜长石(Pl)+斜方辉石(Opx)+单斜辉石(Cpx)+角闪石(Amp)+磁铁矿(Mt)等组成。安南坝镁铁质麻粒岩中Ti、P、Nb、Ta、Th、Hf、Sr及REE等... 甘肃阿克塞县安南坝地区镁铁质麻粒岩呈脉状、透镜状赋存于新太古代米兰岩群和TTG片麻岩中。岩石主要由斜长石(Pl)+斜方辉石(Opx)+单斜辉石(Cpx)+角闪石(Amp)+磁铁矿(Mt)等组成。安南坝镁铁质麻粒岩中Ti、P、Nb、Ta、Th、Hf、Sr及REE等元素与Zr相关性较好,表明其在变质作用过程中保持基本稳定。地球化学数据显示其原岩属于拉斑玄武质岩系列,Si O_2、Ti O_2、Al_2O_3、P_2O_5含量相对较低,Ca O、Mg O含量相对较高。Mg~#值为41.52~43.09,低于原生玄武质岩石的Mg~#值,Fe_2O_3~T、Mg O、Ca O与Si O_2含量呈负相关性,指示原岩岩浆演化过程中可能发生了辉石、角闪石等镁铁质矿物的分异结晶作用。镁铁质麻粒岩∑REE较低,稀土元素配分模式为轻稀土元素弱富集、重稀土元素相对平坦的右倾型,Eu异常不明显(Eu/Eu~*=0.91~1.01)。岩石富集Rb、Ba、Sr等大离子亲石元素,亏损Nb、Ta、Zr、Ti等高场强元素,具有显生宙典型岛弧玄武质岩石的地球化学特征。Sr、Nd、Pb同位素组成显示镁铁质麻粒岩原岩源自富集地幔,并受到一定程度的地壳物质混染。构造环境分析表明安南坝镁铁质麻粒岩原岩形成于与俯冲有关的岛弧环境。在俯冲作用机制下,俯冲板片流体交代使地幔楔发生富集,形成富集地幔,随着(弧后)伸展作用的加强,进一步诱发富集地幔的部分熔融形成镁铁质岩浆,最终岩浆就位形成辉长岩或辉绿岩脉,后期在麻粒岩相变质作用条件下变质为镁铁质麻粒岩。 展开更多
关键词 镁铁质麻粒岩 地球化学 sR-ND-PB同位素 安南坝地区 塔里木东南缘
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