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长滩:寂静的风景 预览
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作者 小麦 《中外书摘》 2020年第1期90-93,共4页
好像一直在忙,很久没有这样真正地放下心里的许多事,出来旅行了。地球上叫作“长滩岛”的地方其实有两个:一个是位于美国,叫“Long Beach Island”,而另一个则是菲律宾中部的一座岛屿,名为“Boraray”。
关键词 ISLAND 长滩 菲律宾
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石油沥青质分子结构模型研究进展 预览
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作者 袁梦龙 申海平 侯焕娣 《广东化工》 CAS 2020年第2期91-95,共5页
沥青质是石油中最重、结构最复杂的组分,对其分子结构的研究争议较大。目前对沥青质的分子结构认识主要有两种模型,即经典孤岛模型和群岛模型。经典孤岛模型主要由时间分辨荧光去极化、荧光相关谱法、质谱/串联质谱和直接分子成像等技... 沥青质是石油中最重、结构最复杂的组分,对其分子结构的研究争议较大。目前对沥青质的分子结构认识主要有两种模型,即经典孤岛模型和群岛模型。经典孤岛模型主要由时间分辨荧光去极化、荧光相关谱法、质谱/串联质谱和直接分子成像等技术支持,从芳香核结构、分子量等角度进行了印证。而对于群岛模型,则是由薄膜热解法、稳态荧光发射技术和质谱联用技术等提供支持,从沥青质的整体性质和稠和芳香核的核数来证明。然而沥青质分子结构的复杂性决定了其难以用一种模型来概括,而且质谱技术的结果前后不一。近年来人们更倾向于支持孤岛模型与群岛模型共存。确定孤岛-群岛结构相对比例方法的提出则为这一观点提供了强有力的证明,但这种方法仍有缺陷,如何准确地测定出孤岛-群岛结构相对比例将是未来沥青质分子结构模型的关键和难点。 展开更多
关键词 沥青质 分子结构 模型 孤岛 群岛
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Impact of GFRA1 gene reactivation by DNA demethylation on prognosis of patients with metastatic colon cancer 预览
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作者 Wan-Ru Ma Peng Xu +4 位作者 Zhao-Jun Liu Jing Zhou Lian-Kun Gu Jun Zhang Da-Jun Deng 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第2期184-198,共15页
BACKGROUND The expression of the membrane receptor protein GFRA1 is frequently upregulated in many cancers,which can promote cancer development by activating the classic RET-RAS-ERK and RET-RAS-PI3K-AKT pathways.Sever... BACKGROUND The expression of the membrane receptor protein GFRA1 is frequently upregulated in many cancers,which can promote cancer development by activating the classic RET-RAS-ERK and RET-RAS-PI3K-AKT pathways.Several therapeutic anti-GFRA1 antibody-drug conjugates are under development.Demethylation(or hypomethylation)of GFRA1 CpG islands(dmGFRA1)is associated with increased gene expression and metastasis risk of gastric cancer.However,it is unknown whether dmGFRA1 affects the metastasis of other cancers,including colon cancer(CC).AIM To study whether dmGFRA1 is a driver for CC metastasis and GFRA1 is a potential therapeutic target.METHODS CC and paired surgical margin tissue samples from 144 inpatients and normal colon mucosal biopsies from 21 noncancer patients were included in this study.The methylation status of GFRA1 islands was determined by MethyLight and denaturing high-performance liquid chromatography and bisulfite-sequencing.Kaplan-Meier analysis was used to explore the effect of dmGFRA1 on the survival of CC patients.Impacts of GFRA1 on CC cell proliferation and migration were evaluated by a battery of biological assays in vitro and in vivo.The phosphorylation of AKT and ERK proteins was examined by Western blot analysis.RESULTS The proportion of dmGFRA1 in CC,surgical margin,and normal colon tissues by MethyLight was 68.4%,73.4%,and 35.9%(median;nonparametric test,P=0.001 and<0.001),respectively.Using the median value of dmGFRA1 peak area proportion as the cutoff,the proportion of dmGFRA1-high samples was much higher in poorly differentiated CC samples than in moderately or welldifferentiated samples(92.3%%vs 55.8%,Chi-square test,P=0.002)and significantly higher in CC samples with distant metastasis than in samples without(77.8%vs 46.0%,P=0.021).The overall survival of patients with dmGFRA1-low CC was significantly longer than that of patients with dmGFRA1-high CC(adjusted hazard ratio=0.49,95%confidence interval:0.24-0.98),especially for 89 CC patients with metastatic CC(adjusted hazard ratio=0. 展开更多
关键词 GFRA1 DEMETHYLATION CpG island Colon cancer METASTASIS Membrane receptor
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海岛型乡村旅游地生态系统服务付费测度--基于二分式CVM的四种参数模型和两种非参数模型
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作者 肖建红 丁晓婷 高雪 《生态经济》 北大核心 2020年第1期131-137,177,共8页
发展海岛旅游业是实现海岛乡村振兴的重要途径,然而,海岛型乡村旅游地陆域面积狭小、生态系统脆弱,海岛旅游业可持续发展易受到威胁,需要通过政策工具来解决旅游业发展引起的环境外部性问题。论文运用单边界、双边界二分式条件价值评估... 发展海岛旅游业是实现海岛乡村振兴的重要途径,然而,海岛型乡村旅游地陆域面积狭小、生态系统脆弱,海岛旅游业可持续发展易受到威胁,需要通过政策工具来解决旅游业发展引起的环境外部性问题。论文运用单边界、双边界二分式条件价值评估法(CVM)和生态系统服务付费(PES)相结合的方法,以山东省长岛风景区为案例地,通过游客调查获取数据,运用logistic、log-logistic、normal、log-normal四种参数模型和Spearman-Karber、thesecondnon-parametric两种非参数模型,定量评估了游客对海岛型乡村旅游地生态系统服务的支付意愿。结果表明:(1)不同的分布假设,支付意愿的结果存在差异,log-logistic和log-normal分布模型比logistic和normal模分布型的拟合度更好,而log-logistic和log-normal分布模型计算出的支付意愿无明显差异;(2)参数模型与非参数模型的结果存在差异。 展开更多
关键词 乡村振兴 乡村旅游地 海岛型 生态系统服务付费 参数模型 非参数模型
被颠覆的隐喻:麻风主题的当代阐释--以希斯洛普的《岛》为核心 预览
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作者 陈倩 《武汉理工大学学报:社会科学版》 2020年第1期129-134,共6页
长期以来,麻风病的社会影响及其对应的严酷隔离制度,使之成为一个高度伦理化、政治化和历史化的文本。尽管不少西方文学作品曾涉及麻风主题,却一直未受评论界的重视。受宗教阐释学的影响,传统西方文学中麻风病人的形象基本是负面的,成为... 长期以来,麻风病的社会影响及其对应的严酷隔离制度,使之成为一个高度伦理化、政治化和历史化的文本。尽管不少西方文学作品曾涉及麻风主题,却一直未受评论界的重视。受宗教阐释学的影响,传统西方文学中麻风病人的形象基本是负面的,成为"不洁"、异类或罪恶的象征。当代英国作家希斯洛普的《岛》却有意颠覆几千年来的麻风隐喻,其以独特方式解构了健康与疾病、理性与非理性、"罪"与"赎"、"自我"与"他者"等一系列二元关系。以往研究大多关注此作的反讽手法及批判现实意识,而忽略了它对麻风隐喻义的深刻文化探讨。文章以此为例,试从宗教渊源、社会学和伦理学等角度,考察当代文学中"疾病"寓义的变迁及由此引伸出的对于"身体"、"他性"、"现代性"等问题不同于传统之反思。透过"麻风"主题,有助于我们更好地理解当代西方文学的价值转向和人文关切。 展开更多
关键词 麻风 隐喻 身体 他性 《岛》
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海岛生态物联网建设:概念和模型 预览
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作者 常立侠 张海杰 +5 位作者 张飞宇 陈昌亮 黄蓓 周厚诚 张振克 彭少麟 《生态学报》 CAS CSCD 北大核心 2019年第10期3416-3425,共10页
海岛是自然资源的重要组成部分,但由于受海洋影响强烈、海岛空间有限而生态脆弱性明显,应加强保护。保护的前提则需要掌握海岛生态本底现状及未来发展、变化趋势等信息,海岛生态物联网监测则能够为实现这一需求提供重要支撑。本文在前... 海岛是自然资源的重要组成部分,但由于受海洋影响强烈、海岛空间有限而生态脆弱性明显,应加强保护。保护的前提则需要掌握海岛生态本底现状及未来发展、变化趋势等信息,海岛生态物联网监测则能够为实现这一需求提供重要支撑。本文在前人相关研究的基础上,概述了海岛生态物联网的概念,即基于物联网技术对海岛生态系统开展自动、实时、长期监测并获取海岛生物、非生物、生态安全等信息以掌握海岛生态系统在自然和人为活动干扰下的变化规律与机制,评估海岛生态状况以作出相应决策和开展海岛生态学研究的基础网络体系;结合海岛特点构建了海岛生态物联网概念模型,形成了由生态要素监测层、数据采集层、存储层、网络传输层、能源保障层、保密层、应用层等7部分构成的监测体系;海岛生态物联网在前期构建、监测内容、数据管理、建设及维护、数据应用等方面具有区别于其他物联网的特征。以广东典型小海岛——三角岛为例展示了海岛生态物联网概念模型在具体海岛上的构建应用,为下一步开展三角岛生态物联网的实践应用及管理提供基础参考,为海岛生态监测和生态物联网建设提供理论和实践参考,并有助于未来海岛生态物联网建设的研究。 展开更多
关键词 海岛 海岛生态物联网 生态监测 概念模型
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嵊泗“跳岛游”开发思路与研究 预览
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作者 徐燕 《浙江国际海运职业技术学院学报》 2019年第1期12-15,共4页
结合国外“跳岛游”开发的经验以及嵊泗海岛实际,提出嵊泗“跳岛游”开发的基本构想,要构建“跳岛游”开发模式,提升“跳岛游”产品特色,完善“跳岛游”交通设施,建立“跳岛游”安全体系。
关键词 海岛 旅游 跳岛游 嵊泗
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基于云存储技术的海岛信息管理和展示平台设计与实现 预览
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作者 孙超 汪愿愿 +1 位作者 潘增弟 孙亚伟 《海洋通报》 CAS CSCD 北大核心 2019年第2期233-240,共8页
随着海岛遥感影像数据的不断积累,传统数据存储管理方法越来越难以满足需求。针对上述问题,利用云存储技术对海岛影像数据进行分块组织,建立分布式海岛影像数据集,并在优化数据存储的同时,设计了一套海岛信息多形式展示平台。实现了信... 随着海岛遥感影像数据的不断积累,传统数据存储管理方法越来越难以满足需求。针对上述问题,利用云存储技术对海岛影像数据进行分块组织,建立分布式海岛影像数据集,并在优化数据存储的同时,设计了一套海岛信息多形式展示平台。实现了信息检索、数据传输与审核、分析评价、成果展示和共享等功能。 展开更多
关键词 海岛 云存储 海岛影像数据 信息管理 展示平台
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Monitoring Intra-annual Spatiotemporal Changes in Urban Heat Islands in 1449 Cities in China Based on Remote Sensing 预览
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作者 LI Yuanzheng WANG Lan +2 位作者 ZHANG Liping LIU Min ZHAO Guosong 《中国地理科学:英文版》 SCIE CSCD 2019年第6期905-916,共12页
This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then... This study aimed to accurately study the intra-annual spatiotemporal variation in the surface urban heat island intensities(SUHIIs) in 1449 cities in China.First, China was divided into five environmental regions.Then, the SUHIIs were accurately calculated based on the modified definitions of the city extents and their corresponding nearby rural areas.Finally, we explored the spatiotemporal variation of the mean, maximum, and minimum values, and ranges of SUHIIs from several aspects.The results showed that larger annual mean daytime SUHIIs occurred in hot-humid South China and cold-humid northeastern China, and the smallest occurred in arid and semiarid west China.The seasonal order of the SUHIIs was summer > spring > autumn > winter in all the temperate regions except west China.The SUHIIs were obviously larger during the rainy season than the dry season in the tropical region.Nevertheless, significant differences were not observed between the two seasons within the rainy or dry periods.During the daytime, the maximum SUHIIs mostly occurred in summer in each region, while the minimum occurred in winter.A few cold island phenomena existed during the nighttime.The maximum SUHIIs were generally significantly positively correlated with the minimum SUHIIs during the daytime, nighttime and all-day in all environmental regions throughout the year and the four seasons.Moreover, significant correlation scarcely existed between the daytime and nighttime ranges of the SUHIIs.In addition, the daytime SUHIIs were also insignificantly correlated with the nighttime SUHIIs in half of the cases. 展开更多
关键词 surface urban heat island intensities(SUHIIs) land surface temperature(LST) seasonal changes maximum and minimum SUHII cold island China
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The fossil record of birds from the James Ross Basin,West Antarctica 预览
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作者 Carolina ACOSTA HOSPITALECHE Piotr JADWISZCZAK +1 位作者 Julia ACLARKE Marcos CENIZO 《极地科学进展:英文版》 CSCD 2019年第3期251-273,共23页
The fossil record of birds from Antarctica is concentrated in the James Ross Basin,located in north-east of the Antarctic Peninsula.Birds are here represented by an extensive Paleogene record of penguins(Sphenisciform... The fossil record of birds from Antarctica is concentrated in the James Ross Basin,located in north-east of the Antarctic Peninsula.Birds are here represented by an extensive Paleogene record of penguins(Sphenisciformes)and Cretaceous–Paleogene record of Anseriformes,followed by other groups with a minor representation(Procellariiformes,Falconiformes,and Pelagornithidae),and others previously assigned controversially to“Ratites”,Threskiornithidae,Charadriiformes,Gruiformes,Phoenicopteriformes,and Gaviiformes.We provide a complete update of these records,commenting on the importance of some of these remains for the evolution of the major clades. 展开更多
关键词 fossil AVIFAUNA CRETACEOUS PALEOGENE Seymour ISLAND Vega ISLAND
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海岛少儿民间体育游戏资源的开发与路径的研究——以舟山群岛为例 预览
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作者 丁曙 张同宽 《体育科技文献通报》 2019年第8期105-106,112共3页
文章运用文献资料等方法,对海岛少儿民间体育游戏进行分类和特征研究。研究表明,海岛少儿民间体育游戏具体分为运动类、模仿类、生活类和涉海类,其主要特征具有涉海性、模仿性和生活性;在开发原则上要注重游戏的科学性、教育性、针对性... 文章运用文献资料等方法,对海岛少儿民间体育游戏进行分类和特征研究。研究表明,海岛少儿民间体育游戏具体分为运动类、模仿类、生活类和涉海类,其主要特征具有涉海性、模仿性和生活性;在开发原则上要注重游戏的科学性、教育性、针对性、灵活性及游戏的安全性;在开发路径建设上要将海岛少儿民间体育游戏延伸至家庭、学校、社区、企业四位一体,使之成为促进少儿发展的第二课堂,家长、学校、社会成员成为少儿的课外老师,让少儿在社会的呵护下,得到很好的身体锻炼和意识形态方面的教育,使海岛少儿民间体育游戏得到传承。 展开更多
关键词 海岛 体育游戏 少儿 民间
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Distribution Patterns of Major and Trace Elements andProvenance of Surface Sediments on the ContinentalShelf off Western Guangdong Province andNortheastern Hainan Island 预览
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作者 GE Qian XUE Z. George +3 位作者 YE Liming XU Dong YAO Zhigang CHU Fengyou 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第4期849-858,共10页
A coupled approach based on grain size and geochemical elements is used to trace the provenance of surface sediments and to confirm the distribution patterns of grain size and elements on the continental shelf off wes... A coupled approach based on grain size and geochemical elements is used to trace the provenance of surface sediments and to confirm the distribution patterns of grain size and elements on the continental shelf off western Guangdong Province and northeastern Hainan Island. The mean grain size ranges from 0.05 φ to 7.28 φ with a mean value of 5.60 φ. The average concentra- tions of major elements descend in the order of SiO2 > Al2O3 > CaO > Fe2O3 > K2O > MgO > Na2O > TiO2 > P2O5 > MnO, while those of trace elements exhibit a descending order of Sr > Rb > Zn > V > Cr > Pb > Ni > Cu > As > Cd. On the basis of the distribution patterns of elements and results of statistical analysis, the study area is classified into three zones. Zone I locates on the continental shelf off western Guangdong Province, and the sediments are mainly from Pearl River, Taiwanese rivers, and small rivers nearby. Zone II locates in the eastern exit of Qiongzhou Strait and the coastal area off Leizhou Peninsula, and the sediments are mainly from the ero- sion products of Qiongzhou Strait and Hainan Island. Zone III locates off the eastern Hainan Island and the continental shelf deeper than 50 m isobaths, and the sediments are mainly from Hainan Island and coral reef. The influence from open water should also be considered. Results indicate that the grain size is the main controlling factor for major and trace element contents and that anthropo- genic impact and biological activity also play an important role in the distribution of these elements. 展开更多
关键词 grain size GEOCHEMICAL elements WESTERN Guangdong Province NORTHEASTERN HAINAN ISLAND controlling factor
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The fossil record of durophagous predation in the James Ross Basin over the last 125 million years 预览
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作者 Elizabeth MHARPER JAlistair CRAME Alice M PULLEN 《极地科学进展:英文版》 CSCD 2019年第3期199-209,共11页
We review the evidence for predation of shelly benthic prey over 125 million years of earth history in the James Ross Basin,Antarctica(~65°S).Although poor in the Early Cretaceous lower parts of the sequence,whic... We review the evidence for predation of shelly benthic prey over 125 million years of earth history in the James Ross Basin,Antarctica(~65°S).Although poor in the Early Cretaceous lower parts of the sequence,which represent essentially deeper water facies,evidence for both potential crushers and drillers becomes more apparent in the Santonian–Campanian Santa Marta Formation,and by the Maastrichtian López de Bertodano Formation there is an extensive fossil record of drill holes attributable to naticid gastropods,and some evidence of crushing by decapods crustaceans and possibly other taxa too.This continues at a similar level of intensity across the K/Pg boundary into the Danian Sobral Formation,but is less well constrained in the latest Paleocene–Early Eocene.The most extensive record of predation occurs in the Middle Eocene section of the La Meseta Formation on Seymour Island which also records the highest levels of benthic diversity within the entire basin.This key section is providing some important new evidence to suggest that the rate of acceleration of benthic predation intensity through the Late Mesozoic–Early Cenozoic in the polar regions may be similar to that seen in lower latitude regions.Predator–prey interaction was a key factor in the evolution of polar marine faunas too. 展开更多
关键词 drilling CRUSHING molluscs ESCALATION Seymour ISLAND
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The impact of biotic and abiotic factors on the distribution of surface sediment dinoflagellate cyst assemblages on the Nanji Island in the East China Sea 预览
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作者 Han Gao Shengpao You +3 位作者 Xiangdong Lei Yunpu Xiao Haifeng Gu Mengmeng Tong 《海洋学报:英文版》 SCIE CAS CSCD 2019年第1期160-171,共12页
The dinoflagellate cyst assemblages on the Nanji Island in the East China Sea, are documented at the first time to construct a quantitative overview of the cyst bank from 2014 to 2015. Thirty-four morphotypes from six... The dinoflagellate cyst assemblages on the Nanji Island in the East China Sea, are documented at the first time to construct a quantitative overview of the cyst bank from 2014 to 2015. Thirty-four morphotypes from six groups are identified and quantified at eight sampling sites around the island, including a high proportion of potentially toxigenic species (14%). Autotrophic dinocysts constitute 74% of the total cyst counts, which is relatively low (two to thirty-three per millilitre sediment) compared with previous studies in adjacent areas. Scrippsiella trochoidea and Protoperidinium avellana are the most abundant autotrophic and heterotrophic species, respectively. A multivariate analysis is performed to assess associations between dinocysts and abiotic or biotic variables. Differentiation among seasons is evident in the detrended correspondence analysis (DCA) ordination plot, while a spatial pattern is not clearly revealed despite heterogeneity of the hydrodynamic conditions between sampling sites. Soluble reactive phosphate, the ratio of nitrogen to phosphorus concentrations and Karenia mikimotoi bloom are the three factors significantly (P<0.05) related to surface sediment cyst assemblage defined by the canonical correspondence analysis (CCA), highlighting the importance of nutrient regime to a dinocyst distribution in this area. Although attempts to address the origin of HAB events in recent years using seed banks have failed, knowledge can be valuable for further investigation of dinocyst dynamics and potential toxin threats on the Nanji Island. 展开更多
关键词 DINOFLAGELLATE CYST Nanji ISLAND nutrients harmful ALGAL BLOOMS
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Spatiotemporal distribution of seasonal bird assemblages on land-bridge islands:linking dynamic and static views of metacommunities 预览
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作者 Chuanwu Chen Marcel Holyoak +2 位作者 Yanping Wang Xingfeng Si Ping Ding 《鸟类学研究:英文版》 CSCD 2019年第3期250-261,共12页
Background: Although assessing temporal dynamics of populations is crucial for understanding metacommunities, empirical studies have primarily analyzed only static snapshots of communities. Here, we present a holistic... Background: Although assessing temporal dynamics of populations is crucial for understanding metacommunities, empirical studies have primarily analyzed only static snapshots of communities. Here, we present a holistic view of how species traits and habitat characteristics relate to metacommunity dynamics and use it to test for differences in the spatiotemporal distribution of seasonal bird assemblages. Methods: We surveyed forest birds in breeding and winter seasons within 36 islands for 9 years. We then grouped birds into four landbird assemblages, selected on the basis of published differences in biology or ecology: winter residents, migratory winter visitors, breeding summer residents, and migratory summer visitors. We estimated dynamic species colonization and extirpation through the 9-year period, and evaluated the associations among island attributes, species attributes and community composition. Results: Overall, winter and summer residents showed strong associations between composition and habitat structure of the islands. In addition, winter and summer residents on large islands had lower extirpation and turnover than winter and summer visitors. Visitor assemblages showed no significant habitat associations, and in winter had high extirpation rates and small body sizes. By contrast, local extirpation of summer visitors was correlated with local species richness, indicating a likely effect of competition on extirpation. Conclusions: Our results demonstrated repeated patterns among species composition, bird traits, habitat/island characteristics and observed metacommunity dynamics. Winter and summer residents best matched species sorting and patch dynamics, respectively, due to differences in resource availability and requirements of overwinter survival versus breeding. Summer visitors were consistent with species sorting and winter visitors were randomly distributed, likely because of interactions with resident competitors. Our results highlight that coexisting seasonal migrant and resident assemblages di 展开更多
关键词 Body size COLONIZATION Competition EXTIRPATION Island TURNOVER METACOMMUNITY
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Cretaceous Antarctic plesiosaurs:stratigraphy,systematics and paleobiogeography 预览
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作者 Jose Patricio O’GORMAN Rodrigo OTERO +1 位作者 Marcelo REGUERO Zulma GASPARINI 《极地科学进展:英文版》 CSCD 2019年第3期210-227,共18页
The last twenty million years(Maastrichtian–Santonian)of Southern Hemisphere plesiosaur history is especially well recorded in the Weddellian Province(Patagonia;Western Antarctica and New Zealand).The oldest Late Cre... The last twenty million years(Maastrichtian–Santonian)of Southern Hemisphere plesiosaur history is especially well recorded in the Weddellian Province(Patagonia;Western Antarctica and New Zealand).The oldest Late Cretaceous plesiosaurs,two specimens referred to Polycotylidae indet.,come from the Santonian levels of the Santa Marta Formation,while the oldest elasmosaurids come from the lower Campanian of the same formation.In the lower Maastrichtian of the Snow Hill Island Formation the non-aristonectine elasmosaurid Vegasaurus molyi is recorded together with other non-diagnosable elasmosaurid specimens,but no aristonectines are present.Aristonectines appears in the Antarctic record in the upper Maastrichtian of the López de Bertodano Formation and are represented by Morturneria and cf.Aristonectes.The specimens from the upper Campanian previously referred to Aristonectinae indet.are referred to Elasmosauridae indet.,shortening the temporal record of Aristonectinae in Antarctica.Therefore aristonectines appears in the Antarctic record in the upper Maastrichtian of the López de Bertodano Formation and are represented by Morturneria and cf.Aristonectes.The Antarctic Cretaceous elasmosaurids show a paleobiogeographic connection with South America and New Zealand(Weddellian Province).This connection is indicated by the shared presence of the Aristonectinae Kaiwhekea katiki(New Zealand)and Aristonectes(Argentina and Chile).Recent phylogenetic analysis recovered the aristonectines within the Weddellonectia clade,which includes the aristonectines and the non-aristonectines Vegasaurus molyi(Isla Vega,Antarctica);Kawanectes lafquenianum(Argentina);Morenosaurus stocki and Aphrosaurus furlongi(California).Among the Weddellonectia,the aristonectines show a relatively large body size and extremely derived features and probably occupied a trophic niche that differed from the trophic niche of other elasmosaurids.By way of contrast Kawanectes lafquenianum is an extremely small body-sized elasmosaurid restricted to marginal ma 展开更多
关键词 Elasmosauridae Aristonectinae Polycotylidae SANTA Marta FORMATION Snow Hill Island FORMATION López de Bertodano FORMATION Weddellonectia
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辽西海域的海岛数量变迁研究 预览
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作者 聂鸿鹏 许鹏 《科技视界》 2019年第10期101-102,共2页
以历次海岛普查成果数据为切入点,在充分调查研究基础上通过自然因素、社会因素影响两大主线阐述了海岛数量动态变化形式,根据当前辽宁省海岛开发利用现状、以方法解读、实例剖析方式分析了海岛数量的动态变化成因,提出未来海岛数量动... 以历次海岛普查成果数据为切入点,在充分调查研究基础上通过自然因素、社会因素影响两大主线阐述了海岛数量动态变化形式,根据当前辽宁省海岛开发利用现状、以方法解读、实例剖析方式分析了海岛数量的动态变化成因,提出未来海岛数量动态变化发展趋势,加强维护海岛自然资源良性循环科持续发展的模式。 展开更多
关键词 海岛 数量 现状 变迁
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Experiments on Exploration of Shallow Fine Structures and the Construction of the 1-D Velocity Model in the Pingtan Island,Fujian 预览
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作者 GUO Yang XU Jiajun +4 位作者 LIN Chen JIN Xing YAO Huajian YANG Hongfeng CAI Huiteng 《中国地震研究:英文版》 CSCD 2019年第2期265-275,共11页
112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a den... 112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a dense array to receive the 387 airgun signals excited around the island and one month of continuous ambient noise recording.The 1-D P-wave and S-wave shallow velocity model of Pingtan Island is obtained by the inversion of the airgun body wave’s first arrival time data,and the reliability of the velocity model is verified by using the surface wave phase velocity dispersion curve,which can provide initial model for subsequent 3-D imaging.The experimental results show that this experiment is a successful demonstration of local scale green non-destructive detection,which can provide basic data for shallow surface structure research and strong vibration simulation of the Pingtan Island. 展开更多
关键词 PINGTAN ISLAND Fujian DENSE array Airgun AMBIENT noise 1-D velocity model
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《岛》中多重空间建构与人物困境探析 预览
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作者 王露苒 《信阳农林学院学报》 2019年第3期70-72,共3页
维多利亚·希斯洛普在其著作《岛》中使用了时空架构,加入文化、历史、精神和身份要素,建构了多重空间场景,再现了不同人物所遭遇的不同的困境问题,展现了20世纪初,在麻风病肆虐的背景下,主人公们的生存、伦理和精神困境,揭示空间... 维多利亚·希斯洛普在其著作《岛》中使用了时空架构,加入文化、历史、精神和身份要素,建构了多重空间场景,再现了不同人物所遭遇的不同的困境问题,展现了20世纪初,在麻风病肆虐的背景下,主人公们的生存、伦理和精神困境,揭示空间对于塑造人物小说形象的艺术效果和美感展示。维多利亚·希斯洛普在作品中最大限度地建构不同层面的空间,以展现主人公和时代困境。 展开更多
关键词 维多利亚·希斯洛普 《岛》 空间建构 人物困境
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Analysis of wave clipping effects of plain reservoir artificial islands based on MIKE21 SW model 预览
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作者 Yan Xiang Zhi-min Fu +2 位作者 Ying Meng Kai Zhang Zheng-fei Cheng 《水科学与水工程:英文版》 EI CAS CSCD 2019年第3期179-187,共9页
Plain reservoirs are shallow, and have low dams and widespread water surfaces.Therefore, wind-wave-induced damage to the dam is one of the important factors affecting the safety of the reservoir.To improve upon unsati... Plain reservoirs are shallow, and have low dams and widespread water surfaces.Therefore, wind-wave-induced damage to the dam is one of the important factors affecting the safety of the reservoir.To improve upon unsatisfactory plain reservoir wave-clipping schemes, a numerical method is proposed to predict and analyze waves in the reservoir in the presence of artificial islands, constructed from dredged sediment.The MIKE21 SW model is applied to a specific plain reservoir for finding the optimal artificial island parameters.The simulated wave height attenuation results are seen to agree well with empirically predicted values.Thus, the validity and reliability of the numerical model are established.Artificial islands at suitable locations in the reservoir can attenuate the wave heights by approximately 10%e30%, which justifies the efficacy of the clipping scheme making use of dredging and island construction. 展开更多
关键词 Plain RESERVOIRS SEDIMENT deposition CLIPPING via ISLAND construction MIKE21 SW Numerical simulation
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