期刊文献+
共找到7,542篇文章
< 1 2 250 >
每页显示 20 50 100
An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China
1
作者 Cindy Q.Tang Min-Rui Du +10 位作者 Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol 《Plant Diversity》 SCIE CAS CSCD 2024年第5期648-660,共13页
Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understan... Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana.In this study,we investigated the impact of invasive plants on the regeneration of forests dominated by K.evelyniana,a subtropical relict species in southwestern China.For this purpose,we characterized forest dynamics of 160 forest plots featuring K.evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K.evelyniana.We identified four distinct forest types in which K.evelyniana was dominant.We found that radial growth of K.evelyniana trees is faster in younger ageclasses today than it was for older trees at the same age.The population structure of K.evelyniana in each forest type exhibited a multimodal age-class distribution.However,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina adenophora.This invasive species resulted in a reduction of understory species diversity.Additionally,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern Yunnan.This suggests closely related invasive species face heightened competition,hindering successful invasion.Taken together,our findings indicate that successful establishment and habitat restoration of K.evelyniana seedling/saplings require effective measures to control invasive plants. 展开更多
关键词 Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness
下载PDF
Detecting the distribution of and public attitudes to charismatic alien species based on media coverage
2
作者 Yuexuan Liu Ruichang Sun +1 位作者 Bo Li Zhijun Ma 《Avian Research》 SCIE CSCD 2024年第3期379-384,共6页
Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a chari... Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management. 展开更多
关键词 alien species Biological invasion Cygnus atratus Emotional tendency Invasive species Media coverage Public perception
下载PDF
The Alienation of Nature in Emily Dickinson’s Poems through the Prism of Taoism
3
作者 LI Dong-qing 《Journal of Literature and Art Studies》 2024年第3期186-193,共8页
In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dick... In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dickinson perceives nature as gentle and kind,akin to a mother.Nature is regarded as“heaven”and embodies harmony.On the other hand,nature possesses its own operational principles and harbors inherent cruelty.According to Dickinson,humans should refrain from excessive interference in the natural order.This article attempts to analyze the similarities in attitude towards nature between Dickinson’s poetry and Taoist philosophy. 展开更多
关键词 Emily Dickinson alienATION NATURE TAOISM
下载PDF
A Grotesque and Thrilling World:Alienation in The Fluted Girl
4
作者 JIN Cheng-xu 《Journal of Literature and Art Studies》 2023年第5期347-351,共5页
As a popular science fiction writer,Paolo Bacigalupi has drawn great attention with his marvelous fictions and novels,yet limited researches have focused on his novels rather than short stories,mostly analyzing from a... As a popular science fiction writer,Paolo Bacigalupi has drawn great attention with his marvelous fictions and novels,yet limited researches have focused on his novels rather than short stories,mostly analyzing from aspects like ecologism,feminism,dystopia,and anthropocene.This paper intends to analyze one of his short fictions,The Fluted Girl,using the theory of alienation to unveil the social problems hidden in the story,in order to further explore the author’s writing intention.In this grotesque and thrilling story world,Bacigalupi shows his ethical concern for the era we are living in,urging the readers to rethink about the alienation in our world. 展开更多
关键词 alienation of people alienation of consumption alienation of technology alienation of aesthetics
下载PDF
Fast tracking alien gene discovery by molecular markers in a late flowering Chinese cabbage-cabbage translocation line‘AT7–4' 被引量:1
5
作者 Hui Li Aixia Gu +12 位作者 Daling Feng Na Li Rui Yang Xinpei Zhang Shuangxia Luo Umer Karamat Qianyun Wang Shuxin Xuan Xueping Chen Yin Lu Yanhua Wang Shuxing Shen Jianjun Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期89-97,共9页
Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained seve... Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage genes.Cabbage-specific molecular markers show that these genes were coming from chromosome C01 of cabbage.In this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the offspring.Consequently,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week vernalization.Based on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were developed.This study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines. 展开更多
关键词 Chinese cabbage Translocation line alien gene Molecular marker Late flowering
下载PDF
Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City 被引量:1
6
作者 Ruchun ZHANG Hongjun JIANG +1 位作者 Henan MENG Ruijun WANG 《Plant Diseases and Pests》 CAS 2023年第4期38-43,47,共7页
[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of publi... [Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 families.In terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the total.The most alien invasive plants were native to America,accounting for 66.1%of the total.In terms of introduction path,the plants introduced artificially and unintentionally accounted for almost half.The species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and protection.There was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and protection.Among the 56 alien invasive plants,3 plants were toxic.From the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants. 展开更多
关键词 alien invasive plant Garden greenbelt Distribution characteristics Shijazhuang City Introduction path
下载PDF
Investigation and Hazard Assessment of Invasive Alien Plants on the Campus of Tongren University
7
作者 Tinghong TAN Yingying HE +4 位作者 Zide YANG Siyu XIA Li LUO Hong YANG Lan WANG 《Plant Diseases and Pests》 CAS 2023年第4期33-37,共5页
[Objectives]The paper was to investigate and assess the species,distribution and hazard status of invasive alien plants on the campus of Tongren University.[Methods]A survey was conducted using line survey method,and ... [Objectives]The paper was to investigate and assess the species,distribution and hazard status of invasive alien plants on the campus of Tongren University.[Methods]A survey was conducted using line survey method,and the risk assessment index system of invasive alien plants was established by analytic hierarchy process(AHP).[Results]There were 11 species of invasive alien plants on the campus of Tongren University,belonging to 8 genera and 5 families.There were 6 species of invasive alien plants belonging to Asteraceae,accounting for 54.55%of the total.In terms of the origin of invasive plants,most of them were native to North America and Europe,accounting for 27.27%of the total.In terms of harmful level,there were no high-risk invasive plants on the campus of Tongren University,but Alternanthera philoxeroides had the highest score and was the most harmful.[Conclusions]The present situation of alien plant invasion on the campus of Tongren University is closely related to the ecological environment of the campus.It is suggested to strengthen the management of campus plants,focus on the prevention and control of A.philoxeroides,and carry out regular investigation of invasive alien plants on campus to ensure the ecological safety of the campus. 展开更多
关键词 Tongren University Invasive alien plants Plant investigation Analytic hierarchy process Hazard assessment
下载PDF
The Alienated Plot in The End of the Road
8
作者 王丽娜 《海外英语》 2014年第19期188-190,共3页
The End of the Road is John Barth's second novel, and it is the first novel that brought abortion to the focus of public attention, which proves to be a huge success. This paper intends to study the alienation in ... The End of the Road is John Barth's second novel, and it is the first novel that brought abortion to the focus of public attention, which proves to be a huge success. This paper intends to study the alienation in The End of the Road based on the alienation as a literary style and the alienation embodied in the literary context. Through the analysis of the alienated plot, the paper aims to emphasize the internal cause for the end of the different character's road. 展开更多
关键词 The END of the ROAD alienATION the alienated PLOT
下载PDF
Using Subtracted AFLP to Efficiently Mark an Alien Chromosome Fragment in Wheat Background 被引量:7
9
作者 柴建芳 吴志明 +2 位作者 赵和 Andre LAROCHE 王海波 《Acta Botanica Sinica》 CSCD 2003年第4期379-383,共5页
为解决AFLP中样品间共同片段对多态性片段识别的干扰 ,作者建立了一种“减法AFLP”标记技术 ,并运用这种技术成功对小麦中的外源染色体片段进行了标记。运用该技术 ,样品间的共同扩增片段显著减少 ,在非变性聚丙稀酰胺凝胶上带型差异十... 为解决AFLP中样品间共同片段对多态性片段识别的干扰 ,作者建立了一种“减法AFLP”标记技术 ,并运用这种技术成功对小麦中的外源染色体片段进行了标记。运用该技术 ,样品间的共同扩增片段显著减少 ,在非变性聚丙稀酰胺凝胶上带型差异十分明显 ,多态性片段很容易分辨。其真实性通过将其中两条成功转换成外源染色体片段特异的SCAR标记得到了验证。减法AFLP标记技术的建立为标记作物中的外源染色体片段提供了一种有效手段。 展开更多
关键词 subtracted AFLP subtractive hybridization AFLP alien chromosome fragment WHEAT
下载PDF
Investigation and Risk Assessment of Alien Invasive Plants in Riparian Zone of Dongjiang River 被引量:2
10
作者 付岚 赵鸣飞 +1 位作者 龚玲 刘全儒 《Agricultural Science & Technology》 CAS 2011年第12期1897-1904,共8页
[Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling pl... [Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling plots investigation and route survey,and the whole Dongjiang River was covered.52 sampling points were set in the main streams,and 87 sampling points in tributaries streams,624 quadrats were set in total;multi-index comprehensive evaluation method was adopted for the risk assessment with 6 first-level indexes and 25 second-level indexes.[Result] Through the investigation on the riparian zone of Dongjiang River for 2 years,51 species of alien invasive plants were found,belonging to 17 families and 38 genera.The risk level assessment results of these 51 species showed that 18 species,such as Ageratum conyzoides,belonged to high-level risk with over 60 points;26 species,such as Chenopodium ambrosioides,were between 30 and 60 points which belonged to middle-level risk;7 species,such as Paspalum dilatatum,with less than 30 points belonged to low-level risk.[Conclusion] Basic data on the protection,water environmental management and functional zoning of riparian zone of Dongjiang River were provided. 展开更多
关键词 alien invasive plants Dongjiang River Risk assessment Multi-index comprehensive evaluation
下载PDF
A Study on Alien Invasive Plants from the Interactive Mechanism between Species Niche and Material/Energy Flow 被引量:3
11
作者 陈剑 喻庆国 杨宇明 《Agricultural Science & Technology》 CAS 2011年第1期14-19,共6页
[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic me... [Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants. 展开更多
关键词 Species niche Material/energy flow alien invasive plants Interactive mechanism
下载PDF
人类alien基因特性及功能的初步探讨
12
作者 彭永德 张新 +3 位作者 宋怀东 胡仁明 韩泽广 陈家伦 《第二军医大学学报》 CAS CSCD 北大核心 2001年第11期1072-1074,共3页
目的 :克隆人 alien基因全长并对其功能作初步探讨。方法 :生物信息学分析、RT- PCR、Northern印迹、GFP表达及酵母双杂交技术。结果 :从人垂体 c DNA文库中克隆到 alien的全长 c DNA,长度 196 3bp,编码 44 3aa。经搜寻 Uni Gene发现其... 目的 :克隆人 alien基因全长并对其功能作初步探讨。方法 :生物信息学分析、RT- PCR、Northern印迹、GFP表达及酵母双杂交技术。结果 :从人垂体 c DNA文库中克隆到 alien的全长 c DNA,长度 196 3bp,编码 44 3aa。经搜寻 Uni Gene发现其定位于染色体 D15 S146 - D15 S117,亚细胞定位为核内。 Northern杂交显示该基因在骨骼肌、心脏及肾脏组织为高表达。半定量 RT- PCR显示在一些内分泌组织均有表达 ,以肾上腺较高。利用酵母双杂交系统显示 alien与甲状腺激素受体 (TR)能相互作用 ,且受 T3 呈剂量依赖方式抑制。 结论 :该基因编码的产物作为一个核蛋白 ,可能参与 展开更多
关键词 alien基因 克隆 甲状腺激素受体 信号转导 基因表达
下载PDF
Genetic Analysis of Monosomic Alien Addition Line MAAL8 of O. officinalis(CC)-O. sativa(AA)
13
作者 刘如亮 刘虹 +2 位作者 陈雁 覃瑞 李刚 《Agricultural Science & Technology》 CAS 2011年第5期702-706,772,共6页
[Objective] By carrying out the anther culture on the monosomic alien addition line MAAL8 of O.officinalis-O.sativa and the back crossing with O.sativa H1493,the genetic characteristics of monosomic alien addition lin... [Objective] By carrying out the anther culture on the monosomic alien addition line MAAL8 of O.officinalis-O.sativa and the back crossing with O.sativa H1493,the genetic characteristics of monosomic alien addition line were studied.[Method] The phenotype analysis was used to study the separation proportion of progeny.Moreover,SSR and the methylation analysis were used to study the transmission behavior of nonhomologous chromosome.[Result] 78 plants of 145 backcross progenies preserved the rolled leaf mark trait of MAAL8.In 32 anther culture plants,five plants had the normal rolled leaves,and two plants had the extremely rolled leaves.The rest had the flat leaves.14 couples of SSR markers were used to analyze,and it indicated that all the rolled-leaf plants could obtain the characteristic band type of O.officinalis,but the flat-leaf plants showed none of them.11 polymorphic RFLP markers were used to carry out Methylation-Sensitive Southern analysis.It showed that the methylation variation manners of eight markers between AA and CC genomes were different.[Conclusion] The nonhomologous chromosome of MAAL8 could pass to the progenies independently and integrally via the meiosis,and the phenotype characteristics didn't change.Moreover,the methylation manner of O.officinalis could inherit stably in the hybrid progeny as the addition of single chromosome.The stability of methylation might have the certain effect on the relatively independent inheritance of nonhomologous chromosome in the genome environment of O.sativa. 展开更多
关键词 Oryza officinalis Monosomic alien addition line Anther culture Methylation variation
下载PDF
Analysis on the Epidemic Situation of Intercepted Alien Pests from Imported Hides in Hebei and the Countermeasures during 2013-2014
14
作者 王建昌 高瑞清 +2 位作者 张帅 王珅 王照华 《Agricultural Science & Technology》 CAS 2015年第9期2007-2010,共4页
The situation of intercepted alien pests from imported hides in Hebei during 2013-2014 was systematically analyzed. The results showed that 163 batches of alien pests were intercepted, including 2 batches of quarantin... The situation of intercepted alien pests from imported hides in Hebei during 2013-2014 was systematically analyzed. The results showed that 163 batches of alien pests were intercepted, including 2 batches of quarantine weeds and they both were Italian cocklebur. According to the statistics of original countries, the intercepted hides from 21 countries all had alien pests, in which Australia was the largest number of batches and species of alien pests. The analysis results showed that there was severe risk in the imported hides carrying alien pests, thus to effectively prevent the invasion of alien pests to our country, several quarantine measures should be taken in the future, such as enhancing the quarantine inspection in ports, and promoting the personnel ability of interception and species identification of alien pests. 展开更多
关键词 Imported hides alien pests Quarantine measures
下载PDF
A Review of the "Alienation" Theme in Bernard Malamud's Works
15
作者 路潇潇 《英语广场(学术研究)》 2012年第6期5-6,共2页
In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,an... In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,and The Fixer. 展开更多
关键词 alienATION Dubin’s Lives A New Life The Tenants The Fixer
下载PDF
基于Alien阅读器的RFID技术研究
16
作者 肖巍 《长春师范学院学报(自然科学版)》 2010年第6期34-37,共4页
本文以Alien阅读器为例研究RFID的相关技术,从阅读器地址查找和自主模式的电子标签阅读两个方面对Alien阅读器的阅读机制进行了深入的研究,实现了基于网络环境下对电子标签进行实时读取及监听。
关键词 RFID alien阅读器 自主模式
下载PDF
On Adaptation and Alienation in Translation
17
作者 周小惠 《海外英语》 2014年第22期173-174,共2页
From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own st... From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own strong and weak points,which leads to the conclusion that both methods are justified in their existence.And last,some points for attention are suggested for translation,which include the relationship between SL and TL,the type of texts and the translator's purpose. 展开更多
关键词 ADAPTATION alienATION TL SL
下载PDF
Alienation of the soul ,Interpretation of The love song of J. Alfred Prufrock
18
作者 LI Shun-ying 《Sino-US English Teaching》 2009年第10期39-45,共7页
The love song of J. Alfred Prufrock is known as the first masterpiece of modernism poetry. Its protagonist Prufrock is not a concrete single person, but an abstraction of all modem men in trouble. He is alienated by w... The love song of J. Alfred Prufrock is known as the first masterpiece of modernism poetry. Its protagonist Prufrock is not a concrete single person, but an abstraction of all modem men in trouble. He is alienated by women, time and space, and hence he is paralyzed and helpless. The use of dramatic monologue and stream of consciousness, quotation and allusions, objective correlative and startling imagery, irony and anti-climax, refrain and rhythm, fragmentation and juxtaposition not only deepens the theme, but also establishes Eliot's reputation as a leading modernist poet. 展开更多
关键词 The love song of J. Alfred Prufrock theme alienation of the soul techniques expressing the alienation
下载PDF
The Alienation and Loneliness in Orpheus Descending
19
作者 陈瑶琼 《海外英语》 2016年第23期164-165,共2页
Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangem... Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangement in interpersonal relations. This paper tries to analyze the solitude theme in this drama from philosophic aspect and realistic aspect, combining alienation theory and existentialism theory to analyze the reason and the manifestation of solitude. 展开更多
关键词 alienATION LONELINESS Orpheus Descending
下载PDF
Death of Children:Aloofness,Alienation and Self-Alienation in Jude the obscure
20
作者 侯立志 《海外英语》 2017年第16期156-157,164,共3页
The aim of this paper is to display Thomas Hardy's outlook on alienation in his Jude the obscure. In the deconstruction of the novel, the theme of alienation and self-alienation, together with the aloofness in soc... The aim of this paper is to display Thomas Hardy's outlook on alienation in his Jude the obscure. In the deconstruction of the novel, the theme of alienation and self-alienation, together with the aloofness in society are brought to the fore, by which Thomas Hardy's viewpoints on alienation in his philosophy of life is derived. 展开更多
关键词 alienATION SELF-alienATION Jude the obscure
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部