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When parasitoids deal with the spatial distribution of their hosts: consequences for both partners

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Insect Science 2019年第5期26卷 923-931页

作者： Philippe Louapre Cecile Le lann Thierry Hance Earth and Life Institue Universite Catholique de LouvainLouvain-la-NeuveBelgium CNRS Biogeosciences UMR 6282Universite Bourgogne Franche-ComteDijonFrance UMR CNRS 6553 Ecobio University of Rennes 1Rennes CedexFrance

Insect parasitoids developing inside hosts face a true challenge: hosts are scattered in the field and their localization and selection require the use of complex and sometime confusing information. It was assumed for a long time that small-brained organisms like parasitoids have evolved simple and efficient behavioral mechanisms, leading them to be adapted to a given ecological situation, for example, the spatial distribution o f hosts in the habitat. However, hosts are not static and their distribution may also vary through generations and within the life of parasitoid individuals. We investigated if and how parasitoids deal with such a spatial com plexity in a m esocosm experiment. We used the Aphidius rhopalosiphi/Sitobion avenae parasitoid/host system to investigate if parasitoid females experiencing different host aggregation levels exhibit different foraging behaviors independently of the number of hosts in the environment. We showed that A. rhopalosiphi females exploited hosts more intensively both within and among patches at higher host aggregation levels. We discussed the adaptiveness of such behaviors in the light of evolution and biological control.

关键词： Aphidius rhopalosiphi foraging behavior parasitoid sequential adjustment Sitobion avenae spatial distribution

Intraspecific maternal competition in insect parasitoids induces summer diapause in insect parasitoids

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Insect Science 2018年第6期25卷 1080-1088页

作者： Kévin Tougeron George Hraoui Cécile Le lann Joan van Baaren Jacques Brodeur UMR-CNRS 6553Ecobio Universitéde Rennes 1RennesFrance Université Bretagne Loire Cité InternationaleRennesFrance Département de Sciences Biologiques Institut de Recherche en Biologie VegétaleUniversitéde MontréalMontréalCanada

Organisms often live in unpredictable environments and have to adopt life history strategies that optimize their fitness under these *** to bet-hedging theory,individuals can reduce variation in fitness outcomes by investing in different strategies at the same *** arthropods,facultative summer diapause enables survival during dry and hot periods of the year,and can be triggered by a decrease in resource abundance. However,the effect of resource depletion on diapause induction has never been disentangled from the effect of the perception of the presence of *** two solitary parasitoid species of cereal aphids as a model system,Aphidius avenae (Haliday)and Aphidius rhopalosiphi (De Stefani-Perez)(Hymenoptera:Braconidae),we tested whether (i)low absolute host density and/or (ii)high levels of parasitoid females'competition lead to maternal-induced summer diapause in parasitoid *** summer-like climatic conditions,emerging parasitoid females were (i)reared alone and exposed to different host densities (from 5 to 130 aphids),or (ii)reared together with competing females (from 2 to 20 females)and then exposed individually to 50 *** both parasitoid species, low aphid densities did not induce summer ***,the incidence of summer diapause increased up to a maximum of 11% with increasing levels of competition expe rienced by female *** than 60% of the females produced both diapausing and nondiapausing offspring after being kept at the two highest competition densities. Such a "spreading-the-risk"strategy has likely evolved to optimize parasitoid fitness by preventing the following generation from exposure to low populations of suitable hosts and high mortality from *** results provide the first experimental evidence of direct maternal competition-induced diapause in insects,and may change the way we apprehend the evolution of arthropod seasonal ecology,by considering intraspecific c

关键词： aestivation bet-hedging host density intraspecific competition superparasitism

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Go To The Game

初中生学习(中) 2003年第Z2期 39-40页

作者： lann

Jill: Are you ready to go to the game? Dude: Will you tell me how to bea good fan?Jill: Sure, do you have a team jersey? Dude: Just like you said; I brought the team’ s song lyrics, the sportsjersey, a sign, and a marker. Jill: ***: Why do I need all this stuff? Jill: You will see. Dude: Great, I am real excited to learnmore about sports.

关键词： Go To The Game

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看电影(初二适用)

初中生学习(中) 2003年第9期 21-24页

作者： lann

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悉尼歌剧院

初中生学习(中) 2003年第Z2期 11-12页

作者： lann

Australia’s most instantly recognized and enduring symbol , the Sydney Opera House appears to sail the harbor (海港)on billowing white wings . A world-class(世界级的)cultural center, the Opera House also hosts the city’ s symphony orchestra (交响乐队), ballet, opera and drama, and offers free concerts most Sunday afternoons along the outer walk.

关键词：悉尼歌剧院纪念品

能人政治与公共规则:业主自治何以迈向两个极端?——以上海市Y小区和S小区的比较研究为例

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甘肃行政学院学报 2021年第6期 73-84,M0007页

作者：张兰刘建军复旦大学国际关系与公共事务学院政治学系上海200433 复旦大学国际关系与公共事务学院上海200433

在社区社会主义与房权社会并存的城市社区中,以党建为代表的政治逻辑与以利益为导向的经济逻辑共同存在。那么,业委会的运作遵循什么逻辑?哪些因素制约了业主自治的走向?本文以长期追踪的上海市Y小区和S小区为例,发现两个小区面临相似... 详细信息

在社区社会主义与房权社会并存的城市社区中,以党建为代表的政治逻辑与以利益为导向的经济逻辑共同存在。那么,业委会的运作遵循什么逻辑?哪些因素制约了业主自治的走向?本文以长期追踪的上海市Y小区和S小区为例,发现两个小区面临相似的物理环境和正式化资源,但社区治理中的业委会自治却逐渐产生了分化,最终形成截然不同的结果。遵循密尔求异法中的最大相似原则,本文认为社区精英互动、业委会与物业的关系两个维度构成了业主自治的四种类型:互嵌共生、脱嵌分离、脱嵌偏轨、脱嵌失序。本文发现,党建在基层的嵌入促使社区能人利用公共规则实现了业主自治,因此党建引领下的能人政治与公共规则成为制衡业主自治的重要因素,并以此丰富奥斯特罗姆的自主治理理论。而公共规则的设计与运用促使社区精英在居民自治的过程中形成不同的策略选择,或成为业委会能人团队的“强者的工具”,或成为业主维权的“弱者的武器”。

关键词：业主自治党建引领能人政治公共规则社区精英

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俄克拉荷玛州奥尔柯盆地西部Hartshorne煤层开采及瓦斯...

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中南石油地质科技情报 1989年第2期 26-43页

作者： lann.,AT 杨爱棠

Experimental Study of Soot Volume Fraction Applied in Laminar Diffusion Flames

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Modern Mechanical Engineering 2013年第4期3卷 137-141页

作者： N. R. Caetano F. M. Pereira H. A. Vielmo F. T. van der lann Federal University of Rio Grande do Sul DEMEC-UFRGS Porto Alegre Brazil

The soot emission has been the focus of many studies due to applications in industry and the prejudicial effects caused to the environment. The presence of soot is important to the heat transfer in boilers and combustion chambers, contributing significantly to efficiency increases. In controversy, the inhaled soot may cause respiratory system damage and even cancer. Another important point is the contribution to the greenhouse effect. Therefore, the aim of this work is to analyse the soot emission in laminar diffusion flames produced from commercial fuels stabilized on a burner representative of industrial applications. Methane, vehicular natural gas and liquid petroleum gas are considered as fuels. An experimental setup was constructed to implement the technique of laser light extinction and laser-induced incandescence. These non-intrusive techniques provide instant information, in real time, about soot volume fraction. The measurements were calibrated and validated using methods and results of studies available in the literature, and also the uncertainty is analysed and suitably minimized. The results will contribute to the database for projects of combustion systems optimization, aiming to increase the efficiency and soot emissions control.

关键词： Soot Emissions Laminar Diffusion Flames Commercial Fuels

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从语域视角看网络语言

科技信息 2009年第7期 45-46页

作者：吴洪兰李华东杭州电子科技大学外国语学院浙江杭州310018

本文用语域理论分析网络语言的特点,认为网络语言是介于口语体和书面体之间的新的语体。

关键词：网络语言语域理论语场语旨语式

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