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Ehsan Rakhshani Xavier Pons Belén Lumbierres Jan Havelka Nicolás Pérez Hidalgo Željko Tomanović 《Journal of Natural History》2017,51(21-22):1237-1248
A long-term survey of tritrophic (plant–aphid–parasitoid) associations in the urban ecosystems of Lleida (Catalonia) and Paris (France) resulted in the detection of associations of two bamboo aphids, Takecallis arundinariae (Essig) and Takecallis taiwanus (Takahashi), respectively, with a new aphid parasitoid species. Trioxys remaudierei Starý & Rakhshani sp. nov. is described and illustrated as a unique parasitoid of Takecallis aphids outside the area of their origin. The new species is easily distinguishable from its congeners in having the ventral prongs of the abdomen fused over two-thirds of their length, then bifurcated towards the tip. The only morphologically similar species is Trioxys betulae (Marshall), which exhibits a clearly different prong shape (and has a different host range, Symydobius Mordvilko and Clethrobius Mordvilko). The new species is compared with allied taxa associated with bamboo aphids. The occurrence of Takecallis taiwanus on bamboo is recorded in France for the first time.
www.zoobank.org/urn:lsid:zoobank.org:pub:ED15BA16-E8A9-4CEA-BDA7-FBAB02FEB091 相似文献
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DYNAMICS OF KNOWLEDGE ACCUMULATION IN TECHNOLOGY FOLLOWER COUNTRIES: A SYSTEM DYNAMICS APPROACH 总被引:1,自引:0,他引:1
In this paper the process of knowledge accumulation for a particular technology is studied. Two countries, say the technology
follower and the technology frontier, are considered. The frontier’s knowledge growth is determined by its R&;D efforts on
the technology. The level of knowledge stock for the follower country is augmented by its R&;D activities for the technology
and absorbing some of the external knowledge through spillover from the frontier. The extent to which the follower is able
to exploit the external knowledge depends on technological gap, absorptive capacity, absorption time and degree of spillover.
New concepts such as natural and enhanced degree of spillover, background and innovative knowledge and absorption speed are
introduced in the present work to deeply explore the process of knowledge spillover. The factors influencing the knowledge
development in the long term are simultaneously studied in an integrated structure provided by the System Dynamics approach.
This framework shows the responses to the changes and provides the basis for examining the interactions among the variables
over time. 相似文献
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