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211.
Species identification of sandflies is mainly performed according to morphological characters using classical written identification keys. This study introduces a new web‐based decision support tool (sandflyDST) for guiding the morphological identification of sandfly species present in Anatolia and mainland Europe and classified in the Phlebotomus and Sergentomyia genera (both: Diptera: Psychodidae). The current version of the tool consists of 111 questions and 36 drawings obtained from classical written keys, and 107 photographs for the quick and easy identification of 26 species of the genus Phlebotomus and four species of the genus Sergentomyia. The tool guides users through a decision tree using yes/no questions about the morphological characters of the specimen. The tool was applied by 30 individuals, who then completed study questionnaires. The results of subsequent analyses indicated that the usability () and users' level of appreciation (86.6%) of the tool were quite high; almost all of the participants considered recommending the tool to others. The tool may also be useful in training new entomologists and maintaining their level of expertise. This is a dynamic tool and can be improved or upgraded according to feedback. The tool is now available online at http://parasitology.ege.edu.tr/sandflyDST/index.php .  相似文献   
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【目的】本文描述了首次在贵州猕猴桃上发生的一种害虫——端齿材小蠹Anisandrus apicalis(Blandford)。【方法】通过对当地修文县谷堡乡平滩村猕猴桃病树上小蠹的观察和形态研究,进行分类和鉴定。【结果】此次发现的端齿材小蠹是贵州省境内第一次报道,也是首次发现在猕猴桃病枝上发生。本文提供了该小蠹的分类和鉴别,附有相关近缘种的形态特征图和检索表,并介绍了其寄主和分布,以及在贵阳修文猕猴桃的危害和发生等情况。【结论】此次发生在猕猴桃上的端齿材小蠹是贵州省境内的首例,本文结果可以为当地植物检疫和猕猴桃种植管理提供参考。虽然此次端齿材小蠹在猕猴桃上发生,但是未发现其会直接为害猕猴桃健康植株,需要在将来进行深入的实验调查。  相似文献   
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齐宇  朱坦  高帅  王军锋  汲奕君  张墨  卜欣欣 《生态学报》2016,36(22):7335-7345
产业园区循环化改造是我国在"十二五"期间和今后一个时期内的一项重要工作,也是在园区层面实施循环发展的主要内容。物质流分析(MFA)是产业生态学的核心分析方法,正在成为资源环境管理领域有效的分析工具。通过梳理物质流分析方法的发展历程,指出产业园区循环化改造应用物质流分析存在注重物质规模而忽视环境影响、黑箱过程不利定量研究、小区域研究适用性不强以及隐藏流造成的数据误差等方面问题,同时通过大量调查实践,认为园区循环化改造可从企业开展清洁生产、促进园区内和园区间的产业共生、加强园区资源循环基础设施建设3个领域入手,在将园区全部企业分为生产性企业、再生性企业和资源循环基础设施企业3种类型基础上,提出关键流概念及其识别思路,探索构建物质流路径归类评价方法框架,归纳出8条典型物质流路径,为提升园区物质流管理水平提供方法依据,并选取天津经济技术开发区作为典型案例进行研究,最后对我国产业园区循环化改造应用物质流分析方法进行了展望。  相似文献   
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An analogy between the tropic interactions of insect pest-hymenopterous parasitoid and snail-larval trematode systems is proposed. The goal of most agricultural pest management programs is increase in production of a plant crop, the deleterious agent is an herbivorous insect pest, the controlling agent, a parasitoid. Other parasitoid species may or may not have a significant effect on the control of the host by the key mortality factor.In snail—schistosome systems the goal is reduction of worm burdens in human populations, removed in space and time from the snail-sporocyst interaction; the deleterious agent is the schistosome, trophically equivalent to the hymenopterous parasitoid. Therefore, control may be achieved through competitive displacement of the schistosomes by other larval trematodes having superior intrinsic competitive abilities and better searching efficiencies at low host densities.Hyperparasites, sciomyzid Diptera and Daubaylia may also play a role in this view of schistosomiasis control. The Hassell-Varley parasite quest theory is applied to larval trematodes. The inversely proportional relationship between the area of discovery and miracidial density when logarithmically transformed is further evidence for the dynamic similarity of snail-trematode and insect-parasitoid systems.Other applications of the generally accepted principles of insect pest biological control to a medically important trematode indicate that (1) schistosome population control, not eradication, is the appropriate goal of public health programs, (2) the criteria for implementation and success of such programs must be in terms of the relationship between medical injury and the frequency distribution of worms in humans, and (3) a good biological control agent is likely to have a high searching efficiency at low host densities, kill more than one snail host, be highly host specific, be scarce when successful, reside in regions were schistosomiasis is negligible as a medical problem.  相似文献   
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Abstract

Phytochemical data, integrated with other sources of information, represent a valuable tool helping to solve different kinds of taxonomic problems in plant systematics. In the present study, a comparative investigation, in order to clarify the systematic relationships of the three subspecies currently recognized within the Italian endemic Polygala flavescens, was carried out. Preliminarily, a morphometric and colorimetric analysis, in order to test the degree of morphological distinctiveness among the taxa, was performed. Then, a phytochemical analysis based both on volatile and non-volatile compounds was obtained. Concerning the morpho-colorimetric analysis, our results confirm most of the characters as useful to discriminate the three subspecies. In addition, some volatile and non-volatile compounds are good taxonomic markers. Morpho-colorimetric variation is clearly paralleled by phytochemical results, confirming the value of this kind of data to infer relationships in plant systematics. Based on these results, we support a taxonomic treatment at subspecific level for the involved taxa. Finally, based on the most significant morphological characters, a revision of herbarium specimens allowed to redefine the distribution pattern of the three subspecies. Accordingly, the range of P. flavescens subsp. maremmana is limited to Mt. Argentario (southern Tuscany) only. A key is also reported for the identification of the three subspecies.  相似文献   
217.
Two new oribatid mite species of the genus Truncozetes (Oribatida, Epactozetidae), Truncozetes ecuadoriensis sp. n. and Truncozetes monodactylus sp. n., are described from the Ecuadorian soils. The morphology of the gnathosoma and the legs is presented in detail for the first time for the species of Truncozetes. An identification key to all known species of the family Epactozetidae is given.  相似文献   
218.
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