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991.
Continuous exposure to the deterrents cis‐jasmone and methyl jasmonate does not alter the behavioural responses of Frankliniella occidentalis 下载免费PDF全文
Barbara Egger Bernhard Spangl Elisabeth Helene Koschier 《Entomologia Experimentalis et Applicata》2016,158(1):78-86
Behavioural responses of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a generalist, cell sap‐feeding insect species with piercing‐sucking mouthparts, after continuous exposure to two deterrent secondary plant compounds are investigated. We compared in choice assays on bean leaf discs, the settling, feeding, and oviposition preferences of F. occidentalis females that had no experience with the two fatty acid derivatives methyl jasmonate and cis‐jasmone before testing (naïve thrips) vs. females that had been exposed to the deterrent compounds before testing (experienced thrips). The thrips were exposed to the deterrents at low or high concentrations for varied time periods and subsequently tested on bean leaf discs treated with the respective deterrent at either a low or a high concentration. Frankliniella occidentalis females avoided settling on the deterrent‐treated bean leaf discs for an observation period of 6 h, independent of their previous experience. Our results demonstrate that feeding and oviposition deterrence of the jasmonates to the thrips were not altered by continuous exposure of the thrips to the jasmonates. Habituation was not induced, neither by exposure to the low concentration of the deterrents nor by exposure to the high concentration. These results indicate that the risk of habituation to two volatile deterrent compounds after repeated exposure is not evident in F. occidentalis. This makes the two compounds potential candidates to be integrated in pest management strategies. 相似文献
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Increasing the number of molecular markers resolves the phylogenetic relationship of ‘Cepaea’ vindobonensis (Pfeiffer 1828) with Caucasotachea Boettger 1909 (Gastropoda: Pulmonata: Helicidae) 下载免费PDF全文
Marco T. Neiber Christina Sagorny Bernhard Hausdorf 《Journal of Zoological Systematics and Evolutionary Research》2016,54(1):40-45
‘Cepaea’ vindobonensis has been shown to be closely related to Caucasotachea in recent molecular studies. The phylogenetic relationships within this clade and especially the phylogenetic position of ‘Cepaea’ vindobonensis were, however, not well resolved. Our phylogenetic analyses on the basis of an increased number of molecular genetic loci from the mitochondrial and nuclear genomes unambiguously demonstrate that ‘Cepaea’ vindobonensis represents the sister group of the Caucasotachea taxa, with C. leucoranea from the Caspian region of Azerbaijan and Iran being the sister species of the remaining Caucasian and eastern Pontic Caucasotachea species. We argue for the inclusion of ‘Cepaea’ vindobonensis in Caucasotachea rather than for a re‐erection of a monotypic genus Austrotachea for the species because of the overall low degree of morphological differentiation and the low number of species in the group. 相似文献
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Bernhard Steubing Christopher Mutel Florian Suter Stefanie Hellweg 《The International Journal of Life Cycle Assessment》2016,21(4):510-522
Purpose
The environmental performance of products or services is often a result of a number of key decisions that shape their life cycles (e.g., techology choices). This paper introduces a modular LCA approach that is capable of reducing the effort involved in performing scenario analyses and optimization when several key choices along a product’s value chain lead to many alternative life cycles.Methods
The main idea is that the value chain of a product can be divided into interconnected but exchangeable modules, which together represent a full life cycle. A module is comprised of unit processes from the practitioner’s LCI database. The inputs, outputs, and system boundaries of each module can be tailored to the context of the studied system. Alternatives arise whenever multiple modules produce substitutable products. Unlike in conventional LCI databases, no copies are necessary to represent the same process with different inputs. A module-product matrix is used to store this information. It can be used as a basis for an automated scenario analysis of all alternatives or as an input to an optimization model.Results and discussion
Our approach is illustrated in two case studies: (1) Passenger car fuel choices are modeled by 15 modules representing 33 alternative value chains for diesel, petrol, natural gas and electric cars. The automated comparison of LCA results indicates that electric mobility is often the preferable option from a climate perspective, but impacts depend strongly on the electricity source. (2) A dynamic optimization model including stocks is built from eight modules to analyze the optimal use of wood for material and energy applications. Results indicate that although direct substitution benefits are higher for energy applications, cascading use of wood can maximize environmental performance over the entire life cycle.Conclusions
The modular LCA approach permits an efficient modeling and comparison of alternative product life cycles, enabling practitioners to focus on key decisions. It can be applied to exploit a potential that is hidden in LCI databases, which is that they contain many specific inventories but not all useful combinations in the context of scenario analyses. The user-defined level of abstraction that is introduced through modules can be helpful in the communication of LCA results. The modular approach also facilitates the integration of LCA and optimization as well as other industrial ecology methods. An open source software is provided to enable others to apply and further develop our implementation of a modular LCA approach.997.
Mario P. Schimak Manuel Kleiner Silke Wetzel Manuel Liebeke Nicole Dubilier Bernhard M. Fuchs 《Applied and environmental microbiology》2016,82(1):62-70
Fluorescence in situ hybridization (FISH) has become a vital tool for environmental and medical microbiology and is commonly used for the identification, localization, and isolation of defined microbial taxa. However, fluorescence signal strength is often a limiting factor for targeting all members in a microbial community. Here, we present the application of a multilabeled FISH approach (MiL-FISH) that (i) enables the simultaneous targeting of up to seven microbial groups using combinatorial labeling of a single oligonucleotide probe, (ii) is applicable for the isolation of unfixed environmental microorganisms via fluorescence-activated cell sorting (FACS), and (iii) improves signal and imaging quality of tissue sections in acrylic resin for precise localization of individual microbial cells. We show the ability of MiL-FISH to distinguish between seven microbial groups using a mock community of marine organisms and its applicability for the localization of bacteria associated with animal tissue and their isolation from host tissues using FACS. To further increase the number of potential target organisms, a streamlined combinatorial labeling and spectral imaging-FISH (CLASI-FISH) concept with MiL-FISH probes is presented here. Through the combination of increased probe signal, the possibility of targeting hard-to-detect taxa and isolating these from an environmental sample, the identification and precise localization of microbiota in host tissues, and the simultaneous multilabeling of up to seven microbial groups, we show here that MiL-FISH is a multifaceted alternative to standard monolabeled FISH that can be used for a wide range of biological and medical applications. 相似文献
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A matter of scale: apparent niche differentiation of diploid and tetraploid plants may depend on extent and grain of analysis 下载免费PDF全文
Bernhard Kirchheimer Christoph C. F. Schinkel Agnes S. Dellinger Simone Klatt Dietmar Moser Manuela Winkler Jonathan Lenoir Marco Caccianiga Antoine Guisan Diego Nieto‐Lugilde Jens‐Christian Svenning Wilfried Thuiller Pascal Vittoz Wolfgang Willner Niklaus E. Zimmermann Elvira Hrandl Stefan Dullinger 《Journal of Biogeography》2016,43(4):716-726
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Dominic Ehrmann Nikola Bergis-Jurgan Thomas Haak Bernhard Kulzer Norbert Hermanns 《PloS one》2016,11(1)