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Brünnich's Guillemots Uria lomvia are adapted to high-density breeding in large colonies on steep cliffs. Because they breed on narrow ledges, egg loss through dislodgement is an important cause of breeding failure. Fighting among breeders presumably raises the risk of accidental dislodgement. In this study, we investigated whether social behaviour among Brünnich's Guillemots shows any adaptations to reduce accidental egg loss by modifying behaviour during incubation. We found that the amount of aggression increased significantly at the time of hatching, perhaps in response to the reduced risk of breeding failure through dislodgement of a chick, compared with an egg. Allopreening followed an inverse trend, falling significantly after the day of hatch. This supports the hypothesis that allopreening is used to reduce aggressive interactions. At the same time, the frequency of allopreening was greatly increased on days when mosquitoes affected the birds, consistent with the hypothesis that allopreening is part of a defence strategy against ectoparasites. 相似文献
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Elisa Bellucci Orlando Mario Aguilar Saleh Alseekh Kirstin Bett Creola Brezeanu Douglas Cook Lucía De la Rosa Massimo Delledonne Denise F. Dostatny Juan J. Ferreira Valérie Geffroy Sofia Ghitarrini Magdalena Kroc Shiv Kumar Agrawal Giuseppina Logozzo Mario Marino Tristan Mary-Huard Phil McClean Vladimir Meglič Tamara Messer Frédéric Muel Laura Nanni Kerstin Neumann Filippo Servalli Silvia Străjeru Rajeev K. Varshney Marta W. Vasconcelos Massimo Zaccardelli Aleksei Zavarzin Elena Bitocchi Emanuele Frontoni Alisdair R. Fernie Tania Gioia Andreas Graner Luis Guasch Lena Prochnow Markus Oppermann Karolina Susek Maud Tenaillon Roberto Papa 《The Plant journal : for cell and molecular biology》2021,108(3):646-660
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Osei Yaw Ampomah Seyed Abdollah Mousavi Kristina Lindström Kerstin Huss-Danell 《Systematic and applied microbiology》2017,40(1):51-58
Rhizobia nodulating native Astragalus and Oxytropis spp. in Northern Europe are not well-studied. In this study, we isolated bacteria from nodules of four Astragalus spp. and two Oxytropis spp. from the arctic and subarctic regions of Sweden and Russia. The phylogenetic analyses were performed by using sequences of three housekeeping genes (16S rRNA, rpoB and recA) and two accessory genes (nodC and nifH). The results of our multilocus sequence analysis (MLSA) of the three housekeeping genes tree showed that all the 13 isolates belonged to the genus Mesorhizobium and were positioned in six clades. Our concatenated housekeeping gene tree also suggested that the isolates nodulating Astragalus inopinatus, Astragalus frigidus, Astragalus alpinus ssp. alpinus and Oxytropis revoluta might be designated as four new Mesorhizobium species. The 13 isolates were grouped in three clades in the nodC and nifH trees. 15N analysis suggested that the legumes in association with these isolates were actively fixing nitrogen. 相似文献
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Voitto Haukisalmi Alexis Ribas Kerstin Junker Andrea Spickett Sonja Matthee Heikki Henttonen Jamel Jrijer Ali Halajian Jason L. Anders Minoru Nakao 《Zoologica scripta》2018,47(2):221-230
Phylogenetic relationships, evolutionary history and systematics of tapeworms of the family Catenotaeniidae were studied using nucleotide sequences of the partial 28S nuclear rDNA (ca. 1,500 bp) and mitochondrial 12S–16S DNA (ca. 820 bp) genes. The tapeworm material consists of 29 species, including type species of the genera Catenotaenia Janicki, 1904, Catenotaenioides Haukisalmi, Hardman and Henttonen, 2010, Pseudocatenotaenia Tenora, Mas‐Coma, Murai and Feliu, 1980, Skrjabinotaenia Akhumyan, 1946, Meggittina Lynsdale, 1953, and Hemicatenotaenia Tenora, 1977. The basal phylogenetic structure of the Catenotaeniidae remains unresolved, but it is shown that most of the catenotaeniids in Eurasia and Africa comprise a large clade represented by species of Catenotaenia, Catenotaenioides, Skrjabinotaenia and Meggittina, parasitizing murid, cricetid, nesomyid and sciurid rodents. The results suggest that the divergence and early radiation of this clade have occurred in murid rodents (represented by Apodemus spp. and Mus musculus in the present material) in western Eurasia, followed by colonization of Africa, most likely independently of the colonization of their murid hosts between these continents. There is very little evidence of cophylogeny between hosts and parasites, suggesting that host transfers have played a major role in the divergence of catenotaeniids. In Africa, catenotaeniids have radiated in other murid and nesomyid rodents, and later colonized Madagascar and recolonized Eurasia. The results also show that the subfamily Skrjabinotaeniinae (including Skrjabinotaenia and Meggittina) is monophyletic, but the Catenotaeniinae (including Catenotaenia, Catenotaenioides, Pseudocatenotaenia and Hemicatenotaenia) is clearly non‐monophyletic. In addition, the genera Catenotaenia and Skrjabinotaenia were both found to be non‐monophyletic. Based on the phylogenetic and morphological evidence, several taxonomical changes, mainly new combinations, are proposed. Overall, the present results suggest that the family Catenotaeniidae is in need of major systematic revision. 相似文献
1000.
Günter Fleischer Karin Gerner Heiko Kunst Kerstin Lichtenvort Gerald Rebitzer 《The International Journal of Life Cycle Assessment》2001,6(3):149-156
Intention, Goal and Scope: Dealing with data gaps, data asymmetries, and inconsistencies in life cycle inventories (LCI) is
a general prohlem in Life Cycle Assessment (LCA) studies. An approach to deal with these difficulties is the simplification
of LCA. A methodology that lowers the requirements for data quality (accuracy) for process emissions within a simplified LCA
is introduced in this article. Background: Simplification is essential for applying LCA in the context of design for environment
(DfE). The tool euroMat is a comprehensive DfE software tool that is based on a specific, simplified LCA approach, the Iterative
Screening LCA (IS-LCA). Within the scope of the IS-LCA, there is a quantitative assessment of energy-related processes, as
well as a semi-quantitative assessment of non-energy related emissions which supplement each other. Objectives: The semi-quantitative
assessment, which is in the focus of this article, aims at lowering the requirements for the quality of non-energy related
emissions data through combined use of qualitative and quantitative inventory data. Methods: Potential environmental impacts
are assessed based on ABC-categories for qualities (harmfulness) of emissions and XYZ-categories for quantities of emitted
substances. Employing statistical methods assignment rules for the ABC/XYZ-categories were derived from literature data and
databases on emissions to air, water, and soil. Statistical tests as well as a DfE case study (comparing the materials aluminum
and carbon fiber reinforced epoxy for a lightweight container to be used in an aerospace application) were conducted in order
to evaluate the level of confidence and practicality of the proposed, simplified impact assessment. Results: Statistical and
technical consistency checks show that the method bears a high level of confidence. Results obtained by the simplified assessment
correlate to those of a detailed quantitative LCA. Conclusions: Therefore, the application of the ABC/XYZ-categories (together
with the cumulative energy demand) can be considered a practical and consistent approach for determining the environmental
significance of products when only incomplete emission data is available. Future Prospects: The statistical base of the method
is expanded continuously since it is an integral part of the DfE software tool euroMat, which is currently being further developed.
That should foster the application of the method. Outside DfE, the method should also be capable of facilitating simplified
LCAs in general. 相似文献