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Cornelia Jaspers Bastian Huwer Nancy Weiland-Bräuer Catriona Clemmesen 《Helgoland Marine Research》2018,72(1):13
Marine invasions are of increasing concern for biodiversity conservation worldwide. Gelatinous macrozooplankton contain members, which have become globally invasive, for example the ctenophore Mnemiopsis leidyi or the hydromedusae Blackfordia virginica. B. virginica is characterised by a large salinity tolerance, with a brackish-water habitat preference, and by a metagenic life history strategy with an alternation between sexually reproducing planktonic medusae and asexually reproducing benthic polyps to complete the life cycle. In this study we analysed 8 years of ichthyoplankton survey data (2010–2017) from the Kiel Canal and 14 ichthyoplankton summer surveys in the central Baltic Sea (2008–2017). We report the first presence of B. virginica in northern Europe, namely from the southwestern Baltic Sea and the Kiel Canal. In the Kiel Canal, B. virginica was first sporadically sighted in 2014 and 2015 and has developed persistent populations since summer 2016. Changes in size-frequency distributions during summer 2016 indicate active recruitment in the Kiel Canal at salinities between 7 and 13 and temperatures?>?14 °C. Close vicinity to and direct connection with the southwestern Baltic Sea, where B. virginica was observed during 2017, indicate that the Baltic Sea and other brackish-water habitats of Northern Europe are at risk for colonisation of this non-indigenous species. Our results highlight that monitoring activities should consider gelatinous macrozooplankton for standard assessments to allow for the detection of non-indigenous species at an early stage of their colonisation. 相似文献
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Brocke Hannah J. Piltz Bastian Herz Nicole Abed Raeid M. M. Palinska Katarzyna A. John Uwe Haan Joost den de Beer Dirk Nugues Maggy M. 《Coral reefs (Online)》2018,37(3):861-874
Coral Reefs - Benthic cyanobacterial mats (BCMs) have increased in abundance on coral reefs worldwide. However, their species diversity and role in nitrogen fixation are poorly understood. We... 相似文献
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Shen-Ying Zhang Nathaniel E. Clark Catherine A. Freije Elodie Pauwels Allison J. Taggart Satoshi Okada Hanna Mandel Paula Garcia Michael J. Ciancanelli Anat Biran Fabien G. Lafaille Miyuki Tsumura Aurélie Cobat Jingchuan Luo Stefano Volpi Bastian Zimmer Sonoko Sakata Alexandra Dinis Jean-Laurent Casanova 《Cell》2018,172(5):952-965.e18
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The self-association of flavin mononucleotide (FMN(2-)) as determined by (1)H NMR shift measurements
The concentration dependence of the (1)H NMR chemical upfield shifts of the protons H6, H9, H7alpha, and H8alpha of the 7,8-dimethylisoalloxazine residue of flavin mononucleotide (FMN(2-)) has been measured and the self-stacking tendency of FMN(2-) was quantified with the isodesmic model of indefinite non-cooperative self-association. The stacking tendency of FMN(2-) is considerable and described in the concentration range of 0.0025-0.1 M with the indicated model by K = 27 +/- 15 M(-1) (25 degrees C; I = 0.1-0.3 M). This result is compared with related ones from the literature. The caveats regarding the self-stacking properties of FMN(2-) and their dependence on the concentration are discussed. 相似文献
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