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Ivonne J. Garzn‐Ordua Shaun L. Winterton Yunlan Jiang Laura C.V. Breitkreuz Peter Duelli Michael S. Engel Norman D. Penny Catherine A. Tauber Atsushi Mochizuki Xingyue Liu 《Systematic Entomology》2019,44(3):499-513
We present a time‐calibrated phylogeny of the charismatic green lacewings (Neuroptera: Chrysopidae). Previous phylogenetic studies on the family using DNA sequences have suffered from sparse taxon sampling and/or limited amounts of data. Here we combine all available previously published DNA sequence data and add to it new DNA sequences generated for this study. We analysed these data in a supermatrix using Bayesian and maximum likelihood methods and provide a phylogenetic hypothesis for the family that recovers strong support for the monophyly of all subfamilies and resolves relationships among a large proportion of chrysopine genera. Chrysopinae tribes Leucochrysini and Belonopterygini were recovered as monophyletic sister clades, while the species‐rich tribe Chrysopini was rendered paraphyletic by Ankylopterygini. Relationships among the subfamilies were resolved, although with relatively low statistical support, and the topology varied based on the method of analysis. Greatest support was found for Apochrysinae as sister to Nothochrysinae and Chrysopinae, which is in contrast to traditional concepts that place Nothochrysinae as sister to the rest of the family. Divergence estimates suggest that the stem groups to the various subfamilies diverged during the Triassic‐Jurassic, and that stem groups of the chrysopine tribes diverged during the Cretaceous. 相似文献
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Bioturbation by benthic infauna has important implications for the fate of contaminants as well as for changes to the sediment
structure, chemistry and transport characteristics. There is an extensive literature dealing with the influence of sedimentary
variables on the structure and function of infaunal marine and estuarine organisms but less is known of the converse, the
influence of biota on sedimentary structure. Although some work has been carried out regarding spatial and temporal patterns
of bioturbation, little attention has been given to the effects of pollution. The paper gives a framework of animal sediment
relationships in an intertidal environment and discusses the general role of macrofauna in structuring and modifying sedimentary
features. A brief outline of the various techniques used for quantifying the degree of bioturbation is given and some of these
techniques have then been used to demonstrate the effect of a petrochemical discharge on the bioturbation potential of intertidal
communities in the Humber estuary, eastern England. These studies indicate an increase in bioturbation with increasing distance
from the source of pollution, not only because of differences in abundance, animal size and depth of activity but also because
of the difference in species composition between the communities. As a means of interpreting the responses, the species present
have been broadly classified in terms of their feeding strategy and sediment modification potential. The paper concludes by
discussing the potential impact, in terms of effect on sediment transport, of selectively removing the different guilds (by
pollution).
Received: 8 February 1999 / Received in revised form: 10 May 1999 / Accepted: 14 May 1999 相似文献
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Timothy J. French Anthony W. Good T. Norman Palmer Mary C. Sugden 《Bioscience reports》1985,5(9):729-734
The in vivo effects of dexamethasone administration on liver and extrahepatic tissue carnitine concentrations were assessed in 48-h-starved rats. In heart and kidney, but not in liver, dexamethasone significantly increased total carnitine concentration. Acute (2.5 h) treatment with 2-tetradecylglycidate (TDG), a specific inhibitor of carnitine palmitoyl transferase 1, not only increased total hepatic carnitine concentrations, but also permitted an effect of dexamethasone (a further increase in hepatic carnitine concentration). The results are discussed in terms of acute (substrate-mediated) and chronic (hormonal) control of carnitine turnover. 相似文献
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