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- Dupont, Samuel, 1971, et al.
(författare)
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What meta-analysis can tell us about vulnerability of marine biodiversity to ocean acidification?
- 2010
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Ingår i: Estuarine Coastal and Shelf Science. - 0272-7714. ; 89:2, s. 182-185
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Tidskriftsartikel (refereegranskat)abstract
- Ocean acidification has been proposed as a major threat for marine biodiversity. Hendriks et al. [Hendriks, I.E., Duarte, C.M., Alvarez, M., 2010. Vulnerability of marine biodiversity to ocean acidification: a meta-analysis. Estuarine, Coastal and Shelf Science, doi:10.1016/j.ecss.2009.11.022.] proposed an alternative view and suggested, based on a meta-analysis, that marine biota may be far more resistant to ocean acidification than hitherto believed. However, such a meta-analytical approach can mask more subtle features, for example differing sensitivities during the life-cycle of an organism. Using a similar metric on an echinoderm database, we show that key bottlenecks present in the life-cycle (e.g. larvae being more vulnerable than adults) and responsible for driving the whole species response may be hidden in a global meta-analysis. Our data illustrate that any ecological meta-analysis should be hypothesis driven, taking into account the complexity of biological systems, including all life-cycle stages and key biological processes. Available data allow us to conclude that near-future ocean acidification can/will have dramatic negative impact on some marine species, including echinoderms, with likely consequences at the ecosystem level. (C) 2010 Elsevier Ltd. All rights reserved.
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| 3. |
- Woldegiorgis, A., et al.
(författare)
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Matrix-assisted and polymer-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of low molecular weight polystyrenes and polyethylene glycols
- 2004
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Ingår i: Rapid Communications in Mass Spectrometry. - : Wiley. - 0951-4198 .- 1097-0231. ; 18:23, s. 2904-2912
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Tidskriftsartikel (refereegranskat)abstract
- Recently, matrices based on oligomers of dioxin and thiophene (polymer-assisted laser desorption/ionization (PALDI) have been described for mass spectrometric (MS) analysis of low molecular weight compounds (Woldegiorgis A, von Kieseritzky F, Dahlstedt E, Hellberg J, Brinck T, Roeraade J. Rapid Commun. Mass Spectrom. 2004; 18: 841-852). In this paper, we report the use of PALDI matrices for low molecular weight polymers. An evaluation with polystyrene and polyethylene glycol showed that no charge transfer ionization occurs. Ionization is mediated through metal ion adduction. Comparison of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) data for two very low molecular weight polymers with data obtained from size-exclusion chromatography (SEC) revealed a systematic difference regarding mean molecular weight and dispersity. Further, the mass spectra obtained with PALDI matrices had a higher signal-to-noise ratio than the spectra obtained with conventional matrices. For polymers with higher molecular weights (>1500 Da), the conventional matrices gave better performance. For evaluation of the MALDI spectra, three non-linear mathematical models were evaluated to model the cumulative distributions of the different oligomers and their maximal values of M-w, M-n and PDI. Models based on sigmoidal or Boltzmann equations proved to be most suitable. Objective modeling tools are necessary to compare different sample and instrumental conditions during method optimization of MALDI analysis of polymers, since the bias between MALDI and SEC data can be misleading.
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