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1.
Biodiversity: climate change and the ecologist 总被引:2,自引:0,他引:2
Thuiller W 《Nature》2007,448(7153):550-552
2.
Consequences of climate change on the tree of life in Europe 总被引:2,自引:0,他引:2
Many species are projected to become vulnerable to twenty-first-century climate changes, with consequent effects on the tree of life. If losses were not randomly distributed across the tree of life, climate change could lead to a disproportionate loss of evolutionary history. Here we estimate the consequences of climate change on the phylogenetic diversities of plant, bird and mammal assemblages across Europe. Using a consensus across ensembles of forecasts for 2020, 2050 and 2080 and high-resolution phylogenetic trees, we show that species vulnerability to climate change clusters weakly across phylogenies. Such phylogenetic signal in species vulnerabilities does not lead to higher loss of evolutionary history than expected with a model of random extinctions. This is because vulnerable species have neither fewer nor closer relatives than the remaining clades. Reductions in phylogenetic diversity will be greater in southern Europe, and gains are expected in regions of high latitude or altitude. However, losses will not be offset by gains and the tree of life faces a trend towards homogenization across the continent. 相似文献
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4.
Wilfried Schröder 《Archive for History of Exact Sciences》1984,30(2):167-187
Ohne Zusammenfassung
Vorgelegt von
S. Flügge 相似文献
5.
Wilfried Schröder 《Archive for History of Exact Sciences》1988,39(2):157-171
Ohne Zusammenfassung
Vorgelegt von
C. Truesdell 相似文献
6.
Wilfried Schröder 《Archive for History of Exact Sciences》1982,27(4):369-389
Ohne Zusammenfassung
Vorgelegt von
S. Flügge 相似文献
7.
Jakobsson M Backman J Rudels B Nycander J Frank M Mayer L Jokat W Sangiorgi F O'Regan M Brinkhuis H King J Moran K 《Nature》2007,447(7147):986-990
Deep-water formation in the northern North Atlantic Ocean and the Arctic Ocean is a key driver of the global thermohaline circulation and hence also of global climate. Deciphering the history of the circulation regime in the Arctic Ocean has long been prevented by the lack of data from cores of Cenozoic sediments from the Arctic's deep-sea floor. Similarly, the timing of the opening of a connection between the northern North Atlantic and the Arctic Ocean, permitting deep-water exchange, has been poorly constrained. This situation changed when the first drill cores were recovered from the central Arctic Ocean. Here we use these cores to show that the transition from poorly oxygenated to fully oxygenated ('ventilated') conditions in the Arctic Ocean occurred during the later part of early Miocene times. We attribute this pronounced change in ventilation regime to the opening of the Fram Strait. A palaeo-geographic and palaeo-bathymetric reconstruction of the Arctic Ocean, together with a physical oceanographic analysis of the evolving strait and sill conditions in the Fram Strait, suggests that the Arctic Ocean went from an oxygen-poor 'lake stage', to a transitional 'estuarine sea' phase with variable ventilation, and finally to the fully ventilated 'ocean' phase 17.5 Myr ago. The timing of this palaeo-oceanographic change coincides with the onset of the middle Miocene climatic optimum, although it remains unclear if there is a causal relationship between these two events. 相似文献
8.
CH Wu C Fallini N Ticozzi PJ Keagle PC Sapp K Piotrowska P Lowe M Koppers D McKenna-Yasek DM Baron JE Kost P Gonzalez-Perez AD Fox J Adams F Taroni C Tiloca AL Leclerc SC Chafe D Mangroo MJ Moore JA Zitzewitz ZS Xu LH van den Berg JD Glass G Siciliano ET Cirulli DB Goldstein F Salachas V Meininger W Rossoll A Ratti C Gellera DA Bosco GJ Bassell V Silani VE Drory RH Brown JE Landers 《Nature》2012,488(7412):499-503
Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder resulting from motor neuron death. Approximately 10% of cases are familial (FALS), typically with a dominant inheritance mode. Despite numerous advances in recent years, nearly 50% of FALS cases have unknown genetic aetiology. Here we show that mutations within the profilin 1 (PFN1) gene can cause FALS. PFN1 is crucial for the conversion of monomeric (G)-actin to filamentous (F)-actin. Exome sequencing of two large ALS families showed different mutations within the PFN1 gene. Further sequence analysis identified 4 mutations in 7 out of 274 FALS cases. Cells expressing PFN1 mutants contain ubiquitinated, insoluble aggregates that in many cases contain the ALS-associated protein TDP-43. PFN1 mutants also display decreased bound actin levels and can inhibit axon outgrowth. Furthermore, primary motor neurons expressing mutant PFN1 display smaller growth cones with a reduced F/G-actin ratio. These observations further document that cytoskeletal pathway alterations contribute to ALS pathogenesis. 相似文献
9.
Wilfried Schröder 《Archive for History of Exact Sciences》1985,32(1):77-93
Ohne Zusammenfassung
Vorgelegt von
S. Flügge
Herrn Prof. Dr. Dr. h. c. mult. Friedrich Hund
Zur Vollendung seines 88. Geburtstages in Dankbarkeit zugeeignet 相似文献
10.
卫和平 《湖南理工学院学报:自然科学版》2006,19(2):14-18
此物质输送模型是基于系统动力学和图论建立的。模型描述的是一个包含有七个输出端口和九个时控输入端口的管系。通过Matlab Simulink动态模拟此模型后可模拟出动态输送物质过程中部件失效的影响。 相似文献