Search results for "extinction"

Even harmonic pulse train generation by cross-polarization-modulation seeded instability in optical fibers

2012

International audience; We show that, by properly adjusting the relative state of polarization of the pump and of a weak modulation, with a frequency such that at least one of its even harmonics falls within the band of modulation instability, one obtains a fully modulated wave at the second or higher even harmonic of the initial modulation. An application of this principle to the generation of a 80-GHz optical pulse train with high extinction ratio from a 40-GHz weakly modulated pump is experimentally demonstrated using a nonzero dispersion shifted fiber in the telecom C band.

Extinction of selected micromammal taxa during the Middle Pleistocene of Europe.

2014

The ecology of sexual conflict: Temperature variation in the social environment can drastically modulate male harm to females

2019

Sexual conflict is a fundamental driver of male/female adaptations, an engine of biodiversity and a crucial determinant of population viability. Sexual conflict frequently leads to behavioural adaptations that allow males to displace their rivals, but in doing so harm those same females they are competing to access, which can decrease population viability and facilitate extinction. We are far from understanding what factors modulate the intensity of sexual conflict and particularly the role of ecology in mediating underlying behavioural adaptations. In this study, we show that, in Drosophila melanogaster, variations in environmental temperature of ±4°C decrease male harm impact on female fi…

COMMENT TO LEHRMANN ET AL. NEW SECTIONS AND OBSERVATIONS FROM THE NANPANJIANG BASIN, SOUTH CHINA

2016

In the study of Earth-surface environmental processes during the events associated with the Permian–Triassic boundary, a key issue is the nature of the latest Permian pre-extinction surface in shallow marine limestones in numerous sites, principally within the Tethyan realm. Sediments below this surface pre-date the extinction event, so that the limestones comprising these latest Permian facies contain diverse fossil remains of organisms that lived just before the extinction. At all reported sites, this surface is disconformably overlain by post-extinction sediments, which contain microbialites in many places, particularly in Tethys. The nature of the youngest pre-extinction surface remains…

Recreational and small-scale fisheries may pose a threat to vulnerable species in coastal and offshore waters of the western Mediterranean

2019

10 pages, 3 figures, supplementary material https://doi.org/10.1093/icesjms/fsz071

A sharp estimate of the extinction time for the mean curvature flow

2007

We establish a pointwise comparison result for a nonlinear degenerate elliptic Dirichlet problem using an isoperimetric inequality involving the total mean curvature. In particular this result provides a sharp estimate for the extinction time of a class of compact surfaces, wider than the convex one, moving by mean curvature flow. Finally we present numerical experiments to compare our estimate with those known in literature.

Adapted conservation measures are required to save the Iberian lynx in a changing climate

2013

The Iberian lynx ( Lynx pardinus ) has suffered severe population declines in the twentieth century and is now on the brink of extinction 1 . Climate change could further threaten the survival of the species 2 , but its forecast effects are being neglected in recovery plans 3,4 . Quantitative estimates of extinction risk under climate change have so far mostly relied on inferences from correlative projections of species’ habitat shifts 5 . Here we use ecological niche models coupled to metapopulation simulations with source–sink dynamics 6,7 to directly investi- gate the combined effects of climate change, prey availabil- ity and management intervention on the persistence of the Iberian lyn…

Déclaration et vérification des créances. Non-renvoi d'une QPC sur l'extinction des créances non déclarées

2013

International audience; (Com., 22 mai 2013, n° 13-40.008, arrêt n° 584 F-D-QPC, Sté Generali assurance IARD c/ Philippot Chimiques, D. 2013. 1269 ; Rev. sociétés 2013. 528, obs. P. Roussel Galle ; RJDA 2013, n° 653)

Clause compromissoire. Expiration du délai de l'arbitrage. Extinction de l'instance. Obligation de constituer un nouveau tribunal arbitral. Incompéte…

1999

International audience; (Cass. 2e civ., 18 févr. 1999, inédit, Igla c/ Sté Soulier et autres)

TESTING SIMILARITY COEFFICIENTS FOR ANALYSIS OF THE FOSSIL RECORD USING CLUSTERING METHODS: THE PALAEOZOIC FLORA AS A STUDY CASE

2020

This paper reports a global methodological approach based on the similarity and clustering methods of the Palaeozoic plant fossil record using a comparative approach between two similarity measures: the Jacard and Raup-Crick Coefficients. The results show that although the Raup-Crick Coefficients clearly have the potential for providing more robust results, the consequences of the extinction processes are better reflected in the similarity analysis based on the Jaccard Coefficients. On the other hand, the cluster analysis based on UPGMA algorithm shows four robust clusters and reveals new evidence for the singularity of Mississippian flora. Finally, the results obtained reveal that similari…