Paul Sabatier University

About: Paul Sabatier University is a education organization based out in Toulouse, France. It is known for research contribution in the topics: Population & Adipose tissue. The organization has 15431 authors who have published 23386 publications receiving 858364 citations.

Electrical tree initiation

Abstract: This paper reviews the recent understanding of the initiation mechanisms of electrical trees and the phenomena occurring during the induction period in the discharge free condition. The importance of charge injection in electrical tree initiation is well established, not only under dc or impulse stresses, but also under ac stress. Electroluminescence can be used as a monitor for charge injection. Tree initiation from field enhancing locations under moderate stress proceeds through cumulative degradation reactions and cavity formation caused by injected charge. The dependence of tree initiation on temperature and the nature of dissolved gases, underline the importance of free volume processes, and therefore of polymer morphology. Electron avalanche type tree initiation is strongly influenced by field modification due to space charge and also by the size of the high field region.

Using PET with 18F-AV-45 (florbetapir) to quantify brain amyloid load in a clinical environment

Abstract: Purpose Positron emission tomography (PET) imaging of brain amyloid load has been suggested as a core biomarker for Alzheimer’s disease (AD). The aim of this study was to test the feasibility of using PET imaging with 18F-AV-45 (florbetapir) in a routine clinical environment to differentiate between patients with mild to moderate AD and mild cognitive impairment (MCI) from normal healthy controls (HC).

Averting Lemur Extinctions amid Madagascar's Political Crisis

Abstract: The most threatened mammal group on Earth, Madagascar's five endemic lemur families (lemurs are found nowhere else) ( 1 ), represent more than 20% of the world's primate species and 30% of family-level diversity. This combination of diversity and uniqueness is unmatched by any other country—remarkable considering that Madagascar is only 1.3 to 2.9% the size of the Neotropics, Africa, or Asia, the other three landmasses where nonhuman primates occur. But lemurs face extinction risks driven by human disturbance of forest habitats. We discuss these challenges and reasons for hope in light of site-specific, local actions proposed in an emergency conservation action plan ( 2 ).

Inferring from Inconsistency in Preference-Based Argumentation Frameworks

Abstract: Argumentation is a promising approach to handle inconsistent knowledge bases, based on the justification of plausible conclusions by arguments. Because of inconsistency, however, arguments may be defeated by counterarguments (or defeaters). The problem is thus to select the most acceptable arguments. In this paper we investigate preference-based acceptability. The basic idea is to accept undefeated arguments and also arguments that are preferred to their defeaters. We say that these arguments defend themselves against their defeaters. We define argumentation frameworks based on that preference-based acceptability. Finally, we study associated inference relations for reasoning with inconsistent knowledge bases.

On the importance of being structured: instantaneous coalescence rates and human evolution--lessons for ancestral population size inference?

Abstract: Most species are structured and influenced by processes that either increased or reduced gene flow between populations. However, most population genetic inference methods assume panmixia and reconstruct a history characterized by population size changes. This is potentially problematic as population structure can generate spurious signals of population size change through time. Moreover, when the model assumed for demographic inference is misspecified, genomic data will likely increase the precision of misleading if not meaningless parameters. For instance, if data were generated under an n-island model (characterized by the number of islands and migrants exchanged) inference based on a model of population size change would produce precise estimates of a bottleneck that would be meaningless. In addition, archaeological or climatic events around the bottleneck's timing might provide a reasonable but potentially misleading scenario. In a context of model uncertainty (panmixia versus structure) genomic data may thus not necessarily lead to improved statistical inference. We consider two haploid genomes and develop a theory that explains why any demographic model with structure will necessarily be interpreted as a series of changes in population size by inference methods ignoring structure. We formalize a parameter, the inverse instantaneous coalescence rate, and show that it is equivalent to a population size only in panmictic models, and is mostly misleading for structured models. We argue that this issue affects all population genetics methods ignoring population structure which may thus infer population size changes that never took place. We apply our approach to human genomic data.