On martingale approximations and the quenched weak invariance principle

In this paper, we obtain sufficient conditions in terms of projective criteria under which the partial sums of a stationary process with values in ${\mathcal{H}}$ (a real and separable Hilbert space) admits an approximation, in ${\mathbb{L}}^p({\mathcal{H}})$, $p>1$, by a martingale with stationary differences, and we then estimate the error of approximation in ${\mathbb{L}}^p({\mathcal{H}})$. The results are exploited to further investigate the behavior of the partial sums. In particular we obtain new projective conditions concerning the Marcinkiewicz-Zygmund theorem, the moderate deviations principle and the rates in the central limit theorem in terms of Wasserstein distances. The conditions are well suited for a large variety of examples, including linear processes or various kinds of weak dependent or mixing processes. In addition, our approach suits well to investigate the quenched central limit theorem and its invariance principle via martingale approximation, and allows us to show that they hold under the so-called Maxwell-Woodroofe condition that is known to be optimal.Comment: Published in at http://dx.doi.org/10.1214/13-AOP856 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org

Characterization of specificity of bacterial community structure within the burrow environment of the marine polychaete Hediste (Nereis) diversicolor

Bioturbation is known to stimulate microbial communities, especially in macrofaunal burrows where the abundance and activities of bacteria are increased. Until now, these microbial communities have been poorly characterized and an important ecological question remains: do burrow walls harbor similar or specific communities compared with anoxic and surface sediments? The bacterial community structure of coastal sediments inhabited by the polychaete worm Hediste diversicolor was investigated. Surface, burrow wall and anoxic sediments were collected at the Carteau beach (Gulf of Fos, Mediterranean Sea). Bacterial diversity was determined by analyzing small subunit ribosomal RNA (16S rRNA) sequences from three clone libraries (168, 179 and 129 sequences for the surface, burrow wall and anoxic sediments, respectively). Libraries revealed 306 different operational taxonomic units (OTUs) belonging to at least 15 bacterial phyla. Bioinformatic analyses and comparisons between the three clone libraries showed that the burrow walls harbored a specific bacterial community structure which differed from the surface and anoxic environments. More similarities were nevertheless found with the surface assemblage. Inside the burrow walls, the bacterial community was characterized by high biodiversity, which probably results from the biogeochemical heterogeneity of the burrow system

The EU’s New Migration Partnership with Mali: Shifting towards a Risky Security-Migration-Development Nexus. EU Diplomacy Paper 01/2018

In 2016, the European Union (EU) entered a new Migration Partnership Framework with certain priority countries. Among those priority countries, Mali is a significant case with an important presence of EU actors and missions. This paper seeks to understand why and how the EU has been redefining its migration strategy regarding Mali. The migratory context of the EU in recent years has exerted a particular political pressure on the institutional level to act. By prioritising migration, the EU is modifying an existing partnership around one element – migration – that did not constitute the primary field of cooperation in the past. This tendency to policy shift from the traditional ‘security-development nexus’ to a ‘security-migration-development nexus’ has implications for the organisation of EU actors and for the perception of Mali. As a result, the EU risks reducing its relationship with Mali to migration. This phenomenon of ‘crisis externalisation’ should not be guiding the EU’s relations with third countries, especially not with partners such as Mali, in a situation of political and territorial disruption

Initial Issues Following the Andhra Pradesh Cyclone of November 19, 1977.

Disaster Studies (Specific Disasters). (90) Asia/Indian Subcontinent/India. (802.3C)The digital Cuny Archive was made available in part through funding assistance from USAID