Universal long-time properties of Lagrangian statistics in the Batchelor regime and their application to the passive scalar problem

We consider transport of dynamically passive quantities in the Batchelor regime of smooth in space velocity field. For the case of arbitrary temporal correlations of the velocity we formulate the statistics of relevant characteristics of Lagrangian motion. This allows to generalize many results obtained previously for the delta-correlated in time strain, thus answering the question of universality of these results.Comment: 11 pages, revtex; added references, typos correcte

Dispersion and collapse in stochastic velocity fields on a cylinder

The dynamics of fluid particles on cylindrical manifolds is investigated. The velocity field is obtained by generalizing the isotropic Kraichnan ensemble, and is therefore Gaussian and decorrelated in time. The degree of compressibility is such that when the radius of the cylinder tends to infinity the fluid particles separate in an explosive way. Nevertheless, when the radius is finite the transition probability of the two-particle separation converges to an invariant measure. This behavior is due to the large-scale compressibility generated by the compactification of one dimension of the space

A Framework for Verifying Data-Centric Protocols

International audienceData centric languages, such as recursive rule based languages, have been proposed to program distributed applications over networks. They simplify greatly the code, while still admitting efficient distributed execution. We show that they also provide a promising approach to the verification of distributed protocols, thanks to their data centric orientation, which allows us to explicitly handle global structures such as the topology of the network. We consider a framework using an original formalization in the Coq proof assistant of a distributed computation model based on message passing with either synchronous or asynchronous behavior. The declarative rules of the Netlog language for specifying distributed protocols and the virtual machines for evaluating these rules are encoded in Coq as well. We consider as a case study tree protocols, and show how this framework enables us to formally verify them in both the asynchronous and synchronous setting

Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD 104237

Astronomy and Astrophysics, 464, pp. 55-58, http://dx.doi.org./10.1051/0004-6361:20065719International audienc

Self-Reports and Caregivers’ Proxy Reports of Unmet Needs of Persons With Dementia: Implications for Both Partners’ Health-Related Quality of Life

Objective This study examined in a large sample of dementia caregiving dyads the associations between both partners’ reports of unmet needs in persons with dementia (PwDs) and both partners’ health-related quality of life (HRQOL).  Methods This was a cross-sectional self-report survey of 521 community-dwelling dyads in a pragmatic trial in the Netherlands. The Camberwell Needs Assessment was used to measure PwDs’ unmet needs. Both partners’ self-reported their HRQOL using the EuroQol-5. Results Controlling for covariates, PwDs’ self-reported greater unmet needs were significantly associated with PwDs’ and caregivers’ lower self-reported HRQOL (actor effect; b = −0.044, β = −0.226, z = −3.588, p <0.001 and partner effect; b = −0.021, β = −0.131, z = −2.154, p = 0.031). Caregivers’ proxy reports were greater than PwDs’ self-reported unmet needs.  Conclusion Clinicians should use caution in relying on caregiver proxy reports of PwDs’ needs and HQOL alone regarding healthcare decision making

Effects of initial pH on compositional changes and sensory traits of french dry-cured hams

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Alkylated phenanthrene distribution in artificially matured kerogens from Kimmeridge clay and the Brent Formation (North Sea)

Kerogen and extractible organic matter from immature Kimmeridge clay and Brent coal were heated at different temperatures (270-500°C) under conditions to mimic natural maturation. Aromatic fractions have been examined for their phenanthrene compound distribution. Phenanthrene indices based on methylphenanthrenes (MP) and dimethylphenanthrenes (DMP) exhibit very sensible changes in the applied temperature range. However, at high temperatures (about 450°C and more) possible thermal degradation of phenanthrene compounds produces a decrease in the values of the indices. Experimental data obtained in this study are compared and discussed with data obtained on thermal evolution performed on total rocks. Vitrinite reflectance values measured on artificially matured coals are also tentatively correlated with phenanthrene ratios. Theoretical thermodynamic calculations on MP compounds confirm also the relative thermal stability of the individual isomers. \textcopyright 1990

Relations between compositional traits and sensory qualities of french dry-cured ham

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