Introduction : l’évolution européenne des dépôts et de leurs ateliers

Cette contribution introductive présente un riche ensemble iconographique portant sur l’évolution architecturale des dépôts et ateliers en Europe, au cours du XXe siècle essentiellement. Le modèle de la rotonde s’opposa ainsi jusqu’au milieu du siècle environ aux installations rectangulaires à voies parallèles qui sont devenues la norme aujourd’hui, après les adaptations successives des installations aux trois grands modes de traction et enfin à l’avènement de la grande vitesse et de l’informatisation des infrastructures.This introductory paper presents a rich iconographic set on the architectural evolution of depots and workshops in Europe, essentially during the XXth Century. The model of the rotunda is thus opposed until the mid-century to rectangular parallel pathways installations. The latter have become the standard today after the successive adaptations of facilities to three major modes of traction and at last the advent of high-speed and computerization of infrastructure

Les dépôts de matériel moteur ferroviaire de la région Tourangelle

La région tourangelle et la ville de Tours en particulier furent desservies de très bonne heure par le chemin de fer, puisque « l’embarcadère » s’ouvrit au service des voyageurs le 2 avril 1846, trois ans seulement après le Paris-Orléans. La multiplicité des exploitants ferroviaires initiaux entraîna au XIXe siècle un grand développement des installations du chemin de fer, avec pour corollaire une population cheminote importante puisqu’elle s’éleva jusqu’à 6 000 employés, dans quatre dépôts totalisant presque 100 machines dans la première moitié du XXe siècle. La SNCF, héritière des compagnies avec environ 2 000 emplois, représente encore actuellement le premier employeur de la région. Son activité nécessite des installations pour les voyageurs (gares de Tours et Saint-Pierre-des-Corps), une gare de triage pour les marchandises, un dépôt pour les locomotives et automotrices et un grand atelier de maintenance. Cet article retrace l’histoire, entre 1850 et 1960 principalement, de ce très important nœud ferroviaire à travers ses nombreuses implantations (jusqu’à cinq sites, dont certains simultanément). Dans le domaine plus spécifique de la traction, hors les grands ateliers généraux, Tours-Saint-Pierre-des-Corps a compté jusqu’à sept dépôts d’engins moteurs à voie normale, auxquels il faut ajouter pour la région tourangelle les deux dépôts à voie métrique des CFD et les deux dépôts de tramways, l’un à vapeur à Vouvray, l’autre électrique à Tours. De nos jours ne subsiste plus que le dépôt SNCF de Saint-Pierre-des-Corps, ou « Tours-Saint-Pierre ».The region of Touraine and the city of Tours in particular were connected very early by railways, since the "embarcadère" opened to the service of passengers on 2 April 1846, only three years after the Paris-Orleans. In the 19th Century, the multiplicity of initial rail operators resulted in a great development of railway facilities with corollary railwaymen population, which raised up to 6,000 railwaymen and four depots (totallizing less than 100 machines) in the first half of the 20th Century. The SNCF, heiress of companies with a staff of approximately 2000, is currently the largest employer of the Touraine region. Its activity requires facilities for passengers (railway stations of Tours and Saint-Pierre-des-Corps), a railway yard for goods, a depot for locomotives and railcars, and a large maintenance workshop. This article traces the history, between 1850 and 1960 primarily, of this very important railway centre through its many settlements (up to five sites, some of them simultaneously). In the more specific field of traction, not to speak of great general workshops, Tours-Saint-Pierre-des-Corps has counted up to seven depots for propelling engines in normal track. To that figure must be added, for the region, two metric track depots for the CFD and two trams depots (steam in Vouvray, electrical in Tours). Nowadays only remains the SNCF depot of Saint-Pierre-des-Corp, or "Tours-Saint-Pierre"

Effet d’un programme d’activité physique intermittent de haute intensité sur la perte de masse grasse abdominale chez la femme DT2 ménopausée

Contexte : A la ménopause, la diminution des taux d’estrogènes favorise un dépôt de masse grasse (MG) abdominal (sous-cutané et viscéral). La MG viscérale est corrélée aux maladies cardio-vasculaires (MCV). Ce risque est accentué chez les sujets présentant un diabète de type 2 (DT2).Objectif : Comparer deux modalités d’entraînement, continu de moyenne intensité (SSE) vs. intermittent de haute intensité (HIIE), sur la perte de MG abdominale (dont viscérale) chez des femmes DT2 ménopausées.Matériels et méthode : Seize femmes DT2 ménopausées (69±1ans; IMC : 31±1 kg/m²) ont été réparties aléatoirement en deux groupes. Pendant quatre mois, deux fois par semaine, 8 d’entre elles ont réalisé un entraînement SSE (40 min de pédalage à 50% de la FCmax de réserve), et 8 ont réalisé un entraînement HIIE (8s de sprint suivies de 12s de récupération active, pendant 20 min). Pré (T0) et post entraînement (T4), la composition corporelle et la MG abdominale totale ont été mesurées par DXA (Dual Energy X-ray Absorptiometry). La MG viscérale a été estimée à partir de la méthode de Martin et Jensen1. A T0 et T4, les apports énergétiques et le niveau d’activité physique ont été déterminés (questionnaires et accéléromètrie validée2 intégrée sur smartphone).Résultats : Après 16 semaines d’intervention, sans modification des apports énergétiques et du niveau d’activité physique total, une perte de MG totale et un gain de masse maigre est observé (effet temps, p<0.05). La diminution de MG abdominale est supérieure dans le groupe HIIE (0.32% ± 2.07 vs 8.32 % ± 2.19, p<0.05) et la perte de MG viscérale n’est observée que dans le groupe HIIE (p<0.05).Conclusion : L’entraînement de type HIIE apparait comme un programme alternatif intéressant chez la femme DT2 ménopausée en diminuant significativement la MG abdominale totale et viscérale

The role of herbivorous insects and pathogens in the regeneration dynamics of Guazuma ulmifolia in Panama

A significant proportion of the mortality of rainforest trees occurs during early life stages (seeds and seedlings), but mortality agents are often elusive. Our study investigated the role of herbivorous insects and pathogens in the early regeneration dynamics of Guazuma ulmifolia (Malvaceae), an important tree species in agroforestry in Central America. We reared pre-dispersal insect seed predators from G. ulmifolia seeds in Panama. We also carried out an experiment, controlling insects and pathogens using insecticide and/or fungicide treatments, as well as seed density, and compared survivorship of G. ulmifolia seeds and seedlings among treatments and relative to untreated control plots. We observed (1) high pre-dispersal attack (92%) of the fruits of G. ulmifolia, mostly by anobiine and bruchine beetles; (2) negligible post-dispersal attack of isolated seeds by insects and pathogens; (3) slow growth and high mortality (> 95%) of seedlings after 14 weeks; (4) low insect damage on seedlings; and (5) a strong positive correlation between seedling mortality and rainfall. We conclude that for G. ulmifolia at our study site the pre-dispersal seed stage is by far the most sensitive stage to insects and that their influence on seedling mortality appears to be slight as compared to that of inclement weather. Thus, the regeneration of this important tree species may depend on effective primary dispersal of seeds by vertebrates (before most of the seed crop is lost to insects), conditioned by suitable conditions in which the seedlings can grow

Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study

The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases.Rudyanto, RD.; Kerkstra, S.; Van Rikxoort, EM.; Fetita, C.; Brillet, P.; Lefevre, C.; Xue, W.... (2014). Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study. Medical Image Analysis. 18(7):1217-1232. doi:10.1016/j.media.2014.07.003S1217123218

Reduction of microglial activity in a model of multiple sclerosis by dipyridamole

BACKGROUND: Despite extensive and persistent activation of microglia in multiple sclerosis (MS), microglia inhibitors have not yet been identified for treatment of the disorder. We sought to identify medications already in clinical use that could inhibit the activation of microglia. On the basis of the reported inhibitory effects of dipyridamole on phosphodiesterase activity that result in the production of various anti-inflammatory outcomes, we selected it for study. Dipyridamole is used clinically for secondary prevention in stroke. In this study, dipyridamole was examined using microglia in culture and in the mouse model of MS, experimental autoimmune encephalomyelitis (EAE). RESULTS: We found that dipyridamole attenuated the elevation of several cytokines and chemokines in human microglia caused by Toll-like receptor stimulation. Morphological characteristics of activated microglia in culture were also normalized by dipyridamole. In mice, dipyridamole decreased the clinical severity of EAE and reduced microglial activity and other histological indices of EAE in the spinal cord. CONCLUSIONS: Dipyridamole is an inhibitor of microglia activation and may have a role in MS and other neurological conditions to attenuate microglial activity

Functional analysis of Casein Kinase 1 in a minimal circadian system

The Earth's rotation has driven the evolution of cellular circadian clocks to facilitate anticipation of the solar cycle. Some evidence for timekeeping mechanism conserved from early unicellular life through to modern organisms was recently identified, but the components of this oscillator are currently unknown. Although very few clock components appear to be shared across higher species, Casein Kinase 1 (CK1) is known to affect timekeeping across metazoans and fungi, but has not previously been implicated in the circadian clock in the plant kingdom. We now show that modulation of CK1 function lengthens circadian rhythms in Ostreococcustauri, a unicellular marine algal species at the base of the green lineage, separated from humans by ~1.5 billion years of evolution. CK1 contributes to timekeeping in a phase-dependent manner, indicating clock-mediated gating of CK1 activity. Label-free proteomic analyses upon overexpression as well as inhibition revealed CK1-responsive phosphorylation events on a set of target proteins, including highly conserved potentially clock-relevant cellular regulator proteins. These results have major implications for our understanding of cellular timekeeping and can inform future studies in any circadian organism

Extension d'une méthode approchée pour le calcul de l'énergie de corrélation électronique aux molécules contenant des atomes de la troisième période

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Semi-empirical calculation of the molecular correlation energy

A simplified method for molecular correlation energy calculations has been recently proposed (ref. 1-2) on the basis of a partition into internal and non-internal contributions. The field of application of the method is discussed, some typical results are commented and recent developments are presented. The formalism of the "atoms-in-molecule" approach adopted for the non-internal correlation energy calculations is analyzed in order to optimize its programming. The extension of the method to molecules containing atoms of the third row is considered and particular emphasis is layed on the choice of semi-empirical atomic data. Finally, preliminar results obtained for the Chlorine atom are presented. © 1984.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Extension of a simplified method for molecular correlation energy calculations to molecules containing third row atoms II. Application to HCl, HCl+, ClO and NCl molecules

A simplified method for molecular correlation energy calculations developed in I is applied to the determination of the potential curves of some diatomic chlorinated molecules HCl(1Σ+), HCl+(2II), ClO(2II) and NCl(X3Σ-, a1Δ, b1Σ+). Dissociation energies, vibrational frequencies and equilibrium internuclear distances are derived from these curves. The ionisation potential (Ip) of HCl, the proton affinity (PA) of Cl, and the term energies of the excited states of the NCl radical are also calculated. It is shown that the results are very sensitive to correlation effects and that the correlated results converge to the corresponding experimental values within 10% for PA, De, Te and ωe, 2% for Re and 0.3% for Ip. This agreement allows us to predict the following lower limits for the dissociation energies of the NCl radical: 2.14, 3.28 and 2.47 eV respectively for the X3Σ-, a1Δ and b1Σ+ states. Results on HF and HF+ are also discussed and compared with those obtained for HCl and HCl+. © 1985 Springer-Verlag.SCOPUS: ar.jinfo:eu-repo/semantics/publishe