114 research outputs found
Église et société au Moyen-Âge
On ne peut comprendre le Moyen Âge sans comprendre le rôle de l’Église.De la chute de l’empire romain d’occident et la conversion des royaumes barbares aux débuts de la Renaissance, l’Europe et la chrétienté se confondent.Cet ouvrage permet de comprendre le rôle de l’Église dans l’évolution de la société médiévale. Un rôle culturel et politique mais aussi économique et juridique. C’est l’Église qui en grande partie forge cette société qui n’est pas sans réagir, parfois violement. La fin du Moyen âge marque un retour des crises internes qui annoncent la réforme.POINTS FORTS- L’ouvrage est parfaitement à jour des recherches les plus récentes.- Les relations entre l’Église et la société sont analysées de façon exhaustives et synthétiquesSOMMAIREPartie 1 : Essor et diversité du christianisme en occident (vers 400-vers 750)1. Héritage de l\u27antiquité tardive2. Les églises des royaumes occidentaux3. Le monde des moines : unité ou diversité ?4. L\u27encadrement des fidèlesPartie 2 : Une église universelle et homogène : le rêve impossible ?(vers 750-vers 1050)1. L\u27ordre carolingien et son rayonnement2. Les conflits d\u27intérêts au sein de l\u27église carolingienne3. Rénovation imperii et expansion de la chrétienté (vers 920-vers 1020)4. Vers une institutionnaliasation de l\u27ecclesia (vers 1020-vers 1050)Partie 3 : Apogée de la papauté et christianisation de la société (vers 1050-vers 1274)1. L\u27affirmation de la papauté (vers 1050 – vers 1190)2. Vigueur de l\u27institution et vitalité de la vie religieuse au XIIe siècle3. Le "beau XIIIe siècle" de l\u27Eglise : réalités et limites4. La christianisation de la société : résistances et contestationsPartie 4 : Le temps des crises et des réformes (vers 1274-vers 1517)5. De l\u27apogée de la papauté à la première crise des institutions6. Schismes, conciles et essor des églises nationales (1378- début XVIe s.)7. La réforme du clergé : succès et limites8. Réforme et vie religieuse des laïcsLES AUTEURS- Anne-Marie Helvétius est professeur d’histoire médiévale à l’université Paris-VIII-Vincennes-Saint-Denis.- Jean-Michel Matz est professeur d’histoire médiévale à l’université d’Anger.PUBLIC CIBLE- Étudiants en histoire en Licence et en Master
Spiral inflow feeding the nuclear starburst in M83, observed in H-alpha emission with the GHAFAS Fabry-Perot interferometer
We present observations of the nearby barred starburst galaxy, M83 (NGC5236),
with the new Fabry-Perot interferometer GHAFAS mounted on the 4.2 meter William
Herschel Telescope on La Palma. The unprecedented high resolution observations,
of 16 pc/FWHM, of the H-alpha-emitting gas cover the central two kpc of the
galaxy. The velocity field displays the dominant disk rotation with signatures
of gas inflow from kpc scales down to the nuclear regions. At the inner Inner
Lindblad Resonance radius of the main bar and centerd at the dynamical center
of the main galaxy disk, a nuclear rapidly
rotating disk with scale length of pc has formed. The nuclear
starburst is found in the vicinity as well as inside this nuclear disk, and our
observations confirm that gas spirals in from the outer parts to feed the
nuclear starburst, giving rise to several star formation events at different
epochs, within the central 100 pc radius of M83.Comment: Accepted for publication in ApJ Letters. High-resolution version can
be found at http://www.astro.su.se/~kambiz/DOC/paper-M83.pd
GHASP : An Halpha kinematic survey of spiral and irregular galaxies - VI. New Halpha data cubes for 108 galaxies
We present the Fabry-Perot observations obtained for a new set of 108
galaxies that completes the GHASP survey (Gassendi HAlpha survey of SPirals).
The GHASP survey consists of 3D Ha data cubes for 203 spiral and irregular
galaxies, covering a large range in morphological types and absolute
magnitudes, for kinematics analysis. The GHASP sample is by now the largest
sample of Fabry-Perot data ever published. We have derived Ha data cubes from
which are computed Ha maps, radial velocity fields as well as residual velocity
fields, position-velocity diagrams, rotation curves and the kinematical
parameters for almost all galaxies. Original improvements in the determination
of the kinematical parameters, rotation curves and their uncertainties have
been implemented in the reduction procedure. This new method is based on the
whole 2D velocity field and on the power spectrum of the residual velocity
fieldrather than the classical method using successive crowns in the velocity
field. Among the results, we point out that morphological position angles have
systematically higher uncertainties than kinematical ones, especially for
galaxies with low inclination. Morphological inclination of galaxies having no
robust determination of their morphological position angle cannot be
constrained correctly. Galaxies with high inclination show a better agreement
between their kinematical inclination and their morphological inclination
computed assuming a thin disk. The consistency of the velocity amplitude of our
rotation curves have been checked using the Tully-Fisher relationship. Our data
are in good agreement with previous determinations found in the literature.
Nevertheless, galaxies with low inclination have statistically higher
velocities than expected and fast rotators are less luminous than expected.Comment: accepted in MNRAS for publication, 60 pages, 25 figures, usues
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A kinematic study of the irregular dwarf galaxy NGC 2366 using HI and Halpha observations
Abridged. Context. The metal content of dwarf galaxies and the metal
enrichment of the intergalactic medium both suggest that mass loss from
galaxies is a significant factor for the chemical evolution history of
galaxies, in particular of dwarf galaxies. However, no clear evidence of a
blow-away in local dwarf galaxies has been found so far.
Aims. We therefore performed a detailed kinematic analysis of the neutral and
ionised gas in the nearby star-forming irregular dwarf galaxy NGC 2366 in order
to make predictions about the fate of the gas and to get a more complete
picture of this galaxy.
Methods. A deep Halpha image and Fabry-Perot interferometric data of NGC 2366
were obtained. They were complemented by HI synthesis data from the THINGS
survey. We searched for line-splitting both in Halpha and HI by performing a
Gaussian decomposition. To get an idea whether the expansion velocities are
high enough for a gas blow-away, we used the pseudo-isothermal halo model,
which gives us realistic values for the escape velocities of NGC 2366. The good
data quality also allowed us to discuss some peculiarities of the morphology
and the dynamics in NGC 2366.
Results. A large red-shifted outflow north west of the giant extragalactic
HII region with an expansion velocity of up to 50 km/s is found in Halpha, but
not in HI. Additionally, a blue-shifted component north of the giant
extragalactic HII region was detected both in Halpha and HI with an expansion
velocity of up to 30 km/s. A comparison with the escape velocities of NGC 2366
reveals that the gas does not have enough kinetic energy to leave the
gravitational potential.Comment: 15 pages, 14 figures, accepted for publication by A&
Imaging of Dysfunctional Elastogenesis in Atherosclerosis Using an Improved Gadolinium-Based Tetrameric MRI Probe Targeted to Tropoelastin
Dysfunctional elastin turnover plays a major role in the progression of atherosclerotic plaques. Failure of tropoelastin cross-linking into mature elastin leads to the accumulation of tropoelastin within the growing plaque, increasing its instability. Here we present Gd4-TESMA, an MRI contrast agent specifically designed for molecular imaging of tropoelastin within plaques. Gd4-TESMA is a tetrameric probe composed of a tropoelastin-binding peptide (the VVGS-peptide) conjugated with four Gd(III)-DOTA-monoamide chelates. It shows a relaxivity per molecule of 34.0 ± 0.8 mM-1 s-1 (20 MHz, 298 K, pH 7.2), a good binding affinity to tropoelastin (KD = 41 ± 12 μM), and a serum half-life longer than 2 h. Gd4-TESMA accumulates specifically in atherosclerotic plaques in the ApoE-/- murine model of plaque progression, with 2 h persistence of contrast enhancement. As compared to the monomeric counterpart (Gd-TESMA), the tetrameric Gd4-TESMA probe shows a clear advantage regarding both sensitivity and imaging time window, allowing for a better characterization of atherosclerotic plaques
SUBARU prime focus spectrograph: integration, testing and performance for the first spectrograph
The Prime Focus Spectrograph (PFS) of the Subaru Measurement of Images and
Redshifts (SuMIRe) project for Subaru telescope consists in four identical
spectrographs fed by 600 fibers each. Each spectrograph is composed by an
optical entrance unit that creates a collimated beam and distributes the light
to three channels, two visibles and one near infrared. This paper presents the
on-going effort for the tests & integration process for the first spectrograph
channel: we have developed a detailed Assembly Integration and Test (AIT) plan,
as well as the methods, detailed processes and I&T tools. We describe the tools
we designed to assemble the parts and to test the performance of the
spectrograph. We also report on the thermal acceptance tests we performed on
the first visible camera unit. We also report on and discuss the technical
difficulties that did appear during this integration phase. Finally, we detail
the important logistic process that is require to transport the components from
other country to Marseille
First light of VLT/HiRISE: High-resolution spectroscopy of young giant exoplanets
A major endeavor of this decade is the direct characterization of young giant exoplanets at high spectral resolution to determine the composition of their atmosphere and infer their formation processes and evolution. Such a goal represents a major challenge owing to their small angular separation and luminosity contrast with respect to their parent stars. Instead of designing and implementing completely new facilities, it has been proposed to leverage the capabilities of existing instruments that offer either high-contrast imaging or high-dispersion spectroscopy by coupling them using optical fibers. In this work, we present the implementation and first on-sky results of the High-Resolution Imaging and Spectroscopy of Exoplanets (HiRISE) instrument at the Very Large Telescope (VLT), which combines the exoplanet imager SPHERE with the recently upgraded high-resolution spectrograph CRIRES using single-mode fibers. The goal of HiRISE is to enable the characterization of known companions in the H band at a spectral resolution on the order of R = λ/∆λ = 100 000 in a few hours of observing time. We present the main design choices and the technical implementation of the system, which is constituted of three major parts: the fiber injection module inside of SPHERE, the fiber bundle around the telescope, and the fiber extraction module at the entrance of CRIRES. We also detail the specific calibrations required for HiRISE and the operations of the instrument for science observations. Finally, we detail the performance of the system in terms of astrometry, temporal stability, optical aberrations, and transmission, for which we report a peak value of ~3.9% based on sky measurements in median observing conditions. Finally, we report on the first astrophysical detection of HiRISE to illustrate its potential
First light of VLT/HiRISE: High-resolution spectroscopy of young giant exoplanets
A major endeavor of this decade is the direct characterization of young giant
exoplanets at high spectral resolution to determine the composition of their
atmosphere and infer their formation processes and evolution. Such a goal
represents a major challenge owing to their small angular separation and
luminosity contrast with respect to their parent stars. Instead of designing
and implementing completely new facilities, it has been proposed to leverage
the capabilities of existing instruments that offer either high contrast
imaging or high dispersion spectroscopy, by coupling them using optical fibers.
In this work we present the implementation and first on-sky results of the
HiRISE instrument at the very large telescope (VLT), which combines the
exoplanet imager SPHERE with the recently upgraded high resolution spectrograph
CRIRES using single-mode fibers. The goal of HiRISE is to enable the
characterization of known companions in the band, at a spectral resolution
of the order of , in a few hours of
observing time. We present the main design choices and the technical
implementation of the system, which is constituted of three major parts: the
fiber injection module inside of SPHERE, the fiber bundle around the telescope,
and the fiber extraction module at the entrance of CRIRES. We also detail the
specific calibrations required for HiRISE and the operations of the instrument
for science observations. Finally, we detail the performance of the system in
terms of astrometry, temporal stability, optical aberrations, and transmission,
for which we report a peak value of 3.9% based on sky measurements in
median observing conditions. Finally, we report on the first astrophysical
detection of HiRISE to illustrate its potential.Comment: 17 pages, 15 figures, 3 tables. Submitted to A&A on 19 September 202
Emission of volatile halogenated compounds, speciation and localization of bromine and iodine in the brown algal genome model Ectocarpus siliculosus
This study explores key features of bromine and iodine metabolism in the filamentous brown alga and genomics model Ectocarpus siliculosus. Both elements are accumulated in Ectocarpus, albeit at much lower concentration factors (2-3 orders of magnitude for iodine, and < 1 order of magnitude for bromine) than e.g. in the kelp Laminaria digitata. Iodide competitively reduces the accumulation of bromide. Both iodide and bromide are accumulated in the cell wall (apoplast) of Ectocarpus, with minor amounts of bromine also detectable in the cytosol. Ectocarpus emits a range of volatile halogenated compounds, the most prominent of which by far is methyl iodide. Interestingly, biosynthesis of this compound cannot be accounted for by vanadium haloperoxidase since the latter have not been found to catalyze direct halogenation of an unactivated methyl group or hydrocarbon so a methyl halide transferase-type production mechanism is proposed
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