1,328 research outputs found
Imbedding estimates and elliptic equations with discontinuous coefficients in unbounded domains
In this paper we deal with the multiplication operator u ∈ W^{k,p} (Ω) → gu ∈ L^q (Ω), with g belonging to a space of Morrey type. We apply our results in order to establish an a-priori bound for the solutions of the Dirichlet problem concerning elliptic equations with discontinuous coefficients
Observing soil moisture temporal variability under fluctuating climatic conditions
International audienceThe paper focuses on the observation of interannual and intra-annual climate variability impact on soil moisture temporal patterns and variation, for an experimental site located in Southern Italy and characterized by a typical Mediterranean climate. Analysed data consist of three years soil water content time series measured during the period 2004?2007, under intermediate (2004/2005), wet (2005/2006) and dry (2006/2007) climatological conditions. Results show that, for the case study, interannual precipitation fluctuation highly impact the annual soil moisture cycle, modifying the number and length of characteristic periods revealed by the cycle patterns. Annual rainfall variation also affects the weight of the wet and dry soil moisture conditions, making the distinction between preferred states more and more evident for increasing precipitation variability. Intra-annual precipitation fluctuation instead mainly impact soil moisture dynamic during the dry period of the year, shifting the position of the modes and the weight of the wet mode and nearly leading the dry mode to disappear for larger mean seasonal rainfall. Reported analyses would be a support and a premise for further modeling implications
Fossil group origins: VIII RXJ075243.6+455653 a transitionary fossil group
It is thought that fossil systems are relics of structure formation in the
primitive Universe. They are galaxy aggregations that have assembled their mass
at high redshift with few or no subsequent accretion. Observationally these
systems are selected by large magnitude gaps between their 1st and 2nd ranked
galaxies. Nevertheless, there is still debate over whether or not this
observational criterium selects dynamically evolved ancient systems. We have
studied the properties of the nearby fossil group RXJ075243.6+455653 in order
to understand the mass assembly of this system. Deep spectroscopic observations
allow us to construct the galaxy luminosity function (LF) of RXJ075243.6+455653
down to M*+ 6. The analysis of the faint-end of the LF in groups and clusters
provides valuable information about the mass assembly of the system. In
addition, we have analyzed the nearby large-scale structure around this group.
We identified 26 group members within r200=0.9 Mpc. The LF of the group shows a
flat faint-end slope ( -1.08 +/- 0.33). This low density of dwarf galaxies is
confirmed by the low value of the dwarf-to-giant ratio (DGR = 0.99 +/- 0.49)
for this system. Both the lack of dwarf galaxies and the low luminosity of the
BGG suggests that RXJ075243.6+455653 still has to accrete mass from its nearby
environment. This mass accretion will be achieved because it is the dominant
structure of a rich environment formed by several groups of galaxies (15)
within 7 Mpc from the group center and with +/- 1000$ km/s. RXJ075243.6+455653
is a group of galaxies that has not yet completed the process of its mass
assembly. This new mass accretion will change the fossil state of the group.
This group is an example of a galaxy aggregation selected by a large magnitude
gap but still in the process of the accretion of its mass (Abridged).Comment: 9 pages, 9 figures, accepted in A&
The planetary nebula population in the halo of M87
We investigate the diffuse light in the outer regions of the nearby
elliptical galaxy M87 in the Virgo cluster, using planetary nebulas (PNs) as
tracers. The surveyed areas (0.43 squared degrees) cover M87 up to a radial
distance of 150 kpc, in the ransition region between galaxy halo and
intracluster light (ICL). All PNs are identified through the on-off band
technique using automatic selection criteria based on the distribution of the
detected sources in the colour-magnitude diagram and the properties of their
point-spread function. We extract a catalogue of 688 objects down to
m_5007=28.4, with an estimated residual contamination from foreground stars and
background Lyalpha galaxies, which amounts to ~35% of the sample. This is one
of the largest extragalactic PN samples in number of candidates, magnitude
depth, and radial extent, which allows us to carry out an unprecedented
photometric study of the PN population in the outer regions of M87. We find
that the logarithmic density profile of the PN distribution is shallower than
the surface brightness profile at large radii. This behaviour is consistent
with the superposition of two components associated with the halo of M87 and
with the ICL, which have different luminosity specific PN numbers, the ICL
contributing three times more PNs per unit light. Because of the depth of this
survey we are also able to study the shape of the PN luminosity function (PNLF)
in the outer regions of M87. We find a slope for the PNLF that is steeper at
fainter magnitudes than the standard analytical PNLF formula and adopt a
generalised model that treats the slope as a free parameter. Comparing the PNLF
of M87 and the M31 bulge, both normalised by the sampled luminosity, the M87
PNLF contains fewer bright PNs and has a steeper slope towards fainter
magnitudes.Comment: 16 pages, 13 figures, 5 tables, accepted for publication in A&
THE REPRESENTATION OF MALE AND FEMALE GENDER ROLE DEVELOPMENT IN CHILDREN’S DRAWINGS: AN EXAMINATION OF 20 YEARS OF CHANGES IN ITALIAN CULTURE AND SOCIETY
Editorial: Towards 2030: Sustainable Development Goal 16: Peace, justice, and strong institutions. An educational perspective
Alexithymia and Self Differentiation: The Role of Fear of Intimacy and Insecure Adult Attachment
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