4,866 research outputs found
Influence of the halo upon angular distributions for elastic scattering and breakup
The angular distributions for elastic scattering and breakup of halo nuclei
are analysed using a near-side/far-side decomposition within the framework of
the dynamical eikonal approximation. This analysis is performed for 11Be
impinging on Pb at 69 MeV/nucleon. These distributions exhibit very similar
features. In particular they are both near-side dominated, as expected from
Coulomb-dominated reactions. The general shape of these distributions is
sensitive mostly to the projectile-target interactions, but is also affected by
the extension of the halo. This suggests the elastic scattering not to be
affected by a loss of flux towards the breakup channel.Comment: 11 pages, 3 figures, accepted for publication in Phys. Lett.
The CMCC-INGV Global Ocean Data Assimilation System (CIGODAS)
This report summarizes the technical structure and main
characteristics of the CMCCINGV Global Ocean Data Assimilation System (CIGODAS) based on a Reduced Order Optimal Interpolation scheme and a coarse resolution Global Ocean Model for the assimilation of temperature and salinity observations. It is intended to be a reference guide for new users who are interested in setting up and running an experiment using this approach and producing estimates of the timevarying, threedimensional state of the global ocean
Spectral weight redistribution in (LaNiO3)n/(LaMnO3)2 superlattices from optical spectroscopy
We have studied the optical properties of four
(LaNiO)/(LaMnO) superlattices (SL) (=2, 3, 4, 5) on
SrTiO substrates. We have measured the reflectivity at temperatures from 20
K to 400 K, and extracted the optical conductivity through a fitting procedure
based on a Kramers-Kronig consistent Lorentz-Drude model. With increasing
LaNiO thickness, the SLs undergo an insulator-to-metal transition (IMT)
that is accompanied by the transfer of spectral weight from high to low
frequency. The presence of a broad mid-infrared band, however, shows that the
optical conductivity of the (LaNiO)/(LaMnO) SLs is not a linear
combination of the LaMnO and LaNiO conductivities. Our observations
suggest that interfacial charge transfer leads to an IMT due to a change in
valence at the Mn and Ni sites.Comment: Accepted for publication in Phys. Rev. Lett. 5 pages, 5 figure
Complex delay dynamics on railway networks: from universal laws to realistic modelling
Railways are a key infrastructure for any modern country. The reliability and
resilience of this peculiar transportation system may be challenged by
different shocks such as disruptions, strikes and adverse weather conditions.
These events compromise the correct functioning of the system and trigger the
spreading of delays into the railway network on a daily basis. Despite their
importance, a general theoretical understanding of the underlying causes of
these disruptions is still lacking. In this work, we analyse the Italian and
German railway networks by leveraging on the train schedules and actual delay
data retrieved during the year 2015. We use {these} data to infer simple
statistical laws ruling the emergence of localized delays in different areas of
the network and we model the spreading of these delays throughout the network
by exploiting a framework inspired by epidemic spreading models. Our model
offers a fast and easy tool for the preliminary assessment of the
{effectiveness of} traffic handling policies, and of the railway {network}
criticalities.Comment: 32 pages (with appendix), 28 Figures (with appendix), 2 Table
Evidence from multivariate morphometric study of the quercus pubescens complex in southeast Italy
The name Quercus pubescens s.l. encompasses a complex of deciduous oak taxa with mainly southeastEuropean
distribution and a large ecological niche. As the easternmost region of Italy, Apulia is
rather isolated from a geographical and physiographical viewpoint and counts the highest number
of oak species (10). In the taxonomic and phytosociological literature, the occurrence of several
species belonging to the Quercus pubescens collective group is reported for this region. In order to
verify if different sets of morphological characters are associated with different taxa, 24 populations
of Quercus pubescens s.l. located in different ecological-geographical areas of Apulia were sampled.
A total of 367 trees, 4254 leaves and 1120 fruits were collected and morphologically analysed.
Overall, 25 morphological characters of oak leaves and fruits were statistically treated using both
univariate and multivariate analysis. Nested ANOVA showed that leaves collected from a single tree
exhibited a degree of morphological variability higher than that observed when comparing leaves
coming from different trees of the same population and from different trees of different populations
as well. Almost all the morphological characters analysed exhibited a continuous trend of variation
so that none of them can be used as a character to discriminate between populations. Only leaf
and fruit “size” and fruit petiole length emerged as slightly discriminating characters. Our results
suggest that it is unlikely that more than one species belonging to the Quercus pubescens complex
occurs in the Apulia region. Comparison between the Apulian populations and a genetically
pure Q. pubescens population coming from a different area (the Molise region) strengthened the
assumption as to the existence of a single species that can provisionally be classified under the name
of Q. pubescens s.
Phase diagram and optical conductivity of La1.8-xEu0.2SrxCuO4
La1.8-xEu0.2SrxCuO4 (LESCO) is the member of the 214 family which exhibits
the largest intervals among the structural, charge ordering (CO), magnetic, and
superconducting transition temperatures. By using new dc transport measurements
and data in the literature we construct the phase diagram of LESCO between x =
0.8 and 0.20. This phase diagram has been further probed in ac, by measuring
the optical conductivity {\sigma}1({\omega}) of three single crystals with x =
0.11, 0.125, and 0.16 between 10 and 300 K in order to associate the
extra-Drude peaks often observed in the 214 family with a given phase. The
far-infrared peak we detect in underdoped LESCO is the hardest among them,
survives up to room temperature and is associated with charge localization
rather than with ordering. At the CO transition for the commensurate doping x =
0.125 instead the extra-Drude peak hardens and a pseudogap opens in
{\sigma}1({\omega}), approximately as wide as the maximum superconducting gap
of LSCO.Comment: 6 pages, 6 figure
Hyphal growth of phagocytosed fusarium oxysporum causes cell lysis and death of murine macrophages
Peer reviewedPublisher PD
Global ocean re-analyses for climate applications
One of the main objectives of the global ocean modelling activities
at Centro Euro-Mediterraneo per i Cambiamenti Climatici (CMCC)
is the production of global ocean re-analyses over multidecadal
periods to reconstruct the state of the ocean and the large scale cir-
culation over the recent past. The re-analyses are used for climate applications
and for the assessment of the benefits of assimilating
ocean
observations on seasonal and longer predictions.
Here
we present the main characteristics of an optimal interpola-
tion
based assimilation system used to produce a set of global ocean
re-analyses
validated against a set of high quality in situ observa-
tions
and independent data. Differences among the experiments
of
the set are analyzed in terms of improvements in the method
used
to assimilate the data and the quality of observations them-
selves.
For example, the integrated ocean heat content, which can
be
taken as an indicator of climate changes, is examined to detect
possible
sources of uncertainty of its long-term changes. Global and
basin
scale upper ocean heat content exhibits warming trends over
the
last few decades that still depend in a significant way on the
assimilated
observations and the formulation of the background
covariances.
However, all the re-analyses show a global warming
trend
of the oceanic uppermost 700 m over the last five decades
that
falls within the range of the most recent observation-based
estimates.
The largest discrepancies between our estimates and
observational
based ones are confined in the upwelling regions of
the
PacificandAtlanticOceans.Finally,theresultsshow that the climatological
heat and salt transports as a function of latitude also
fall
within the range of the estimates based on observations and
atmospheric
re-analyses
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Effects of the glial modulator palmitoylethanolamide on chronic pain intensity and brain function.
Background: Chronic neuropathic pain (NP) is a complex disease that results from damage or presumed damage to the somatosensory nervous system. Current treatment regimens are often ineffective. The major impediment in developing effective treatments is our limited understanding of the underlying mechanisms. Preclinical evidence suggests that glial changes are crucial for the development of NP and a recent study reported oscillatory activity differences within the ascending pain pathway at frequencies similar to that of cyclic gliotransmission in NP. Furthermore, there is evidence that glial modifying medications may be effective in treating NP. The aim of this Phase I open-label clinical trial is to determine whether glial modifying medication palmitoylethanolamide (PEA) will reduce NP and whether this is associated with reductions in oscillatory activity within the pain pathway. Methods: We investigated whether 6 weeks of PEA treatment would reduce pain and infra-slow oscillatory activity within the ascending trigeminal pathway in 22 individuals (17 females) with chronic orofacial NP. Results: PEA reduced pain in 16 (73%) of the 22 subjects, 11 subjects showed pain reduction of over 20%. Whilst both the responders and non-responders showed reductions in infra-slow oscillatory activity where orofacial nociceptor afferents terminate in the brainstem, only responders displayed reductions in the thalamus. Furthermore, functional connections between the brainstem and thalamus were altered only in responders. Conclusion: PEA is effective at relieving NP. This reduction is coupled to a reduction in resting oscillations along the ascending pain pathway that are likely driven by rhythmic astrocytic gliotransmission
A geobotanical survey on acidophilous grasslands in the Abruzzo, Lazio and Molise National Park (Central Italy)
The acidophilous grasslands of the south-eastern part of the Abruzzo, Lazio and Molise National Park was studied by the phytosociological method and analyzed from a synecological viewpoint with the help of soil analysis. Four clusters of relevés resulted from the numerical classification. Syntaxonomically they were ascribed to the following associations: Poo violaceae-Nardetum strictae, Potentillo rigoanae-Festucetum paniculatae, Nardo strictae-Brachypodietum genuensis and Potentillo rigoanae-Brachypodietum genuensis. Since the original proposal of all the syntaxa identified in the present study were affected by nomenclatural mistakes, they were corrected in accordance with the rules of ICPN. The occurrence of Anthoxanto-Brachypodietum in central Apennines, is excluded since this association falls in syntaxonomical synonymy with Potentillo-Brachypodietum. The synecological analysis proved that the distribution of the different communities identified within the study area to be correlated with topographic, geomorphological and soil factors. Among these latter, the ratio H+/basic cations, pH behave as the most influencing parameters in the distribution of the communities identified
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