476 research outputs found
The revenues of local governments in the statistical register for public administrations: inequality decomposition by sources
During the last decade, the Italian national institute of statistics (Istat) has been
engaged in a modernization program involving the revision of the statistical
production model. The main goal behind this program is the use of statistical
registers integrated into a single logical environment, the Italian Integrated System
of Statistical Registers (ISSR), for supporting the consistency of statistical
production processes and improving the quality of information for users. One object
of the ISSR is the satellite statistical REgister for Public Administrations (REPA)
that contains information on structural and economic variables on a subset of the
Italian PA. The public institutions are different from each other in structures, dimensions,
and scopes. In the present paper, these differences are analysed by looking at their
revenues. For this aim, the inequality in the revenues, measured with the Gini index,
is decomposed “by sources”
Spectral signature of short attosecond pulse trains
We report experimental measurements of high-order harmonic spectra generated
in Ar using a carrier-envelope-offset (CEO) stabilized 12 fs, 800nm laser field
and a fraction (less than 10%) of its second harmonic. Additional spectral
peaks are observed between the harmonic peaks, which are due to interferences
between multiple pulses in the train. The position of these peaks varies with
the CEO and their number is directly related to the number of pulses in the
train. An analytical model, as well as numerical simulations, support our
interpretation
Efficient GW calculations via the interpolation of the screened interaction in momentum and frequency space: The case of graphene
The calculation of the GW self-energy may be a computational challenge due to
the double convolution integrals over frequency and transferred momentum. In
this work, we combine the recently developed multipole approximation (MPA) with
the W-av method. MPA accurately approximates full-frequency response functions
using a small number of poles, while W-av improves the convergence with respect
to the Brillouin zone (BZ) sampling in 2D materials. The combination of these
techniques is applied to obtain an accurate G0W0 QP band structure of graphene.
The screened interaction of graphene shows a complex low-energy frequency
dependence, that is poorly described with plasmon pole approximations (PPA),
and a sharp q dependence of the dynamical dielectric function over momentum
transfer, making standard BZ integration techniques inefficient. Within the
present development, we compare the calculated QP band structure of graphene
finding an excellent agreement with angle resolved photoemission spectroscopy
(ARPES) measurements
Mid Infrared Photometry of Mass-Losing AGB Stars
We present ground-based mid-infrared imaging for 27 M-, S- and C-type
Asymptotic Giant Branch (AGB) stars. The data are compared with those of the
database available thanks to the IRAS, ISO, MSX and 2MASS catalogues. Our goal
is to establish relations between the IR colors, the effective temperature
, the luminosity and the mass loss rate , for improving
the effectiveness of AGB modelling. Bolometric (absolute) magnitudes are
obtained through distance compilations, and by applying previously-derived
bolometric corrections; the variability is also studied, using data accumulated
since the IRAS epoch. The main results are: i) Values of and for C
stars fit relations previously established by us, with Miras being on average
more evolved and mass losing than Semiregulars. ii) Moderate IR excesses (as
compared to evolutionary tracks) are found for S and M stars in our sample:
they are confirmed to originate from the dusty circumstellar environment. iii)
A larger reddening characterizes C-rich Miras and post-AGBs. In this case, part
of the excess is due to AGB models overestimating for C-stars, as a
consequence of the lack of suitable molecular opacities. This has a large
effect on the colors of C-rich sources and sometimes disentangling the
photospheric and circumstellar contributions is difficult; better model
atmospheres should be used in stellar evolutionary codes for C stars. iv) The
presence of a long-term variability at mid-IR wavelengths seems to be limited
to sources with maximum emission in the 8 -- 20 m region, usually Mira
variables (1/3 of our sample). Most Semiregular and post-AGB stars studied here
remained remarkably constant in mid-IR over the last twenty years.Comment: Accepted for publication in the Astronomical Journal - 35 pages (in
preprint), 9 figures, 5 table
On the magnetic structure and wind parameter profiles of Alfven wave driven winds in late-type supergiant stars
Cool stars at giant and supergiant evolutionary phases present low velocity
and high density winds, responsible for the observed high mass-loss rates.
Although presenting high luminosities, radiation pressure on dust particles is
not sufficient to explain the wind acceleration process. Among the possible
solutions to this still unsolved problem, Alfven waves are, probably, the most
interesting for their high efficiency in transfering energy and momentum to the
wind. Typically, models of Alfven wave driven winds result in high velocity
winds if they are not highly damped. In this work we determine
self-consistently the magnetic field geometry and solve the momentum, energy
and mass conservation equations, to demonstrate that even a low damped Alfven
wave flux is able to reproduce the low velocity wind. We show that the magnetic
fluxtubes expand with a super-radial factor S>30 near the stellar surface,
larger than that used in previous semi-empirical models. The rapid expansion
results in a strong spatial dilution of the wave flux. We obtained the wind
parameter profiles for a typical supergiant star of 16 M_sun. The wind is
accelerated in a narrow region, coincident with the region of high divergence
of the magnetic field lines, up to 100 km/s. For the temperature, we obtained a
slight decrease near the surface for low damped waves, because the wave heating
mechanism is less effective than the radiative losses. The peak temperature
occurs at 1.5 r_0 reaching 6000 K. Propagating outwards, the wind cools down
mainly due to adiabatic expansion.Comment: to appear in the MNRA
Structural Performance of Reinforced Concrete Flat Plate Buildings Subjected to Fire
El siguiente artĂculo se propone estudiar la poesĂa de Luis Hernández a partir de los problemas que surgen al intentar estudiar su obra reunida. Antes que ser valorada como una poesĂa “inacabada”, la deliberada asistematicidad de su poĂ©tica debe ser entendida como el resultado de un calculado y consciente ejercicio artĂstico, cuyas fuentes filosĂłficas tradicionalmente han pugnado por una ontologĂa del movimiento frente a una metafĂsica de la permanencia. Bajo esta perspectiva, la obra de Hernández se revela como un “plano de inmanencia”, desde el cual acontece el sentido de su poesĂa en el quehacer de la escritura.The article aims to study Luis Hernández’ poetry from the point of view of the problems that emerge when trying to analyze his Complete Works. Rather than being assessed as “unfinished”, the deliberate and unsystematic appearance of his poetic, should rather be understood as the result of a calculated and conscious artistic practice that stems from philosophical trends which traditionally have fostered an ontology of movement against a metaphysics of permanence. Under this view, Hernández work shows up as “plane of immanence” from where sense becomes an event for the creative writing process.El segĂĽent article es proposa estudiar la poesia de Luis Hernández a partir dels problemes que sorgeixen al tractar d’estudiar la seva obra reunida. Abans de ser valorada com una poesia “incabada”, la deliberada asistematicitat de la seva poètica deu ser entesa com el resultat d’un calculat i conscient exercici artĂstic, fonts filosòfiques de les quals han pugnat tradicionalment per una ontologia del moviment davant una metafĂsica de la permanència. Sota aquesta perspectiva, l’obra d’HernĂ ndez es revela com un “pla d’inmanència”, des del qual esdevĂ© el sentit de la seva poesia en el afer de l’escriptura
Breast milk butyrate as protective factor against food allergy
Conflicting evidences suggest a role for breast milk as pro-
tective factor against food allergy. The major short chain fatty
acids, butyrate produced by gut microbiota exerts positive effect
on immune system. We aimed to see whether butyrate concen-
tration in human milk is able to prevent food allergy in an animal
model of cow milk allergy.
Mature breast milk butyrate concentration from 40 healthy
women (aged 21–42 yrs) was assessed by gas chromatography. 4-
Week-old female C3H/HeOuJ mice were sensitized by oral route
with -lactoglobulin (BLG, 20 mg) plus cholera toxin (CT, 10 g)
as an adjuvant in the presence or absence of butyrate. Acute aller-
gic skin response,anaphylactic symptom score, body temperature,
intestinal permeability, anti-BLG IgE, IL-4 and IL-10 production
were assessed soon after oral challenge. Mean butyrate concen-
tration in breast milk was 0.75 mM (SD ± 0.15). Based on this
concentration a daily dose of 30 mg/kg body weight was calculated.
The same butyrate concentration was able to significantly prevent
acute allergic skin response, anaphylactic symptom score, body
temperature decrease, intestinal permeability increase, anti-BLG
IgE, IL-4 and IL-10 production in CMA animal model (p < .05).
Our data suggest a pivotal role for butyrate as an effective human
milk component in food allergy prevention
The new low-toxic histone deacetylase inhibitor S-(2) induces apoptosis in various acute myeloid leukemia cells
Histone deacetylase inhibitors (HDACi) induce tumour cell cycle arrest and/or apoptosis, and some of them are currently used in cancer therapy. Recently, we described a series of powerful HDACi characterized by a 1,4-benzodiazepine (BDZ) ring hybridized with a linear alkyl chain bearing a hydroxamate function as Zn(++)-chelating group. Here, we explored the anti-leukaemic properties of three novel hybrids, namely the chiral compounds (S)-2 and (R)-2, and their non-chiral analogue 4, which were first comparatively tested in promyelocytic NB4 cells. (S)-2 and partially 4– but not (R)-2 – caused G0/G1 cell-cycle arrest by up-regulating cyclin G2 and p21 expression and down-regulating cyclin D2 expression, and also apoptosis as assessed by cell morphology and cytofluorimetric assay, histone H2AX phosphorylation and PARP cleavage. Notably, these events were partly prevented by an anti-oxidant. Moreover, novel HDACi prompted p53 and α-tubulin acetylation and, consistently, inhibited HDAC1 and 6 activity. The rank order of potency was (S)-2 > 4 > (R)-2, reflecting that of other biological assays and addressing (S)-2 as the most effective compound capable of triggering apoptosis in various acute myeloid leukaemia (AML) cell lines and blasts from patients with different AML subtypes. Importantly, (S)-2 was safe in mice (up to 150 mg/kg/week) as determined by liver, spleen, kidney and bone marrow histopathology; and displayed negligible affinity for peripheral/central BDZ-receptors. Overall, the BDZ-hydroxamate (S)-2 showed to be a low-toxic HDACi with powerful anti-proliferative and pro-apototic activities towards different cultured and primary AML cells, and therefore of clinical interest to support conventional anti-leukaemic therapy
CSF parvalbumin levels reflect interneuron loss linked with cortical pathology in multiple sclerosis
INTRODUCTION AND METHODS: In order to verify whether parvalbumin (PVALB), a protein specifically expressed by GABAergic interneurons, could be a MS-specific marker of grey matter neurodegeneration, we performed neuropathology/molecular analysis of PVALB expression in motor cortex of 40 post-mortem progressive MS cases, with/without meningeal inflammation, and 10 control cases, in combination with cerebrospinal fluid (CSF) assessment. Analysis of CSF PVALB and neurofilaments (Nf-L) levels combined with physical/cognitive/3TMRI assessment was performed in 110 naïve MS patients and in 32 controls at time of diagnosis. RESULTS: PVALB gene expression was downregulated in MS (fold change = 3.7 ± 1.2, P < 0.001 compared to controls) reflecting the significant reduction of PVALB+ cell density in cortical lesions, to a greater extent in MS patients with high meningeal inflammation (51.8, P < 0.001). Likewise, post-mortem CSF-PVALB levels were higher in MS compared to controls (fold change = 196 ± 36, P < 0.001) and correlated with decreased PVALB+ cell density (r = -0.64, P < 0.001) and increased MHC-II+ microglia density (r = 0.74, P < 0.01), as well as with early age of onset (r = -0.69, P < 0.05), shorter time to wheelchair (r = -0.49, P < 0.05) and early age of death (r = -0.65, P < 0.01). Increased CSF-PVALB levels were detected in MS patients at diagnosis compared to controls (P = 0.002). Significant correlation was found between CSF-PVALB levels and cortical lesion number on MRI (R = 0.28, P = 0.006) and global cortical thickness (R = -0.46, P < 0.001), better than Nf-L levels. CSF-PVALB levels increased in MS patients with severe cognitive impairment (mean ± SEM:25.2 ± 7.5 ng/mL) compared to both cognitively normal (10.9 ± 2.4, P = 0.049) and mild cognitive impaired (10.1 ± 2.9, P = 0.024) patients. CONCLUSIONS: CSF-PVALB levels reflect loss of cortical interneurons in MS patients with more severe disease course and might represent an early, new MS-specific biomarker of cortical neurodegeneration, atrophy, and cognitive decline
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