2,484 research outputs found
IL-1 regulates the IL-23 response to wheat gliadin, the etiologic agent of Celiac Disease
Celiac disease (CD) is an autoimmune disease prevalent in ~1% of the general population. CD is unique because both the major genetic (Human Leukocyte Antigen-DQ2/DQ8 alleles) and etiologic factors (dietary glutens) for susceptibility are known. While these alleles are responsible for the inappropriate T cell response that characterizes CD, they are not sufficient since most HLA-DQ2+/DQ8+ individuals exposed to glutens never develop disease. The reasons for this have not been explained; however our novel findings strongly advocate a role for interleukin-23 (IL-23) in the immunopathogenesis of CD. We demonstrate that wheat gliadin stimulates monocytes to produce significantly higher amounts of inflammatory cytokines IL-1b, IL-23, and tumor necrosis factor-a (TNFa) in CD patients compared to HLA-DQ2+ healthy individuals. Furthermore, we determine that IL-1 signalling is obligatory for production of IL-23, since IL-1b triggers IL-23 secretion in a dose-dependent manner and IL-1 receptor antagonist (IL-1ra) blocks IL-23 responses to gliadin. Our results suggest that gliadin activation of monocytes and the subsequent robust secretion of IL-1b and IL-23 initiate the immune response cascade that is manifest as CD, and reveal for the first time that the IL-1 system regulates production of IL-23. The discovery of IL-23 has highlighted the critical role of the innate immune response in autoimmunity and other inflammatory conditions. We anticipate that our novel findings will lead to the discovery of therapeutic targets for this disease and other inflammatory diseases mediated by IL-23
Order and Creep in Flux Lattices and CDWs Pinned by Planar Defects
The influence of randomly distributed point impurities \emph{and} planar
defects on the order and transport in type-II superconductors and related
systems is considered theoretically. For planar defects of identical
orientation the flux line lattice exhibits a new glassy phase dominated by the
planar defects with a finite compressibility, a transverse Meissner effect,
large sample to sample fuctuations of the susceptibility and an exponential
decay of translational long range order. The flux creep resistivity for
currents parallel to the defects is .
Strong disorder enforces an array of dislocations to relax shear strain
Effect of water nanoconfinement on the dynamic properties of paramagnetic colloidal complexes
The anomalous behavior of confined water at the nanoscale has remarkable implications in a number of nanotechnological applications. In this work, we analyze the effect of water self-diffusion on the dynamic properties of a solvated gadolinium-based paramagnetic complex, typically used for contrast enhancement in magnetic resonance imaging. In particular, we examine the effect of silica-based nanostructures on water behavior in the proximity of the paramagnetic complex via atomistic simulations, and interpret the resulting tumbling dynamics in the light of the local solvent modification based on the Lipari-Szabo formalism and of the fractional Stokes-Einstein relation. It is found that the local water confinement induces an increased "stiffness" on the outer sphere of the paramagnetic complex, which eventually reduces its tumbling properties. These model predictions are found to explain well the relaxivity enhancement observed experimentally by confining paramagnetic complexes into porous nanoconstructs, and thus offer mechanistic guidelines to design improved contrast agents for imaging applications
Nano-metering of Solvated Biomolecules Or Nanoparticles from Water Self-Diffusivity in Bio-inspired Nanopores
Taking inspiration from the structure of diatom algae frustules and motivated by the need for new detecting strategies for emerging nanopollutants in water, we analyze the potential of nanoporous silica tablets as metering devices for the concentration of biomolecules or nanoparticles in water. The concept relies on the different diffusion behavior that water molecules exhibit in bulk and nanoconfined conditions, e.g., in nanopores. In this latter situation, the self-diffusion coefficient of water reduces according to the geometry and surface properties of the pore and to the concentration of suspended biomolecules or nanoparticles in the pore, as extensively demonstrated in a previous study. Thus, for a given pore-liquid system, the self-diffusivity of water in nanopores filled with biomolecules or nanoparticles provides an indirect measure of their concentration. Using molecular dynamics and previous results from the literature, we demonstrate the correlation between the self-diffusion coefficient of water in silica nanopores and the concentration of proteins or nanoparticles contained therein. Finally, we estimate the time required for the nanoparticles to fill the nanopores, in order to assess the practical feasibility of the overall nano-metering protocol. Results show that the proposed approach may represent an alternative method for assessing the concentration of some classes of nanopollutants or biomolecules in water
Short-Term Orchestral Music Training Modulates Hyperactivity and Inhibitory Control in School-Age Children: A Longitudinal Behavioural Study
Survey studies have shown that participating in music groups produces several benefits,
such as discipline, cooperation and responsibility. Accordingly, recent longitudinal
studies showed that orchestral music training has a positive impact on inhibitory control
in school-age children. However, most of these studies examined long periods of training
not always feasible for all families and institutions and focused on children’s measures
ignoring the viewpoint of the teachers. Considering the crucial role of inhibitory control on
hyperactivity, inattention and impulsivity, we wanted to explore if short orchestral music
training would promote a reduction of these impulsive behaviors in children. This study
involved 113 Italian children from 8 to 10 years of age. 55 of them attended 3 months of
orchestral music training. The training included a 2-hour lesson per week at school and
a final concert. The 58 children in the control group did not have any orchestral music
training. All children were administered tests and questionnaires measuring inhibitory
control and hyperactivity near the beginning and end of the 3-month training period.
We also collected information regarding the levels of hyperactivity of the children as
perceived by the teachers at both time points. Children in the music group showed
a significant improvement in inhibitory control. Moreover, in the second measurement
the control group showed an increase in self-reported hyperactivity that was not found
in the group undergoing the music training program. This change was not noticed by
the teachers, implying a discrepancy between self-reported and observed behavior at
school. Our results suggest that even an intense and brief period of orchestral music
training is sufficient to facilitate the development of inhibitory control by modulating the
levels of self-reported hyperactivity. This research has implications for music pedagogy
and education especially in children with high hyperactivity. Future investigations will test
whether the findings can be extended to children diagnosed with ADHD
Opinione pubblica : cittadinanza, classe politica, democrazia
Una lunga tradizione non ha mai messo in dubbio che il concetto di \u201copinione\u201d indichi un complesso di ragioni e valutazioni centrate sul soggetto agente. L\u2019evidenza del concetto stava nella distinzione fra sapere certo (EPIST\uc9ME) e sapere di opinione (D
3XA). Tuttavia insita in questa distinzione vi \ue8 una sorta di paradosso: se l\u2019opinione pubblica fosse esclusivamente il prodotto dell\u2019interazione delle opinioni dei singoli individui nella sfera pubblica, stante la mutevolezza di queste opinioni, l\u2019opinione pubblica stessa sarebbe sempre oggetto di uno scarto temporale rispetto agli orientamenti degli individui sulle questioni di pubblica rilevanza. Con ci\uf2, \ue8 assai probabile che il solo modello interazionista non riesca a rendere pienamente conto delle dinamiche che contraddistinguono l\u2019opinione pubblica. Allo stesso tempo, per\uf2, la teoria della democrazia ci impone, quanto meno dal punto di vista normativo, uno stretto ancoraggio di ci\uf2 che costituisce opinione pubblica ai desideri e alle aspettative di cittadini razionali e informati. E\u2019 dipanabile questo dilemma, che peraltro vive di una duplice tensione fra normativo e positivo, fra ci\uf2 che l\u2019opinione pubblica \ue8 nell\u2019opinabile misurazione di sondaggisti e studiosi della comunicazione e ci\uf2 che l\u2019opinione pubblica dovrebbe essere dal punto di vista della teoria della democrazia? E\u2019 ancora possibile far vivere la metafora del cittadino razionale, consapevole, informato propria della tradizione liberal-democratica? Intendere l\u2019opinione pubblica come un\u2019osservazione del secondo ordine dovrebbe contribuire, da un lato, a superare gli attuali limiti che sperimentiamo nella comprensione di questo fenomeno e, dall\u2019altro, a preservare un\u2019idea di discussione su fatti di rilevanza pubblica proficua per un buon funzionamento della democrazia
GASP. XVI. Does cosmic web enhancement turn on star formation in galaxies?
Galaxy filaments are a peculiar environment, and their impact on the galaxy
properties is still controversial. Exploiting the data from the GAs Stripping
Phenomena in galaxies with MUSE (GASP), we provide the first characterisation
of the spatially resolved properties of galaxies embedded in filaments in the
local Universe. The four galaxies we focus on show peculiar ionised gas
distributions: Halpha clouds have been observed beyond four times the effective
radius. The gas kinematics, metallicity map and the ratios of emission line
fluxes confirm that they do belong to the galaxy gas disk, the analysis of
their spectra shows that very weak stellar continuum is associated to them.
Similarly, the star formation history and luminosity weighted age maps point to
a recent formation of such clouds. The clouds are powered by star formation,
and are characterised by intermediate values of dust absorption. We hypothesise
a scenario in which the observed features are due to "Cosmic Web Enhancement":
we are most likely witnessing galaxies passing through or flowing within
filaments that assist the gas cooling and increase the extent of the star
formation in the densest regions in the circumgalactic gas. Targeted
simulations are mandatory to better understand this phenomenon.Comment: MNRAS in press, 18 pages, 12 figure
Comunicazione politica e consenso democratico : un'applicazione di teoria dei giochi
Il rapporto fra informazione e razionalit\ue0 del comportamento elettorale resta un problema aperto. Le assunzioni introdotte dalla scelta razionale si sono dimostrare o teoricamente poco plausibili, o empiricamente troppo onerose. E le risposte a questo problema, da prospettive sia \uabinterne\ubb che \uabesterne\ubb alla scelta razionale, sono insoddisfacenti. I diversi tentativi di soluzione si ostinano a considerare l\u2019informazione come un dato, trascurando cos\uec i fattori connessi alla sua effettiva comprensione. Viceversa, come evidenziato dal concetto sistemico di doppia contingenza, l\u2019esistenza di aspettative reciproche circa il senso che individui in interazione possono attribuire ai rispettivi comportamenti non deve mai darsi per scontata. Il ricorso al concetto di doppia contingenza permette di interrogarsi sulle effettive condizioni che rendono possibile l\u2019esercizio di un comportamento elettorale razionale. La costruzione di un semplice modello di teoria dei giochi, in grado di descrivere la scelta di voto come il prodotto di una relazione di agenzia fra elettore e candidato in condizioni di doppia contingenza, porta infine alla luce il ruolo di fattori simbolici nel definire l\u2019orizzonte ideologico-culturale entro il quale si colloca il comportamento elettorale, senza con questo pregiudicare le potenzialit\ue0 applicative della scelta razionale
Enhanced star formation in both disks and ram pressure stripped tails of GASP jellyfish galaxies
Exploiting the data from the GAs Stripping Phenomena in galaxies with MUSE
(GASP) program, we compare the integrated Star Formation Rate- Mass relation
(SFR-M_ast) relation of 42 cluster galaxies undergoing ram pressure stripping
("stripping galaxies") to that of 32 field and cluster undisturbed galaxies.
Theoretical predictions have so far led to contradictory conclusions about
whether ram pressure can enhance the star formation in the gas disks and tails
or not and until now a statistically significant observed sample of stripping
galaxies was lacking. We find that stripping galaxies occupy the upper envelope
of the control sample SFR-M_ast relation, showing a systematic enhancement of
the SFR at any given mass. The star formation enhancement occurs in the disk
(0.2 dex), and additional star formation takes place in the tails. Our results
suggest that strong ram pressure stripping events can moderately enhance the
star formation also in the disk prior to gas removal.Comment: ApJL in pres
Spiral and irregular galaxies in the Hubble Deep Field North - Comparison with early types and implications for the global SFR density
We analyze a morphologically-selected complete sample of 52 late-type (spiral
and irregular) galaxies in the Hubble Deep Field North with total K-magnitudes
brighter than K=20.47. This sample exploits in particular the ultimate imaging
quality achieved by HST in this field, allowing us to clearly disentangle the
galaxy morphologies, based on accurate profiles of the surface brightness
distributions. Our purpose was to investigate systematic differences between
the two classes, as for colours, redshift distributions and ages of the
dominant stellar populations. This sample appears to miss significantly
galaxies above z=1.4 (in a similar way as an early-type galaxy sample
previously studied by us), a fact which may be explained as a global decline of
the underlying mass function for galaxies at these high redshifts. Differences
between early and late-types are apparent -particularly in the colour
distributions and the evolutionary star-formation (SF) rates per unit volume-,
although the complication in spectro-photometric modelling introduced by
dust-extinction in the gas-rich systems prevents us to reach conclusive results
on the single sources. However, we find that an integrated quantity like the
comoving star-formation rate density (SFR(t)) as a function of redshift is much
less affected by these uncertainties: by combining this with the previously
studied early-type galaxy sample, we find a shallower dependence of SFR(t) on z
between z=0.2 and z=1.5 than found by Lilly et al. (1995).Comment: 16 pages, 13 figures - Version accepted for publication in A&
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