704 research outputs found
Better adherence to the mediterranean diet could mitigate the adverse consequences of obesity on cardiovascular disease: The SUN prospective cohort
Strong observational evidence supports the association between obesity and
cardiovascular events. In elderly high-risk subjects, the Mediterranean diet (MedDiet) was reported
to counteract the adverse cardiovascular effects of adiposity. Whether this same attenuation
is also present in younger subjects is not known. We prospectively examined the association
between obesity and cardiovascular clinical events (myocardial infarction, stroke or cardiovascular
death) after 10.9 years follow-up in 19,065 middle-aged men and women (average age 38 year)
according to their adherence to the MedDiet (<6 points or ¥6 points in the Trichopoulou’s
Mediterranean Diet Score). We observed 152 incident cases of cardiovascular disease (CVD). An
increased risk of CVD across categories of body mass index (BMI) was apparent if adherence to the
MedDiet was low, with multivariable-adjusted hazard ratios (HRs): 1.44 (95% confidence interval:
0.93–2.25) for ¥25 – <30 kg/m2 of BMI and 2.00 (1.04–3.83) for ¥30 kg/m2 of BMI, compared to
a BMI < 25 kg/m2. In contrast, these estimates were 0.77 (0.35–1.67) and 1.15 (0.39–3.43) with
good adherence to MedDiet. Better adherence to the MedDiet was associated with reduced CVD
events (p for trend = 0.029). Our results suggest that the MedDiet could mitigate the harmful
cardiovascular effect of overweight/obesity
Air valves characterization. Intercomparison of tests procedures
En las operaciones de llenado y vaciado de las redes de riego, las ventosas juegan un papel fundamental ya que son las encargadas de eliminar el aire acumulado en las tuberías o, por el contrario, de introducir aire para sustituir el agua que va saliendo, ya sea de forma controlada o por una avería.
Durante el funcionamiento normal de la red, el aire atrapado en el sistema de distribución puede reducir la capacidad de transporte y ocasionar graves desperfectos.
Por todo ello, es de suma importancia seleccionar y ubicar correctamente estos equipos en función de los datos proporcionados por los fabricantes y los programas de dimensionamiento que hay en la actualidad.
Las normas UNE‐EN 1074‐4 “Válvulas para el suministro de agua. Requisitos de aptitud al uso y ensayos de verificación. Parte 4: Purgadores y ventosas” e ISO 9635‐4 “Agricultural irrigation equipment – Irrigation valves – Part 4: Air valves”, específica para riego, definen el procedimiento para caracterizar las ventosas y los purgadores.
En el caso del ensayo de expulsión, una fuente de presión introduce aire en la instalación, una instalación que debe cumplir con los requisitos establecidos en la norma. Dicha fuente de presión puede ser una soplante o un calderín a presión. En el caso del ensayo de admisión, el vacío en la instalación se puede simular creándolo a través de una soplante o con un calderín a presión. En este último caso, la ventosa se introduce en una cámara y se crea un caudal de aire del exterior al interior de la válvula generando una
presión positiva alrededor de la misma.
El Centro Nacional de Tecnología de Regadíos (CENTER), perteneciente al Ministerio de Agricultura, Pesca y Alimentación (MAPA), en colaboración con la Sociedad Mercantil Estatal de Infraestructuras Agrarias (SEIASA) ha organizado un ensayo de intercomparación en el que se han ensayado 8 ventosas DN100 de 4 modelos distintos en cuatro laboratorios de fabricantes que utilizan diferentes procedimientos de ensayo, con el objetivo de conocer si hay diferencias significativas entre los ensayos realizados con soplante y los ensayos realizados con calderín.
De ese modo, dichas diferencias se podrían tener en cuenta a la hora de establecer los requisitos normativos y, además, se podría definir si hay que aplicar alguna corrección en el caso de que se ensaye con un método o con otro. Las primeras conclusiones del estudio de intercomparación son:
1‐ En el caso del ensayo de expulsión de aire, los resultados obtenidos con soplante y con calderín son similares.
2‐ En el caso del ensayo de admisión de aire, los resultados de ensayo sí dependen del método de ensayo y, en el caso de utilizar calderín, dependen a su vez de:
a) Tamaño de la cámara donde se introduce la ventosa
b) Ubicación de la entrada de aire
c) Morfología de la ventosa
La revisión de la norma ISO 9635‐4 está abierta y se está trabajando en la realización de diferentes análisis para tratar de normalizar todas las variables y reflejarlo, inicialmente, en dicha norma
Longitudinal double-spin asymmetry for inclusive jet production in p+p collisions at sqrt(s)=200 GeV
We report a new STAR measurement of the longitudinal double-spin asymmetry
A_LL for inclusive jet production at mid-rapidity in polarized p+p collisions
at a center-of-mass energy of sqrt(s) = 200 GeV. The data, which cover jet
transverse momenta 5 < p_T < 30 GeV/c, are substantially more precise than
previous measurements. They provide significant new constraints on the gluon
spin contribution to the nucleon spin through the comparison to predictions
derived from one global fit of polarized deep-inelastic scattering
measurements.Comment: 7 pages, 4 figures + 1 tabl
Charge separation relative to the reaction plane in Pb-Pb collisions at TeV
Measurements of charge dependent azimuthal correlations with the ALICE
detector at the LHC are reported for Pb-Pb collisions at TeV. Two- and three-particle charge-dependent azimuthal correlations in
the pseudo-rapidity range are presented as a function of the
collision centrality, particle separation in pseudo-rapidity, and transverse
momentum. A clear signal compatible with a charge-dependent separation relative
to the reaction plane is observed, which shows little or no collision energy
dependence when compared to measurements at RHIC energies. This provides a new
insight for understanding the nature of the charge dependent azimuthal
correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286
Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
Measurements of multi-particle azimuthal correlations (cumulants) for charged
particles in p-Pb and Pb-Pb collisions are presented. They help address the
question of whether there is evidence for global, flow-like, azimuthal
correlations in the p-Pb system. Comparisons are made to measurements from the
larger Pb-Pb system, where such evidence is established. In particular, the
second harmonic two-particle cumulants are found to decrease with multiplicity,
characteristic of a dominance of few-particle correlations in p-Pb collisions.
However, when a gap is placed to suppress such correlations,
the two-particle cumulants begin to rise at high-multiplicity, indicating the
presence of global azimuthal correlations. The Pb-Pb values are higher than the
p-Pb values at similar multiplicities. In both systems, the second harmonic
four-particle cumulants exhibit a transition from positive to negative values
when the multiplicity increases. The negative values allow for a measurement of
to be made, which is found to be higher in Pb-Pb collisions at
similar multiplicities. The second harmonic six-particle cumulants are also
found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find
which is indicative of a Bessel-Gaussian
function for the distribution. For very high-multiplicity Pb-Pb
collisions, we observe that the four- and six-particle cumulants become
consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and
Pb-Pb are measured. These are found to be similar for overlapping
multiplicities, when a gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE
In this small note we are concerned with the solution of Forward-Backward
Stochastic Differential Equations (FBSDE) with drivers that grow quadratically
in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem
is a comparison result that allows comparing componentwise the signs of the
control processes of two different qgFBSDE. As a byproduct one obtains
conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio
System-Size Independence of Directed Flow Measured at the BNL Relativistic Heavy-Ion Collider
We measure directed flow (ν_1) for charged particles in Au+Au and Cu+Cu collisions at √S_(NN)=200 and 62.4 GeV, as a function of pseudorapidity (η), transverse momentum (p_t), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to ν_1 in different collision systems, and investigate possible explanations for the observed sign change in ν_1(p_t)
Spin alignment measurements of the and vector mesons at RHIC
We present the first spin alignment measurements for the and
vector mesons produced at mid-rapidity with transverse momenta up
to 5 GeV/c at = 200 GeV at RHIC. The diagonal spin density
matrix elements with respect to the reaction plane in Au+Au collisions are
= 0.32 0.04 (stat) 0.09 (syst) for the
( GeV/c) and = 0.34 0.02 (stat) 0.03
(syst) for the ( GeV/c), and are constant with transverse
momentum and collision centrality. The data are consistent with the unpolarized
expectation of 1/3 and thus no evidence is found for the transfer of the
orbital angular momentum of the colliding system to the vector meson spins.
Spin alignments for and in Au+Au collisions were also measured
with respect to the particle's production plane. The result,
= 0.41 0.02 (stat) 0.04 (syst), is consistent with that in p+p
collisions, = 0.39 0.03 (stat) 0.06 (syst), also
measured in this work. The measurements thus constrain the possible size of
polarization phenomena in the production dynamics of vector mesons.Comment: 7 pages, 4 figures. fig.1 updated; one more reference added, one typo
corrected, published in PRC.77.06190
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