451 research outputs found
Hiperaldosteronismo Primário Felino: Uma Enfermidade Endócrina Emergente
The primary hyperaldosteronism, an endocrine disease increasingly identified in cats, is characterized by adrenal gland dysfunction that interferes with the renin-angiotensin- aldosterone system, triggering the hypersecretion of aldosterone. Pathophysiological consequences of excessive aldosterone secretion are related to increased sodium and water retention, and increased excretion of potassium, which induce hypertension and severe hypokalemia, respectively. The most common clinical findings in cats include: polydipsia, nocturia, polyuria, generalized weakness, neck ventroflexion, syncope, anorexia, weight loss, pendulous abdomen and blindness. Diagnosis is based on the evidence of hormonal hypersecretion with suppression of renin release, imaging and histopathological evaluation of adrenal glands. Treatment may be curative with adrenalectomy, in cases of unilateral disease, or conservative, through administration of aldosterone antagonists, potassium supplementation and antihypertensives. Prognosis varies from fair to good with the appropriate therapy. This article reviews the main aspects of primary aldosteronism in cats, providing the clinician with important information for the diagnosis of this disease. © 2016, Universidade Federal de Santa Maria. All rights reserved.46468669
Exclusive processes in electron - ion collisions
The exclusive processes in electron-ion () interactions are an important
tool to investigate the QCD dynamics at high energies as they are in general
driven by the gluon content of the target, which is strongly subject to parton
saturation effects. In this paper we compute the cross sections for the
exclusive vector meson production as well as the deeply virtual Compton
scattering (DVCS) relying on the color dipole approach and considering the
numerical solution of the Balitsky-Kovchegov equation including running
coupling corrections (rcBK). The production cross sections obtained with the
rcBK solution and bCGC parametrization are very similar, the former being
slightly larger.Comment: 6 pages, 4 figure
Saturation physics at HERA and RHIC: An unified description
One of the frontiers of QCD which are intensely investigated in high energy
experiments is the high energy (small ) regime, where we expect to observe
the non-linear behavior of the theory. In this regime, the growth of the parton
distribution should saturate, forming a Color Glass Condensate (CGC). In fact,
signals of parton saturation have already been observed both in deep
inelastic scattering at HERA and in deuteron-gold collisions at RHIC.
Currently, the description of the experimental data of these experiments is
possible considering different phenomenological saturation models for the two
processes within the CGC formalism. In this letter we analyze the universality
of these dipole cross section parameterizations and verify that they are not
able to describe the HERA and RHIC data simultaneously. We analyze possible
improvements in the parameterizations and propose a new parametrization for the
forward dipole amplitude which allows us to describe quite well the small-
HERA data on structure function as well as the RHIC data on
charged hadron spectra. It is an important signature of the universality of the
saturation physics.Comment: 12 pages, 4 figures. Version to be published in Physics Letters
Constraining the nuclear gluon distribution in processes at RHIC
A systematic determination of the gluon distribution is of fundamental
interest in understanding the parton structure of nuclei and the QCD dynamics.
Currently, the behavior of this distribution at small (high energy) is
completely undefined. In this paper we analyze the possibility of constraining
the nuclear effects present in using the inclusive observables which
would be measured in the future electron-nucleus collider at RHIC. We
demonstrate that the study of nuclear longitudinal and charm structure
functions allows to estimate the magnitude of shadowing and antishadowing
effects in the nuclear gluon distribution.Comment: 6 pages, 3 eps figure
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Could saturation effects be visible in a future electron-ion collider?
We expect to observe parton saturation in a future electron - ion collider.
In this letter we discuss this expectation in more detail considering two
different models which are in good agreement with the existing experimental
data on nuclear structure functions. In particular, we study the predictions of
saturation effects in electron - ion collisions at high energies, using a
generalization for nuclear targets of the b-CGC model, which describes the
HERA quite well. We estimate the total, longitudinal and charm structure
functions in the dipole picture and compare them with the predictions obtained
using collinear factorization and modern sets of nuclear parton distributions.
Our results show that inclusive observables are not very useful in the search
for saturation effects. In the small region they are very difficult to
disentangle from the predictions of the collinear approaches . This happens
mainly because of the large uncertainties in the latter. On the other hand, our
results indicate that the contribution of diffractive processes to the total
cross section is about 20 % at large A and small Q^2, allowing for a detailed
study of diffractive observables. The study of diffractive processes becomes
essential to observe parton saturation.Comment: 7 pages 5 figure
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
- …