University of Barcelona

About: University of Barcelona is a education organization based out in Barcelona, Spain. It is known for research contribution in the topics: Population & Transplantation. The organization has 46197 authors who have published 108576 publications receiving 3723377 citations. The organization is also known as: Universitat de Barcelona & UB.

Hepatopulmonary Syndrome — A Liver-Induced Lung Vascular Disorder

Abstract: The hepatopulmonary syndrome is characterized by defects in oxygenation due to pulmonary abnormalities associated with chronic liver disease. Dyspnea and hypoxemia can be severe and often worsen in the upright position. Gross dilatation of the precapillary and capillary vessels occurs with ventilation–perfusion mismatch. The syndrome usually improves after liver transplantation.

Magnetic resonance for assessment of disease activity and severity in ileocolonic Crohn’s disease

Abstract: Objective: Assessment of disease extension and activity is crucial to guide treatment in Crohn’s disease. The objective of the current cross-sectional study was to determine the accuracy of MR for this assessment. Design: 50 patients with clinically active (n = 35) or inactive (n = 15) Crohn’s disease underwent ileocolonoscopy (reference standard) and MR. T2-weighted and precontrast and postcontrast-enhanced T1-weighted sequences were acquired. Endoscopic activity was evaluated by CDEIS (Crohn’s Disease Endoscopic Index of Severity); in addition endoscopic lesions were classified as absent, mild (inflammation without ulcers) or severe (presence of ulceration). Results: The comparison of intestinal segments with absent, mild and severe inflammation demonstrated a progressive and significant (p Conclusion: The accuracy of MR for detecting disease activity and assessing severity brings about the possibility of using MR as an alternative to endoscopy in the evaluation of ileocolonic Crohn’s disease.

The paradigm of body condition: a critical reappraisal of current methods based on mass and length

Abstract: Summary 1. Body condition is a major concept in ecology addressed in countless studies, and a variety of non-destructive methods are used to estimate the condition of individuals based on the relationship between body mass M and measures of length L. There is currently no consensus about the most appropriate condition index (CI) method, and various traditions have been established within subdisciplines in which ecologists tend to apply that method used previously by their peers. 2. Here, we present a reappraisal of six conventional CI methods: Fulton’s index (K = M/L3), Quetelet’s index (BMI = M/L2), Relative condition (Kn, computed as the observed individual mass divided by the predicted mass Mi* = a Lib where a and b are determined by ordinary least squares (OLS) regression of M against L), Relative mass (Wr, where a and b above are determined from a reference population), the Residual index (Ri, the residuals from an OLS regression of M against L) and ancova. We compare the performance of these methods with that of the Scaled mass index, a novel method which was previously shown to perform better than Ri as a predictor of fat and other body components [J. Peig & A.J. Green (2009) Oikos, 118, 1883]. 3. To be reliable, a CI method must successfully account for the changing relationship between M and L as body size changes and growth occurs (i.e. for the scaling relationship between M and L). Using data from three species of small mammals we show that, unlike the Scaled mass index, all six conventional methods fail to do this, and as a result they consistently lead to significant differences in CIs between age classes and sex that are a mere consequence of changes in body size. The Scaled mass index was also particularly successful at detecting changes in CI resulting from high levels of contaminants.

Description and performance of track and primary-vertex reconstruction with the CMS tracker

Abstract: A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tt events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p_T > 0.9GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p_T = 100GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p_T, and respectively, 10μm and 30μm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10–12μm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.