3,032 research outputs found
Intrahepatic persistent fetal right umbilical vein: a retrospective study
Introduction: To appraise the incidence and value of intrahepatic persistent right umbilical vein (PRUV). Methods: This was a single-center study. Records of all women with a prenatal diagnosis of intrahepatic PRUV were reviewed. The inclusion criteria were women with gestational age greater than 13 weeks of gestation. Exclusion criteria were fetuses with situs abnormalities, due to the hepatic venous ambiguity, and extrahepatic PRUV. The primary outcome was the incidence of intrahepatic PRUV in our cohort. The secondary outcomes were associated malformations. Results: 219/57,079 cases (0.38%) of intrahepatic PRUV were recorded. The mean gestational age at diagnosis was 21.8 ± 2.9 weeks of gestations. PRUV was isolated in the 76.7%, while in 23.3% was associated with other major or minor abnormalities. The most common associated abnormalities were cardiovascular abnormalities (8.7%), followed by genitourinary abnormalities (6.4%), skeletal abnormalities (4.6%), and central nervous system abnormalities (4.1%). Within the cardiovascular abnormalities, the most common one was ventricular septal defect (six cases). Conclusion: In most cases PRUV is an isolated finding. Associated minor or major malformations are presented in the 23.3% of the cases, so this finding should prompt detailed prenatal assessment of the fetus, with particular regard to cardiovascular system
A Unification Free Introduction to Logic Programming
In this paper, we give a new presentation of the fundamental results of the theory of Logic Programming, which differs from classical introductions in at least two ways: the use of predicate algebras to deal with model theoretical aspects and the parameterization of the resolution algorithm with respect to the specific unification algorithm implemented
Minimum time control of heterodirectional linear coupled hyperbolic PDEs
We solve the problem of stabilization of a class of linear first-order
hyperbolic systems featuring n rightward convecting transport PDEs and m
leftward convecting transport PDEs. Using the backstepping approach yields
solutions to stabilization in minimal time and observer based output feedback
CERN openlab Whitepaper on Future IT Challenges in Scientific Research
This whitepaper describes the major IT challenges in scientific research at CERN and several other European and international research laboratories and projects. Each challenge is exemplified through a set of concrete use cases drawn from the requirements of large-scale scientific programs. The paper is based on contributions from many researchers and IT experts of the participating laboratories and also input from the existing CERN openlab industrial sponsors. The views expressed in this document are those of the individual contributors and do not necessarily reflect the view of their organisations and/or affiliates
The Ideal Candidate. Analysis of Professional Competences through Text Mining of Job Offers
The aim of this paper is to propose analytical tools for identifying peculiar aspects of job market for graduates. We propose a strategy for dealing with daa tat have different source and nature
Electrophoretic separation of large DNAs using steric confinement
We report an alternative method for electrophoretic separation of large DNAs
using steric confinement between solid walls, without gel or obstacles. The
change of electrophoretic mobility vs confinement thickness is investigated
using fluorescence video microscopy. We observe separation at small confinement
thicknesses followed by a transition to the bulk behaviour (no separation) at a
thickness of about 4 μm (a few radii of gyration for the studied DNA
chains). We present tentative explanations of our original observations.Comment: to appear in JCI
Control of Homodirectional and General Heterodirectional Linear Coupled Hyperbolic PDEs
Research on stabilization of coupled hyperbolic PDEs has been dominated by
the focus on pairs of counter-convecting ("heterodirectional") transport PDEs
with distributed local coupling and with controls at one or both boundaries. A
recent extension allows stabilization using only one control for a system
containing an arbitrary number of coupled transport PDEs that convect at
different speeds against the direction of the PDE whose boundary is actuated.
In this paper we present a solution to the fully general case, in which the
number of PDEs in either direction is arbitrary, and where actuation is applied
on only one boundary (to all the PDEs that convect downstream from that
boundary). To solve this general problem, we solve, as a special case, the
problem of control of coupled "homodirectional" hyperbolic linear PDEs, where
multiple transport PDEs convect in the same direction with arbitrary local
coupling. Our approach is based on PDE backstepping and yields solutions to
stabilization, by both full-state and observer-based output feedback,
trajectory planning, and trajectory tracking problems
Adsorption of polyampholytes on charged surfaces
We have studied the adsorption of neutral polyampholytes on model charged
surfaces that have been characterized by contact angle and streaming current
measurements. The loop size distributions of adsorbed polymer chains have been
obtained using atomic force microscopy (AFM) and compared to recent theoretical
predictions. We find a qualitative agreement with theory; the higher the
surface charge, the smaller the number of monomers in the adsorbed layer, in
agreement with theory. We propose an original scenario for the adsorption of
polyampholytes on surfaces covered with both neutral long-chain and charged
short-chain thiols.Comment: 11 pages, 17 figures, accepted for publication in EPJ
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