1,167 research outputs found
Transvenous Lead Extraction in Patients with Cardiac Implantable Device: The Impact of Systemic and Local Infection on Clinical Outcomes. An ESCâEHRA ELECTRa (European Lead Extraction Controlled) Registry Substudy
Background: Infections of cardiac implantable devices (CIEDI) have poor outcomes despite improvement in lead extraction (TLE) procedures. Methods: To explore the influence of CIEDI on the outcomes of TLE and the differences between patients with systemic (Sy) vs. local (Lo) CIEDI, we performed a subâanalysis of the EORP ELECTRa (European Lead Extraction ConTRolled) Registry. Results: Among 3555 patients enrolled by 73 centers in 19 Countries, the indication for TLE was CIEDI in 1850: 1170 with LoâCIEDI and 680 with SyâCIEDI. Patients with CIEDI had a worse inâhospital prognosis in terms of major complications (3.57% vs. 1.71%; p = 0.0007) and mortality (2.27% vs. 0.49%; p < 0.0001). SyâCIEDI was an independent predictor of inâhospital death (H.R. 2.14; 95%CI 1.06â4.33. p = 0.0345). Patients with SyâCIEDI more frequently had an initial CIED implant and a higher prevalence of comorbidities, while subjects with LoâCIEDI had a higher prevalence of previous CIED procedures. Time from signs of CIEDI and TLE was longer for LoâCIEDI despite a shorter preâTLE antibiotic treatment. Conclusions: Patients with CIEDI have a worse inâhospital prognosis after TLE, especially for patients with SyâCIEDI. These results raise the suspicion that in a relevant group of patients CIEDI can be systemic from the beginning without progression from LoâCIEDI. Future research is needed to characterize this subgroup of patients
Spin Glass Ordering in Diluted Magnetic Semiconductors: a Monte Carlo Study
We study the temperature-dilution phase diagram of a site-diluted Heisenberg
antiferromagnet on a fcc lattice, with and without the Dzyaloshinskii-Moriya
anisotropic term, fixed to realistic microscopic parameters for (IIB=Cd, Hg, Zn). We show that the dipolar Dzyaloshinskii-Moriya anisotropy
induces a finite-temperature phase transition to a spin glass phase, at
dilutions larger than 80%. The resulting probability distribution of the order
parameter P(q) is similar to the one found in the cubic lattice
Edwards-Anderson Ising model. The critical exponents undergo large finite size
corrections, but tend to values similar to the ones of the
Edwards-Anderson-Ising model.Comment: 4 pages plus 3 postscript figure
FREE ORAL COMMUNICATIONS 2: ALCOHOL AND LIVERâCLINICAL RESEARCHO2.1RAPID DECLINE OF LIVER STIFFNESS WITH ALCOHOL WITHDRAWAL IN HEAVY DRINKERS
Background and aims. Measurement of liver stiffness using real-time elastography appears as a promising tool to evaluate the severity of chronic liver diseases. Previous studies in patients with alcoholic liver disease have suggested that fibrosis was the only histological parameter to influence liver stiffness. To challenge this hypothesis, we have prospectively tested the short-term impact of alcohol withdrawal on liver stiffness value. Methods. All patients hospitalized for alcohol withdrawal in our Liver Unit between September 2008 and December 2010 had a liver stiffness determination (using a FibroScanÂź device) at entry (D0) and 7 days after alcohol withdrawal (D7). Stiffness values were compared using non-parametric test for paired-values. We compared (i) the 10 measures performed at D0 and at D7 for each patient; (ii) the variation of the median result of all patients (using Wilcoxon test in both cases). Results. A total of 138 patients were included in the study [median alcohol consumption: 150g/day (range: 40-400); hepatitis C: n=22 (15.9%); cirrhosis: n=29 (21.0%)]. From D0 to D7, the liver stiffness decreased significantly in 61 patients (44.2%) and increased significantly in 18 (13.0%). Considering all patients, median liver stiffness value decreased from 7.25 to kPa (P<0.001). The stage of fibrosis indicated by liver stiffness changed in 47 patients between D0 and D7 (decrease in 33 and increase in 14). Conclusion. Liver stiffness decreases significantly in nearly half of alcoholic patients after only 7 days of abstinence. This result strongly suggests that non-fibrotic lesions (such as inflammatory ones) may influence liver stiffness. From a practical point of view, it also shows that variation in alcohol consumption must be taken into account for the interpretation of liver stiffness valu
NIKA2: a mm camera for cluster cosmology
Galaxy clusters constitute a major cosmological probe. However, Planck 2015
results have shown a weak tension between CMB-derived and cluster-derived
cosmological parameters. This tension might be due to poor knowledge of the
cluster mass and observable relationship.
As for now, arcmin resolution Sunyaev-Zeldovich (SZ) observations ({\it e.g.}
SPT, ACT and Planck) only allowed detailed studies of the intra cluster medium
for low redshift clusters () high
resolution and high sensitivity SZ observations are needed. With both a wide
field of view (6.5 arcmin) and a high angular resolution (17.7 and 11.2 arcsec
at 150 and 260 GHz), the NIKA2 camera installed at the IRAM 30-m telescope
(Pico Veleta, Spain) is particularly well adapted for these observations. The
NIKA2 SZ observation program will map a large sample of clusters (50) at
redshifts between 0.5 and 0.9. As a pilot study for NIKA2, several clusters of
galaxies have been observed with the pathfinder, NIKA, at the IRAM 30-m
telescope to cover the various configurations and observation conditions
expected for NIKA2.
Nika2: A mm camera for cluster cosmology
Galaxy clusters constitute a major cosmological probe. However, Planck 2015 results have shown a weak tension between CMB-derived and cluster-derived cosmological parameters. This tension might be due to poor knowledge of the cluster mass and observable relationship. As for now, arcmin resolution Sunyaev-Zeldovich (SZ) observations (e.g. SPT, ACT and Planck) only allowed detailed studies of the intra cluster medium for low redshift clusters (z 0:5) high resolution and high sensitivity SZ observations are needed. With both a wide field of view (6.5 arcmin) and a high angular resolution (17.7 and 11.2 arcsec at 150 and 260 GHz), the NIKA2 camera installed at the IRAM 30-m telescope (Pico Veleta, Spain) is particularly well adapted for these observations. The NIKA2 SZ observation program will map a large sample of clusters (50) at redshifts between 0.5 and 0.9. As a pilot study for NIKA2, several clusters of galaxies have been observed with the pathfinder, NIKA, at the IRAM 30-m telescope to cover the various configurations and observation conditions expected for NIKA2
Continuous symmetry of C60 fullerene and its derivatives
Conventionally, the Ih symmetry of fullerene C60 is accepted which is
supported by numerous calculations. However, this conclusion results from the
consideration of the molecule electron system, of its odd electrons in
particular, in a close-shell approximation without taking the electron spin
into account. Passing to the open-shell approximation has lead to both the
energy and the symmetry lowering up to Ci. Seemingly contradicting to a
high-symmetry pattern of experimental recording, particularly concerning the
molecule electronic spectra, the finding is considered in the current paper
from the continuous symmetry viewpoint. Exploiting both continuous symmetry
measure and continuous symmetry content, was shown that formal Ci symmetry of
the molecule is by 99.99% Ih. A similar continuous symmetry analysis of the
fullerene monoderivatives gives a reasonable explanation of a large variety of
their optical spectra patterns within the framework of the same C1 formal
symmetry exhibiting a strong stability of the C60 skeleton.Comment: 11 pages. 5 figures. 6 table
Mapping the kinetic Sunyaev-Zel'dovich effect toward MACS J0717.5+3745 with NIKA
Measurement of the gas velocity distribution in galaxy clusters provides
insight into the physics of mergers, through which large scale structures form
in the Universe. Velocity estimates within the intracluster medium (ICM) can be
obtained via the Sunyaev-Zel'dovich (SZ) effect, but its observation is
challenging both in term of sensitivity requirement and control of systematic
effects, including the removal of contaminants. In this paper we report
resolved observations, at 150 and 260 GHz, of the SZ effect toward the triple
merger MACS J0717.5+3745 (z=0.55), using data obtained with the NIKA camera at
the IRAM 30m telescope. Assuming that the SZ signal is the sum of a thermal
(tSZ) and a kinetic (kSZ) component and by combining the two NIKA bands, we
extract for the first time a resolved map of the kSZ signal in a cluster. The
kSZ signal is dominated by a dipolar structure that peaks at -5.1 and +3.4
sigma, corresponding to two subclusters moving respectively away and toward us
and coincident with the cold dense X-ray core and a hot region undergoing a
major merging event. We model the gas electron density and line-of-sight
velocity of MACS J0717.5+3745 as four subclusters. Combining NIKA data with
X-ray observations from XMM-Newton and Chandra, we fit this model to constrain
the gas line-of-sight velocity of each component, and we also derive, for the
first time, a velocity map from kSZ data (i.e. that is model-dependent). Our
results are consistent with previous constraints on the merger velocities, and
thanks to the high angular resolution of our data, we are able to resolve the
structure of the gas velocity. Finally, we investigate possible contamination
and systematic effects with a special care given to radio and submillimeter
galaxies. Among the sources that we detect with NIKA, we find one which is
likely to be a high redshift lensed submillimeter galaxy.Comment: 19 pages, 9 figures, accepted in A&
The MUSE Hubble Ultra Deep Field Survey:II. Spectroscopic redshifts and comparisons to color selections of high-redshift galaxies
We have conducted a two-layered spectroscopic survey (1'x1' ultra deep and 3'x3' deep regions) in the Hubble Ultra Deep Field (HUDF) with the Multi Unit Spectroscopic Explorer (MUSE). The combination of a large field of view, high sensitivity, and wide wavelength coverage provides an order of magnitude improvement in spectroscopically confirmed redshifts in the HUDF; i.e., 1206 secure spectroscopic redshifts for HST continuum selected objects, which corresponds to 15% of the total (7904). The redshift distribution extends well beyond z>3 and to HST/F775W magnitudes as faint as ~30 mag (AB, 1-sigma). In addition, 132 secure redshifts were obtained for sources with no HST counterparts that were discovered in the MUSE data cubes by a blind search for emission-line features. In total, we present 1338 high quality redshifts, which is a factor of eight increase compared with the previously known spectroscopic redshifts in the same field. We assessed redshifts mainly with the spectral features [OII] at z~20% up to 28-29 mag and ~27 mag, respectively. We used the determined redshifts to test continuum color selection (dropout) diagrams of high-z galaxies. The selection condition for F336W dropouts successfully captures ~80% of the targeted z~2.7 galaxies. However, for higher redshift selections (F435W, F606W, and F775W dropouts), the success rates decrease to ~20-40%. We empirically redefine the selection boundaries to make an attempt to improve them to ~60%. The revised boundaries allow bluer colors that capture Lya emitters with high Lya equivalent widths falling in the broadbands used for the color-color selection. Along with this paper, we release the redshift and line flux catalog
Clinical added value of MRI to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO):study protocol for an international multicentre prospective diagnostic accuracy study
Abstract Background Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI. Methods In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in â„10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI. Discussion The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy. Trial registration The CAMINO study was registered in the Netherlands National Trial Register under number NL8039 on September 20th 2019
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