2015 Update on Acute Adverse Reactions to Gadolinium based Contrast Agents in Cardiovascular MR. Large Multi-National and Multi-Ethnical Population Experience With 37788 Patients From the EuroCMR Registry

Objectives: Specifically we aim to demonstrate that the results of our earlier safety data hold true in this much larger multi-national and multi-ethnical population. Background: We sought to re-evaluate the frequency, manifestations, and severity of acute adverse reactions associated with administration of several gadolinium- based contrast agents during routine CMR on a European level. Methods: Multi-centre, multi-national, and multi-ethnical registry with consecutive enrolment of patients in 57 European centres. Results: During the current observation 37788 doses of Gadolinium based contrast agent were administered to 37788 patients. The mean dose was 24.7 ml (range 5–80 ml), which is equivalent to 0.123 mmol/kg (range 0.01 - 0.3 mmol/kg). Forty-five acute adverse reactions due to contrast administration occurred (0.12 %). Most reactions were classified as mild (43 of 45) according to the American College of Radiology definition. The most frequent complaints following contrast administration were rashes and hives (15 of 45), followed by nausea (10 of 45) and flushes (10 of 45). The event rate ranged from 0.05 % (linear non-ionic agent gadodiamide) to 0.42 % (linear ionic agent gadobenate dimeglumine). Interestingly, we also found different event rates between the three main indications for CMR ranging from 0.05 % (risk stratification in suspected CAD) to 0.22 % (viability in known CAD). Conclusions: The current data indicate that the results of the earlier safety data hold true in this much larger multi-national and multi-ethnical population. Thus, the “off-label” use of Gadolinium based contrast in cardiovascular MR should be regarded as safe concerning the frequency, manifestation and severity of acute events

P3 amplitude reductions are associated with shared variance between internalizing and externalizing psychopathology

P3 amplitude reductions, commonly elicited in oddball paradigms, have been associated with both internalizing (e.g., depression and anxiety) and externalizing problems (e.g., substance use, aggression, and impulsivity). Recent factor analytic models have focused on the shared variance between internalizing and externalizing problems as a potentially important separable psychopathology construct (a general psychopathology factor, or p‐factor). To assess neurophysiological markers of this shared variance, we examined P3 amplitude to target and novel stimuli in an undergraduate sample with a range of internalizing and externalizing problems. Participants (N = 125) completed a rotated heads visual oddball paradigm, with IAPS pictures serving as infrequent novel stimuli. Results replicated P3 amplitude reduction relative to both target and novel stimuli separately for internalizing and externalizing problems, and found that the shared variance across internalizing and externalizing was significantly related to lower P3 amplitude to novels, targets, and a factor score of target and novel P3 measures. The present results are consistent with the interpretation that a general or shared problem behavior factor accounts for much of the associations between reduced P3 amplitude and internalizing and externalizing problems.There is a need for biological measures that can index emerging models of the shared variance between internalizing and externalizing problems (cf. general psychopathology factor, or p‐factor), to provide approaches for assessing the biological systems underlying these models. The current study found support for the idea that a general or shared problem behavior factor contributes to P3 amplitude reductions observed separately for internalizing and externalizing behaviors. This supports an inference that some biological systems are sensitive to processes associated with a shared problem behavior factor.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155993/1/psyp13618_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155993/2/psyp13618.pd

One-dimensional Josephson arrays as superlattices for single Cooper pairs

We investigate uniform one-dimensional arrays of small Josephson junctions ($E_J \ll E_C$, $E_C = (2e)^2/2C$) with a realistic Coulomb interaction $U(x) = E_C \lambda \exp( - |x|/\lambda)$ (here $\lambda \gg 1$ is the screening length in units of the lattice constant of the array). At low energies this system can be described in terms of interacting Bose particles (extra single Cooper pairs) on the lattice. With increasing concentration $\nu$ of extra Cooper pairs, a crossover from the Bose gas phase to the Wigner crystal phase and then to the superlattice regime occurs. The phase diagram in the superlattice regime consists of commensurable insulating phases with $\nu = 1/l$ ($l$ is integer) separated by superconducting regions where the current is carried by excitations with {\em fractional} electric charge $q = \pm 2e/l$. The Josephson current through a ring-shaped array pierced by magnetic flux is calculated for all of the phases.Comment: 4 pages (LATEX), 2 figure

CAVE Size Matters: Effects of Screen Distance and Parallax on Distance Estimation in Large Immersive Display Setups

International audienceWhen walking within a CAVE-like system, accommodation distance, parallax and angular resolution vary according to the distance between the user and the projection walls which can alter spatial perception. As these systems get bigger, there is a need to assess the main factors influencing spatial perception in order to better design immersive projection systems and virtual reality applications. Such analysis is key for application domains which require the user to explore virtual environments by moving through the physical interaction space. In this article we present two experiments which analyze distance perception when considering the distance towards the projection screens and parallax as main factors. Both experiments were conducted in a large immersive projection system with up to ten meter interaction space. The first experiment showed that both the screen distance and parallax have a strong asymmetric effect on distance judgments. We observed increased underestimation for positive parallax conditions and slight distance overestimation for negative and zero parallax conditions. The second experiment further analyzed the factors contributing to these effects and confirmed the observed effects of the first experiment with a high-resolution projection setup providing twice the angular resolution and improved accommodative stimuli. In conclusion, our results suggest that space is the most important characteristic for distance perception, optimally requiring about 6 to 7-meter distance around the user, and virtual objects with high demands on accurate spatial perception should be displayed at zero or negative parallax

Phase separation in supersolids

We study quantum phase transitions in the ground state of the two dimensional hard-core boson Hubbard Hamiltonian. Recent work on this and related models has suggested ``supersolid'' phases with simultaneous diagonal and off-diagonal long range order. We show numerically that, contrary to the generally held belief, the most commonly discussed ``checkerboard'' supersolid is thermodynamically unstable. Furthermore, this supersolid cannot be stabilized by next near neighbour interaction. We obtain the correct phase diagram using the Maxwell construction. We demonstrate the ``striped'' supersolid is thermodynamically stable and is separated from the superfluid phase by a continuous phase transition.Comment: 4 pages, 4 eps figures, include

Mean Field Theory of Josephson Junction Arrays with Charge Frustration

Using the path integral approach, we provide an explicit derivation of the equation for the phase boundary for quantum Josephson junction arrays with offset charges and non-diagonal capacitance matrix. For the model with nearest neighbor capacitance matrix and uniform offset charge $q/2e=1/2$, we determine, in the low critical temperature expansion, the most relevant contributions to the equation for the phase boundary. We explicitly construct the charge distributions on the lattice corresponding to the lowest energies. We find a reentrant behavior even with a short ranged interaction. A merit of the path integral approach is that it allows to provide an elegant derivation of the Ginzburg-Landau free energy for a general model with charge frustration and non-diagonal capacitance matrix. The partition function factorizes as a product of a topological term, depending only on a set of integers, and a non-topological one, which is explicitly evaluated.Comment: LaTex, 24 pages, 8 figure

Exact microscopic analysis of a thermal Brownian motor

We study a genuine Brownian motor by hard disk molecular dynamics and calculate analytically its properties, including its drift speed and thermal conductivity, from microscopic theory.Comment: 4 pages, 5 figure

Phase diagrams, critical and multicritical behavior of hard-core Bose-Hubbard models

We determine the zero-temperature phase diagram of the hard-core Bose-Hubbard model on a square lattice by mean-field theory supplemented by a linear spin-wave analysis. Due to the interplay between nearest and next-nearest neighbor interaction and cubic anisotropy several supersolid phases with checkerboard, stripe domain or intermediate symmetry are stabilized. The phase diagrams show three different topologies depending on the relative strength of nearest and next-nearest neighbor interaction. We also find a rich variety of new quantum critical behavior and multicritical points and discuss the corresponding effective actions and universality classes.Comment: 19 pages, ReVTeX, 18 figures included, submitted to PR

Low-energy quasiparticle states near extended scatterers in d-wave superconductors and their connection with SUSY quantum mechanics

Low-energy quasiparticle states, arising from scattering by single-particle potentials in d-wave superconductors, are addressed. Via a natural extension of the Andreev approximation, the idea that sign-variations in the superconducting pair-potential lead to such states is extended beyond its original setting of boundary scattering to the broader context of scattering by general single-particle potentials, such as those due to impurities. The index-theoretic origin of these states is exhibited via a simple connection with Witten's supersymmetric quantum-mechanical model.Comment: 5 page

Site-selective adsorption of naphthalene-tetracarboxylic-dianhydride on Ag(110): First-principles calculations

The mechanism of adsorption of the 1,4,5,8-naphthalene-tetracarboxylic-dianhydride (NTCDA) molecule on the Ag(110) surface is elucidated on the basis of extensive density functional theory calculations. This molecule, together with its perylene counterpart, PTCDA, are archetype organic semiconductors investigated experimentally over the past 20 years. We find that the bonding of the molecule to the substrate is highly site-selective, being determined by electron transfer to the LUMO of the molecule and local electrostatic attraction between negatively charged carboxyl oxygens and positively charged silver atoms in [1-10] atomic rows. The adsorption energy in the most stable site is 0.9eV. A similar mechanism is expected to govern the adsorption of PTCDA on Ag(110) as well.Comment: 8 pages, 4 figures, high-quality figures available upon reques