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The European Congenital Heart Surgeons Association (ECHSA) Congenital Database (CD) is the second largest clinical pediatric and congenital cardiac surgical database in the world and the largest in Europe, where various smaller national or regional databases exist. Despite the dramatic increase in interventional cardiology procedures over recent years, only scattered national or regional databases of such procedures exist in Europe. Most importantly, no congenital cardiac database exists in the world that seamlessly combines both surgical and interventional cardiology data on an international level; therefore, the outcomes of surgical and interventional procedures performed on the same or similar patients cannot easily be tracked, assessed, and analyzed. In order to fill this important gap in our capability to gather and analyze information on our common patients, ECHSA and The Association for European Paediatric and Congenital Cardiology (AEPC) have embarked on a collaborative effort to expand the ECHSA-CD with a new module designed to capture data about interventional cardiology procedures. The purpose of this manuscript is to describe the concept, the structure, and the function of the new AEPC Interventional Cardiology Part of the ECHSA-CD, as well as the potentially valuable synergies provided by the shared interventional and surgical analyses of outcomes of patients. The new AEPC Interventional Cardiology Part of the ECHSA-CD will allow centers to have access to robust surgical and transcatheter outcome data from their own center, as well as robust national and international aggregate outcome data for benchmarking. Each contributing center or department will have access to their own data, as well as aggregate data from the AEPC Interventional Cardiology Part of the ECHSA-CD. The new AEPC Interventional Cardiology Part of the ECHSA-CD will allow cardiology centers to have access to aggregate cardiology data, just as surgical centers already have access to aggregate surgical data. Comparison of surgical and catheter interventional outcomes could potentially strengthen decision processes. A study of the wealth of information collected in the database could potentially also contribute toward improved early and late survival, as well as enhanced quality of life of patients with pediatric and/or congenital heart disease treated with surgery and interventional cardiac catheterization across Europe and the world.
Transposition of great arteries with intact ventricular septum and left ventricular outflow tract obstruction (TGA + IVS + LVOTO) is uncommon. We reviewed operations performed in patients with TGA + IVS + LVOTO in the European Congenital Heart Surgeons Association Congenital Database (ECHSA-CD).
Methods:
All 109 patients with a diagnosis of TGA + IVS + LVOTO in ECHSA-CD who underwent cardiac surgery during a 21-year period (01/2000-02/2021, inclusive) were included. Preoperative variables, operative data, and postoperative outcomes were collected.
Results:
These 109 patients underwent 176 operations, including 37 (21.0%) arterial switch operations (ASO), 26 (14.2%) modified Blalock-Taussig-Thomas shunts (MBTTS), 11 (6.2%) Rastelli operations, and 13 (7.3%) other palliative operations (8 superior cavopulmonary anastomosis[es], 4 Fontan, and 1 other palliative procedure). Of 37 patients undergoing ASO, 22 had a concomitant procedure.
There were 68 (38.6%) reoperations, including 11 pacemaker procedures and 8 conduit operations. After a systemic-to-pulmonary artery shunt, reoperations included shunt reoperation (n = 4), Rastelli (n = 4), and superior cavopulmonary anastomosis (n = 3).
Overall Operative Mortality was 8.2% (9 deaths), including three following ASO, two following “Nikaidoh, Kawashima, or LV-PA conduit” procedures, and two following Rastelli. Postoperative complications occurred after 36 operations (20.4%). The most common complications were delayed sternal closure (n = 11), postoperative respiratory insufficiency requiring mechanical ventilation >7 days (n = 9), and renal failure requiring temporary dialysis (n = 8).
Conclusion:
TGA + IVS + LVOTO is rare (109 patients in ECHSA-CD over 21 years). ASO, MBTTS, and Rastelli are the most common operations performed for TGA + IVS + LVOTO. Larger international studies with long-term follow-up are needed to better define the anatomy of the LVOTO and to determine the optimal surgical strategy.
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favourable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of global (astrospheric), and local (atmospheric and surface) environments of exoplanets in the habitable zones (HZs) around G-K-M dwarf stars including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favourable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro)physical, chemical and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the HZ to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field in light of presentations and discussions during the NASA Nexus for Exoplanetary System Science funded workshop ‘Exoplanetary Space Weather, Climate and Habitability’ and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.
The study of molecules in space, known as astrochemistry or molecular astrophysics, is a rapidly growing field. Molecules exist in a wide range of environments in both gaseous and solid form, from our own solar system to the distant early universe. To astronomers, molecules are indispensable and unique probes of the physical conditions and dynamics of regions in which they are detected, especially the interstellar medium. In particular, the many stages of both low-mass and high-mass star formation are better understood today thanks to the analysis of molecular observations. Molecules can also yield a global picture of the past and present of sources. Moreover, molecules affect their environment by contributing to the heating and cooling processes that occur.
This paper presents the preparation of multi-walled carbone nanotubes (CNTs) and CdS nanoparticles based hybrid materials. We aim at comparing two kinds of CNTs’ functionalization by thiol groups in order to demonstrate that the surface chemistry done on the CNTs can direct the morphology of the nanohybrids. Indeed, strong oxidation of CNTs leads to shorter nanotubes opened at their ends, allowing the grafting of mercaptotriethoxysilane whereas the generation of diazonium salts in presence of pristine nanotubes should lead to the functionalization of the whole lateral surface of the nanotubes. CdS nanoparticles can then be anchored to thiol groups, leading to interesting hybrid precursors for photovoltaic applications.
We show that for ionization-driven chemistry in molecular clouds with very sub-solar (but non-vanishing) metallicities, OH replaces CO as the most abundant molecule containing at least one heavy element. Old Population-II stars, with observed metallicities ≲10-3times solar, may have formed in such OH-dominated star-forming clouds, shortly after the heavy elements were first produced at the epoch of reionization in the early Universe.
We have obtained high resolution spectra of the pre-main sequence binary system KH 15D (V582 Mon) while the star is fully visible, fully occulted, and during several ingress and egress events over the course of five contiguous observing seasons. The Hα line profile is a standard probe of the magnetospheric accretion flows on young stars such as KH 15D. We use these time series data to map out the size of the magnetosphere and find that it changes size from one observing season to the next.
The synthesis of organic molecular anions in TMC-1 and IRC+10216 is investigated. Modelled C2H−, CN−, C3N−, C5N− and C7N− column densities are sufficiently great that these species might be observable in IRC+10216. Density-enhanced shells in the outer envelope of IRC+10216 are found to enhance the C2H− and CN− column densities by shielding these anions from destruction by UV radiation. From a newly-derived upper column density limit of 6.6 × 1010 cm−2 for C2H− in IRC+10216 we deduce the primary production mechanism for this anion to be C2H2 + H− ⇒ C2H− + H2. In TMC-1, due to the low radiative electron attachment rates calculated for C2H−, CN− and CH2CN−, these species have modelled column densities below the detection threshold. They could, however, be produced in reactions we have not yet considered.
Microstructures and morphological features of a series of sintered quasicrystalline Al62.5−xCu25.3Fe12.2Bx alloys, with x ranging from 0 to 5 at.% were studied using x-ray diffraction, scanning electron microscopy, x-ray mapping, and electron probe microanalysis. Electron backscattering diffraction (EBSD) was also used to get information about the structures of some phases and identify the crystalline relationship in-between phases. Increasing x results in the change of the nature of extra phases. These secondary phases are all less than 1% in volume of the total matter except for the β phase at 5% of boron. Whatever the percentage of boron considered, boron seems to concentrate essentially in the parasite phases confirming doubts found in literature about the solubility of boron inside the face-centered-icosahedral Al–Cu–Fe phase. No special crystallographic relationship in between the tested phases could be spotted. EBSD is thus also confirmed as an excellent technique to get quasicrystalline grains orientations.
The Namaqua dune mole-rat Bathyergus janetta breeds seasonally, producing up to two litters during the early summer in the Cape. Females exhibit elevated urinary progesterone and oestradiol-17β concentrations and males raised concentrations of testosterone, these correlate with the onset of the seasonal winter rainfall. The rains moisten the soil allowing excavation and provide the mole-rats with the opportunity not only to extend burrow systems but also to search for mates. An increased incidence of hindfoot drumming and visitations to neighbouring burrow systems occurs during this period. Plural occupancy of burrows by adult mole-rats was found during the onset of the winter, and pups, lactating and pregnant females were caught at the end of October and November (early Cape summer). Pups develop rapidly and their eyes open after c. 1 week. Pup body mass increases exponentially from birth to about 70 days. Inter-sibling aggression increases progressively and after c. 60 days captive-born pups had to be separated, suggesting that in the wild they would have dispersed.
We present the results of a photometric monitoring program of pre-main sequence (PMS) stars in the young (2-4 Myr) open cluster NGC 2264 (d=700 pc). We find that the rotation periods are mass dependent and show a bimodal distribution for higher mass stars with M ≳ 0.3 M⊙ and a unimodal distribution for lower mass stars with M ≲ 0.3 M⊙.
We present a chemical model of the central torus around CRL 618 in order to confirm that long-chained hydrocarbons and benzene are formed at detectable abundances. We reproduce the observed abundances of these molecules comparatively well. We infer from our calculations that CRL 618 must be a young PPN, with a post-AGB age of approximately 600 yr.
The band structure of self-assembled Si/Ge quantum dot structures deposited by molecular beam epitaxy in the Stranski Krastanov growth mode is characterized by optical and electrical spectroscopy. Interband and intraband absorption, photocurrent, photoluminescence, Raman and admittance spectroscopy of structures with quantum dots of about 20 nm lateral size offer insight into the discrete level scheme within the valence band, the optical transitions and the lifetime of localized hole states. The results are discussed with respect to their possible applications in infrared light detection, storage and quantum-logic devices.
Colonies of the Mashona mole-rat Cryptomys darlingi are founded from a single reproductive pair of animals that are genetically unrelated by descent. All non-reproductive animals are the progeny of the reproductive pair. Non-reproductive colony members do not seem to be suppressed from reproduction at the level of the pituitary. In colonies in which the reproductive female is removed or dies, there is strict incest avoidance and the colony remains reproductively quiescent. Reinstatement of sexual activity in a queenless colony may be brought about in the laboratory by the introduction of unfamiliar and unrelated adult males. In the queenless colony under study, there was a marked change in the dominance hierarchy with an increase in Landau's index of linearity from 0.61 to 1.0 on the introduction of two unrelated males. The two new males became the most dominant within the colony. All previously non-reproductive females exhibited heightened urinary oestradiol 17β and progesterone concentrations on the introduction of the males. However, it was only the older and most dominant non-reproductive female that became the new reproductive female and produced a litter of three pups 70 days after the initial introduction.
The continuing controversies over media effects on public opinion and democracy can be traced in part to uncertainties about what public opinion is. “Public opinion” is a useful fiction that actually refers to several distinct phenomena, many of them crucially shaped by the current media system. The process of framing – selecting, highlighting, and sorting into a coherent narrative some facts or observations and deleting many others – is critical to the formation of this convenient fiction. Yet the framing process could be altered dramatically by new channels and processes of mediated communication. If that happens, public opinion as we have known it will likely be transformed, altering the way democracy has (imperfectly) worked since mass media became central to its operation. We shall differentiate public opinion, by which we mean the loose, usually undefined, and thoroughly protean term used by just about everyone from academics to journalists to citizens and politicans, from four referents that we define more precisely. Once we understand these distinctions we can understand better how current mass media influence politics, and how well the public gets represented in a democratic political process shaped by the traditional mass media. Profound changes in the media system now underway demand both far greater conceptual clarity and creative new means of getting at the theoretical concerns that underlie social scientists’ longstanding attention to the role of public opinion in democracy.
Those invoking public opinion seem usually to mean the comprehensive preferences of the majority of individuals on an issue.
In an attempt to overcome infections associated with central venous catheters, a new antiseptic central venous catheter coated with benzalkonium chloride on the internal and external surfaces has been developed and evaluated in a clinical trial. Patients (235) randomly received either a triple-lumen central venous catheter coated with benzalkonium chloride (117) or a polyurethane non-antiseptic catheter (118). The incidence of microbial colonization of both catheters and retained antiseptic activity of the benzalkonium chloride device following removal were determined. The benzalkonium chloride resulted in a significant reduction of the incidence of microbial colonization on both the internal and external catheter surfaces. The reduction in colonization was detected at both the intradermal (21 benzalkonium chloride catheters vs. 38 controls, P=0.0016) and distal segments of the antiseptic-coated catheters. Following catheter removal retained activity was demonstrated in benzalkonium chloride catheters which had been in place for up to 12 days. No patients developed adverse reactions to the benzalkonium chloride catheters. The findings demonstrate that the benzalkonium chloride catheter significantly reduced the incidence of catheter-associated colonization.
NGC 7026 is one of the most remarkable bipolar planetary nebulae in the northern sky. There is an increasing interest in sources of this kind, as they indicate that anisotropic outflow phenomena play a significant role in the final evolutionary stages of massive stars. To investigate the spatial distribution of the excitation conditions in this nebula, and to get information about the structure of the progenitor's red giant wind, we started a multi-wawelength survey taking high spatial resolution line images in the visible, near and mid-infrared range using the Calar Alto and UKIRT telescopes. The instruments used are the STScI optical coronograph (Paresce & Burrows, ESO Messanger 47, 1987), the MAGIC IR camera (Herbst et al., SPIE Proc. N.1946, p.605, 1993), and the new MPIA thermal IR imager MAX. We present here some preliminary results, which allows us to estimate the main physical parameters of the central star, to find evidence for significant shock emission at the polar regions of the nebula, and to reveal an unexpected deficit of H2 emission.
Laser ablation of silicon and germanium was carried out in moderate vacuum with l00fs to 400fs pulses at 248nm and intensities up to 3x1013 W/cm2. Evidence for non-thermal material removal was found. Imaged multishot ablation patterns display the intensity dependent self-structuring effect, forming well-known columnar structures. It is shown that continued irradiation of these structures eventually results in comparatively clean ablation. An increase of ablation rate with depth was observed. The reason is an intensity enhancement inside the pits by reflective focussing to a level where bond-breaking takes place. Furthermore, it was noticed that ablation contours can be significantly improved by electrically grounding the target.
The asymptotic behaviour of L2-solutions of one-body Schrödinger equations (–δ+V–E)ψ = 0 in ΩR = {x ∊ Rn||x|>R} is investigated. We show, for example, that if V tends to zero in a certain sense for |x|→∞, then either |x|γ exp for some γ>0 or ψ has compact support. Related results are given for potentials tending to infinity for |x|→∞.
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