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There are a variety of causes of acute heart failure in children including myocarditis, genetic/metabolic conditions, and congenital heart defects. In cases with a structurally normal heart and a negative personal and family history, myocarditis is often presumed to be the cause, but we hypothesise that genetic disorders contribute to a significant portion of these cases. We reviewed our cases of children who presented with acute heart failure and underwent genetic testing from 2008 to 2017. Eighty-seven percent of these individuals were found to have either a genetic syndrome or pathogenic or likely pathogenic variant in a cardiac-related gene. None of these individuals had a personal or family history of cardiomyopathy that was suggestive of a genetic aetiology prior to presentation. All of these individuals either passed away or were listed for cardiac transplantation indicating genetic testing may provide important information regarding prognosis in addition to providing information critical to assessment of family members.
Growth mixture modeling with a sample of 749 Mexican heritage families identified parallel trajectories of adolescents’ and their mothers’ heritage cultural values and parallel trajectories of adolescents’ and their fathers’ heritage cultural values from Grades 5 to 10. Parallel trajectory profiles were then used to test cultural gap-distress theory that predicts increased parent–adolescent conflict and adolescent psychopathology over time when adolescents become less aligned with Mexican heritage values compared to their parents. Six similar parallel profiles were identified for the mother–youth and father–youth dyads, but only one of the six was consistent with the hypothesized problem gap pattern in which adolescents’ values were declining over time to become more discrepant from their parents. When compared to families in the other trajectory groups as a whole, mothers in the mother–adolescent problem gap trajectory group reported higher levels of mother–adolescent conflict in the 10th grade that accounted for subsequent increases in internalizing and externalizing symptoms assessed in 12th grade. Although the findings provided some support for cultural gap-distress predictions, they were not replicated with adolescent report of conflict nor with the father–adolescent trajectory group analyses. Exploratory pairwise comparisons between all six mother–adolescent trajectory groups revealed additional differences that qualified and extended these findings.
Firefighters represent an important population for understanding the consequences of exposure to potentially traumatic stressors.
The researchers were interested in the effects of pre-employment disaster exposure on firefighter recruits’ depression and posttraumatic stress disorder (PTSD) symptoms during the first three years of fire service and hypothesized that: (1) disaster-exposed firefighters would have greater depression and PTSD symptoms than non-exposed overall; and (2) depression and PTSD symptoms would worsen over years in fire service in exposed firefighters, but not in their unexposed counterparts.
In a baseline interview, 35 male firefighter recruits from seven US cities reported lifetime exposure to natural disaster. These disaster-exposed male firefighter recruits were matched on age, city, and education with non-exposed recruits.
A generalized linear mixed model revealed a significant exposure×time interaction (ecoef =1.04; P<.001), such that depression symptoms increased with time for those with pre-employment disaster exposure only. This pattern persisted after controlling for social support from colleagues (ecoefficient=1.05; P<.001), social support from families (ecoefficient=1.04; P=.001), and on-the-job trauma exposure (coefficient=0.06; ecoefficient=1.11; P<.001). Posttraumatic stress disorder symptoms did not vary significantly between exposure groups at baseline (P=.61).
Depression symptoms increased with time for those with pre-employment disaster exposure only, even after controlling for social support. Posttraumatic stress disorder symptoms did not vary between exposure groups.
PenningtonML, CarpenterTP, SynettSJ, TorresVA, TeagueJ, MorissetteSB, KnightJ, KamholzBW, KeaneTM, ZimeringRT, GulliverSB. The Influence of Exposure to Natural Disasters on Depression and PTSD Symptoms among Firefighters. Prehosp Disaster Med. 2018;33(1):102–108.
The ice-sheet margin at Russell Glacier, West Greenland, advanced ∼7 m a−1 between 1968 and 1999. As the ice advanced over moraine ridges, small changes in position caused major changes in the routing of proglacial water and sediment. These included changes in the distribution of ice-marginal lakes, in the periodic drainage of ice-dammed lakes, in the routing and sediment content of meltwater draining into the proglacial zone, and in the release of sediment from the moraines by erosion and mass movements. Proglacial hydrology and sediment flux appear to be controlled not simply by glacier mass balance, but by evolving ice-marginal geomorphology, which must be accounted for in palaeoenvironmental interpretation of proglacial sediments.
Sediment production at a terrestrial section of the ice-sheet margin in West Greenland is dominated by debris released through the basal ice layer. The debris flux through the basal ice at the margin is estimated to be 12–45 m3 m−1 a−1. This is three orders of magnitude higher than that previously reported for East Antarctica, an order of magnitude higher than sites reported from in Norway, Iceland and Switzerland, but an order of magnitude lower than values previously reported from tidewater glaciers in Alaska and other high-rate environments such as surging glaciers. At our site, only negligible amounts of debris are released through englacial, supraglacial or subglacial sediment transfer. Glaciofluvial sediment production is highly localized, and long sections of the ice-sheet margin receive no sediment from glaciofluvial sources. These findings differ from those of studies at more temperate glacial settings where glaciofluvial routes are dominant and basal ice contributes only a minor percentage of the debris released at the margin. These data on debris flux through the terrestrial margin of an outlet glacier contribute to our limited knowledge of debris production from the Greenland ice sheet.
We describe a space VLBI experiment involving an earth-orbiting satellite (SURFSAT) and simulated satellites, a space VLBI ground tracking station, an array of ground radio telescopes, and a space VLBI correlator. The purpose of this experiment was to provide as complete as possible an end-to-end simulation of space VLBI in preparation for the first space VLBI mission, VSOP, and in particular to test the most critical aspect of space VLBI, viz. the ability to generate a stable and accurate frequency standard (clock) for the orbiting VLBI element.
The response of Grapholita molesta (Busck) males to three-component sex pheromone blends containing a 100% ratio of the major sex pheromone component, (Z)-8-dodecenyl acetate and a 10% ratio of (Z)-8-dodecenol, but with varying ratios of (E)-8-dodecenyl acetate (0.4, 5.4, 10.4, 30.4, and 100.1% E-blends) was tested with populations in eight stone and pome fruit orchards in Europe, Asia, and North and South America. Traps baited with the 5.4% E-blend caught significantly more males than traps with any other blend with all populations. Significantly more males were caught in traps baited with the 10.4% E-blend than in traps with the remaining blends, except with the 0.4% E-blend in Turkey. Significant differences in male moth catches occurred between the other blends with the 0.4>30.4% E-blend, and the 30.4>100.1% E-blend. Male moth catches with the 100.1% E-blend only differed from the hexane control in Chile. No apparent differences were noted to these blends in populations collected from pome or stone fruits. Flight tunnel assays to synthetic blends with a subset of populations were similar to the field results, but the breadth of the most attractive E-blends was wider. Flight tunnel assays also demonstrated a high level of male–female cross-attraction among field-collected populations. Female gland extracts from field-collected populations did not show any significant variation in their three-component blends. The only exceptions in these assays were that long-term laboratory populations were less responsive and attractive, and produced different blend ratios of the two minor components than recently collected field populations.
We report a preliminary study on the influence of indium doping on ultra-thin film silicon solar cells. The design of the cell reported here is such that it should elucidate the impact of the indium dopant, which is concentrated in the thin film. Indium, a deep level in silicon (0.157 eV above the valence band), acts as a p-type dopant and a sensitizer. Absorption through sub-bandgap transitions is expected based on the previously reported Impurity PhotoVoltaic (IPV) Effect . It is proposed that the implementation of a novel vertical PN junction configuration together with the IPV effect enhances the efficiency of ultra-thin solar cells. The most efficient cell fabricated to date, in our research group, has a conversion efficiency of 4.3 % (active silicon thickness of 2.5 μm), a short-circuit current density of 14.9 mA/cm2 and an open-circuit voltage of 0.51 V under 1 sun illumination. The cell has not been optimized with any type of light trapping technique and 11.24 % of the cell surface is covered by the metal contacts. Numerical simulation indicates that for the geometry used, the maximum efficiency that may be expected is 9.8 % (compared to the 4.3 % measured).
Shepherdson  showed that for a discrete ordered ring I, I is a model of I Open iff I is an integer part of a real closed ordered field. In this paper, we consider integer parts satisfying PA. We show that if a real closed ordered field R has an integer part I that is a nonstandard model of PA (or even IΣ4), then R must be recursively saturated. In particular, the real closure of I, RC (I), is recursively saturated. We also show that if R is a countable recursively saturated real closed ordered field, then there is an integer part I such that R = RC(I) and I is a nonstandard model of PA.
The effects of post-implant anneal conditions on the level of residual damage resulting from nitrogen and boron implants after different anneal processes are investigated using the Positron Annihilation Spectroscopy (PAS) technique. It is shown that after implantation there is a substantial defect concentration significantly below the range of the implants. However such damage is almost completely recovered after anneal in contrast with the damage close to the implant range point. Such residual damage has a strong effect on the electrical characteristics of double implanted bipolar transistors - principally though reduction in carrier mobility and lifetime. It is shown that the precise implant and anneal conditions play a strong role in the level of such damage and the subsequent electrical performance of bipolar devices.
Progressive annealing of a-Si:D and a-Si:DH samples between 250 and 600°C is found to eliminate the broad central deuteron magnetic resonance (DMR) spectral component associated with weakly bonded D. The well-resolved doublet arising from tightly bound D diminishes in intensity. The narrow central line associated with microvoid-contained molecular D2 and HD increases and then decreases for the warmest anneals. DMR relaxation times, line shapes, and hole-burning spectra reflect changes in sample morphology upon annealing.
The edge termination of SiC by the implantation of an inert ion species is used widely to increase the breakdown voltage of high power devices. We report results of the edge termination of Schottky barrier diodes using 30keV Ar+ ions with particular emphasis on the role of postimplant, relatively low temperature, annealing. The device leakage current measured at 100V is increased from 2.5nA to 7μA by the implantation of 30keV Ar+ ions at a dose of 1×1015 cm−2. This is reduced by two orders of magnitude following annealing at 600°C for 60 seconds, while a breakdown voltage in excess of 750V is maintained. The thermal evolution of the defects introduced by the implantation was monitored using positron annihilation spectroscopy (PAS) and deep-level-transient spectroscopy (DLTS). While a concentration of open-volume defects in excess of 1×1019cm−3 is measured using PAS in all samples, electrically active trapping sites are observed at concentrations ∼1×1015cm−3 using DLTS. The trap level is well-defined at Ec−Et = 0.9eV.
The development of monolithic silicon photonic systems has been the subject of intense research over the last decade. In addition to passive waveguiding structures suitable for DWDM applications, integration of electrical and optical functionality has yielded devices with the ability to dynamically attenuate, switch and modulate optical signals. Despite this significant progress, much higher levels of integration and increased functionality are required if silicon is to dominate as a substrate for photonic circuit fabrication as it does in the microelectronic industry. In particular, there exists a requirement for efficient silicon-based optical sources and detectors which are compatible with wavelengths of 1.3 and 1.5μm. While a great deal of work has focussed on the development of silicon-based optical sources, there has been less concentrated effort on the development of a simple, easily integrated detector technology. We describe here the design, fabrication and characterization of a wholly monolithic silicon waveguide optical detector, utilizing an integrated p+-u-n+ diode, which has significant response to optical signals at the communication wavelength of 1.54μm. Measurable infra-red response is induced via the controlled introduction of mid-gap electronic levels within the rib waveguide. This approach is completely compatible with ULSI fabrication. The requirement for the detectors to be integrated with a rib waveguide and hence the guarantee of a long optical signal-device interaction, results in electrical signals of several μAs, even for deep-levels with a small optical absorption cross-section. Further, the rise and fall time of the detectors is compatible with current monolithic, silicon device based, optical switching and modulation operating in the MHz regime. These results suggest that these detectors offer a cost-effective route to signal monitoring in integrated photonic circuits.
In a factory population the occurrence of reactions to tetanus toxoid was recorded after 6740 injections. The incidence of general reactions was 0·3 % and of local reactions 2·6%. The local reaction rate to the first injection of the basic immunization course was 0·9%, to the second injection 2·7%, and to the third injection 7·4%. To booster injections the rate was 1·6%. The local reaction rate was appreciably higher in women than in men – 14·4 % and 5·7 % respectively in the case of the third injection – and the incidence among women increased with age.
Tetanus vaccine containing 10 Lf of toxoid caused fewer reactions than one containing 20 Lf, but a reduction in the content of aluminium adjuvant did not affect the reaction rate.
Almost all reactors were found to have a satisfactory serum antitoxin concentration at the time of the reaction or developed a satisfactory immunity within 1–6 months.
Skin tests were made in 32 hypersensitive patients. Neither the diluent, thiomersal preservative, nor the culture medium appeared to be responsible for hypersensitivity. The degree of hypersensitivity elicited by a special highly purified toxoid was only very slightly less than that elicited by the commercially pure toxoid. It is suggested that reactions are largely due to the toxoid antigen itself rather than to impurities or other components of the vaccine.