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Congenital heart defects (CHDs) occur in 8 of 1000 live-born children, making them common birth defects in the adolescent population. CHDs may have single gene, chromosomal, or multifactorial causes. Despite evidence that patients with CHD want information on heritability and genetics, no studies have investigated the interest or knowledge base in the adolescent population. This information is necessary as patients in adolescence take greater ownership of their health care and discuss reproductive risks with their physicians. The objectives of this survey-based study were to determine adolescents’ recall of their own heart condition, to assess patient and parent perception of the genetic contribution to the adolescent’s CHD, and to obtain information about the preferred method(s) for education. The results show that adolescent patients had good recall of their type of CHD. Less than half of adolescents and parents believed their CHD had a genetic basis or was heritable; however, adolescents with a positive family history of CHD were more likely to believe that their condition was genetic (p = 0.0005). The majority of patients were interested in receiving additional genetics education and preferred education in-person and in consultation with both parents and a physician. The adolescents who felt most competent to have discussions with their doctors regarding potential causes of their heart defect previously had a school science course which covered topics in genetics. These results provide insight into adolescents’ perceptions and understanding about their CHD and genetic risk and may inform the creation and provision of additional genetic education.
We present a multi-frequency study of the intermediate spiral SAB(r)bc type galaxy NGC 6744, using available data from the Chandra X-Ray telescope, radio continuum data from the Australia Telescope Compact Array and Murchison Widefield Array, and Wide-field Infrared Survey Explorer infrared observations. We identify 117 X-ray sources and 280 radio sources. Of these, we find nine sources in common between the X-ray and radio catalogues, one of which is a faint central black hole with a bolometric radio luminosity similar to the Milky Way’s central black hole. We classify 5 objects as supernova remnant (SNR) candidates, 2 objects as likely SNRs, 17 as H ii regions, 1 source as an AGN; the remaining 255 radio sources are categorised as background objects and one X-ray source is classified as a foreground star. We find the star-formation rate (SFR) of NGC 6744 to be in the range 2.8–4.7 M⊙~yr − 1 signifying the galaxy is still actively forming stars. The specific SFR of NGC 6744 is greater than that of late-type spirals such as the Milky Way, but considerably less that that of a typical starburst galaxy.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
Introduction: Data regarding adverse events (AEs) (unintended harm to the patient from health care provided) among children seen in the emergency department (ED) are scarce despite the high risk setting and population. The objective of our study was to estimate the risk and type of AEs, and their preventability and severity, among children treated in pediatric EDs. Methods: Our prospective cohort study enrolled children <18 years of age presenting for care during 21 randomized 8 hr-shifts at 9 pediatric EDs from Nov 2014 to October 2015. Exclusion criteria included unavailability for follow-up or insurmountable language barrier. RAs collected demographic, medical history, ED course, and systems level data. At day 7, 14, and 21 a RA administered a structured telephone interview to all patients to identify flagged outcomes (e.g. repeat ED visits, worsening/new symptoms, etc). A validated trigger tool was used to screen admitted patients’ health records. For any patients with a flagged outcome or trigger, 3 ED physicians independently determined if an AE occurred. Primary outcome was the proportion of patients with an AE related to ED care within 3 weeks of their ED visit. Results: We enrolled 6377 (72.0%) of 8855 eligible patients; 545 (8.5%) were lost to follow-up. Median age was 4.4 years (range 3 months to 17.9 yrs). Eight hundred and seventy seven (13.8%) were triaged as CTAS 1 or 2, 2638 (41.4%) as CTAS 3, and 2839 (44.7%) as CTAS 4 or 5. Top entrance complaints were fever (11.2%) and cough (8.8%). Flagged outcomes/triggers were identified for 2047 (32.1%) patients. While 252 (4.0%) patients suffered at least one AE within 3 weeks of ED visit, 163 (2.6%) suffered an AE related to ED care. In total, patients suffered 286 AEs, most (67.9%) being preventable. The most common AE types were management issues (32.5%) and procedural complications (21.9%). The need for a medical intervention (33.9%) and another ED visit (33.9%) were the most frequent clinical consequences. In univariate analysis, older age, chronic conditions, hospital admission, initial location in high acuity area of the ED, having >1 ED MD or a consultant involved in care, (all p<0.001) and longer length of stay (p<0.01) were associated with AEs. Conclusion: While our multicentre study found a lower risk of AEs among pediatric ED patients than reported among pediatric inpatients and adult ED patients, a high proportion of these AEs were preventable.
Selective serotonin reuptake inhibitors take several weeks to achieve their full antidepressant effects. Post-synaptic 5-HT2A receptor activation is thought to be involved in this delayed therapeutic effect. Pipamperone acts as a highly selective 5-HT2A/D4 antagonist when administered in low doses. The purpose of this study was to compare citalopram 40 mg once daily plus pipamperone 5 mg twice daily (PipCit) versus citalopram plus placebo twice daily for magnitude and onset of therapeutic effect.
An 8-week, randomized, double-blind study in patients with major depressive disorder was carried out.
The study population comprised 165 patients (citalopram and placebo, n=82; PipCit, n=83) with a mean baseline Montgomery–Asberg Depression Rating Scale (MADRS) score of 32.6 (s.d.=5.5). In the first 4 weeks, more citalopram and placebo than PipCit patients discontinued treatment (18% v. 4%, respectively, p=0.003). PipCit patients had significantly greater improvement in MADRS score at week 1 [observed cases (OC), p=0.021; last observation carried forward (LOCF), p=0.007] and week 4 (LOCF, p=0.025) but not at week 8 compared with citalopram and placebo patients. Significant differences in MADRS scores favoured PipCit in reduced sleep, reduced appetite, concentration difficulties and pessimistic thoughts. Mean Clinical Global Impression–Improvement scores were significantly improved after 1 week of PipCit compared with citalopram and placebo (OC and LOCF, p=0.002).
Although the MADRS score from baseline to 8 weeks did not differ between groups, PipCit provided superior antidepressant effects and fewer discontinuations compared with citalopram and placebo during the first 4 weeks of treatment, especially in the first week.
Immunohistochemistry and immunogold labelling techniques were used to localize the EG95 vaccine antigen in Echinococcus granulosus oncospheres. In non-activated oncospheres, the cytoplasm of 2 pairs of bilateral cells exhibited specific positive labelling for the presence of EG95. No surface localization was seen in non-activated or recently activated oncospheres. Besides the staining of 2 pairs of bilateral cells, there was also a generalized distribution of specific staining for EG95 throughout the parenchyma of activated oncospheres. Immunogold labelling of non-activated oncosphere revealed specific reactivity for EG95 involving 2 pairs of bilateral cells and the ultrastructural characteristics of these cells were consistent with them being penetration gland cells. No other oncospheral structures stained specifically for the presence of EG95. The absence of surface location of EG95 in oncospheres suggests that the parasite may not be susceptible to vaccine-induced antibody and complement mediated attack until some post-oncospheral development has occurred. Further studies would be required to determine when the EG95 antigen associates with the parasite's surface, thus making them susceptible to immune attack.
The excitation characteristics of the current-driven ion acoustic instability are studied, using a linearized kinetic model for a weakly ionized, unmagnetized plasma. Convective instability is predicted for typical low-pressure positive column conditions. The calculated spatial growth rates show a variation with frequency, which is similar to that of the amplitude variation with frequency of the self-excited instability measured in our positive column experiments in helium and argon. The comparison between theory and experiment indicates that ion Landau damping is significant for typical experimental conditions.
Some 2,000 orphaned chicks of African Penguins Spheniscus demersus were hand-reared and released back into the wild on Robben and Dassen Islands following the Treasure oil spill in June 2000. Of these chicks, 1,787 were flipper banded. This paper reports on the subsequent survival rate and breeding success of those individuals seen on Robben Island from 2001–2006. Survival to breeding age and their subsequent breeding success of hand-reared chicks was no different from that of naturally-reared chicks. Over a four-year period, pairs where at least one partner was a hand-reared chick produced an average of more than 1.6 chicks per year. Combining the data on survival with that on breeding success indicates that 1,000 hand-reared chicks will produce around 1,220 chicks themselves over their lifetimes, making this a worthwhile conservation intervention.
In our previous work  we investigated the impact of cold-crystallization on the structure of nanocomposites of PVDF with Lucentite STN™ OMS and observed the crossover composition in which the crystallographic beta phase dominated over alpha phase. Here, melt crystallization of PVDF/OMS nanocomposites was studied in the range of 0 to 1.0 wt% of OMS. In crystallization from melt, a decrease in crystallinity index occurs as a result of an increase in OMS. While beta phase fraction increased with an increase of OMS content in the range of interest, the amount of alpha crystals was found to be dominant even at high OMS compositions. At 1.0 wt% of OMS, beta crystals had reached at most 30% of the total crystallinity. Polarizing optical microscopy (POM) studies showed smaller, less birefringent spherulites with higher melting temperature compared to alpha spherulites appeared with OMS addition. Growth rate of these weakly birefringent spherulites is smaller than that of the strongly birefringent alpha spherulites. The increase in size and amount of the weakly birefringent spherulites with an increase of OMS and their higher melting point suggests these spherulites may be in the beta crystallographic phase.
The Keck Interferometer Nuller (KIN) is one of the major scientific and technical precursors to the Terrestrial Planet Finder Interferometer (TPF-I) mission. KIN's primary objective is to measure the level of exo-zodiacal mid-infrared emission around nearby main sequence stars, which requires deep broad-band nulling of astronomical sources of a few Janskys at 10 microns. A number of new capabilitites are needed in order to reach that goal with the Keck telescopes: mid-infrared coherent recombination, interferometric operation in “split pupil” mode, N-band optical path stabilization using K-band fringe tracking and internal metrology, and eventually, active atmospheric dispersion correction. We report here on the progress made implementing these new functionalities, and discuss the initial levels of extinction achieved on the sky.
Concerns about violent conduct of service users towards healthcare staff have prompted a ‘zero tolerance’ policy within the National Health Service. This policy specifically excludes users of mental health services. We attempt to challenge artificial distinctions between users of mental health and other services, and propose an ethical underpinning to the implementation of this policy.
Multiparticle diffusion equations were modeled to simulate the dynamics of phase coarsening. Local environmental information and particle interactions within the microstructure are included in our simulations. These studies reveal that the growth rates of particles with the same radii can differ, and that particles with the average radius can grow, shrink, or remain conditionally stable. These results are in contrast to mean-field predictions, where particle growth rates are strictly deterministic. Multiparticle simulations prove that fluctuations occur in the particle growth rates, even at extremely low microstructural densities. Multiplicative noise provides a good basis to describe microstructural fluctuations.
The behavior of H in p-GaN(Mg) at temperatures >400°C is modeled by using energies and vibration frequencies from density-functional theory to parameterize transport and reaction equations. Predictions agree semiquantitatively with experiment for the solubility, uptake, and release of the H when account is taken of a surface barrier.
Measurement of accurate positions, pulse periods and period derivatives is an essential follow-up to any pulsar survey. The procedures being used to obtain timing parameters for the pulsars discovered in the Parkes multibeam pulsar survey are described. Completed solutions have been obtained so far for about 80 pulsars. They show that the survey is preferentially finding pulsars with higher than average surface dipole magnetic fields. Eight pulsars have been shown to be members of binary systems and some of the more interesting results relating to these are presented.
Photoluminescence (PL) spectroscopy was carried out on a series of Si-doped bulk InGaN films in the low indium (In) composition regime. Room temperature PL showed a factor of 25 increase in integrated intensity as the In composition was increased from 0 to 0.07. Temperature dependent PL data was fit to an Arrhenius equation to reveal an increasing activation energy for thermal quenching of the PL intensity as the In composition is increased. Time resolved PL measurements revealed that only the sample with highest In (x=0.07) showed a strong spectral variation in decay time across the T=4K PL resonance, indicative of recombination from localized states at low temperatures. The decay times at room temperature were non-radiatively dominated for all films, and the room temperature (non-radiative) decay times increased with increasing In, from 50-230 psec for x=0-0.07. Our data demonstrate that non-radiative recombination is less effective with increasing In composition.
The Parkes multibeam pulsar survey uses a 13-element receiver operating at a wavelength of 20 cm to survey the inner Galactic plane with remarkable sensitivity. To date we have collected and analyzed data from 45% of the survey region (|b| < 5°; 260° < l < 50°), and have discovered 440 pulsars, in addition to re-detecting 190 previously known ones. Most of the newly discovered pulsars are at great distances, as inferred from a median dispersion measure (DM) of 400 cm−3 pc.
For p-type ion implanted SiC, temperatures in excess of 1600 °C are required to activate the dopant atoms and to reduce the crystal damage inherent in the implantation process. At these high temperatures, however, macrosteps (periodic welts) develop on the SiC surface. In this work, we investigate the use of a graphite mask as an anneal cap to eliminate the formation of macrosteps. N-type 4H- and 6H-SiC epilayers, both ion implanted with low energy (keV) Boron (B) schedules at 600 °C, and 6H-SiC substrates, ion implanted with Aluminum (Al), were annealed using a Graphite mask as a cap. The anneals were done at 1660 °C for 20 and 40 minutes. Atomic force microscopy (AFM), capacitance-voltage (C-V) and secondary ion mass spectrometry (SIMS) measurements were then taken to investigate the effects of the anneal on the surface morphology and the substitutional activation of the samples. It is shown that, by using the Graphite cap for the 1660 °C anneals, neither polytype developed macrosteps for any of the dopant elements or anneal times. The substitutional activation of Boron in 6H-SiC was about 15%.