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There is now a strong body of literature showing that bullying victimisation during childhood and adolescence precedes the later development of anxiety and depressive disorders. This study aimed to quantify the burden of anxiety and depressive disorders attributable to experiences of bullying victimisation for the Australian population.
This study updated a previous systematic review summarising the longitudinal association between bullying victimisation and anxiety and depressive disorders. Estimates from eligible studies published from inception until 18 August 2018 were included and meta-analyses were based on quality-effects models. Pooled relative risks were combined with a contemporary prevalence estimate for bullying victimisation for Australia in order to calculate population attributable fractions (PAFs) for the two mental disorder outcomes. PAFs were then applied to estimates of the burden of anxiety and depressive disorders in Australia expressed as disability-adjusted life years (DALYs).
The findings from this study suggest 7.8% of the burden of anxiety disorders and 10.8% of the burden of depressive disorders are attributable to bullying victimisation in Australia. An estimated 30 656 DALYs or 0.52% (95% uncertainty interval 0.33–0.72%) of all DALYs in both sexes and all ages in Australia were attributable to experiences of bullying victimisation in childhood or adolescence.
There is convincing evidence to demonstrate a causal relationship between bullying victimisation and mental disorders. This study showed that bullying victimisation contributes a significant proportion of the burden of anxiety and depressive disorders. The investment and implementation of evidence-based intervention programmes that reduce bullying victimisation in schools could reduce the burden of disease arising from common mental disorders and improve the health of Australians.
The baseline of East-West array of the Fleurs Synthesis Telescope (FST) has been extended from 786 metres to 1585 metres by the addition of two 13.7 metre dishes. A digital receiver has been built to accommodate the extra delay and correlation requirements, low noise FET preamplifiers have been installed on the large antennas, and a software package has been developed for processing observation data on a VAX 11/780. The FST is now capable of producing accurate wide field maps at 1415 MHz with a resolution of 20 arc seconds and a sensitivity of several milliJansky.
Interventions that prevent healthcare-associated infection should lead to fewer deaths and shorter hospital stays. Cleaning hands (with soap or alcohol) is an effective way to prevent the transmission of organisms, but rates of compliance with hand hygiene are sometimes disappointingly low. The National Hand Hygiene Initiative in Australia aimed to improve hand hygiene compliance among healthcare workers, with the goal of reducing rates of healthcare-associated infection.
We examined whether the introduction of the National Hand Hygiene Initiative was associated with a change in infection rates. Monthly infection rates for healthcare-associated Staphylococcus aureus bloodstream infections were examined in 38 Australian hospitals across 6 states. We used Poisson regression and examined 12 possible patterns of change, with the best fitting pattern chosen using the Akaike information criterion. Monthly bed-days were included to control for increased hospital use over time.
The National Hand Hygiene Initiative was associated with a reduction in infection rates in 4 of the 6 states studied. Two states showed an immediate reduction in rates of 17% and 28%, 2 states showed a linear decrease in rates of 8% and 11% per year, and 2 showed no change in infection rates.
The intervention was associated with reduced infection rates in most states. The failure in 2 states may have been because those states already had effective initiatives before the national initiative’s introduction or because infection rates were already low and could not be further reduced.
We detail the rich molecular story of NGC 1266, its serendipitous discovery within the ATLAS3D survey (Cappellari et al. 2011) and how it plays host to an AGN-driven molecular outflow, potentially quenching all of its star formation (SF) within the next 100 Myr. While major mergers appear to play a role in instigating outflows in other systems, deep imaging of NGC 1266 as well as stellar kinematic observations from SAURON, have failed to provide evidence that NGC 1266 has recently been involved in a major interaction. The molecular gas and the instantaneous SF tracers indicate that the current sites of star formation are located in a hypercompact disk within 200 pc of the nucleus (Fig. 1; SF rate ≈ 2 M⊙ yr−1). On the other hand, tracers of recent star formation, such as the Hβ absorption map from SAURON and stellar population analysis show that the young stars are distributed throughout a larger area of the galaxy than current star formation. As the AGN at the center of NGC 1266 continues to drive cold gas out of the galaxy, we expect star formation rates to decline as the star formation is ultimately quenched. Thus, NGC 1266 is in the midst of a key portion of its evolution and continued studies of this unique galaxy may help improve our understanding of how galaxies transition from the blue to the red sequence (Alatalo et al. 2011).
NGC 1266 is a nearby field galaxy observed as part of the ATLAS3D survey (Cappellari et al. 2011). NGC 1266 has been shown to host a compact (< 200 pc) molecular disk and a mass-loaded molecular outflow driven by the AGN (Alatalo et al. 2011). Very Long Basline Array (VLBA) observations at 1.65 GHz revealed a compact (diameter < 1.2 pc), high brightness temperature continuum source most consistent with a low-level AGN origin. The VLBA continuum source is positioned at the center of the molecular disk and may be responsible for the expulsion of molecular gas in NGC 1266. Thus, the candidate AGN-driven molecular outflow in NGC 1266 supports the picture in which AGNs do play a significant role in the quenching of star formation and ultimately the evolution of the red sequence of galaxies.
Hierarchically porous materials are of interest in a wide range of applications. If the materials are electronic, or ionic conductors, such materials are of interest as electrodes for use in fuel cells. Using hierarchically porous silica as templates, we have demonstrated the formation of hierarchically porous metal and metal oxide structures. Through the control of the synthesis conditions, we have produced partial replicas ca. 1 cubic centimeter in volume, in which two macroporous networks are separated by a nanoporous membrane. The macroporous network in the silica template is known to be bicontinuous. Our underlying model predicts that the second, induced, macroporous network should be similarly bicontinuous.
Micrometer resolution X-ray tomography of the whole sample confirms that the synthesis produces one bicontinuous macroporous network, and is consistent with the existence of a second set of macropores. Preliminary experiments were carried out using FIB/SEM serial tomography to image the second macropore network, however, the length scale of the structures is such that this approach it is unable to firmly establish that the second macropore network is bicontinuous throughout the entire sample volume.
Ventilator-associated pneumonias (VAPs) are a worldwide problem that significantly increases patient morbidity, mortality, and length of stay (LoS), and their effects should be estimated to account for the timing of infection. The purpose of the study was to estimate extra LoS and mortality in an intensive-care unit (ICU) due to a VAP in a cohort of 69 248 admissions followed for 283 069 days in ICUs from 10 countries. Data were arranged according to the multi-state format. Extra LoS and increased risk of death were estimated independently in each country, and their results were combined using a random-effects meta-analysis. VAP prolonged LoS by an average of 2·03 days (95% CI 1·52–2·54 days), and increased the risk of death by 14% (95% CI 2–27). The increased risk of death due to VAP was explained by confounding with patient morbidity.
To estimate the excess length of stay in an intensive care unit (ICU) due to a central line-associated bloodstream infection (CLABSI), using a multistate model that accounts for the timing of infection.
A cohort of 3,560 patients followed up for 36,806 days in ICUs.
Eleven ICUs in 3 Latin American countries: Argentina, Brazil, and Mexico.
All patients admitted to the ICU during a defined time period with a central line in place for more than 24 hours.
The average excess length of stay due to a CLABSI increased in 10 of 11 ICUs and varied from -1.23 days to 4.69 days. A reduction in length of stay in Mexico was probably caused by an increased risk of death due to CLABSI, leading to shorter times to death. Adjusting for patient age and Average Severity of Illness Score tended to increase the estimated excess length of stays due to CLABSI.
CLABSIs are associated with an excess length of ICU stay. The average excess length of stay varies between ICUs, most likely because of the case-mix of admissions and differences in the ways that hospitals deal with infections.
This work reports for the first time the synthesis of γ-(Al1-xFex)2O3 solid solutions with a high specific surface area (200-230 m2/g) by the decomposition of metal oxinate [(Al1-xFex)(C9H6ON)3] and investigated the potential of these materials as catalysts for the synthesis of carbon nanotubes by catalytic chemical vapor deposition using methane or ethylene as carbon the source. The nanocomposite powders prepared by reduction in H2-CH4 contain carbon nanotubes (CNTs), which are mostly double-walled but also contain a fair amount of undesirable carbon nanofibers, hollow carbon particles, and metal particles covered by carbon layers. Moreover, abundant metallic particles are observed to cover the surfaces of the matrix grains. By contrast, the nanocomposite powders prepared by reduction in N2-C2H4 are not fully reduced, and the CNTs are much more abundant and homogeneous. However, they are multiwalled CNTs with a significant proportion of defects. The powders were studied by several techniques including Mössbauer spectroscopy and electron microscopy.
Weathered soil material derived from tectonically emplaced serpentinized ultrabasic intrusive rocks of southern Cameroon has received considerable attention from mining companies due to its extractable-metal (i.e. Ni, Co) potential. As these cations can be incorporated into Fe oxides, it was deemed appropriate to study the mineralogical assemblage of a highly weathered serpentinite soil profile from the area. This study focuses on the different Fe-oxide phases, which were investigated using 57Fe Mössbauer spectroscopy, showing goethite and hematite as the dominant Fe oxides throughout the weathering profile. These minerals, in association with gibbsite and kaolinite, indicate an advanced degree of weathering. The clay fraction of the ‘Lower Limonite’ layer, above the saprolite and at a depth of 7 m, is very rich in goethite, whereas hematite and magnetite are almost absent. Above this layer, the hematite content in the fine-earth and clay fractions increases upwards, while the goethite content remains constant. The significant substitution and change in the particle size of the goethite and the poor crystallinity of hematite, as indicated by the hyperfine parameters and XRD, suggest that the upper material evolved under different pedological conditions compared to the deeper layers. The mixed composition of the upper layers (above 7 m), which contain muscovite and a relatively chaotic distribution of trace elements, suggests ancient mica-schist capping and possibly different cycles of erosion and pedimentation.
The outlook for patients with hypoplastic left heart syndrome has dramatically improved over the past two decades. Universally fatal only 25 years ago, since that time outcomes for staged palliation have shown consistent improvement. Recent reports show that eight to nine patients from every ten can now leave the hospital after the Norwood procedure.1 Attrition following the Norwood procedure, nonetheless, remains significant, with from five to fifteen percent of patients dying between the first and second stages of the Norwood sequence.1–4 Only three-quarters of the patients undergoing surgery for hypoplastic left heart syndrome survive after five years, even at the centres reporting the best outcomes for the Norwood procedure.1,5 In addition to the deaths, some patients are unable to progress through the three stages of reconstruction, and may require cardiac transplantation, or have no options for further therapy. There are many causes for these mortalities and morbidities following the Norwood procedure, including elevated pulmonary vascular resistance, cardiac arrhythmias, coronary arterial insufficiency, right ventricular failure, right ventricular volume overload due to shunt-dependent physiology, and tricuspid valvar regurgitation. Many of these factors are interrelated, and may form feedback loops, which serve to propagate their adverse effects on patients with hypoplastic left heart syndrome.
To report the pooled results of seven prevalence surveys of hospital-acquired infections conducted between November 1996 and November 1999, and to use the data to predict the cumulative incidence of hospital-acquired infections in the same patient group.
The summary and modeling of data gathered from the routine surveillance of the point prevalence of hospital-acquired infections.
Auckland District Health Board Hospitals (Auckland DHBH), the largest publicly funded hospital group in New Zealand supplying secondary and tertiary services.
Point-prevalence surveys were conducted including all patients in Auckland DHBH. Standard definitions of hospital-acquired infection were used. The data from the seven surveys were pooled and used in a modeling exercise to predict the cumulative incidence of hospital-acquired infection. An existing method for the conversion of prevalence to cumulative incidence was applied. Results are presented for all patients and stratified by clinical service and site of hospital-acquired infection.
The underlying patterns of hospital-acquired infection by site and service were stable during the seven time periods. The prevalence rate for all patients was 9.5%, with 553 patients identified with one or more hospital-acquired infections from a population of 5,819. The predicted cumulative incidence for all patients was 6.33% (95% confidence interval, 6.20% to 6.46%).
The prevalence and the predicted cumulative incidence are similar to rates reported in the international literature. The validity of the predicted cumulative incidence derived here is not known. If it were accurate, then the application of this method would represent a cost-effective alternative to incidence studies.
This paper presents various aspects, revealed by Mössbauer spectroscopy, of structural and magnetic properties of Al-substituted small-particle soil-related oxides. For goethite we focus on the relations between the hyperfine fields on the one hand, and crystallinity and Al content on the other. It is argued that these relations only provide a rough estimate of the Al content in natural samples. The ferrimagnetic-like behaviour reflected in the external-field Mössbauer spectra (4.2 K, 60 kOe) of certain Al goethites is presented. The spectra obtained for lepidocrocites are not spectacular, but confirmed that up to ∼10 at.% Al can be incorporated in the structure. Three differently-made series of hematites are considered. The Morin transition and spin structures in hematite are very sensitive to crystallinity and Al content, and probably to the presence of structural OH–. Integral low-energy electron Mössbauer spectroscopy on non-substituted samples indicates that the Morin-transition temperature in the surface layers (2 to 5 nm) is not significantly shifted from the bulk value. Measurements in extremely high magnetic fields (140 kOe) have shown that a spin-flip transition is induced in highly-substituted samples which exhibit no Morin transition in zero field. The use of external fields is crucial for the characterization and precise determination of the hyperfine parameters and site occupancies for maghemites, and for phase analyses of magnetic soils.
We describe the growth of high quality AlN and GaN on Si(111) by gas source molecular beam epitaxy (GSMBE) with ammonia (NH3). The initial nucleation (at 1130−1190K) of an AlN monolayer with full substrate coverage resulted in a very rapid transition to two-dimensional (2D) growth mode of AlN. The rapid transition to the 2D growth mode of AlN is essential for the subsequent growth of high quality GaN, and complete elimination of cracking in thick ( > 2 μm) GaN layers. We show, using Raman scattering (RS) and photoluminescence (PL) measurements, that the tensile stress in the GaN is due to thermal expansion mismatch, is below the ultimate strength of breaking of GaN, and produces a sizable shift in the bandgap. We show that the GSMBE AlN and GaN layers grown on Si can be used as a substrate for subsequent deposition of thick AlN and GaN layers by hydride vapor phase epitaxy (HVPE).
We report the results of epitaxial growth experiments on AlxGa1−xN (0≤ x ≤ 1) on Si(111) and sapphire substrates aimed at understanding the origin and elimination of cracking. We describe growth procedures resulting in thick layers of AlxGa1−xN, grown by gas source molecular beam epitaxy with ammonia, that are free of cracks. In GaN layers with the thickness of ∼2.5 µm, we find the background electron concentration of (1-2)×1016 cm−3 and mobility of (800±100) cm2/Vs. In AlxGa1−xN (0.2 < x < 0.6) with the film thickness of 0.5-0.7 µm the electron concentration of (2-3)×1016 cm−3 is obtained. Low background concentrations in GaN allow for formation of p-n junctions by doping with Mg. Light emitting diodes with the peak emission at 380 nm have been demonstrated.
We describe the growth of high quality AlN and GaN on Si(111) by gas source molecular beam epitaxy (GSMBE) with ammonia (NH3). The initial nucleation (at 1130-1190K) of an AlN monolayer with full substrate coverage resulted in a very rapid transition to two-dimensional (2D) growth mode of AlN. The rapid transition to the 2D growth mode of AlN is essential for the subsequent growth of high quality GaN, and complete elimination of cracking in thick ( > 2 μm) GaN layers. We show, using Raman scattering (RS) and photoluminescence (PL) measurements, that the tensile stress in the GaN is due to thermal expansion mismatch, is below the ultimate strength of breaking of GaN, and produces a sizable shift in the bandgap. We show that the GSMBE AlN and GaN layers grown on Si can be used as a substrate for subsequent deposition of thick AlN and GaN layers by hydride vapor phase epitaxy (HVPE).
We describe a new approach to deposition of Parylene N thin films. It utilizes a small scale, sonic speed, Jet Vapor DepositionTM (JVDTM) process technology in place of the conventional larger scale, slow flow, Gorham apparatus. It employs a simple but powerful strategy to promote radical polymerization: exposure of the growing film, during deposition, to a high flux of atomic hydrogen. We believe that H atoms have two effects: they clean oxygen from the substrate, and they promote crosslinking in the Parylene film by abstraction of H atoms from the Parylene ring or side groups. With “H atom assisted JVD” Parylene N deposits and adheres even on warm substrates; it has reduced index of refraction and dielectric constant.