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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.
Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350 $\mu$m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200 $\mu$m images will also have a factor $\sim $30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
The SPICA mid- and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimised detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging, and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular, (i) the access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star-formation rates within and between galaxies, (ii) observations of HD rotational lines (out to ~10 Mpc) and fine structure lines such as [C ii] 158 μm (out to ~100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit, (iii) far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies, (iv) observations of far-infrared cooling lines such as [O i] 63 μm from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
Our current knowledge of star formation and accretion luminosity at high redshift (z > 3–4), as well as the possible connections between them, relies mostly on observations in the rest-frame ultraviolet, which are strongly affected by dust obscuration. Due to the lack of sensitivity of past and current infrared instrumentation, so far it has not been possible to get a glimpse into the early phases of the dust-obscured Universe. Among the next generation of infrared observatories, SPICA, observing in the 12–350 µm range, will be the only facility that can enable us to trace the evolution of the obscured star-formation rate and black-hole accretion rate densities over cosmic time, from the peak of their activity back to the reionisation epoch (i.e., 3 < z ≲ 6–7), where its predecessors had severe limitations. Here, we discuss the potential of photometric surveys performed with the SPICA mid-infrared instrument, enabled by the very low level of impact of dust obscuration in a band centred at 34 µm. These unique unbiased photometric surveys that SPICA will perform will fully characterise the evolution of AGNs and star-forming galaxies after reionisation.
The physical processes driving the chemical evolution of galaxies in the last ~ 11Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of the star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared observatory like SPICA, will be sensitive enough to peer through the dust-obscured regions of galaxies and access the rest-frame mid- to far-infrared range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ~ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed.
Much can be learned from terrestrial planets that appear to have had the potential to be habitable, but failed to realize that potential. Mars shows evidence of a once hospitable surface environment. The reasons for its current state, and in particular its thin atmosphere and dry surface, are of great interest for what they can tell us about habitable zone planet outcomes. A main goal of the MAVEN mission is to observe Mars’ atmosphere responses to solar and space weather influences, and in particular atmosphere escape related to space weather ‘storms’ caused by interplanetary coronal mass ejections (ICMEs). Numerical experiments with a data-validated MHD model suggest how the effects of an observed moderately strong ICME compare to what happens during a more extreme event. The results suggest the kinds of solar and space weather conditions that can have evolutionary importance at a planet like Mars.
We present results of Herschel PACS imaging spectroscopy data toward ten massive young stellar objects taken as part of the WISH project. Our sample consists of four high mass protostellar objects (HMPOs), two hot molecular cores (HMCs), and four ultracompact HII regions (UCHIIs), and the spectra cover a broad range of wavelengths (55 to 210 μm) imaged over an ~50” field with 5×5 spaxels. By fitting the continua utilizing a modified black-body formula we estimate mass-weighted dust temperature and column density distributions of warm dust and find that UCHII regions are hottest and HMCs are most deeply embedded. We also estimate rotational temperature and column density distributions of warm CO gas using the rotational diagram analysis, which are comparable over targets in contrast to continuum results. By comparing high J CO line fluxes to the RATRAN estimates of centrally heated envelope models, we find that majority of warm CO originates from bipolar outflow shocks.
Salt-marsh sediments provide accurate and precise reconstructions of late Holocene relative sea-level changes. However, compaction of salt-marsh stratigraphies can cause post-depositional lowering (PDL) of the samples used to reconstruct sea level, creating an estimation of former sea level that is too low and a rate of rise that is too great. We estimated the contribution of compaction to late Holocene sea-level trends reconstructed at Tump Point, North Carolina, USA. We used a geotechnical model that was empirically calibrated by performing tests on surface sediments from modern depositional environments analogous to those encountered in the sediment core. The model generated depth-specific estimates of PDL, allowing samples to be returned to their depositional altitudes. After removing an estimate of land-level change, error-in-variables changepoint analysis of the decompacted and original sea-level reconstructions identified three trends. Compaction did not generate artificial sea-level trends and cannot be invoked as a causal mechanism for the features in the Tump Point record. The maximum relative contribution of compaction to reconstructed sea-level change was 12%. The decompacted sea-level record shows 1.71 mm yr− 1 of rise since AD 1845.
Star formation is evolving very fast in the second half of the Universe, and it is as yet unclear whether this is due to evolving gas content, or evolving star formation efficiency (SFE). We have carried out a survey of ultra-luminous galaxies (ULIRG) between z = 0.2 and 1, to check the gas fraction in this domain of redshift which is still poorly known. Our survey with the IRAM-30m detected 33 galaxies out of 69, and we derive a significant evolution of both the gas fraction and SFE of ULIRGs over the whole period, and in particular a turning point around z = 0.35. The result is sensitive to the CO-to-H2 conversion factor adopted, and both gas fraction and SFE have comparable evolution, when we adopt the low starburst conversion factor of α = 0.8 M⊙ (K km s−1 pc2)−1. Adopting a higher α will increase the role of the gas fraction. Using α = 0.8, the SFE and the gas fraction for z∼0.2-1.0 ULIRGs are found to be significantly higher, by a factor 3, than for local ULIRGs, and are comparable to high redshift ones. We compare this evolution to the expected cosmic H2 abundance and the cosmic star formation history.
Star-formation is one of the main processes that shape galaxies, and together with black-hole accretion activity the two agents of energy production in galaxies. It is important on a range of scales from star clusters/OB associations to galaxy-wide and even group/cluster scales. Recently, studies of star-formation in sub-galactic and galaxy-wide scales have met significant advances owing to: (a) developments in the theory of stellar evolution, stellar atmospheres, and radiative transfer in the interstellar medium; (b) the availability of more sensitive and higher resolution data; and (c) observations in previously poorly charted wavebands (e.g. Ultraviolet, Infrared, and X-rays). These data allow us to study more galaxies at ever-increasing distances and nearby galaxies in greater detail, and different modes of star formation activity such as massive star formation and low level continuous star formation in a variety of environments. In this contribution we summarize recent results in the fields of multi-wavelength calibrations of star-formation rate indicators, the Stellar Initial Mass function, and radiative transfer and modeling of the Spectrale Energy Disrtributions of galaxies.
Within the key project “Herschel M 33 extended survey” (HerM33es), we are studying the physical and chemical processes driving star formation and galactic evolution in the nearby galaxy M 33, combining the study of local conditions affecting individual star formation with properties only becoming apparent on global scales. Here, we present recent results obtained by the HerM33es team. Combining Spitzer and Herschel data ranging from 3.6 μm to 500μm, along with H i, Hα, and GALEX UV data, we have studied the dust at high spatial resolutions of 150 pc, providing estimators of the total infrared (TIR) brightness and of the star formation rate. While the temperature of the warm dust at high brightness is driven by young massive stars, evolved stellar populations appear to drive the temperature of the cold dust. Plane-parallel models of photon dominated regions (PDRs) fail to reproduce fully the [C ii], [O i], and CO maps obtained in a first spectroscopic study of one 2′ × 2′ subregion of M 33, located on the inner, northern spiral arm and encompassing the H ii region BCLMP 302.
We present results from the Herschel and IRAM projects to map M33 in the dust continuum and main emission lines, particularly C[II] and CO. The temperature of the cool dust decreases with distance from the center of M33 from ~25K to ~13K. The CO emission generally follows the dust temperature and the overall dust emission. However, about 1/6 of the molecular clouds are not associated with massive stars, such that about 1/6th the lifetime of an entity identifiable as a molecular cloud is in a pre-star formation state. These clouds are less CO-bright than those with massive stars. The largest sample of molecular clouds currently available for an external galaxy shows that the cloud CO luminosity function, usually viewed as the cloud H2 mass, steepens with radius such that smaller clouds are more numerous in the outer parts. The observations of the C[II] line with Herschel indicate that the C[II] emission traces on-going star formation rather than the neutral gas. This identification will be tested via velocity-resolved Herschel/HIFI C[II] spectra in the near future.
The radioimmunoassay for brucellosis previously reported from this laboratory was a sensitive and useful method for detecting antibody against Brucella abortus in bovine serum. Changes in the procedure have improved sensitivity, have apparently increased interassay precision, and have made the assay easier to perform.
The role of viruses and M. pneumoniae in episodes of acute respiratory illness in childhood has been studied in a London general practice. The total isolation rate was 31·7%, but the rate varied from 32·6% in upper respiratory infections to 64·0% in pneumonia. The clinical features associated with infection were influenced not only by the type of agent but also by age and other host factors in the infected children. Rhinoviruses were more commonly isolated than any other agent and were frequently associated with wheezy bronchitis.
Objectives: To review all cases of atrioventricular septal defects in Northern Ireland from January 1990 to February 1999, examining clinical and morphological features, management, and outcome. Methods: A retrospective case note analysis of 106 subjects with comparisons between subgroups. Results: An atrioventricular septal defect was part of a more complex abnormality in 50 of the patients (47%). Down's syndrome was present in 57 (54%). Cardiac surgery was performed in 81%. The defects were unrestrictive in 69 patients (65%), 45 of whom had Down's syndrome. Complex associated abnormalities existed in 36 patients, and 10 of these died without cardiac surgery. Operative mortality was 9.5% for those with co-existing Down's syndrome group, and 14.3% for the chromosomally normal patients. The ventricular components of the septal defect were restrictive in 23 patients (22%), with 9 having Down's syndrome. Spontaneous closure occurred in more than half of these patients. Mortality was zero. The septal defect was exclusively at atrial level in 14 patients (“primum” defects – 13%), and 3 of these had Down's syndrome. Operative mortality was again zero. Median duration of postoperative follow-up was 3 and a half years. Overall, moderate to severe left atrioventricular valvar regurgitation was observed postoperatively in 23% at follow-up. Conclusions: Mortality was highest in the atrioventricular septal defects with an unrestrictive ventricular component. Uncomplicated cases had good outcomes. Patients without Down's syndrome tended to have more associated cardiac abnormalities, and to have more postoperative arrhythmias. Approximately half of the defects with restrictive ventricular components closed spontaneously. Moderate postoperative left atrioventricular valvar regurgitation was commonest in patients with the defect exclusively at atrial level.
We investigate the process of galaxy formation as can be observed in the only currently forming galaxies - the so-called Tidal Dwarf Galaxies, hereafter TDGs - through observations of the molecular gas detected via its CO (Carbon Monoxide) emission. Molecular gas is a key element in the galaxy formation process, providing the link between a cloud of gas and a bona fide galaxy. We have now detected CO in 9 TDGs with an overall detection rate of 80%, showing that molecular gas is abundant in TDGs, up to a few 108M⊙. The CO emission coincides both spatially and kinematically with the HI emission, indicating that the molecular gas forms from the atomic hydrogen where the HI column density is high. A possible trend of more evolved TDGs having greater molecular gas masses is observed, in accord with the transformation of HI into H2. Although uncertainties are still large for individual objects as the geometry is unknown, we find that the “dynamical” masses of TDGs, estimated from the CO line widths, do not seem to be greater than the “visible” masses (HI + H2 + a stellar component), i.e., TDGs require no dark matter. We provide evidence that TDGs are self-gravitating entities, implying that we are witnessing the ensemble of processes in galaxy formation: concentration of large amounts of gas in a bound object, condensation of the gas, which is atomic at this point, to form molecular gas and the subsequent star formation from the dense molecular component.
Schistosomiasis is initiated when cercarial larvae invade human skin. Contrary to long-held assumptions, most cercariae of Schistosoma mansoni do not shed their propulsive tails as they penetrate. Scanning electron microscopy studies and infection experiments with entire human skin and differentiated, stratum corneum-like, human keratinocyte cultures, have shown that most cercarial tails enter the skin along with their bodies. We propose that this behaviour is an adaptive trait linked with concomitant immunity.