Connecting low- and high-mass star formation: the intermediate-mass protostar IRAS 05373+2349 VLA 2

Until recently, there have been few studies of the protostellar evolution of intermediate-mass (IM) stars, which may bridge the low- and high-mass regimes. This paper aims to investigate whether the properties of an IM protostar within the IRAS 05373+2349 embedded cluster are similar to that of low- and/or high-mass protostars. We carried out Very Large Array as well as Combined Array for Research in Millimeter Astronomy continuum and 12CO(J=1–0) observations, which uncover seven radio continuum sources (VLA 1–7). The spectral index of VLA 2, associated with the IM protostar is consistent with an ionized stellar wind or jet. The source VLA 3 is coincident with previously observed H2 emission line objects aligned in the north–south direction (P.A. −20 to −12◦), which may be either an ionized jet emanating from VLA 2 or (shock-)ionized cavity walls in the large-scale outflow from VLA 2. The position angle between VLA 2 and 3 is slightly misaligned with the large-scale outflow we map at ∼5-arcsec resolution in 12CO (P.A. ∼30◦), which in the case of a jet suggests precession. The emission from the mm core associated with VLA 2 is also detected; we estimate its mass to be 12–23 M , depending on the contribution from ionized gas. Furthermore, the large-scale outflow has properties intermediate between outflows from low- and high-mass young stars. Therefore, we conclude that the IM protostar within IRAS 05373+2349 is phenomenologically as well as quantitatively intermediate between the low- and high-mass domains

Fragmentation and disk formation in high-mass star formation: The ALMA view of G351.77-0.54 at 0.06" resolution

Aims: We resolve the small-scale structure around the high-mass hot core region G351.77-0.54 to investigate its disk and fragmentation properties. Methods: Using ALMA at 690GHz with baselines exceeding 1.5km, we study the dense gas, dust and outflow emission at an unprecedented spatial resolution of 0.06" ([email protected]). Results: Within the inner few 1000AU, G351.77 fragments into at least four cores (brightness temperatures between 58 and 197K). The central structure around the main submm source #1 with a diameter of ~0.5" does not show additional fragmentation. While the CO(6-5) line wing emission shows an outflow lobe in the north-western direction emanating from source #1, the dense gas tracer CH3CN shows a velocity gradient perpendicular to the outflow that is indicative of rotational motions. Absorption profile measurements against the submm source #2 indicate infall rates on the order of 10^{-4} to 10^{-3}M_sun/yr which can be considered as an upper limit of the mean accretion rates. The position-velocity diagrams are consistent with a central rotating disk-like structure embedded in an infalling envelope, but they may also be influenced by the outflow. Using the CH_3CN(37_k-36_k) k-ladder with excitation temperatures up to 1300K, we derive a gas temperature map of source #1 exhibiting temperatures often in excess of 1000K. Brightness temperatures of the submm continuum never exceed 200K. This discrepancy between gas temperatures and submm dust brightness temperatures (in the optically thick limit) indicates that the dust may trace the disk mid-plane whereas the gas could be tracing a hotter gaseous disk surface layer. In addition, we conduct a pixel-by-pixel Toomre gravitational stability analysis of the central rotating structure. The derived high Q values throughout the structure confirm that this central region appears stable against gravitational instability

Spiral arms and instability within the AFGL 4176 mm1 disc

We present high-resolution (30 mas or 130 au at 4.2 kpc) Atacama Large Millimeter/submillimeter Array observations at 1.2 mm of the disc around the forming O-type star AFGL 4176 mm1. The disc (AFGL 4176 mm1-main) has a radius of ∼1000 au and contains significant structure, most notably a spiral arm on its redshifted side. We fitted the observed spiral with logarithmic and Archimedean spiral models. We find that both models can describe its structure, but the Archimedean spiral with a varying pitch angle fits its morphology marginally better. As well as signatures of rotation across the disc, we observe gas arcs in CH3CN that connect to other millimetre continuum sources in the field, supporting the picture of interactions within a small cluster around AFGL 4176 mm1-main. Using local thermodynamic equilibrium modelling of the CH3CN K-ladder, we determine the temperature and velocity field across the disc, and thus produce a map of the Toomre stability parameter. Our results indicate that the outer disc is gravitationally unstable and has already fragmented or is likely to fragment in the future, possibly producing further companions. These observations provide evidence that disc fragmentation is one possible pathway towards explaining the high fraction of multiple systems around high-mass stars

Using psychological theory to understand the clinical management of type 2 diabetes in Primary Care : a comparison across two European countries

Peer reviewedPublisher PD

Forming spectroscopic massive proto-binaries by disk fragmentation

The surroundings of massive protostars constitute an accretion disc which has numerically been shown to be subject to fragmentation and responsible for luminous accretion-driven outbursts. Moreover, it is suspected to produce close binary companions which will later strongly influence the star's future evolution in the Hertzsprung–Russel diagram. We present three-dimensional gravitation-radiation-hydrodynamic numerical simulations of 100 M⊙ pre-stellar cores. We find that accretion discs of young massive stars violently fragment without preventing the (highly variable) accretion of gaseous clumps on to the protostars. While acquiring the characteristics of a nascent low-mass companion, some disc fragments migrate on to the central massive protostar with dynamical properties showing that its final Keplerian orbit is close enough to constitute a close massive protobinary system, having a young high- and a low-mass components. We conclude on the viability of the disc fragmentation channel for the formation of such short-period binaries, and that both processes – close massive binary formation and accretion bursts – may happen at the same time. FU-Orionis-type bursts, such as observed in the young high-mass star S255IR−NIRS3, may not only indicate ongoing disc fragmentation, but also be considered as a tracer for the formation of close massive binaries – progenitors of the subsequent massive spectroscopic binaries – once the high-mass component of the system will enter the main-sequence phase of its evolution. Finally, we investigate the Atacama Large (sub-)Millimeter Array observability of the disc fragments

A search for non-thermal radio emission from jets of massive young stellar objects

Massive young stellar objects (MYSOs) have recently been shown to drive jets whose particles can interact with either the magnetic fields of the jet or ambient medium to emit non-thermal radiation. We report a search for non-thermal radio emission from a sample of 15 MYSOs to establish the prevalence of the emission in the objects. We used their spectra across the L, C, and Q bands along with spectral index maps to characterize their emission. We find that about 50 per cent of the sources show evidence for non-thermal emission with 40 per cent showing clear non-thermal lobes, especially sources of higher bolometric luminosity. The common or IRAS names of the sources that manifest non-thermal lobes are V645Cyg, IRAS 22134+5834, NGC 7538 IRS 9, IRAS 23262 + 640, AFGL 402d, and AFGL 490. All the central cores of the sources are thermal with corresponding mass-loss rates that lie in the range of ∼3 × 10−7 to 7×10−6M⊙yr−1⁠. Given the presence of non-thermal lobes in some of the sources and the evidence of non-thermal emission from some spectral index maps, it seems that magnetic fields play a significant role in the jets of massive protostars. Also noted is that some of the sources show evidence of binarity and variability

The development of a theory-based intervention to promote appropriate disclosure of a diagnosis of dementia

Background: The development and description of interventions to change professional practice are often limited by the lack of an explicit theoretical and empirical basis. We set out to develop an intervention to promote appropriate disclosure of a diagnosis of dementia based on theoretical and empirical work. Methods: We identified three key disclosure behaviours: finding out what the patient already knows or suspects about their diagnosis; using the actual words 'dementia' or 'Alzheimer's disease' when talking to the patient; and exploring what the diagnosis means to the patient. We conducted a questionnaire survey of older peoples' mental health teams (MHTs) based upon theoretical constructs from the Theory of Planned Behaviour (TPB) and Social Cognitive Theory (SCT) and used the findings to identify factors that predicted mental health professionals' intentions to perform each behaviour. We selected behaviour change techniques likely to alter these factors. Results: The change techniques selected were: persuasive communication to target subjective norm; behavioural modelling and graded tasks to target self-efficacy; persuasive communication to target attitude towards the use of explicit terminology when talking to the patient; and behavioural modelling by MHTs to target perceived behavioural control for finding out what the patient already knows or suspects and exploring what the diagnosis means to the patient. We operationalised these behaviour change techniques using an interactive 'pen and paper' intervention designed to increase intentions to perform the three target behaviours. Conclusion : It is feasible to develop an intervention to change professional behaviour based upon theoretical models, empirical data and evidence based behaviour change techniques. The next step is to evaluate the effect of such an intervention on behavioural intention. We argue that this approach to development and reporting of interventions will contribute to the science of implementation by providing replicable interventions that illuminate the principles and processes underlying change.This project is funded by UK Medical Research Council, Grant reference number G0300999. Jeremy Grimshaw holds a Canada Research Chair in Health Knowledge Transfer and Uptake. Jill Francis is funded by the Chief Scientist Office of the Scottish Government Health Directorate. The views expressed in this study are those of the authors

Explaining the effects of an intervention designed to promote evidence-based diabetes care : a theory-based process evaluation of a pragmatic cluster randomised controlled trial

Background The results of randomised controlled trials can be usefully illuminated by studies of the processes by which they achieve their effects. The Theory of Planned Behaviour (TPB) offers a framework for conducting such studies. This study used TPB to explore the observed effects in a pragmatic cluster randomised controlled trial of a structured recall and prompting intervention to increase evidence-based diabetes care that was conducted in three Primary Care Trusts in England. Methods All general practitioners and nurses in practices involved in the trial were sent a postal questionnaire at the end of the intervention period, based on the TPB (predictor variables: attitude; subjective norm; perceived behavioural control, or PBC). It focussed on three clinical behaviours recommended in diabetes care: measuring blood pressure; inspecting feet; and prescribing statins. Multivariate analyses of variance and multiple regression analyses were used to explore changes in cognitions and thereby better understand trial effects. Results Fifty-nine general medical practitioners and 53 practice nurses (intervention: n = 55, 41.98% of trial participants; control: n = 57, 38.26% of trial participants) completed the questionnaire. There were no differences between groups in mean scores for attitudes, subjective norms, PBC or intentions. Control group clinicians had 'normatively-driven' intentions (i.e., related to subjective norm scores), whereas intervention group clinicians had 'attitudinally-driven' intentions (i.e., related to attitude scores) for foot inspection and statin prescription. After controlling for effects of the three predictor variables, this group difference was significant for foot inspection behaviour (trial group × attitude interaction, beta = 0.72, p < 0.05; trial group × subjective norm interaction, beta = -0.65, p < 0.05). Conclusion Attitudinally-driven intentions are proposed to be more consistently translated into action than normatively-driven intentions. This proposition was supported by the findings, thus offering an interpretation of the trial effects. This analytic approach demonstrates the potential of the TPB to explain trial effects in terms of different relationships between variables rather than differences in mean scores. This study illustrates the use of theory-based process evaluation to uncover processes underlying change in implementation trials.European Union ReBEQI projec

A Detailed View of the Circumstellar Environment and Disk of the Forming O-star AFGL 4176

We present a detailed analysis of the disk and circumstellar environment of the forming O-type star AFGL 4176 mm1, placing results from the Atacama Large Millimeter/submillimeter Array (ALMA) into context with multiwavelength data. With ALMA, we detect seventeen 1.2 mm continuum sources within 5'' (21,000 au) of AFGL 4176 mm1. We find that mm1 has a spectral index of 3.4 ± 0.2 across the ALMA band, with >87% of its 1.2 mm continuum emission from dust. The source mm2, projected 4200 au from mm1, may be a companion or a blueshifted knot in a jet. We also explore the morphological differences between the molecular lines detected with ALMA, finding 203 lines from 25 molecules, which we categorize into several morphological types. Our results show that AFGL 4176 mm1 provides an example of a forming O-star with a large and chemically complex disk, which is mainly traced by nitrogen-bearing molecules. Lines that show strong emission on the blueshifted side of the disk are predominantly oxygen-bearing, which we suggest are tracing a disk accretion shock. The molecules C34S, H2CS, and CH3CCN trace a slow wide-angle wind or dense structures in the outflow cavity walls. With the Australia Telescope Compact Array (ATCA), we detect a compact continuum source (96% is from ionized gas. The ATCA NH3(1, 1) and (2, 2) emission traces a large-scale (r ~ 0.5 pc) rotating toroid with the disk source mm1 in the blueshifted part of this structure offset to the northwest

Developing the content of two behavioural interventions : using theory-based interventions to promote GP management of upper respiratory tract infection without prescribing antibiotics #1

Background: Evidence shows that antibiotics have limited effectiveness in the management of upper respiratory tract infection (URTI) yet GPs continue to prescribe antibiotics. Implementation research does not currently provide a strong evidence base to guide the choice of interventions to promote the uptake of such evidence-based practice by health professionals. While systematic reviews demonstrate that interventions to change clinical practice can be effective, heterogeneity between studies hinders generalisation to routine practice. Psychological models of behaviour change that have been used successfully to predict variation in behaviour in the general population can also predict the clinical behaviour of healthcare professionals. The purpose of this study was to design two theoretically-based interventions to promote the management of upper respiratory tract infection (URTI) without prescribing antibiotics. Method: Interventions were developed using a systematic, empirically informed approach in which we: selected theoretical frameworks; identified modifiable behavioural antecedents that predicted GPs intended and actual management of URTI; mapped these target antecedents on to evidence-based behaviour change techniques; and operationalised intervention components in a format suitable for delivery by postal questionnaire. Results: We identified two psychological constructs that predicted GP management of URTI: "Self-efficacy," representing belief in one's capabilities, and "Anticipated consequences," representing beliefs about the consequences of one's actions. Behavioural techniques known to be effective in changing these beliefs were used in the design of two paper-based, interactive interventions. Intervention 1 targeted self-efficacy and required GPs to consider progressively more difficult situations in a "graded task" and to develop an "action plan" of what to do when next presented with one of these situations. Intervention 2 targeted anticipated consequences and required GPs to respond to a "persuasive communication" containing a series of pictures representing the consequences of managing URTI with and without antibiotics. Conclusion: It is feasible to systematically develop theoretically-based interventions to change professional practice. Two interventions were designed that differentially target generalisable constructs predictive of GP management of URTI. Our detailed and scientific rationale for the choice and design of our interventions will provide a basis for understanding any effects identified in their evaluation. Trial registration: Clinicaltrials.gov NCT00376142This study is funded by the European Commission Research Directorate as part of a multi-partner program: Research Based Education and Quality Improvement (ReBEQI): A Framework and tools to develop effective quality improvement programs in European healthcare. (Proposal No: QLRT-2001-00657)