11 research outputs found
ALMA observations of the Extended Green Object G19.010.03: II. A massive protostar with typical chemical abundances surrounded by four low-mass prestellar core candidates
We present a study of the physical and chemical properties of the Extended
Green Object (EGO) G19.010.03 using sub-arcsecond angular resolution Atacama
Large Millimeter/submillimeter Array (ALMA) 1.05mm and Karl G. Jansky Very
Large Array (VLA) 1.21cm data. G19.010.03 MM1, the millimetre source
associated with the central massive young stellar object (MYSO), appeared
isolated and potentially chemically young in previous Submillimeter Array
observations. In our -resolution ALMA data, MM1 has four low-mass
millimetre companions within 0.12pc, all lacking maser or outflow emission,
indicating they may be prestellar cores. With a rich ALMA spectrum full of
complex organic molecules, MM1 does not appear chemically young, but has
molecular abundances typical of high-mass hot cores in the literature. At the
1.05mm continuum peak of MM1,
cm
and K based on pixel-by-pixel
Bayesian analysis of LTE synthetic methanol spectra across MM1. Intriguingly,
the peak CHOH K is offset from MM1's
millimetre continuum peak by au, and a region of elevated
CHOH coincides with free-free VLA 5.01cm continuum,
adding to the tentative evidence for a possible unresolved high-mass binary in
MM1. In our VLA 1.21cm data, we report the first NH(3,3) maser detections
towards G19.010.03, along with candidate 25GHz CHOH
maser emission; both are spatially and kinematically coincident with 44GHz
Class I CHOH masers in the MM1 outflow. We also report the ALMA detection
of candidate 278.3GHz Class I CHOH maser emission towards this outflow,
strengthening the connection of these three maser types to MYSO outflows.Comment: 24 pages, 15 figures, 7 tables, Accepted for publication in MNRA
ALMA observations of the Extended Green Object G19.01-0.03 : II. A massive protostar with typical chemical abundances surrounded by four low-mass prestellar core candidates
Funding: GMW acknowledges support from the UK’s Science and Technology Facilities Council (STFC) under ST/W00125X/1. CJC acknowledges support from the UK’s STFC under ST/M001296/1. PN acknowledges support by grant 618.000.001 from the Dutch Research Council (NWO) and support by the Danish National Research Foundation through the Center of Excellence "InterCat" (Grant agreement no.: DNRF150).We present a study of the physical and chemical properties of the Extended Green Object (EGO) G19.01−0.03 using sub-arcsecond angular resolution Atacama Large Millimeter/submillimeter Array (ALMA) 1.05 mm and Karl G. Jansky Very Large Array (VLA) 1.21 cm data. G19.01−0.03 MM1, the millimetre source associated with the central massive young stellar object (MYSO), appeared isolated and potentially chemically young in previous Submillimeter Array observations. In our ∼0.4″-resolution ALMA data, MM1 has four low-mass millimetre companions within 0.12 pc, all lacking maser or outflow emission, indicating they may be prestellar cores. With a rich ALMA spectrum full of complex organic molecules, MM1 does not appear chemically young, but has molecular abundances typical of high-mass hot cores in the literature. At the 1.05 mm continuum peak of MM1, N(CH3OH) = (2.22 ± 0.01) × 1018 cm−2 and Tex=162.7+0.3−0.5 K based on pixel-by-pixel Bayesian analysis of LTE synthetic methanol spectra across MM1. Intriguingly, the peak CH3OH Tex = 165.5 ± 0.6 K is offset from MM1’s millimetre continuum peak by 0.22″ ∼ 880 AU, and a region of elevated CH3OH Tex coincides with free-free VLA 5.01 cm continuum, adding to the tentative evidence for a possible unresolved high-mass binary in MM1. In our VLA 1.21 cm data, we report the first NH3(3,3) maser detections towards G19.01−0.03, along with candidate 25 GHz CH3OH 5(2, 3) − 5(1, 4) maser emission; both are spatially and kinematically coincident with 44 GHz Class I CH3OH masers in the MM1 outflow. We also report the ALMA detection of candidate 278.3 GHz Class I CH3OH maser emission towards this outflow, strengthening the connection of these three maser types to MYSO outflows.Publisher PDFPeer reviewe
Extending the authority for sickness certification beyond the medical profession: the importance of 'boundary work'
The study aimed to explore the views of general practitioners (GPs), nurses and physiotherapists towards extending the role of sickness certification beyond the medical profession in primary care
Gravity drives the evolution of infrared dark hubs:JVLA observations of SDC13
Converging networks of interstellar filaments i.e. hubs, have been recently
linked to the formation of stellar clusters and massive stars. The goal is to
study the kinematic and density structure of the SDC13 hub at high angular
resolution to determine what drives its evolution and fragmentation. We have
mapped SDC13, a 1000Msun infrared dark hub, in NH3(1,1) and NH3(2,2) emission
lines, with both the JVLA and GBT down to 0.07pc. The mass-per-unit-lengths of
all four hub filaments are thermally super-critical, consistent with the
presence of tens of gravitationally bound cores along them. These cores exhibit
regular separation of 0.37 +/- 0.16 pc suggesting gravitational instabilities
running along these super-critical filaments are responsible for their
fragmentation. The observed local increase of the dense gas velocity dispersion
towards starless cores is believed to be a consequence of such fragmentation
process. We see velocity gradient peaks towards 63% of the cores as expected
during the early stages of filament fragmentation. The most massive cores are
located at the filament junctions, where the velocity dispersion is the
largest. We interpret this as the result of the hub morphology generating the
largest acceleration gradients near the hub centre. We propose a scenario for
the evolution of the SDC13 hub in which filaments first form as post-shock
structures in a supersonic turbulent flow. Then gravity takes over and starts
shaping the evolution of the hub, both fragmenting filaments and pulling the
gas towards the centre of the gravitational well. By doing so, gravitational
energy is converted into kinetic energy in both local (cores) and global (hub
centre) potential well minima. Furthermore, the generation of larger
gravitational acceleration gradients at the filament junctions promotes the
formation of more massive cores. [abridged]Comment: 25 pages, 26 figures, 3 tables, abridged abstract, Accepted for
publication in A&
Associations between Gastrointestinal Nematode Infection Burden and Lying Behaviour as Measured by Accelerometers in Periparturient Ewes
The application of precision livestock farming (PLF) technologies will underpin new strategies to support the control of livestock disease. However, PLF technology is underexploited within the sheep industry compared to other livestock sectors, and research is essential to identify opportunities for PLF applications. These opportunities include the control of endemic sheep disease such as parasitic gastroenteritis, caused by gastrointestinal nematode infections, which is estimated to cost the European sheep industry EUR 120 million annually. In this study, tri-axial accelerometers recorded the behaviour of 54 periparturient Welsh Mule ewes to discover if gastrointestinal nematode (GIN) infection burden, as measured by faecal egg count (FEC), was associated with behavioural variation. Linear mixed models identified that increasing FECs in periparturient ewes were significantly associated with a greater number of lying bouts per day and lower bout durations (p = 0.013 and p = 0.010, respectively). The results demonstrate that FECs of housed periparturient ewes are associated with detectable variations in ewe behaviour, and as such, with further investigation there is potential to develop future targeted selective treatment protocols against GIN in sheep based on behaviour as measured by PLF technologies
Mapping the extended frontiers of escapism: binge-watching and hyperdiegetic exploration
Formation of the SDC13 Hub-Filament System: A Cloud-Cloud Collision Imprinted on The Multiscale Magnetic Field
Hub-filament systems (HFSs) are potential sites of protocluster and massive
star formation, and play a key role in mass accumulation. We report JCMT POL-2
850 m polarization observations toward the massive HFS SDC13. We detect an
organized magnetic field near the hub center with a cloud-scale "U-shape"
morphology following the western edge of the hub. Together with larger-scale
APEX 13CO and PLANCK polarization data, we find that SDC13 is located at the
convergent point of three giant molecular clouds (GMCs) along a large-scale,
partially spiral-like magnetic field. The smaller "U-shape" magnetic field is
perpendicular to the large-scale magnetic field and the converging GMCs. We
explain this as the result of a cloud-cloud collision. Within SDC13, we find
that local gravity and velocity gradients point toward filament ridges and hub
center. This suggests that gas can locally be pulled onto filaments and overall
converges to the hub center. A virial analysis of the central hub shows that
gravity dominates magnetic and kinematic energy. Combining large- and
small-scale analyses, we propose that SDC13 is initially formed from a
collision of clouds moving along the large-scale magnetic field. In the
post-shock regions, after the initial turbulent energy has dissipated, gravity
takes over and starts to drive the gas accretion along the filaments toward the
hub center.Comment: 34 pages, 25 figures, 3 table
The Australian Broadcasting Corporation’s multiplatform projects : industrial logics of children’s content provision in the digital television era
This paper traces the development of children’s multiplatform commissioning at the Australian Broadcasting Corporation (ABC) in the context of the digitalisation of Australian television. Whilst recent scholarship has focussed on ‘post-broadcast’ or ‘second-shift’ industrial practices, designed to engage view(s)ers with proprietary media brands, less attention has been focussed on children’s and young adults’ television in a public service context. Further, although multiplatform projects in the United States and Britain have been the subject of considerable analysis, less work has attempted to contextualise cultural production in smaller media markets. The paper explores two recent multiplatform projects through textual analysis, empirical research (consisting of interviews with key industry personnel) and an investigation of recent policy documents. The authors argue that the ABC’s mixed diet of children’s programming, featuring an educative or social developmental agenda, is complemented by its appeals to audience ‘participation’, with the Corporation maintaining public service values alongside the need to expand audience reach and the legitimacy of its brand. It finds that the ABC’s historical platform infrastructure, across radio, television and online, have allowed it to move beyond a market failure model to exploit multiplatform synergies competitively in the distribution of Australian children’s content to audiences on-demand
Whole-genome sequencing reveals host factors underlying critical COVID-19
Altres ajuts: Department of Health and Social Care (DHSC); Illumina; LifeArc; Medical Research Council (MRC); UKRI; Sepsis Research (the Fiona Elizabeth Agnew Trust); the Intensive Care Society, Wellcome Trust Senior Research Fellowship (223164/Z/21/Z); BBSRC Institute Program Support Grant to the Roslin Institute (BBS/E/D/20002172, BBS/E/D/10002070, BBS/E/D/30002275); UKRI grants (MC_PC_20004, MC_PC_19025, MC_PC_1905, MRNO2995X/1); UK Research and Innovation (MC_PC_20029); the Wellcome PhD training fellowship for clinicians (204979/Z/16/Z); the Edinburgh Clinical Academic Track (ECAT) programme; the National Institute for Health Research, the Wellcome Trust; the MRC; Cancer Research UK; the DHSC; NHS England; the Smilow family; the National Center for Advancing Translational Sciences of the National Institutes of Health (CTSA award number UL1TR001878); the Perelman School of Medicine at the University of Pennsylvania; National Institute on Aging (NIA U01AG009740); the National Institute on Aging (RC2 AG036495, RC4 AG039029); the Common Fund of the Office of the Director of the National Institutes of Health; NCI; NHGRI; NHLBI; NIDA; NIMH; NINDS.Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care or hospitalization after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes-including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)-in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease