1,493 research outputs found
The Gas Properties of the W3 GMC: A HARP study
We present 12CO, 13CO and C18O J=3-2 maps of the W3 GMC made at the James
Clerk Maxwell Telescope. We combine these observations with Five Colleges Radio
Astronomy Observatory CO J=1-0 data to produce the first map of molecular-gas
temperatures across a GMC and the most accurate determination of the mass
distribution in W3 yet obtained. We measure excitation temperatures in the part
of the cloud dominated by triggered star formation (the High Density Layer,
HDL) of 15-30 K, while in the rest of the cloud, which is relatively unaffected
by triggering (Low Density Layer, LDL), the excitation temperature is generally
less than 12 K. We identify a temperature gradient in the HDL which we
associate with an age sequence in the embedded massive star-forming regions. We
measure the mass of the cloud to be 4.4+/-0.4 x 10^5 solar masses, in agreement
with previous estimates. Existing sub-mm continuum data are used to derive the
fraction of gas mass in dense clumps as a function of position in the cloud.
This fraction, which we interpret as a Clump Formation Efficiency (CFE), is
significantly enhanced across the HDL, probably due to the triggering. Finally,
we measure the 3D rms Mach Number as a function of position and find a
correlation between the Mach number and the CFE within the HDL only. This
correlation is interpreted as due to feedback from the newly-formed stars and a
change in its slope between the three main star-forming regions is construed as
another evolutionary effect. We conclude that triggering has affected the
star-formation process in the W3 GMC primarily by creating additional dense
structures that can collapse into stars. Any traces of changes in CFE due to
additional turbulence have since been overruled by the feedback effects of the
star-forming process itself.Comment: 14 pages, 11 figures, 1 table, accepted for publication in MNRA
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Pathways to inflated responsibility beliefs in adolescent obsessive-compulsive disorder: a preliminary investigation
Background: An inflated sense of responsibility is characteristic of obsessive-compulsive
disorder (OCD). No previous studies have investigated its origins. Five potential pathways to
inflated responsibility beliefs have been proposed; these are tested in this study. Method: A
novel measure, the Origins Questionnaire for Adolescents (OQA), was developed to assess
experiences on these five pathways. Reliability of the OQA was investigated. The experiences
on the five pathways to inflated responsibility beliefs of sixteen adolescents with a history of
OCD were compared to sixteen adolescents with no history of OCD. Parents also reported on
adolescents’ experiences on the five pathways. Results: Inter-rater reliability was high. The
internal consistency of the subscales were only partly satisfactory. The groups differed on one
pathway; the clinical group reported a higher sense of responsibility for significant incidents with
a negative outcome prior to onset of OCD. Conclusions: An inflated sense of responsibility, in
combination with the occurrence of specific incidents, might act as a vulnerability factor for
development of OCD. Future research should consider how to measure the subtle effects of
experiences of responsibility over the course of development
Youth Migration and the Politics of Wellbeing: Stories of Life in Transition
Drawing on accounts of unaccompanied migrant young people becoming adult, this book offers a political economy analysis of wellbeing in the context of migration and demonstrates the urgent need for policy reform
Best interests, durable solutions and belonging: future prospects for unaccompanied migrant minors coming of age in Europe
This paper sheds light on the ambiguous position of children who migrate without a parent or guardian as they become adults in the European Union (EU). Through a critical analysis of three prevailing frames (‘best interests’, ‘durable solutions’ and ‘belonging’), which largely inform policy and practice related to this group, it explores the tension between policy assumptions and what we know of the lived experiences and aspirations of these young people. It ultimately reveals a policy framework shaped by a state-centric view of migration, a static conception of belonging and a bias towards a political preference for return. Such a stance underestimates young people’s agency and willingness to embrace risk in their efforts to secure a viable future. The net result is policy which fails to offer a ‘durable solution’ or act in the ‘best interests’ of individual migrant young people or of society as a whole
Stellar Velocity Dispersion of the Leo A Dwarf Galaxy
We measure the first stellar velocity dispersion of the Leo A dwarf galaxy,
\sigma = 9.3 +- 1.3 km/s. We derive the velocity dispersion from the radial
velocities of ten young B supergiants and two HII regions in the central region
of Leo A. We estimate a projected mass of 8 +- 2.7 x10^7 solar masses within a
radius of 2 arcmin, and a mass to light ratio of at least 20 +- 6 M_sun/L_sun.
These results imply Leo A is at least ~80% dark matter by mass.Comment: 6 pages, accepted to Ap
Defining and measuring denigration of general practice in medical education
There is a workforce crisis in NHS general practice (GP). It is estimated that to meet future healthcare needs around 50% of current medical students will need to choose a career in GP. Positive role modelling is an influential factor in medical students’ career choice, but denigration of primary care during medical training may undermine the aspirations of students considering GP as a career. This article discusses the importance of medical schools detecting and managing denigration of GP in their curricula and, for the first time, suggests an objective approach to the measurement of denigration. Four facets which constitute denigration are discussed and proposed as a collective measure. These are: language used about GP, proportion of curriculum time spent by students in GP, accurate representation of the clinical content of GP and equity of funding between hospital and GP placements. Furthermore, we discuss the key ethical and legal challenges that are faced by medical schools and, indeed, healthcare settings, that need to be overcome to enable proactive measurement and management of denigration
Influence of a 12.8-km military load carriage activity on lower limb gait mechanics and muscle activity
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.The high stress fracture occurrence in military populations has been associated with frequent load carriage activities. This study aimed to assess the influence of load carriage and of completing a load carriage training activity on gait characteristics. Thirty-two Royal Marine recruits completed a 12.8-km load carriage activity as part of their military training. Data were collected during walking in military boots, pre and post-activity, with and without the additional load (35.5 kg). Ground contact time, lower limb sagittal plane kinematics and kinetics, and electromyographic variables were obtained for each condition. When carrying load, there was increased ground contact time, increased joint flexion and joint moments, and increased plantar flexor and knee extensor muscle activity. Post-activity, there were no changes to kinematic variables, knee extensor moments were reduced, and there was evidence of plantar flexor muscle fatigue. The observed gait changes may be associated with stress fracture development. Practitioner Summary: This study identified gait changes due to load carriage and after a military load carriage training activity. Such activities are associated with lower limb stress fractures. A pre-post study design was used. Gait mechanics changed to a greater extent when carrying load, than after completion of the activity when assessed without load.This work was part-funded by the Institute of Naval Medicine
Unsettling integration
As part of the three-year project “EPIC”, funded by the Asylum, Migration and Integration fund, this research explores the diversity of responses to migration accross eleven European urban spaces and the different strategies put in place by migrants to navigate and learn the city. To achieve its objective, the project has been designed to establish an international environment for building knowledge and exchanging good practices across multiple partners and sectors. The first chapter examines current migration and integration literature in order to dissect and move beyond the notion of integration. Incorporating policy discourse and academic analyses of integration frameworks and practice, the chapter provides a discursive context for and background to the need for concept revision and to how processes and practices of adaption are perceived of and understood. The second chapter discusses the findings of the surveys and interviews conducted across the eleven cities based on an alternative framework of care, repair and maintenance, drawing out the dominant dimensions and themes within subjective definitions and experiences of ‘integration’. The analysis underlines the importance of recognising the diversity in trajectories of integration, and that policy design should focus on removing obstacles to integration rather than imposing linear integration trajectories. The paper attempts to adopt a reflexive gaze throughout the research to acknowledge the position of power, privilege and in most cases whiteness of the researchers involved. It also recognise the limitations of this type of research and the fact that it is not meant to provide solutions. It wishes, however, to foster further reflections and address the challenges faced by local NGOs and governments
Altered forefoot function following a military training activity
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordBackground
Injury rates are high in populations that regularly undertake weight-bearing physical activity, particularly military populations. Military training activities, that often include load carriage, have been associated with lower limb injury occurrence, specifically stress fractures.
Research question
Recent work identified plantar loading variables as risk factors for lower limb stress fractures in Royal Marines recruits that were assessed during barefoot running. This study aimed to quantify how those plantar loading variables changed in Royal Marines recruits following a prolonged military load carriage activity, to further understand potential mechanisms for lower limb stress fractures.
Methods
Bilateral, synchronised plantar pressure and lower limb kinematic data were recorded during barefoot running at 3.6 m s-1 (±5%) pre- and post- a 12.8-km training activity (∼150 min). The training activity was completed with an average speed typical of walking (1.4 m.s-1), and 35.5 kg of additional load was carried throughout. Data were collected from 32 male Royal Marines recruits who completed the training activity in week-21 of the 32-week training programme. Plantar pressure variables and ankle dorsiflexion were compared between pre- and post-activity.
Results
Post-activity there was reduced loading under the forefoot and increased loading under the rearfoot and midfoot. There was no change in dorsiflexion touchdown angle, but an increase in peak dorsiflexion and range of motion post-activity.
Significance
The increased rearfoot loading, reduced forefoot loading and increased ankle dorsiflexion following a prolonged military load carriage activity suggest a reduced transfer of loading from the rearfoot to the forefoot during stance, which may have implications for the development of stress fractures, particularly of the metatarsals.Institute of Naval Medicin
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