1,899 research outputs found
Evidence for Proportionate Partition Between the Magnetic Field and Hot Gas in Turbulent Cassiopeia A
We present a deep X-ray observation of the young Galactic supernova remnant
Cas A, acquired with the ROSAT High Resolution Imager. This high dynamic range
(232 ks) image reveals low-surface-brightness X-ray structure, which appears
qualitatively similar to corresponding radio features. We consider the
correlation between the X-ray and radio morphologies and its physical
implications. After correcting for the inhomogeneous absorption across the
remnant, we performed a point by point (4" resolution) surface brightness
comparison between the X-ray and radio images. We find a strong (r = 0.75)
log-log correlation, implying an overall relationship of . This is
consistent with proportionate partition (and possibly equipartition) between
the local magnetic field and the hot gas --- implying that Cas A's plasma is
fully turbulent and continuously amplifying the magnetic field.Comment: 8 pages with embedded bitmapped figures, Accepted by ApJ Letters
5/1/9
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Signals to their parliaments? Governmentsâ use of votes and policy statements in the EU Council
Does parliamentary oversight of governmentsâ decisions in the international arena matter? This article finds that it does: governments with strong parliamentary oversight behave differently when negotiating policies at the EU level compared with governments with less powerful parliaments. Where parliaments have formal powers to oversee and restrict their government's positions we see a significantly higher use of opposing votes and formal policy statements by those governments. This behaviour intensifies depending on the governments' standing visâĂ âvis other political parties at home. When governments are under pressure in their national parliaments they are more likely to go on record and take a stand against the majority in Brussels. These results make it clear that in EU legislative politics, governments not only consider their policy priorities and negotiation tactics with their European counterparts, but also make use of EU decision records to send signals to domestic audiences, including their national parliaments
Evaluation of a gender-sensitive physical activity programme for inactive men in Ireland: Protocol paper for a pragmatic controlled trial
The excess burden of ill-health, mortality and premature death experienced by many men, and poorer men in particular, across the developed world has prompted calls for the development of gender sensitised health related services for men. An emergent body of evidence indicates that successful public health work with men can be accomplished when it utilises elements with which men are familiar and secure. In particular, physical activity (PA) is proven here to be a useful âhookâ to engage men. âMen on the Moveâ (MoM) is a community-based PA programme designed to engage inactive men to improve their overall health and well-being. The MoM programme was delivered by practitioner partnerships in diverse communities and among diverse groups of men under âreal worldâ conditions to assess both its efficacy and replicability with a view to scaling-up the programme nationally for population wide impact. Establishing appropriate protocols is critical when conducting research that translates into practice, is replicable in practice and can be disseminated at a population level. The purpose of this paper is to detail the protocols used in the design, implementation and evaluation of the MoM programme. Specifically, the process of engaging men in a community based PA intervention and sustaining that engagement over the 12 weeks and the protocols used to evaluate the impact of participation in MoM on biopsychosocial health up to 52 weeks will be outlined. If the intervention proves successful, gender-sensitive community based PA interventions for men could be a promising avenue to address their health needs. These findings may be of support to both practitioners endeavouring to engage men and others engaged in translational research to ensure their research translates to meaningful action in practice
The impact of a gender-specific physical activity intervention on the fitness and fatness profile of men in Ireland
Background: Amid increasing concerns about rising obesity rates and unhealthy lifestyle behaviours, physical activity (PA) is seen as a prophylactic to many chronic conditions affecting men. Men respond best to community-based PA programmes, using gender-specific promotional and delivery strategies. âMen on the Moveâ (MOM) was developed on this basis and targeted inactive adult men in Ireland.
Methods: Sedentary men (n=927; age=50.7±10.9yr; Weight=92.7±16.0kg; METS=6.06±2.13) were recruited across 8 counties; 4 âintervention groupâ (IG; n=501), and 4 âcomparison-in-waiting groupâ (CG; n=426). The MOM programme involved structured group exercise twice weekly for 12 weeks, along with health-related workshops with the groups maintained up to 52W. Primary outcome measures (aerobic fitness, bodyweight and waist circumference (WC)) together with self-administered questionnaires were used to gather participant data at baseline, 12, 26 and 52 weeks (W).
Results: Results show a net positive effect on aerobic fitness, bodyweight and WC, with significant (p<0.05) net change scores observed in the IG compared to the CG (METS: 12W=+2.20, 26W=+1.89, 52W=+0.92; Weight: 12W=-1.72kg, 26W=-1.95kg, 52W=-1.89kg; WC: 12W=-4.54cm, 26W=-2.69cm, 52W=-3.16cm). The corresponding reduction in cardiovascular disease risk is particularly significant in the context of a previously inactive and overweight cohort. The high âdropoutâ (42.7% presenting at 52W) however, is of particular concern, with âdropoutsâ having lower levels of aerobic fitness and higher bodyweight/WC at baseline.
Conclusions: Notwithstanding dropout issues, findings address an important gap in public health practice by informing the translational scale-up of a small controllable gender-specific PA intervention, MOM, to a national population based PA intervention targeting inactive men
A Broadband X-Ray Study of the Supernova Remnant 3C 397
We present an X-ray study of the radio bright supernova remnant (SNR) 3C 397
with ROSAT, ASCA, and RXTE. A central X-ray spot seen with the ROSAT
High-Resolution Imager hints at the presence of a pulsar-powered component, and
gives this SNR a composite X-ray morphology. Combined ROSAT and ASCA imaging
show that the remnant is highly asymmetric, with its hard X-ray emission
peaking at the western lobe. The spectrum of 3C 397 is heavily absorbed, and
dominated by thermal emission with emission lines evident from Mg, Si, S, Ar
and Fe. Single-component models fail to describe the spectrum, and at least two
components are required. We use a set of non-equilibrium ionization (NEI)
models (Borkowski et al. in preparation). The temperatures from the soft and
hard components are 0.2 keV and 1.6 keV respectively. The corresponding
ionization time-scales ( being the pre-shock hydrogen density) are
6 cm s and 6 10 cm s,
respectively. The spectrum obtained with the Proportional Counter Array (PCA)
of RXTE is contaminated by emission from the Galactic ridge, with only
15% of the count rate originating from 3C 397 in the 5-15 keV range. The PCA
spectrum allowed us to confirm the thermal nature of the hard X-ray emission. A
third component originating from a pulsar-driven component is possible, but the
contamination of the source signal by the Galactic ridge did not allow us to
find pulsations from any hidden pulsar. We discuss the X-ray spectrum in the
light of two scenarios: a young ejecta-dominated remnant of a core-collapse SN,
and a middle-aged SNR expanding in a dense ISM. Spatially resolved spectroscopy
(with CHANDRA and XMM) is needed to differentiate between the two scenarios,
and address the nature of the mysterious radio-quiet X-ray hot spot.Comment: 21 pages including 8 figures and 5 tables. Accepted for publication
in the Astrophysical journa
Expert advice and political choice in constructing European banking union
International actors promoted the transfer of regulatory authority and financial resources from national governments to the European Union (EU) in the context of establishing the prerequisites for financial stability in Europe through banking union. It was supplied, however, by a political process that kept significant resources in resolution and deposit insurance largely in national hands. This article examines the politics behind those decisions, and how the hybrid of European and national competences affects bank regulation and financial stability in the EU. It concludes that the tension between strong EU supervisory powers and weak capacity to deal with insolvent institutions will persist
A Bow Shock Nebula Around a Compact X-Ray Source in the Supernova Remnant IC443
We present spectra and high resolution images of the hard X-ray feature along
the southern edge of the supernova remnant IC443. Data from the Chandra X-ray
Observatory reveal a comet-shaped nebula of hard emission, which contains a
softer point source at its apex. We also present 20cm, 6cm, and 3.5cm images
from the Very Large Array that clearly show the cometary nebula. Based on the
radio and X-ray morphology and spectrum, and the radio polarization properties,
we argue that this object is a synchrotron nebula powered by the compact source
that is physically associated with IC443. The spectrum of the soft point source
is adequately but not uniquely fit by a black body model (kT=0.71 +/- 0.08 keV,
L=(6.5 +/- 0.9) * 10^31 erg/s). The cometary morphology of the nebula is the
result of the supersonic motion of the neutron star (V_NS=250 +/- 50 km/s),
which causes the relativistic wind of the pulsar to terminate in a bow shock
and trail behind as a synchrotron tail. This velocity is consistent with an age
of 30,000 years for the SNR and its associated neutron star.Comment: 9 pages, 5 figures, accepted for publication in the ApJ Letter
Recycling bins, garbage cans or think tanks? Three myths regarding policy analysis institutes
The phrase 'think tank' has become ubiquitous â overworked and underspecified â in the political lexicon. It is entrenched in scholarly discussions of public policy as well as in the 'policy wonk' of journalists, lobbyists and spin-doctors. This does not mean that there is an agreed definition of think tank or consensual understanding of their roles and functions. Nevertheless, the majority of organizations with this label undertake policy research of some kind. The idea of think tanks as a research communication 'bridge' presupposes that there are discernible boundaries between (social) science and policy. This paper will investigate some of these boundaries. The frontiers are not only organizational and legal; they also exist in how the 'public interest' is conceived by these bodies and their financiers. Moreover, the social interactions and exchanges involved in 'bridging', themselves muddy the conception of 'boundary', allowing for analysis to go beyond the dualism imposed in seeing science on one side of the bridge, and the state on the other, to address the complex relations between experts and public policy
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