1,918 research outputs found
Poly-substance use and sexual risk behaviours: a cross-sectional comparison of adolescents in mainstream and alternative education settings
Background:
Surveys of young people under-represent those in alternative education settings (AES), potentially disguising health inequalities. We present the first quantitative UK evidence of health inequalities between AES and mainstream education school (MES) pupils, assessing whether observed inequalities are attributable to socioeconomic, familial, educational and peer factors.
Methods:
Cross-sectional, self-reported data on individual- and poly-substance use (PSU: combined tobacco, alcohol and cannabis use) and sexual risk-taking from 219 pupils in AES (mean age 15.9 years) were compared with data from 4024 pupils in MES (mean age 15.5 years). Data were collected from 2008 to 2009 as part of the quasi-experimental evaluation of Healthy Respect 2 (HR2).
Results:
AES pupils reported higher levels of substance use, including tobacco use, weekly drunkenness, using cannabis at least once a week and engaging in PSU at least once a week. AES pupils also reported higher levels of sexual health risk behaviours than their MES counterparts, including: earlier sexual activity; less protection against sexually transmitted infections (STIs); and having 3+ lifetime sexual partners. In multivariate analyses, inequalities in sexual risk-taking were fully explained after adjusting for higher deprivation, lower parental monitoring, lower parent-child connectedness, school disengagement and heightened intentions towards early parenthood among AES vs MES pupils. However, an increased risk (OR = 1.73, 95% CI 1.15, 2.60) of weekly PSU was found for AES vs MES pupils after adjusting for these factors and the influence of peer behaviours.
Conclusion:
AES pupils are more likely to engage in health risk behaviours, including PSU and sexual risk-taking, compared with MES pupils. AES pupils are a vulnerable group who may not be easily targeted by conventional population-level public health programmes. Health promotion interventions need to be tailored and contextualised for AES pupils, in particular for sexual health and PSU. These could be included within interventions designed to promote broader outcomes such as mental wellbeing, educational engagement, raise future aspirations and promote resilience
A physical interpretation of the jet-like X-ray emission from supernova remnant W49B
In the framework of the study of supernova remnants and their complex
interaction with the interstellar medium and the circumstellar material, we
focus on the galactic supernova remnant W49B. Its morphology exhibits an X-ray
bright elongated nebula, terminated on its eastern end by a sharp perpendicular
structure aligned with the radio shell. The X-ray spectrum of W49B is
characterized by strong K emission lines from Si, S, Ar, Ca, and Fe. There is a
variation of the temperature in the remnant with the highest temperature found
in the eastern side and the lowest one in the western side. The analysis of the
recent observations of W49B indicates that the remnant may be the result of an
asymmetric bipolar explosion where the ejecta are collimated along a jet-like
structure and the eastern jet is hotter and more Fe-rich than the western one.
Another possible scenario associates the X-ray emission with a spherical
explosion where parts of the ejecta are interacting with a dense belt of
ambient material. To overcome this ambiguity we present new results of the
analysis of an XMM-Newton observation and we perform estimates of the mass and
energy of the remnant. We conclude that the scenario of an anisotropic jet-like
explosion explains quite naturally our observation results, but the association
of W49B with a hypernova and a gamma-ray burst, although still possible, is not
directly supported by any evidence.Comment: 7 pages, 5 figures, accepted for publication in Advances in Space
Researc
Divergence or convergence? Health inequalities and policy in a devolved Britain
Since the advent of political devolution in the UK, it has been widely reported that markedly different health policies have emerged. However, most of these analyses are based on a comparison of health care policies and, as such, only tell part of a complex and evolving story. This paper
considers official responses to a shared public health policy aim, the reduction of health inequalities, through an examination of national policy statements produced in England, Scotland and Wales respectively since 1997. The analysis suggests that the relatively consistent manner in
which the ‘policy problem’ of health inequalities has been framed combined with the dominance of a medical model of health have constrained policy responses. Our findings differ from existing analyses, raising some important questions about the actuality of, and scope for, policy divergence since devolution
The Direct Sensing of Damage to Ion Implanted Materials
Material damage caused by the implantation of a high concentration of hydrogenic ions requires regular remote monitoring in order to study the atomic and nuclear reaction processes taking place within each sample. Real time continuous measurements of acoustic emission, X-ray production and emitted particle flux enable processes such as bubble or crack formation, changes in crystalline order, and nuclear fusion reactions can be studied in detail through examination of secondary or associated emission products. Fracturing of a material may generate a unique signature which, when taken in conjunction with time-averaged quantities such as changes in resistivity, surface strain, and induced radioactivity, enable an overall picture of the onset and nature of crack formation to be acquired. The overall usefulness of the remote sensing of damage processes and nuclear reactions is discussed. Surface studies involving inelastic Raman scattering and atomic force spectroscopy can contribute substantially to the overall picture, and identify clustering and cluster processes
A search for X-ray emission from rich clusters, extended halos around clusters, and superclusters
The all-sky data base acquired with the HEAO A-2 experiment was searched for X-ray emission on a variety of metagalactic size scales which were either predicted or previously detected. Results in the 0.2-60 keV energy range are presented. The optically richest clusters, including those from which a microwave decrement were observed, appear to be relatively underluminous in X-rays. Observations of Abell 576 show its luminosity to be less than earlier estimates, and moreover less than the luminosity predicted from its microwave decrement, unless the intracluster gas is a factor of approximately 10 hotter than in typical clusters. Near SC0627 there are two X-ray sources, and the identification of the dominant source with SCO627 is probably incorrect. New spectral observations of Abell 401 and 2147, possible superclusters, reveal that they have typical cluster spectra with iron line emission
The pre-ZAMS nature of Mol160/IRAS23385+6053 confirmed by Spitzer
Determining the timeline for the formation of massive YSOs requires the
identification and characterisation of all the phases that a massive forming
YSO undergoes. It is of particular interest to verify the observability of the
phase in which the object is rapidly accreting while not yet igniting the
fusion of hydrogen that marks the arrival on the ZAMS. One of the candidate
prototypical objects for this phase is Mol160/IRAS23385+6053, which previous
studies suggest it could be in a pre-Hot Core stage. We further investigate
this issue by means of Spitzer imaging and spectroscopy in the 5-70 micron
range. The dense core of Mol160/IRAS23385+6053, which up to now had only been
detected at submm and mm wavelenghts has been revealed for the first time at 24
and 70 micron by Spitzer. The complete 24 micron -3.4 mm continuum cannot be
fitted with a standard model of a Zero-Age Main-Sequence (ZAMS) star embedded
in an envelope. A simple greybody fit yields a mass of 220 solar masses. The
luminosity is slightly in excess of 3000 solar luminosities, which is a factor
of 5 less than previous estimates when only IRAS fluxes were available between
20 and 100 micron. The source is under-luminous by the same factor with respect
to UCHII regions or Hot-Cores of similar circumstellar mass, and simple models
show that this is compatible with an earlier evolutionary stage. Spectroscopy
between 5 and 40 microns revelas typical PDR/PIR conditions, where the required
UV illumination may be provided by other sources revealed at 24 microns in the
same region, and which can be plausibly modeled as moderately embedded
intermediate-mass ZAMS stars. Our results strengthen the suggestion that the
central core in Mol160/IRAS23385+6053 is a massive YSO actively accreting from
its circumstellar envelope and which did not yet begin hydrogen fusion.Comment: Accepted by A&
Climate profile for the McCallum Emria study area
March 1981.Includes bibliographical references (page 64)
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