4,375 research outputs found
On the fine structure of medium energy electron fluxes in the auroral zone and related effects in the ionospheric D-region
This study is based on measurements of trapped and precipitated electrons of energy >30 keV and >100 keV observed by
polar orbiting environmental satellites during overpasses of the imaging riometer at Kilpisjärvi, Finland.
The satellites are in sun-synchronous orbits of about 850 km altitude, recording the electron fluxes at 2-s time resolution.
The riometer measures the radiowave absorption at 38.2 MHz, showing the spatial pattern within a 240 km field of view.
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The analysis has focussed on two areas.
Having found a close correlation between the radiowave absorption and the medium-energy electron fluxes during satellite overpasses,
empirical relationships are derived, enabling one quantity to be predicted from the other for three sectors of local time.
It is shown that small-scale variations observed during a pass are essentially spatial rather than temporal.
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Other properties, such as the spectra and the relation between precipitated and trapped components, are also considered in the light of the theory
of pitch angle scattering by VLF waves.
It is found that the properties and behaviour depend strongly on the time of day.
In the noon sector, the precipitated and trapped fluxes are highly correlated through a square law relationship
Small carbon chains in circumstellar envelopes
Observations were made for a number of carbon-rich circumstellar envelopes
using the Phoenix spectrograph on the Gemini South telescope to determine the
abundance of small carbon chain molecules. Vibration-rotation lines of the
antisymmetric stretch of C near 2040 cm (4.902 m)
have been used to determine the column density for four carbon-rich
circumstellar envelopes: CRL 865, CRL 1922, CRL 2023 and IRC +10216. We
additionally calculate the column density of C for IRC +10216, and
provide an upper limit for 5 more objects. An upper limit estimate for the
C column density is also provided for IRC+10216. A comparison of these
column densities suggest a revision to current circumstellar chemical models
may be needed
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Access to healthcare for people seeking and refused asylum in Great Britain: a review of evidence
This research report is a review of evidence looking at the barriers people seeking or refused asylum face in trying to access healthcare services in the UK, and what may help them to do so more easily.
This report, and the partner report on lived experiences (https://www.equalityhumanrights.com/en/publication-download/lived-experiences-access-healthcare-people-seeking-and-refused-asylum), will be of interest to people who play an important role in delivering healthcare and related support services to people seeking or refused asylum.
We have also made recommendations for what changes are needed (https://www.equalityhumanrights.com/en/publication-download/making-sure-people-seeking-and-refused-asylum-can-access-healthcare-what-needs) to make sure that people seeking and refused asylum have full enjoyment of their right to health.
This review was carried out by Imperial College London, with primary data provided by Doctors of the World UK
The estimation of D-region electron densities from riometer data
International audienceAt high latitude the hard electron precipitation associated with auroral activity is a major source of ionization for the D-region, one consequence being the absorption of radio waves. Direct measurements of the D-region electron density are not readily available, however. This paper investigates the relationship between the electron density at altitudes between 100 and 70 km and the total radio absorption observed with a riometer, with a view to using the latter to predict the former. Tables are given of the median electron density corresponding to 1 dB absorption at 27.6 MHz for each hour of the day, and it is shown that at certain heights the estimates will be accurate to within a factor of 1.6 on 50% of the occasions. A systematic variation with time of day is probably associated with a progressive hardening of the typical electron spectrum during the morning hours. There is also evidence for a seasonal effect possibly due to seasonal variations of the mesosphere
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The lived experiences of access to healthcare for people seeking and refused asylum
This research aims to explore the lived experiences of accessing healthcare among people currently seeking asylum and those who have had their claim for asylum refused, as well as the experiences of health service providers working with these communities.
It examines the extent to which people are able to exercise their rights to access healthcare. It looks at the differences between those currently in the asylum system and those who have had their claim refused in England, Scotland and Wales.
This report, and the partner report providing a review of evidence (https://www.equalityhumanrights.com/en/publication-download/access-healthcare-people-seeking-and-refused-asylum-great-britain-review), will be of interest to people who play an important role in delivering healthcare and related support services to people seeking or refused asylum.
We have also made recommendations for what changes are needed (https://www.equalityhumanrights.com/en/publication-download/making-sure-people-seeking-and-refused-asylum-can-access-healthcare-what-needs) to make sure that people seeking and refused asylum have full enjoyment of their right to health.
This report was produced in collaboration with Imperial College London and Doctors of the World UK
The measurement of household socio-economic position in tuberculosis prevalence surveys: a sensitivity analysis.
OBJECTIVE: To assess the robustness of socio-economic inequalities in tuberculosis (TB) prevalence surveys. DESIGN: Data were drawn from the TB prevalence survey conducted in Lusaka Province, Zambia, in 2005-2006. We compared TB socio-economic inequalities measured through an asset-based index (Index 0) using principal component analysis (PCA) with those observed using three alternative indices: Index 1 and Index 2 accounted respectively for the biases resulting from the inclusion of urban assets and food-related variables in Index 0. Index 3 was built using regression-based analysis instead of PCA to account for the effect of using a different assets weighting strategy. RESULTS: Household socio-economic position (SEP) was significantly associated with prevalent TB, regardless of the index used; however, the magnitude of inequalities did vary across indices. A strong association was found for Index 2, suggesting that the exclusion of food-related variables did not reduce the extent of association between SEP and prevalent TB. The weakest association was found for Index 1, indicating that the exclusion of urban assets did not lead to higher extent of TB inequalities. CONCLUSION: TB socio-economic inequalities seem to be robust to the choice of SEP indicator. The epidemiological meaning of the different extent of TB inequalities is unclear. Further studies are needed to confirm our conclusions
Intervention Mapping: Physical Activity with Socially Disadvantaged Women - ePoster
Introduction Socially disadvantaged women (SDW) have lower levels of physical activity (PA), health inequalities and poorer health outcomes. These are associated with social determinants of health, e.g. Socioeconomic position and ethnic minority. Developing effective behaviour change programmes for SDW is complex due to disparities such as limited income and/or culturally inappropriate settings. These intricacies are often overlooked in PA policy. Consequently, interventions aimed at SDW often fail to show adequate reach, adoption and/or maintenance of PA. Therefore, we aim to inform policy and practice by developing needs-led PA interventions with SDW using Intervention Mapping (IM). IM begins with a needs assessment and follows an iterative six step process for planning interventions. Method Needs assessment tasks involved regular researcher participation in local PA sessions with SDW. The researcher also conducted 17 semi-structured interviews with SDW and community PA practitioners on the topic of PA. This data was thematically analysed and used within the first step of IM: to create a logic model of the PA health problem. Results Data gathered from interviews shows PA variety and suitable opportunities in Leeds and surrounding areas are lacking for SDW. These insights have demonstrated that the needs of SDW are essential to inform IM, PA policy and practice. Conclusion IM begins with a needs-led approach when tackling the health problem of inactivity for SDW. IM will continue to be used to design a comprehensive tool for practice and inform PA policy for SDW
Improved Searches for HI in Three Dwarf Spheroidal Galaxies
Previous searches for HI in our Galaxy's dwarf spheroidal companions have not
been complete enough to settle the question of whether or not these galaxies
have HI, especially in their outer parts. We present VLA observations of three
dwarf spheroidals: Fornax, Leo II, and Draco, all of which have known stellar
velocities. The new data show no HI emission or absorption. Column density
limits in emission are 4--7 x 10^18 atoms/cm^2 in the centers of the galaxies.
The importance of the new observations is that they cover larger areas than
previous searches and they are less plagued by confusion with foreground
(Galactic) HI. The apparent absence of neutral gas in the Fornax dwarf
spheroidal is especially puzzling because recent photometry shows evidence of
stars only 10^8 years old. We discuss whether the VLA observations could have
missed significant amounts of HI.Comment: 20 pages, 7 figures; to appear in the Astronomical Journa
Establishing Social Work Practices in England: The Early Evidence
Social Work Practices (SWPs) were established in England in 2009 to deliver social work services to looked after children and care leavers. The introduction of independent social work-led organisations generated controversy focused on issues such as the privatisation of children's services and social workers' conditions of employment. This paper reports early findings from the evaluation of four of these pilots, drawing on interviews with children and young people, staff, and local authority and national stakeholders. The SWPs assumed a variety of organisational forms. The procurement process was demanding, with protracted negotiations over matters such as budgetary control and providing a round-the-clock service. Start-up was facilitated by an established relationship between the SWP provider and the local authority. Once operational, SWPs continued to rely on local authorities for various functions; in most cases, local authorities retained control of placement budgets. Levels of consultation and choice offered to children and young people regarding the move to an SWP varied considerably. Children's understanding about SWPs was generally low except in the pilot where most children retained their original social worker. These early findings show some dilution of the original SWP model, while the pilots' diversity allows the benefits of particular models to emerge
Creating year 7 bubbles to support primary to secondary school transition: a positive pandemic outcome?
In this paper, we explore the benefits of new forms of in-school grouping for children moving from primary to secondary school during the COVID-19 pandemic in England. Our three-phase study with over 400 students and teachers found that protective measures to limit COVID-19 though year group ‘bubbles’ generated an environment more aligned to children’s previous primary school experience. This natural experiment smoothed the process of transition by providing a better correspondence with students’ developmental needs, especially for those on the cusp of adolescence. We recommend that physical, administrative and pedagogical school structures are reimagined for this age group to this end
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