490 research outputs found
A model of the physical properties of comet Encke
The available observational data on periodic comet Encke were collected and interpreted in order to construct a model of the comet. The model is intended for use in the design of scientific experiments and spacecraft systems to be used on future missions to Encke. Numerical values and ranges of uncertainty are given for all of the important structural, compositional, and photometric parameters with references to the original research from which these were calculated or estimated
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The Midwifery Unit Network: creating a community of practice to enhance maternity services
The Midwifery Unit Network (MUNet) is a community of practice which aims to promote and support the implementation and improvement of midwifery units (MUs) in the UK and internationally. It was launched in April 2016 and has been growing fast since its inception. In this article the co-leads of the MUNet describe how they established the network, and the challenges that they had to overcome. The aim of this article is to inspire more midwives and parent advocates to consider establishing a community of practice, and to offer some guidance on the key aspects involved
Mission to a comet - Preliminary scientific objectives and experiments for use in advanced mission studies
Scientific objectives and experiments for comet missio
Spectroscopic Observations of New Oort Cloud Comet 2006 VZ13 and Four Other Comets
Spectral data are presented for comets 2006 VZ13 (LINEAR), 2006 K4 (NEAT),
2006 OF2 (Broughton), 2P/Encke, and 93P/Lovas I, obtained with the Cerro-Tololo
Inter-American Observatory 1.5-m telescope in August 2007. Comet 2006 VZ13 is a
new Oort cloud comet and shows strong lines of CN (3880 angstroms), the Swan
band sequence for C_2 (4740, 5160, and 5630 angstroms), C_3 (4056 angstroms),
and other faint species. Lines are also identified in the spectra of the other
comets. Flux measurements of the CN, C_2 (Delta v = +1,0), and C_3 lines are
recorded for each comet and production rates and ratios are derived. When
considering the comets as a group, there is a correlation of C_2 and C_3
production with CN, but there is no conclusive evidence that the production
rate ratios depend on heliocentric distance. The continuum is also measured,
and the dust production and dust-to-gas ratios are calculated. There is a
general trend, for the group of comets, between the dust-to-gas ratio and
heliocentric distance, but it does not depend on dynamical age or class. Comet
2006 VZ13 is determined to be in the carbon-depleted (or Tempel 1 type) class.Comment: 8 pages, 6 figures, 6 tables; Accepted by MNRA
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Births and their outcomes by time, day and year: a retrospective birth cohort data linkage study
Background
Studies of daily variations in the numbers of births in England and Wales since the 1970s have found a pronounced weekly cycle, with numbers of daily births being highest from Tuesdays to Fridays and lowest at weekends and on public holidays. Mortality appeared to be higher at weekends. As time of birth was not included in national data systems until 2005, there have been no previous analyses by time of day.
Objectives
To link data from birth registration and birth notification to data about care during birth and any subsequent hospital admissions and to quality assure the linkage. To use the linked data to analyse births and their outcomes by time of day, day of the week and year of birth.
Design
A retrospective birth cohort analysis of linked routine data.
Setting
England and Wales.
Outcome measures
Mortality of babies and mothers, and morbidity recorded at birth and any subsequent hospital admission.
Population and data sources
Birth registration and notification records of 7,013,804 births in 2005–14, already linked to subsequent death registration records for babies, children and women who died within 1 year of giving birth, were provided by the Office for National Statistics. Stillbirths and neonatal deaths data from confidential enquiries for 2005–9 were linked to the registration records. Data for England were linked to Hospital Episode Statistics (HES) and data for Wales were linked to the Patient Episode Database for Wales and the National Community Child Health Database.
Results
Cross-sectional analysis of all births in England and Wales showed a regular weekly cycle. Numbers of births each day increased from Mondays to Fridays. Numbers were lowest at weekends and on public holidays. Overall, numbers of births peaked between 09.00 and 12.00, followed by a much smaller peak in the early afternoon and a decrease after 17.00. Numbers then increased from 20.00, peaking at around 03.00–05.00, before falling again after 06.00. Singleton births after spontaneous onset and birth, including births in freestanding midwifery units and at home, were most likely to occur between midnight and 06.00, peaking at 04.00–06.00. Elective caesarean births were concentrated in weekday mornings. Births after induced labours were more likely to occur at hours around midnight on Tuesdays to Saturdays, irrespective of the mode of birth.
Limitations
The project was delayed by data access and information technology infrastructure problems. Data from confidential enquiries were available only for 2005–9 and some HES variables were incomplete. There was insufficient time to analyse the mortality and morbidity outcomes.
Conclusions
The timing of birth varies by place of birth, onset of labour and mode of birth. These patterns have implications for midwifery and medical staffing.
Future work
An application has now been submitted for funding to analyse the mortality outcomes and further funding will be sought to undertake the other outstanding analyses.
Funding
This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 7, No. 18. See the NIHR Journals Library website for further project information
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Mapping maternity care: the configuration of maternity care in England. Birthplace in England research programme
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Involving service users in Births and their outcomes: a retrospective birth cohort data linkage study analysing daily, weekly and yearly cycles and their implications for the NHS
Introduction
We report on service user participation in ‘Births and their Outcomes’, a population-based, retrospective, birth cohort, data linkage study to analyse the daily, weekly and yearly cycles of births and their implications for the NHS. Although Public Involvement and Engagement (PI&E), also referred to here as Patient and Public Involvement (PPI), has a long history in maternity services, PI&E in maternity data linkage studies is new. We have reported using the GRIPP2 short form.
Objectives
We aimed to involve and engage a wide range of maternity service users and their representatives to ensure that our use of routinely collected maternity and birth records was acceptable and that our research analyses using linked data were relevant to their expressed safety and quality of care needs.
Methods
A three-tiered approach to PPI was used. Having both PPI co-investigators and PPI members of the Study Advisory Group ensured service user involvement was part of the strategic development of the project. A larger constituency of maternity service users was engaged through four workshops held throughout England.
Results
Two co-investigators with experience of PPI in maternity research were involved from design stage to dissemination. Four PPI study advisors contributed service user perspectives. Engagement workshops attracted around 100 attendees, recruited largely from Maternity Services Liaison Committees and a community engagement group. They supported use of the data, believing the study had potential to improve safety and quality of maternity services. They contributed their experiences and concerns which will assist with interpretation of the analyses.
Conclusion
Use of PPI ‘knowledge intermediaries’ successfully bridged the gap between data intensive research and lived experience, but more inclusivity in involvement and engagement is required. The concerns and questions of service users provide social legitimacy and a relevance framework for researchers carrying out analyses
The digital archive of the International Halley Watch
The International Halley Watch was established to coordinate, collect, archive, and distribute the scientific data from Comet P/Halley that would be obtained from both the ground and space. This paper describes one of the end products of that effort, namely the IHW Digital Archive. The IHW Digital Archive consists of 26 CD-ROM's containing over 32 gigabytes of data from the 9 IHW disciplines as well as data from the 5 spacecraft missions flown to comet P/Haley and P/Giacobini-Zinner. The total archive contains over 50,000 observations by 1,500 observers from at least 40 countries. The first 24 CD's, which are currently available, contain data from the 9 IHW disciplines. The two remaining CD's will have the spacecraft data and should be available within the next year. A test CD-ROM of these data has been created and is currently under review
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The Stardust – a successful encounter with the remarkable comet Wild 2
On January 2, 2004 the Stardust spacecraft completed a close flyby of comet Wild2 (P81). Flying at a relative speed of 6.1 km/s within 237km of the 5 km nucleus, the spacecraft took 72 close-in images, measured the flux of impacting particles and did TOF mass spectrometry
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