384 research outputs found
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
Scientific possibilities of a solar electric powered rendezvous with comet Encke
The minimum scientific spacecraft instrumentation is considered that is likely to result in as complete an understanding of the composition, structure, and activity of a cometary nucleus as is possible without landing on it. The payload will also give useful results on secondary goals of a better understanding of physical processes in the inner and outer coma. Studies of composition, by means of an actual landing on the surface, details of the internal structure of the nucleus, and sample return were considered beyond the scope of this mission
Scientific questions for the exploration of the terrestrial planets and Jupiter - Advanced planetary missions technology program Progress report
Scientific questions and experimental design for planetary exploration of Jupiter, Mars, Mercury, and Venu
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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
Baseline microbial characterizations of an imperiled aquatic diversity hotspot: Ash Meadows National Wildlife Refuge
Located in the discharge zone of the Death Valley Flow System, Ash Meadows National Wildlife Refuge is a spring-fed desert oasis and biodiversity hotspot about 90 miles northwest of Las Vegas. These critical wetlands are potentially threatened by groundwater pumping, exotic species invasions, and climate change. Although a major component of the lower food web, very little is known about the microbial makeup of this ecosystem. As a first step towards understanding the microbial and biogeochemical aspects of this system, a detailed molecular-based characterization of microbial communities, baseline chemistry, and physical characteristics of various springs of Ash Meadows will be conducted over the summer of 2009. Specifically, springs will be compared using DNA extraction followed by PCR amplification of the 16s rRNA gene, DNA fingerprinting, cultivation, and flow cytometric cell counting
Young people today: news media, policy and youth justice
The new sociology of childhood sees children as competent social agents with important contributions to make. And yet the phase of childhood is fraught with tensions and contradictions. Public policies are required, not only to protect children, but also to control them and regulate their behaviour. For children and young people in the UK, youth justice has become increasingly punitive. At the same time, social policies have focused more on children's inclusion and participation. In this interplay of conflict and contradictions, the role the media play is critical in contributing to the moral panic about childhood and youth. In this article, we consider media representations of “antisocial” children and young people and how this belies a moral response to the nature of contemporary childhood. We conclude by considering how a rights-based approach might help redress the moralised politics of childhood representations in the media
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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
Notes on a scandal: the official enquiry into deviance and corruption in New Zealand police
Since 2004, the New Zealand Police Service has been engulfed by a series of scandals relating to allegations that officers have committed rape and sexual assault and conducted inappropriate sexual relations with vulnerable people. Moreover, it has been claimed that other officers engaged in corrupt practices to thwart the investigation and prosecution of criminal behaviour of police officers. In 2007, a Commission of Inquiry report established a program of reform intended to shape the future direction of the police service. This article provides an overview of these scandals, the context in which they have emerged, and the political and policing response to them. The analysis contained in the Commission report is compared with that offered by comparable investigations of police deviance and corruption in other countries. The methodological and conceptual limitations of the Commission are outlined and the prospects of the recommendations are considered
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The Birthplace in England national prospective cohort study: further analyses to enhance policy and service delivery decision-making for planned place of birth
Background: Evidence from the Birthplace in England Research Programme supported a policy of offering ‘low risk’ women a choice of birth setting, but a number of unanswered questions remained.
Aims: This project aimed to provide further evidence to support the development and delivery of maternity services and inform women’s choice of birth setting: specifically, to explore maternal and organisational factors associated with intervention, transfer and other outcomes in each birth setting in ‘low risk’ and ‘higher risk’ women.
Design: Five component studies using secondary analysis of the Birthplace prospective cohort study (studies 2–5) and ecological analysis of unit/NHS trust-level data (studies 1 and 5).
Setting: Obstetric units (OUs), alongside midwifery units (AMUs), freestanding midwifery units (FMUs) and planned home births in England.
Participants: Studies 1–4 focused on ‘low risk’ women with ‘term’ pregnancies planning vaginal birth in 43 AMUs (n = 16,573), in 53 FMUs (n = 11,210), at home in 147 NHS trusts (n = 16,632) and in a stratified, random sample of 36 OUs (n = 19,379) in 2008–10. Study 5 focused on women with pre-existing medical and obstetric risk factors (‘higher risk’ women).
Main outcome measures: Interventions (instrumental delivery, intrapartum caesarean section), a measure of low intervention (‘normal birth’), a measure of spontaneous vaginal birth without complications (‘straightforward birth’), transfer during labour and a composite measure of adverse perinatal outcome (‘intrapartum-related mortality and morbidity’ or neonatal admission within 48 hours for > 48 hours). In studies 1 and 3, rates of intervention/maternal outcome and transfer were adjusted for maternal characteristics.
Analysis: We used (a) funnel plots to explore variation in rates of intervention/maternal outcome and transfer between units/trusts, (b) simple, weighted linear regression to evaluate associations between unit/trust characteristics and rates of intervention/maternal outcome and transfer, (c) multivariable Poisson regression to evaluate associations between planned place of birth, maternal characteristics and study outcomes, and (d) logistic regression to investigate associations between time of day/day of the week and study outcomes.
Results: Study 1 – unit-/trust-level variations in rates of interventions, transfer and maternal outcomes were not explained by differences in maternal characteristics. The magnitude of identified associations between unit/trust characteristics and intervention, transfer and outcome rates was generally small, but some aspects of configuration were associated with rates of transfer and intervention. Study 2 – ‘low risk’ women planning non-OU birth had a reduced risk of intervention irrespective of ethnicity or area deprivation score. In nulliparous women planning non-OU birth the risk of intervention increased with increasing age, but women of all ages planning non-OU birth experienced a reduced risk of intervention. Study 3 – parity, maternal age, gestational age and ‘complicating conditions’ identified at the start of care in labour were independently associated with variation in the risk of transfer in ‘low risk’ women planning non-OU birth. Transfers did not vary by time of day/day of the week in any meaningful way. The duration of transfer from planned FMU and home births was around 50–60 minutes; transfers for ‘potentially urgent’ reasons were quicker than transfers for ‘non-urgent’ reasons. Study 4 – the occurrence of some interventions varied by time of the day/day of the week in ‘low risk’ women planning OU birth. Study 5 – ‘higher risk’ women planning birth in a non-OU setting had fewer risk factors than ‘higher risk’ women planning OU birth and these risk factors were different. Compared with ‘low risk’ women planning home birth, ‘higher risk’ women planning home birth had a significantly increased risk of our composite adverse perinatal outcome measure. However, in ‘higher risk’ women, the risk of this outcome was lower in planned home births than in planned OU births, even after adjustment for clinical risk factors.
Conclusions: Expansion in the capacity of non-OU intrapartum care could reduce intervention rates in ‘low risk’ women, and the benefits of midwifery-led intrapartum care apply to all ‘low risk’ women irrespective of age, ethnicity or area deprivation score. Intervention rates differ considerably between units, however, for reasons that are not understood. The impact of major changes in the configuration of maternity care on outcomes should be monitored and evaluated. The impact of non-clinical factors, including labour ward practices, staffing and skill mix and women’s preferences and expectations, on intervention requires further investigation. All women planning non-OU birth should be informed of their chances of transfer and, in particular, older nulliparous women and those more than 1 week past their due date should be advised of their increased chances of transfer. No change in the guidance on planning place of birth for ‘higher risk’ women is recommended, but research is required to evaluate the safety of planned AMU birth for women with selected relatively common risk factors.
Funding: The National Institute for Health Research Health Services and Delivery Research programme
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The Birthplace national prospective cohort study: perinatal and maternal outcomes by planned place of birth Birthplace in England research programme.
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