305 research outputs found
Mission to a comet - Preliminary scientific objectives and experiments for use in advanced mission studies
Scientific objectives and experiments for comet missio
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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Mapping maternity care: the configuration of maternity care in England. Birthplace in England research programme
Venus - Preliminary science objectives and experiments for use in advanced mission studies
Mission planning and experiment design for future Mariner-type Venus space probe
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The Stardust â 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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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 âlow riskâ 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 womenâs choice of birth setting: specifically, to explore maternal and organisational factors associated with intervention, transfer and other outcomes in each birth setting in âlow riskâ and âhigher riskâ women.
Design: Five component studies using secondary analysis of the Birthplace prospective cohort study (studies 2â5) 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 1â4 focused on âlow riskâ women with âtermâ pregnancies planning vaginal birth in 43 AMUs (nâ=â16,573), in 53 FMUs (nâ=â11,210), at home in 147 NHS trusts (nâ=â16,632) and in a stratified, random sample of 36 OUs (nâ=â19,379) in 2008â10. Study 5 focused on women with pre-existing medical and obstetric risk factors (âhigher riskâ women).
Main outcome measures: Interventions (instrumental delivery, intrapartum caesarean section), a measure of low intervention (ânormal birthâ), a measure of spontaneous vaginal birth without complications (âstraightforward birthâ), transfer during labour and a composite measure of adverse perinatal outcome (âintrapartum-related mortality and morbidityâ or neonatal admission within 48 hours for >â48 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 â 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 â âlow riskâ 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 â parity, maternal age, gestational age and âcomplicating conditionsâ identified at the start of care in labour were independently associated with variation in the risk of transfer in âlow riskâ 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 50â60 minutes; transfers for âpotentially urgentâ reasons were quicker than transfers for ânon-urgentâ reasons. Study 4 â the occurrence of some interventions varied by time of the day/day of the week in âlow riskâ women planning OU birth. Study 5 â âhigher riskâ women planning birth in a non-OU setting had fewer risk factors than âhigher riskâ women planning OU birth and these risk factors were different. Compared with âlow riskâ women planning home birth, âhigher riskâ women planning home birth had a significantly increased risk of our composite adverse perinatal outcome measure. However, in âhigher riskâ 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 âlow riskâ women, and the benefits of midwifery-led intrapartum care apply to all âlow riskâ 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 womenâs 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 âhigher riskâ 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
Perinatal and maternal outcomes in planned home and obstetric unit births in women at âhigher riskâ of complications: secondary analysis of the Birthplace national prospective cohort study
Objective: To explore and compare perinatal and maternal outcomes in women at âhigher riskâ of complications planning home versus obstetric unit (OU) birth.
Design: Prospective cohort study.
Setting: OUs and planned home births in England.
Population: 8180 âhigher riskâ women in the Birthplace cohort.
Methods: We used Poisson regression to calculate relative risks adjusted for maternal characteristics. Sensitivity analyses explored possible effects of differences in risk between groups and alternative outcome measures.
Main outcome measures: Composite perinatal outcome measure encompassing âintrapartum related mortality and morbidityâ (intrapartum stillbirth, early neonatal death, neonatal encephalopathy, meconium aspiration syndrome, brachial plexus injury, fractured humerus or clavicle) and neonatal admission within 48 hours for more than 48 hours. Two composite maternal outcome measures capturing intrapartum interventions/adverse maternal outcomes and straightforward birth.
Results: The risk of âintrapartum related mortality and morbidityâ or neonatal admission for more than 48 hours was lower in planned home births than planned OU births [adjusted relative risks (RR) 0.50, 95% CI 0.31â0.81]. Adjustment for clinical risk factors did not materially affect this finding. The direction of effect was reversed for the more restricted outcome measure âintrapartum related mortality and morbidityâ (RR adjusted for parity 1.92, 95% CI 0.97â3.80). Maternal interventions were lower in planned home births.
Conclusions: The babies of âhigher riskâ women who plan birth in an OU appear more likely to be admitted to neonatal care than those whose mothers plan birth at home, but it is unclear if this reflects a real difference in morbidity. Rates of intrapartum related morbidity and mortality did not differ statistically significantly between settings at the 5% level but a larger study would be required to rule out a clinically important difference between the groups
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 âantisocialâ 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
Decoupling algorithms from schedules for easy optimization of image processing pipelines
Using existing programming tools, writing high-performance image processing code requires sacrificing readability, portability, and modularity. We argue that this is a consequence of conflating what computations define the algorithm, with decisions about storage and the order of computation. We refer to these latter two concerns as the schedule, including choices of tiling, fusion, recomputation vs. storage, vectorization, and parallelism.
We propose a representation for feed-forward imaging pipelines that separates the algorithm from its schedule, enabling high-performance without sacrificing code clarity. This decoupling simplifies the algorithm specification: images and intermediate buffers become functions over an infinite integer domain, with no explicit storage or boundary conditions. Imaging pipelines are compositions of functions. Programmers separately specify scheduling strategies for the various functions composing the algorithm, which allows them to efficiently explore different optimizations without changing the algorithmic code.
We demonstrate the power of this representation by expressing a range of recent image processing applications in an embedded domain specific language called Halide, and compiling them for ARM, x86, and GPUs. Our compiler targets SIMD units, multiple cores, and complex memory hierarchies. We demonstrate that it can handle algorithms such as a camera raw pipeline, the bilateral grid, fast local Laplacian filtering, and image segmentation. The algorithms expressed in our language are both shorter and faster than state-of-the-art implementations.National Science Foundation (U.S.) (Grant 0964004)National Science Foundation (U.S.) (Grant 0964218)National Science Foundation (U.S.) (Grant 0832997)United States. Dept. of Energy (Award DE-SC0005288)Cognex CorporationAdobe System
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