2,620 research outputs found
That\u27s My Voice! Participation and Democratic Citizenship in the Early Childhood Classroom
This paper shares a participatory action research study conducted by a team of researchers at a university laboratory school in collaboration with three classroom teachers and 60 preschoolers. The team engaged in this research in order to examine the ways in which school personnel could generate more authentic community service experiences with, rather than simply for, children. Findings illustrate that with the support of adults, children generated ways to address issues, discussed their ideas with adults, reflected on their actions, and understood that their voices were being heard beyond the school community. With this increased participation, young people were able to show and exercise crucial skills and dispositions for democratic citizenship
Effects of standard and fortified ‘Meals-on-wheels’ meals on clinical outcomes of nutritionally at risk elderly
‘Unboxing’ videos: co-construction of the child as cyberflâneur
This paper draws on data from a study of a four-year-old child, Gareth, in his first year of formal schooling in England. The aim of the study was to identify the nature of Gareth's literacy practices across home and school spaces. The focus for this paper is an analysis of one aspect of Gareth's home digital literacy practices: his repeated viewings at home of ‘unboxing’ videos on YouTube. These include videos that feature the unpacking of commercial products. It is argued that the child viewer/reader is co-constructed in these practices as cyberflâneur and that this mode of cultural transmission is a growing feature of online practices for this age group in the twenty-first century. The paper addresses issues concerning young children's online practices and their relationship to material culture before analysing the growth of interest in peer-to-peer textual production and consumption in the digital age
Rapid timing studies of black hole binaries in Optical and X-rays: correlated and non-linear variability
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Enhanced Control of Mercury by Wet Flue Gas Desulfurization Systems -- Site 3 Topical Report
The U.S. Department of Energy and EPRI have co-funded this project to improve the control of mercury emissions from coal-fired power plants equipped with wet flue gas desulfurization (FGD) systems. The project investigated catalytic oxidation of vapor-phase elemental mercury to a form that is more effectively captured in wet FGD systems. If successfully developed, the process could be applicable to over 90,000 MW of utility generating capacity with existing FGD systems and to future FGD installations. Field tests have been conducted to determine whether candidate catalyst materials remain active towards mercury oxidation after extended flue gas exposure. Catalyst life will have a large impact on the cost effectiveness of this potential process. A mobile catalyst test unit has been used to test the activity of four different catalyst materials for a period of up to six months at each of three utility sites. Catalyst testing was completed at the first site, which fires Texas lignite, in December 1998 and at the second test site, which fires a Powder River Basin subbituminous coal in the fall of 1999. Testing at the third site, which fires a medium- to high-sulfur bituminous coal, began in June 2000 and was completed at the end of January 2001. This Topical Reports includes results from Site 3; results from Sites 1 and 2 were reported previously. At Site 3, catalysts were tested in two forms, including powders dispersed in sand bed reactors and in a commercially available form as a coated honeycomb structure. Field testing has been supported by laboratory tests to screen catalysts for activity at specific flue gas compositions, to investigate catalyst deactivation mechanisms and methods for regenerating spent catalysts. Laboratory results related to the Site 3 field effort are also included and discussed in this Topical Report
Orbital and stochastic far-UV variability in the nova-like system V3885 Sgr
Highly time-resolved time-tagged FUSE satellite spectroscopic data are
analysed to establish the far-ultraviolet (FUV) absorption line characteristics
of the nova-like cataclysmic variable binary, V3885 Sgr. We determine the
temporal behaviour of low (Ly_beta, CIII, NIII) and high (SIV, PV, OVI) ion
species, and highlight corresponding orbital phase modulated changes in these
lines. On average the absorption troughs are blueshifted due to a low velocity
disc wind outflow. Very rapid (~ 5 min) fluctuations in the absorption lines
are isolated, which are indicative of stochastic density changes. Doppler
tomograms of the FUV lines are calculated which provide evidence for structures
where a gas stream interacts with the accretion disc. We conclude that the line
depth and velocity changes as a function of orbital phase are consistent with
an asymmetry that has its origin in a line-emitting, localised disc-stream
interaction region.Comment: Accepted for publication in MNRA
Is a definitive trial of prehospital continuous positive airway pressure versus standard oxygen therapy for acute respiratory failure indicated? The ACUTE pilot randomised controlled trial
Objectives To determine the feasibility of a large-scale definitive multicentre trial of prehospital continuous positive airway pressure (CPAP) in acute respiratory failure.
Design A single-centre, open-label, individual patient randomised, controlled, external pilot trial.
Setting A single UK Ambulance Service, between August 2017 and July 2018.
Participants Adults with respiratory distress and peripheral oxygen saturations below British Thoracic Society target levels despite controlled oxygen treatment.
Interventions Patients were randomised to prehospital CPAP (O-Two system) versus standard oxygen therapy in a 1:1 ratio using simple randomisation.
Primary and secondary outcome measures Feasibility outcomes comprised recruitment rate, adherence to allocated treatment, retention and data completeness. The primary clinical outcome was 30-day mortality.
Results 77 patients were enrolled (target 120), including 7 cases with a diagnosis where CPAP could be ineffective or harmful. CPAP was fully delivered in 74% (target 75%). There were no major protocol violations. Full data were available for all key outcomes (targets ≥90%). Overall 30-day mortality was 27.3%. Of these deceased patients, 14/21 (68%) either did not have a respiratory condition or had ceiling of treatment decisions implemented excluding hospital non-invasive ventilation and critical care.
Conclusions Recruitment rate was below target and feasibility was not demonstrated. Limited compliance with CPAP, and difficulty in identifying patients who could benefit from CPAP, indicate that prehospital CPAP is unlikely to materially reduce mortality. A definitive effectiveness trial of CPAP is therefore not recommended.
Trial registration number ISRCTN12048261; Post-results
Rapid optical and X-ray timing observations of GX 339−4: multicomponent optical variability in the low/hard state
A rapid timing analysis of Very Large Telescope (VLT)/ULTRACAM (optical) and RXTE (X-ray) observations of the Galactic black hole binary GX  339− 4 in the low/hard, post-outburst state of 2007 June is presented. The optical light curves in the r ′,  g ′ and u ′ filters show slow (∼20 s) quasi-periodic variability. Upon this is superposed fast flaring activity on times approaching the best time resolution probed (∼50 ms in r ′ and g ′) and with maximum strengths of more than twice the local mean. Power spectral analysis over ∼0.004–10 Hz is presented, and shows that although the average optical variability amplitude is lower than that in X-rays, the peak variability power emerges at a higher Fourier frequency in the optical. Energetically, we measure a large optical versus X-ray flux ratio, higher than that seen on previous occasions when the source was fully jet dominated. Such a large ratio cannot be easily explained with a disc alone. Studying the optical–X-ray cross-spectrum in Fourier space shows a markedly different behaviour above and below ∼0.2 Hz. The peak of the coherence function above this threshold is associated with a short optical time lag with respect to X-rays, also seen as the dominant feature in the time-domain cross-correlation at ≈150 ms. The rms energy spectrum of these fast variations is best described by distinct physical components over the optical and X-ray regimes, and also suggests a maximal irradiated disc fraction of 20 per cent around 5000 Å. If the constant time delay is due to propagation of fluctuations to (or within) the jet, this is the clearest optical evidence to date of the location of this component. The low-frequency quasi-periodic oscillation is seen in the optical but not in X-rays, and is associated with a low coherence. Evidence of reprocessing emerges at the lowest Fourier frequencies, with optical lags at ∼10 s and strong coherence in the blue u ′ filter. Consistent with this, simultaneous optical spectroscopy also shows the Bowen fluorescence blend, though its emission location is unclear. However, canonical disc reprocessing cannot dominate the optical power easily, nor explain the fast variability.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79284/1/j.1365-2966.2010.17083.x.pd
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