63 research outputs found
Radio Aurora Explorer: Mission science and radar system
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95507/1/rds5936.pd
Initial GPS scintillation results from CASES receiver at South Pole, Antarctica
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94940/1/rds6025.pd
Quasiparticle interfacial level alignment of highly hybridized frontier levels: HO on TiO(110)
Knowledge of the frontier levels' alignment prior to photo-irradiation is
necessary to achieve a complete quantitative description of HO
photocatalysis on TiO(110). Although HO on rutile TiO(110) has been
thoroughly studied both experimentally and theoretically, a quantitative value
for the energy of the highest HO occupied levels is still lacking. For
experiment, this is due to the HO levels being obscured by hybridization
with TiO(110) levels in the difference spectra obtained via ultraviolet
photoemission spectroscopy (UPS). For theory, this is due to inherent
difficulties in properly describing many-body effects at the
HO-TiO(110) interface. Using the projected density of states (DOS) from
state-of-the-art quasiparticle (QP) , we disentangle the adsorbate and
surface contributions to the complex UPS spectra of HO on TiO(110). We
perform this separation as a function of HO coverage and dissociation on
stoichiometric and reduced surfaces. Due to hybridization with the TiO(110)
surface, the HO 3a and 1b levels are broadened into several peaks
between 5 and 1 eV below the TiO(110) valence band maximum (VBM). These
peaks have both intermolecular and interfacial bonding and antibonding
character. We find the highest occupied levels of HO adsorbed intact and
dissociated on stoichiometric TiO(110) are 1.1 and 0.9 eV below the VBM. We
also find a similar energy of 1.1 eV for the highest occupied levels of HO
when adsorbed dissociatively on a bridging O vacancy of the reduced surface. In
both cases, these energies are significantly higher (by 0.6 to 2.6 eV) than
those estimated from UPS difference spectra, which are inconclusive in this
energy region. Finally, we apply self-consistent QP (scQP1) to obtain
the ionization potential of the HO-TiO(110) interface.Comment: 12 pages, 12 figures, 1 tabl
Development, implementation and evaluation of an early warning system improvement programme for children in hospital : the PUMA mixed-methods study
Background:
The Paediatric early warning system Utilisation and Morbidity Avoidance (PUMA) study was commissioned to develop, implement and evaluate a paediatric track-and-trigger tool for widespread adoption. Following findings from three systematic reviews, revised aims focused on implementation of a whole-systems improvement programme.
Objectives:
(1) Identify, through systematic review, the following: evidence for core components of effective paediatric track-and-trigger tools and paediatric early warning systems, and contextual factors consequential for paediatric track-and-trigger tool and early warning system effectiveness. (2) Develop and implement an evidence-based paediatric early warning system improvement programme (i.e. the PUMA programme). (3) Evaluate the effectiveness of the PUMA programme by examining clinical practice and core outcomes trends. (4) Identify ingredients of successful implementation of the PUMA programme.
Review methods:
The quantitative reviews addressed the following two questions: how well validated are existing paediatric track-and-trigger tools and their component parts for predicting inpatient deterioration? How effective are paediatric early warning systems (with or without a tool) at reducing mortality and critical events? The qualitative review addressed the following question: what sociomaterial and contextual factors are associated with successful or unsuccessful paediatric early warning systems (with or without tools)?
Design:
Interrupted time series and ethnographic case studies were used to evaluate the PUMA programme. Qualitative methods were deployed in a process evaluation.
Setting:
The study was set in two district general and two tertiary children’s hospitals.
Intervention:
The PUMA programme is a paediatric early warning system improvement programme designed to harness local expertise to implement contextually appropriate interventions.
Main outcome measures:
The primary outcome was a composite metric, representing children who experienced one of the following in 1 month: mortality, cardiac arrest, respiratory arrest, unplanned admission to a paediatric intensive care unit or unplanned admission to a high-dependency unit. Paediatric early warning system changes were assessed through ethnographic ward case studies.
Results:
The reviews showed limited effectiveness of paediatric track-and-trigger tools in isolation, and multiple failure points in paediatric early warning systems. All sites made paediatric early warning system changes; some of the clearer quantitative findings appeared to relate to qualitative observations. Systems changed in response to wider contextual factors.
Limitations:
Low event rates made quantitative outcome measures challenging. Implementation was not a one-shot event, creating challenges for the interrupted time series in conceptualising ‘implementation’ and ‘post-intervention’ periods.
Conclusions:
Detecting and acting on deterioration in the acute hospital setting requires a whole-systems approach. The PUMA programme offers a framework to support ongoing system-improvement work; the approach could be used more widely. Organisational-level system change can affect clinical outcomes positively. Alternative outcome measures are required for research and quality improvement.
Future work:
The following further research is recommended: a consensus study to identify upstream indicators of paediatric early warning system performance; an evaluation of OUTCOME approach in other clinical areas; an evaluation of supernumerary nurse co-ordinator role; and an evaluation of mandated system improvement.
Study registration:
This study is registered as PROSPERO CRD42015015326
Theoretical studies of proton-coupled electron transfer: Models and concepts relevant to bioenergetics
Monitoring of the ionosphere TEC variations during the 17th August 1999 Izmit earthquake using GPS data
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