987 research outputs found
TRial to Assess Implementation of New research in a primary care Setting (TRAINS): study protocol for a pragmatic cluster randomised controlled trial of an educational intervention to promote asthma prescription uptake in general practitioner practices
Background
There is a marked increase in unscheduled care visits in school-aged children with asthma after returning to school in September. This is potentially associated with children not taking their asthma preventer medication during the school summer holidays. A cluster randomised controlled trial (PLEASANT) was undertaken with 1279 school-age children in 141 general practices (71 on intervention and 70 on control) in England and Wales. It found that a simple letter sent from the family doctor during the school holidays to a parent with a child with asthma, informing them of the importance of taking asthma preventer medication during the summer relatively increased prescriptions by 30% in August and reduced medical contacts in the period September to December. Also, it is estimated there was a cost-saving of £36.07 per patient over the year. We aim to conduct a randomised trial to assess if informing GP practices of an evidence-based intervention improves the implementation of that intervention.
Methods/design
The TRAINS study—TRial to Assess Implementation of New research in a primary care Setting—is a pragmatic cluster randomised implementation trial using routine data. A total of 1389 general practitioner (GP) practices in England will be included into the trial; 694 GP practices will be randomised to the intervention group and 695 control group of usual care. The Clinical Practice Research Datalink (CPRD) will send the intervention and obtain all data for the study, including prescription and primary care contacts data. The intervention will be sent in June 2021 by postal and email to the asthma lead and/or practice manager. The intervention is a letter to GPs informing them of the PLEASANT study findings with recommendations. It will come with an information leaflet about PLEASANT and a suggested reminder letter and SMS text template.
Discussion
The trial will assess if informing GP practices of the PLEASANT trial results will increase prescription uptake before the start of the school year. The hope is that the intervention will increase the implementation of PLEASANT work and then increase prescription uptake during the summer holiday prior to the start of school
\u3cem\u3eIn Situ\u3c/em\u3e Nanomechanical Testing in Focused Ion Beam and Scanning Electron Microscopes
The recent interest in size-dependent deformation of micro- and nanoscale materials has paralleled both technological miniaturization and advancements in imaging and small-scale mechanical testing methods. Here we describe a quantitative in situ nanomechanical testing approach adapted to a dualbeam focused ion beam and scanning electron microscope. A transducer based on a three-plate capacitor system is used for high-fidelity force and displacement measurements. Specimen manipulation, transfer, and alignment are performed using a manipulator, independently controlled positioners, and the focused ion beam. Gripping of specimens is achieved using electron-beam assisted Pt-organic deposition. Local strain measurements are obtained using digital image correlation of electron images taken during testing. Examples showing results for tensile testing of single-crystalline metallic nanowires and compression of nanoporous Au pillars will be presented in the context of size effects on mechanical behavior and highlight some of the challenges of conducting nanomechanical testing in vacuum environments
Molecular spintronics: Coherent spin transfer in coupled quantum dots
Time-resolved Faraday rotation has recently demonstrated coherent transfer of
electron spin between quantum dots coupled by conjugated molecules. Using a
transfer Hamiltonian ansatz for the coupled quantum dots, we calculate the
Faraday rotation signal as a function of the probe frequency in a pump-probe
setup using neutral quantum dots. Additionally, we study the signal of one
spin-polarized excess electron in the coupled dots. We show that, in both
cases, the Faraday rotation angle is determined by the spin transfer
probabilities and the Heisenberg spin exchange energy. By comparison of our
results with experimental data, we find that the transfer matrix element for
electrons in the conduction band is of order 0.08 eV and the spin transfer
probabilities are of order 10%.Comment: 13 pages, 6 figures; minor change
Large rivers and orogens: the evolution of the Yarlung Tsangpo–Irrawaddy system and the eastern Himalayan syntaxis
The eastern Himalayan syntaxis has experienced some of the highest rates of deformation and erosion in the orogen during the Late Cenozoic, and the Yarlung Tsangpo, Brahmaputra, Irrawaddy, Salween, and Mekong rivers are the key erosional systems in that region. The Yarlung Tsangpo drains southern Tibet and the deep Siang River gorge through the eastern Himalayan syntaxis before joining the Brahmaputra in northeastern India. It has been proposed that the Yarlung Tsangpo drained into other large rivers of southern Asia, such as the Irrawaddy, Salween and Red River. We have used uranium/lead dating and hafnium measurements of detrital zircons from Cenozoic sedimentary deposits in Central Myanmar to demonstrate that the Yarlung Tsangpo formerly drained into the Irrawaddy River in Myanmar through the eastern syntaxis, and that this ancient river system was established by (at least) the Middle–Late Eocene. The Yarlung Tsangpo–Irrawaddy river disconnected in the Early Miocene driven by increased deformation in the eastern syntaxis and headward erosion by tributaries of the Brahmaputra. Our results highlight the significance of the sedimentary record of large orogen-parallel rivers and provide key chronological constraints on landscape evolution during the Early Miocene phase of the Himalayan orogeny
Moisture susceptibility of high and low compaction dry process crumb rubber modified asphalt mixtures
The field performance of dry process crumb rubber-modified (CRM) asphalt mixtures has been reported to be inconsistent with stripping and premature cracking on the surfacing. One of the concerns is that, because achieving field compaction of CRM material is difficult due to the inherent resilient nature of the rubber particle, nonuniform field compaction may lead to a deficient bond between rubber and bitumen. To assess the influence of compaction, a series of CRM and control mixtures was produced and compacted at two levels: 4% (low, optimum laboratory compaction) and 8% (high, field experience) air void content. The long-term durability, in regard to moisture susceptibility of the mixtures, was assessed by conducting repeated moisture conditioning cycles. Mechanical properties (stiffness, fatigue, and resistance to permanent deformation) were determined in the Nottingham Asphalt Tester. Results indicated that compared with conventional mixtures, the CRM mixtures, regardless of compaction effort, are more susceptible to moisture with the degree of susceptibility primarily depending on the amount of rubber in the mixture, rather than the difference in compaction. This behavior is different from that of conventional mixtures in which, as expected, poorly compacted mixtures were found to be more susceptible to moisture than were well-compacted mixtures
Magnetic enhancement of CoZnFeO spinel oxide by mechanical milling
We report the magnetic properties of mechanically milled
CoZnFeO spinel oxide. After 24 hours milling of the
bulk sample, the XRD spectra show nanostructure with average particle size
20 nm. The as milled sample shows an enhancement in magnetization and
ordering temperature compared to the bulk sample. If the as milled sample is
annealed at different temperatures for the same duration, recrystallization
process occurs and approaches to the bulk structure on increasing the annealing
temperatures. The magnetization of the annealed samples first increases and
then decreases. At higher annealing temperature ( 1000C) the system
shows two coexisting magnetic phases {\it i.e.}, spin glass state and
ferrimagnetic state, similar to the as prepared bulk sample. The room
temperature M\"{o}ssbauer spectra of the as milled sample, annealed at
300C for different durations (upto 575 hours), suggest that the observed
change in magnetic behaviour is strongly related with cations redistribution
between tetrahedral (A) and octahedral (O) sites in the spinel structure. Apart
from the cation redistribution, we suggest that the enhancement of
magnetization and ordering temperature is related with the reduction of B site
spin canting and increase of strain induced anisotropic energy during
mechanical milling.Comment: 14 pages LaTeX, 10 ps figure
Integrable Open Spin Chains in Defect Conformal Field Theory
We demonstrate that the one-loop dilatation generator for the scalar sector
of a certain perturbation of N=4 Super Yang-Mills with fundamentals is the
Hamiltonian of an integrable spin chain with open boundary conditions. The
theory is a supersymmetric defect conformal field theory (dCFT) with the
fundamentals in hypermultiplets confined to a codimension one defect. We obtain
a K-matrix satisfying a suitably generalized form of the boundary Yang-Baxter
equation, study the Bethe ansatz equations and demonstrate how Dirichlet and
Neumann boundary conditions arise in field theory, and match to existing
results in the plane wave limit.Comment: 26 pages, LaTeX. v2: references added, typos correcte
Local densities, distribution functions, and wave function correlations for spatially resolved shot noise at nanocontacts
We consider a current-carrying, phase-coherent multi-probe conductor to which
a small tunneling contact is attached. We treat the conductor and the tunneling
contact as a phase-coherent entity and use a Green's function formulation of
the scattering approach. We show that the average current and the current
fluctuations at the tunneling contact are determined by an effective local
non-equilibrium distribution function. This function characterizes the
distribution of charge-carriers (or quasi-particles) inside the conductor. It
is an exact quantum-mechanical expression and contains the phase-coherence of
the particles via local partial densities of states, called injectivities. The
distribution function is analyzed for different systems in the zero-temperature
limit as well as at finite temperature. Furthermore, we investigate in detail
the correlations of the currents measured at two different contacts of a
four-probe sample, where two of the probes are only weakly coupled contacts. In
particular, we show that the correlations of the currents are at
zero-temperature given by spatially non-diagonal injectivities and
emissivities. These non-diagonal densities are sensitive to correlations of
wave functions and the phase of the wave functions. We consider ballistic
conductors and metallic diffusive conductors. We also analyze the Aharonov-Bohm
oscillations in the shot noise correlations of a conductor which in the absence
of the nano-contacts exhibits no flux-sensitivity in the conductance.Comment: 17 pages, 8 figure
On the origin of M81 group extended dust emission
Galactic cirrus emission at far-infrared wavelengths affects many extragalactic observations. Separating this emission from that associated with extragalactic objects is both important and difficult. In this paper we discuss a particular case, the M81 group, and the identification of diffuse structures prominent in the infrared, but also detected at optical wavelengths. The origin of these structures has previously been controversial, ranging from them being the result of a past interaction between M81 and M82 or due to more local Galactic emission. We show that over an order of a few arcmin scales, the far-infrared (Herschel 250 mu m) emission correlates spatially very well with a particular narrow-velocity (2-3 km s(-1)) component of the Galactic HI. We find no evidence that any of the far-infrared emission associated with these features actually originates in the M81 group. Thus we infer that the associated diffuse optical emission must be due to galactic light-back scattered off dust in our galaxy. Ultraviolet observations pick out young stellar associations around M81, but no detectable far-infrared emission. We consider in detail one of the Galactic cirrus features, finding that the far-infrared HI relation breaks down below arcmin scales and that at smaller scales there can be quite large dust-temperature variation
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