507 research outputs found
Novel muon imaging techniques
Owing to the high penetrating power of high-energy cosmic ray muons, muon imaging techniques can be used to image large bulky objects, especially objects with heavy shielding. Muon imaging systems work just like CT scanners in the medical imaging field—that is, they can reveal information inside of a target. There are two forms of muon imaging techniques: muon absorption imaging and muon multiple scattering imaging. The former is based on the flux attenuation of muons, and the latter is based on the multiple scattering of muons in matter. The muon absorption imaging technique is capable of imaging very large objects such as volcanoes and large buildings, and also smaller objects like spent fuel casks; the muon multiple scattering imaging technique is best suited to inspect smaller objects such as nuclear waste containers. Muon imaging techniques can be applied in a broad variety of fields, i.e. from measuring the magma thickness of volcanoes to searching for secret cavities in pyramids, and from monitoring the borders of countries checking for special nuclear materials to monitoring the spent fuel casks for nuclear safeguards applications. In this paper, the principles of muon imaging are reviewed. Image reconstruction algorithms such as Filtered Back Projection and Maximum Likelihood Expectation Maximization are discussed. The capability of muon imaging techniques is demonstrated through a Geant4 simulation study for imaging a nuclear spent fuel cask
The influence of maternal health factors including multimorbidity on child oral health:A scoping review and evidence gap map protocol
Read the latest article version by Faith Campbell, Scott McGregor, Louise Marryat, Ryan Stewart, Jan Clarkson, Heather Cassie at Wellcome Open Researc
The influence of maternal health factors including multimorbidity on child oral health:A scoping review and evidence gap map protocol
Read the latest article version by Faith Campbell, Scott McGregor, Louise Marryat, Ryan Stewart, Jan Clarkson, Heather Cassie at Wellcome Open Researc
Carbon monoxide poisoning: novel magnetic resonance imaging pattern in the acute setting
The presentation of carbon monoxide (CO) poisoning is non-specific and highly variable. The diagnosis is made when a compatible history and examination occur in a patient with elevated carboxyhaemoglobin levels. The severity of intoxication is difficult to assess accurately based on laboratory markers alone. Magnetic resonance imaging (MRI) has been shown to have superior sensitivity to computed tomography for the detection of abnormalities post CO poisoning. We report a novel imaging pattern on MRI undertaken in the acute setting in a patient with CO intoxication. We also discuss the management and follow up of patients with CO poisoning
Carbon monoxide poisoning: Novel magnetic resonance imaging pattern in the acute setting
The presentation of carbon monoxide (CO) poisoning is non-specific and highly variable. The diagnosis is made when a compatible history and examination occur in a patient with elevated carboxyhaemoglobin levels. The severity of intoxication is difficult to assess accurately based on laboratory markers alone. Magnetic resonance imaging (MRI) has been shown to have superior sensitivity to computed tomography for the detection of abnormalities post CO poisoning. We report a novel imaging pattern on MRI undertaken in the acute setting in a patient with CO intoxication. We also discuss the management and follow up of patients with CO poisoning
Atomic-scale control of magnetic anisotropy via novel spin-orbit coupling effect in La2/3Sr1/3MnO3/SrIrO3 superlattices
Magnetic anisotropy (MA) is one of the most important material properties for
modern spintronic devices. Conventional manipulation of the intrinsic MA, i.e.
magnetocrystalline anisotropy (MCA), typically depends upon crystal symmetry.
Extrinsic control over the MA is usually achieved by introducing shape
anisotropy or exchange bias from another magnetically ordered material. Here we
demonstrate a pathway to manipulate MA of 3d transition metal oxides (TMOs) by
digitally inserting non-magnetic 5d TMOs with pronounced spin-orbit coupling
(SOC). High quality superlattices comprised of ferromagnetic La2/3Sr1/3MnO3
(LSMO) and paramagnetic SrIrO3 (SIO) are synthesized with the precise control
of thickness at atomic scale. Magnetic easy axis reorientation is observed by
controlling the dimensionality of SIO, mediated through the emergence of a
novel spin-orbit state within the nominally paramagnetic SIO.Comment: Proceedings of the National Academy of Sciences, May 201
Cost-effectiveness of child caries management: a randomised controlled trial (FiCTION trial)
Background: A three-arm parallel group, randomised controlled trial set in general dental practices in England, Scotland, and Wales was undertaken to evaluate three strategies to manage dental caries in primary teeth. Children, with at least one primary molar with caries into dentine, were randomised to receive Conventional with best practice prevention (C + P), Biological with best practice prevention (B + P), or best practice Prevention Alone (PA). Methods: Data on costs were collected via case report forms completed by clinical staff at every visit. The coprimary outcomes were incidence of, and number of episodes of, dental pain and/or infection avoided. The three strategies were ranked in order of mean cost and a more costly strategy was compared with a less costly strategy in terms of incremental cost-effectiveness. Costs and outcomes were discounted at 3.5%. Results: A total of 1144 children were randomised with data on 1058 children (C + P n = 352, B + P n = 352, PA n = 354) used in the analysis. On average, it costs £230 to manage dental caries in primary teeth over a period of up to 36 months. Managing children in PA was, on average, £19 (97.5% CI: -£18 to £55) less costly than managing those in B + P. In terms of effectiveness, on average, there were fewer incidences of, (− 0.06; 97.5% CI: − 0.14 to 0.02) and fewer episodes of dental pain and/or infection (− 0.14; 97.5% CI: − 0.29 to 0.71) in B + P compared to PA. C + P was unlikely to be considered cost-effective, as it was more costly and less effective than B + P. Conclusions: The mean cost of a child avoiding any dental pain and/or infection (incidence) was £330 and the mean cost per episode of dental pain and/or infection avoided was £130. At these thresholds B + P has the highest probability of being considered cost-effective. Over the willingness to pay thresholds considered, the probability of B + P being considered cost-effective never exceeded 75%. Trial registration: The trial was prospectively registered with the ISRCTN (reference number ISRCTN77044005) on the 26th January 2009 and East of Scotland Research Ethics Committee provided ethical approved (REC reference: 12/ES/0047)
A hydrothermally stable Ytterbium metal-organic framework as a bifunctional solid-acid catalyst for glucose conversion
Yb6(BDC)7(OH)4(H2O)4 contains both bridging hydroxyls and metal-coordinated waters, possessing Brønsted and Lewis acid sites. The material crystallises from water at 200C. Using the solid as a heterogenous catalyst, glucose is converted into 5-hydroxymethylfurfural, via fructose, with a total selectivity of ~70 % after 24 hours at 140 C in water alone: the material is recyclable with no loss of crystallinity
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