Mesoscale flux-closure domain formation in single-crystal BaTiO3

Over 60 years ago, Charles Kittel predicted that quadrant domains should spontaneously form in small ferromagnetic platelets. He expected that the direction of magnetization within each quadrant should lie parallel to the platelet surface, minimizing demagnetizing fields,and that magnetic moments should be configured into an overall closed loop, or flux-closure arrangement. Although now a ubiquitous observation in ferromagnets, obvious flux-closure patterns have been somewhat elusive in ferroelectric materials. This is despite the analogous behaviour between these two ferroic subgroups and the recent prediction of dipole closure states by atomistic simulations research. Here we show Piezoresponse Force Microscopy images of mesoscopic dipole closure patterns in free-standing, single-crystal lamellae of BaTiO3. Formation of these patterns is a dynamical process resulting from system relaxation after the BaTiO3 has been poled with a uniform electric field. The flux-closure states are composed of shape conserving 90° stripe domains which minimize disclination stresses

The National Institute for Health Research Hyperacute Stroke Research Centres and the ENCHANTED trial: the impact of enhanced research infrastructure on trial metrics and patient outcomes

Background The English National Institute for Health Research Clinical Research Network first established Hyperacute Stroke Research Centres (HSRCs) in 2010 to support multicentre hyperacute (< 9 h) and complex stroke research. We assessed the impact of this investment on research performance and patient outcomes in a post-hoc analysis of country-specific data from a large multicentre clinical trial. Methods Comparisons of baseline, outcome and trial metric data were made for participants recruited to the alteplase-dose arm of the international Enhanced Control of Hypertension and Thrombolysis Stroke study (ENCHANTED) at National Institute for Health Research Clinical Research Network HSRCs and non-HSRCs between June 2012 and October 2015. Results Among 774 ENCHANTED United Kingdom participants (41% female; mean age 72 years), 502 (64.9%) were recruited from nine HSRCs and 272 (35.1%) from 24 non-HSRCs. HSRCs had higher monthly recruitment rates (median 1.5, interquartile interval 1.4–2.2 vs. 0.7, 0.5–1.3; p = 0.01) and shorter randomisation-to-treatment times (2.6 vs. 3.1 min; p = 0.01) compared to non-HSRCs. HSRC participants were younger and had milder stroke severity, but clinically important between-group differences in 90-day death or disability outcomes remained after adjustment for minimisation criteria and important baseline variables at randomisation, whether defined by ordinal modified Rankin scale score shift (adjusted OR 0.82, 95% CI 0.62–1.08; p = 0.15), scores 2 to 6 (adjusted OR 0.71, 95% CI 0.50–1.01; p = 0.05), or scores 3 to 6 (adjusted OR 0.82, 95% CI 0.57–1.17; p = 0.27). There was no significant difference in symptomatic intracerebral haemorrhage, nor heterogeneity in the comparative treatment effects between low- and standard-dose alteplase by HSRCs or non-HSRCs. Conclusions Infrastructure investment in HSRCs was associated with improved research performance metrics, particularly recruitment and time to treatment with clinically important, though not statistically significant, improvements in patient outcomes

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions

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Measurement of top quark–antiquark pair production in association with a W or Z boson in pp collisions at √s=8 TeV

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Searches for electroweak production of charginos, neutralinos, and sleptons decaying to leptons and W, Z, and Higgs bosons in pp collisions at 8 TeV

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Study of hadronic event-shape variables in multijet final states in pp collisions at √s=7 TeV

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Measurement of prompt J/ψ pair production in pp collisions at √s = 7 Tev

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Observation of the diphoton decay of the Higgs boson and measurement of its properties

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Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at √s=7 TeV

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