Magnetic susceptibility, transport and heat capacity measurements for single-crystal NaxCoO2 (x = 0.71) are reported. A transition to a spin density wave (SDW) state at Tmag = 22 K is observable in all measurements, except χac data in which a cusp is observed at 4 K and attributed to a low temperature glassy phase. M(H) loops are hysteretic below 15 K. Both the SDW transition and low temperature hysteresis are only visible along the c-axis. The system also exhibits a substantial positive magnetoresistance below this temperature. Calculations of the electronic heat capacity γ above and below Tmag and the size of the jump in C indicate that the onset of the SDW brings about the opening of a gap and the removal of part of the Fermi surface. Reduced in-plane electron–electron scattering counteracts the loss of carriers below the transition and as a result we see a net reduction in resistivity below Tmag. Sodium ordering transitions at higher temperatures are observable as peaks in the heat capacity with a corresponding increase in resistivity.

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The characteristics of a new ferroelectric measurement system at the European Synchrotron Radiation Facility are presented. The electric-field-induced phase transitions of Pb(Mg(1/3)Nb(2/3))O(3)-xPbTiO(3) are determined via in situ measurements of electric polarization within the synchrotron diffraction beamline. Real-time data collection methods on single-crystal samples are employed as a function of frequency to determine the microstructural origin of piezoelectric effects within these materials, probing the dynamic ferroelectric response.

Patients with implanted orthopaedic devices represent a growing number of subjects undergoing magnetic resonance imaging (MRI) scans each year. MRI safety labelling is required for all implants under the EU Medical Device Regulations to ensure regulatory compliance, with each device assessed through standardised testing procedures. In this paper, we employ parametric studies to assess a range of clinically relevant factors that cause tissue heating, performing simulations with both radiofrequency (RF) and gradient coil (GC) switching fields, the latter of which is often overlooked in the literature. A series of worst case scenarios for both types of excitation field are discussed. In the case of GC fields large volume implants and large plate areas with the field oriented perpendicular to the plane cause the highest heating levels, along with sequences with high rates of field switching. Implant heating from RF fields is driven primarily from the antenna effect, with thin, linear implants of resonant length resulting in the highest temperature rises. In this work, we show that simplifications may be made to the field sequence and device geometry without significantly comprising the accuracy of the simulation results, opening up the possibility for generic estimates of the implant heating for orthopaedic device manufacturers and opportunities to simplify the safety compliance process.

In this article we test whether metrics of online attention describing research can provide information on research quality and societal impact that is not found in citation data alone. Our approach is to set up a traditional model in which the true quality or impact of a university department is determined by a panel of experts, but a citation metric is regarded as a reasonable proxy. However, the model assumes that the information contained in the scores provided by an expert panel exceeds that contained in a citation metric (HEFCE, 2015). Finally, we extend this model by including altmetric data to see if it adds information about a department's performance that cannot be gleaned from citations alone. We find the presence of altmetric data for the cited underpinning research to be highly correlated with peer review scores for societal impact. Conversely, no such connection was seen with the assessment of research quality. Our findings therefore suggest altmetric data could be useful as an aid to assessing impact. Data SourcesThe analysis was restricted to main panel B of the submissions, which relates to mathematics, engineering, and the physical sciences (see Table 1). Within this subject grouping, 48,815 of the submitted 49,317 research outputs were journal articles, allowing a near complete mapping of bibliometric indicators to REF scores. The research activity in this panel is subdivided into nine separate topics; however, for the purpose of this work, three of the engineering units of assessments (UOAs) were combined, as they could all be labeled as "applied engineering." The creation of this agglomerated group meant that the number of submitted outputs across the subject areas were somewhat equalized

A variable frequency ferroelectric polarisation measurement system has been designed and built at the UK's Diamond Light Source. The electric field induced phase transitions in Pb(Zr1−xTix)O3 (PZT) have been used to test the facility via in-situ measurements of electric polarisation and XRD. Stroboscopic and real time data collection methods on polycrystalline samples were employed as a function of frequency to determine the dynamic ferroelectric response. The system has been shown to deliver XRD patterns of good statistical quality measured over 40 points of a ferroelectric PE loop. The system is now available on station I11 as a user facility at the Diamond Light Source.