Magnetic Field Decay and Period Evolution of Anomalous X-Ray Pulsars in the Context of Quark Stars

We discuss a model wherein soft gamma-ray repeaters (SGRs), anomalous X-ray pulsars (AXPs), and radio quiet isolated neutron stars (RQINSs) are all compact objects exhibiting superconductivity, namely color-flavor locked quark stars. In particular we calculate the magnetic field decay due to the expulsion of spin-induced vortices from the star's superfluid-superconducting interior, and the resultant spin-down rate. We find that, for initial parameters characteristic of AXPs/SGRs ($10^{13}<B<10^{14}~\rm{G}$; $3<P<12~\rm{s}$), the magnetic field strengths and periods remain unchanged within a factor of two for timescales of the order of $5\times 10^{5} - 5\times 10^{7}~\rm{yrs}$ given a quark star of radius $10~\rm{km}$. Within these timescales, we show that the observed period clustering in RQINSs can be explained by compactness, as well as calculate how the magnetic field and period evolve in a manner concurrent with RQINS observations.Comment: 4 pages, 4 figures, accepted to ApJ Letter

Does the engagement of clinicians and organisations in research improve healthcare performance: a three-stage review

Objective: There is a widely held assumption that engagement by clinicians and healthcare organisations in research improves healthcare performance at various levels, but little direct empirical evidence has previously been collated. The objective of this study was to address the question: Does research engagement (by clinicians and organizations) improve healthcare performance? Methods: An hourglass-shaped review was developed, consisting of three stages: (1) a planning and mapping stage; (2) a focused review concentrating on the core question of whether or not research engagement improves healthcare performance; and (3) a wider (but less systematic) review of papers identified during the two earlier stages, focusing on mechanisms. Results: Of the 33 papers included in the focused review, 28 identified improvements in health services performance. Seven out of these papers reported some improvement in health outcomes, with others reporting improved processes of care. The wider review demonstrated that mechanisms such as collaborative and action research can encourage some progress along the pathway from research engagement towards improved healthcare performance. Organisations that have deliberately integrated the research function into organisational structures demonstrate how research engagement can, among other factors, contribute to improved healthcare performance. Conclusions: Current evidence suggests that there is an association between the engagement of individuals and healthcare organisations in research and improvements in healthcare performance. The mechanisms through which research engagement might improve healthcare performance overlap and rarely act in isolation, and their effectiveness often depends on the context in which they operate. Strengths and limitations of this study • This review brings together for the first time a diverse body of literature addressing whether engaging clinicians and healthcare organisations in research is the likely to improve healthcare performance • It also explores the mechanisms through which improvement is achieved to try and understand how any improvements might come about • However, it relies on the quality and coverage of the existing literature • It is an extremely complex topic, but nonetheless one worthy of further exploration, particularly given the pressure to justify research spending in healthcare systems, and to encourage its implementation.UK National Institute for Health Research (NIHR) Service Delivery and Organisation (SDO) programme ( project number HS&DR- 10/1012/09

Simulation de la propagation et du déferlement d’une vague et de l’inondation d’unrèclif 2D: évaluation comparative des codes numérique pour la modélisation des tsunamis

In the framework of the French research project TANDEM dedicated to tsunami modelling, a series of benchmarks has been set up, addressing the various stages of a tsunami event: generation, propagation, run-up and inundation. We present here the results of five codes, involving both depth-averaged Boussinesq and fully 3D Navier-Stokes equations, aimed at being applicable to tsunami modelling. The codes are evaluated on a flow involving propagation, run-up, overtopping and reflection of the waves on two-dimensional reefs, and compared with the experimental data produced from a set of laboratory experiments carried out at the O.H. Hinsdale Wave Research Laboratory, Oregon State University (OSU, see Roeber et al., 2010 and Roeber and Chung, 2012).Dans le cadre du projet de recherche français TANDEM dédié à la modélisation de tsunamis, une série de tests a été mise enplace concernant les différentes étapes d'un tsunami : la génération, la propagation et l'inondation. Les résultats obtenus par cinq codessont présentés ici. Chacun d'eux utilise les équations de Boussinesq moyennées sur la profondeur et les équations de Naver-Stokes entrois dimensions adaptées à la modélisation de tsunamis. Ces codes sont évalués sur un écoulement impliquant la propagation, lasubmersion, et la réflexion des vagues sur un récif en deux dimensions. Une comparaison est effectuée à partir de données expérimentalesprovenant du laboratoire d'Hinsdale (O.H Hinsdale Wave Research Laboratory, Oregon State University, OSU, voir Roeber et al.,2010 etRoeber et Chung, 2012)

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes