Phosphorus deposition on a three-way catalyst under accelerated ageing conditions

Degradation of catalyst performance with time is described as ageing. There are two significant ageing mechanisms: poisoning and sintering. Experimental data on ageing have been obtained on an engine test bed using a specially designed catalyst core holder; the catalyst samples were subjected to different accelerated ageing regimes and durations. The ageing regimes were as follows: low temperature dosed (mainly poisoning); high temperature not dosed (mainly sintering); high temperature dosed (both sintering and poisoning). The experiments provided a series of samples from which the spatial and time dependences of the poisoning have been found. Portions of the samples were subjected to X-ray fluorescence analysis after ageing. A combined model of poisoning and sintering was developed and incorporated into a computational fluid dynamics model. This combined model can predict the level of deactivation as a function of length along the catalyst and as a function of time. Agreement between measured poison accumulation and predictions was achieved by tuning the sintering parameter. </jats:p

Reflections about experiences of compassionate care from award winning undergraduate nurses – What, so what … now what?

BackgroundFrom 2007 until 2012 Edinburgh Napier University’s School of Nursing Midwifery and Social Care in conjunction with NHS Lothian, collaborated on a programme of action research entitled, the Leadership in Compassionate Care Programme. One strand of this research focused on learning and teaching about compassionate care within the undergraduate curriculum. This debate article focuses on the care issues raised by two award winning nursing students who reflected on the development of their compassionate caring skills during their three year Bachelor of Nursing programme.DiscussionThe reflective accounts debate the following issues related to compassionate care; Personal drivers supporting the provision of compassionate care, Challenging and influencing care practices, Providing relationship centred care and, Living with what can’t be achieved. Throughout the debate a model of compassionate care developed from the Leadership in Compassionate Care Programme is used to reflect on key practice issues and provide a framework for practice development.ConclusionThe care issues presented in this paper identify a need to support students in healthcare to; Develop strategies in questioning care practices which do not meet expectations of compassionate care; undertake focussed reflective activities where each student can explore personal drivers, values and perspectives of compassion; actively connect learning in practice with theory in university, enable development in compassionate caring and strategies that support self-compassion; facilitate an understanding and development of emotional intelligence supporting development of resilience

Chasing the identification of ASCA Galactic Objects (ChIcAGO): An X-ray survey of unidentified sources in the galactic plane. I : Source sample and initial results

We present the Chasing the Identification of ASCA Galactic Objects (ChIcAGO) survey, which is designed to identify the unknown X-ray sources discovered during the ASCA Galactic Plane Survey (AGPS). Little is known about most of the AGPS sources, especially those that emit primarily in hard X-rays (2-10 keV) within the Fx 10-13 to 10-11 erg cm -2 s-1 X-ray flux range. In ChIcAGO, the subarcsecond localization capabilities of Chandra have been combined with a detailed multiwavelength follow-up program, with the ultimate goal of classifying the >100 unidentified sources in the AGPS. Overall to date, 93 unidentified AGPS sources have been observed with Chandra as part of the ChIcAGO survey. A total of 253 X-ray point sources have been detected in these Chandra observations within 3′ of the original ASCA positions. We have identified infrared and optical counterparts to the majority of these sources, using both new observations and catalogs from existing Galactic plane surveys. X-ray and infrared population statistics for the X-ray point sources detected in the Chandra observations reveal that the primary populations of Galactic plane X-ray sources that emit in the Fx 10-13 to 10-11 erg cm -2 s-1 flux range are active stellar coronae, massive stars with strong stellar winds that are possibly in colliding wind binaries, X-ray binaries, and magnetars. There is also another primary population that is still unidentified but, on the basis of its X-ray and infrared properties, likely comprises partly Galactic sources and partly active galactic nuclei.Peer reviewedSubmitted Versio

Elicitation of expert prior opinion:application to the MYPAN trial in childhood polyarteritis nodosa

Objectives Definitive sample sizes for clinical trials in rare diseases are usually infeasible. Bayesian methodology can be used to maximise what is learnt from clinical trials in these circumstances. We elicited expert prior opinion for a future Bayesian randomised controlled trial for a rare inflammatory paediatric disease, polyarteritis nodosa (MYPAN, Mycophenolate mofetil for polyarteritis nodosa). Methods A Bayesian prior elicitation meeting was convened. Opinion was sought on the probability that a patient in the MYPAN trial treated with cyclophosphamide would achieve disease remission within 6-months, and on the relative efficacies of mycophenolate mofetil and cyclophosphamide. Expert opinion was combined with previously unseen data from a recently completed randomised controlled trial in ANCA associated vasculitis. Results A pan-European group of fifteen experts participated in the elicitation meeting. Consensus expert prior opinion was that the most likely rates of disease remission within 6 months on cyclophosphamide or mycophenolate mofetil were 74% and 71%, respectively. This prior opinion will now be taken forward and will be modified to formulate a Bayesian posterior opinion once the MYPAN trial data from 40 patients randomised 1:1 to either CYC or MMF become available. Conclusions We suggest that the methodological template we propose could be applied to trial design for other rare diseases