Arnold diffusion for a complete family of perturbations

In this work we illustrate the Arnold diffusion in a concrete example — the a priori unstable Hamiltonian system of 2 + 1/2 degrees of freedom H(p, q, I, f, s) = p2/2+ cos q - 1 + I2/2 + h(q, f, s; e) — proving that for any small periodic perturbation of the form h(q, f, s; e) = e cos q (a00 + a10 cosf + a01 cos s) (a10a01 ¿ 0) there is global instability for the action. For the proof we apply a geometrical mechanism based on the so-called scattering map. This work has the following structure: In the first stage, for a more restricted case (I* ~ p/2µ, µ = a10/a01), we use only one scattering map, with a special property: the existence of simple paths of diffusion called highways. Later, in the general case we combine a scattering map with the inner map (inner dynamics) to prove the more general result (the existence of instability for any µ). The bifurcations of the scattering map are also studied as a function of µ. Finally, we give an estimate for the time of diffusion, and we show that this time is primarily the time spent under the scattering map.Peer ReviewedPostprint (published version

Manual on Metric Building Drawing Practice

This manual, prepared by the Working Group of the Subcommittee on Design and Construction of the Interdepartmental Committee on Metric Conversion, has been developed to assist in the preparation of proper construction drawings that are so essential to a smooth transition. This Manual is a basic tool for metric conversion. The first three Parts explain what is involved in this conversion. Part 4 gives a step-by-step procedure for the production of metric drawings; the following Parts will assist, it is hoped, in design decisions and offer help with the actual "translating" of a design approach to metric.Ce manuel, pr\ue9par\ue9 par le Groupe de travail du Sous-comit\ue9 de conception et de construction du Comit\ue9 interminist\ue9riel de conversion m\ue9trique a \ue9t\ue9 \ue9labor\ue9 afin d'assister \ue0 la pr\ue9 paration des dessins de constructions appropri\ue9s qui sont essentiels \ue0 une transition ordonn\ue9e. Ce manuel est un ouvrage de base pour la conversion m\ue9trique. Les trois premi\ue8res parties expliquent ce qui est impliqu\ue9 dans cette conversion. La partie 4 donne une m\ue9thode \ue9tape de production des dessins m\ue9triques; il est souhait\ue9 que les parties suivantes aideront les d\ue9cisions de calcul et pourront offrir de l'aide dans la "traduction" d'une approche au calcul en utilisant le syst\ue8me m\ue9trique.Peer reviewed: NoNRC publication: Ye

Improving the appropriateness of antipsychotic prescribing in nursing homes: a mixed-methods process evaluation of an academic detailing intervention

Abstract Background In 2014, nursing home administration and government officials were facing increasing public and media scrutiny around the variation of antipsychotic medication (APM) prescribing across Ontario nursing homes. In response, policy makers partnered to test an academic detailing (AD) intervention to address appropriate prescribing of APM in nursing homes in a cluster-randomized trial. This mixed-methods study aimed to explore how and why the AD intervention may have resulted in changes in the nursing home context. The objectives were to understand how the intervention was implemented, explore contextual factors associated with implementation, and examine impact of the intervention on prescribing. Methods Administrative data for the primary outcome of the full randomized trial will not be available for a minimum of 1 year. Therefore, this paper reports the findings of a planned, quantitative interim trial analysis assessed mean APM dose and prescribing prevalence at baseline and 3 and 6 months across 40 nursing homes (18 intervention, 22 control). Patient-level administrative data regarding prescribing were analyzed using generalized linear mixed effects regression. Semi-structured interviews were conducted with nursing home staff from the intervention group to explore opinions and experiences of the AD intervention. Interviews were analyzed using the framework method, with constructs from the Consolidated Framework for Implementation Research (CFIR) applied as pre-defined deductive codes. Open coding was applied when emerging themes did not align with CFIR constructs. Qualitative and quantitative findings were triangulated to examine points of divergence to understand how the intervention may work and to identify areas for future opportunities and areas for improvement. Results No significant differences were observed in prescribing outcomes. A total of 22 interviews were conducted, including four academic detailers and 18 nursing home staff. Constructs within the CFIR domains of Outer Setting, Inner Setting, and Characteristics of Individuals presented barriers to antipsychotic prescribing. Intervention Source, Evidence Strength and Quality, and Adaptability explained participant engagement in the AD intervention; nursing homes that exhibited a Tension for Change and Leadership Engagement reported positive changes in processes and communication. Conclusions Participants described their experiences with the intervention against the backdrop of a range of factors that influence APM prescribing in nursing homes that exist at the system, facility, provider, and resident levels. In this context, the perceived credibility and flexibility of the intervention were critical features that explained engagement with and potential impact of the intervention. Development of a common language across the team to enable communication was reported as a proximal outcome that may eventually have an effect on APM prescribing rates. Process evaluations may be useful during early stages of evaluation to understand how the intervention is working and how it might work better. Qualitative results suggest the lack of early changes observed in prescribing may reflect the number of upstream factors that need to change for APM rates to decrease. Trial registration ClinicalTrials.gov, NCT0260405