758 research outputs found

    Metrics and spectral triples for Dirichlet and resistance forms

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    The article deals with intrinsic metrics, Dirac operators and spectral triples induced by regular Dirichlet and resistance forms. We show, in particular, that if a local resistance form is given and the space is compact in resistance metric, then the intrinsic metric yields a geodesic space. Given a regular Dirichlet form, we consider Dirac operators within the framework of differential 1-forms proposed by Cipriani and Sauvageot, and comment on its spectral properties. If the Dirichlet form admits a carr\'e operator and the generator has discrete spectrum, then we can construct a related spectral triple, and in the compact and strongly local case the associated Connes distance coincides with the intrinsic metric. We finally give a description of the intrinsic metric in terms of vector fields

    A measurement of the neutron electric form factor at very large momentum transfer using polarized electrons scattering from a polarized helium-3 target

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    Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q2 and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized 3He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. GEn was measured to be 0.0242 +/- 0.0020(stat) +/- 0.0061(sys) and 0.0247 +/- 0.0029(stat) +/- 0.0031(sys) at Q2 = 1.7 and 2.5 GeV2, respectively

    The evaluation of a framework for measuring the non-technical ward round skills of final year nursing students: an observational study

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    Background The importance of non-technical skills (NTS) to patient outcomes is increasingly being recognised, however, there is limited research into how such skills can be taught and evaluated in student nurses in relation toward rounds. Objectives This pilot study describes an evaluation of a NTS framework that could potentially be used to measure ward round skills of student nurses. Design and Methods The study used an observational design. Potential key NTS were identified from existing literature and NTS taxonomies. The proposed framework was then used to evaluate whether the identified NTS were evident in a series of ward round simulations that final year general nursing students undertook as part of their training. Finally, the views of a small group of qualified nurse educators, qualified nurses and general nursing students were sought about whether the identified NTS were important and relevant to practice. Results The proposed NTS framework included seven categories: Communication, Decision Making, Situational Awareness, Teamwork and Task Management, Student Initiative and Responsiveness to Patient. All were rated as important and relevant to practice. Conclusion The pilot study suggests that the proposed NTS framework could be used as a means of evaluating student nurse competencies in respect of many non-technical skills required for a successful ward round. Further work is required to establish the validity of the framework in educational settings and to determine the extent to which it is of use in a non-simulated ward round setting

    Effects of a single interprofessional simulation session on medical and nursing students’ attitudes toward interprofessional learning and professional identity: a questionnaire study

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    Background Participation in simulation-based interprofessional education (sim-IPE) may affect students’ attitudes towards interprofessional learning (through gaining experience with others) and their professional identity (by increasing the ‘fit’ of group membership). We examined this in two questionnaire studies involving students from four universities in two areas of the UK. Method Questionnaire data were collected before and after students took part in a sim-IPE session consisting of three acute scenarios. Questionnaires included the Readiness for Interprofessional Learning Scale (RIPLS) and measures of professional identity derived from the social identity theory literature. In Study 1, only identification with Professional Group (doctor or nurse) was measured, while in Study 2 identification with Student Group (medical or nursing student) and the immediate interprofessional Team worked with in the simulation were also measured. Linear mixed effects regression analysis examined the effect of the simulation session, and differences between medical and nursing students, sites and identity measures. Results A total of 194 medical and 266 nursing students completed questionnaires. A five-item subset of RIPLS (RIPLSCore) was used in analysis. In both studies RIPLSCore increased for all groups following participation in sim-IPE, although this was larger for nursing students in Study 1. Nursing students had consistently higher RIPLSCore scores than medical students at one site. Effects of the session on identity varied between sites, and dimensions of identity. Notably, while positive emotions associated with group membership (Ingroup Affect) increased for Student Group, Professional Group and Team, the sense of belonging (Ingroup Ties) and importance (Centrality) of the group increased only for Team. Nursing students had consistently higher identification scores than medical students. Conclusions Participation in a sim-IPE session can improve attitudes towards interprofessional learning. It can also enhance professional identity, particularly as related to emotional aspects of group membership, with possible benefits for wellbeing. Changes in identification with the immediate Team suggest positive psychological consequences of ad hoc Team formation in the workplace. Differences between medical and nursing students suggest their differing opportunities to work with other professions during training may change baseline attitudes and identity. However, a single sim-IPE session can still have an additive effect

    Refractory times for excitable dual state quantum dot laser neurons

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    Excitable photonic systems show promise for ultrafast analog computation, several orders of magnitude faster than biological neurons. Optically injected quantum dot lasers display several excitable mechanisms with dual state quantum lasers recently emerging as true all or none excitable artificial neurons. For use in applications, deterministic triggering is necessary and this has previously been demonstrated in the literature. In this work we analyse the crucially important \emph{refractory time} for this dual state system, which defines the minimum possible time between distinct pulses in any excitable pulse train. Ultrashort times on the order of 1~ns are obtained suggesting potential use where ultrafast analog computing is desired

    Energy-resolved neutron imaging for reconstruction of strain introduced by cold working

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    Energy-resolved neutron transmission imaging is used to reconstruct maps of residual strains in drilled and cold-expanded holes in 5-mm and 6.4-mm-thick aluminum plates. The possibility of measuring the positions of Bragg edges in the transmission spectrum in each 55 × 55 µm2 pixel is utilized in the reconstruction of the strain distribution within the entire imaged area of the sample, all from a single measurement. Although the reconstructed strain is averaged through the sample thickness, this technique reveals strain asymmetries within the sample and thus provides information complementary to other well-established non-destructive testing methods

    Stratospheric Influence On The Breakdown Of A January 2009 Blocking Episode

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    In previous research on atmospheric blocking the interest has primarily been on the onset of blocking. To fully understand a blocking episode, the end, or breakdown, must also be investigated. The focus of this research was to examine the dynamics of block breakdown, with special notice to the stratospheric influence. Several factors that have been previously discussed in block onset, including advection of quasi-geostrophic potential vorticity, temperature advection, and adiabatic temperature changes, were examined both at block breakdown and block onset for comparison. The calculations were done on Weather Research and Forecasting (WRF) model runs. The WRF was initialized with three different types of initial and boundary conditions from the blocking episode on 10-20 January 2009: a Global Forecast System (GFS) Final Analysis, GFS real-time 180 hour forecast, and modified GFS real-time 180 hour forecast. To perform the runs based on modified GFS forecasts, several temperature modifications were made in both the stratosphere and lower troposphere on both onset and breakdown runs of the WRF. The impact of the modifications were observed to be the greatest magnitude at block breakdown. Cooling the stratosphere had the effect of sustaining the block for up to 12 hours, and up to 24 hours longer when the troposphere was warmed. The modification at block onset did not change the timing significantly but did impact the strength. In the future, this technique will be applied to other case studies so that the results may be corroborated, as one case study does not indicate a more general pattern
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