105 research outputs found
NON-FREE VORTEX FLOW EFFECTS IN AN AXIAL FLOW ROTOR
This paper presents the analysis of three-dimensional flow field developing through an industrial
axial flow fan rotor of non-free vortex design carried out on the basis of concerted experimental and
numerical investigations. The paper focuses on non-free vortex flow effects requiring
consideration in rotor blade design theories. The distortion of stream surfaces through the blading
has been observed and a quantitative analysis of its effects on the blade loading condition has been
carried out in the through-flow core region. The streamlines close to the blades have been modelled
fitting to outward and inward conical stream tubes on the blade suction and pressure sides,
respectively - termed `cone couple model´. It has been pointed out that the
blade lift can be
satisfactorily described at midspan on the basis of the cone couple model, with
use of pitch-averaged flow data. The loading aspects of the tested axial rotor have been discussed on the basis of
both the pressure distribution in the vicinity of the blades and pitch-averaged flow data obtained
upstream and downstream of the rotor. Sample calculations suggested that separate optimisation of
the blade suction and pressure sides is essential if the three-dimensional blade-to-blade flow is
intended to be considered in NFV fan design with use of two-dimensional cascade data
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Operationalizing Co-Production in Public Services Delivery: The contribution of service blueprinting
We have argued for public services to move away from product-dominant logic towards a service approach. By taking a services orientation, the experience, inter-organizational, and systemic nature of public services delivery can be considered along with the role of the service user as a co-producer. In this article, we unpack how co-production can be operationalized through the application of service blueprinting. This article presents an example within higher education where the creation of a blueprint brought together staff and students to focus on the design of student enrolment, resulting in improved student experience and supporting co-production
Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial
Background
Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects.
Methods
FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762.
Findings
Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months.
Interpretation
Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function.
Funding
UK Stroke Association and NIHR Health Technology Assessment Programme
The impact of adopting a research orientation towards use of the Pupil Premium Grant in preparing beginning teachers in England to understand and work effectively with young people living in poverty
The introduction in England of the Pupil Premium Grant (PPG) provided a stimulus to ensure that beginning teachers understand the nature of poverty and critically examine strategies used by schools seeking to overcome the barriers to academic achievement that it presents. This article explores the effects of asking student-teachers within a well-established initial teacher education partnership to adopt a research orientation towards the use of PPG funding. It focuses on the student-teachers’ experiences and developing thinking as they engaged in small-scale investigative projects and on the perspectives of their school-based teacher educators (professional tutors). Whole-course evaluation data suggest that most projects operated successfully, with the student-teachers encouraged to ask critical questions about current practices, drawing on different kinds of evidence. Three case studies illustrate the diversity of approaches adopted towards the project, reflecting the views of individual professional tutors and the complex interplay between the competing object motives of different participants
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