1,613 research outputs found
History, Sociology, Modernity : How Connect?
Special Issue on 'The State of Scottish History: Past, Present and Future'Peer reviewedPublisher PD
Thermoelectric performance of multiphase XNiSn (X = Ti, Zr, Hf) half-Heusler alloys
Quantitative X-ray powder diffraction analysis demonstrates that mixing Ti, Zr and Hf on the ionic site in the half-Heusler structure, which is a common strategy to lower the lattice thermal conductivity in this important class of thermoelectric materials, leads to multiphase behaviour. For example, nominal Ti0.5Zr0.5NiSn has a distribution of Ti1−xZrxNiSn compositions between 0.24 ≤ x ≤ 0.70. Similar variations are observed for Zr0.50Hf0.5NiSn and Ti0.5Hf0.5NiSn. Electron microscopy and elemental mapping demonstrate that the main compositional variations occur over micrometre length scales. The thermoelectric power factors of the mixed phase samples are improved compared to the single phase end-members (e.g. S2/ρ = 1.8 mW m−1 K−2 for Ti0.5Zr0.5NiSn, compared to S2/ρ = 1.5 mW m−1 K−2 for TiNiSn), demonstrating that the multiphase behaviour is not detrimental to electronic transport. Thermal conductivity measurements for Ti0.5Zr0.5NiSn0.95 suggest that the dominant reduction comes from Ti/Zr mass and size difference phonon scattering with the multiphase behaviour a secondary effect
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Characteristics of successful interventions to reduce turnover and increase retention of early career nurses: a systematic review
Background
nurse shortages have been identified as central to workforce issues in healthcare systems globally and although interventions to increase the nursing workforce have been implemented, nurses leaving their roles, particularly in the first year after qualification, present a significant barrier to building the nurse workforce.
Objective
to evaluate the characteristics of successful interventions to promote retention and reduce turnover of early career nurses.
Design
this is a systematic review
Data sources
Online databases including Academic Search Complete, Medline, Health Policy reference Centre, EMBASE, Psychinfo, CINAHL and the Cochran Library were searched to identify relevant publications in English published between 2001 and April 2018. Studies included evaluated an intervention to increase retention or reduce turnover and used turnover or retention figures as a measure.
Review methods
The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were quality-assessed using the Joanna Briggs Institute Critical Appraisal tools for Quasi Experimental and Randomised Controlled Trials. Retention/turnover data were used to guide the comparison between studies and appropriate measures of central tendency and dispersion were calculated and presented, based on the normality of the data.
Results
A total of 11, 656 papers were identified, of which 53 were eligible studies. A wide variety of interventions and components within those interventions were identified to improve nurse retention. Promising interventions appear to be either internship/residency programmes or orientation/transition to practice programmes, lasting between 27-52 weeks, with a teaching and preceptor and mentor component.
Conclusions
Methodological issues impacted on the extent to which conclusions could be drawn, even though a large number of studies were identified. Future research should focus on standardising the reporting of interventions and outcome measures used to evaluate these interventions and carrying out further research with rigorous methodology. Clinical practice areas are recommended to assess their current interventions against the identified criteria to guide development of their effectiveness. Evaluations of cost-effectiveness are considered an important next step to maximise return on investment
Developing a model to motivate and teach new members to do relational evangelism
https://place.asburyseminary.edu/ecommonsatsdissertations/1518/thumbnail.jp
International Trade In Dairy Products: Processors Market Power
In the past two decades there has been a considerable amount of research conducted into the international price and trade effects of government intervention in the dairy industries of several countries. Recently, the conclusions of those studies have been questioned owing to the rising concentration in the processor sector. Since processors are increasingly multinational in nature and a few of them are operating around the globe, there is a possibility that the processors will influence both the farm and retail prices through their having market power.Multinational, Processor market power, Dairy products, International Relations/Trade,
Women's experience of male circumcision in Papua New Guinea: a grounded theory study
Background: Understanding how women experience and manage the myriad issues of male circumcision (MC) for themselves, their sexual partners and their sons is essential to understanding broader HIV and sexual health issues in Papua New Guinea (PNG). A great diversity of traditional and contemporary circumcision and foreskin cutting practices exist across the country. Medical MC is currently being investigated as a HIV prevention strategy. Studies have documented mixed responses by women to MC as a HIV prevention method in PNG.
Methods: Between 2012 and 2014, a grounded theory study was conducted using a two-phase approach. Data from a large mixed methods multi-site MC study in 2010/2011 was analysed for themes to inform specific questions for women. Semi-structured interviews and focus group discussions, that incorporated visual methods such as storyboarding, were then conducted with 67 women at two of the initial study sites - a rural oil palm plantation and an urban university site. Data were inductively analysed to identify codes, categories and a grounded theory.
Results: Women have extensive knowledge about MC and foreskin cutting practices, despite cultural norms that mean most women do not participate in decision-making about MC or other penile modifications. Women gain knowledge through personal (sometimes negative) experiences of their partners or children, through cultural traditions and/or through formal training or education. Women who have formal education or training, or who hold formal roles in their communities reported a greater power of choice about their own decision-making, including how MC affects them. Educated women reported more opportunities to influence their partner's decision about MC or other penile modifications, to choose a new partner or arrange MC for their male child/ren.
Conclusions: Increased formal and informal education (such as HIV and sexual health training) results in increased status for women and access to a greater range of choices. The often culturally sanctioned low-status roles for women in PNG can be changed with training and/or formal education, which gives more power and thus more choices. If women have greater power of choice, they are less vulnerable to harmful, unintended consequences that may result from a policy of medical MC
Simulation and analysis of solenoidal ion sources
We present a detailed analysis and simulation of solenoidal, magnetically confined electron bombardment ion sources, aimed at molecular beam detection. The aim is to achieve high efficiency for singly ionized species while minimizing multiple ionization. Electron space charge plays a major role and we apply combined ray tracing and finite element simulations to determine the properties of a realistic geometry. The factors controlling electron injection and ion extraction are discussed. The results from simulations are benchmarked against experimental measurements on a prototype source
Using EBSD and TEM-Kikuchi patterns to study local crystallography at the domain boundaries of lead zirconate titanate
Reliable EBSD mapping of 90° domains in a tetragonal ferroelectric perovskite has been achieved for the first time, together with reliable automated orientation determination from TEM-Kikuchi patterns. This has been used to determine misorientation angles at 90° domain boundaries and thus local <i>c</i>/<i>a</i> ratios. The sources of orientation noise/error and their effects on the misorientation angle data have been thoroughly analyzed and it is found that this gives a cosine distribution of misorientation angles about the mean with a characteristic width related to the width of the orientation noise distribution. In most cases, a good agreement is found between local <i>c</i>/<i>a</i> ratios and global measurements by X-ray diffraction, but some clear discrepancies have also been found suggesting that real local variations are present, perhaps as a consequence of compositional inhomogeneities
‘Fair trade’ coffee and the mitigation of local oligopsony power
In recent years, there has been considerable growth in ‘fair trade’ markets for several commodities, most notably coffee. We argue that coffee is grown under conditions that might well subject growers to the market power of downstream intermediaries (processors). Using an approach designed to evaluate the effects of state trading enterprises on trade and welfare, we develop an oligopsony model of intermediaries. In this model, fair-trade processors optimise a welfare function that includes the producer surplus of coffee growers. This concern for growers' welfare among some processing firms helps to alleviate the market power distortion. We calibrate the model to price data reported by a fair-trade organisation and consider the counterfactual removal of fair-trade behaviour by processors. As expected, the income of coffee growers (in aggregate) is reduced, though the effects are quite small
Characterisation of the Medipix3 detector for 60 and 80 keV electrons
In this paper we report quantitative measurements of the imaging performance for the current generation of hybrid pixel detector, Medipix3, used as a direct electron detector. We have measured the modulation transfer function and detective quantum efficiency at beam energies of 60 and 80 keV. In single pixel mode, energy threshold values can be chosen to maximize either the modulation transfer function or the detective quantum efficiency, obtaining values near to, or exceeding those for a theoretical detector with square pixels. The Medipix3 charge summing mode delivers simultaneous, high values of both modulation transfer function and detective quantum efficiency. We have also characterized the detector response to single electron events and describe an empirical model that predicts the detector modulation transfer function and detective quantum efficiency based on energy threshold. Exemplifying our findings we demonstrate the Medipix3 imaging performance recording a fully exposed electron diffraction pattern at 24-bit depth together with images in single pixel and charge summing modes. Our findings highlight that for transmission electron microscopy performed at low energies (energies <100 keV) thick hybrid pixel detectors provide an advantageous architecture for direct electron imaging
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