3,088 research outputs found
Weathering and brittleness in shale fill dams and embankments
Research and industrial concern has been expressed about the behaviour of mudrocks when used in engineering structures. In particular the loss of strength in shale fills caused by chemical weathering processes and by progressive failure arising from overstressing and brittleness is an important consideration in design. A literature review into use of the term 'brittleness' to describe this loss of shear strength has revealed infrequent references, but those that were found refer to a wide scope of failures including liqufaction events and long term slope stability problems. The use of large size shear box equipment has been reviewed as an appropriate method of testing the brittleness of shale fills in the laboratory. A range of materials, from fresh shale to shales retrieved from dams of different ages in the north east of England, has been collected for shear strength testing and for chemical and mineralogical examination to determine the condition of the fill. Research has concentrated on such rocks as it was possible to obtain. Although the samples have not exhibited wide lithological and geotechnical variations the work has highlighted several significant features including the need for resolving appropriate methods of testing. The results of the work were generally in accordance with earlier research on Carboniferous rocks by suggesting similar material trends in, on the one hand, Namurian shale dams and associated spoil heaps and, on the other hand, colliery spoil heaps of Westphalian shale as had been previously observed
Passing the Baton: An Integrated Approach to Succession Planning for Local Health Departments
Succession planning is a process that requires more than just an organizational chart illustration of who holds what position within the organization. The process also requires developing and implementing guidelines and best practices to identify and address current and future workforce development needs. Succession planning contributes to an organization’s success by providing a mechanism that ensures a talent pool of replacements has been suitably groomed and equipped to fill critical vacancies when retirements occur or on short notice. It can generate operational efficiencies for the field of public health that is faced with chronic budgetary pressure and an impending mass exodus of a workforce generation that inhabits a wealth of knowledge.
Public health in the United States is experiencing a dynamic shift as the baby boomers, those 65 million persons born between 1964 to 1955, are eligible for retirement and are actively leaving the workforce in droves even amid the COVID-19 pandemic. The baby boomers’ mass exit leaves a vast void and creates vacancies that will need to be filled quickly.
This scoping study identified and summarized succession planning guidelines and best practices in published reports and gray literature and consolidated critical domains and processes into a sustainable framework for adaptation in LHDs. Best practices and guidelines were identified and integrated into a six-step cross-cutting framework that encompasses overarching domains necessary for applicability and sustainability. The integrated framework for succession planning includes the following steps: (1) strategic planning, (2) workforce analysis, (3) selection and identification, and (4) preparation for promotion, and all-encompassing processes that ensure fidelity of the integrated framework include implementation and evaluation at each domain point. Cross-cutting elements critical for developing and implementing robust succession planning processes include leadership buy-in, stakeholder engagement, transparency, fairness and equity, and a systematic approach to knowledge transfer.
The study developed a toolkit for succession planning implementation in LHDs, which consists of a description of the integrated framework, its six domains and associated processes, and a checklist to jumpstart succession planning in LHDs. The toolkit can help LHDs successfully implement sustainable succession planning that preserves intellectual knowledge and ensures that it is transferred from one workforce generation to the next
New laboratory methodologies to analyse the top of rail friction modifier performance across different test scales
Test methodologies originally developed for greases have been adapted to be used for top of rail friction modifiers (TORFMs). This has included: a small-scale benchtop tribometer to measure the tackiness of different TORFMs, attaching an applicator bar to a section of rail and rolling a scaled-wheel through the TORFM applied to the rail head to analyse the effect of different variables on pick-up, and applying TORFM to a full-scale test facility to analyse the scaling effects and the effect of slip, load and speed on pick-up. These methods can be used to measure the relative performance of different TORFMs with respect to how much product is picked up by the wheel. The results have shown that the relative ranking of different TORFMs is the same across the three test scales. This shows that these small-scale test methods that are more suitable for inclusion in test standards could be used to reduce the need for the more time-consuming and expensive larger scale tests, as the relative performance is the same
Review of top of rail friction modifier tribology
© 2016 Informa UK Limited, trading as Taylor & Francis Group.The aim of this paper was to review the current state of research for top of rail friction modifiers (TORFM). In the railway industry, friction modifiers is a catch all term for a wide range of products applied for different purposes which has led to confusion. It is hoped that recently published definitions will aid industry to a better understanding of the different products and how they function. The benefits of friction modifiers are well understood with a large body of research supporting the benefits. Comparatively, there is a lot less knowledge of the optimum amount of product to achieve the benefits or how far down the track from an application site the benefit will be seen. Modelling of the products is another area where there is little research, with most of the modelling papers found focussing on dry wheel–rail contact due to the complexity of introducing a third-body layer to a friction force model. Furthermore, only one paper was found which relates how friction modifiers are affected by contaminants or other applied products such as lubricants. With many different products applied to wheels and rail for different purposes, understanding their interaction is key. At the time of this review, there are currently no standards that prescribe how TORFM should behave although the European Committee for Standardisation is currently developing them at the moment. This review has also attempted to appraise the research against a set of criteria. Depending on how many of the criteria the piece of research filled, it was categorised as A, B or C. It was found that most of the research was of category, this was mainly due to only one test method being used or the scale presented. Category A research incorporated modelling or multiple test-scales to support the results presented
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Therapy for naming difficulties in bilingual aphasia: which language benefits?
Background: The majority of the world's population is bilingual. Yet, therapy studies involving bilingual people with aphasia are rare and have produced conflicting results. One recent study suggested that therapy can assist word retrieval in bilingual aphasia, with effects generalising to related words in the untreated language. However, this cross-linguistic generalisation only occurred into the person's stronger language (L1). While indicative, these findings were derived from just three participants, and only one received therapy in both languages.
Aims: This study addressed the following questions. Do bilingual people with aphasia respond to naming therapy techniques developed for the monolingual population? Do languages respond differently to therapy and, if so, are gains influenced by language dominance? Does cross-linguistic generalisation occur and does this depend on the therapy approach? Is cross-linguistic generalisation more likely following treatment in L2 or L1?
Methods & Procedures: The study involved five aphasic participants who were bilingual in English and Bengali. Testing showed that their severity and dominance patterns varied, so the study adopted a case series rather than a group design. Each person received two phases of naming therapy, one in Bengali and one in English. Each phase treated two groups of words with semantic and phonological tasks, respectively. The effects of therapy were measured with a picture-naming task involving both treated and untreated (control) items. This was administered in both languages on four occasions: two pre-therapy, one immediately post-therapy and one 4 weeks after therapy had ceased. Testing and therapy in Bengali was administered by bilingual co-workers.
Outcomes & Results: Four of the five participants made significant gains from at least one episode of therapy. Benefits arose in both languages and from both semantic and phonological tasks. There were three instances of cross-linguistic generalisation, which occurred when items had been treated in the person's dominant language using semantic tasks.
Conclusions & Implications: This study suggests that ‘typical’ naming treatments can be effective for some bilingual people with aphasia, with both L1 and L2 benefiting. It offers evidence of cross-linguistic generalisation, and suggests that this is most likely to arise from semantic therapy approaches. In contrast to some results in the academic literature, the direction of generalisation was from LI to L2. The theoretical implications of these findings are considered. Finally, the results support the use of bilingual co-workers in therapy delivery
The effectiveness and cost-effectiveness of shared care: protocol for realist review
BACKGROUND: Shared care (an enhanced information exchange over and above routine outpatient letters) is commonly used to improve care coordination and communication between a specialist and primary care services for people with long-term conditions. Evidence of the effectiveness and cost-effectiveness of shared care is mixed. Informed decision-making for targeting shared care requires a greater understanding of how it works, for whom it works, in what contexts and why. This protocol outlines how realist review methods can be used to synthesise evidence on shared care for long-term conditions. A further aim of the review is to explore economic evaluations of shared care. Economic evaluations are difficult to synthesise due to problems in accounting for contextual differences that impact on resource use and opportunity costs. Realist review methods have been suggested as a way to overcome some of these issues, so this review will also assess whether realist review methods are amenable to synthesising economic evidence. METHODS/DESIGN: Database and web searching will be carried out in order to find relevant evidence to develop and test programme theories about how shared care works. The review will have two phases. Phase 1 will concentrate on the contextual conditions and mechanisms that influence how shared care works, in order to develop programme theories, which partially explain how it works. Phase 2 will focus on testing these programme theories. A Project Reference Group made up of health service professionals and people with actual experience of long-term conditions will be used to ground the study in real-life experience. Review findings will be disseminated through local and sub-national networks for integrated care and long-term conditions. DISCUSSION: This realist review will explore why and for whom shared care works, in order to support decision-makers working to improve the effectiveness of care for people outside hospital. The development of realist review methods to take into account cost and cost-effectiveness evidence is particularly innovative and challenging, and if successful will offer a new approach to synthesising economic evidence. This systematic review protocol is registered on the PROSPERO database (registration number: CRD42012002842)
IMAGE: a multivariate multi-site stochastic weather generator for European weather and climate
Capturing the spatial and temporal correlation of multiple variables in a weather generator is challenging. A new massively multi-site, multivariate daily stochastic weather generator called IMAGE is presented here. It models temperature and precipitation variables as latent Gaussian variables with temporal behaviour governed by an auto-regressive model whose residuals and parameters are correlated through resampling of principle component time series of empirical orthogonal function modes. A case study using European climate data demonstrates the model’s ability to reproduce extreme events of temperature and precipitation. The ability to capture the spatial and temporal extent of extremes using a modified Climate Extremes Index is demonstrated. Importantly, the model generates events covering not observed temporal and spatial scales giving new insights for risk management purposes
Smart-traps combined with molecular on-site detection to monitor Monochamus spp. and associated pine wood nematode
A comparison of friction modifier performance using two laboratory test scales
This paper describes two methods, carried out at two different test scales, for assessing the friction modifier performance. Study A used the wear data from a full-scale rig test at the voestalpine Schienen GmbH and compared it with the wear data from twin disc tests using the SUROS test machine at the University of Sheffield. Study B compared the ‘retentivity’ data, from a full-scale rig at the University of Sheffield, with the data from the SUROS tests. Study A concluded that a good correlation existed between the two scales although assumptions made in the full-scale contact calculation introduce a large spread into the results. There was a greater correlation between the two data sets at more severe contact conditions. Study B showed a different baseline coefficient of traction between the two scales and that a longer test length is required to fully evaluate the ‘retention’ of the friction modifier on the full-scale rig. The paper expands on a previous conference presentation on the same subject. Additional information on the test procedure and test rigs is included here. Surface and subsurface analyses of the SUROS test samples have also been added. The analyses have shown that applying the friction modifier leads to a similar wear mechanism as for the dry contact, but the wear is less severe and there is less subsurface deformation. A discussion describing the differences in test scales and comparing lab tests to field operation is also included
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