73 resultados para Scale of evaluation


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The spontaneous oxidation of CO adsorbates on a Pt electrode modified by Ru under open circuit (OC) conditions in perchloric acid solution has been followed, for the first time, using in situ FTIR spectroscopy, and the dynamics of the surface processes taking place have been elucidated. The IR data show that adsorbed CO present on both the Ru and Pt domains and can be oxidized by the oxygen-containing adlayer on the Ru in a chemical process to produce CO under OC conditions. There is a free exchange of CO is between the Ru and Pt sites. Oxidation of CO may take place at the edges of the Ru islands, but CO is transfer, at least on the time scale of these experiments, allows the two different populations to maintain equilibrium. Oxidation is limited in this region by the rate of supply of oxygen to die surface of the catalyst. A mechanism is postulated to explain the observed behavior.

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Background: Large-scale randomised controlled trials are relatively rare in education. The present study approximates to, but is not exactly, a randomised controlled trial. It was an attempt to scale up previous small peer tutoring projects, while investing only modestly in continuing professional development for teachers.Purpose: A two-year study of peer tutoring in reading was undertaken in one local education authority in Scotland. The relative effectiveness of cross-age versus same-age tutoring, light versus intensive intervention, and reading versus reading and mathematics tutoring were investigated.Programme description (if relevant): The intervention was Paired Reading, a freely available cross-ability tutoring method applied to books of the pupils' choice but above the tutee's independent readability level. It involves Reading Together and Reading Alone, and switching from one to the other according to need.Sample: Eighty-seven primary schools of overall average socio-economic status, ability and gender in one council in Scotland. There were few ethnic minority students. Proportions of students with special needs were low. Children were eight and 10 years old as the intervention started. Macro-evaluation n = 3520. Micro-evaluation Year 1 15 schools n = 592, Year 2 a different 15 schools n = 591, compared with a comparison group of five schools n = 240.Design and methods: Almost all the primary schools in the local authority participated and were randomly allocated to condition. A macro-evaluation tested and retested over a two-year period using Performance Indicators in Primary Schools. A micro-evaluation tested and retested within each year using norm-referenced tests of reading comprehension. Macro-evaluation was with multi-level modelling, micro-evaluation with descriptive statistics and effect sizes, analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA).Results: Macro-evaluation yielded significant pre-post gains in reading attainment for cross-age tutoring over both years. No other differences were significant. Micro-evaluation yielded pre-post changes in Year 1 (selected) and Year 2 (random) greater than controls, with no difference between same-age and cross-age tutoring. Light and intensive tutoring were equally effective. Tutoring reading and mathematics together was more effective than only tutoring reading. Lower socio-economic and lower reading ability students did better. Girls did better than boys. Regarding observed implementation quality, some factors were high and others low. Few implementation variables correlated with attainment gain.Conclusions: Paired Reading tutoring does lead to better reading attainment compared with students not participating. This is true in the long term (macro-evaluation) for cross-age tutoring, and in the short term (micro-evaluation) for both cross-age and same-age tutoring. Tutors and tutees benefited. Intensity had no effect but dual tutoring did have an effect. Low-socio-economic status, low-ability and female students did better. The results of the different forms of evaluation were indeed different. There are implications for practice and for future research. © 2012 Copyright Taylor and Francis Group, LLC.

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Rationale, aims and objectives: This study aims to examine the public's knowledge and perceptions of connected health (CH).

Methods: A structured questionnaire was administered by face-to-face interview to an opportunistic sample of 1003 members of the public in 11 shopping centres across Northern Ireland (NI). Topics included public knowledge of CH, opinions about who should provide CH and views about the use of computers in health care. Multivariable analyses were conducted to assess respondents' willingness to use CH in the future.

Results: Sixty-seven per cent of respondents were female, 31% were less than 30 years old and 22% were over 60 years. Most respondents had never heard of CH (92%). Following a standard definition, the majority felt CH was a good idea (≈90%) and that general practitioners were in the best position to provide CH; however, respondents were equivocal about reductions in health care professionals' workload and had some concerns about the ease of device use. Factors positively influencing willingness to use CH in the future included knowledge of someone who has a chronic disease, residence in NI since birth and less concern about the use of information technology (IT) in health care. Those over 60 years old or who felt threatened by the use of IT to store personal health information were less willing to use CH in the future.

Conclusion: Increased public awareness and education about CH is required to alleviate concerns and increase the acceptability of this type of care.

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The consequences of biodiversity loss in the face of environmental change remain difficult to predict, given the complexity of interactions among species and the context-dependency of their functional roles within ecosystems. Predictions may be enhanced by studies testing how the interactive effects of species loss from different functional groups vary with important environmental drivers. On rocky shores, limpets and barnacles are recognised as key grazers and ecosystem engineers, respectively. Despite the large body of research examining the combined effects of limpet and barnacle removal, it is unclear how their relative importance varies according to wave exposure, which is a dominant force structuring intertidal communities. We tested the responses of algal communities to the removal of limpets and barnacles on three sheltered and three wave-exposed rocky shores on the north coast of Ireland. Limpet removal resulted in a relative increase in microalgal biomass on a single sheltered shore only, but led to the enhanced accumulation of ephemeral macroalgae on two sheltered shores and one exposed shore. On average, independently of wave exposure or shore, ephemeral macroalgae increased in response to limpet removal, but only when barnacles were removed. On two sheltered shores and one exposed shore, however, barnacles facilitated the establishment of fucoid macroalgae following limpet removal. Therefore, at the scale of this study, variability among individual shores was more important than wave exposure per se in determining the effect of limpet removal and its interaction with that of barnacles. Overall, these findings demonstrate that the interactive effects of losing key species from different functional groups may not vary predictably according to dominant environmental factors.

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Introduction: There are many challenges in delivering rural health services; this is particularly true for the delivery of palliative care. Previous work has identified consistent themes around end-of-life care, including caregiver burden in providing care, the importance of informal care networks and barriers imposed by geography. Despite these well-known barriers, few studies have explored the experience of palliative care in rural settings. The purpose of the present study was to compare the experiences of rural family caregivers actively providing end-of-life care to the experiences of their urban counterparts. Methods: Caregivers' perceived health status, the experience of burden in caregiving, assessment of social supports and the pattern of formal care used by the terminally ill were explored using a consistent and standardized measurement approach. A cross-sectional survey study was conducted with 100 informal caregivers (44 rural, 56 urban) actively providing care to a terminally ill patient recruited from a publicly funded community agency located in northeastern Ontario, Canada. The telephone-based survey included questions assessing: (i) caregiver perceived burden (14-item instrument based on the Caregiver's Burden Scale in End-of-Life Care [CBS-EOLC]); (ii) perceived social support (modified version of the Multidimensional Scale of Perceived Social Support [MSPSS] consisting of 12 items); and (iii) functional status of the care recipient (assessed using the Eastern Collaborative Oncology Group performance scale). Results: Rural and urban caregivers were providing care to recipients with similar functional status; the majority of care recipients were either capable of all self-care or experiencing some limitation in self-care. No group differences were observed for caregiver perceived burden: both rural and urban caregivers reported low levels of burden (CBS-EOLC score of 26.5 [SD=8.1] and 25.0 [SD=9.2], respectively; p=0.41). Urban and rural caregivers also reported similarly high levels of social support (mean MSPSS total score of 4.3 [SD=0.7] and 4.1 [SD=0.8], respectively; p=0.40). Although caregivers across both settings reported using a comparable number of services (rural 4.8 [SD=1.9] vs urban 4.5 [SD=1.8]; p=0.39), the types of services used differed. Rural caregivers reported greater use of family physicians (65.1% vs 40.7%; p=0.02), emergency room visits (31.8% vs 13.0%; p=0.02) and pharmacy services (95.3% vs 70.4%; p=0.002), while urban caregivers reported greater use of caregiver respite services (29.6% vs 11.6%; p=0.03). Conclusion: Through the use of standardized tools, this study explored the experiences of rural informal family caregivers providing palliative care in contrast to the experiences of their urban counterparts. The results of the present study suggest that while there are commonalities to the caregiving experience regardless of setting, key differences also exist. Thus, location is a factor to be considered when implementing palliative care programs and services. © K Brazil, S Kaasalainen, A Williams, C Rodriguez, 2013.

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A novel numerical technique is proposed to model thermal plasma of microseconds/milliseconds time-scale effect. Modelling thermal plasma due to lightning strike will allow the estimation of electric current density, plasma pressure, and heat flux at the surface of the aircraft structure. These input data can then be used for better estimation of the mechanical/thermal induced damage on the aircraft structures for better protection systems design. Thermal plasma generated during laser cutting, electric (laser) welding and other plasma processing techniques have been the focus of many researchers. Thermal plasma is a gaseous state that consists from a mixture of electrons, ions, and natural particles. Thermal plasma can be assumed to be in local thermodynamic equilibrium, which means the electrons and the heavy species have equal temperature. Different numerical techniques have been developed using a coupled Navier Stokes – Heat transfer – Electromagnetic equations based on the assumption that the thermal plasma is a single laminar gas flow. These previous efforts focused on generating thermal plasma of time-scale in the range of seconds. Lighting strike on aircraft structures generates thermal plasma of time-scale of milliseconds/microseconds, which makes the previous physics used not applicable. The difficulty comes from the Navier-Stokes equations as the fluid is simulated under shock load, this introducing significant changes in the density and temperature of the fluid.

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The radiative decay of surface plasmon polaritons has been investigated in an attempt to characterize the surface roughness of Ag films prepared under different conditions. The polaritons were excited by the method of attenuated total reflection of light. The films were deposited on the face of a 60-degrees BK-7 glass prism at a rate that was deliberately fixed in two different ranges (centred on 0.1 and 10 nm s-1) and in some cases a CaF2 underlayer was used to roughen the film surfaces. The intensity of the scattered light emitted from the opposite face of the films was measured as a function of direction for each using the same sensitivity scale and was correlated with the preparation of the film. It was found that on nominally smooth substrates fast-deposited thinner films give out more light and are deduced to have greater short wavelength (300-600 nm) roughness amplitude. There is also evidence for long wavelenth (7 mum) periodic roughness due to the prism substrate itself. On CaF2 roughened surfaces the light output from the films is further increased and the peak intensity is backward directed with respect to the exciting laser beam direction. Here roughness on a lateral scale of 350 nm is responsible. Also, elastic scattering of surface plasmon polaritons at grain boundaries reduces the light output from fast deposited, small grain, films on CaF2 roughened surfaces. Overall, a consistent picture of roughness induced radiative polariton decay emerges for all cases studied.

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RATIONALE, AIMS AND OBJECTIVES: Health care services offered to the public should be based on the best available evidence. We aimed to explore pharmacy tutors' and trainees' views on the importance of evidence when making decisions about over-the-counter (OTC) medicines and also to investigate whether the tutor influenced the trainee in practice.

METHODS: Following ethical approval and piloting, semi-structured interviews were conducted with pharmacy graduates (trainees) and pharmacist tutors. Transcribed interview data were entered into the NVivo software package (version 10), coded and analysed via thematic analysis.

RESULTS: Twelve trainees (five males, seven females) and 11 tutors (five males, six females) participated. Main themes that emerged were (in)consistency and contradiction, confidence, acculturation, and continuation and perpetuation. Despite having an awareness of the importance and potential benefits, an evidence-based approach did not seem to be routinely or consistently implemented in practice. Confidence in products was largely derived from personal use and patient feedback. A lack of discussion about evidence was justified on the basis of not wanting to lessen patient confidence in requested product(s) or possibly negating the placebo effect. Trainees became acculturated to 'real-life' practice; university teaching and evidence was deemed less relevant than meeting customer expectations. The tutor's actions were mirrored by their trainee resulting in continuation and perpetuation of the same professional attitudes and behaviours.

CONCLUSIONS: Evidence appeared to have limited influence on OTC decision making. The tutor played a key role in the trainee's professional development. More work could be performed to investigate how evidence can be regarded as relevant and something that is consistently implemented in practice.

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Leptospirosis is a globally important zoonotic infection caused by spirochaetes of the genus Leptospira. It is transmitted to humans by direct contact with infected animals or indirectly via contaminated water. It is mainly a problem of the resource-poor developing countries of the tropical and sub-tropical regions of the world but outbreaks due to an increase in travel and recreational activities have been reported in developed and more industrialized areas of the world. Current methods of diagnosis are costly, time-consuming and require the use of specialized laboratory equipment and personnel. The purpose of this paper is to report the validation of the 'Leptorapide®' test (Linnodee Ltd, Northern Ireland) for the diagnosis of human leptospirosis. It is a simple one-step latex agglutination assay performed using equal volumes of serum sample and antigen-bound latex beads. Evidence of leptospiral antibodies is determined within minutes. Agglutination is scored on a scale of 1-5 and the results interpreted using a score card provided with the kit. Validation has been performed with a large sample size obtained from individuals originating from various parts of the world including Brazil and India. The test has shown sensitivity and specificity values of 97·1% and 94·0%, respectively, relative to the microscopic agglutination test. The results demonstrate that Leptorapide offers a cost-effective and accurate alternative to the more historical methods of antibody detection.

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During the 1950s and 1960s, excavations by the Sarawak Museum at Niah Cave in northwest Borneo produced an enormous archive of records and artefacts, including in excess of 750,000 macro- and micro-vertebrate remains. The excellent state of preservation of the animal bone, dating from the Late Pleistocene (c. 40 kya) to as recently as c. 500 years ago had the potential to provide unparalleled zooarchaeological information about early hunter-gatherer resource procurement, temporal changes in subsistence patterning, and the impact of peoples on the local and regional environment in Island Southeast Asia. However, the coarse-grained methods of excavation employed during the original investigations and the sheer scale of the archaeological record and bone assemblages dissuaded many researchers from attempting to tackle the Niah archives. This paper outlines how important information on the nature of the archaeological record at Niah has now finally been extracted from the archive using a combination of zooarchaeological analysis and reference to the extensive archaeological records from the site. Copyright (C) 2009 John Wiley & Sons, Ltd.

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Lap joints are widely used in the manufacture of stiffened panels and influence local panel sub-component stability, defining buckling unit dimensions and boundary conditions. Using the Finite Element method it is possible to model joints in great detail and predict panel buckling behaviour with accuracy. However, when modelling large panel structures such detailed analysis becomes computationally expensive. Moreover, the impact of local behaviour on global panel performance may reduce as the scale of the modelled structure increases. Thus this study presents coupled computational and experimental analysis, aimed at developing relationships between modelling fidelity and the size of the modelled structure, when the global static load to cause initial buckling is the required analysis output. Small, medium and large specimens representing welded lap-joined fuselage panel structure are examined. Two element types, shell and solid-shell, are employed to model each specimen, highlighting the impact of idealisation on the prediction of welded stiffened panel initial skin buckling.

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This paper describes how urban agriculture differs from conventional agriculture not only in the way it engages with the technologies of growing, but also in the choice of crop and the way these are brought to market. The authors propose a new model for understanding these new relationships, which is analogous to a systems view of information technology, namely Hardware-Software- Interface.
The first component of the system is hardware. This is the technological component of the agricultural system. Technology is often thought of as equipment, but its linguistic roots are in ‘technis’ which means ‘know how’. Urban agriculture has to engage new technologies, ones that deal with the scale of operation and its context which is different than rural agriculture. Often the scale is very small, and soils are polluted. There this technology in agriculture could be technical such as aquaponic systems, or could be soil-based agriculture such as allotments, window-boxes, or permaculture. The choice of method does not necessarily determine the crop produced or its efficiency. This is linked to the biotic that is added to the hardware, which is seen as the ‘software’.
The software of the system are the ecological parts of the system. These produce the crop which may or may not be determined by the technology used. For example, a hydroponic system could produce a range of crops, or even fish or edible flowers. Software choice can be driven by ideological preferences such as permaculture, where companion planting is used to reduce disease and pests, or by economic factors such as the local market at a particular time of the year. The monetary value of the ‘software’ is determined by the market. Obviously small, locally produced crops are unlikely to compete against intensive products produced globally, however the value locally might be measured in different ways, and might be sold on a different market. This leads to the final part of the analogy - interface.
The interface is the link between the system and the consumer. In traditional agriculture, there is a tenuous link between the producer of asparagus in Peru and the consumer in Europe. In fact very little of the money spent by the consumer ever reaches the grower. Most of the money is spent on refrigeration, transport and profit for agents and supermarket chains. Local or hyper-local agriculture needs to bypass or circumvent these systems, and be connected more directly to the consumer. This is the interface. In hyper-localised systems effectiveness is often more important than efficiency, and direct links between producer and consumer create new economies.

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The linear and nonlinear properties of small-amplitude electron-acoustic solitary waves are investigated via the fluid dynamical approach. A three-component plasma is considered, composed of hot electrons, cold electrons, and ions (considered stationary at the scale of interest). A dissipative (wave damping) effect is assumed due to electron-neutral collisions. The background (hot) electrons are characterized by an energetic (excessively superthermal) population and are thus modeled via a κ-type nonthermal distribution. The linear characteristics of electron-acoustic excitations are discussed, for different values of the plasma parameters (superthermality index κ and cold versus hot electron population concentration β). Large wavelengths (beyond a threshold value) are shown to be overdamped. The reductive perturbation technique is used to derive a dissipative Korteweg de-Vries (KdV) equation for small-amplitude electrostatic potential disturbances. These are expressed by exact solutions in the form of dissipative solitary waves, whose dynamics is investigated analytically and numerically. Our results should be useful in elucidating the behavior of space and experimental plasmas characterized by a coexistence of electron populations at different temperatures, where electron-neutral collisions are of relevance.

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The blocking of ion transport at interfaces strongly limits the performance of electrochemical nanodevices for energy applications. The barrier is believed to arise from space-charge regions generated by mobile ions by analogy to semiconductor junctions. Here we show that something different is at play by studying ion transport in a bicrystal of yttria (9% mol) stabilized zirconia (YSZ), an emblematic oxide ion conductor. Aberration-corrected scanning transmission electron microscopy (STEM) provides structure and composition at atomic resolution, with the sensitivity to directly reveal the oxygen ion profile. We find that Y segregates to the grain boundary at Zr sites, together with a depletion of oxygen that is confined to a small length scale of around 0.5 nm. Contrary to the main thesis of the space-charge model, there exists no evidence of a long-range O vacancy depletion layer. Combining ion transport measurements across a single grain boundary by nanoscale electrochemical strain microscopy (ESM), broadband dielectric spectroscopy measurements, and density functional calculations, we show that grain-boundary-induced electronic states act as acceptors, resulting in a negatively charged core. Ultimately, it is this negative charge which gives rise to the barrier for ion transport at the grain boundary