1,152 research outputs found

    Computer-based materials: a study of learner autonomy and strategies

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    This paper reports on a study which examines the extent to which specified cognitive, social, and metacognitive strategies, are used by language students when working with computer-based materials (CBMs), in self-study contexts outside of the language classroom; particularly in a self-access centre (SAC). Data were collected using questionnaires, interviews and snap-shot observations from English as a Foreign Language (EFL) students enrolled on a summer course at a British Higher Education Institution (HEI). The data identify the frequency with which students use a SAC and the value they attach to computers for language learning. The data then examine the types of strategies students use and the extent to which learner autonomy is being fostered. The vast majority of participants were found to have positive attitudes towards computer-based material (CBMs) and language learning despite frequent use of L1, furthermore they were found to use cognitive strategies and to apply metacognitive awareness in their use of such CBMs. Students believed CBMs assisted with learning and demonstrated conscious applications of a range of strategies while learning in an electronic environment. However, the study also found that less than half the students used social strategies in the target language and this raises a number of issues

    Occupational therapy for the upper limb after stroke: implementing evidence-based constraint induced movement therapy into practice

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    Background Constraint induced movement therapy (CIMT), an intervention to increase upper limb (UL) function post-stroke, is not used routinely by therapists in the United Kingdom; reasons for this are unknown. Using the Promoting Action on Research Implementation in Health Services (PARIHS) framework to analyse CIMT research and context, a series of related studies explored implementation of CIMT into practice. Methods and Findings Systematic review: nineteen CIMT randomised controlled trials found evidence of effectiveness in sub-acute stroke, but could not determine the most effective evidence-based protocols. Further review of qualitative data found paucity of evidence relating to acceptability and feasibility of CIMT. Focus group: perceptions of the feasibility, including facilitators and barriers, of implementing CIMT into practice were explored in a group of eight therapists. Thematic analysis identified five themes: personal characteristics; setting and support; ethical considerations; education and training; and practicalities, which need to be addressed prior to implementation of CIMT. Mixed-methods, pilot study (three single cases): pre- and post-CIMT (participant preferred protocol) interviews explored perceptions and experiences of CIMT, with pre- and post-CIMT measurement of participation and UL function. Findings indicated: (i) provision of evidence-based CIMT protocols was feasible, although barriers persisted; (ii) piloted data collection and analysis methods facilitated exploration of stroke survivors’ perceptions and experiences, and recorded participation and UL function. Conclusions Findings traversed PARIHS elements (evidence, context, facilitation), and should be considered prior to further CIMT implementation. Future studies of CIMT should explore: effects of CIMT protocol variations; characteristics of stroke survivors most likely to benefit from CIMT; interactions between CIMT and participation

    Coarsening Dynamics of 2D Subaqueous Dunes

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    Abstract: Fluid flow over an initially flat granular bed leads to the formation of a surface‐wave instability. The sediment bed profile coarsens and increases in amplitude and wavelength as disturbances develop from ripples into dunes. We perform experiments and numerical simulations to quantify both the temporal evolution of bed properties and the relationship between the initial growth rate and the friction velocity u∗. Experimentally, we study underwater bedforms originating from a thin horizontal particle layer in a narrow and counter‐rotating annular flume. We investigate the role of flow speed, flow depth and initial bed thickness on dune evolution. Bedforms evolve from small, irregular disturbances on the bed surface to rapidly growing connected terraces (2D equivalent of transverse dunes) before splitting into discrete dunes. Throughout much of this process, growth is controlled by dune collisions which are observed to result in either coalescence or ejection (mass exchange). We quantify the coarsening process by tracking the temporal evolution of the bed amplitude and wavelength. Additionally, we perform Large Eddy Simulations (LES) of the fluid flow inside the flume to relate the experimental conditions to u∗. By combining the experimental observations with the LES results, we find that the initial dune growth rate scales approximately as u ∗ 5 u5{u}_{\ast }^{5} . These results can motivate models of finite‐amplitude dune growth from thin sediment layers that are important in both natural and industrial settings

    Understanding voltage decay in lithium-excess layered cathode materials through oxygen-centred structural arrangement

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    Lithium-excess 3d-transition-metal layered oxides (Li1+xNiyCozMn1-x-y-zO2, > 250 mAh g(-1)) suffer from severe voltage decay upon cycling, which decreases energy density and hinders further research and development. Nevertheless, the lack of understanding on chemical and structural uniqueness of the material prevents the interpretation of internal degradation chemistry. Here, we discover a fundamental reason of the voltage decay phenomenon by comparing ordered and cation-disordered materials with a combination of X-ray absorption spectroscopy and transmission electron microscopy studies. The cation arrangement determines the transition metal-oxygen covalency and structural reversibility related to voltage decay. The identification of structural arrangement with de-lithiated oxygen-centred octahedron and interactions between octahedrons affecting the oxygen stability and transition metal mobility of layered oxide provides the insight into the degradation chemistry of cathode materials and a way to develop high-energy density electrodes

    A Prospective Longitudinal Study of the Clinical Outcomes from Cryptococcal Meningitis following Treatment Induction with 800 mg Oral Fluconazole in Blantyre, Malawi

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    Introduction: Cryptococcal meningitis is the most common neurological infection in HIV infected patients in Sub Saharan Africa, where gold standard treatment with intravenous amphotericin B and 5 flucytosine is often unavailable or difficult to administer. Fluconazole monotherapy is frequently recommended in national guidelines but is a fungistatic drug compromised by uncertainty over optimal dosing and a paucity of clinical end-point outcome data. Methods: From July 2010 until March 2011, HIV infected adults with a first episode of cryptococcal meningitis were recruited at Queen Elizabeth Central Hospital, Blantyre, Malawi. Patients were treated with oral fluconazole monotherapy 800 mg daily, as per national guidelines. ART was started at 4 weeks. Outcomes and factors associated with treatment failure were assessed 4, 10 and 52 weeks after fluconazole initiation. Results: Sixty patients were recruited. 26/60 (43%) died by 4 weeks. 35/60 (58.0%) and 43/56 (77%) died or failed treatment by 10 or 52 weeks respectively. Reduced consciousness (Glasgow Coma Score ,14 of 15), moderate/severe neurological disability (modified Rankin Score .3 of 5) and confusion (Abbreviated Mental Test Score ,8 of 10) were all common at baseline and associated with death or treatment failure. ART prior to recruitment was not associated with better outcomes. Conclusions: Mortality and treatment failure from cryptococcal meningitis following initiation of treatment with 800 mg oral fluconazole is unacceptably high. To improve outcomes, there is an urgent need for better therapeutic strategies and point-of-care diagnostics, allowing earlier diagnosis before development of neurological deficit

    Capsular profiling of the Cronobacter genus and the association of specific Cronobacter sakazakii and C. malonaticus capsule types with neonatal meningitis and necrotizing enterocolitis

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    Background: Cronobacter sakazakii and C. malonaticus can cause serious diseases especially in infants where they are associated with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. Methods: This study used 104 whole genome sequenced strains, covering all seven species in the genus, to analyse capsule associated clusters of genes involved in the biosynthesis of the O-antigen, colanic acid, bacterial cellulose, enterobacterial common antigen (ECA), and a previously uncharacterised K-antigen. Results: Phylogeny of the gnd and galF genes flanking the O-antigen region enabled the defining of 38 subgroups which are potential serotypes. Two variants of the colanic acid synthesis gene cluster (CA1 and CA2) were found which differed with the absence of galE in CA2. Cellulose (bcs genes) were present in all species, but were absent in C. sakazakii sequence type (ST) 13 and clonal complex (CC) 100 strains. The ECA locus was found in all strains. The K-antigen capsular polysaccharide Region 1 (kpsEDCS) and Region 3 (kpsMT) genes were found in all Cronobacter strains. The highly variable Region 2 genes were assigned to 2 homology groups (K1 and K2). C. sakazakii and C. malonaticus isolates with capsular type [K2:CA2:Cell+] were associated with neonatal meningitis and necrotizing enterocolitis. Other capsular types were less associated with clinical infections. Conclusion: This study proposes a new capsular typing scheme which identifies a possible important virulence trait associated with severe neonatal infections. The various capsular polysaccharide structures warrant further investigation as they could be relevant to macrophage survival, desiccation resistance, environmental survival, and biofilm formation in the hospital environment, including neonatal enteral feeding tubes

    Honeybee Colony Vibrational Measurements to Highlight the Brood Cycle

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    Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time

    The effectiveness of tobacco control television advertisements in increasing the prevalence of smoke-free homes

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    BACKGROUND: There is considerable evidence that tobacco control mass media campaigns can change smoking behaviour. In the UK, campaigns over the last decade have contributed to declines in smoking prevalence and been associated with falls in cigarette consumption among continuing smokers. However, it is less evident whether such campaigns can also play a role in changing smokers’ behaviour in relation to protecting others from the harmful effects of their smoking in the home. We investigated whether exposure to English televised tobacco control campaigns, and specifically campaigns targeting second hand smoking, is associated with smokers having a smoke-free home. METHODS: We used repeated cross-sectional national survey data on 9872 households which participated in the Health Survey for England between 2004 and 2010, with at least one adult current smoker living in the household. Exposure to all government-funded televised tobacco control campaigns, and to those specifically with a second hand smoking theme, was quantified in Gross Rating Points (GRPs), an average per capita measure of advert exposure where 100 GRPs indicates 100 % of adults exposed once or 50 % twice. Our outcome was self-reported presence of a smoke-free home (where no one smokes in the home on most days). Analysis used generalised additive models, controlling for individual factors and temporal trends. RESULTS: There was no association between monthly televised campaigns overall and the probability of having a smoke-free home. However, exposure to campaigns specifically targeting second hand smoke was associated with increased odds of a smoke-free home in the following month (odds ratio per additional 100 GRPs, 1.07, 95 % CI 1.01 to 1.13), though this association was not seen at other lags. These effects were not modified by socio-economic status or by presence of a child in the home. CONCLUSIONS: Our findings provide tentative evidence that mass media campaigns specifically focussing on second hand smoke may be effective in reducing smoking in the home, and further evaluation of campaigns of this type is needed. General tobacco control campaigns in England, which largely focus on promoting smoking cessation, do not impact on smoke-free homes over and above their direct effect at reducing smoking

    Legacy iron and steel wastes in the UK: Extent, resource potential, and management futures

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    This is the author accepted manuscript. The final version is available on open access from Elsevier via the DOI in this recordThe iron and steel industry has a long tradition of bulk reuse of slags for a range of construction applications. Growing interest in recent years has seen slag resource recovery options extend to critical raw material recovery and atmospheric carbon capture. Full scale deployment of such technologies is currently limited in part by absent or partial inventories of slag deposit locations, data on composition, and volume estimates in many jurisdictions. This paper integrates a range of spatial information to compile a database of iron and steel slag deposits in mainland United Kingdom (UK) for the first time and evaluate the associated resource potential. Over 190 million tonnes of legacy iron and steel slag are present across current and former iron and steel working regions of the UK, with particular concentrations in the north west and north east of England, and central Scotland. While significant potential stockpiles of blast furnace and basic oxygen furnace slag could provide up to 0.9 million tonnes of vanadium and a cumulative carbon dioxide capture potential of 57–138 million tonnes, major management challenges for resource recovery are apparent. Over one third are located in close proximity to designated conservation areas which may limit resource recovery. Furthermore, land use analyses show that many of the sites have already been redeveloped for housing (nearly 30% urban cover). Deposits from recent decades in current or recently closed steel-working areas may have the greatest potential for resource recovery where such ambitions could be coupled with site restoration and regeneration efforts.Natural Environment Research Council (NERC)Engineering and Physical Sciences Research Council (EPSRC)Economic and Social Research Council (ESRC)UK Department for Business Energy and Industrial Strategy (BEIS
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