421 research outputs found

    Contribution of nitrification and denitrification to N2O emissions from urine patches

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    Urine deposition by grazing livestock causes an immediate increase in nitrous oxide (N2O) emissions, but the responsible mechanisms are not well understood. A nitrogen-15 (15N) labelling study was conducted in an organic grass-clover sward to examine the initial effect of urine on the rates and N2O loss ratio of nitrification (i.e. moles of N2O-N produced per moles of nitrate produced) and denitrification (i.e. moles of N2O produced per moles of N2O + N2 produced). The effect of artificial urine (52.9 g N m-2) and ammonium solution (52.9 g N m-2) was examined in separate experiments at 45 and 35% water-filled pore space (WFPS), respectively, and in each experiment a water control was included. The N2O loss derived from nitrification or denitrification was determined in the field immediately after application of 15N-labelled solutions. During the next 24 h, gross nitrification rates were measured in the field, whereas the denitrification rates were measured in soil cores in the laboratory. Compared with the water control, urine application increased the N2O emission from 3.9 to 42.3 μg N2O-N m-2 h-1, whereas application of ammonium increased the emission from 0.9 to 6.1 μg N2O-N m-2 h-1. In the urine-affected soil, nitrification and denitrification contributed equally to the N2O emission, and the increased N2O loss resulted from a combination of higher rates and higher N2O loss ratios of the processes. In the present study, an enhanced nitrification rate seemed to be the most important factor explaining the high initial N2O emission from urine patches deposited on well-aerated soils

    Preparative fractionation of a random copolymer (SAN) with respect to either chain length or chemical composition

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    The possibilities to fractionate copolymers with respect to their chemical composition on a preparative scale by means of the establishment of liquid/liquid phase equilibria were studied for random copolymers of styrene and acrylonitrile (san). Experiments with solutions of san in toluene have shown that fractionation does in this quasi-binary system, where demixing results from marginal solvent quality, take place with respect to the chain length of the polymer only. On the other hand, if phase separation is induced by a second, chemically different polymer one can find conditions under which fractionation with respect to composition becomes dominant. This opportunity is documented for the quasi-ternary system dmac/san/polystyrene, where the solvent dimethyl acetamide is completely miscible with both polymers. The theoretical reasons for the different fractionation mechanisms are discussed

    RESPOND – A patient-centred program to prevent secondary falls in older people presenting to the emergency department with a fall: Protocol for a multi-centre randomised controlled trial

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    Introduction: Participation in falls prevention activities by older people following presentation to the Emergency Department (ED) with a fall is suboptimal. This randomised controlled trial (RCT) will test the RESPOND program which is designed to improve older persons’ participation in falls prevention activities through delivery of patient-centred education and behaviour change strategies. Design and setting: An RCT at two tertiary referral EDs in Melbourne and Perth, Australia. Participants: Five-hundred and twenty eight community-dwelling people aged 60-90 years presenting to the ED with a fall and discharged home will be recruited. People who: require an interpreter or hands-on assistance to walk; live in residential aged care or >50 kilometres from the trial hospital; have terminal illness, cognitive impairment, documented aggressive behaviour or history of psychosis; are receiving palliative care; or are unable to use a telephone will be excluded. Methods: Participants will be randomly allocated to the RESPOND intervention or standard care control group. RESPOND incorporates: (1) home-based risk factor assessment; (2) education, coaching, goal setting, and follow-up telephone support for management of one or more of four risk factors with evidence of effective intervention; and (3) healthcare provider communication and community linkage delivered over six months. Primary outcomes are falls and fall injuries per-person-year. Discussion: RESPOND builds on prior falls prevention learnings and aims to help individuals make guided decisions about how they will manage their falls risk. Patient-centred models have been successfully trialled in chronic and cardiovascular disease however evidence to support this approach in falls prevention is limited. Trial registration. The protocol for this study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12614000336684)

    Online interventions to prevent mental health problems implemented in school settings: the perspectives from key stakeholders in Austria and Spain

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    Background: Schools are key settings for delivering mental illness prevention in adolescents. Data on stakeholders’ attitudes and factors relevant for the implementation of Internet-based prevention programmes are scarce. Methods: Stakeholders in the school setting from Austria and Spain were consulted. Potential facilitators (e.g. teachers and school psychologists) completed an online questionnaire (N=50), policy makers (e.g. representatives of the ministry of education and health professional associations) participated in semi-structured interviews (N=9) and pupils (N=29, 14–19 years) participated in focus groups. Thematic analysis was used to identify experiences with, attitudes and needs towards Internet-based prevention programmes, underserved groups, as well as barriers and facilitators for reach, adoption, implementation and maintenance. Results: Experiences with Internet-based prevention programmes were low across all stakeholder groups. Better reach of the target groups was seen as main advantage whereas lack of personal contact, privacy concerns, risk for misuse and potential stigmatization when implemented during school hours were regarded as disadvantages. Relevant needs towards Internet-based programmes involved attributes of the development process, general requirements for safety and performance, presentation of content, media/tools and contact options of online programmes. Positive attitudes of school staff, low effort for schools and compatibility to schools’ curriculum were seen as key factors for successful adoption and implementation. A sound implementation of the programme in the school routine and continued improvement could facilitate maintenance of online prevention initiatives in schools. Conclusions: Attitudes towards Internet-based mental illness prevention programmes in school settings are positive across all stakeholder groups. However, especially safety concerns have to be considered

    Is the use of videotape recording superior to verbal feedback alone in the teaching of clinical skills?

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    <p>Abstract</p> <p>Background</p> <p>In recent times, medical schools have committed to developing good communication and history taking skills in students. However, there remains an unresolved question as to which constitutes the best educational method. Our study aims to investigate whether the use of videotape recording is superior to verbal feedback alone in the teaching of clinical skills and the role of student self-assessment on history taking and communication skills.</p> <p>Methods</p> <p>A randomized controlled trial was designed. The study was conducted with 52 of the Dokuz Eylul University Faculty of Medicine second year students. All students' performances of communication and history taking skills were assessed twice. Between these assessments, the study group had received both verbal and visual feedback by watching their video recordings on patient interview; the control group received only verbal feedback from the teacher.</p> <p>Results</p> <p>Although the self-assessment of the students did not change significantly, assessors' ratings increased significantly for videotaped interviews at the second time.</p> <p>Conclusions</p> <p>Feedback based on videotaped interviews is superior to the feedback given solely based on the observation of assessors.</p

    Conviviality and Parallax in David Olusoga’s Black and British: A Forgotten History

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    Through examining the BBC television series, Black and British: A Forgotten History, written and presented by the historian David Olusoga, and in extending Paul Gilroy’s assertion that the everyday, banality of living with difference is now an ordinary part of British life, this article considers how Olusoga’s historicization of the black British experience reflects a convivial rendering of UK multiculture. In particular, when used alongside Žižek’s notion of parallax, it is argued that understandings of convivial culture can be supported by a historical importance that deliberately ‘shocks’ and, subsequently dislodges, popular interpretations of the UK’s ‘white past’. Notably, it is parallax which puts antagonism, strangeness and ambivalence at the heart of contemporary depictions of convivial Britain, with the UK’s cultural differences located in the ‘gaps’ and tensions which characterize both its past and present. These differences should not be feared but, as a characteristic part of our convivial culture, should be supplemented with historical analyses that highlight but, also, undermine, the significance of cultural differences in the present. Consequently, it is suggested that if the spontaneity of conviviality is to encourage openness, then, understandings of multiculturalism need to go beyond reification in order to challenge our understandings of the past. Here, examples of ‘alterity’ are neither ‘new’ nor ‘contemporary’ but, instead, constitute a fundamental part of the nation’s history: of the ‘gap’ made visible in transiting past and present
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