947 resultados para The discourse of critical


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The chlorophyll fluorescence kinetics of marine red alga Grateloupia turutunt Yamada, green alga Ulva pertusa Kjellm and brown alga Laminaria japonica Aresch during natural sustained dehydration were monitored and investigated. The pulse amplified modulation (PAM) system was used to analyze the distinct fluorescence parameters during thallus dehydration. Results proved that the fluorescence kinetics of different seaweed all showed three patterns of transformation with sustained water loss. These were: 1) peak kinetic pattern (at the early stage of dehydration fluorescence enhanced and quenched subsequently, representing a normal physiological state). 2) plateau kinetic pattern (with sustained water loss fluorescence enhanced continuously but quenching became slower, finally reaching its maximum). 3) Platform kinetic pattern (fluorescence fell and the shape of kinetic curve was similar to plateau kinetic pattern). A critical water content (CWC) could be found and defined as the percentage of water content just prior to the fluorescence drop and to be a significant physiological index for evaluation of plant drought tolerance. Once thallus water content became lower than this value the normal peak pattern can not be recovered even through rehydration, indicating an irreversible damage to the thylakoid membrane. The CWC value corresponding to different marine species were varied and negatively correlated with their desiccation tolerance, for example. Laminaria japonica had the highest CWC value (around 90%) and the lowest dehydration tolerance of the three. In addition, a fluorescence "burst" was found only in red algae during rehydration. The different fluorescence parameters F-o, F-v and F-v, F-m were measured and compared during water loss. Both F-o and F-v increased in the first stage of dehydration but F-v/F-m. kept almost constant. So the immediate response of in vivo chlorophyll fluorescence to dehydration was an enhancement. Later with sustained dehydration F-o increased continuously while F-v decreased and tended to become smaller and smaller. The major changes in fluorescence (including fluorescence drop during dehydration and the burst during rehydration) were all attributed to the change in F-o instead of F-v This significance of F-o indicates that it is necessary to do more research on F-o as well as on its relationship with the state of thylakoid membrane.

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Instrumental music education is provided as an extra-curricular activity on a fee-paying basis by a small number of Education and Training Boards, formerly Vocational Education Committees (ETB/VECs) through specialist instrumental Music Services. Although all citizens’ taxes fund the public music provision, participation in instrumental music during school-going years is predominantly accessed by middle class families. A series of semistructured interviews sought to access the perceptions and beliefs of instrumental music education practitioners (N=14) in seven publicly-funded music services in Ireland. Canonical dispositions were interrogated and emergent themes were coded and analysed in a process of Grounded theory. The study draws on Foucault’s conception of discourse as a lens with which to map professional practices, and utilises Bourdieu’s analysis of the reproduction of social advantage to examine cultural assumptions, which may serve to privilege middle-class cultural choice to the exclusion of other social groups. Study findings show that within the Music Services, aesthetic and pedagogic discourses of the 19th century Conservatory system exert a hegemonic influence over policy and practice. An enduring ‘examination culture’ located within the Western art music tradition determines pedagogy, musical genre, and assessment procedures. Ideologies of musical taste and value reinforce the more tangible boundaries of fee-payment and restricted availability as barriers to access. Practitioners are aware of a status duality whereby instrumental teachers working as visiting specialists in primary schools experience a conflict between specialist and generalist educational aims. Nevertheless, study participants consistently advocated siting the point of access to instrumental music education in the primary schools as the most equitable means of access to instrumental music education. This study addresses a ‘knowledge gap’ in the sociology of music education in Ireland. It provides a framework for rethinking instrumental music education as equitable in-school musical participation. The conclusions of the study suggest starting-points for further educational research and may provide key ‘prompts’ for curriculum planning.

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This paper explores certain pragmatic features of advertising discourse. It focuses on and expands upon a binary distinction between types of advertising discourse which was proposed initially by Bernstein (1974) and which has been touched upon more recently by other commentators such as Cook (1992). This is the distinction between reason advertisements (those which suggest a motive or reason for purchase) and tickle advertisements (those which appeal to humour, emotion and mood). It will be argued that Bernstein's distinction can be accommodated relatively systematically within contemporary frameworks of language and discourse. Drawing on a range of work in pragmatics and in systemic-functional linguistics, this paper takes some tentative steps towards the development of a theoretical model with accounts for this particular communicative-cognitive dimension of advertising discourse.

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This article draws on a range of models from language studies, particularly from linguistic pragmatics, in order to elucidate patterns in the production and reception of irony in its social and cultural context. An expanded view of the concept of irony, it is suggested, allows for better modelling of the creative mechanisms which underpin it, and in doing so can open the way for a fuller understanding of humour production and reception. A consequence of this broader (five-fold) typology of irony is that it can help shed light on the cultural dynamic of irony. The article uses a range of examples from different media and the lay definitions and interpretations that ordinary (non-academic) users of the language use in the comprehension of irony. Insofar as it seeks to develop an overarching model of irony, this paper draws on a variety of textual examples from a variety of sources, ranging from corpus evidence, through a stand-up comedy routine, to political wall murals and their discursive re-conformation as humour in present-day Northern Ireland. Although the central discussion is supported by insights from other linguistic, cognitive and socio-cultural approaches, the theoretical framework which emerges, with its focus on language and communication in context, is situated squarely within contemporary linguistic pragmatics.

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This research was prompted by the developing political discourse proposing the teaching of Britishness and British values in the context of the United Kingdom. This discourse will be reviewed in the first part of the article, in the context of previous work which has sought to assess how Britishness and related concepts might be promoted through education. The second part will be based on questionnaire responses from a sample of students following post-graduate initial teacher training programmes in a number of higher education partnerships. It indicates that, while political discourse and educational policy have sensitised trainee teachers to the agenda, there remains a deep uncertainty and misgiving about this as an educational objective.