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The authors give a critical survey of the model of communicative competence underlying van Ek's Scope and Levels, written for the Council of Europe as a follow‐up of The Threshold Level of 1975‐76. Although generally in favour of van Ek's new approach, the authors find that van Ek's model lacks breadth of definition of strategic competence. This leads to some unclarity and confusion in van Ek's proposals. The authors also regret that van Ek does not allot a greater role to compensatory strategies in the assessment of levels of language command.
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This article argues that an enlightened, inclusive vision of universal service is possible by learning lessons from disability. Telecommunications policy has historically built in norms that needlessly exclude people who are regarded as having a disability and therefore being outside of the mainstream. Accordingly, universal service policies focus on availability and affordability of telecommunications services, rather than on their accessibility and functionality. The article shows how rethinking universal service through disability can lead to inclusive policies that benefit everybody. 相似文献
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Giraud G Pethig R Schulze H Henihan G Terry JG Menachery A Ciani I Corrigan D Campbell CJ Mount AR Ghazal P Walton AJ Crain J Bachmann TT 《Biomicrofluidics》2011,5(2):24116
The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ~0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices. 相似文献
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ABSTRACTFantastic Man (2014) and Searching for Sugar Man (2012) mobilize tropes of discovery occurring in the filmed process of collecting and curating the work and identities of two reluctant, elusive, and resistive figures. These documentaries are part of a discourse of collectability marked by the urge to discover and narrate a “quest” that has its precedents in record collecting as obsessive cultural practice and in the fetishizing of obscurity. Furthermore, they can be seen as “performances” of the artiste and repertoire (A&R) process but for a “post-rock” era in which the customary roles of A&R have largely been eclipsed by social, economic, and technological changes to the music industry: the “(re-)discovery” of Onyeabor and Rodriguez exemplifies an increasingly common fusion of, rather than oscillation between, novelty and nostalgia in the music industry, as “old” artists are “newly” discovered through practices of media archaeology aimed at unearthing artifacts of cultural and economic value from an ever bigger and denser digital archive. 相似文献
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Michael S. Stinson Marcia J. Scherer Gerard G. Walter 《Research in higher education》1987,27(3):244-258
A study of attrition after the first year of college was conducted with the 1984 entry class of the National Technical Institute for the Deaf. A path-analytic model of 9 factors affecting student persistence was tested using LISREL (N = 233). The results indicate that social integration is an important factor in college persistence. Grade point average is not a critical factor in first year attrition. While provocative, the reasons behind these findings may be specific to NTID. For example, many students come to NTID specifically for its social community. It is concluded, therefore, that while these results were somewhat different from those of studies with hearing students, they support the proposition that studies of college attrition cannot be generalized across institutions. 相似文献
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Gerard Salton 《Information processing & management》1985,21(3):260-261
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