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David B. Resnik Elizabeth Wager Grace E. Kissling 《Journal of the Medical Library Association》2015,103(3):136-139
Objective
This study gathered information about the retraction policies of the top 200 scientific journals, ranked by impact factor.Methods
Editors of the top 200 science journals for the year 2012 were contacted by email.Results
One hundred forty-seven journals (74%) responded to a request for information. Of these, 95 (65%) had a retraction policy. Of journals with a retraction policy, 94% had a policy that allows the editors to retract articles without authors’ consent.Conclusions
The majority of journals in this sample had a retraction policy, and almost all of them would retract an article without the authors’ permission. 相似文献126.
Jared Keengwe Grace Onchwari Joachim Agamba 《Education and Information Technologies》2014,19(4):887-898
Although rapid advances in technology has allowed for the growth of collaborative e-learning experiences unconstrained by time and space, technology has not been heavily infused in the activities of teaching and learning. This article examines the theory of constructivism as well as the design of e-learning activities using constructivist principles. The manner in which constructivist theory supports e-Learning is explored, and extrapolating from this pedagogical theory, some implications are provided to model effective practices of the characteristics and capacities of this powerful learning environment. 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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Grace M. Jackson-Brown 《The Reference Librarian》2017,58(2):136-151
This study is an exploratory qualitative investigation of academic library blogs with the purpose of examining how the technology of blogging is evolving for reference and research purposes at particular academic law libraries. This study uses anthropological archive research methods to study the blogs’ posts and triangulates the study with librarian blogger interviews. It provides a look into possible future directions for blogging in academic law libraries that may serve as a model for other academic libraries. 相似文献
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Tom Power Robina Shaheen Mike Solly Clare Woodward Sonia Burton 《Curriculum Journal》2013,24(4):503-529
In the Least Economically Developed Countries (LEDCs), School Based Teacher Development (SBTD) is sometimes advocated as a potential mechanism for improving the classroom practices experienced by millions of children in a complete school system, as quickly as possible. Robust evidence is required for approaches to be implemented with some confidence by Government development agencies, such as the UK Department for International Development (DFID). SBTD has a long history stemming from ideas of school-based curriculum development, which underlay the ideas on teacher-as-researcher, and is typically advocated in the developed world based on a view of the teacher as a professional. How might such notions play out, and to what effect, in LEDC contexts? This article examines the issues at stake in introducing SBTD in LEDCs, by examining: the nature of the evidence for various forms of teacher development, the nature of SBTD in particular and the evidence for its effectiveness. The latter issues will be illustrated through examination of English in Action (EIA, www.eiabd.com), a large-scale SBTD programme for primary and secondary English language (EL) teachers serving government schools across Bangladesh. 相似文献