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131.
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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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   
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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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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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How generalizable are the scores from performance-based assessments? How can we best increase the gener-alizability of results? What level of generalizability is needed for different testing purposes?  相似文献   
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