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Anita A. H. Verhoeven Peter M. Boendermaker Edzard J. Boerma Betty Meyboom-De Jong 《Health information and libraries journal》1999,16(3):141-150
The aim of this study was to develop a model to evaluate the retrieval quality of search queries performed by Dutch general practitioners using the printed Index Medicus, MEDLINE on CD-ROM, and MEDLINE through GRATEFUL MED. Four search queries related to general practice were formulated for a continuing medical education course in literature searching. The selected potential relevant citations from the course instructor and the 103 course participants together served as the basic set for the three judges to evaluate for (a) relevance and (b) quality, with the latter based on journal ranking, research design and publication type. Relevant individual citations received a citation quality score from 1 (low) to 4 (high). The overall search quality was expressed in a formula, which included the individual citation quality score of the selected and missed relevant citations, and the number of selected non-relevant citations. The outcome measures were the number and quality of relevant citations and agreement between the judges. Out of 864 citations, 139 were assessed as relevant, of which 44 citations received an individual citation quality score of 1, 76 of 2, 19 of 3 and none of 4. The level of agreement between the judges was 68% for the relevant citations, and 88% for the non-relevant citations. We describe a model for the evaluation of search queries based not only on the relevance, but also on the quality of the citations retrieved. With adaptation, this model could be generalized to other professional users, and to other bibliographic sources. 相似文献
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This study is an attempt to contribute to the growing body of knowledge about students' conceptions and views concerning environmental and natural resource issues. Answers have been sought to the following questions: “How do Swedish students in grade 9 (15–16 years old) and grade 12 (18–19 years old) explain the greenhouse effect?”, “How do they think reduction of CO2 emission would affect society?” and “How do they explain that the depletion of the ozone layer is a problem?” The method chosen to answer these questions was to give students written tasks of the open‐ended type. Five models of the greenhouse effect appear among the answers, all more or less incomplete, but nevertheless with potential for development. The students' responses also indicate that they do not fully understand what fundamental societal changes would occur as a result of a drastic reduction in CO2 emission. On the other hand, they are rather well informed about how injurious depletion of the ozone layer is to humans. The findings are discussed, including implications for teaching. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 1096–1111, 2000 相似文献
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Daniel P. Shepardson Anita Roychoudhury Andy Hirsch Dev Niyogi Sara M. Top 《Environmental Education Research》2014,20(3):333-353
Although many environmental and science educators have explored students’ conceptual understandings, misconceptions, and knowledge of the greenhouse effect, global warming, and climate change, few have investigated the ways students conceptualize climate as a system or how components of the system influence climate. Therefore, the purpose of this study was to begin the process of understanding how US students conceptualize a climate system. A total of 42 seventh grade students (ages 12–13) from the Midwest completed an open-response task. From the inductive analysis of student written responses, 22 codes emerged that reflected students’ conceptions of the climate system. From these codes, three path diagrams were constructed that illustrate these students’ conceptions about how a climate system influences climate and how greenhouse gases and global warming impact the climate system. A generalized model of students’ conception of a climate system was generated. Students in this study conceptualized a climate system in a unidirectional, linear, cause and effect relationship that emphasized the atmospheric component of the climate system. 相似文献
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Anderson C Stackhouse R Shaw A Iredale R 《Public understanding of science (Bristol, England)》2011,20(2):146-162
While there has been research conducted on public views about ethical and social aspects of the National DNA Database (NDNAD), there is little which focuses on views of young people, in particular those whose details are held on the NDNAD. We describe an engagement activity developed in South Wales to engage young offenders with ethical and social issues surrounding the NDNAD--a Mock Trial--and how we facilitated the presentation of their views to policy makers. We discuss the successes and challenges we encountered with engaging young offenders, decisions that the young people reached about possible future policies for the NDNAD at the Mock Trial, and their contribution to the decision-making process. 相似文献
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Sascha Meyer dos Santos Anita Zorn Zeno Guttenberg Bettina Picard-Willems Christina Kl?ffling Karen Nelson Ute Klinkhardt Sebastian Harder 《Biomicrofluidics》2013,7(5)
A universal coagulation test that reliably detects prolonged coagulation time in patients, irrespective of the anticoagulant administered, has not been available to date. An easily miniaturised, novel μ-fluidic universal coagulation test employing surface acoustic waves (SAW) is presented here. SAW was employed to instantly mix and recalcify 6 μl citrated whole blood and image correlation analysis was used to quantify clot formation kinetics. The detection of clinically relevant anticoagulant dosing with old anticoagulants (unfractionated heparin, argatroban) and new anticoagulants (dabigatran, rivaroxaban) has been tested and compared to standard plasma coagulation assays. The applicability of this novel method has been confirmed in a small patient population. Coagulation was dose-proportionally prolonged with heparin, argatroban, dabigatran, and rivaroxaban, comparable to standard tests. Aspirin and clopidogrel did not interfere with the SAW-induced clotting time (SAW-CT), whereas the strong GPIIb/IIIa-inhibitor abciximab did interfere. Preliminary clinical data prove the suitability of the SAW-CT in patients being treated with warfarin, rivaroxaban, or dabigatran. The system principally allows assessment of whole blood coagulation in humans in a point-of-care setting. This method could be used in stroke units, emergency vehicles, general and intensive care wards, as well as for laboratory and home testing of coagulation. 相似文献