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1.
Jane Harrison 《Health information and libraries journal》1997,14(1):33-42
Thepractice of evidence-based health care requires that information on methodology be identifiedfrom databases such as MEDLINE. Up until this year there have been no designated medicalsubject headings (MeSH) for evidence-based health care. ‘EVIDENCE-BASEDMEDICINE’ appears as a MeSH term from 1997. The absence of designated MeSH forthis concept prior to 1997 provides a challenge to the searcher. This paper describes the creationof a MEDLINE search strategy to retrieve articles on the methods of evidence-based health carepublished prior to the introduction of the new term, where an optimal combination of free-textand MeSH terms is required to identify relevant material. The study examines both free-text andsubject heading searching and attempts an optimal balance of sensitivity and specificity. It beginsby examining separate free-text and subject heading searches. Sensitivity of the subject headingsearch was 33% and specificity 80%, while the free-text search produced asensitivity of 50% and a specificity of 67%. The final strategy, combining bothapproaches, was more successful with sensitivity reaching between 82 and 90% andspecificity 83%. It is therefore possible to devise a search strategy to retrieve articles on themethods of evidence-based health care with relatively successful rates of sensitivity andspecificity. The limitations of MEDLINE, however, necessitate the use of additional approachesin identifying articles on the methods of evidence-based health care. 相似文献
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Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry
Zachary E. Voras Kristin deGhetaldi Brian Baade Eric Gordon Glenn Gates Thomas P. Beebe 《文物保护研究》2016,61(4):222-235
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni. 相似文献
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There is an ongoing debate in the student evaluation of teaching literature about whether an overall rating or factorial dimensions of teaching effectiveness should be used in personnel decisions. Marsh and his colleagues have advocated the use of a weighted average approach to computing overall evaluations. A policy-capturing experiment was carried out where students in three different instructional contexts made overall evaluations of hypothetical instructors based on a manipulation of the teaching factors in Marsh's SEEQ. The results indicated (1) amount learned was consistently the most important factor affecting overall evaluations; (2) course difficulty was consistently the least important factor affecting overall evaluations; and (3) there was a strong similarity among the three groups in the relative importance of the various teaching factors in arriving at an overall evaluation. The implications of this research are discussed, as well as directions for future research. 相似文献
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Amanda Harrison Megan Phelps Arany Nerminathan Shirley Alexander Karen M. Scott 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(2):531-545
University policies prohibiting use of mobile devices by medical students during clinical placements are contradicted by regular use by physicians. Consequently, many students use their mobile devices, which can be beneficial for learning but may put patient privacy at risk. This study explores the reasons underlying students' decisions about using mobile devices in clinical settings. We used a mixed-methods sequential explanatory design involving a questionnaire and focus groups. Qualitative data from the questionnaire and focus groups was analysed through thematic analysis. We found students were aware of the risks mobile devices posed to professionalism and medical practice. Despite prohibitions, many made individual decisions to use mobile devices because the benefits outweighed the risks. These students were influenced by an organised, strategic approach to learning and a motivation to comply with the beliefs and behaviours of their medical teams and conform to physicians' directives in order to participate in their community of practice. Many students appear to be transferring everyday use of mobile devices to clinical settings. There is a need to understand and promote aspects of learning that are enhanced by mobile devices in clinical settings, while articulating clear guidelines and boundaries compatible with the professional behaviour expected of students. 相似文献
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John Warmenhoven Stephen Cobley Conny Draper Andrew Harrison Norma Bargary Richard Smith 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(3):317-341
The proliferation of new biomechanical technology in laboratory and field settings facilitates the capture of data-sets consisting of complex time-series. An understanding of the appropriate statistical approaches for analysing and interpreting these data-sets is required and the functional data analysis (FDA) family of statistical techniques has emerged in the biomechanical literature. Given the use of FDA is currently in its infancy with biomechanical data, this paper will form the first of a two part series aiming to address practical issues surrounding the application of FDA techniques in biomechanics. This work focuses on functional principal components analysis (fPCA), which is explored using existing literature and sample data from an on-water rowing database. In particular methodological considerations for the implementation of fPCA such as temporal normalisation of data, removal of unwanted forms of variation in a data-set and documented methods for preserving the original temporal properties within a set of curves are explored in detail as a part of this review. Limitations and strengths of the technique are outlined and recommendations are provided to encourage the appropriate use of fPCA within the field of applied sports biomechanics. 相似文献
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This study was an initial attempt to investigate the relationships among self-efficacy, outcome expectancy, behavioral intention, and actual behavior over time in a beginning weight training class. A total of 109 participants completed questionnaires assessing their self-efficacy, outcome expectancy, and intentions for future weight training. Their attendance and workout logs were calculated as a measure of actual behavior. Correlation analyses revealed significant positive relationships among all the variables during both program periods. Multiple regression analyses indicated that outcome expectancy initially played a more important role than self-efficacy in predicting behavioral intention and actual behavior. However, self-efficacy appeared more influential at midprogram. Findings of this study can enhance our understanding of the determining factors for individuals' motivated behaviors in college physical activity classes. 相似文献
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