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Objective: To determine whether information retrieval might be enhanced by making each component of a structured abstract a separately searchable field. Design: Parallel searches on records arranged so that each abstract could either be searched in its entirety or as a collection of structured fields. Subjects: Records about cardiovascular disease downloaded from MEDLINE and tested against clinical questions derived from a concurrent survey of CD-ROM use in three health science libraries. Intervention: The investigators identified terms used to structure abstracts on MEDLINE and imported the abstracts into an Idealist database prior to searching using keywords from clinical questions. Measurements and main results: recall and precision rates are given for each question in the ‘structured’ and the ‘unstructured’ set of records. Conclusions: Use of structured, rather than unstructured, abstracts improves precision at the ex-pense of recall and places heavier demands upon the searcher’s skill in choosing the correct fields within the abstract to search. Further investigation requires more accurate simulation of MEDLINE software that utilizes features such as MeSH terms, explode, facilities and delimiters. 相似文献
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1 Introduction New technologies and other developments haye changedthe information seeking behaviors of the academic communityand the general public.Nowhere is this more evident than inthe exponential growth of the World Wide Web and cellularphone usage.Responding to these user needs and newtechnologies,libraries are moving from being InformationWarehouses to becoming Information Portals.Full-text 相似文献
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Controversy concerning the issue of homosexual rights and practiceshas intensified in Britain over the last decade. Despite thisincrease in intensity, however, the question of mass publicopinion in relation to homosexual rights and practices has receivedalmost no empirical investigation. In an effort to remedy thissituation, this article focuses on both the role of respondents'gender as well as their perceptions concerning the gender ofparticipants in a homosexual relationship (both sexes versusgay men) in distinguishing their attitudes toward the publicacceptance of homosexuals and the adoption rights of lesbiansand gay men. Using nationally representative data from the BritishSocial Attitudes Surveys, we found that, whereas both respondents'gender and the gender of participants in a homosexual relationshipdemonstrated a significant influence on attitudes toward thepublic acceptance of homosexuals, they were unrelated to theadoption rights of lesbians or gay men. Even in relation tothe public acceptance of homosexuals, however, gender was notthe only, or even the most important, attribute in distinguishingindividual opinion in this instance. Other stronger and moreconsistent influences were education, age, and attitudes towardeither pre-marital or extra-marital sexual relations. The implicationsof these findings for both policy makers and homosexual activistsare discussed. 相似文献
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Validating the Willingness to Self-Censor Scale: Individual Differences in the Effect of the Climate of Opinion on Opinion Expression 总被引:1,自引:0,他引:1
Hayes Andrew F.; Glynn Carroll J.; Shanahan James 《Int. Journal of Public Opinion Research》2005,17(4):443-455
Hayes, Glynn, and Shanahan (2005) defined self-censorship asthe withholding of ones opinion around an audience perceivedto disagree with that opinion. They argued that people differin their willingness to self-censor and introduced an 8-itemself-report instrument, the Willingness to Self-Censor scale,to measure this individual difference. The results of an experimentalstudy presented here provide further evidence of the constructvalidity of the scale. Each participant in the study was presentedwith a hypothetical scenario that contained information suggestinga group of people the participant was conversing with abouta controversial topic held opinions that were either uniformlysimilar to or different from the participants own opinion.Four weeks prior, each participant had responded to the Willingnessto Self-Censor scale and a measure of dispositional shyness.As expected, the manipulation of the climate of opinion affectedwillingness to express an opinion to the group, but more soamong those who scored relatively high on the Willingness toSelf-Censor scale. These results support the notion that somepeople rely on information about the climate of opinion moreso than do others when they decide whether or not to voice theiropinion publicly, and they suggest that the Willingness to Self-Censorscale measures this individual difference. 相似文献
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ABSTRACTControl of relative humidity (RH) for collections care is challenging in U.K. historic houses because they are often highly ventilated with poor heat retention, a porous building fabric and naturally tend to high (60–80%) RH if unheated. The significance of the building means that large-scale modifications and installation of air handling systems may be unfeasible and undesirable for the conservation of the building. In the late 1980s the National Trust, for English, Wales and Northern Ireland, investigated conservation heating as an RH control method that works with the natural environment of historic buildings, mimicking historic heating and requiring only modification of existing heating services or a light touch installation of new heating systems. The National Trust adopted conservation heating as its preferred method for environmental control in historic buildings from the 1990s. This method was presented at the IIC 1994 Ottawa congress on preventive conservation. Conservation heating has since been adopted by many historic house management organisations, particularly across north-west Europe, where it is well suited to the climate. This paper reviews conservation heating developments implemented by the National Trust since 1994, in response to a changing external context, new knowledge and developments in operational practice. 相似文献
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This research analyzed a dataset of academic libraries' posts on Facebook. It applied a text and data analytics approach to a dataset collected from the Facebook posts of academic libraries at the top 100 English-speaking universities, as listed by the 2014 Shanghai World University Rankings. The dataset is from a two-year posting history of 18,333 unique posts, 113,621 likes, and 3401 comments. Less than a quarter of the libraries had more than 2000 post-related likes, and only seven received more than 100 comments on their postings. Content analysis identified the most prevalent single word (unigrams), bigrams (two-word sequences), and trigrams (three-word sequences) in high and low engagement content. Semantic analysis identified the semantic categories for posts with high and low engagement. The findings can assist academic libraries in their social media strategies for engagement, marketing, and visibility. 相似文献
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Increased genetic testing in personalized medicine presents unique challenges for couples, including managing disease risk and potential discrimination as a couple. This study investigated couples’ conflicts and support gaps as they coped with perceived genetic discrimination. We also explored the degree to which communal coping was beneficial in reducing support gaps and ultimately stress. Dyadic analysis of married adults (N?=?266, 133 couples), in which one person had the genetic risk for serious illness, showed that perceived discrimination predicted more frequent conflicts about alpha-1 antitrypsin deficiency-related treatment, privacy boundaries, and finances, which, in turn, predicted wider gaps in emotion and esteem support, and greater stress for both spouses. Communal coping predicted lower support gaps for both partners and marginally lower stress. 相似文献