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Objective:This study compares two maps of biomedical sciences using Medical Subject Headings (MeSH) term co-assignments versus MeSH terms of citing/cited articles and reveals similarities and differences between the two approaches.Methods:MeSH terms assigned to 397,475 journal articles published in 2015, as well as their 4,632,992 cited references, were retrieved from Web of Science and MEDLINE databases, respectively, which formed over 7 million MeSH co-assignments and nearly 18 million direct citation pairs. We generated six network visualizations of biomedical science at three levels using Gephi software based on these MeSH co-assignments and citation pairs.Results:The MeSH co-assignment map contained more nodes and edges, as MeSH co-assignments cover all medical topics discussed in articles. By contrast, the MeSH citation map contained fewer but larger nodes and wider edges, as citation links indicate connections to two similar medical topics.Conclusion:These two types of maps emphasize different aspects of biomedical sciences, with MeSH co-assignment maps focusing on the relationship between topics in different categories and MeSH direct citation maps providing insights into relationships between topics in the same or similar category.  相似文献   
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研究目的:二氧化钛(TiO2)纳米颗粒已经广泛应用于化妆品、防晒霜、涂料和牙膏等。这些纳米颗粒性质非常稳定,能在废水和生物固体中转移和分散。现有研究表明,TiO2纳米颗粒对动物正常生理活动具有毒性等负面作用。但是,它们对植物是否具有毒性特别是是否会产生植物基因毒性至今尚不清楚。因此,本文使用随机扩增多态性DNA技术研究TiO2纳米颗粒是否对西葫芦具有基因毒性,为TiO2纳米颗粒排放进入环境后的潜在植物毒性风险评价提供依据。 创新要点:首次发现了TiO2纳米颗粒对西葫芦具有基因毒性。 重要结论:采用随机扩增多态性DNA技术,发现TiO2纳米颗粒污染处理的西葫芦样品与未处理样品的基因组DNA图谱相比,不仅在谱带强度有明显差异,而且存在谱带消失和新谱带产生现象,表明TiO2纳米颗粒对西葫芦具有基因毒性。  相似文献   
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Many publishers of medical journals actively court coverage by the news media. However, the extent and effect of these practices are poorly understood. After reviewing prior literature regarding the impact of news coverage on the citation rate of journal articles, this paper seeks to measure the extent to which medical journals with clinical significance use public relations practices to encourage news coverage of their articles, and the success that those practices had in increasing coverage by newspapers. Editors of 120 medical journals published worldwide with clinical relevance were surveyed; the response rate was 54%. Eighty per cent of respondents reported that their journal offered journalists at least one of press releases, access to full‐text articles, or press conferences. Editors whose journals used the practices in conjunction with an embargo reported higher‐quality news coverage than editors of journals that did not, but editors and journalists held differing views about the justifications for the specific practice known as an embargo.  相似文献   
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The podcast has recently emerged as a popular medium for comedians. It would not be accurate to describe the podcast as a wholly new, liberating medium that dispenses of all commercial logic in favor of the truly authentic, but it would be equally disingenuous to discount the feelings of empowerment and personal stability that the podcast medium has initiated for these comedians. Since April 2011, Paul Gilmartin, a stand-up comedian, television show host, and actor has hosted the Mental Illness Happy Hour (MIHH), a self-help podcast for those suffering from depression, anxiety, and frustration. Gilmartin's podcast has attracted over a million listeners since it debuted and has inspired a devoted following, thriving message board, and the sort of unexpected career revival that surprised even Gilmartin himself. While the man behind the microphone might be a comedian, MIHH is sobering, reflective, and unvarnished in its earnestness. I argue that the constitution of audience within this podcast disrupts more conventional understandings of fan–celebrity interaction. It tests previously held assumptions and makes ambiguous the lines between performer and audience, audience, and self-help community.  相似文献   
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The current study reports on the process of developing a self-assessment instrument for vocational education students’ generic working life competencies. The instrument was developed based on a competence framework and in close collaboration with several vocational education teachers and intermediary organisations offering various human resource services. A first version of the questionnaire was presented to 26 students and 5 recent graduates who were asked to comment on the items. The pilot version of the questionnaire was completed by 826 students. Half of the data were used to explore the structure of the questionnaire (n?=?413) and the other half were used to confirm the structure (n?=?413). The results showed that 8 factors could be distinguished. Further analysis reduced this to 7 usable factors: empathy, listening, assertiveness, professional attitude, problem solving, cooperation ability and, planning and prioritising. The revised questionnaire containing 44 items was tested a second time to determine the stability and measurement invariance of the instrument. In total, 456 students from the first sample completed the questionnaire. The structure was confirmed and measurement invariance across students with and without working experience was established.  相似文献   
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Organizations must innovate if they are to survive in today's fiercely competitive marketplace. In this paper, we explore how leading organizations are using emerging technologies to enable novel forms of ideation that can radically increase the sheer volume of ideas they explore. In addition, we outline how organizations use technologies to cost effectively manage this increased volume of ideas by optimizing generation, mobilization, advocacy and screening, experimentation, commercialization, and even the diffusion and implementation of ideas. Critical to this is the management of knowledge during the innovation process.  相似文献   
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