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231.
The growth of archival studies programs has prompted archival scholars to establish an international network for supporting collaborative research, curriculum development, and pedagogy. Doctoral education is key to the sustainability of such programs and the continuation of the network over time. We carried out longitudinal research to survey the population of doctoral students attending one or more Archival Education and Research Institutes (AERI), an annual meeting first held in 2009. Building on prior research on graduate archival education, we gathered demographic and qualitative data about doctoral students specializing in archival studies who are based in several countries including the USA. We sought to assess attendee motivations, guide conference planning, and help advance overall AERI objectives. Our study provides a baseline understanding of the disciplinary backgrounds, research directions, and specific professional development activities that doctoral students in archival studies pursued around the globe from 2013 to 2015. This paper argues that doctoral education should continue to be a particular subject of archival research and indicates how archival students’ range of academic interests is diversifying and strengthening the scholarly community. 相似文献
232.
Daniel Maier A. Waldherr P. Miltner G. Wiedemann A. Niekler A. Keinert 《Communication methods and measures》2018,12(2-3):93-118
ABSTRACTLatent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project. 相似文献
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This article explores the existence of a “citizen-centered journalism” that sees citizens as crucial participants in the construction of news and as co-creators of their own worlds. Through qualitative case studies of three news organizations, the article examines the motivation for using a citizen-centered approach, the news routines that are required to do so, the categories of content produced, and the perceived impact of this approach. The results suggest these news organizations are working in partnership with communities and striving to give a voice to historically marginalized communities. The journalists, however, see citizen participation as complementary to professional journalistic routines that favor verifiable information, rather than assigning inherent value to it for its own sake. 相似文献
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Yi-Feng Wang Chunqiu Zhang Keni Yang Yufei Wang Shaobo Shan Yan Yan Kenneth A Dawson Chen Wang Xing-Jie Liang 《国家科学评论(英文版)》2021,8(6):17-27
Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new ‘biological identity’ and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells. Here, we employed home-made aggregation-induced-emission-visualized nanoliposomes TR4@Lipo as a model to investigate transportation with or without the protein corona by optical imaging techniques. The results show that the protein corona can change the cellular transportation mechanism of TR4@Lipo from energy-independent membrane fusion to energy-dependent endocytosis. The protein corona also modulates the intracellular distribution of loaded cargoes. This knowledge furthers our understanding of bio-nano interactions and is important for the efficient use of cationic liposomes. 相似文献
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为了解决图像检索中颜色直方图无法描述颜色空间位置信息的问题,提出了一种新的基于色彩量化的凸壳内角直方图特征.针对量化后HSV颜色空间中某一具体量化颜色值对应像素点的空间分布,首先计算包含这些像素点位置信息的凸壳,并对该凸壳的所有内角建立直方图.然后处理所有量化颜色值提取整幅图像的凸壳内角直方图特征.将该方法和一些文献中提出的方法进行的比较实验结果表明:提出的新特征可以有效地描述颜色空间位置信息,在查准率和查全率指标上均优于已有文献中的一些方法. 相似文献
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