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971.
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy.  相似文献   
972.
973.
The being together intervention intends to raise teacher capacity in Norwegian Early Childhood Education and Care (ECEC) institutions and promote social and emotional development in preschoolers by implementing an authoritative (warm and predictable) adult style in the institution. An authoritative adult balances between building up high quality interactions with children, while at the same time having a predictable structure with clear norms and social expectations in the learning environment. The purpose of this study was to investigate what helped the ECEC institutions to successfully implement the program principles and core components, and what were the challenges. The staff groups of seven Norwegian ECEC institutions in different municipalities who took part in the innovation were interviewed at the beginning and before the end of the first year of implementation. Data analysis identified five success criteria in the implementation process; strong commitment to the authoritative adult style, strong focus on the implementation process, advanced support systems, highly involved leaders, and a collective orientation. These elements resulted in a shared vision and an academically grounded practice in the ECEC institutions. Staff members without formal professional training and a lack of written documentation in the ECEC institutions should be given more consideration in further improvement of the capacity building.  相似文献   
974.
975.
In China, educational publishing is devoted to publishing mainly textbooks and teaching materials. For a long time, education publishing has dominated others in China’s publishing industry. However, after entering the new century, especially in the last 2 years, there has been the impact of changes in the College-Entrance Examination, the Invitation to Bid for Compilation and Publication of Textbooks, government procurement and Scientific and Technological Advancement for supplementary books. Therefore, publishing for education has been losing its previous major role and dominance. For making a leap forward and breakthrough in educational publication, we must open up a new train of thought for the development of educational publishing, we need three distinct transformations: first, change in publishing mode from extensive to intensive growth. Second, transformation from variety-scale to market-scale expansion. Third, transformation from being just a provider of content to one providing both content and services.  相似文献   
976.
This paper attempts a direct comparison of the available alternative channels that can be employed in a cross media publishing scheme. More precisely it examines the content, the publishing speed, and the rhythm of the publishing channels. Interesting conclusions are drawn concerning the characteristics of each channel. A new publishing channel is proposed in order to allow newspapers to directly compete with radio and TV channels.  相似文献   
977.
978.
Negation recognition in medical narrative reports   总被引:1,自引:0,他引:1  
Substantial medical data, such as discharge summaries and operative reports are stored in electronic textual form. Databases containing free-text clinical narratives reports often need to be retrieved to find relevant information for clinical and research purposes. The context of negation, a negative finding, is of special importance, since many of the most frequently described findings are such. When searching free-text narratives for patients with a certain medical condition, if negation is not taken into account, many of the documents retrieved will be irrelevant. Hence, negation is a major source of poor precision in medical information retrieval systems. Previous research has shown that negated findings may be difficult to identify if the words implying negations (negation signals) are more than a few words away from them. We present a new pattern learning method for automatic identification of negative context in clinical narratives reports. We compare the new algorithm to previous methods proposed for the same task, and show its advantages: accuracy improvement compared to other machine learning methods, and much faster than manual knowledge engineering techniques with matching accuracy. The new algorithm can be applied also to further context identification and information extraction tasks.
Lior RokachEmail:
  相似文献   
979.
Document length is widely recognized as an important factor for adjusting retrieval systems. Many models tend to favor the retrieval of either short or long documents and, thus, a length-based correction needs to be applied for avoiding any length bias. In Language Modeling for Information Retrieval, smoothing methods are applied to move probability mass from document terms to unseen words, which is often dependant upon document length. In this article, we perform an in-depth study of this behavior, characterized by the document length retrieval trends, of three popular smoothing methods across a number of factors, and its impact on the length of documents retrieved and retrieval performance. First, we theoretically analyze the Jelinek–Mercer, Dirichlet prior and two-stage smoothing strategies and, then, conduct an empirical analysis. In our analysis we show how Dirichlet prior smoothing caters for document length more appropriately than Jelinek–Mercer smoothing which leads to its superior retrieval performance. In a follow up analysis, we posit that length-based priors can be used to offset any bias in the length retrieval trends stemming from the retrieval formula derived by the smoothing technique. We show that the performance of Jelinek–Mercer smoothing can be significantly improved by using such a prior, which provides a natural and simple alternative to decouple the query and document modeling roles of smoothing. With the analysis of retrieval behavior conducted in this article, it is possible to understand why the Dirichlet Prior smoothing performs better than the Jelinek–Mercer, and why the performance of the Jelinek–Mercer method is improved by including a length-based prior.
Leif AzzopardiEmail:
  相似文献   
980.
Search engine discoverability programs have changed the fundamentals of book marketing by enabling content inside the book to be used as the source of marketing itself via search results inside books. The internet trifecta of search, browse, buy is the end game but the complexities of making this work is explored along with an in-depth overview of the potential upside and difficulties of online content purchase models.  相似文献   
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