Committee on science and the arts     

John Frazer 《Journal of The Franklin Institute》1948,246(1):78-80

In contradiction to results previously reported, it has been found that DNA prepared by a method which utilizes strong NaOH is acted on by the specific nuclease, although at a rate only 20 per cent. of that of DNA prepared by a milder method. The nature of the changes responsible for the low rate of hydrolysis of the alkali-treated DNA are not known.  相似文献   

Race and Manners for Southern Girls and Boys: “The Miss Minerva” Books and Race Relations in a Southern Children's Series     

John Scott Wilson 《Journal of American culture (Malden, Mass. : 2003)》1994,17(3):69-74

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New products     

John Quiggin 《TechTrends》2000,44(6):46-46

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A Waste of Time? (Private Rates of Return to Higher Education in the 1990s)     

John Ashworth 《Higher Education Quarterly》1997,51(2):164-188

Since 1990, there has been considerable debate concerning the benefits of the expansion of higher education and the appropriate way to fund such an expansion. This paper demonstrates that three factors are decisive to the individual contemplating higher education: national economic growth; the relative earnings of graduates and non-graduates; the difference between the average and the marginal student. The results, of analysis based on rates of return, reaffirm the view that a proportion of the costs involved in higher education can be transferred to the graduates themselves in the form of loans. However, there appear to be limits to the costs that can be transferred if all students are to judge that undergraduate study is a worthwhile proposition. Notwithstanding this, most students could be lent more income to study than is now the case and indeed an average student would be advised to take any loans despite the greater debt. Marginal students, however, are making a risky private investment and, therefore, any decisions to further expand may result in students not taking up the places.  相似文献   

Standardizing �headers’: OASIS     

Dr John Jarvis 《Learned Publishing》1995,8(3):141-143

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Essay review     

Greg Dening  John Forge  James Robert Brown 《Metascience》1996,5(2):21-39

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Knowledge bases in medicine: a review     

C A Perry 《Bulletin of the Medical Library Association》1990,78(3):271-282

Efforts to represent knowledge effectively have been central to progress in various aspects of medical informatics. These efforts range from relatively simple "electronic textbooks" to fairly sophisticated knowledge-based systems, which function as well as, or even better than, human experts faced with similar problems. Knowledge bases have been developed in many fields, but the relatively limited domains and structured language of medicine, as well as the importance of information in the provision of good medical care, have made research in medical knowledge representation an area of intense activity. This paper reviews representative knowledge bases and knowledge-based systems in medicine: electronic textbooks such as PDQ and the Hepatitis Knowledge Base (HKB), rule-based systems such as MYCIN, causal models (e.g., CASNET), and hypothesis- or frame-based systems, exemplified by PIP and INTERNIST-1. The paper describes the relationships among divergent approaches and provides a sense of current and future trends. It examines problems in knowledge-based systems, particularly in knowledge representation and acquisition, and the responses to these challenges. The latter include the use of domain-independent software shells for constructing knowledge bases, the adaptation and use of previously existing knowledge bases, and multiple uses of the same knowledge base for different purposes.  相似文献   

Into the Future:The Challenge and Promise of Technology for Digital Libraries   总被引：6，自引：1，他引：5  

John Wilkin 《中国图书馆学报》2008,34(4)

我们长期将数字图书馆作为一个独立的世界来构建,这个独立的世界中包括数字对象的创建、管理、发现、传递以及利用等。这种相对封闭的模式与高度发达的开放网络世界背道而驰。在网络世界中,用户可以通过大型的检索系统,如Google和Amazon来发现信息,还可以在管理这些信息资源的系统之外对其进行利用。当用户都涌向网络世界时,数字图书馆就面临着打破其固有封闭状态的挑战,以便适应开放的网络世界,否则将失去其实用性。当前,许多条件都给数字图书馆提供了改变现状、提高实用性的机遇。本文将讨论数字图书馆现存的典型模式以及该模式带来的后果,讨论数字图书馆工作改革的方式,并简要探讨数字图书馆建设中的成功技术实例。  相似文献   

An Analysis of Academic Library Web Pages for Faculty     

Susan J. Gardner  John Eric Juricek  F. Grace Xu 《The Journal of Academic Librarianship》2008,34(1):16-24

Web sites are increasingly used by academic libraries to promote key services and collections to teaching faculty. This study analyzes the content, location, language, and technological features of fifty-four academic library Web pages designed especially for faculty to expose patterns in the development of these pages.  相似文献   

The condition is critical: continuing professional development of library and information services staff     

John van Loo  MARGARET REDFERN 《Health information and libraries journal》1995,12(1):13-21