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181.
P. V. Sukumaran 《Resonance》1998,3(3):8-17
The bolide impact theory for mass extinctions at the Cretaceous-tertiary (K-T) boundary was a revolutionary concept. This
theory was contested by short duration global volcanism as a possible alternative cause for the K-T extinction. Though there
is a converging evidence for an extra-terrestrial impact coinciding with the terminal Cretaceous, the causative link between
the impact and the K-T mass extinction is debatable. Thus, while the impact theory is re-emerging, available evidence is still
insufficient to rule out either of the two hypotheses.
An erratum to this article is available at . 相似文献
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183.
B V Simon 《Bulletin of the Medical Library Association》1969,57(2):160-170
The need for administrative know-how in libraries is great. Problems of administration in libraries do not differ significantly from those in other types of organizations. It behooves librarians to be aware of modern management theory, as developed and tested in the environment of business, and to adopt such useful tools as operations analysis and the systems approach to problems in the library environment. 相似文献
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R J Markert A J Parisi H V Barnes S Cohen K Goldenberg L E Mieczkowski M Dunn R M Siervogel 《Bulletin of the Medical Library Association》1989,77(2):133-138
The experiences of medical students, residents, and faculty with a computerized literature searching system were evaluated. Third-year medical students, internal medicine and family practice residents, and full-time and voluntary faculty at one medical school had the opportunity to use a full-text and bibliographic medical literature retrieval system free of charge for an eleven-month period. Subjects conducted nearly nine thousand literature searches over a period of 942 system hours. Questionnaire data showed that participants could learn to use and would use an electronic information system, felt capable of using the system, utilized the system for a variety of purposes and in a number of different ways, and viewed the system as a valuable tool in searching the medical literature. The results are discussed in the context of the educational needs of the four user-groups and medical education planning by institutions. 相似文献
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187.
Cinema Demand in Spain: A Cointegration Analysis 总被引:4,自引:3,他引:1
In this paper we explain the decline in cinema attendance in Spain since 1968. We use a cointegration analysis to estimate
an individual demand function for cinema, with annual data and in terms of average attendance per inhabitant. We find that
cinema is a luxury good and that its demand is elastic with respect to its price. We also show that television acts as a deterrent
with regard to cinema attendance.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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