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LB Lane 《Canadian Metallurgical Quarterly》1993,18(2):366-368
The scaphoid test described by Watson has generally been accepted as the definitive test for scaphoid instability and uses pressure against the scaphoid tubercle as the wrist moves from ulnar to radial deviation for the evaluation. This article describes a stress test done with the wrist in neutral position, which actively provokes scaphoid instability. Variations in stability can be used to grade scaphoid laxity. 相似文献
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Remote delivery of video services using mm-waves and optics 总被引:2,自引:0,他引:2
Advantages of a radio-based final drop for video delivery are outlined and spectral availability constraints that lead to the identification of the mm-wave region of the radio spectrum as the most appropriate for this application are discussed. The possibility of simultaneously supporting other broadband services, such as B-ISDN and traffic information systems (IVHS), enhance the attractiveness of a radio link. A large number of antenna units need to be served due to the limited propagation distances achievable at mm-wave frequencies, and therefore, a low-cost generation and delivery method has to be developed. In this paper, alternatives for the optical generation and distribution of mm-wave signals are reviewed and a new method is proposed that eases the bandwidth, and hence the cost, of the required optoelectronic components. An assessment of the relative merits of the methods is given 相似文献
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Presents an obituary of R. Fine, a psychologist-psychoanalyst who also excelled in chess. Fine worked for the government during World War II as a mathematician and consultant to the US Armed Forces, earned a PhD in clinical psychology in 1948, and was one of the founders of the National Psychological Association for Psychoanalysis. Fine also organized several centers for psychoanalytic training and was the founder of the American Psychological Association's Division 29, Psychotherapy. He wrote more than 100 articles and some 20 books on psychoanalysis, with an emphasis on love and work. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Bloodmeal digestion in midguts of the sandflies Phlebotomus papatasi and Phlebotomus langeroni (Diptera: Psychodidae) was investigated in optimized assays to detect general protease, trypsin and aminopeptidase activities using synthetic substrates. Optimal activity occurred at pH 8-9 for all enzymes examined in both species. Protease activity peaked at 24-34 h post human bloodmeal in midguts of P. papatasi and 34-48 h in P. langeroni; all endo- and exoprotease activities were completed by 50 h in P. papatasi compared to 72 h in P. langeroni. Hydrolysis of two chymotrypsin substrates was < 2% of trypsin activity in both species. Aminopeptidase activity was associated mainly with the midgut wall, whereas trypsin activity was confined to the midgut lumen. A feature of digestion in P. langeroni was the high level of aminopeptidase recorded within 10 h of the bloodmeal. 相似文献