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101.
Renner R 《Environmental science & technology》1996,30(2):74A
Government. 相似文献
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Previous research using monitoring tasks suggests that syllables do not play a role in the initial processing of speech by English listeners. The role of syllables in a different task, 1 involving the speeded comparison of 2 nonwords, was investigated. In 2 experiments, responses to nonword pairs that shared a complete syllable were significantly faster than responses to pairs that shared part of a syllable when the shared unit was at the beginning or in the middle of the nonwords. Results were mixed when the shared unit was at the end of the nonwords, possibly reflecting a confounding effect of rhyme. Findings suggest that syllabified representations of the nonwords may be used in a comparison task, even in English. Results are interpreted relative to different demands of the nonword comparison and monitoring tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Nyquist RM Ataka K Heberle J 《Chembiochem : a European journal of chemical biology》2004,5(4):431-436
The catalytic action of membrane proteins is vital to many cellular processes. Yet the molecular mechanisms remain poorly understood. We describe here the technique of evanescent infrared difference spectroscopy as a tool to decipher the structural changes associated with the enzymatic action of membrane proteins. Functional changes as minute as the protonation state of individual amino acid side chains can be observed and linked to interactions with a ligand, agonist, effector, or redox partner. 相似文献
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This paper presents costs per US motor vehicle crash victim differentiated into many more diagnostic categories than prior estimates. These unit costs, which include the first keyed to the 1990 edition of Abbreviated Injury Scale (AIS) threat-to-life severity scores, are reported by body part, whether a fracture/dislocation was involved, and the maximum AIS score among the victim's injuries. This level of detail allows for a more accurate estimation of the social costs of motor vehicle crashes. It also allows for reliable analyses of interventions targeting narrow ranges of injuries. The paper updates the medical care data underlying the US crash costs from 1979 to 1986 to the mid 1990s and improves on prior productivity cost estimates. In addition to presenting the latest generation of crash victim costs, this paper analyzes the effects of applying injury costs classified by AIS code from the 1985 edition to injury incidence data coded with the 1990 edition of AIS. This long-standing practice results in inaccurate cost-benefit analyses that typically overestimate benefits. This problem is more acute when old published costs adjusted for inflation are used rather than the recent costs. 相似文献
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The application of hollow and filament-filled single asymmetric membrane fibers, consisting of a thin silicone layer on a tubular microporous support, for removing CO(2) in suppressed ion chromatography effluents is described. With appropriate choice of the removal device and operating conditions, the CO(2) can be essentially quantitatively (99+%) removed. For carbonate-based eluents, the use of such devices greatly reduces or eliminates the water dip, permitting better quantitation of poorly retained anions that elute close to the dip, allows practical gradient chromatography, and improves noise levels and attainable detection limits. In hydroxide eluent chromatography, the device largely removes the response from CO(2) present in the samples; this greatly aids atmospheric trace gas analysis by IC. Device dimensions are such that the dispersion introduced by the device is small. 相似文献
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Security in the wild: user strategies for managing security as an everyday,practical problem 总被引:1,自引:0,他引:1
Paul?DourishEmail author Rebecca?E.?Grinter Jessica?Delgado de la Flor Melissa?Joseph 《Personal and Ubiquitous Computing》2004,8(6):391-401
Ubiquitous and mobile technologies create new challenges for system security. Effective security solutions depend not only on the mathematical and technical properties of those solutions, but also on people’s ability to understand them and use them as part of their work. As a step towards solving this problem, we have been examining how people experience security as a facet of their daily life, and how they routinely answer the question, “is this system secure enough for what I want to do?” We present a number of findings concerning the scope of security, attitudes towards security, and the social and organizational contexts within which security concerns arise, and point towards emerging technical solutions. 相似文献