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排序方式: 共有614条查询结果,搜索用时 15 毫秒
1.
D Sternberg A Peled E Shezen O Abramsky W Jiang F Bertolero D Zipori 《Canadian Metallurgical Quarterly》1996,2(1):29-38
The immunological agglutination reactions of physically absorbed F(ab')2 molecules onto anionic and cationic latex particles have been investigated by means of optical absorbance measurements. These measurements have been conducted under different conditions to determine the most influential factors. Surface F(ab')2 and BSA densities, particle concentration in the reaction medium and polyethylene glycol concentration are some of these factors. Sensitized cationic and anionic latexes differ considerably with respect to their colloidal stability and reactivity. As a general rule, the sensitized cationic latex has a relatively higher colloidal stability and hence, it provides reagents with a better optical response. Less than 0.025 microgram/ml of C-reactive protein has been detected using this particle enhanced optical immunoassay. 相似文献
2.
Patrick N. Troy 《Housing Studies》1992,7(3):216-233
This paper sets out the development of four main threads of housing policy in New South Wales from the latter part of the 19th century through the first 40 years of the 20th century. Following a discussion of the social and political circumstances and debate surrounding government policy regarding landlord/tenant relations, housing quality and supply, and owner occupancy, it concludes that policy evolution is irregular and a product of the exigencies of the political process. It also suggests that although government policy did little to improve the housing situation for the underprivileged, there was nevertheless a growing acceptance by both Labor and conservative parties of the increased need for government intervention in the housing market. 相似文献
3.
Keirnan R. LaMarche Stephen L. Conway Benjamin J. Glasser Troy Shinbrot 《Granular Matter》2007,9(3-4):219-229
A cellular automata model is used to simulate a variety of granular chute flows. The model is tested against several case
studies: flow down a chute, flow past an obstacle, chute flow in which complex, counter-rotating vortices result in streamwise
surface stripes and flow near a boundary. The model successfully reproduces experimental observations in all of these cases.
These results lead us to propose that simple, rule-based, models such as this can improve our detailed understanding of dynamics
and flow within an opaque granular bed. 相似文献
4.
This article reviews the theory of successful intelligence and attempts to construct-validate the theory of successful intelligence. It describes 4 distinct converging operations that have been used in these attempts. Two sets involve internal validation of the structure of the theory and 2 sets external validation of the theory with outside criteria. The internal validation operations involve information-processing (componential) analyses and both exploratory and confirmatory factor analyses. The external validation operations involve correlational analysis and analyses of instructional interventions based on the theory. The results are generally supportive of the theory and suggest that conventional conceptions of intelligence may be too narrow. The theory is of use in consulting because it broadens the scope of skills one looks for in seeking "intelligent" people for hiring, retention, and promotion and in assessing a person's ability to do his or her current job. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
The efficacy and cost effectiveness of vaccination against influenza among elderly persons living in the community 总被引:1,自引:0,他引:1
KL Nichol KL Margolis J Wuorenma T Von Sternberg 《Canadian Metallurgical Quarterly》1994,331(12):778-784
BACKGROUND: Despite recommendations for annual vaccination against influenza, more than half of elderly Americans do not receive this vaccine. In a serial cohort study, we assessed the efficacy and cost effectiveness of influenza vaccine administered to older persons living in the community. METHODS: Using administrative data bases, we studied men and women over 64 years of age who were enrolled in a large health maintenance organization in the Minneapolis-St. Paul area. We examined the rate of vaccination and the occurrence of influenza and its complications in each of three seasons: 1990-1991, 1991-1992, and 1992-1993. Outcomes were adjusted for age, sex, diagnoses indicating a high risk, use of medications, and previous use of health care services. RESULTS: Each cohort included more than 25,000 persons 65 years of age or older. Immunization rates ranged from 45 percent to 58 percent. Although the vaccine recipients had more coexisting illnesses at base line than those who did not receive the vaccine, during each influenza season vaccination was associated with a reduction in the rate of hospitalization for pneumonia and influenza (by 48 to 57 percent, P < or = 0.002) and for all acute and chronic respiratory conditions (by 27 to 39 percent, P < or = 0.01). Vaccination was also associated with a 37 percent reduction (P = 0.04) in the rate of hospitalization for congestive heart failure during the 1991-1992 season, when influenza A was epidemic. The costs of hospitalization for all types of illness studied were lower in the vaccinated group during 1991-1992 (range of reduction, 47 to 66 percent; P < 0.005) and for acute and chronic respiratory conditions and congestive heart failure in 1990-1991 (reductions of 37 percent and 43 percent, respectively; P < or = 0.05). Direct savings per year averaged $117 per person vaccinated (range, $21 to $235), with cumulative savings of nearly $5 million. Vaccination was also associated with reductions of 39 to 54 percent in mortality from all causes during the three influenza seasons (P < 0.001). CONCLUSIONS: For elderly citizens living in the community, vaccination against influenza is associated with reductions in the rate of hospitalization and in deaths from influenza and its complications, as compared with the rates in unvaccinated elderly persons, and vaccination produces direct dollar savings. 相似文献
6.
This article evaluatively reviews the literature on dynamic testing, a collection of testing procedures designed to quantify not only the products or even the processes of learning but also the potential to learn. The article considers a variety of approaches to dynamic testing and the strengths and weaknesses of each. Moreover, the literature on each approach is reviewed and analyzed in terms of the extent to which it fulfills the claims made for it. In all of these approaches, testing involves learning at the time of test, rather than just static testing of what has been learned before. It is concluded that dynamic testing has great potential for helping to understand people's potentials but that its potential has yet to be realized fully. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Examined the 10 most cited articles published in the Psychological Bulletin over the past 4 decades. Seven of the 10 articles were methodologically oriented. A survey of the authors revealed that highly cited articles have an important message that goes beyond momentary fads, are broad in topic and intended audience, accessible, and well written. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
We study the effects of agent movement on equilibrium selection in network based spatial coordination games with Pareto dominant and risk dominant Nash equilibria. Our primary interest is in understanding how endogenous partner selection on networks influences equilibrium selection in games with multiple equilibria. We use agent based models and best response behaviors of agents to study our questions of interest. In general, we find that allowing agents to move and choose new game play partners greatly increases the probability of attaining the Pareto dominant Nash equilibrium in coordination games. We also find that agent diversity increases the ability of agents to attain larger payoffs on average. 相似文献