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Terrorism: A Reference Handbook, Stephen Atkins, Santa Barbara, ABC-CLIO (1992), 199 pp. Terrorism: Roots, Impact, Responses, Lawrence Howard (Ed.), Prager, New York (1992), 193 pp. Hostage-Taking Terrorism: Incident Response Strategy, Alastair MacWillson, St Martins, New York (1992), 263 pp. 相似文献
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Despite the existence of an impressive body of work on human immune responses against filarial infections, the occurrence of a protective response to infection remains unclear. Here, we use a combined modelling and comparative data analysis framework to address this issue for human infections with the filarial parasite, Wuchereria bancrofti. By analogy with previous work, the analysis involves the comparison of observed field patterns of infection with epidemiological patterns predicted by a mathematical model of parasite immunity. Unlike most other human helminths, which are transmitted by ingestion or dermal penetration, exposure to infection with lymphatic filariasis can be measured explicitly in terms of vector mosquito biting rates, thereby also allowing, probably for the first time, examination of the suggested role of exposure in generating herd immunity to macroparasites. Observed field patterns in this study were derived from 19 different published studies, which gave parallel estimates of community exposure rates and the corresponding age--prevalence patterns of infection, while predictions of the epidemiological impact of herd immunity were obtained using a catalytic model framework. The results provide the first conclusive evidence to date that variations in the observed age--prevalence patterns of infection in filariasis can be effectively explained by the occurrence of an exposure-driven acquisition of herd immunity. We discuss this result in terms of implications for the new World Health Organization-led initiative for the global control of this parasitic disease. 相似文献
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The reduction of nitric oxide with ammonia on an unsupported iron oxide catalyst has been studied in a continuous-flow recycle reactor using simulated flue gas. The responses of the employed reactor system to step and pulse inputs of tracer indicate that the system could be regarded as a continuous stirred tank reactor (CSTR). Preliminary tests were carried out to determine the effect of temperature and particle size on the measured reaction rates. Additional experiments were performed in order to study the influence of oxygen and water concentration on these rates. A gas chromatographic system has been developed to analyze the gas components NO, N2O, NO2, NH3, H2O, O2, CO2 and N2. In addition, the concentrations of NO and NO2 were measured with a nondisperse infrared (NDUV/NDIR) analyzer. 相似文献
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Michael Brady 《Energy》1985,10(10):1113-1118
Current energy policies have severely eroded the earth's natural atmospheric waste-receptor capacity. Present acid rain concentrations may require a switch to an alternative energy-resource emphasis. This policy recommendation follows directly from a deductive control theory demonstration which shows that, if fossil-fuel use is continued at present rates, then there is an ever-increasing risk of a man-made environmental crisis of uncertain nature and scope. 相似文献
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Burgess Curt; Tanenhaus Michael K.; Seidenberg Mark S. 《Canadian Metallurgical Quarterly》1989,15(4):620
To eliminate potential "backward" priming effects, S. Glucksberg et al (see record 1986-29080-001) introduced a variant of the cross-modal lexical priming task in which subjects made lexical decisions to nonword targets that were modeled on a word related to either the contextually biased or unbiased sense of an ambiguous word. Lexical decisions to nonwords were longer than controls only when the nonword was related to the contextually biased sense of the ambiguous word, leading Glucksberg et al to conclude that context does constrain lexical access and that the multiple access pattern observed in previous studies was probably an artifact of backward priming. We did not find nonword interference when the nonword targets used by Glucksberg et al were preceded by semantically related ambiguous or unambiguous word primes. However, we did replicate their sentence context results when the ambiguous words were removed from the sentences. We conclude that the interference obtained by Glucksberg et al is due to postlexical judgments of the congruence of the sentence context and the target, not to context constraining lexical access. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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This article describes a circuit model for infinitesimally thin inductive strips centered in homogeneous finline. The model is valid for 0.1 ≤ W/b ≤ 1.0, 0.01 ≤ T/a, and 0.4 ≤ b/a ≤ 0.5 when frequency is in the normal operating band for the rectangular waveguide shield. The error is less than 2.5%. 相似文献