Pii: S0025-5564(00)00048-1
نویسنده
چکیده
We formulate and investigate the properties of a model framework to mimic the transmission dynamics of the aetiological agent of scrapie in a sheep ̄ock. We derive expressions for summary parameters that characterize transmission scenarios, notably the basic reproduction number R0 and the mean generation time Tg. The timescale of epidemic outbreaks is expressed in terms of R0 and cumulants of the generation time distribution. We discuss the relative contributions to the overall rate of transmission of horizontal and vertical routes during invasion and in endemicity. Simpli®ed models are used to obtain analytical insight into the characteristics of the endemic state. Ó 2000 Elsevier Science Inc. All rights reserved.
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متن کاملPii: S0025-5564(00)00047-x
In this paper extensions to an existing procedure for generating locally identi®able reparameterisations of unidenti®able systems are presented. These extensions further formalise the constructive nature of the methodology and lend themselves to application within symbolic manipulation packages. The extended reparameterisation procedure is described in detail and is illustrated with application...
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تاریخ انتشار 2000