Pii: S0025-5564(00)00043-2
نویسنده
چکیده
A number of pathogens may be transmitted from parent to child at or before birth (vertically) or from one individual to another by contact (horizontally). A natural deterministic and non-spatial model, introduced by Lipsitch et al. [Proc. Roy. Soc. London Ser. B 260 (1995) 321] shows that an epidemic is possible if the vertical transmission or the horizontal transmission is high enough. In contrast, we introduce a stochastic spatial model that shows that, on a particular graph, if the vertical transmission is not high enough, then the infected individuals disappear even for very high horizontal transmission. This illustrates the fact that introducing space may greatly change the qualitative behavior of a model. Ó 2000 Elsevier Science Inc. All rights reserved.
منابع مشابه
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In this paper, we establish a mathematical model of two species with stage structure and the relation of predator±prey, to obtain the necessary and sucient condition for the permanence of two species and the extinction of one species or two species. We also obtain the optimal harvesting policy and the threshold of the harvesting for sustainable development. Ó 2000 Elsevier Science Inc. All rig...
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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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