In this paper we consider epidemic models of directly transmissible SIR (susceptible → infective → recovered) and SEIR (with an additional latent class) infections in fully-susceptible populations with a social structure, consisting either of households or of households and workplaces. We review most reproduction numbers defined in the literature for these models, including the basic reproducti...

OBJECTIVE To estimate the basic reproduction number (R0) of dengue fever including both imported and autochthonous cases. METHODS The study was conducted based on epidemiological data of the 2003 dengue epidemic in Brasília, Brazil. The basic reproduction number is estimated from the epidemic curve, fitting linearly the increase of initial cases. Aiming at simulating an epidemic with both aut...

Transmission of encephalomyocarditis-virus (EMCV) has been estimated in experiments, but never using field data. In this field study, a farm in Belgium was selected where the presence of EMCV was confirmed by necropsy and virus isolation. Serology was used to estimate the transmission parameter R0. In one compartment with 630 pigs, 6 pens were fully sampled, in the remaining 38 pens, 2 randomly...

The boundary value problem z ′′ ρ·g·z − p /γ 1 z′ 2 3/2 − 1/r · 1 z′ 2 ·z′, r ∈ r1, r0 , z′ r1 − tan π/2 − αg , z′ r0 − tanαc, z r0 0, and z r is strictly decreasing on r1, r0 , is considered. Here, 0 < r1 < r0, ρ, g, γ, p, αc, αg are constants having the following properties: ρ, g, γ are strictly positive and 0 < π/2 − αg < αc < π/2. Necessary or sufficient conditions are given in terms of p f...

The dynamics of a general in-host model with intracellular delay is studied. The model can describe in vivo infections of HIV-I, HCV, and HBV. It can also be considered as a model for HTLV-I infection. We derive the basic reproduction number R0 for the viral infection, and establish that the global dynamics are completely determined by the values of R0. If R0 < or = 1, the infection-free equili...

We examine, with asymptotic analysis and numerical simulation, the iterated stretching dynamics of FENE and Oldroyd-B jets of initial radius r0 , shear viscosity n, Weissenberg number We, retardation number S, and capillary number Ca. The usual Rayleigh instability stretches the local uniaxial extensional flow region near a minimum in jet radius into a primary filament of radius @Ca(12S)/We#r0 ...

BACKGROUND Within the last few decades Culicoides spp. (Diptera: Ceratopogonidae) emerged Europe-wide as a major vector for epizootic viral diseases e.g. caused by Bluetongue (BT) or Schmallenberg virus. In accordance with the EU regulation 1266/2007, veterinary authorities are requested to determine vector-free periods for loosing trade and movement restrictions of susceptible livestock. Addit...

Matsucoccus matsumurae (Kuwana) (Hemiptera: Coccoidea: Matsucoccidae) is an invasive alien species and a destructive pest of two native Chinese pines, Pinus tabulaeformis Carr. and P. massoniana Lamb., throughout the eastern regions of China. The pathogenicity of three entomopathogenic fungi, Lecanicillium lecanii strain V3.4504 and V3.4505, Fusarium incarnatum-equiseti strain HEB01 and Lecanic...