As we know, the coefficients of impulsive Lasota-Wazewska model are always assumed to be continuous, say, periodic and almost periodic. In this paper we consider the case when the coefficients are piecewise almost periodic, and establish an existence and uniqueness theorem of piecewise almost periodic positive solution for this model. Mathematics Subject Classifications: 34C27, 34A37

Three cases of Newcastle disease virus (NDV) found in nature had the lentogenic motif (112)G-R-Q-G-R-L(117) in their fusion protein cleavage sites. However, both intracerebral pathogenicity and intravenous pathogenicity indexes showed that these NDV isolates were virulent. In comparison with the LaSota live virus vaccine, these viruses had significant genetic variations in the hemagglutinin-neu...

For continuous self-maps of compact metric spaces, we consider the notions generic and dense chaos introduced by Lasota Snoha, their variations for distributional chaos, under assumption shadowing. We give some equivalent properties to uniform (distributional) in terms chains prove equivalence Several examples illustrating main results are also given.

We consider globally invertible and piecewise contracting maps in higher dimensions and we perturb them with a particular kind of noise introduced by Lasota and Mackey. We got random transformations which are given by a stationary process: in this framework we develop an extreme value theory for a few classes of observables and we show how to get the (usual) limiting distributions together with...

For a family of difference equations xnþ1 1⁄4 axn þ f ðxn2kÞ; n 1⁄4 0; 1; . . .;wherea [ ð0; 1Þ; k [ {1; 2; . . .}; and f : 1⁄20;1Þ! ð0;1Þ is continuous and decreasing, we find sufficient conditions for the convergence of all solutions to the unique positive equilibrium. In particular, we improve, up to our knowledge, all previous results on the global asymptotic stability of the equilibrium in...

Several physical and astrophysical problems related to accretion onto black holes and neutron stars are shortly reviewed. I discuss the observed differences between these two types of compact objects in quiescent Soft X-ray Transients. Then I review the status of various non-standard objects suggested as an alternative to black-holes. Finally I present new results and suggestion about the natur...

newcastle disease (nd) is one of the most serious illnesses of chickens. live vaccines are widely used to prevent chicken from the disease all over the world. to access the effective and potentiate nd vaccine, a homogenous subpopulation from lasota strain was selected following cultivation of the virus on primary chicken embryofibroblast (cef) cells. pathogenicity indices and molecular characte...

We consider generalized definitions of mixing and exactness for random dynamical systems in terms Markov operator cocycles. first give six fundamental cocycles view observations the randomness environments, show that they can be reduced into two different groups. Secondly, we definition Lin's criterion naturally extended to case Finally, class asymptotically periodic cocycles, Lasota-Mackey typ...