GLOBAL STABILITY AND BIFURCATIONS ANALYSIS OF AN EPIDEMIC MODEL WITH CONSTANT REMOVAL RATE OF THE INFECTIVE

In this thesis we consider an epidemic model with a constant removal rate of infective individuals is proposed to understand the effect of limited resources for treatment of infective on the disease spread. It is found that it is unnecessary to take such a large treatment capacity that endemic equilibria disappear to eradicate the disease. It is shown that the outcome of disease spread may depend on the position of the initial states for certain range of parameters. It is also shown that the model undergoes a sequence of bifurcations including saddle-node bifurcation, subcritical Hopf bifurcation. Keyword: Epidemic model, nonlinear incidence rate, basic reproduction number, local and global stabilit

The labyrinthine morphology of Pronycticebus gaudryi (Primates, Adapiformes)

The publication of a well preserved Eocene primate, Darwinius masillae (Cercamoniinae, Notharctidae), has revived the debate on the phylogenetic relationships of Adapiformes and extant primates (Franzen et al., PLos ONE 4(5):e5723, 2009). Recently, Lebrun et al. (J Anat 216:368–380, 2010) showed that the morphology of the bony labyrinth of strepsirrhine primates conveys a strong phylogenetic signal. The study of labyrinthine morphology may thus bring a new piece of evidence to resolve phylogenetic relationships within a group. The investigation of the labyrinthine morphology of another Cercamoniinae, Pronycticebus gaudryi, reveals no synapomorphy with the labyrinths of modern anthropoids. On the contrary, Pronycticebus is closer in labyrinthine shape to extant strepsirrhines, which supports the hypothesis that the Cercamoniinae and other Adapiformes are the sister group of toothcombed primates