The gypsy moth, Lymantria dispar, is a major defoliator of deciduous trees throughout the northern hemisphere. Introduced into eastern Massachusetts from Europe in 1868 or 1869, it has gradually spread south and west and will soon occupy most of the hardwood forests in the eastern United States and Canada. The gypsy moth has been the subject of intensive study by scientists throughout the world...

A bioeconomic simulation model of the two interacting fish species cod (Gadus morhua) and capelin (Mallotus villosus) and their fisheries is presented and applied to assess the consequences of changes in the population dynamics of these important fish stocks in the Barents Sea. In each scenario, the population dynamics of the fish species are changed by an external reduction of the reproductive...

different discrete models of population dynamics of certain insects have been investigated under various feasible conditions within the framework of nonlinear dynamics. evolutionary phenomena are discussed through bifurcation analysis leading to chaos. some tools of nonlinear dynamics, such as lyapunov characteristic exponents (lce), lyapunov numbers, correlation dimension, etc. are calculated ...

conclusions carriage of pvl-positive s. aureus is common in this region, even in the low frequency of mrsa colonization. the detection of acme-arca gene in s. aureus isolates is a public-health concern and demands continued surveillance and close monitoring. results among the 813 subjects screened, 83 (10.2%) were persistent carriers, 86 (10.6%) were transient carriers and 644 (79.2%) cases wer...

In this paper we use a class of stochastic functional Kolmogorov-type model with jumps to describe the evolutions of population dynamics. By constructing a special Lyapunov function, we show that the stochastic functional differential equation associated with our model admits a unique global solution in the positive orthant, and, by the exponential martingale inequality with jumps, we dis...

Title:Increased risk for chronic comorbid disorders in patients with inflammatory arthritis: a population based study Authors: Jennie Ursum ([email protected]) Mark MJ Nielen ([email protected]) Jos WR Twisk ([email protected]) Mike JL Peters ([email protected]) François G Schellevis ([email protected]) Micheal T Nurmohamed ([email protected]) Joke C Korevaar ([email protected])

The severity of influenza epidemics, which can potentially become a pandemic, has been very difficult to predict. However, past efforts were focusing on gene-by-gene approaches, while it is acknowledged that the whole genome dynamics contribute to the severity of an epidemic. Here, putting this rationale into action, I describe a simple measure of the amount of reassortment that affects influen...

Detailed observation of the movement of individual animals offers the potential to understand spatial population processes as the ultimate consequence of individual behaviour, physiological constraints and fine-scale environmental influences. However, movement data from individuals are intrinsically stochastic and often subject to severe observation error. Linking such complex data to dynamical...

It is one thing to show that herbivorous insects affect plant performance. It is an entirely different matter to demonstrate that insect herbivory affects plant population dynamics. There is a vast literature on insect pests of crop plants that shows how attack by defoliating, sucking, stem-mining, and gall-forming species can delay seed ripening, reduce seed production and individual seed weig...