Single-species population models often include density-dependence phenomenologically in order to approximate higher order mechanisms. Here we consider the common scenario in which density-dependence acts via depletion of a renewed resource. When the response of the resource is very quick relative to that of the consumer, the consumer dynamics can be captured by a single-species, density-depende...

We present some properties of k-existentially-closed and k-saturated graphs, as steps toward discovering a 4-saturated graph. We demonstrate a construction for 2-saturated graphs, prove the existence of k-e.c. graphs, and show that the chromatic number of k-saturated graphs increases with k. Finally, we detail an algorithm for finding k-existentially-closed and k-saturated graphs.

Local species diversity is maintained over ecological time by a balance between dispersal and species interactions. Local-regional species richness relationships are often used to investigate the relative importance of these two processes and the scales at which they operate. For communities undergoing succession, theory predicts a temporal progression in local-regional species richness relatio...

The objective of present paper is to examine the peristaltic flow of magnetohydrodynamic (MHD) Jeffrey fluid saturating porous space in a channel through rotating frame. Unlike the previous attempts, the flow formulation is based upon modified Darcy's law porous medium effect in Jeffrey fluid situation. In addition the impacts due to Soret and Dufour effects in the radiative peristaltic flow ar...

We study numerically the effects of finite curvature and ellipticity of the Gaussian beam on propagation through a saturating nonlinear medium. We demonstrate generation of different types of pattern arising from the input phase structure as well as the phase structure imparted by the nonlinear medium.

A degree is saturated bounding if it can compute a saturated model for any complete, decidable theory whose types are all computable. All high and PA degrees are saturated bounding (following from results of Jockusch and MacIntyre-Marker.) We show that for every n, no lown c.e. degree is saturated bounding, extending the previous known result that 0 is not saturated bounding, by Millar.

Visually responsive neurons typically exhibit a monotonic-saturating increase of firing with luminance contrast of the stimulus and are able to adapt to the current spatiotemporal context by shifting their selectivity, therefore being perfectly suited for optimal contrast encoding and discrimination. Here we report the first evidence of the existence of neurons showing selective tuning for cont...

The present work is the successful extension of an improved equation of state (EOS) to refrigerant fluids. The objective is the prediction of isothermal and saturated liquid densities of refrigerants. Two temperature-independent parameters appearing in the modified EOS are closely related to critical point properties of refrigerant fluids. Our results showed that, the proposed EOS can predict w...