We consider a version of the contact process with sexual reproduction on a graph with two levels of interactions modeling metapopulations. The population is spatially distributed into patches and offspring are produced in each patch at a rate proportional to the number of pairs of individuals in the patch (sexual reproduction) rather than simply the number of individuals as in the basic contact...

The relative extent of cell mixing in tissues of mouse chimaeras or mosaics can be studied by comparing the distributions of the two cell populations in the tissues. However, the mean patch size is misleading because it is affected by both the extent of cell mixing and the relative contributions of the two cell populations. Previous work suggested that effects attributable to differences in tis...

In this paper we study the average distance in weighted graphs. More precisely, we consider assignments of families of non-negative weights to the edges. The aim is to maximise (minimise, respectively) the average distance in the resulting weighted graph. Two variants of the problem are considered depending on whether the collection of weights is fixed or not. The main results of this paper are...

Patchy colloids are attractive as programmable building blocks for metamaterials. Inverse patchy colloids, in which a charged surface is decorated with patches of the opposite charge, are additionally noteworthy as models for heterogeneously charged biological materials such as proteins. We study the phases and aggregation behavior of a single charged patch in an oppositely charged colloid with...

as special depositional environments which are adjacent to the seas, deltas have provided a field for human habitat establishment. geomorphic features of deltas are in constant transformation due to their dynamic features. constructing dams on rivers can intensify these changes and cause either negative or positive consequences. minab delta in hormozgan province of iran is a round or crescent-s...

As special depositional environments which are adjacent to the seas, deltas have provided a field for human habitat establishment. Geomorphic features of deltas are in constant transformation due to their dynamic features. Constructing dams on rivers can intensify these changes and cause either negative or positive consequences. Minab delta in Hormozgan Province of Iran is a round or crescent-s...

the effects of some synthetic sweeteners on the rheological and physical properties of guar gum in dilute solutions were investigated.measurements include the determination of intrinsic viscosity and the particle size, surface weighted mean [d3, 2], volume weighted mean [d4,3] and specificsurface area ofguar gum andsyntheticsweeteners mixtures. the concentration of these sweeteners were 0, 0.1,...