We derive formulas for mean deep coalescence cost, for either a fixed species tree or a fixed gene tree, under probability distributions that satisfy the exchangeability property. We then apply the formulas to study mean deep coalescence cost under two commonly used exchangeable models—the uniform and Yule models. We find that mean deep coalescence cost, for either a fixed species tree or a fix...

By using microfluidic chips, we investigate the stability regarding coalescence of droplet pairs under an electric field as a function of drop separation and ac field intensity. Three different regimes are found: stable, coalescence, and partial merging. From this, we identify the two breaking scenarios of a one dimensional train of droplets: in one case the coalescence front propagates; in the...

The processes of char fragmentation, including mineral partitioning and particulate matter (PM) formation during dense porous combustion, were observed by a site percolation model. This model simulated the diffusion-controlled regime size distributions included minerals in typical bituminous coal determined computer-controlled scanning electron microscope (CCSEM), data put into matrix randomly....

The major importance of drop coalescence in a number of natural and industrial processes provides the motivation for fundamental experimental and theoretical studies on its mechanics. One of the main difficulties of such investigations is related with the presence of a thin liquid film, typically of order 10−4 of the drop size. In numerical studies of coalescence this requires very fine spatial...

The climatic fluctuations of the Quaternary have influenced the distribution of numerous plant and animal species. Several species suffer population reduction and fragmentation, becoming restricted to refugia during glacial periods and expanding again during interglacials. The reduction in population size may reduce the effective population size, mean coalescence time and genetic variation, whe...

The paper is concerned with methods for the estimation of the coalescence time (time since the most recent common ancestor) of a sample of intraspecies DNA sequences. The methods take advantage of prior knowledge of population demography, in addition to the molecular data. While some theoretical results are presented, a central focus is on computational methods. These methods are easy to implem...

We propose a method of estimating the time to the most recent common ancestor (TMRCA) of a sample of DNA sequences, whose variation is characterized by single nucleotide polymorphisms (SNPs). Neither the proposed point estimate nor its confidence interval depends on the demographic history of the population, such as population size, growth, or migration pattern. Simulations show that the estima...

We have measured the short-time and long-time elastic responses to compression of various types of surfactant layers adsorbed at oil-water interfaces. We prepared reasonably monodisperse oil-in-water emulsions with the same surfactants and monitored the time evolution of the emulsion droplets' diameter. We used a broad variety of surfactants (cationic, nonionic, and small polymers) and alkanes ...

A new general type of morphogenetic process has been revealed by experiments on the phenomenon of non-coalescence between different strain types {alpha and delta) in the sponge Ephydatia fluviatilis. The question investigated was whether any process of cell adhesion was responsible for the phenomenon. Preliminary results suggested that the cells might show specific adhesion but further results ...

This paper aims to reveal the mechanical properties, energy evolution characteristics, and dynamic rupture process of preflawed granite under impact loading with different rock bridge angles strain rates. A series experiments were conducted along separate Hopkinson press bar (SHPB) testing system analyze study overall fracture process. Under load, peak stress increases increase angle rate, but ...