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This paper reviews and discusses what is known about the relationship between identity in state, allele frequency, inbreeding coefficients, and identity by descent in various uses of these terms. Generic definitions of inbreeding coefficients are given, as ratios of differences of probabilities of identity in state. Then some of their properties are derived from an assumption in terms of differences between distributions of coalescence times of different genes. These inbreeding coefficients give an approximate measurement of how much higher the probability of recent coalescence is for some pair of genes relative to another pair. Such a measure is in general not equivalent to identity by descent; rather, it approximates a ratio of differences of probabilities of identity by descent. These results are contrasted with some other formulas relating identity, allele frequency, and inbreeding coefficients. Additional assumptions are necessary to obtain most of them, and some of these assumptions are not always correct, for example when there is localized dispersal. Therefore, definitions based on such formulas are not always well-formulated. By contrast, the generic definitions are both well-formulated and more broadly applicable.

This paper reviews and discusses what is known about the relationship between identity in state, allele frequency, inbreeding coefficients, and identity by descent in various uses of these terms. Generic definitions of inbreeding coefficients are given, as ratios of differences of probabilities of identity in state. Then some of their properties are derived from an assumption in terms of differences between distributions of coalescence times of different genes. These inbreeding coefficients give an approximate measurement of how much higher the probability of recent coalescence is for some pair of genes relative to another pair. Such a measure is in general not equivalent to identity by descent; rather, it approximates a ratio of differences of probabilities of identity by descent. These results are contrasted with some other formulas relating identity, allele frequency, and inbreeding coefficients. Additional assumptions are necessary to obtain most of them, and some of these assumptions are not always correct, for example when there is localized dispersal. Therefore, definitions based on such formulas are not always well-formulated. By contrast, the generic definitions are both well-formulated and more broadly applicable.

A linear stability analysis of a thin shear-thinning film with a deformable top surface flowing down an inclined porous substrate modelled as a smooth substrate with velocity slip at the wall is examined, and the physical mechanism for the long-wave instability is analysed. Through a phenomenological model, the influence of slip velocity and the shear-thinning rheology on the wave speed of long surface waves on a non-Newtonian shear-thinning film down a substrate with velocity slip is predicted. The viscosity disturbance plays a significant role in the destabilization of the flow system. Indeed, slip at the bottom that accounts for the characteristics of the porous/rough substrate does not affect the physical mechanism of the instability. However, it is shown that slip at the bottom enhances the inertia effects which in turn destabilizes the flow system at smaller Reynolds numbers.

Population differentiation is usually evaluated in computing various statistics from allelic frequencies in each sample and applying a statistical test to tentatively reject the null hypothesis Ho. An alternative way of testing population differentiation is presented that is based on an exact nonparametric procedure.

The Advanced Incineration-Vitrification Hybrid System (SHIVA) process is well suited to treat organic and mineral waste, with high alpha contamination management capabilities. It allows, in a single reactor, waste incineration by a plasma burner and ash vitrification in a cold wall direct glass induction melting system. The SHIVA trial demonstrates the successful processing of an inactive waste stream analogue that contains a mixture of mineral and organic ion exchange media. The waste loading attains a promising value of 38 wt.% and a glass wasteform is obtained. Further, the microstructure, chemical composition, and chemical durability of the wasteform are characterised.

Wolbachia are a group of intracellular inherited bacteria that infect a wide range of arthropods. They are associated with a number of different reproductive phenotypes in their hosts, such as cytoplasmic incompatibility, parthenogenesis and feminization. While it is known that the bacterial strains responsible for these different host phenotypes form a single clade within the α-Proteobacteria, until now it has not been possible to resolve the evolutionary relationships between differentWolbachia strains. To address this issue we have cloned and sequenced a gene encoding a surface protein ofWolbachia (wsp) from a representative sample of 28Wolbachia strains. The sequences from this gene were highly variable and could be used to resolve the phylogenetic relationships of differentWolbachia strains. Based on the sequence of thewsp gene from differentWolbachia isolates we propose that theWolbachia pipientis clade be initially divided into 12 groups. As more sequence information becomes available we expect the number of such groups to increase. In addition, we present a method ofWolbachia classification based on the use of group-specificwsp PCR primers which will allowWolbachia isolates to be typed without the need to clone and sequence individualWolbachia genes. This system should facilitate future studies investigating the distribution and biology ofWolbachia strains from large samples of different host species.

We justify rigorously the convergence of the amplitude of solutions of nonlinear Schrodinger-type equations with nonzero limit at infinity to an asymptotic regime governed by the Korteweg-de Vries (KdV) equation in dimension 1 and the Kadomtsev-Petviashvili I (KP-I) equation in dimensions 2 and greater. We get two types of results. In the one-dimensional case, we prove directly by energy bounds that there is no vortex formation for the global solution of the nonlinear Schrodinger equation in the energy space and deduce from this the convergence toward the unique solution in the energy space of the KdV equation. In arbitrary dimensions, we use a hydrodynamic reformulation of the nonlinear Schrodinger equation and recast the problem as a singular limit for a hyperbolic system. We thus prove that smooth Hs solutions exist on a time interval independent of the small parameter. We then pass to the limit by a compactness argument and obtain the KdV/KP-I equation. [PUBLICATION ABSTRACT]

The population genetic structure of Plasmodium falciparum, the agent of malignant malaria, has been shown to be predominantly \"clonal\" (i.e., highly inbred) in regions of low infectivity; in high-infectivity regions, it is often thought to be panmictic, or nearly so, although there is little supporting evidence for this. The matter can be settled by investigating the parasite's genetic makeup in the midgut oocysts of the mosquito vector, where the products of meiosis can directly be observed. The developmental stages of P. falciparum are haploid, except in the oocysts of infected mosquito vectors, where two gametes fuse, diploidy occurs, and meiosis ensues. We have investigated genetic polymorphisms at seven microsatellite loci located on five chromosomes by assaying 613 oocysts in 145 mosquitoes sampled from 11 localities of Kenya, where malignant malaria is perennial and intense. There is considerable allelic variation, 16.3 ± 2.1 alleles per locus, and considerable inbreeding, ≈50% on the average. The inbreeding is caused by selfing (≈25%) and nonrandom genotype distribution of oocysts among mosquito guts (35%). The observed frequency of heterozygotes is 0.43 ± 0.03; the expected frequency, assuming random mating, is 0.80 ± 0.05. Linkage disequilibrium is statistically significant for all 21 pairwise comparisons between loci, even though 19 comparisons are between loci in different chromosomes, which is consistent with strong deviation from panmixia and the consequent reproduction of genomes as clones, without recombination between gene loci. This is of considerable evolutionary significance and of epidemiological consequence, concerning the spread of multilocus drug and vaccine resistance.

One of the most enduring ideas in spatial population genetics is that the neighbourhood size determines the extent and geographic pattern of genetic differentiation. In particular, there is a widespread belief that the effects of dispersal on genetic structure are essentially determined by a straightforward parameter: the mean-squared parent offspring distance s2, from which the neighbourhood size can be calculated as Nb 4pDs2 (for two-dimensional habitats), where D is the population density.

We consider an initial boundary value problem for a symmetrizable mixed hyperbolic-parabolic system of conservation laws with a small viscosity ε\\varepsilon, utε+F(uε)x=ε(B(uε)uxε)x.u^\\varepsilon _t+F(u^\\varepsilon )_x =\\varepsilon (B(u^\\varepsilon ) u^\\varepsilon _x )_x . When the boundary is noncharacteristic for both the viscous and the inviscid system, and the boundary condition dissipative, we show that uεu^\\varepsilon converges to a solution of the inviscid system before the formation of shocks if the amplitude of the boundary layer is sufficiently small. This generalizes previous results obtained for BB invertible and the linear study of Serre and Zumbrun obtained for a pure Dirichlet’s boundary condition.