2014 We have employed fourth-order coherence-function theory to study the influence of the partialcoherence properties of pump beams on the laser-induced gratings. First, we examine the formation of molecular reorientational grating. The different roles of phase fluctuation and amplitude fluctuation have been pointed out. A time-delayed method has been proposed to distinguish molecular reorient...

Theoretical work has shown that reduced phenotypic heterogeneity leads to population instability and can increase extinction potential, yet few examples exist of natural populations that illustrate how varying levels expressed diversity may influence population persistence, particularly during periods of stochastic environmental fluctuation. In this study, we assess levels of expressed variatio...

We extend the one-locus two allele Moran model of fixation in a haploid population to the case where the total size of the population is not fixed. The model is defined as a two-dimensional birth-and-death process for allele number. Changes in allele number occur through density-independent death events and birth events whose per capita rate decreases linearly with the total population density....

Seasonal environmental changes have the potential to influence the genetic structure of species with a short generation time, such as Drosophila. We previously found the seasonal change in linkage disequilibrium (LD) between the chemoreceptor (Cr) genes in a local Japanese population (Kyoto [KY]). This could be caused by fluctuation in the population size or selection in temporally heterogeneou...

The effective population size is required to predict the rate of inbreeding and loss of genetic variation in wildlife. Since only census population size is normally available, it is critical to know the ratio of effective to actual population size (NJN). Published estimates of NJN (192 from 102 species) were analysed to identify major variables affecting the ratio, and to obtain a comprehensive...

A delayed three-species periodic food-chain system with Holling type-II functional response is investigated. By using Gaines and Mawhin's continuation theorem of coincidence degree theory, a set of easily verifiable sufficient conditions is derived for the existence of positive periodic solutions to the system. 1. Introduction. A rather characteristic behavior of population dynamics is the ofte...

Networks of excitatory and inhibitory neurons display asynchronous irregular (AI) states, where the activities of the two populations are balanced. At the single cell level, it was shown that neurons subject to balanced and noisy synaptic inputs can display enhanced responsiveness. We show here that this enhanced responsiveness is also present at the network level, but only when single neurons ...

This note proves an upper bound for the fluctuations of a second-class particle in the totally asymmetric simple exclusion process. The proof needs a lower tail estimate for the last-passage growth model associated with the exclusion process. A stronger estimate has been proved for the corresponding discrete time model, but not for the continuous time model we work with. So we take the needed e...

The increasing complexity of the conventional grid due to population growth, advancement in technology, and infrastructures are the factors that contribute immensely to instability, insecurity, and inefficiency of the use of electrical energy. To overcome the problems, the environmental energy sustainability calls for the use of renewable energy for sustainability of power supply. Intermittency...

Despite the utility of gastropod models for the study of evolutionary processes of great generality and importance, their effective population size has rarely been estimated in the field. Here, we report allele frequency variance at three allozyme-encoding loci monitored over 7 years in a population of the invasive freshwater pulmonate snail Physa acuta (Draparnaud 1805), estimating effective p...