This paper presents a genetic algorithmic approach to the shortest path (SP) routing problem. Variable-length chromosomes (strings) and their genes (parameters) have been used for encoding the problem. The crossover operation exchanges partial chromosomes (partial routes) at positionally independent crossing sites and the mutation operation maintains the genetic diversity of the population. The...

BACKGROUND Glomerular filtration rate (GFR)-estimating equations are used to determine the prevalence of chronic kidney disease (CKD) in population-based studies. However, it has been suggested that since the commonly used GFR equations were originally developed from samples of patients with CKD, they underestimate GFR in healthy populations. Few studies have made side-by-side comparisons of th...

A matrix model based on a discrete time form of the logistic equation and the Leslie matrix model was developed for density-dependent population growth; the model is simpler and more easily applied than the model developed by Liu and Cohen in 1987 using a different discrete time form of the logistic equation. The new model requires no additional parameters, matrices, or mathematical functions, ...

This paper is devoted to the study of an eigenvalue second order differential equation, supplied with homogenous Dirichlet conditions and set on the real line. In the linear case, the equation arises in the study of a reaction-diffusion system involved in disease propagation throughout a given population. Under some relations upon the real parameters and coefficients, we present some existence ...

Particulate processes are often encountered in industry. The polydispersity of some key properties characterizes particulate processes and makes them ill-suited to be modeled within the framework of conventional conservation equations only. In the mid 60s a tool called Population Balance Equation was developed to quantify the dynamics of particulate processes. This paper aims to give an introdu...

We extend the theory of noise-induced phase synchronization to the case of a neural master equation describing the stochastic dynamics of an ensemble of uncoupled neuronal population oscillators with intrinsic and extrinsic noise. The master equation formulation of stochastic neurodynamics represents the state of each population by the number of currently active neurons, and the state transitio...

BACKGROUND The purpose of this study was to compare three different equations to calculate estimated glomerular filtration rate (eGFR) based on serum creatinine (SCr) and to estimate the prevalence of chronic kidney disease (CKD) in the Icelandic population. METHODS This was a cross-sectional study using data from the Reykjavik Heart Study. GFR was estimated with three equations: Equation I w...

BACKGROUND Glomerular filtration rate (GFR) is essential for renal function evaluation and classification of chronic kidney disease (CKD), while the reference method in children are cumbersome. In the Chinese children, there was no data about GFR measured through plasma or renal clearance of the exogenous markers, and therefore no validated GFR-estimating tools in this population. METHODS We ...

This paper is devoted to the study of the stability of limit cycles of a nonlinear delay differential equation with a distributed delay. The equation arises from a model of population dynamics describing the evolution of a pluripotent stem cells population. We study the local asymptotic stability of the unique nontrivial equilibrium of the delay equation and we show that its stability can be lo...