The objective of this study was to fit growth curves using nonlinear and linear functions to describe the growth of ostriches in a Brazilian population. The data set consisted of 112 animals with BW measurements from hatching to 383 d of age. Two nonlinear growth functions (Gompertz and logistic) and a third-order polynomial function were applied. The parameters for the models were estimated us...

A classification in universality classes of broad categories of phenomenologies, belonging to physics and other disciplines, may be very useful for a cross fertilization among them and for the purpose of pattern recognition and interpretation of experimental data. We present here a simple scheme for the classification of nonlinear growth problems. The success of the scheme in predicting and cha...

Lactic acid production in a batch submerged fermentation process by five Lactobacilli: bulgaricus, casei, lactis, delbrueckii and fermentum in lactose fortified whey culture were investigated. Kinetic behavior of Lactobacilli growth rate and lactose utilization was studied based on the Moser and Gompertz kinetic models. Trendline tool in Excel software was applied for fitness assessment of the ...

This paper proposes a simple model selection test between the Gompertz and the Logistic growth models based on parameter significance testing in a comprehensive linear regression. Simulations studies are provided to show the accuracy of the method. Two real-data examples are also provided to illustrate the implementation of the proposed method in practice.

In this communication, based upon the deterministic Gompertz law of cell growth, a stochastic model in tumour growth is proposed. This model takes account of both cell ssion and mortality too. The corresponding density function of the size of the tumour cells obeys a functional Fokker-Planck equation which can be solved analytically. It is found that the density function exhibits an interesting...

This study aimed to investigate and compare nonlinear growth models (NLMs) with the predicted performance of broilers using an artificial neural network (ANN). Six hundred forty broiler chicks were sexed and randomly reared in 32 separate pens as a factorial experiment with 4 treatments and 4 replicates including 20 birds per pen in a 42-day period. Treatments consisted of 2 metabolic energy le...

The modified sigmoidal bacteria growth functions (the Gompertz, logistic, and Richards) were used to evaluate the methane production process kinetics of agricultural wastes. mesophilic anaerobic co-digestion experiments conducted with various wastes as feedstocks, including cow manure, corn straw, grape leaves, vines, wine residue, strawberry tomato leaves. results showed that manure other incr...

‎‎In this paper‎, ‎the existence and uniqueness of positive solutions for a class of nonlinear initial value problem for a finite fractional difference equation obtained by constructing the upper and lower control functions of nonlinear term without any monotone requirement‎ .‎The solutions of fractional difference equation are the size of tumor in model tumor growth described by the Gompertz f...

In this study, 2 alternative growth functions, the Lomolino and the extreme value function (EVF), are introduced and their ability to predict body, carcass, and breast weight in ducks evaluated. A comparative study was carried out of these equations with standard growth functions: Gompertz, exponential, Richards, and generalized Michaelis-Menten. Goodness of fit of the functions was evaluated u...