A total of 86 profiles from meat and egg strains of chickens (male and female) were used in this study. Different flexible growth functions were evaluated with regard to their ability to describe the relationship between live weight and age and were compared with the Gompertz and logistic equations, which have a fixed point of inflection. Six growth functions were used: Gompertz, logistic, Lope...

The authors examined the effects of marital status and family structure on disability, institutionalization, and longevity for a nationally representative sample of elderly persons using Gompertz duration models applied to longitudinal data from 3 cohorts of the Health and Retirement Study (N= 11,481). They found that parents with only stepchildren have worse outcomes than parents with only bio...

Understanding patterns of brain development before birth is of both high clinical and scientific interest. However, despite advances in reconstruction methods, the challenging setting of in-utero imaging renders precise, point-wise measurements of the rapidly changing fetal brain morphology difficult. This paper proposes a method to deal with bad measurement quality due to image noise, motion a...

This paper has two parts. The first part surveys Euler’s work on the constant γ = 0.57721 · · · bearing his name, together with some of his related work on the gamma function, values of the zeta function, and divergent series. The second part describes various mathematical developments involving Euler’s constant, as well as another constant, the Euler–Gompertz constant. These developments inclu...

A feasibility study of lactic bacteria as potential probiotics in larval cultures of marine fish was performed by investigating the survival of five strains of lactic bacteria in sea water by readily standardised procedures at different temperatures and salinities. These conditions were chosen in such a way that their combinations define a complete first order factorial design. Depending on the...

Verhulst logistic curve either grows OR decays, depending on the growth rate parameter value. A similar situation is found in the Gompertz law about human mortality. However, growth can neither be infinite nor reach a finite steady state at an infinite asymptotic time. Moreover before some decay, some growth must have occurred. For example, some levelling-off could occur at finite time, followe...

Shelf life of minimally processed vegetables is often calculated by using the kinetic parameters of Gompertz equation as modified by Zwietering et al. [Zwietering, M.H., Jongenburger, F.M., Roumbouts, M., van't Riet, K., 1990. Modelling of the bacterial growth curve. Applied and Environmental Microbiology 56, 1875-1881.] taking 5x10(7) CFU/g as the maximum acceptable contamination value consist...

Taylor's law (TL) asserts that the variance in a species' population density is a power-law function of its mean population density: log(variance) = a + b × log(mean). TL is widely verified. We show here that empirical time series of density of the Hokkaido gray-sided vole, Myodes rufocanus, sampled 1962-1992 at 85 locations, satisfied temporal and spatial forms of TL. The slopes (b ± standard ...