Grofit: Fitting biological growth curves

Nitrogen Transformation, Ammonia Volatilization Loss, and Nitrate Leaching in Organically Enhanced Nitrogen Fertilizers Relative to Urea

“…Nitrification from the organic enhanced fertilizers and from urea was modeled using the Gompertz growth model (Kahm et al, 2010), which has the following general form:…”

The sigmoidal growth of operating system security vulnerabilities: An empirical revisit

“…4 The AIC values and F-tests provide a decent comparative toolbox for the initial analysis. The comparable AIC comparison algorithm of Kahm et al (2010) has been also used to approach much more complex biological datasets with thousands of curves to be fitted (Vaas et al, 2012). The small analytical toolbox is still needed also for the present empirical experiment that fits 3 29 2 3 40 294 × × ( )+ × ( )= growth curves; three for each of the 29 products in the primary twofold Red Hat dataset, augmented with the evaluation of the three growth curves for the forty examined Microsoft operating system products.…”

“…First, the iterative algorithm of Kahm et al (2010) obtains the starting values from smooth spline fits, and then uses these to fit analytical growth curves, using Akaike's information criterion to select the best fit. Second, R contains also a number of so-called self-starting values for common functions, including the logistic and the Gompertz function (Fox and Weisberg, 2010).…”

Measurement of cell-substrate impedance and characterization of cancer cell growth kinetics with mathematical model

“…40,41 The pattern of growth curves follows a sigmoidal curve including lag phase, exponential growth and maximum cell growth of stationary phase. 17,42 In this study, the modified Gompertz equation was derived and used to observe cell growth kinetics on collagen coated electrode surface. The biological parameters such as A (asymptote at maximal cell density), µ m (maximum growth rate), and λ (lag period) were substitute in the formula to derive a modified Gompertz equation to describe the cell growth behavior as mathematical expression as following.…”

“…Because the growth rate represented by the slope of exponential curve (µ max ) which determined from linear region of a curve known to exhibit the characteristic property of each different cells at a given culture time point. 17 In this study, cell-based impedance measurement system was fabricated and the surface of electrodes was coated with collagen protein to facilitate the SCC7 and HeLa cell attachment. The AC frequency responsive impedance value from cancer cells was measured and showed different growth rate as of surface modification.…”