Microbiology
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Growth Curve Studio
from OD600 to growth parameters, residuals and comparable batch curves.
Four-parameter Logistic/Gompertz nonlinear fitting; intervals come from local covariance approximation. OD does not automatically convert the number of cells.
Diversity & Rarefaction
calculates sample diversity and compares sequencing depth through replicate sampling.
Input non-negative integer counts; relative abundance posing as counts is not supported. Dilution is sampling without replacement, and fixed random seeds can be reproduced.
Community Ordination
observes community relationships from a distance matrix and examines specified groupings.
Bray–Curtis or Jaccard; classic PCoA, reports negative eigenvalues; optional PERMANOVA, does not automatically check for differences in within-group dispersion.
Monod Growth
Calculates the specific growth rate corresponding to a limiting substrate concentration.
single substrate empirical model, no substrate inhibition or product inhibition.
Exponential Growth
estimates specific growth rate and exponential trajectory from starting and ending numbers and interval time.
stable exponential growth stage, the input start and end values must be positive.
Colony Count
Convert CFU/mL based on coating volume and dilution ratio.
Single plate point estimation; bacterial conglomeration, viable bacterial culturability and counting range influence interpretation.
Thermal Inactivation
estimates log survival decline by temperature, D-value, and z-value.
Isothermal first-order log-linear model, excluding shoulders, tails, and heat transfer; not used for sterilization process release.
Biomass Yield
Calculate apparent yield from biomass increase and substrate consumption.
Batch apparent yield, without deduction for maintenance metabolism or by-products.
Batch Monod Model
Simultaneous substrate consumption and biomass growth simulation batch culture.
Constant yield, no death and maintained metabolism, single substrate Monod.
Chemostat Steady State
Plots the effect of dilution rate on steady-state substrate and biomass.
Ideal fully mixed flow, no death and sustained metabolism, single substrate Monod.
Microbial Generations
n=log₂(N/N₀): Calculate the number of microbial generations based on the input, and provide local sensitivity curves and data export.
is the ideal binary splitting equivalent generation number, which is negative when decreasing.
Two Point Growth Rate
μ=ln(X₂/X₁)/Δt: Calculate the two-point specific growth rate based on the input, and provide local sensitivity curves and data export.
Approximate exponential change between two points; cannot locate lag period or estimate confidence interval.
Exponential Biomass
X=X₀exp(μt): Calculate exponential biomass prediction based on input, provide local sensitivity curves and data export.
is a short-term unlimited exponential phase, and the result will be rejected if it exceeds the value range.
Logistic Biomass
X=K/[1+(K/X₀−1)e^(−rt)]: compute Logistic Biomass from inputs, with local sensitivity plots and data export.
Empirical model with given parameters, no observation fitting is performed.
Serial Dilution Factor
D=stepⁿ: Calculate the total multiple of step-by-step dilution based on the input, and provide local sensitivity curves and data export.
is diluted in equal volumes; the series must be an integer.
OD Biomass Calibration
X=a·OD+b: Calculate OD and dry weight conversion based on the input, and provide local sensitivity curves and data export.
The calibration parameters depend on the strain, instrument and optical path, and must be within the linear measurement range.
Log Reduction
LR=log₁₀(N₀/N): Calculate the log reduction of microorganisms based on the input, and provide local sensitivity curves and data export.
Positive survival number; if not detected, it should not be directly substituted with zero.
Microbial Survival Fraction
S=N/N₀: Calculate survival score based on input, provide local sensitivity curve and data export.
is a count ratio only and is not automatically interpreted as a processing effect or background correction.
Decimal Reduction Time
t=D·log₁₀(N₀/N): Calculate the D value inactivation time based on the input, and provide local sensitivity curves and data export.
One-stage inactivation model at given temperature; not intended as process validation or sterilization guarantee.
D Value Temperature Correction
D(T)=Dref·10^[(Tref−T)/z]: Calculate the D value temperature correction based on the input, and provide local sensitivity curves and data export.
Empirical linear logD–T interval; cannot be extrapolated arbitrarily across materials.
Equivalent Isothermal Lethality
F=t·10^[(T−Tref)/z]: Calculate the isothermal equivalent lethal dose based on the input, and provide local sensitivity curves and data export.
Equivalent time of uniform constant temperature, does not include heating and cooling sections or cold spot verification.
Monod Inverse Substrate
S=Ks μ/(μmax−μ): Calculate the substrate required for the target growth rate based on the input, and provide local sensitivity curves and data export.
Single limiting substrate Monod model, the target growth rate must be lower than the upper limit.
Pirt Maintenance Relation
qs=μ/Y+m: Calculate Pirt substrate consumption based on input, provide local sensitivity curve and data export.
Linear empirical decomposition of substrate requirements for growth and maintenance.
Oxygen Transfer Rate
OTR=kLa(C*−CL): Calculate oxygen transfer rate based on input, provide local sensitivity curve and data export.
fully mixed liquid phase; negative values indicate the direction of net deoxygenation.
Oxygen Uptake Rate
OUR=qO₂X: Calculate the volumetric oxygen consumption rate based on the input, and provide local sensitivity curves and data export.
specific rate is based on dry weight and consistent with actual culture conditions.
Chemostat Dilution Rate
D=F/V: Calculate the chemostat dilution rate based on the input, and provide local sensitivity curves and data export.
has equal volume of inlet and outlet fluid; dilution rate alone cannot be used to determine whether washout has occurred.
Volumetric Cell Productivity
Px=DX: Calculate cell volume productivity based on input, provide local sensitivity curves and data export.
Steady-state continuous culture without cell reflux.
Inoculum Volume Balance
Vin=Vfinal Xtarget/Xseed: Calculate the inoculation volume material balance based on the input, and provide local sensitivity curves and data export.
is uniformly mixed and has no immediate loss; it is just a mass balance and does not involve culture operating conditions.
Poisson Zero Detection
P(0)=exp(−cV): Calculate count Poisson zero detection probability based on input, provide local sensitivity curve and data export.
Poisson sampling of independent uniform distributions, not suitable for significant agglomeration.
At Least One Detection
P(≥1)=1−exp(−cV): Calculate the detection rate of sampling at least once based on the input, and provide local sensitivity curves and data export.
ideal Poisson sampling and 100% detection efficiency; actual detection also depends on the method recovery rate.
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