The phrase "a linear proportion between" is correct and usable in written English.
It can be used when discussing a relationship where one quantity is directly proportional to another in a linear manner.
Example: "The study found a linear proportion between the amount of sunlight and the growth rate of the plants."
Alternatives: "a direct relationship between" or "a linear relationship between".
In this paper, the coupling relationship between heating and electricity is simplified as a linear proportion based on an energy hub model [19, 20].
Using the chronoamperometry analysis, the redox current had a linear proportion with increasing DNA-t concentration.
Moreover, being in a linear proportion with blood pressure change, vessels movement is suitable for related blood pressure measurements, namely for pulse pressure measurements (the difference between the systolic and diastolic pressures) [ 26].
As a rule, brain size increases with body size, but not in a simple linear proportion.
It has been well established for the fish used in this experiment that there is a linear relationship between the proportion of domesticated alleles within the genotype and growth (Tymchuk and Devlin 2005) under conditions without competition or predation.
The most appropriate option for adjusting the observed growth curve through time was the log-transformation of time because there was a linear relationship between the proportion of second-eye surgery and the log-transformation of time.
This model included the natural logarithmic transformation of time in months (ranging from 1 to 26) as the independent variable because there was a linear relationship between the proportion of second-eye surgery and the log-transformation of time.
While there is a linear correlation between the proportion of Treg cells/total lymphocytes in BM samples by flow cytometry and CTLA4 expression by qPCR in 19 samples, it is also clear that for three of the 16 samples (one MM and 2 MGUS/PS) qPCR and flow cytometry data do not correlate.
In other words, individuals are strictly isometric for all linear measurements, including lengths and circumferences, and thus linear proportions are constant between individuals.
