Table 1.

Definition of symbols and abbreviations

Abbreviations/acronyms	Definition
MRS	Magnetic resonance spectroscopy.
MRR	Magnetic resonance relaxography.
T1	Longitudinal relaxation time constant.
R1 (≡ T1−1)	Longitudinal relaxation rate constant.
T2	Transverse relaxation time constant.
RRe	Extracellular relaxation reagent.
GdDTPA2−	Gadolinium diethylenetriamine penta-acetate.
IR	Inversion recovery experiment for T1 measurement.
tI	Delay time between 180° and 90° RF pulses in IR experiment.
R1L	Apparent R1 of component with larger T1 value.
R1S	Apparent R1 of component with smaller T1 value.
aL	Apparent population of component with larger T1 value.
aS	Apparent population of component with smaller T1 value.
2SX	Two-site exchange analysis model used to measure equilibrium transmembrane water exchange kinetics.
R10	Measured 1H2O R1 of a sample in absence of RRe.
R1i	R1 of intracellular water.
R1e0	R1 of extracellular water before RRe.
r1e	RRe relaxivity.
τi	Mean intracellular water molecule lifetime.
τe	Mean extracellular water molecule lifetime.
kie (≡ τi−1)	Pseudo-first-order rate constant for equilibrium water efflux.
kei	Pseudo-first-order rate constant for equilibrium water influx.
pi	Intracellular water mole fraction.
pe	Extracellular water mole fraction.
Pf	Osmotic or hydraulic water permeability coefficient.
Pd	Diffusional water permeability coefficient.
Pw	Steady-state water permeability coefficient with active and passive components: Pw = Pw(active) + Pw(passive).
V	Yeast cell volume.
A	Yeast cell surface area.
r	Yeast cell radius (modeled as a sphere).