Occupancy Principle: Nonidentity with Mean Transit Time

Occupancy principle: identity with that of mean transit time of tracers in biological systems.

Mean transit time and mean residence time for linear diffusion–convection–reaction transport system

Characteristic times for transport processes in biological systems may be evaluated as mean transit times (MTTs) (for transit states) or mean residence times (MRT) (for steady states). It is shown in a general framework of a (linear) reaction–diffusion–convection equation that these two times are related. Analytical formulas are also derived to calculate moments of exit time distribution using ...

Mean Pulmonary Transit Time in First - Pass Studies

We studied the measurement reproducibility of mean pulmonary transit time in first-pass radionuclide angiography. Two bolus injections of mTc HDP were administered into each human subject approximately five minutes apart. Patients did not move between studies. The same regions of interest were used in both studies. Transit time measurement of the mTc from the right ventricle to the left ventric...

Parenchymal mean transit time analysis of 99mTc-DTPA captopril renography.

UNLABELLED Proposed renal hemodynamic mechanisms of captopril suggest that quantitation of renographic retention parameters should help identify patients suspected of having renovascular disease. The parenchymal mean transit time (MTT) is theoretically superior to other measures of retention, but data supporting its superiority are few. METHODS Two groups of subjects were studied with diethyl...

Large Deviations Principle for Occupancy Problems with Colored Balls

A large deviations principle (LDP), demonstrated for occupancy problems with indistinguishable balls, is generalized to the case in which balls are distinguished by a finite number of colors. The colors of the balls are chosen independently from the occupancy process itself. There are r balls thrown into n urns with the probability of a ball entering a given urn being 1/n (i.e. Maxwell–Boltzman...