Teorell studies

Teorell studied the system (6.1-1)—(6.1.5) graphically, by the isocline method, and also numerically. He recovered most of the features observed experimentally. This study was further elaborated by several investigators. Thus, Kobatake and Fujita [5], [6] criticized the original model for invoking the ad hoc equation (6.1.5). These authors assumed instead instantaneous relaxation of the resistance to its stationary value while preserving the overall order of the relevant ordinary differential equation (ODE) system by including consideration of the mechanical inertia of the liquid column in the manometer tube. 

Different versions of the above calculations, carried out for particular ionic contexts, form the basis of numerous studies of the ion-selective membrane transport, starting with classical papers by Teorell [7], and Meyer and Sievers [8]. Without attempting to give a full or merely fair account of all these studies, we shall mention here just a typical few Schlogl [5] (arbitrary number of ions in a monopolar membrane), Spiegler [9] (am-bipolar ionic transport in a unipolar membrane and solution layers adjacent to it — concentration polarization), Oren and Litan [10], Brady and Turner [11], Rubinstein [12] (multipolar transport in a unipolar membrane and the adjacent solution layers—effects of concentration polarization upon... 

Generalized local Darcy s model of Teorell s oscillations (PDEs) [12]. In this section we formulate and study a local analogue of Teorell s model discussed previously. The main difference between the model to be discussed and the original one is the replacement of the ad hoc resistance relaxation equation (6.1.5) or (6.2.5) by a set of one-dimensional Nernst-Planck equations for locally electro-neutral convective electro-diffusion of ions across the filter (membrane). This filter is viewed as a homogenized aqueous porous medium, lacking any fixed charge and characterized... 

This is the name given to the study of the kinetics of drug absorption, distribution, metabolism, and excretion, all of which are rate-controlled. The earliest studies, which were concerned with inhaled anaesthetics (Widmark, 1920 Dominguez, 1933), were not suited for general application. The fundamental equations were introduced by T. Teorell (1937) in his studies of insulin action. He provided simple kinetic formulae to monitor the concentration of... 

Teorell, T., 1946. Application of square wave analysis to bioelectric studies. Acta Physiol. Scand. 12,... 

Recent experimental studies are due to Rastogi and co-workers [13, 14]. A schematic diagram of their experimental setup is shown in Fig. 11.1, which is similar to that of Teorell with some modifications. 

Earlier studies on theoretical thin membranes were continued by Teorell [S] and Meyer and Sievers [6], who in their theory attempted to interpret the behavior of practical, thick membranes, in contact on both sides with solutions containing the sort of ion which can produce a membrane potential. This initiated further research and many workers studied the perm-selective properties of ion-selective electrode membranes. As a result, ion transport across thick ion-selective membranes was considered as the basic concept of the theory of ion-selective electrodes. This theory was further elaborated by Eisenmann, Simon, and Buck. 

Teorell, T., 1935. Studies on the diffusion effect upon ionic distribution. I. Some theoretical considerations. Proc. Natl. Acad. Sci. U. S. A. 21, 152-161. 

Teorell elaborated these experiments by studying the behavior of strong and weak acids in the cat s stomach. Perchloric acid gave results similar to those obtained with hydrochloric acid, but with sulfuric acid the concentration of hydrogen ions decreased more slowly. When he used formic, acetic, or lactic acids, Teorell found that titratable acidity decreased far more rapidly than when hydrochloric acid was used, and chloride increased faster. All these results were to be expected on the basis of Teorell s ideas, and he and his students believed that the role of his diffusion theory in what they called the regulation or control of gastric acidity had been firmly established. 

Although Kobatake and Fujita did not compare their predictions with experiments, their work showed that Teorell s assumption of a finite relaxation time for membrane resistance was unnecessary. Subsequent studies by Meares and Page [33, 39], using a very similar modeling perspective, confirmed that the flip-flop... 

Bala, K., Kumar, K., Saha, S.K., and Sristava, R.C. (2004) Single-capillary teorell oscillator-studies with nonelectrolytes. J. Colloid Interface Sci., 273,... 

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