Oxygen transport parameters

We would like to point out that an order parameter indicates the static property of the lipid bilayer, whereas the rotational motion, the oxygen transport parameter (Section 4.1), and the chain bending (Section 4.4) characterize membrane dynamics (membrane fluidity) that report on rotational diffusion of alkyl chains, translational diffusion of oxygen molecules, and frequency of alkyl chain bending, respectively. The EPR spin-labeling approach also makes it possible to monitor another bulk property of lipid bilayer membranes, namely local membrane hydrophobicity. 

Here x from Equation 10.4 is changed to the two-membrane domain FOT and SLOT with the depth fixed (the same spin label is distributed between the FOT and SLOT domains). W(FOT) and W(SLOT) are oxygen transport parameters in each domain and represent the collision rate in samples equilibrated with air. Figure 10.9 illustrates the basis of the discrimination by oxygen transport (DOT) method, showing saturation-recovery EPR signals for 5-SASL in membranes... 

Ashikawa, I., J.-J. Yin, W. K. Subczynski, T. Kouyama, J. S. Hyde, and A. Kusumi. 1994. Molecular organization and dynamics in bacteriorhodopsin-rich reconstituted membranes Discrimination of lipid environments by the oxygen transport parameter using a pulse ESR spin-labeling technique. Biochemistry 33 4947 1952. 

Kusumi, A., W. K. Subczynski, and J. S. Hyde. 1982b. Oxygen transport parameter in membranes as deduced by saturation recovery measurements of spin-lattice relaxation times of spin labels. Proc. Natl. Acad. Sci. USA 79 1854-1858. 

Solution to this equation with appropriate initial and boundary conditions leads to the determination of the oxygen transport parameters. 

Perovskite Materials and Related Compounds Oxygen Transport Parameters... 

Table 12. Parameters of reversible oxygen transport for haemoglobin and a microdisperse form of immobilized haemoglobin (pH 7.4, 37 °C, pC02 = 40 Torr, p02 = 0-150 Torr)...

Blood lactate concentrations may be used as another measure of tissue oxygenation and may show better correlation with outcome than 02 transport parameters in some patients. 

Transport properties of oxygen are better in the fluorinated polymer than in aqueous electrolytes. Although the diffusion coefficient is lower than in water, the oxygen solubility is largely enhanced so that the transport parameter D + c02 is higher than in water (160, 161). 

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