Membrane transport organ models

The flux vector accounts for mass transport by both convection (i.e., blood flow, interstitial fluid flow) and conduction (i.e., molecular diffusion), whereas S describes membrane transport between adjacent compartments and irreversible elimination processes. For the three-subcompartment organ model presented in Figure 2, with concentration both space- and time-dependent, the conservation equations are... 

Other Cellular Self-Organization Mechanisms. Much emphasis has been placed in this section on the membrane based Ca2+ models involving charged membrane transport mediating species. However, a host of physically reasonable cellular self-organization phenomena present themselves. In this subsection we shall briefly discuss some of them. 

As well as being the causative organisms of a number of major human and animal diseases (e.g. cysticercosis, hydatidosis), cestodes serve as elegant experimental models for the study of fundamental biological phenomena. These include not only problems of specific parasitological interest, such as host-specificity, but also more basic problems such as enzyme dynamics, membrane transport and cell and tissue differentiation (especially asexual/sexual differentiation), common to many other biological fields. 

Surfactant aggregates (microemulsions, micelles, monolayers, vesicles, and liquid crystals) are recently the subject of extensive basic and applied research, because of their inherently interesting chemistry, as well as their diverse technical applications in such fields as petroleum, agriculture, pharmaceuticals, and detergents. Some of the important systems which these aggregates may model are enzyme catalysis, membrane transport, and drug delivery. More practical uses for them are enhanced tertiary oil recovery, emulsion polymerization, and solubilization and detoxification of pesticides and other toxic organic chemicals. 

Juang, R. S., Lee, S. H., Huang, R. H. (1998). Modeling of amine-facilitated hquid membrane transport ofbinary organic acids. Sep. Sci. Technol., 33, 2379-95. 

Organic chemists rely on amphiphilic lipids to build up membranes in water—the only organic reaction medium of nature. Biological molecular machinery is based on lipid membrane potentials. Artificial models so far do not work like cell membranes in vectorial transport and charge separation chains, but they look good under the electron microscope. 

Way ( ) applied the competitive transport model of Nllya and Noble ( ) to the prediction of facilitation factors for competitive transport of COj and HjS In Ion exchange membranes containing organic amine carriers. The results of the numerical simulations are shown in Table 2. The agreement Is very good for CO, and qualitative for H,S. 

Machado et al. [25] reported solvent fluxes for alcohols, paraffins, acetone, and water and presented a model describing solvent transport through solvent-resistant NF membranes (MPF-50, M.W.C.O. 700 Da, Koch, USA). They concluded that both viscosity and surface tension are major parameters that influence the solvent flux. Yang et al. (2001) showed that the transport mechanism by NF polymer membranes with organic solvents is not based solely on viscous flow through pores or simple molecular diffusion, and there must be some interaction between the solvent and the membrane (surface tension, sorption, and hydrophilicity or hydrophobicity of interfaces), dependent on the membrane material and properties of the solvent, which are important in determining the solvent flux. 

The above phenomena have a bearing on various physiological processes, e.g. membrane transport, oscillatory phenomena in cells and living organism, models for sense of taste and smell and flow system associated with cardiac rhythms. 

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