Dispersal, of biological

Raicu, V. 1999. Dielectric dispersion of biological matter Model combining Debye-type and universal responses. Phys. Rev. E 60 4667-80. 

For a particle diameter of about 1 fim, x 2 x l(F cm-, and g a 0.2, a Asg of ca. 3SOOO is obtained at room temperature. The dispersion occurs in the low-frequency range of 1—10 kHz, in quantitative agreement with the relaxation time given by (46). There can be little doubt that the still more remarkable low-frequency dielectric dispersion of biological cells and tissue is also due to such counterion-polarization effects. 

An essential characteristic of the US transition westwards was the fact that settlers did not occupy all of the territory, as homogeneous models assume [137], but followed the course of the major rivers and lakes and settled near them to make use of their resources [113,133]. Therefore, landscape heterogeneities should have played an essential role in the process of migration. This situation is similar to the case of dispersion of biological species along the margins of rivers and streams [220,63]. 

When the problem is to disrupt Ughtly bonded clusters or agglomerates, a new aspect of fine grinding enters. This may be iUustrated by the breakdown of pigments to incorporate them in liquid vehicles in the making of paints, and the disruption of biological cells to release soluble produces. Purees, food pastes, pulps, and the like are processed by this type of mill. Dispersion is also associated with the formation of emulsions which are basically two-fluid systems. Syrups, sauces, milk, ointments, creams, lotions, and asphalt and water-paint emulsions are in this categoiy. 

Complete resolution was not achieved due to the carryover of interfering substances which frequently occurs when separating the components of biological samples. The column carried a reverse phase, but as the mobile phase contained low concentrations of lauryl sulfate, some would have adsorbed on the surface of the stationary phase and significantly modified its interacting properties. The retention mechanism is likely to have involved both ionic interactions with the adsorbed ion exchanger together with dispersive interactions with any exposed areas of the reverse phase. 

Take advantage of ongoing research aimed at the development of models of the airflow within aircraft, terminals, and so forth, based on empirical studies of specific facilities, and explore the dispersal of chemical/biological simulants under various release scenarios ... 

There has been considerable recent activity developing appropriate parameters to allow semi-empirical methods to describe a variety of biologically important systems, and their related properties, such as (i) enzyme reactivity, including both over- and through-barrier processes, (ii) conformations of flexible molecules such as carbohydrates, (iii) reactivity of metalloenzymes and (iv) the prediction of non-covalent interactions by addition of an empirical dispersive correction. In this review, we first outline our developing parameterisation strategy and then discuss progress that has been made in the areas outlined above. 

The poor dispersibility of CNTs in biological media can affect both the cytotoxicity [38] and the in vivo toxicity [39] of such nanomaterials. 

Wang, X. et al. (2010) Quantitative techniques for assessing and controlling the dispersion and biological effects of multiwalled carbon nanotubes in mammalian tissue culture cells. ACS Nano, 4 (12), 7241-7252. 

PEG is hydrophilic and is widely used in biological research because it protects surfaces from interacting with cells or proteins. Thus, coated particles may result in increased blood circulation time. For their preparation, 10-mg magnetite particles were dispersed in 1.0 mU of deoxygenated water by sonication for 30 min. The aqueous dispersion of MNPs was dissolved in the aqueous cores of reverse micelles... 

The majority of CYP enzymes are located in a hydrophobic environment in the endoplasmic reticulum of cells, although cytosolic enzymes also exist, such as CYP101. In order to mimic the physiological environment of CYP enzymes, a number of groups have used phospholipids to construct biosensors such as DDAB, dimeristoyl-L-a-phosphatidylcholine (DMPC), dilauroylphosphatidylethanolamine (DLPE) and distearoylphosphatidylethanolamine (DSPE). Phospholipid layers form stable vesicular dispersions that bear structural relationship with the phospholipid components of biologically important membranes. By this way a membranous environment is created that facilitates electron transfer between the enzyme s redox center and the electrode. 

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