Filament region surface

Studies have also been performed on surface filaments which form between more widely separated electrodes placed on the surface of the amorphous material. This permits easy access to the filament region for direct physical measurements. However, it is likely that entirely different phenomena dominate in such a scaled up model. For example, in the geometries used for the study of surface filaments, diffusion and thermal effects are enhanced by inefficient cooling and long thermal time constants. Nevertheless, these studies discussed below have contributed valuable insight into the dynamics of structure changes in these materials. 

Filaments associated with Parkinson s disease and dementia with Lewy bodies are unbranched, with a length of 200-600 nm and a width of 5-10 nm. Full-length a-synuclein is present, with its amino- and carboxy-termini being exposed on the filament surface. The core of the filament extends over a stretch of about 70 amino acids that overlaps almost entirely with the lipid-binding region of a-synuclein. Of the three human synucleins, only a-synuclein is associated with the filamentous inclusions of Lewy body diseases. 

If the cross-links or polymers are severed, then some elastic energy is released and the system will adopt a new (larger) equilibrium volume where greater distortion is conferred upon a meshwork that has fewer cross-links. Thus, upon increases in Ca2+, gelsolin activity leads to an increase in the volume of the actin-filament network. The additional influence of myosin on such a meshwork is similar to that proposed in the Stossel model. Thus, three-dimensional Ca2+ gradients (between a localised region of the cell surface and an external structure) can result in complex shape changes. 

It comprises an axially mounted W filament and three cylindrical collectors Ci,Ci, and Ci. All collectors are maintained at the same positive potential with respect to the W filament, but only the emission current collected from Ci is recorded. In the region of C2 the temperature and the surface concentration of adsorbate on the emitter are assumed to be uniform. 

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