Molecular motors are natures nanomachines, and are the essential agents of movement that are an integral part of many living organisms. The supramolecular machine, called the nuclear pore complex (NPC), controls the transport of all cellular material between the cytoplasm and the nucleus that occurs naturally in all biological cells. In the presence of appropriate chemical stimuli, the NPC opens or closes, like a gating mechanism, and permits the flow of material into and out of the nucleus. As a first step in understanding the design characteristics of the NPC, nanoscale studies were conducted to understand the transport characteristics of an idealized NPC model using CFD analysis, discrete element transport and coupled fluid-solid analysis. Results of pressure and velocity profiles obtained from the models indicate that the fluid density, flexibility of walls and the geometry of the flow passage are important in the design of NPC based nano- and micro-motors.
The knowledge whether and how chemical species react with tissues is important because of protection against harmful factors, diagnose of dermatological diseases, validation of dermatological procedures as well as effectiveness of topical therapies. In presented work the effects of chemical agents on plates of human fingernails were studied using Atomic Force Microscopy and Scanning Electron Microscopy. Apart from that, mapping of the elastic properties of the nails was also carried out. To obtain reliable measures of spatial evolution of the surface variations, recorded images were analyzed in terms of scaling invariance brought by fractal geometry, instead of common though not unique statistical measures.